common: compile libconfig as C++
authorSimon Marchi <simon.marchi@efficios.com>
Wed, 22 Sep 2021 01:00:28 +0000 (21:00 -0400)
committerJérémie Galarneau <jeremie.galarneau@efficios.com>
Wed, 17 Nov 2021 23:58:46 +0000 (18:58 -0500)
As seen previously, make some global variables that need to be exported
non-const.

config_element_tracker_pid_target_legacy seems unused and clang gives an
unused warning. It was not exposed publicly, so I think it's safe to
remove it.

Change-Id: I6f9e7d77a7a04b02ae6585383c11389869b4a79a
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
src/common/config/Makefile.am
src/common/config/ini.c [deleted file]
src/common/config/ini.cpp [new file with mode: 0644]
src/common/config/session-config.c [deleted file]
src/common/config/session-config.cpp [new file with mode: 0644]

index aaeeea72157bfdc2b72990c36a96a642afa4188c..faa4a38356d35dea93831449c588e3053734844c 100644 (file)
@@ -2,8 +2,13 @@
 
 noinst_LTLIBRARIES = libconfig.la
 
-libconfig_la_SOURCES = ini.c ini.h session-config.c session-config.h \
-               config-session-abi.h config-internal.h
+libconfig_la_SOURCES = \
+       config-internal.h \
+       config-session-abi.h \
+       ini.cpp \
+       ini.h \
+       session-config.cpp \
+       session-config.h
 libconfig_la_CPPFLAGS = $(libxml2_CFLAGS) $(AM_CPPFLAGS)
 libconfig_la_LIBADD = ${libxml2_LIBS}
 
diff --git a/src/common/config/ini.c b/src/common/config/ini.c
deleted file mode 100644 (file)
index 1d967a4..0000000
+++ /dev/null
@@ -1,218 +0,0 @@
-/*
- * inih -- simple .INI file parser
- *
- * The "inih" library is distributed under the New BSD license:
- *
- * Copyright (C) 2009 Brush Technology - All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *     * Redistributions of source code must retain the above copyright notice,
- *     this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *     notice, this list of conditions and the following disclaimer in the
- *     documentation and/or other materials provided with the distribution.
- *     * Neither the name of Brush Technology nor the names of its contributors
- *     may be used to endorse or promote products derived from this software
- *     without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY BRUSH TECHNOLOGY ''AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
- * EVENT SHALL BRUSH TECHNOLOGY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
- * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
- * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * http://code.google.com/p/inih/
- */
-
-#include <stdio.h>
-#include <ctype.h>
-#include <string.h>
-#include <common/common.h>
-
-#include "ini.h"
-
-#if !INI_USE_STACK
-#include <stdlib.h>
-#endif
-
-#define MAX_SECTION 50
-#define MAX_NAME 50
-
-/* Strip whitespace chars off end of given string, in place. Return s. */
-static char* rstrip(char* s)
-{
-       char* p = s + strlen(s);
-
-       while (p > s && isspace((unsigned char)(*--p)))
-               *p = '\0';
-       return s;
-}
-
-/* Return pointer to first non-whitespace char in given string. */
-static char* lskip(const char* s)
-{
-       while (*s && isspace((unsigned char)(*s)))
-               s++;
-       return (char*)s;
-}
-
-/*
- * Return pointer to first char c or ';' comment in given string, or pointer to
- * null at end of string if neither found. ';' must be prefixed by a whitespace
- * character to register as a comment.
- */
-static char* find_char_or_comment(const char* s, char c)
-{
-       int was_whitespace = 0;
-
-       while (*s && *s != c && !(was_whitespace && *s == ';')) {
-               was_whitespace = isspace((unsigned char)(*s));
-               s++;
-       }
-       return (char*)s;
-}
-
-/* Version of strncpy that ensures dest (size bytes) is null-terminated. */
-static char* strncpy0(char* dest, const char* src, size_t size)
-{
-       strncpy(dest, src, size - 1);
-       dest[size - 1] = '\0';
-       return dest;
-}
-
-/* See documentation in header file. */
-int ini_parse_file(FILE* file, ini_entry_handler handler, void* user)
-{
-       /* Uses a fair bit of stack (use heap instead if you need to) */
-#if INI_USE_STACK
-       char line[INI_MAX_LINE];
-#else
-       char* line;
-#endif
-       char section[MAX_SECTION] = "";
-       char prev_name[MAX_NAME] = "";
-
-       char* start;
-       char* end;
-       char* name;
-       char* value;
-       int lineno = 0;
-       int error = 0;
-
-#if !INI_USE_STACK
-       line = (char*)zmalloc(INI_MAX_LINE);
-       if (!line) {
-               return -2;
-       }
-#endif
-
-       /* Scan through file line by line */
-       while (fgets(line, INI_MAX_LINE, file) != NULL) {
-               lineno++;
-
-               start = line;
-#if INI_ALLOW_BOM
-               if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
-                       (unsigned char)start[1] == 0xBB &&
-                       (unsigned char)start[2] == 0xBF) {
-                       start += 3;
-               }
-#endif
-               start = lskip(rstrip(start));
-
-               if (*start == ';' || *start == '#') {
-                       /*
-                        * Per Python ConfigParser, allow '#' comments at
-                        * start of line.
-                        */
-               }
-#if INI_ALLOW_MULTILINE
-               else if (*prev_name && *start && start > line) {
-                       /* Non-black line with leading whitespace, treat as
-                        * continuation of previous name's value
-                        * (as per Python ConfigParser).
-                        */
-                       if (handler(user, section, prev_name, start) < 0 &&
-                               !error) {
-                               error = lineno;
-                       }
-               }
-#endif
-               else if (*start == '[') {
-                       /* A "[section]" line */
-                       end = find_char_or_comment(start + 1, ']');
-                       if (*end == ']') {
-                               *end = '\0';
-                               strncpy0(section, start + 1, sizeof(section));
-                               *prev_name = '\0';
-                       }
-                       else if (!error) {
-                               /* No ']' found on section line */
-                               error = lineno;
-                       }
-               }
-               else if (*start && *start != ';') {
-                       /* Not a comment, must be a name[=:]value pair */
-                       end = find_char_or_comment(start, '=');
-                       if (*end != '=') {
-                               end = find_char_or_comment(start, ':');
-                       }
-                       if (*end == '=' || *end == ':') {
-                               *end = '\0';
-                               name = rstrip(start);
-                               value = lskip(end + 1);
-                               end = find_char_or_comment(value, '\0');
-                               if (*end == ';') {
-                                       *end = '\0';
-                               }
-
-                               rstrip(value);
-
-                               /*
-                                * Valid name[=:]value pair found, call
-                                * handler
-                                */
-                               strncpy0(prev_name, name, sizeof(prev_name));
-                               if (handler(user, section, name, value) < 0 &&
-                                       !error) {
-                                       error = lineno;
-                               }
-                       }
-                       else if (!error) {
-                               /* No '=' or ':' found on name[=:]value line */
-                               error = lineno;
-                       }
-               }
-       }
-
-#if !INI_USE_STACK
-       free(line);
-#endif
-
-       return error;
-}
-
-/* See documentation in header file. */
-int ini_parse(const char* filename, ini_entry_handler handler, void* user)
-{
-       FILE* file;
-       int error;
-
-       file = fopen(filename, "r");
-       if (!file) {
-               return -1;
-       }
-
-       error = ini_parse_file(file, handler, user);
-       fclose(file);
-       return error;
-}
diff --git a/src/common/config/ini.cpp b/src/common/config/ini.cpp
new file mode 100644 (file)
index 0000000..1d967a4
--- /dev/null
@@ -0,0 +1,218 @@
+/*
+ * inih -- simple .INI file parser
+ *
+ * The "inih" library is distributed under the New BSD license:
+ *
+ * Copyright (C) 2009 Brush Technology - All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *     * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Brush Technology nor the names of its contributors
+ *     may be used to endorse or promote products derived from this software
+ *     without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY BRUSH TECHNOLOGY ''AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL BRUSH TECHNOLOGY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://code.google.com/p/inih/
+ */
+
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <common/common.h>
+
+#include "ini.h"
+
+#if !INI_USE_STACK
+#include <stdlib.h>
+#endif
+
+#define MAX_SECTION 50
+#define MAX_NAME 50
+
+/* Strip whitespace chars off end of given string, in place. Return s. */
+static char* rstrip(char* s)
+{
+       char* p = s + strlen(s);
+
+       while (p > s && isspace((unsigned char)(*--p)))
+               *p = '\0';
+       return s;
+}
+
+/* Return pointer to first non-whitespace char in given string. */
+static char* lskip(const char* s)
+{
+       while (*s && isspace((unsigned char)(*s)))
+               s++;
+       return (char*)s;
+}
+
+/*
+ * Return pointer to first char c or ';' comment in given string, or pointer to
+ * null at end of string if neither found. ';' must be prefixed by a whitespace
+ * character to register as a comment.
+ */
+static char* find_char_or_comment(const char* s, char c)
+{
+       int was_whitespace = 0;
+
+       while (*s && *s != c && !(was_whitespace && *s == ';')) {
+               was_whitespace = isspace((unsigned char)(*s));
+               s++;
+       }
+       return (char*)s;
+}
+
+/* Version of strncpy that ensures dest (size bytes) is null-terminated. */
+static char* strncpy0(char* dest, const char* src, size_t size)
+{
+       strncpy(dest, src, size - 1);
+       dest[size - 1] = '\0';
+       return dest;
+}
+
+/* See documentation in header file. */
+int ini_parse_file(FILE* file, ini_entry_handler handler, void* user)
+{
+       /* Uses a fair bit of stack (use heap instead if you need to) */
+#if INI_USE_STACK
+       char line[INI_MAX_LINE];
+#else
+       char* line;
+#endif
+       char section[MAX_SECTION] = "";
+       char prev_name[MAX_NAME] = "";
+
+       char* start;
+       char* end;
+       char* name;
+       char* value;
+       int lineno = 0;
+       int error = 0;
+
+#if !INI_USE_STACK
+       line = (char*)zmalloc(INI_MAX_LINE);
+       if (!line) {
+               return -2;
+       }
+#endif
+
+       /* Scan through file line by line */
+       while (fgets(line, INI_MAX_LINE, file) != NULL) {
+               lineno++;
+
+               start = line;
+#if INI_ALLOW_BOM
+               if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
+                       (unsigned char)start[1] == 0xBB &&
+                       (unsigned char)start[2] == 0xBF) {
+                       start += 3;
+               }
+#endif
+               start = lskip(rstrip(start));
+
+               if (*start == ';' || *start == '#') {
+                       /*
+                        * Per Python ConfigParser, allow '#' comments at
+                        * start of line.
+                        */
+               }
+#if INI_ALLOW_MULTILINE
+               else if (*prev_name && *start && start > line) {
+                       /* Non-black line with leading whitespace, treat as
+                        * continuation of previous name's value
+                        * (as per Python ConfigParser).
+                        */
+                       if (handler(user, section, prev_name, start) < 0 &&
+                               !error) {
+                               error = lineno;
+                       }
+               }
+#endif
+               else if (*start == '[') {
+                       /* A "[section]" line */
+                       end = find_char_or_comment(start + 1, ']');
+                       if (*end == ']') {
+                               *end = '\0';
+                               strncpy0(section, start + 1, sizeof(section));
+                               *prev_name = '\0';
+                       }
+                       else if (!error) {
+                               /* No ']' found on section line */
+                               error = lineno;
+                       }
+               }
+               else if (*start && *start != ';') {
+                       /* Not a comment, must be a name[=:]value pair */
+                       end = find_char_or_comment(start, '=');
+                       if (*end != '=') {
+                               end = find_char_or_comment(start, ':');
+                       }
+                       if (*end == '=' || *end == ':') {
+                               *end = '\0';
+                               name = rstrip(start);
+                               value = lskip(end + 1);
+                               end = find_char_or_comment(value, '\0');
+                               if (*end == ';') {
+                                       *end = '\0';
+                               }
+
+                               rstrip(value);
+
+                               /*
+                                * Valid name[=:]value pair found, call
+                                * handler
+                                */
+                               strncpy0(prev_name, name, sizeof(prev_name));
+                               if (handler(user, section, name, value) < 0 &&
+                                       !error) {
+                                       error = lineno;
+                               }
+                       }
+                       else if (!error) {
+                               /* No '=' or ':' found on name[=:]value line */
+                               error = lineno;
+                       }
+               }
+       }
+
+#if !INI_USE_STACK
+       free(line);
+#endif
+
+       return error;
+}
+
+/* See documentation in header file. */
+int ini_parse(const char* filename, ini_entry_handler handler, void* user)
+{
+       FILE* file;
+       int error;
+
+       file = fopen(filename, "r");
+       if (!file) {
+               return -1;
+       }
+
+       error = ini_parse_file(file, handler, user);
+       fclose(file);
+       return error;
+}
diff --git a/src/common/config/session-config.c b/src/common/config/session-config.c
deleted file mode 100644 (file)
index 08d6685..0000000
+++ /dev/null
@@ -1,4153 +0,0 @@
-/*
- * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#include "lttng/tracker.h"
-#define _LGPL_SOURCE
-#include <ctype.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <inttypes.h>
-#include <dirent.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <stdbool.h>
-
-#include <common/defaults.h>
-#include <common/error.h>
-#include <common/macros.h>
-#include <common/utils.h>
-#include <common/dynamic-buffer.h>
-#include <common/compat/getenv.h>
-#include <lttng/lttng-error.h>
-#include <libxml/parser.h>
-#include <libxml/valid.h>
-#include <libxml/xmlschemas.h>
-#include <libxml/tree.h>
-#include <lttng/lttng.h>
-#include <lttng/snapshot.h>
-#include <lttng/rotation.h>
-#include <lttng/userspace-probe.h>
-
-#include "session-config.h"
-#include "config-internal.h"
-
-#define CONFIG_USERSPACE_PROBE_LOOKUP_METHOD_NAME_MAX_LEN 7
-
-struct handler_filter_args {
-       const char* section;
-       config_entry_handler_cb handler;
-       void *user_data;
-};
-
-struct session_config_validation_ctx {
-       xmlSchemaParserCtxtPtr parser_ctx;
-       xmlSchemaPtr schema;
-       xmlSchemaValidCtxtPtr schema_validation_ctx;
-};
-
-const char * const config_element_all = "all";
-LTTNG_EXPORT const char * const config_str_yes = "yes";
-LTTNG_EXPORT const char * const config_str_true = "true";
-LTTNG_EXPORT const char * const config_str_on = "on";
-LTTNG_EXPORT const char * const config_str_no = "no";
-LTTNG_EXPORT const char * const config_str_false = "false";
-LTTNG_EXPORT const char * const config_str_off = "off";
-LTTNG_EXPORT const char * const config_xml_encoding = "UTF-8";
-LTTNG_EXPORT const size_t config_xml_encoding_bytes_per_char = 2;      /* Size of the encoding's largest character */
-LTTNG_EXPORT const char * const config_xml_indent_string = "\t";
-LTTNG_EXPORT const char * const config_xml_true = "true";
-LTTNG_EXPORT const char * const config_xml_false = "false";
-
-const char * const config_element_channel = "channel";
-const char * const config_element_channels = "channels";
-const char * const config_element_domain = "domain";
-const char * const config_element_domains = "domains";
-const char * const config_element_event = "event";
-const char * const config_element_events = "events";
-const char * const config_element_context = "context";
-const char * const config_element_contexts = "contexts";
-const char * const config_element_attributes = "attributes";
-const char * const config_element_exclusion = "exclusion";
-const char * const config_element_exclusions = "exclusions";
-const char * const config_element_function_attributes = "function_attributes";
-const char * const config_element_probe_attributes = "probe_attributes";
-const char * const config_element_symbol_name = "symbol_name";
-const char * const config_element_address = "address";
-const char * const config_element_offset = "offset";
-
-const char * const config_element_userspace_probe_lookup = "lookup_method";
-const char * const config_element_userspace_probe_lookup_function_default = "DEFAULT";
-const char * const config_element_userspace_probe_lookup_function_elf = "ELF";
-const char * const config_element_userspace_probe_lookup_tracepoint_sdt = "SDT";
-const char * const config_element_userspace_probe_location_binary_path = "binary_path";
-const char * const config_element_userspace_probe_function_attributes = "userspace_probe_function_attributes";
-const char * const config_element_userspace_probe_function_location_function_name = "function_name";
-const char * const config_element_userspace_probe_tracepoint_attributes = "userspace_probe_tracepoint_attributes";
-const char * const config_element_userspace_probe_tracepoint_location_provider_name = "provider_name";
-const char * const config_element_userspace_probe_tracepoint_location_probe_name = "probe_name";
-
-const char * const config_element_name = "name";
-const char * const config_element_enabled = "enabled";
-const char * const config_element_overwrite_mode = "overwrite_mode";
-const char * const config_element_subbuf_size = "subbuffer_size";
-const char * const config_element_num_subbuf = "subbuffer_count";
-const char * const config_element_switch_timer_interval = "switch_timer_interval";
-const char * const config_element_read_timer_interval = "read_timer_interval";
-const char * const config_element_monitor_timer_interval = "monitor_timer_interval";
-const char * const config_element_blocking_timeout = "blocking_timeout";
-const char * const config_element_output = "output";
-const char * const config_element_output_type = "output_type";
-const char * const config_element_tracefile_size = "tracefile_size";
-const char * const config_element_tracefile_count = "tracefile_count";
-const char * const config_element_live_timer_interval = "live_timer_interval";
-const char * const config_element_discarded_events = "discarded_events";
-const char * const config_element_lost_packets = "lost_packets";
-const char * const config_element_type = "type";
-const char * const config_element_buffer_type = "buffer_type";
-const char * const config_element_session = "session";
-const char * const config_element_sessions = "sessions";
-const char * const config_element_context_perf = "perf";
-const char * const config_element_context_app = "app";
-const char * const config_element_context_app_provider_name = "provider_name";
-const char * const config_element_context_app_ctx_name = "ctx_name";
-const char * const config_element_config = "config";
-const char * const config_element_started = "started";
-const char * const config_element_snapshot_mode = "snapshot_mode";
-const char * const config_element_loglevel = "loglevel";
-const char * const config_element_loglevel_type = "loglevel_type";
-const char * const config_element_filter = "filter";
-const char * const config_element_filter_expression = "filter_expression";
-const char * const config_element_snapshot_outputs = "snapshot_outputs";
-const char * const config_element_consumer_output = "consumer_output";
-const char * const config_element_destination = "destination";
-const char * const config_element_path = "path";
-const char * const config_element_net_output = "net_output";
-const char * const config_element_control_uri = "control_uri";
-const char * const config_element_data_uri = "data_uri";
-const char * const config_element_max_size = "max_size";
-const char * const config_element_pid = "pid";
-const char * const config_element_pids = "pids";
-const char * const config_element_shared_memory_path = "shared_memory_path";
-
-const char * const config_element_process_attr_id = "id";
-const char * const config_element_process_attr_tracker_pid = "pid_process_attr_tracker";
-const char * const config_element_process_attr_tracker_vpid = "vpid_process_attr_tracker";
-const char * const config_element_process_attr_tracker_uid = "uid_process_attr_tracker";
-const char * const config_element_process_attr_tracker_vuid = "vuid_process_attr_tracker";
-const char * const config_element_process_attr_tracker_gid = "gid_process_attr_tracker";
-const char * const config_element_process_attr_tracker_vgid = "vgid_process_attr_tracker";
-const char * const config_element_process_attr_trackers = "process_attr_trackers";
-const char * const config_element_process_attr_values = "process_attr_values";
-const char * const config_element_process_attr_value_type = "process_attr_value_type";
-const char * const config_element_process_attr_pid_value = "pid";
-const char * const config_element_process_attr_vpid_value = "vpid";
-const char * const config_element_process_attr_uid_value = "uid";
-const char * const config_element_process_attr_vuid_value = "vuid";
-const char * const config_element_process_attr_gid_value = "gid";
-const char * const config_element_process_attr_vgid_value = "vgid";
-const char * const config_element_process_attr_tracker_type = "process_attr_tracker_type";
-
-/* Used for support of legacy tracker serialization (< 2.12). */
-const char * const config_element_trackers_legacy = "trackers";
-const char * const config_element_pid_tracker_legacy = "pid_tracker";
-const char * const config_element_tracker_targets_legacy = "targets";
-const char * const config_element_tracker_pid_target_legacy = "pid_target";
-const char * const config_element_tracker_pid_legacy = "pid";
-
-const char * const config_element_rotation_schedules = "rotation_schedules";
-const char * const config_element_rotation_schedule_periodic = "periodic";
-const char * const config_element_rotation_schedule_periodic_time_us = "time_us";
-const char * const config_element_rotation_schedule_size_threshold = "size_threshold";
-const char * const config_element_rotation_schedule_size_threshold_bytes = "bytes";
-
-const char * const config_domain_type_kernel = "KERNEL";
-const char * const config_domain_type_ust = "UST";
-const char * const config_domain_type_jul = "JUL";
-const char * const config_domain_type_log4j = "LOG4J";
-const char * const config_domain_type_python = "PYTHON";
-
-const char * const config_buffer_type_per_pid = "PER_PID";
-const char * const config_buffer_type_per_uid = "PER_UID";
-const char * const config_buffer_type_global = "GLOBAL";
-
-const char * const config_overwrite_mode_discard = "DISCARD";
-const char * const config_overwrite_mode_overwrite = "OVERWRITE";
-
-const char * const config_output_type_splice = "SPLICE";
-const char * const config_output_type_mmap = "MMAP";
-
-const char * const config_loglevel_type_all = "ALL";
-const char * const config_loglevel_type_range = "RANGE";
-const char * const config_loglevel_type_single = "SINGLE";
-
-const char * const config_event_type_all = "ALL";
-const char * const config_event_type_tracepoint = "TRACEPOINT";
-const char * const config_event_type_probe = "PROBE";
-const char * const config_event_type_userspace_probe = "USERSPACE_PROBE";
-const char * const config_event_type_function = "FUNCTION";
-const char * const config_event_type_function_entry = "FUNCTION_ENTRY";
-const char * const config_event_type_noop = "NOOP";
-const char * const config_event_type_syscall = "SYSCALL";
-const char * const config_event_type_kprobe = "KPROBE";
-const char * const config_event_type_kretprobe = "KRETPROBE";
-
-const char * const config_event_context_pid = "PID";
-const char * const config_event_context_procname = "PROCNAME";
-const char * const config_event_context_prio = "PRIO";
-const char * const config_event_context_nice = "NICE";
-const char * const config_event_context_vpid = "VPID";
-const char * const config_event_context_tid = "TID";
-const char * const config_event_context_vtid = "VTID";
-const char * const config_event_context_ppid = "PPID";
-const char * const config_event_context_vppid = "VPPID";
-const char * const config_event_context_pthread_id = "PTHREAD_ID";
-const char * const config_event_context_hostname = "HOSTNAME";
-const char * const config_event_context_ip = "IP";
-const char * const config_event_context_perf_thread_counter = "PERF_THREAD_COUNTER";
-const char * const config_event_context_app = "APP";
-const char * const config_event_context_interruptible = "INTERRUPTIBLE";
-const char * const config_event_context_preemptible = "PREEMPTIBLE";
-const char * const config_event_context_need_reschedule = "NEED_RESCHEDULE";
-const char * const config_event_context_migratable = "MIGRATABLE";
-const char * const config_event_context_callstack_user= "CALLSTACK_USER";
-const char * const config_event_context_callstack_kernel = "CALLSTACK_KERNEL";
-const char * const config_event_context_cgroup_ns = "CGROUP_NS";
-const char * const config_event_context_ipc_ns = "IPC_NS";
-const char * const config_event_context_mnt_ns = "MNT_NS";
-const char * const config_event_context_net_ns = "NET_NS";
-const char * const config_event_context_pid_ns = "PID_NS";
-const char * const config_event_context_time_ns = "TIME_NS";
-const char * const config_event_context_user_ns = "USER_NS";
-const char * const config_event_context_uts_ns = "UTS_NS";
-const char * const config_event_context_uid = "UID";
-const char * const config_event_context_euid = "EUID";
-const char * const config_event_context_suid = "SUID";
-const char * const config_event_context_gid = "GID";
-const char * const config_event_context_egid = "EGID";
-const char * const config_event_context_sgid = "SGID";
-const char * const config_event_context_vuid = "VUID";
-const char * const config_event_context_veuid = "VEUID";
-const char * const config_event_context_vsuid = "VSUID";
-const char * const config_event_context_vgid = "VGID";
-const char * const config_event_context_vegid = "VEGID";
-const char * const config_event_context_vsgid = "VSGID";
-
-/* Deprecated symbols */
-LTTNG_EXPORT const char * const config_element_perf;
-
-enum process_event_node_phase {
-       CREATION = 0,
-       ENABLE = 1,
-};
-
-struct consumer_output {
-       int enabled;
-       char *path;
-       char *control_uri;
-       char *data_uri;
-};
-
-static int config_entry_handler_filter(struct handler_filter_args *args,
-               const char *section, const char *name, const char *value)
-{
-       int ret = 0;
-       struct config_entry entry = { section, name, value };
-
-       LTTNG_ASSERT(args);
-
-       if (!section || !name || !value) {
-               ret = -EIO;
-               goto end;
-       }
-
-       if (args->section) {
-               if (strcmp(args->section, section)) {
-                       goto end;
-               }
-       }
-
-       ret = args->handler(&entry, args->user_data);
-end:
-       return ret;
-}
-
-int config_get_section_entries(const char *override_path, const char *section,
-               config_entry_handler_cb handler, void *user_data)
-{
-       int ret = 0;
-       const char *path;
-       FILE *config_file = NULL;
-       struct handler_filter_args filter = { section, handler, user_data };
-
-       /* First, try system-wide conf. file. */
-       path = DEFAULT_DAEMON_SYSTEM_CONFIGPATH;
-
-       config_file = fopen(path, "r");
-       if (config_file) {
-               DBG("Loading daemon conf file at %s", path);
-               /*
-                * Return value is not very important here since error or not, we
-                * continue and try the next possible conf. file.
-                */
-               (void) ini_parse_file(config_file,
-                               (ini_entry_handler) config_entry_handler_filter,
-                               (void *) &filter);
-               fclose(config_file);
-       }
-
-       /* Second is the user local configuration. */
-       path = utils_get_home_dir();
-       if (path) {
-               char fullpath[PATH_MAX];
-
-               ret = snprintf(fullpath, sizeof(fullpath),
-                               DEFAULT_DAEMON_HOME_CONFIGPATH, path);
-               if (ret < 0) {
-                       PERROR("snprintf user conf. path");
-                       goto error;
-               }
-
-               config_file = fopen(fullpath, "r");
-               if (config_file) {
-                       DBG("Loading daemon user conf file at %s", path);
-                       /*
-                        * Return value is not very important here since error or not, we
-                        * continue and try the next possible conf. file.
-                        */
-                       (void) ini_parse_file(config_file,
-                                       (ini_entry_handler) config_entry_handler_filter,
-                                       (void *) &filter);
-                       fclose(config_file);
-               }
-       }
-
-       /* Final path is the one that the user might have provided. */
-       if (override_path) {
-               config_file = fopen(override_path, "r");
-               if (config_file) {
-                       DBG("Loading daemon command line conf file at %s", override_path);
-                       (void) ini_parse_file(config_file,
-                                       (ini_entry_handler) config_entry_handler_filter,
-                                       (void *) &filter);
-                       fclose(config_file);
-               } else {
-                       ERR("Failed to open daemon configuration file at %s",
-                               override_path);
-                       ret = -ENOENT;
-                       goto error;
-               }
-       }
-
-       /* Everything went well. */
-       ret = 0;
-
-error:
-       return ret;
-}
-
-int config_parse_value(const char *value)
-{
-       int i, ret = 0;
-       char *endptr, *lower_str;
-       size_t len;
-       unsigned long v;
-
-       len = strlen(value);
-       if (!len) {
-               ret = -1;
-               goto end;
-       }
-
-       v = strtoul(value, &endptr, 10);
-       if (endptr != value) {
-               ret = v;
-               goto end;
-       }
-
-       lower_str = zmalloc(len + 1);
-       if (!lower_str) {
-               PERROR("zmalloc");
-               ret = -errno;
-               goto end;
-       }
-
-       for (i = 0; i < len; i++) {
-               lower_str[i] = tolower(value[i]);
-       }
-
-       if (!strcmp(lower_str, config_str_yes) ||
-               !strcmp(lower_str, config_str_true) ||
-               !strcmp(lower_str, config_str_on)) {
-               ret = 1;
-       } else if (!strcmp(lower_str, config_str_no) ||
-               !strcmp(lower_str, config_str_false) ||
-               !strcmp(lower_str, config_str_off)) {
-               ret = 0;
-       } else {
-               ret = -1;
-       }
-
-       free(lower_str);
-end:
-       return ret;
-}
-
-/*
- * Returns a xmlChar string which must be released using xmlFree().
- */
-static xmlChar *encode_string(const char *in_str)
-{
-       xmlChar *out_str = NULL;
-       xmlCharEncodingHandlerPtr handler;
-       int out_len, ret, in_len;
-
-       LTTNG_ASSERT(in_str);
-
-       handler = xmlFindCharEncodingHandler(config_xml_encoding);
-       if (!handler) {
-               ERR("xmlFindCharEncodingHandler return NULL!. Configure issue!");
-               goto end;
-       }
-
-       in_len = strlen(in_str);
-       /*
-        * Add 1 byte for the NULL terminted character. The factor 4 here is
-        * used because UTF-8 characters can take up to 4 bytes.
-        */
-       out_len = (in_len * 4) + 1;
-       out_str = xmlMalloc(out_len);
-       if (!out_str) {
-               goto end;
-       }
-
-       ret = handler->input(out_str, &out_len, (const xmlChar *) in_str, &in_len);
-       if (ret < 0) {
-               xmlFree(out_str);
-               out_str = NULL;
-               goto end;
-       }
-
-       /* out_len is now the size of out_str */
-       out_str[out_len] = '\0';
-end:
-       return out_str;
-}
-
-struct config_writer *config_writer_create(int fd_output, int indent)
-{
-       int ret;
-       struct config_writer *writer;
-       xmlOutputBufferPtr buffer;
-
-       writer = zmalloc(sizeof(struct config_writer));
-       if (!writer) {
-               PERROR("zmalloc config_writer_create");
-               goto end;
-       }
-
-       buffer = xmlOutputBufferCreateFd(fd_output, NULL);
-       if (!buffer) {
-               goto error_destroy;
-       }
-
-       writer->writer = xmlNewTextWriter(buffer);
-       ret = xmlTextWriterStartDocument(writer->writer, NULL,
-               config_xml_encoding, NULL);
-       if (ret < 0) {
-               goto error_destroy;
-       }
-
-       ret = xmlTextWriterSetIndentString(writer->writer,
-               BAD_CAST config_xml_indent_string);
-       if (ret) {
-               goto error_destroy;
-       }
-
-       ret = xmlTextWriterSetIndent(writer->writer, indent);
-       if (ret) {
-               goto error_destroy;
-       }
-
-end:
-       return writer;
-error_destroy:
-       config_writer_destroy(writer);
-       return NULL;
-}
-
-int config_writer_destroy(struct config_writer *writer)
-{
-       int ret = 0;
-
-       if (!writer) {
-               ret = -EINVAL;
-               goto end;
-       }
-
-       if (xmlTextWriterEndDocument(writer->writer) < 0) {
-               WARN("Could not close XML document");
-               ret = -EIO;
-       }
-
-       if (writer->writer) {
-               xmlFreeTextWriter(writer->writer);
-       }
-
-       free(writer);
-end:
-       return ret;
-}
-
-int config_writer_open_element(struct config_writer *writer,
-       const char *element_name)
-{
-       int ret;
-       xmlChar *encoded_element_name;
-
-       if (!writer || !writer->writer || !element_name || !element_name[0]) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_element_name = encode_string(element_name);
-       if (!encoded_element_name) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterStartElement(writer->writer, encoded_element_name);
-       xmlFree(encoded_element_name);
-end:
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_write_attribute(struct config_writer *writer,
-               const char *name, const char *value)
-{
-       int ret;
-       xmlChar *encoded_name = NULL;
-       xmlChar *encoded_value = NULL;
-
-       if (!writer || !writer->writer || !name || !name[0]) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_name = encode_string(name);
-       if (!encoded_name) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_value = encode_string(value);
-       if (!encoded_value) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterWriteAttribute(writer->writer, encoded_name,
-                       encoded_value);
-end:
-       xmlFree(encoded_name);
-       xmlFree(encoded_value);
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_close_element(struct config_writer *writer)
-{
-       int ret;
-
-       if (!writer || !writer->writer) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterEndElement(writer->writer);
-end:
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_write_element_unsigned_int(struct config_writer *writer,
-               const char *element_name, uint64_t value)
-{
-       int ret;
-       xmlChar *encoded_element_name;
-
-       if (!writer || !writer->writer || !element_name || !element_name[0]) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_element_name = encode_string(element_name);
-       if (!encoded_element_name) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterWriteFormatElement(writer->writer,
-               encoded_element_name, "%" PRIu64, value);
-       xmlFree(encoded_element_name);
-end:
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_write_element_signed_int(struct config_writer *writer,
-               const char *element_name, int64_t value)
-{
-       int ret;
-       xmlChar *encoded_element_name;
-
-       if (!writer || !writer->writer || !element_name || !element_name[0]) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_element_name = encode_string(element_name);
-       if (!encoded_element_name) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterWriteFormatElement(writer->writer,
-               encoded_element_name, "%" PRIi64, value);
-       xmlFree(encoded_element_name);
-end:
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_write_element_bool(struct config_writer *writer,
-               const char *element_name, int value)
-{
-       return config_writer_write_element_string(writer, element_name,
-               value ? config_xml_true : config_xml_false);
-}
-
-int config_writer_write_element_double(struct config_writer *writer,
-               const char *element_name,
-               double value)
-{
-       int ret;
-       xmlChar *encoded_element_name;
-
-       if (!writer || !writer->writer || !element_name || !element_name[0]) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_element_name = encode_string(element_name);
-       if (!encoded_element_name) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterWriteFormatElement(
-                       writer->writer, encoded_element_name, "%f", value);
-       xmlFree(encoded_element_name);
-end:
-       return ret >= 0 ? 0 : ret;
-}
-
-int config_writer_write_element_string(struct config_writer *writer,
-               const char *element_name, const char *value)
-{
-       int ret;
-       xmlChar *encoded_element_name = NULL;
-       xmlChar *encoded_value = NULL;
-
-       if (!writer || !writer->writer || !element_name || !element_name[0] ||
-               !value) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_element_name = encode_string(element_name);
-       if (!encoded_element_name) {
-               ret = -1;
-               goto end;
-       }
-
-       encoded_value = encode_string(value);
-       if (!encoded_value) {
-               ret = -1;
-               goto end;
-       }
-
-       ret = xmlTextWriterWriteElement(writer->writer, encoded_element_name,
-                       encoded_value);
-end:
-       xmlFree(encoded_element_name);
-       xmlFree(encoded_value);
-       return ret >= 0 ? 0 : ret;
-}
-
-static
-void xml_error_handler(void *ctx, const char *format, ...)
-{
-       char *errMsg;
-       va_list args;
-       int ret;
-
-       va_start(args, format);
-       ret = vasprintf(&errMsg, format, args);
-       va_end(args);
-       if (ret == -1) {
-               ERR("String allocation failed in xml error handler");
-               return;
-       }
-
-       fprintf(stderr, "XML Error: %s", errMsg);
-       free(errMsg);
-}
-
-static
-void fini_session_config_validation_ctx(
-       struct session_config_validation_ctx *ctx)
-{
-       if (ctx->parser_ctx) {
-               xmlSchemaFreeParserCtxt(ctx->parser_ctx);
-       }
-
-       if (ctx->schema) {
-               xmlSchemaFree(ctx->schema);
-       }
-
-       if (ctx->schema_validation_ctx) {
-               xmlSchemaFreeValidCtxt(ctx->schema_validation_ctx);
-       }
-
-       memset(ctx, 0, sizeof(struct session_config_validation_ctx));
-}
-
-static
-char *get_session_config_xsd_path(void)
-{
-       char *xsd_path;
-       const char *base_path = lttng_secure_getenv(DEFAULT_SESSION_CONFIG_XSD_PATH_ENV);
-       size_t base_path_len;
-       size_t max_path_len;
-
-       if (!base_path) {
-               base_path = DEFAULT_SESSION_CONFIG_XSD_PATH;
-       }
-
-       base_path_len = strlen(base_path);
-       max_path_len = base_path_len +
-               sizeof(DEFAULT_SESSION_CONFIG_XSD_FILENAME) + 1;
-       xsd_path = zmalloc(max_path_len);
-       if (!xsd_path) {
-               goto end;
-       }
-
-       strcpy(xsd_path, base_path);
-       if (xsd_path[base_path_len - 1] != '/') {
-               xsd_path[base_path_len++] = '/';
-       }
-
-       strcpy(xsd_path + base_path_len, DEFAULT_SESSION_CONFIG_XSD_FILENAME);
-end:
-       return xsd_path;
-}
-
-static
-int init_session_config_validation_ctx(
-       struct session_config_validation_ctx *ctx)
-{
-       int ret;
-       char *xsd_path = get_session_config_xsd_path();
-
-       if (!xsd_path) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto end;
-       }
-
-       ctx->parser_ctx = xmlSchemaNewParserCtxt(xsd_path);
-       if (!ctx->parser_ctx) {
-               ERR("XSD parser context creation failed");
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-       xmlSchemaSetParserErrors(ctx->parser_ctx, xml_error_handler,
-               xml_error_handler, NULL);
-
-       ctx->schema = xmlSchemaParse(ctx->parser_ctx);
-       if (!ctx->schema) {
-               ERR("XSD parsing failed");
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       ctx->schema_validation_ctx = xmlSchemaNewValidCtxt(ctx->schema);
-       if (!ctx->schema_validation_ctx) {
-               ERR("XSD validation context creation failed");
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       xmlSchemaSetValidErrors(ctx->schema_validation_ctx, xml_error_handler,
-                       xml_error_handler, NULL);
-       ret = 0;
-
-end:
-       if (ret) {
-               fini_session_config_validation_ctx(ctx);
-       }
-
-       free(xsd_path);
-       return ret;
-}
-
-static
-int parse_uint(xmlChar *str, uint64_t *val)
-{
-       int ret;
-       char *endptr;
-
-       if (!str || !val) {
-               ret = -1;
-               goto end;
-       }
-
-       *val = strtoull((const char *) str, &endptr, 10);
-       if (!endptr || *endptr) {
-               ret = -1;
-       } else {
-               ret = 0;
-       }
-
-end:
-       return ret;
-}
-
-static
-int parse_int(xmlChar *str, int64_t *val)
-{
-       int ret;
-       char *endptr;
-
-       if (!str || !val) {
-               ret = -1;
-               goto end;
-       }
-
-       *val = strtoll((const char *) str, &endptr, 10);
-       if (!endptr || *endptr) {
-               ret = -1;
-       } else {
-               ret = 0;
-       }
-
-end:
-       return ret;
-}
-
-static
-int parse_bool(xmlChar *str, int *val)
-{
-       int ret = 0;
-
-       if (!str || !val) {
-               ret = -1;
-               goto end;
-       }
-
-       if (!strcmp((const char *) str, config_xml_true) ||
-                       !strcmp((const char *) str, "1")) {
-               *val = 1;
-       } else if (!strcmp((const char *) str, config_xml_false) ||
-                       !strcmp((const char *) str, "0")) {
-               *val = 0;
-       } else {
-               WARN("Invalid boolean value encountered (%s).",
-                       (const char *) str);
-               ret = -1;
-       }
-end:
-       return ret;
-}
-
-static
-int get_domain_type(xmlChar *domain)
-{
-       int ret;
-
-       if (!domain) {
-               goto error;
-       }
-
-       if (!strcmp((char *) domain, config_domain_type_kernel)) {
-               ret = LTTNG_DOMAIN_KERNEL;
-       } else if (!strcmp((char *) domain, config_domain_type_ust)) {
-               ret = LTTNG_DOMAIN_UST;
-       } else if (!strcmp((char *) domain, config_domain_type_jul)) {
-               ret = LTTNG_DOMAIN_JUL;
-       } else if (!strcmp((char *) domain, config_domain_type_log4j)) {
-               ret = LTTNG_DOMAIN_LOG4J;
-       } else if (!strcmp((char *) domain, config_domain_type_python)) {
-               ret = LTTNG_DOMAIN_PYTHON;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int get_buffer_type(xmlChar *buffer_type)
-{
-       int ret;
-
-       if (!buffer_type) {
-               goto error;
-       }
-
-       if (!strcmp((char *) buffer_type, config_buffer_type_global)) {
-               ret = LTTNG_BUFFER_GLOBAL;
-       } else if (!strcmp((char *) buffer_type, config_buffer_type_per_uid)) {
-               ret = LTTNG_BUFFER_PER_UID;
-       } else if (!strcmp((char *) buffer_type, config_buffer_type_per_pid)) {
-               ret = LTTNG_BUFFER_PER_PID;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int get_overwrite_mode(xmlChar *overwrite_mode)
-{
-       int ret;
-
-       if (!overwrite_mode) {
-               goto error;
-       }
-
-       if (!strcmp((char *) overwrite_mode, config_overwrite_mode_overwrite)) {
-               ret = 1;
-       } else if (!strcmp((char *) overwrite_mode,
-               config_overwrite_mode_discard)) {
-               ret = 0;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int get_output_type(xmlChar *output_type)
-{
-       int ret;
-
-       if (!output_type) {
-               goto error;
-       }
-
-       if (!strcmp((char *) output_type, config_output_type_mmap)) {
-               ret = LTTNG_EVENT_MMAP;
-       } else if (!strcmp((char *) output_type, config_output_type_splice)) {
-               ret = LTTNG_EVENT_SPLICE;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int get_event_type(xmlChar *event_type)
-{
-       int ret;
-
-       if (!event_type) {
-               goto error;
-       }
-
-       if (!strcmp((char *) event_type, config_event_type_all)) {
-               ret = LTTNG_EVENT_ALL;
-       } else if (!strcmp((char *) event_type, config_event_type_tracepoint)) {
-               ret = LTTNG_EVENT_TRACEPOINT;
-       } else if (!strcmp((char *) event_type, config_event_type_probe)) {
-               ret = LTTNG_EVENT_PROBE;
-       } else if (!strcmp((char *) event_type,
-                               config_event_type_userspace_probe)) {
-               ret = LTTNG_EVENT_USERSPACE_PROBE;
-       } else if (!strcmp((char *) event_type, config_event_type_function)) {
-               ret = LTTNG_EVENT_FUNCTION;
-       } else if (!strcmp((char *) event_type,
-                               config_event_type_function_entry)) {
-               ret = LTTNG_EVENT_FUNCTION_ENTRY;
-       } else if (!strcmp((char *) event_type, config_event_type_noop)) {
-               ret = LTTNG_EVENT_NOOP;
-       } else if (!strcmp((char *) event_type, config_event_type_syscall)) {
-               ret = LTTNG_EVENT_SYSCALL;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int get_loglevel_type(xmlChar *loglevel_type)
-{
-       int ret;
-
-       if (!loglevel_type) {
-               goto error;
-       }
-
-       if (!strcmp((char *) loglevel_type, config_loglevel_type_all)) {
-               ret = LTTNG_EVENT_LOGLEVEL_ALL;
-       } else if (!strcmp((char *) loglevel_type,
-               config_loglevel_type_range)) {
-               ret = LTTNG_EVENT_LOGLEVEL_RANGE;
-       } else if (!strcmp((char *) loglevel_type,
-               config_loglevel_type_single)) {
-               ret = LTTNG_EVENT_LOGLEVEL_SINGLE;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-/*
- * Return the context type or -1 on error.
- */
-static
-int get_context_type(xmlChar *context_type)
-{
-       int ret;
-
-       if (!context_type) {
-               goto error;
-       }
-
-       if (!strcmp((char *) context_type, config_event_context_pid)) {
-               ret = LTTNG_EVENT_CONTEXT_PID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_procname)) {
-               ret = LTTNG_EVENT_CONTEXT_PROCNAME;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_prio)) {
-               ret = LTTNG_EVENT_CONTEXT_PRIO;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_nice)) {
-               ret = LTTNG_EVENT_CONTEXT_NICE;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vpid)) {
-               ret = LTTNG_EVENT_CONTEXT_VPID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_tid)) {
-               ret = LTTNG_EVENT_CONTEXT_TID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vtid)) {
-               ret = LTTNG_EVENT_CONTEXT_VTID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_ppid)) {
-               ret = LTTNG_EVENT_CONTEXT_PPID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vppid)) {
-               ret = LTTNG_EVENT_CONTEXT_VPPID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_pthread_id)) {
-               ret = LTTNG_EVENT_CONTEXT_PTHREAD_ID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_hostname)) {
-               ret = LTTNG_EVENT_CONTEXT_HOSTNAME;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_ip)) {
-               ret = LTTNG_EVENT_CONTEXT_IP;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_interruptible)) {
-               ret = LTTNG_EVENT_CONTEXT_INTERRUPTIBLE;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_preemptible)) {
-               ret = LTTNG_EVENT_CONTEXT_PREEMPTIBLE;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_need_reschedule)) {
-               ret = LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_migratable)) {
-               ret = LTTNG_EVENT_CONTEXT_MIGRATABLE;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_callstack_user)) {
-               ret = LTTNG_EVENT_CONTEXT_CALLSTACK_USER;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_callstack_kernel)) {
-               ret = LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_cgroup_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_CGROUP_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_ipc_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_IPC_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_mnt_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_MNT_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_net_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_NET_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_pid_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_PID_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_time_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_TIME_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_user_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_USER_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_uts_ns)) {
-               ret = LTTNG_EVENT_CONTEXT_UTS_NS;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_uid)) {
-               ret = LTTNG_EVENT_CONTEXT_UID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_euid)) {
-               ret = LTTNG_EVENT_CONTEXT_EUID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_suid)) {
-               ret = LTTNG_EVENT_CONTEXT_SUID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_gid)) {
-               ret = LTTNG_EVENT_CONTEXT_GID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_egid)) {
-               ret = LTTNG_EVENT_CONTEXT_EGID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_sgid)) {
-               ret = LTTNG_EVENT_CONTEXT_SGID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vuid)) {
-               ret = LTTNG_EVENT_CONTEXT_VUID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_veuid)) {
-               ret = LTTNG_EVENT_CONTEXT_VEUID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vsuid)) {
-               ret = LTTNG_EVENT_CONTEXT_VSUID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vgid)) {
-               ret = LTTNG_EVENT_CONTEXT_VGID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vegid)) {
-               ret = LTTNG_EVENT_CONTEXT_VEGID;
-       } else if (!strcmp((char *) context_type,
-               config_event_context_vsgid)) {
-               ret = LTTNG_EVENT_CONTEXT_VSGID;
-       } else {
-               goto error;
-       }
-
-       return ret;
-error:
-       return -1;
-}
-
-static
-int init_domain(xmlNodePtr domain_node, struct lttng_domain *domain)
-{
-       int ret;
-       xmlNodePtr node;
-
-       for (node = xmlFirstElementChild(domain_node); node;
-               node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name, config_element_type)) {
-                       /* domain type */
-                       xmlChar *node_content = xmlNodeGetContent(node);
-                       if (!node_content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = get_domain_type(node_content);
-                       free(node_content);
-                       if (ret < 0) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       domain->type = ret;
-               } else if (!strcmp((const char *) node->name,
-                       config_element_buffer_type)) {
-                       /* buffer type */
-                       xmlChar *node_content = xmlNodeGetContent(node);
-                       if (!node_content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = get_buffer_type(node_content);
-                       free(node_content);
-                       if (ret < 0) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       domain->buf_type = ret;
-               }
-       }
-       ret = 0;
-end:
-       return ret;
-}
-
-static
-int get_net_output_uris(xmlNodePtr net_output_node, char **control_uri,
-       char **data_uri)
-{
-       xmlNodePtr node;
-
-       for (node = xmlFirstElementChild(net_output_node); node;
-               node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name, config_element_control_uri)) {
-                       /* control_uri */
-                       *control_uri = (char *) xmlNodeGetContent(node);
-                       if (!*control_uri) {
-                               break;
-                       }
-               } else {
-                       /* data_uri */
-                       *data_uri = (char *) xmlNodeGetContent(node);
-                       if (!*data_uri) {
-                               break;
-                       }
-               }
-       }
-
-       return *control_uri || *data_uri ? 0 : -LTTNG_ERR_LOAD_INVALID_CONFIG;
-}
-
-static
-int process_consumer_output(xmlNodePtr consumer_output_node,
-       struct consumer_output *output)
-{
-       int ret;
-       xmlNodePtr node;
-
-       LTTNG_ASSERT(output);
-
-       for (node = xmlFirstElementChild(consumer_output_node); node;
-                       node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name, config_element_enabled)) {
-                       xmlChar *enabled_str = xmlNodeGetContent(node);
-
-                       /* enabled */
-                       if (!enabled_str) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = parse_bool(enabled_str, &output->enabled);
-                       free(enabled_str);
-                       if (ret) {
-                               goto end;
-                       }
-               } else {
-                       xmlNodePtr output_type_node;
-
-                       /* destination */
-                       output_type_node = xmlFirstElementChild(node);
-                       if (!output_type_node) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       if (!strcmp((const char *) output_type_node->name,
-                                       config_element_path)) {
-                               /* path */
-                               output->path = (char *) xmlNodeGetContent(output_type_node);
-                               if (!output->path) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-                       } else {
-                               /* net_output */
-                               ret = get_net_output_uris(output_type_node,
-                                               &output->control_uri, &output->data_uri);
-                               if (ret) {
-                                       goto end;
-                               }
-                       }
-               }
-       }
-       ret = 0;
-
-end:
-       if (ret) {
-               free(output->path);
-               free(output->control_uri);
-               free(output->data_uri);
-               memset(output, 0, sizeof(struct consumer_output));
-       }
-       return ret;
-}
-
-static
-int create_session_net_output(const char *name, const char *control_uri,
-               const char *data_uri)
-{
-       int ret;
-       struct lttng_handle *handle;
-       const char *uri = NULL;
-
-       LTTNG_ASSERT(name);
-
-       handle = lttng_create_handle(name, NULL);
-       if (!handle) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto end;
-       }
-
-       if (!control_uri || !data_uri) {
-               uri = control_uri ? control_uri : data_uri;
-               control_uri = uri;
-               data_uri = uri;
-       }
-
-       ret = lttng_set_consumer_url(handle, control_uri, data_uri);
-       lttng_destroy_handle(handle);
-end:
-       return ret;
-}
-
-static
-int create_snapshot_session(const char *session_name, xmlNodePtr output_node,
-               const struct config_load_session_override_attr *overrides)
-{
-       int ret;
-       xmlNodePtr node = NULL;
-       xmlNodePtr snapshot_output_list_node;
-       xmlNodePtr snapshot_output_node;
-
-       LTTNG_ASSERT(session_name);
-
-       ret = lttng_create_session_snapshot(session_name, NULL);
-       if (ret) {
-               goto end;
-       }
-
-       if (!output_node) {
-               goto end;
-       }
-
-       snapshot_output_list_node = xmlFirstElementChild(output_node);
-
-       /* Parse and create snapshot outputs */
-
-       for (snapshot_output_node =
-                       xmlFirstElementChild(snapshot_output_list_node);
-                       snapshot_output_node; snapshot_output_node =
-                       xmlNextElementSibling(snapshot_output_node)) {
-               char *name = NULL;
-               uint64_t max_size = UINT64_MAX;
-               struct consumer_output output = { 0 };
-               struct lttng_snapshot_output *snapshot_output = NULL;
-               const char *control_uri = NULL;
-               const char *data_uri = NULL;
-               const char *path = NULL;
-
-               for (node = xmlFirstElementChild(snapshot_output_node); node;
-                               node = xmlNextElementSibling(node)) {
-                       if (!strcmp((const char *) node->name,
-                               config_element_name)) {
-                               /* name */
-                               name = (char *) xmlNodeGetContent(node);
-                               if (!name) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto error_snapshot_output;
-                               }
-                       } else if (!strcmp((const char *) node->name,
-                               config_element_max_size)) {
-                               xmlChar *content = xmlNodeGetContent(node);
-
-                               /* max_size */
-                               if (!content) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto error_snapshot_output;
-                               }
-                               ret = parse_uint(content, &max_size);
-                               free(content);
-                               if (ret) {
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto error_snapshot_output;
-                               }
-                       } else {
-                               /* consumer_output */
-                               ret = process_consumer_output(node, &output);
-                               if (ret) {
-                                       goto error_snapshot_output;
-                               }
-                       }
-               }
-
-               control_uri = output.control_uri;
-               data_uri = output.data_uri;
-               path = output.path;
-
-               if (overrides) {
-                       if (overrides->path_url) {
-                               path = overrides->path_url;
-                               /* Control/data_uri are null */
-                               control_uri = NULL;
-                               data_uri = NULL;
-                       } else {
-                               if (overrides->ctrl_url) {
-                                       control_uri = overrides->ctrl_url;
-                                       /* path is null */
-                                       path = NULL;
-                               }
-                               if (overrides->data_url) {
-                                       data_uri = overrides->data_url;
-                                       /* path is null */
-                                       path = NULL;
-                               }
-                       }
-               }
-
-               snapshot_output = lttng_snapshot_output_create();
-               if (!snapshot_output) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto error_snapshot_output;
-               }
-
-               ret = lttng_snapshot_output_set_name(name, snapshot_output);
-               if (ret) {
-                       goto error_snapshot_output;
-               }
-
-               ret = lttng_snapshot_output_set_size(max_size, snapshot_output);
-               if (ret) {
-                       goto error_snapshot_output;
-               }
-
-               if (path) {
-                       ret = lttng_snapshot_output_set_ctrl_url(path,
-                                       snapshot_output);
-                       if (ret) {
-                               goto error_snapshot_output;
-                       }
-               } else {
-                       if (control_uri) {
-                               ret = lttng_snapshot_output_set_ctrl_url(control_uri,
-                                               snapshot_output);
-                               if (ret) {
-                                       goto error_snapshot_output;
-                               }
-                       }
-
-                       if (data_uri) {
-                               ret = lttng_snapshot_output_set_data_url(data_uri,
-                                               snapshot_output);
-                               if (ret) {
-                                       goto error_snapshot_output;
-                               }
-                       }
-               }
-
-               ret = lttng_snapshot_add_output(session_name, snapshot_output);
-error_snapshot_output:
-               free(name);
-               free(output.path);
-               free(output.control_uri);
-               free(output.data_uri);
-               lttng_snapshot_output_destroy(snapshot_output);
-               if (ret) {
-                       goto end;
-               }
-       }
-end:
-       return ret;
-}
-
-static
-int create_session(const char *name,
-       xmlNodePtr output_node,
-       uint64_t live_timer_interval,
-       const struct config_load_session_override_attr *overrides)
-{
-       int ret;
-       struct consumer_output output = { 0 };
-       xmlNodePtr consumer_output_node;
-       const char *control_uri = NULL;
-       const char *data_uri = NULL;
-       const char *path = NULL;
-
-       LTTNG_ASSERT(name);
-
-       if (output_node) {
-               consumer_output_node = xmlFirstElementChild(output_node);
-               if (!consumer_output_node) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               if (strcmp((const char *) consumer_output_node->name,
-                       config_element_consumer_output)) {
-                       WARN("Invalid output type, expected %s node",
-                               config_element_consumer_output);
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               ret = process_consumer_output(consumer_output_node, &output);
-               if (ret) {
-                       goto end;
-               }
-       }
-
-       control_uri = output.control_uri;
-       data_uri = output.data_uri;
-       path = output.path;
-
-       /* Check for override and apply them */
-       if (overrides) {
-               if (overrides->path_url) {
-                       path = overrides->path_url;
-                       /* control/data_uri are null */;
-                       control_uri = NULL;
-                       data_uri = NULL;
-               } else {
-                       if (overrides->ctrl_url) {
-                               control_uri = overrides->ctrl_url;
-                               /* path is null */
-                               path = NULL;
-                       }
-                       if (overrides->data_url) {
-                               data_uri = overrides->data_url;
-                               /* path is null */
-                               path = NULL;
-                       }
-               }
-       }
-
-
-       if (live_timer_interval != UINT64_MAX && !control_uri && !data_uri) {
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       if (control_uri || data_uri) {
-               /* network destination */
-               if (live_timer_interval && live_timer_interval != UINT64_MAX) {
-                       /*
-                        * URLs are provided for sure since the test above make sure that
-                        * with a live timer the data and control URIs are provided. So,
-                        * NULL is passed here and will be set right after.
-                        */
-                       ret = lttng_create_session_live(name, NULL, live_timer_interval);
-               } else {
-                       ret = lttng_create_session(name, NULL);
-               }
-               if (ret) {
-                       goto end;
-               }
-
-               ret = create_session_net_output(name, control_uri, data_uri);
-               if (ret) {
-                       goto end;
-               }
-
-       } else {
-               /* either local output or no output */
-               ret = lttng_create_session(name, path);
-               if (ret) {
-                       goto end;
-               }
-       }
-end:
-       free(output.path);
-       free(output.control_uri);
-       free(output.data_uri);
-       return ret;
-}
-
-static
-struct lttng_userspace_probe_location *
-process_userspace_probe_function_attribute_node(
-               xmlNodePtr attribute_node)
-{
-       xmlNodePtr function_attribute_node;
-       char *function_name = NULL, *binary_path = NULL;
-       struct lttng_userspace_probe_location *location = NULL;
-       struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
-
-       /*
-        * Process userspace probe location function attributes. The order of
-        * the fields are not guaranteed so we need to iterate over all fields
-        * and check at the end if everything we need for this location type is
-        * there.
-        */
-       for (function_attribute_node =
-                       xmlFirstElementChild(attribute_node);
-                       function_attribute_node;
-                       function_attribute_node = xmlNextElementSibling(
-                               function_attribute_node)) {
-               /* Handle function name, binary path and lookup method. */
-               if (!strcmp((const char *) function_attribute_node->name,
-                                       config_element_userspace_probe_function_location_function_name)) {
-                       function_name = (char *) xmlNodeGetContent(function_attribute_node);
-                       if (!function_name) {
-                               goto error;
-                       }
-               } else if (!strcmp((const char *) function_attribute_node->name,
-                                       config_element_userspace_probe_location_binary_path)) {
-                       binary_path = (char *) xmlNodeGetContent(function_attribute_node);
-                       if (!binary_path) {
-                               goto error;
-                       }
-               } else if (!strcmp((const char *) function_attribute_node->name,
-                                       config_element_userspace_probe_lookup)) {
-                       char *lookup_method_name;
-
-                       lookup_method_name = (char *) xmlNodeGetContent(
-                                       function_attribute_node);
-                       if (!lookup_method_name) {
-                               goto error;
-                       }
-
-                       /*
-                        * function_default lookup method defaults to
-                        * function_elf lookup method at the moment.
-                        */
-                       if (!strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_elf)
-                                       || !strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_default)) {
-                               lookup_method = lttng_userspace_probe_location_lookup_method_function_elf_create();
-                               if (!lookup_method) {
-                                       PERROR("Error creating function default/ELF lookup method");
-                               }
-                       } else {
-                               WARN("Unknown function lookup method");
-                       }
-
-                       free(lookup_method_name);
-                       if (!lookup_method) {
-                               goto error;
-                       }
-               } else {
-                       goto error;
-               }
-
-               /* Check if all the necessary fields were found. */
-               if (binary_path && function_name && lookup_method) {
-                       /* Ownership of lookup_method is transferred. */
-                       location =
-                               lttng_userspace_probe_location_function_create(
-                                               binary_path, function_name,
-                                               lookup_method);
-                       lookup_method = NULL;
-                       goto error;
-               }
-       }
-error:
-       lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
-       free(binary_path);
-       free(function_name);
-       return location;
-}
-
-static
-struct lttng_userspace_probe_location *
-process_userspace_probe_tracepoint_attribute_node(
-               xmlNodePtr attribute_node)
-{
-       xmlNodePtr tracepoint_attribute_node;
-       char *probe_name = NULL, *provider_name = NULL, *binary_path = NULL;
-       struct lttng_userspace_probe_location *location = NULL;
-       struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
-
-       /*
-        * Process userspace probe location tracepoint attributes. The order of
-        * the fields are not guaranteed so we need to iterate over all fields
-        * and check at the end if everything we need for this location type is
-        * there.
-        */
-       for (tracepoint_attribute_node =
-               xmlFirstElementChild(attribute_node); tracepoint_attribute_node;
-               tracepoint_attribute_node = xmlNextElementSibling(
-                               tracepoint_attribute_node)) {
-               if (!strcmp((const char *) tracepoint_attribute_node->name,
-                                       config_element_userspace_probe_tracepoint_location_probe_name)) {
-                       probe_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
-                       if (!probe_name) {
-                               goto error;
-                       }
-               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
-                                       config_element_userspace_probe_tracepoint_location_provider_name)) {
-                       provider_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
-                       if (!provider_name) {
-                               goto error;
-                       }
-               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
-                                       config_element_userspace_probe_location_binary_path)) {
-                       binary_path = (char *) xmlNodeGetContent(tracepoint_attribute_node);
-                       if (!binary_path) {
-                               goto error;
-                       }
-               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
-                                       config_element_userspace_probe_lookup)) {
-                       char *lookup_method_name;
-
-                       lookup_method_name = (char *) xmlNodeGetContent(
-                                       tracepoint_attribute_node);
-                       if (!lookup_method_name) {
-                               goto error;
-                       }
-
-                       if (!strcmp(lookup_method_name,
-                                               config_element_userspace_probe_lookup_tracepoint_sdt)) {
-                               lookup_method =
-                                       lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create();
-                               if (!lookup_method) {
-                                       PERROR("Error creating tracepoint SDT lookup method");
-                               }
-                       } else {
-                               WARN("Unknown tracepoint lookup method");
-                       }
-
-                       free(lookup_method_name);
-                       if (!lookup_method) {
-                               goto error;
-                       }
-               } else {
-                       WARN("Unknown tracepoint attribute");
-                       goto error;
-               }
-
-               /* Check if all the necessary fields were found. */
-               if (binary_path && provider_name && probe_name && lookup_method) {
-                       /* Ownership of lookup_method is transferred. */
-                       location =
-                               lttng_userspace_probe_location_tracepoint_create(
-                                               binary_path, provider_name,
-                                               probe_name, lookup_method);
-                       lookup_method = NULL;
-                       goto error;
-               }
-       }
-error:
-       lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
-       free(binary_path);
-       free(provider_name);
-       free(probe_name);
-       return location;
-}
-
-static
-int process_probe_attribute_node(xmlNodePtr probe_attribute_node,
-       struct lttng_event_probe_attr *attr)
-{
-       int ret;
-
-       LTTNG_ASSERT(probe_attribute_node);
-       LTTNG_ASSERT(attr);
-
-       if (!strcmp((const char *) probe_attribute_node->name,
-               config_element_address)) {
-               xmlChar *content;
-               uint64_t addr = 0;
-
-               /* addr */
-               content = xmlNodeGetContent(probe_attribute_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &addr);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               attr->addr = addr;
-       } else if (!strcmp((const char *) probe_attribute_node->name,
-               config_element_offset)) {
-               xmlChar *content;
-               uint64_t offset = 0;
-
-               /* offset */
-               content = xmlNodeGetContent(probe_attribute_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &offset);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               attr->offset = offset;
-       } else if (!strcmp((const char *) probe_attribute_node->name,
-               config_element_symbol_name)) {
-               xmlChar *content;
-
-               /* symbol_name */
-               content = xmlNodeGetContent(probe_attribute_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = lttng_strncpy(attr->symbol_name,
-                               (const char *) content,
-                               LTTNG_SYMBOL_NAME_LEN);
-               if (ret == -1) {
-                       ERR("symbol name \"%s\"'s length (%zu) exceeds the maximal permitted length (%d) in session configuration",
-                                       (const char *) content,
-                                       strlen((const char *) content),
-                                       LTTNG_SYMBOL_NAME_LEN);
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       free(content);
-                       goto end;
-               }
-               free(content);
-       }
-       ret = 0;
-end:
-       return ret;
-}
-
-static
-int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
-       const char *channel_name, const enum process_event_node_phase phase)
-{
-       int ret = 0, i;
-       xmlNodePtr node;
-       struct lttng_event *event;
-       char **exclusions = NULL;
-       unsigned long exclusion_count = 0;
-       char *filter_expression = NULL;
-
-       LTTNG_ASSERT(event_node);
-       LTTNG_ASSERT(handle);
-       LTTNG_ASSERT(channel_name);
-
-       event = lttng_event_create();
-       if (!event) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto end;
-       }
-
-       /* Initialize default log level which varies by domain */
-       switch (handle->domain.type)
-       {
-       case LTTNG_DOMAIN_JUL:
-               event->loglevel = LTTNG_LOGLEVEL_JUL_ALL;
-               break;
-       case LTTNG_DOMAIN_LOG4J:
-               event->loglevel = LTTNG_LOGLEVEL_LOG4J_ALL;
-               break;
-       case LTTNG_DOMAIN_PYTHON:
-               event->loglevel = LTTNG_LOGLEVEL_PYTHON_DEBUG;
-               break;
-       case LTTNG_DOMAIN_UST:
-       case LTTNG_DOMAIN_KERNEL:
-               event->loglevel = LTTNG_LOGLEVEL_DEBUG;
-               break;
-       default:
-               abort();
-       }
-
-       for (node = xmlFirstElementChild(event_node); node;
-               node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name, config_element_name)) {
-                       xmlChar *content;
-
-                       /* name */
-                       content = xmlNodeGetContent(node);
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = lttng_strncpy(event->name,
-                                       (const char *) content,
-                                       LTTNG_SYMBOL_NAME_LEN);
-                       if (ret == -1) {
-                               WARN("Event \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
-                                               (const char *) content,
-                                               strlen((const char *) content),
-                                               LTTNG_SYMBOL_NAME_LEN);
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               free(content);
-                               goto end;
-                       }
-                       free(content);
-               } else if (!strcmp((const char *) node->name,
-                       config_element_enabled)) {
-                       xmlChar *content = xmlNodeGetContent(node);
-
-                       /* enabled */
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = parse_bool(content, &event->enabled);
-                       free(content);
-                       if (ret) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-               } else if (!strcmp((const char *) node->name,
-                       config_element_type)) {
-                       xmlChar *content = xmlNodeGetContent(node);
-
-                       /* type */
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = get_event_type(content);
-                       free(content);
-                       if (ret < 0) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       event->type = ret;
-               } else if (!strcmp((const char *) node->name,
-                       config_element_loglevel_type)) {
-                       xmlChar *content = xmlNodeGetContent(node);
-
-                       /* loglevel_type */
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = get_loglevel_type(content);
-                       free(content);
-                       if (ret < 0) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       event->loglevel_type = ret;
-               } else if (!strcmp((const char *) node->name,
-                       config_element_loglevel)) {
-                       xmlChar *content;
-                       int64_t loglevel = 0;
-
-                       /* loglevel */
-                       content = xmlNodeGetContent(node);
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = parse_int(content, &loglevel);
-                       free(content);
-                       if (ret) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       if (loglevel > INT_MAX || loglevel < INT_MIN) {
-                               WARN("loglevel out of range.");
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       event->loglevel = loglevel;
-               } else if (!strcmp((const char *) node->name,
-                       config_element_filter)) {
-                       xmlChar *content =
-                               xmlNodeGetContent(node);
-
-                       /* filter */
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       free(filter_expression);
-                       filter_expression = strdup((char *) content);
-                       free(content);
-                       if (!filter_expression) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-               } else if (!strcmp((const char *) node->name,
-                       config_element_exclusions)) {
-                       xmlNodePtr exclusion_node;
-                       int exclusion_index = 0;
-
-                       /* exclusions */
-                       if (exclusions) {
-                               /*
-                                * Exclusions has already been initialized,
-                                * invalid file.
-                                */
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       exclusion_count = xmlChildElementCount(node);
-                       if (!exclusion_count) {
-                               continue;
-                       }
-
-                       exclusions = zmalloc(exclusion_count * sizeof(char *));
-                       if (!exclusions) {
-                               exclusion_count = 0;
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       for (exclusion_node = xmlFirstElementChild(node); exclusion_node;
-                                       exclusion_node = xmlNextElementSibling(exclusion_node)) {
-                               xmlChar *content =
-                                       xmlNodeGetContent(exclusion_node);
-
-                               if (!content) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-
-                               exclusions[exclusion_index] = strdup((const char *) content);
-                               free(content);
-                               if (!exclusions[exclusion_index]) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-                               exclusion_index++;
-                       }
-
-                       event->exclusion = 1;
-               } else if (!strcmp((const char *) node->name,
-                       config_element_attributes)) {
-                       xmlNodePtr attribute_node = xmlFirstElementChild(node);
-
-                       /* attributes */
-                       if (!attribute_node) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       if (!strcmp((const char *) attribute_node->name,
-                                               config_element_probe_attributes)) {
-                               xmlNodePtr probe_attribute_node;
-
-                               /* probe_attributes */
-                               for (probe_attribute_node =
-                                       xmlFirstElementChild(attribute_node); probe_attribute_node;
-                                       probe_attribute_node = xmlNextElementSibling(
-                                                       probe_attribute_node)) {
-
-                                       ret = process_probe_attribute_node(probe_attribute_node,
-                                                       &event->attr.probe);
-                                       if (ret) {
-                                               goto end;
-                                       }
-                               }
-                       } else if (!strcmp((const char *) attribute_node->name,
-                                               config_element_function_attributes)) {
-                               size_t sym_len;
-                               xmlChar *content;
-                               xmlNodePtr symbol_node = xmlFirstElementChild(attribute_node);
-
-                               /* function_attributes */
-                               content = xmlNodeGetContent(symbol_node);
-                               if (!content) {
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               sym_len = strlen((char *) content);
-                               if (sym_len >= LTTNG_SYMBOL_NAME_LEN) {
-                                       WARN("Function name too long.");
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       free(content);
-                                       goto end;
-                               }
-
-                               ret = lttng_strncpy(
-                                               event->attr.ftrace.symbol_name,
-                                               (char *) content, sym_len);
-                               if (ret == -1) {
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       free(content);
-                                       goto end;
-                               }
-                               free(content);
-                       } else if (!strcmp((const char *) attribute_node->name,
-                                               config_element_userspace_probe_tracepoint_attributes)) {
-                               struct lttng_userspace_probe_location *location;
-
-                               location = process_userspace_probe_tracepoint_attribute_node(attribute_node);
-                               if (!location) {
-                                       WARN("Error processing userspace probe tracepoint attribute");
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-                               ret = lttng_event_set_userspace_probe_location(
-                                               event, location);
-                               if (ret) {
-                                       WARN("Error setting userspace probe location field");
-                                       lttng_userspace_probe_location_destroy(
-                                                       location);
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-                       } else if (!strcmp((const char *) attribute_node->name,
-                                               config_element_userspace_probe_function_attributes)) {
-                               struct lttng_userspace_probe_location *location;
-
-                               location =
-                                       process_userspace_probe_function_attribute_node(
-                                                       attribute_node);
-                               if (!location) {
-                                       WARN("Error processing userspace probe function attribute");
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               ret = lttng_event_set_userspace_probe_location(
-                                               event, location);
-                               if (ret) {
-                                       WARN("Error setting userspace probe location field");
-                                       lttng_userspace_probe_location_destroy(
-                                                       location);
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-                       } else {
-                               /* Unknown event attribute. */
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-               }
-       }
-
-       if ((event->enabled && phase == ENABLE) || phase == CREATION) {
-               ret = lttng_enable_event_with_exclusions(handle, event, channel_name,
-                               filter_expression, exclusion_count, exclusions);
-               if (ret < 0) {
-                       WARN("Enabling event (name:%s) on load failed.", event->name);
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       }
-       ret = 0;
-end:
-       for (i = 0; i < exclusion_count; i++) {
-               free(exclusions[i]);
-       }
-
-       lttng_event_destroy(event);
-       free(exclusions);
-       free(filter_expression);
-       return ret;
-}
-
-static
-int process_events_node(xmlNodePtr events_node, struct lttng_handle *handle,
-       const char *channel_name)
-{
-       int ret = 0;
-       struct lttng_event event;
-       xmlNodePtr node;
-
-       LTTNG_ASSERT(events_node);
-       LTTNG_ASSERT(handle);
-       LTTNG_ASSERT(channel_name);
-
-       for (node = xmlFirstElementChild(events_node); node;
-               node = xmlNextElementSibling(node)) {
-               ret = process_event_node(node, handle, channel_name, CREATION);
-               if (ret) {
-                       goto end;
-               }
-       }
-
-       /*
-        * Disable all events to enable only the necessary events.
-        * Limitations regarding lttng_disable_events and tuple descriptor
-        * force this approach.
-        */
-       memset(&event, 0, sizeof(event));
-       event.loglevel = -1;
-       event.type = LTTNG_EVENT_ALL;
-       ret = lttng_disable_event_ext(handle, &event, channel_name, NULL);
-       if (ret) {
-               goto end;
-       }
-
-       for (node = xmlFirstElementChild(events_node); node;
-                       node = xmlNextElementSibling(node)) {
-               ret = process_event_node(node, handle, channel_name, ENABLE);
-               if (ret) {
-                       goto end;
-               }
-       }
-
-end:
-       return ret;
-}
-
-static
-int process_channel_attr_node(xmlNodePtr attr_node,
-               struct lttng_channel *channel, xmlNodePtr *contexts_node,
-               xmlNodePtr *events_node)
-{
-       int ret;
-
-       LTTNG_ASSERT(attr_node);
-       LTTNG_ASSERT(channel);
-       LTTNG_ASSERT(contexts_node);
-       LTTNG_ASSERT(events_node);
-
-       if (!strcmp((const char *) attr_node->name, config_element_name)) {
-               xmlChar *content;
-
-               /* name */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = lttng_strncpy(channel->name,
-                               (const char *) content,
-                               LTTNG_SYMBOL_NAME_LEN);
-               if (ret == -1) {
-                       WARN("Channel \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
-                                       (const char *) content,
-                                       strlen((const char *) content),
-                                       LTTNG_SYMBOL_NAME_LEN);
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       free(content);
-                       goto end;
-               }
-               free(content);
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_enabled)) {
-               xmlChar *content;
-               int enabled;
-
-               /* enabled */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_bool(content, &enabled);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->enabled = enabled;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_overwrite_mode)) {
-               xmlChar *content;
-
-               /* overwrite_mode */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = get_overwrite_mode(content);
-               free(content);
-               if (ret < 0) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->attr.overwrite = ret;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_subbuf_size)) {
-               xmlChar *content;
-
-               /* subbuffer_size */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &channel->attr.subbuf_size);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_num_subbuf)) {
-               xmlChar *content;
-
-               /* subbuffer_count */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &channel->attr.num_subbuf);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_switch_timer_interval)) {
-               xmlChar *content;
-               uint64_t switch_timer_interval = 0;
-
-               /* switch_timer_interval */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &switch_timer_interval);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               if (switch_timer_interval > UINT_MAX) {
-                       WARN("switch_timer_interval out of range.");
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->attr.switch_timer_interval =
-                       switch_timer_interval;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_read_timer_interval)) {
-               xmlChar *content;
-               uint64_t read_timer_interval = 0;
-
-               /* read_timer_interval */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &read_timer_interval);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               if (read_timer_interval > UINT_MAX) {
-                       WARN("read_timer_interval out of range.");
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->attr.read_timer_interval =
-                       read_timer_interval;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_output_type)) {
-               xmlChar *content;
-
-               /* output_type */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = get_output_type(content);
-               free(content);
-               if (ret < 0) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->attr.output = ret;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_tracefile_size)) {
-               xmlChar *content;
-
-               /* tracefile_size */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &channel->attr.tracefile_size);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_tracefile_count)) {
-               xmlChar *content;
-
-               /* tracefile_count */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &channel->attr.tracefile_count);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_live_timer_interval)) {
-               xmlChar *content;
-               uint64_t live_timer_interval = 0;
-
-               /* live_timer_interval */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &live_timer_interval);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               if (live_timer_interval > UINT_MAX) {
-                       WARN("live_timer_interval out of range.");
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               channel->attr.live_timer_interval =
-                       live_timer_interval;
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_monitor_timer_interval)) {
-               xmlChar *content;
-               uint64_t monitor_timer_interval = 0;
-
-               /* monitor_timer_interval */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_uint(content, &monitor_timer_interval);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               ret = lttng_channel_set_monitor_timer_interval(channel,
-                       monitor_timer_interval);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_blocking_timeout)) {
-               xmlChar *content;
-               int64_t blocking_timeout = 0;
-
-               /* blocking_timeout */
-               content = xmlNodeGetContent(attr_node);
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = parse_int(content, &blocking_timeout);
-               free(content);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               ret = lttng_channel_set_blocking_timeout(channel,
-                       blocking_timeout);
-               if (ret) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-       } else if (!strcmp((const char *) attr_node->name,
-                       config_element_events)) {
-               /* events */
-               *events_node = attr_node;
-       } else {
-               /* contexts */
-               *contexts_node = attr_node;
-       }
-       ret = 0;
-end:
-       return ret;
-}
-
-static
-int process_context_node(xmlNodePtr context_node,
-       struct lttng_handle *handle, const char *channel_name)
-{
-       int ret;
-       struct lttng_event_context context;
-       xmlNodePtr context_child_node = xmlFirstElementChild(context_node);
-
-       LTTNG_ASSERT(handle);
-       LTTNG_ASSERT(channel_name);
-
-       if (!context_child_node) {
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       memset(&context, 0, sizeof(context));
-
-       if (!strcmp((const char *) context_child_node->name,
-               config_element_type)) {
-               /* type */
-               xmlChar *content = xmlNodeGetContent(context_child_node);
-
-               if (!content) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = get_context_type(content);
-               free(content);
-               if (ret < 0) {
-                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                       goto end;
-               }
-
-               context.ctx = ret;
-       } else if (!strcmp((const char *) context_child_node->name,
-               config_element_context_perf)) {
-               /* perf */
-               xmlNodePtr perf_attr_node;
-
-               context.ctx = handle->domain.type == LTTNG_DOMAIN_KERNEL ?
-                       LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER :
-                       LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER;
-               for (perf_attr_node = xmlFirstElementChild(context_child_node);
-                       perf_attr_node; perf_attr_node =
-                               xmlNextElementSibling(perf_attr_node)) {
-                       if (!strcmp((const char *) perf_attr_node->name,
-                               config_element_type)) {
-                               xmlChar *content;
-                               uint64_t type = 0;
-
-                               /* type */
-                               content = xmlNodeGetContent(perf_attr_node);
-                               if (!content) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-
-                               ret = parse_uint(content, &type);
-                               free(content);
-                               if (ret) {
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               if (type > UINT32_MAX) {
-                                       WARN("perf context type out of range.");
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               context.u.perf_counter.type = type;
-                       } else if (!strcmp((const char *) perf_attr_node->name,
-                               config_element_config)) {
-                               xmlChar *content;
-                               uint64_t config = 0;
-
-                               /* config */
-                               content = xmlNodeGetContent(perf_attr_node);
-                               if (!content) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-
-                               ret = parse_uint(content, &config);
-                               free(content);
-                               if (ret) {
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               context.u.perf_counter.config = config;
-                       } else if (!strcmp((const char *) perf_attr_node->name,
-                               config_element_name)) {
-                               xmlChar *content;
-
-                               /* name */
-                               content = xmlNodeGetContent(perf_attr_node);
-                               if (!content) {
-                                       ret = -LTTNG_ERR_NOMEM;
-                                       goto end;
-                               }
-
-                               ret = lttng_strncpy(context.u.perf_counter.name,
-                                               (const char *) content,
-                                               LTTNG_SYMBOL_NAME_LEN);
-                               if (ret == -1) {
-                                       WARN("Perf counter \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
-                                                       (const char *) content,
-                                                       strlen((const char *) content),
-                                                       LTTNG_SYMBOL_NAME_LEN);
-                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       free(content);
-                                       goto end;
-                               }
-                               free(content);
-                       }
-               }
-       } else if (!strcmp((const char *) context_child_node->name,
-               config_element_context_app)) {
-               /* application context */
-               xmlNodePtr app_ctx_node;
-
-               context.ctx = LTTNG_EVENT_CONTEXT_APP_CONTEXT;
-               for (app_ctx_node = xmlFirstElementChild(context_child_node);
-                               app_ctx_node; app_ctx_node =
-                               xmlNextElementSibling(app_ctx_node)) {
-                       xmlChar *content;
-                       char **target = strcmp(
-                               (const char *) app_ctx_node->name,
-                               config_element_context_app_provider_name) == 0 ?
-                                       &context.u.app_ctx.provider_name :
-                                       &context.u.app_ctx.ctx_name;
-
-                       content = xmlNodeGetContent(app_ctx_node);
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       *target = (char *) content;
-               }
-       } else {
-               /* Unrecognized context type */
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       ret = lttng_add_context(handle, &context, NULL, channel_name);
-       if (context.ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
-               free(context.u.app_ctx.provider_name);
-               free(context.u.app_ctx.ctx_name);
-       }
-end:
-       return ret;
-}
-
-static
-int process_contexts_node(xmlNodePtr contexts_node,
-       struct lttng_handle *handle, const char *channel_name)
-{
-       int ret = 0;
-       xmlNodePtr context_node;
-
-       for (context_node = xmlFirstElementChild(contexts_node); context_node;
-                       context_node = xmlNextElementSibling(context_node)) {
-               ret = process_context_node(context_node, handle, channel_name);
-               if (ret) {
-                       goto end;
-               }
-       }
-end:
-       return ret;
-}
-
-static int get_tracker_elements(enum lttng_process_attr process_attr,
-               const char **element_id_tracker,
-               const char **element_value_type,
-               const char **element_value,
-               const char **element_value_alias,
-               const char **element_name)
-{
-       int ret = 0;
-
-       switch (process_attr) {
-       case LTTNG_PROCESS_ATTR_PROCESS_ID:
-               *element_id_tracker = config_element_process_attr_tracker_pid;
-               *element_value_type = config_element_process_attr_pid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = config_element_process_attr_id;
-               *element_name = NULL;
-               break;
-       case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
-               *element_id_tracker = config_element_process_attr_tracker_vpid;
-               *element_value_type = config_element_process_attr_vpid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = NULL;
-               *element_name = NULL;
-               break;
-       case LTTNG_PROCESS_ATTR_USER_ID:
-               *element_id_tracker = config_element_process_attr_tracker_uid;
-               *element_value_type = config_element_process_attr_uid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = NULL;
-               *element_name = config_element_name;
-               break;
-       case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
-               *element_id_tracker = config_element_process_attr_tracker_vuid;
-               *element_value_type = config_element_process_attr_vuid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = NULL;
-               *element_name = config_element_name;
-               break;
-       case LTTNG_PROCESS_ATTR_GROUP_ID:
-               *element_id_tracker = config_element_process_attr_tracker_gid;
-               *element_value_type = config_element_process_attr_gid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = NULL;
-               *element_name = config_element_name;
-               break;
-       case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
-               *element_id_tracker = config_element_process_attr_tracker_vgid;
-               *element_value_type = config_element_process_attr_vgid_value;
-               *element_value = config_element_process_attr_id;
-               *element_value_alias = NULL;
-               *element_name = config_element_name;
-               break;
-       default:
-               ret = LTTNG_ERR_INVALID;
-       }
-       return ret;
-}
-
-static int process_legacy_pid_tracker_node(
-               xmlNodePtr trackers_node, struct lttng_handle *handle)
-{
-       int ret = 0, child_count;
-       xmlNodePtr targets_node = NULL;
-       xmlNodePtr node;
-       const char *element_id_tracker;
-       const char *element_target_id;
-       const char *element_id;
-       const char *element_id_alias;
-       const char *element_name;
-       enum lttng_error_code tracker_handle_ret_code;
-       struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
-       enum lttng_process_attr_tracker_handle_status status;
-       const enum lttng_process_attr process_attr =
-                       handle->domain.type == LTTNG_DOMAIN_UST ?
-                                       LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID :
-                                       LTTNG_PROCESS_ATTR_PROCESS_ID;
-
-       LTTNG_ASSERT(handle);
-
-       tracker_handle_ret_code = lttng_session_get_tracker_handle(
-                       handle->session_name, handle->domain.type,
-                       process_attr,
-                       &tracker_handle);
-       if (tracker_handle_ret_code != LTTNG_OK) {
-               ret = LTTNG_ERR_INVALID;
-               goto end;
-       }
-
-       ret = get_tracker_elements(process_attr, &element_id_tracker,
-                       &element_target_id, &element_id, &element_id_alias,
-                       &element_name);
-       if (ret) {
-               goto end;
-       }
-
-       /* Get the targets node */
-       for (node = xmlFirstElementChild(trackers_node); node;
-                       node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name,
-                               config_element_tracker_targets_legacy)) {
-                       targets_node = node;
-                       break;
-               }
-       }       
-
-       if (!targets_node) {
-               ret = LTTNG_ERR_INVALID;
-               goto end;
-       }
-
-       /* Go through all id target node */
-       child_count = xmlChildElementCount(targets_node);
-       status = lttng_process_attr_tracker_handle_set_tracking_policy(
-                       tracker_handle,
-                       child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
-                                          LTTNG_TRACKING_POLICY_INCLUDE_SET);
-       if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
-               ret = LTTNG_ERR_UNK;
-               goto end;
-       }
-
-       /* Add all tracked values. */
-       for (node = xmlFirstElementChild(targets_node); node;
-                       node = xmlNextElementSibling(node)) {
-               xmlNodePtr pid_target_node = node;
-
-               /* get pid_target node and track it */
-               for (node = xmlFirstElementChild(pid_target_node); node;
-                               node = xmlNextElementSibling(node)) {
-                       if (!strcmp((const char *) node->name,
-                                           config_element_tracker_pid_legacy)) {
-                               int64_t id;
-                               xmlChar *content = xmlNodeGetContent(node);
-
-                               if (!content) {
-                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               ret = parse_int(content, &id);
-                               free(content);
-                               if (ret) {
-                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               switch (process_attr) {
-                               case LTTNG_PROCESS_ATTR_PROCESS_ID:
-                                       status = lttng_process_attr_process_id_tracker_handle_add_pid(
-                                                       tracker_handle,
-                                                       (pid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
-                                       status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
-                                                       tracker_handle,
-                                                       (pid_t) id);
-                                       break;
-                               default:
-                                       ret = LTTNG_ERR_INVALID;
-                                       goto end;
-                               }
-                       }
-                       switch (status) {
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
-                               continue;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
-                               ret = LTTNG_ERR_INVALID;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
-                               ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
-                               ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
-                       default:
-                               ret = LTTNG_ERR_UNK;
-                               goto end;
-                       }
-               }
-               node = pid_target_node;
-       }
-
-end:
-       lttng_process_attr_tracker_handle_destroy(tracker_handle);
-       return ret;
- }
-
-static int process_id_tracker_node(xmlNodePtr id_tracker_node,
-               struct lttng_handle *handle,
-               enum lttng_process_attr process_attr)
-{
-       int ret = 0, child_count;
-       xmlNodePtr values_node = NULL;
-       xmlNodePtr node;
-       const char *element_id_tracker;
-       const char *element_target_id;
-       const char *element_id;
-       const char *element_id_alias;
-       const char *element_name;
-       enum lttng_error_code tracker_handle_ret_code;
-       struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
-       enum lttng_process_attr_tracker_handle_status status;
-
-       LTTNG_ASSERT(handle);
-       LTTNG_ASSERT(id_tracker_node);
-
-       tracker_handle_ret_code = lttng_session_get_tracker_handle(
-                       handle->session_name, handle->domain.type, process_attr,
-                       &tracker_handle);
-       if (tracker_handle_ret_code != LTTNG_OK) {
-               ret = LTTNG_ERR_INVALID;
-               goto end;
-       }
-
-       ret = get_tracker_elements(process_attr, &element_id_tracker,
-                       &element_target_id, &element_id, &element_id_alias,
-                       &element_name);
-       if (ret) {
-               goto end;
-       }
-
-       /* get the values node */
-       for (node = xmlFirstElementChild(id_tracker_node); node;
-                       node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name,
-                               config_element_process_attr_values)) {
-                       values_node = node;
-                       break;
-               }
-       }
-
-       if (!values_node) {
-               ret = LTTNG_ERR_INVALID;
-               goto end;
-       }
-
-       /* Go through all id target node */
-       child_count = xmlChildElementCount(values_node);
-       status = lttng_process_attr_tracker_handle_set_tracking_policy(
-                       tracker_handle,
-                       child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
-                                          LTTNG_TRACKING_POLICY_INCLUDE_SET);
-       if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
-               ret = LTTNG_ERR_UNK;
-               goto end;
-       }
-
-       /* Add all tracked values. */
-       for (node = xmlFirstElementChild(values_node); node;
-                       node = xmlNextElementSibling(node)) {
-               xmlNodePtr id_target_node = node;
-
-               /* get id node and track it */
-               for (node = xmlFirstElementChild(id_target_node); node;
-                               node = xmlNextElementSibling(node)) {
-                       if (!strcmp((const char *) node->name, element_id) ||
-                                       (element_id_alias &&
-                                                       !strcmp((const char *) node->name,
-                                                                       element_id_alias))) {
-                               int64_t id;
-                               xmlChar *content = xmlNodeGetContent(node);
-
-                               if (!content) {
-                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               ret = parse_int(content, &id);
-                               free(content);
-                               if (ret) {
-                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               switch (process_attr) {
-                               case LTTNG_PROCESS_ATTR_PROCESS_ID:
-                                       status = lttng_process_attr_process_id_tracker_handle_add_pid(
-                                                       tracker_handle,
-                                                       (pid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
-                                       status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
-                                                       tracker_handle,
-                                                       (pid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_USER_ID:
-                                       status = lttng_process_attr_user_id_tracker_handle_add_uid(
-                                                       tracker_handle,
-                                                       (uid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
-                                       status = lttng_process_attr_virtual_user_id_tracker_handle_add_uid(
-                                                       tracker_handle,
-                                                       (uid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_GROUP_ID:
-                                       status = lttng_process_attr_group_id_tracker_handle_add_gid(
-                                                       tracker_handle,
-                                                       (gid_t) id);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
-                                       status = lttng_process_attr_virtual_group_id_tracker_handle_add_gid(
-                                                       tracker_handle,
-                                                       (gid_t) id);
-                                       break;
-                               default:
-                                       ret = LTTNG_ERR_INVALID;
-                                       goto end;
-                               }
-                       } else if (element_name &&
-                                       !strcmp((const char *) node->name,
-                                                       element_name)) {
-                               xmlChar *content = xmlNodeGetContent(node);
-
-                               if (!content) {
-                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                       goto end;
-                               }
-
-                               switch (process_attr) {
-                               case LTTNG_PROCESS_ATTR_USER_ID:
-                                       status = lttng_process_attr_user_id_tracker_handle_add_user_name(
-                                                       tracker_handle,
-                                                       (const char *) content);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
-                                       status = lttng_process_attr_virtual_user_id_tracker_handle_add_user_name(
-                                                       tracker_handle,
-                                                       (const char *) content);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_GROUP_ID:
-                                       status = lttng_process_attr_group_id_tracker_handle_add_group_name(
-                                                       tracker_handle,
-                                                       (const char *) content);
-                                       break;
-                               case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
-                                       status = lttng_process_attr_virtual_group_id_tracker_handle_add_group_name(
-                                                       tracker_handle,
-                                                       (const char *) content);
-                                       break;
-                               default:
-                                       free(content);
-                                       ret = LTTNG_ERR_INVALID;
-                                       goto end;
-                               }
-                               free(content);
-                       }
-                       switch (status) {
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
-                               continue;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
-                               ret = LTTNG_ERR_INVALID;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
-                               ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
-                               ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
-                               break;
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
-                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
-                       default:
-                               ret = LTTNG_ERR_UNK;
-                               goto end;
-                       }
-               }
-               node = id_target_node;
-       }
-
-end:
-       lttng_process_attr_tracker_handle_destroy(tracker_handle);
-       return ret;
-}
-
-static
-int process_domain_node(xmlNodePtr domain_node, const char *session_name)
-{
-       int ret;
-       struct lttng_domain domain = { 0 };
-       struct lttng_handle *handle = NULL;
-       struct lttng_channel *channel = NULL;
-       xmlNodePtr channels_node = NULL;
-       xmlNodePtr trackers_node = NULL;
-       xmlNodePtr pid_tracker_node = NULL;
-       xmlNodePtr vpid_tracker_node = NULL;
-       xmlNodePtr uid_tracker_node = NULL;
-       xmlNodePtr vuid_tracker_node = NULL;
-       xmlNodePtr gid_tracker_node = NULL;
-       xmlNodePtr vgid_tracker_node = NULL;
-       xmlNodePtr node;
-
-       LTTNG_ASSERT(session_name);
-
-       ret = init_domain(domain_node, &domain);
-       if (ret) {
-               goto end;
-       }
-
-       handle = lttng_create_handle(session_name, &domain);
-       if (!handle) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto end;
-       }
-
-       /* get the channels node */
-       for (node = xmlFirstElementChild(domain_node); node;
-               node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name,
-                       config_element_channels)) {
-                       channels_node = node;
-                       break;
-               }
-       }
-
-       if (!channels_node) {
-               goto end;
-       }
-
-       /* create all channels */
-       for (node = xmlFirstElementChild(channels_node); node;
-               node = xmlNextElementSibling(node)) {
-               const enum lttng_domain_type original_domain = domain.type;
-               xmlNodePtr contexts_node = NULL;
-               xmlNodePtr events_node = NULL;
-               xmlNodePtr channel_attr_node;
-
-               /*
-                * Channels of the "agent" types cannot be created directly.
-                * They are meant to be created implicitly through the
-                * activation of events in their domain. However, a user
-                * can override the default channel configuration attributes
-                * by creating the underlying UST channel _before_ enabling
-                * an agent domain event.
-                *
-                * Hence, the channel's type is substituted before the creation
-                * and restored by the time the events are created.
-                */
-               switch (domain.type) {
-               case LTTNG_DOMAIN_JUL:
-               case LTTNG_DOMAIN_LOG4J:
-               case LTTNG_DOMAIN_PYTHON:
-                       domain.type = LTTNG_DOMAIN_UST;
-               default:
-                       break;
-               }
-
-               channel = lttng_channel_create(&domain);
-               if (!channel) {
-                       ret = -1;
-                       goto end;
-               }
-
-               for (channel_attr_node = xmlFirstElementChild(node);
-                       channel_attr_node; channel_attr_node =
-                       xmlNextElementSibling(channel_attr_node)) {
-                       ret = process_channel_attr_node(channel_attr_node,
-                               channel, &contexts_node, &events_node);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-
-               ret = lttng_enable_channel(handle, channel);
-               if (ret < 0) {
-                       goto end;
-               }
-
-               /* Restore the original channel domain. */
-               domain.type = original_domain;
-
-               ret = process_events_node(events_node, handle, channel->name);
-               if (ret) {
-                       goto end;
-               }
-
-               ret = process_contexts_node(contexts_node, handle,
-                       channel->name);
-               if (ret) {
-                       goto end;
-               }
-
-               lttng_channel_destroy(channel);
-       }
-       channel = NULL;
-
-       /* get the trackers node */
-       for (node = xmlFirstElementChild(domain_node); node;
-                       node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_trackers) ||
-                               !strcmp((const char *) node->name,
-                                               config_element_trackers_legacy)) {
-                       if (trackers_node) {
-                               ERR("Only one instance of `%s` or `%s` is allowed in a session configuration",
-                                               config_element_process_attr_trackers,
-                                               config_element_trackers_legacy);
-                               ret = -1;
-                               goto end;
-                       }
-                       trackers_node = node;
-                       break;
-               }
-       }
-
-       if (!trackers_node) {
-               goto end;
-       }
-
-       for (node = xmlFirstElementChild(trackers_node); node;
-                       node = xmlNextElementSibling(node)) {
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_pid)) {
-                       pid_tracker_node = node;
-                       ret = process_id_tracker_node(pid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_PROCESS_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_vpid)) {
-                       vpid_tracker_node = node;
-                       ret = process_id_tracker_node(vpid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_uid)) {
-                       uid_tracker_node = node;
-                       ret = process_id_tracker_node(uid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_USER_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_vuid)) {
-                       vuid_tracker_node = node;
-                       ret = process_id_tracker_node(vuid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_gid)) {
-                       gid_tracker_node = node;
-                       ret = process_id_tracker_node(gid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_GROUP_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_process_attr_tracker_vgid)) {
-                       vgid_tracker_node = node;
-                       ret = process_id_tracker_node(vgid_tracker_node, handle,
-                                       LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-               if (!strcmp((const char *) node->name,
-                                   config_element_pid_tracker_legacy)) {
-                       ret = process_legacy_pid_tracker_node(node, handle);
-                       if (ret) {
-                               goto end;
-                       }
-               }
-       }
-
-end:
-       lttng_channel_destroy(channel);
-       lttng_destroy_handle(handle);
-       return ret;
-}
-
-static
-int add_periodic_rotation(const char *name, uint64_t time_us)
-{
-       int ret;
-       enum lttng_rotation_status status;
-       struct lttng_rotation_schedule *periodic =
-                       lttng_rotation_schedule_periodic_create();
-
-       if (!periodic) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto error;
-       }
-
-       status = lttng_rotation_schedule_periodic_set_period(periodic,
-                       time_us);
-       if (status != LTTNG_ROTATION_STATUS_OK) {
-               ret = -LTTNG_ERR_INVALID;
-               goto error;
-       }
-
-       status = lttng_session_add_rotation_schedule(name, periodic);
-       switch (status) {
-       case LTTNG_ROTATION_STATUS_OK:
-               ret = 0;
-               break;
-       case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
-       case LTTNG_ROTATION_STATUS_INVALID:
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               break;
-       default:
-               ret = -LTTNG_ERR_UNK;
-               break;
-       }
-error:
-       lttng_rotation_schedule_destroy(periodic);
-       return ret;
-}
-
-static
-int add_size_rotation(const char *name, uint64_t size_bytes)
-{
-       int ret;
-       enum lttng_rotation_status status;
-       struct lttng_rotation_schedule *size =
-                       lttng_rotation_schedule_size_threshold_create();
-
-       if (!size) {
-               ret = -LTTNG_ERR_NOMEM;
-               goto error;
-       }
-
-       status = lttng_rotation_schedule_size_threshold_set_threshold(size,
-                       size_bytes);
-       if (status != LTTNG_ROTATION_STATUS_OK) {
-               ret = -LTTNG_ERR_INVALID;
-               goto error;
-       }
-
-       status = lttng_session_add_rotation_schedule(name, size);
-       switch (status) {
-       case LTTNG_ROTATION_STATUS_OK:
-               ret = 0;
-               break;
-       case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
-       case LTTNG_ROTATION_STATUS_INVALID:
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               break;
-       default:
-               ret = -LTTNG_ERR_UNK;
-               break;
-       }
-error:
-       lttng_rotation_schedule_destroy(size);
-       return ret;
-}
-
-static
-int process_session_rotation_schedules_node(
-               xmlNodePtr schedules_node,
-               uint64_t *rotation_timer_interval,
-               uint64_t *rotation_size)
-{
-       int ret = 0;
-       xmlNodePtr child;
-
-       for (child = xmlFirstElementChild(schedules_node);
-                       child;
-                       child = xmlNextElementSibling(child)) {
-               if (!strcmp((const char *) child->name,
-                               config_element_rotation_schedule_periodic)) {
-                       xmlChar *content;
-                       xmlNodePtr time_us_node;
-
-                       /* periodic rotation schedule */
-                       time_us_node = xmlFirstElementChild(child);
-                       if (!time_us_node ||
-                                       strcmp((const char *) time_us_node->name,
-                                               config_element_rotation_schedule_periodic_time_us)) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       /* time_us child */
-                       content = xmlNodeGetContent(time_us_node);
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-                       ret = parse_uint(content, rotation_timer_interval);
-                       free(content);
-                       if (ret) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-               } else if (!strcmp((const char *) child->name,
-                               config_element_rotation_schedule_size_threshold)) {
-                       xmlChar *content;
-                       xmlNodePtr bytes_node;
-
-                       /* size_threshold rotation schedule */
-                       bytes_node = xmlFirstElementChild(child);
-                       if (!bytes_node ||
-                                       strcmp((const char *) bytes_node->name,
-                                               config_element_rotation_schedule_size_threshold_bytes)) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-
-                       /* bytes child */
-                       content = xmlNodeGetContent(bytes_node);
-                       if (!content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-                       ret = parse_uint(content, rotation_size);
-                       free(content);
-                       if (ret) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto end;
-                       }
-               }
-       }
-
-end:
-       return ret;
-}
-
-static
-int process_session_node(xmlNodePtr session_node, const char *session_name,
-               int overwrite,
-               const struct config_load_session_override_attr *overrides)
-{
-       int ret, started = -1, snapshot_mode = -1;
-       uint64_t live_timer_interval = UINT64_MAX,
-                        rotation_timer_interval = 0,
-                        rotation_size = 0;
-       xmlChar *name = NULL;
-       xmlChar *shm_path = NULL;
-       xmlNodePtr domains_node = NULL;
-       xmlNodePtr output_node = NULL;
-       xmlNodePtr node;
-       xmlNodePtr attributes_child;
-       struct lttng_domain *kernel_domain = NULL;
-       struct lttng_domain *ust_domain = NULL;
-       struct lttng_domain *jul_domain = NULL;
-       struct lttng_domain *log4j_domain = NULL;
-       struct lttng_domain *python_domain = NULL;
-
-       for (node = xmlFirstElementChild(session_node); node;
-               node = xmlNextElementSibling(node)) {
-               if (!name && !strcmp((const char *) node->name,
-                       config_element_name)) {
-                       /* name */
-                       xmlChar *node_content = xmlNodeGetContent(node);
-                       if (!node_content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto error;
-                       }
-
-                       name = node_content;
-               } else if (!domains_node && !strcmp((const char *) node->name,
-                       config_element_domains)) {
-                       /* domains */
-                       domains_node = node;
-               } else if (started == -1 && !strcmp((const char *) node->name,
-                       config_element_started)) {
-                       /* started */
-                       xmlChar *node_content = xmlNodeGetContent(node);
-                       if (!node_content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto error;
-                       }
-
-                       ret = parse_bool(node_content, &started);
-                       free(node_content);
-                       if (ret) {
-                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                               goto error;
-                       }
-               } else if (!output_node && !strcmp((const char *) node->name,
-                       config_element_output)) {
-                       /* output */
-                       output_node = node;
-               } else if (!shm_path && !strcmp((const char *) node->name,
-                       config_element_shared_memory_path)) {
-                       /* shared memory path */
-                       xmlChar *node_content = xmlNodeGetContent(node);
-                       if (!node_content) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto error;
-                       }
-
-                       shm_path = node_content;
-               } else {
-                       /*
-                        * attributes, snapshot_mode, live_timer_interval, rotation_size,
-                        * rotation_timer_interval.
-                        */
-                       for (attributes_child = xmlFirstElementChild(node); attributes_child;
-                                       attributes_child = xmlNextElementSibling(attributes_child)) {
-                               if (!strcmp((const char *) attributes_child->name,
-                                                       config_element_snapshot_mode)) {
-                                       /* snapshot_mode */
-                                       xmlChar *snapshot_mode_content =
-                                               xmlNodeGetContent(attributes_child);
-                                       if (!snapshot_mode_content) {
-                                               ret = -LTTNG_ERR_NOMEM;
-                                               goto error;
-                                       }
-
-                                       ret = parse_bool(snapshot_mode_content, &snapshot_mode);
-                                       free(snapshot_mode_content);
-                                       if (ret) {
-                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                               goto error;
-                                       }
-                               } else if (!strcmp((const char *) attributes_child->name,
-                                                       config_element_live_timer_interval)) {
-                                       /* live_timer_interval */
-                                       xmlChar *timer_interval_content =
-                                               xmlNodeGetContent(attributes_child);
-                                       if (!timer_interval_content) {
-                                               ret = -LTTNG_ERR_NOMEM;
-                                               goto error;
-                                       }
-
-                                       ret = parse_uint(timer_interval_content, &live_timer_interval);
-                                       free(timer_interval_content);
-                                       if (ret) {
-                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                               goto error;
-                                       }
-                               } else if (!strcmp((const char *) attributes_child->name,
-                                                       config_element_rotation_schedules)) {
-                                       ret = process_session_rotation_schedules_node(
-                                                       attributes_child,
-                                                       &rotation_timer_interval,
-                                                       &rotation_size);
-                                       if (ret) {
-                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-                                               goto error;
-                                       }
-
-                               }
-                       }
-               }
-       }
-
-       if (!name) {
-               /* Mandatory attribute, as defined in the session XSD */
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto error;
-       }
-
-       if (session_name && strcmp((char *) name, session_name)) {
-               /* This is not the session we are looking for */
-               ret = -LTTNG_ERR_NO_SESSION;
-               goto error;
-       }
-
-       /* Init domains to create the session handles */
-       for (node = xmlFirstElementChild(domains_node); node;
-               node = xmlNextElementSibling(node)) {
-               struct lttng_domain *domain;
-
-               domain = zmalloc(sizeof(*domain));
-               if (!domain) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto error;
-               }
-
-               ret = init_domain(node, domain);
-               if (ret) {
-                       goto domain_init_error;
-               }
-
-               switch (domain->type) {
-               case LTTNG_DOMAIN_KERNEL:
-                       if (kernel_domain) {
-                               /* Same domain seen twice, invalid! */
-                               goto domain_init_error;
-                       }
-                       kernel_domain = domain;
-                       break;
-               case LTTNG_DOMAIN_UST:
-                       if (ust_domain) {
-                               /* Same domain seen twice, invalid! */
-                               goto domain_init_error;
-                       }
-                       ust_domain = domain;
-                       break;
-               case LTTNG_DOMAIN_JUL:
-                       if (jul_domain) {
-                               /* Same domain seen twice, invalid! */
-                               goto domain_init_error;
-                       }
-                       jul_domain = domain;
-                       break;
-               case LTTNG_DOMAIN_LOG4J:
-                       if (log4j_domain) {
-                               /* Same domain seen twice, invalid! */
-                               goto domain_init_error;
-                       }
-                       log4j_domain = domain;
-                       break;
-               case LTTNG_DOMAIN_PYTHON:
-                       if (python_domain) {
-                               /* Same domain seen twice, invalid! */
-                               goto domain_init_error;
-                       }
-                       python_domain = domain;
-                       break;
-               default:
-                       WARN("Invalid domain type");
-                       goto domain_init_error;
-               }
-               continue;
-domain_init_error:
-               free(domain);
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto error;
-       }
-
-       /* Apply overrides */
-       if (overrides) {
-               if (overrides->session_name) {
-                       xmlChar *name_override = xmlStrdup(BAD_CAST(overrides->session_name));
-                       if (!name_override) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto error;
-                       }
-
-                       /* Overrides the session name to the provided name */
-                       xmlFree(name);
-                       name = name_override;
-               }
-       }
-
-       if (overwrite) {
-               /* Destroy session if it exists */
-               ret = lttng_destroy_session((const char *) name);
-               if (ret && ret != -LTTNG_ERR_SESS_NOT_FOUND) {
-                       ERR("Failed to destroy existing session.");
-                       goto error;
-               }
-       }
-
-       /* Create session type depending on output type */
-       if (snapshot_mode && snapshot_mode != -1) {
-               ret = create_snapshot_session((const char *) name, output_node,
-                               overrides);
-       } else if (live_timer_interval &&
-               live_timer_interval != UINT64_MAX) {
-               ret = create_session((const char *) name,
-                               output_node, live_timer_interval, overrides);
-       } else {
-               /* regular session */
-               ret = create_session((const char *) name,
-                               output_node, UINT64_MAX, overrides);
-       }
-       if (ret) {
-               goto error;
-       }
-
-       if (shm_path) {
-               ret = lttng_set_session_shm_path((const char *) name,
-                               (const char *) shm_path);
-               if (ret) {
-                       goto error;
-               }
-       }
-
-       for (node = xmlFirstElementChild(domains_node); node;
-               node = xmlNextElementSibling(node)) {
-               ret = process_domain_node(node, (const char *) name);
-               if (ret) {
-                       goto end;
-               }
-       }
-
-       if (rotation_timer_interval) {
-               ret = add_periodic_rotation((const char *) name,
-                               rotation_timer_interval);
-               if (ret < 0) {
-                       goto error;
-               }
-       }
-       if (rotation_size) {
-               ret = add_size_rotation((const char *) name,
-                               rotation_size);
-               if (ret < 0) {
-                       goto error;
-               }
-       }
-
-       if (started) {
-               ret = lttng_start_tracing((const char *) name);
-               if (ret) {
-                       goto end;
-               }
-       }
-
-end:
-       if (ret < 0) {
-               ERR("Failed to load session %s: %s", (const char *) name,
-                       lttng_strerror(ret));
-               lttng_destroy_session((const char *) name);
-       }
-
-error:
-       free(kernel_domain);
-       free(ust_domain);
-       free(jul_domain);
-       free(log4j_domain);
-       free(python_domain);
-       xmlFree(name);
-       xmlFree(shm_path);
-       return ret;
-}
-
-/*
- * Return 1 if the given path is readable by the current UID or 0 if not.
- * Return -1 if the path is EPERM.
- */
-static int validate_file_read_creds(const char *path)
-{
-       int ret;
-
-       LTTNG_ASSERT(path);
-
-       /* Can we read the file. */
-       ret = access(path, R_OK);
-       if (!ret) {
-               goto valid;
-       }
-       if (errno == EACCES) {
-               return -1;
-       } else {
-               /* Invalid. */
-               return 0;
-       }
-valid:
-       return 1;
-}
-
-static
-int load_session_from_file(const char *path, const char *session_name,
-       struct session_config_validation_ctx *validation_ctx, int overwrite,
-       const struct config_load_session_override_attr *overrides)
-{
-       int ret, session_found = !session_name;
-       xmlDocPtr doc = NULL;
-       xmlNodePtr sessions_node;
-       xmlNodePtr session_node;
-
-       LTTNG_ASSERT(path);
-       LTTNG_ASSERT(validation_ctx);
-
-       ret = validate_file_read_creds(path);
-       if (ret != 1) {
-               if (ret == -1) {
-                       ret = -LTTNG_ERR_EPERM;
-               } else {
-                       ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
-               }
-               goto end;
-       }
-
-       doc = xmlParseFile(path);
-       if (!doc) {
-               ret = -LTTNG_ERR_LOAD_IO_FAIL;
-               goto end;
-       }
-
-       ret = xmlSchemaValidateDoc(validation_ctx->schema_validation_ctx, doc);
-       if (ret) {
-               ERR("Session configuration file validation failed");
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       sessions_node = xmlDocGetRootElement(doc);
-       if (!sessions_node) {
-               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
-               goto end;
-       }
-
-       for (session_node = xmlFirstElementChild(sessions_node);
-               session_node; session_node =
-                       xmlNextElementSibling(session_node)) {
-               ret = process_session_node(session_node,
-                       session_name, overwrite, overrides);
-               if (!session_name && ret) {
-                       /* Loading error occurred. */
-                       goto end;
-               } else if (session_name) {
-                       if (ret == 0) {
-                               /* Target session found and loaded */
-                               session_found = 1;
-                               break;
-                       } else if (ret == -LTTNG_ERR_NO_SESSION) {
-                               /*
-                                * Ignore this error, we are looking for a
-                                * specific session.
-                                */
-                               ret = 0;
-                       } else {
-                               /* Loading error occurred. */
-                               goto end;
-                       }
-               }
-       }
-end:
-       xmlFreeDoc(doc);
-       if (!ret) {
-               ret = session_found ? 0 : -LTTNG_ERR_LOAD_SESSION_NOENT;
-       }
-       return ret;
-}
-
-static
-int load_session_from_path(const char *path, const char *session_name,
-       struct session_config_validation_ctx *validation_ctx, int overwrite,
-       const struct config_load_session_override_attr *overrides)
-{
-       int ret, session_found = !session_name;
-       DIR *directory = NULL;
-       struct lttng_dynamic_buffer file_path;
-       size_t path_len;
-
-       LTTNG_ASSERT(path);
-       LTTNG_ASSERT(validation_ctx);
-       path_len = strlen(path);
-       lttng_dynamic_buffer_init(&file_path);
-       if (path_len >= LTTNG_PATH_MAX) {
-               ERR("Session configuration load path \"%s\" length (%zu) exceeds the maximal length allowed (%d)",
-                               path, path_len, LTTNG_PATH_MAX);
-               ret = -LTTNG_ERR_INVALID;
-               goto end;
-       }
-
-       directory = opendir(path);
-       if (!directory) {
-               switch (errno) {
-               case ENOTDIR:
-                       /* Try the file loading. */
-                       break;
-               case ENOENT:
-                       ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
-                       goto end;
-               default:
-                       ret = -LTTNG_ERR_LOAD_IO_FAIL;
-                       goto end;
-               }
-       }
-       if (directory) {
-               size_t file_path_root_len;
-
-               ret = lttng_dynamic_buffer_set_capacity(&file_path,
-                               LTTNG_PATH_MAX);
-               if (ret) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               ret = lttng_dynamic_buffer_append(&file_path, path, path_len);
-               if (ret) {
-                       ret = -LTTNG_ERR_NOMEM;
-                       goto end;
-               }
-
-               if (file_path.data[file_path.size - 1] != '/') {
-                       ret = lttng_dynamic_buffer_append(&file_path, "/", 1);
-                       if (ret) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-               }
-               file_path_root_len = file_path.size;
-
-               /* Search for *.lttng files */
-               for (;;) {
-                       size_t file_name_len;
-                       struct dirent *result;
-
-                       /*
-                        * When the end of the directory stream is reached, NULL
-                        * is returned and errno is kept unchanged. When an
-                        * error occurs, NULL is returned and errno is set
-                        * accordingly. To distinguish between the two, set
-                        * errno to zero before calling readdir().
-                        *
-                        * On success, readdir() returns a pointer to a dirent
-                        * structure. This structure may be statically
-                        * allocated, do not attempt to free(3) it.
-                        */
-                       errno = 0;
-                       result = readdir(directory);
-
-                       /* Reached end of dir stream or error out. */
-                       if (!result) {
-                               if (errno) {
-                                       PERROR("Failed to enumerate the contents of path \"%s\" while loading session, readdir returned", path);
-                                       ret = -LTTNG_ERR_LOAD_IO_FAIL;
-                                       goto end;
-                               }
-                               break;
-                       }
-
-                       file_name_len = strlen(result->d_name);
-
-                       if (file_name_len <=
-                               sizeof(DEFAULT_SESSION_CONFIG_FILE_EXTENSION)) {
-                               continue;
-                       }
-
-                       if (file_path.size + file_name_len >= LTTNG_PATH_MAX) {
-                               WARN("Ignoring file \"%s\" since the path's length (%zu) would exceed the maximal permitted size (%d)",
-                                               result->d_name,
-                                               /* +1 to account for NULL terminator. */
-                                               file_path.size + file_name_len + 1,
-                                               LTTNG_PATH_MAX);
-                               continue;
-                       }
-
-                       /* Does the file end with .lttng? */
-                       if (strcmp(DEFAULT_SESSION_CONFIG_FILE_EXTENSION,
-                                       result->d_name + file_name_len - sizeof(
-                                       DEFAULT_SESSION_CONFIG_FILE_EXTENSION) + 1)) {
-                               continue;
-                       }
-
-                       ret = lttng_dynamic_buffer_append(&file_path, result->d_name,
-                                       file_name_len + 1);
-                       if (ret) {
-                               ret = -LTTNG_ERR_NOMEM;
-                               goto end;
-                       }
-
-                       ret = load_session_from_file(file_path.data, session_name,
-                               validation_ctx, overwrite, overrides);
-                       if (session_name &&
-                                       (!ret || ret != -LTTNG_ERR_LOAD_SESSION_NOENT)) {
-                               session_found = 1;
-                               break;
-                       }
-                       if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
-                               goto end;
-                       }
-                       /*
-                        * Reset the buffer's size to the location of the
-                        * path's trailing '/'.
-                        */
-                       ret = lttng_dynamic_buffer_set_size(&file_path,
-                                       file_path_root_len);
-                       if (ret) {
-                               ret = -LTTNG_ERR_UNK;
-                               goto end;
-                       }
-               }
-       } else {
-               ret = load_session_from_file(path, session_name,
-                       validation_ctx, overwrite, overrides);
-               if (ret) {
-                       goto end;
-               }
-               session_found = 1;
-       }
-
-       ret = 0;
-end:
-       if (directory) {
-               if (closedir(directory)) {
-                       PERROR("closedir");
-               }
-       }
-       if (!ret && !session_found) {
-               ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
-       }
-       lttng_dynamic_buffer_reset(&file_path);
-       return ret;
-}
-
-/*
- * Validate that the given path's credentials and the current process have the
- * same UID. If so, return 1 else return 0 if it does NOT match.
- */
-static int validate_path_creds(const char *path)
-{
-       int ret, uid = getuid();
-       struct stat buf;
-
-       LTTNG_ASSERT(path);
-
-       if (uid == 0) {
-               goto valid;
-       }
-
-       ret = stat(path, &buf);
-       if (ret < 0) {
-               if (errno != ENOENT) {
-                       PERROR("stat");
-               }
-               goto valid;
-       }
-
-       if (buf.st_uid != uid) {
-               goto invalid;
-       }
-
-valid:
-       return 1;
-invalid:
-       return 0;
-}
-
-int config_load_session(const char *path, const char *session_name,
-               int overwrite, unsigned int autoload,
-               const struct config_load_session_override_attr *overrides)
-{
-       int ret;
-       bool session_loaded = false;
-       const char *path_ptr = NULL;
-       struct session_config_validation_ctx validation_ctx = { 0 };
-
-       ret = init_session_config_validation_ctx(&validation_ctx);
-       if (ret) {
-               goto end;
-       }
-
-       if (!path) {
-               const char *home_path;
-               const char *sys_path;
-
-               /* Try home path */
-               home_path = utils_get_home_dir();
-               if (home_path) {
-                       char path_buf[PATH_MAX];
-
-                       /*
-                        * Try user session configuration path. Ignore error here so we can
-                        * continue loading the system wide sessions.
-                        */
-                       if (autoload) {
-                               ret = snprintf(path_buf, sizeof(path_buf),
-                                               DEFAULT_SESSION_HOME_CONFIGPATH
-                                               "/" DEFAULT_SESSION_CONFIG_AUTOLOAD,
-                                               home_path);
-                               if (ret < 0) {
-                                       PERROR("snprintf session autoload home config path");
-                                       ret = -LTTNG_ERR_INVALID;
-                                       goto end;
-                               }
-
-                               /*
-                                * Credentials are only validated for the autoload in order to
-                                * avoid any user session daemon to try to load kernel sessions
-                                * automatically and failing all the times.
-                                */
-                               ret = validate_path_creds(path_buf);
-                               if (ret) {
-                                       path_ptr = path_buf;
-                               }
-                       } else {
-                               ret = snprintf(path_buf, sizeof(path_buf),
-                                               DEFAULT_SESSION_HOME_CONFIGPATH,
-                                               home_path);
-                               if (ret < 0) {
-                                       PERROR("snprintf session home config path");
-                                       ret = -LTTNG_ERR_INVALID;
-                                       goto end;
-                               }
-                               path_ptr = path_buf;
-                       }
-                       if (path_ptr) {
-                               ret = load_session_from_path(path_ptr, session_name,
-                                               &validation_ctx, overwrite, overrides);
-                               if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
-                                       goto end;
-                               }
-                               /*
-                                * Continue even if the session was found since we have to try
-                                * the system wide sessions.
-                                */
-                               session_loaded = true;
-                       }
-               }
-
-               /* Reset path pointer for the system wide dir. */
-               path_ptr = NULL;
-
-               /* Try system wide configuration directory. */
-               if (autoload) {
-                       sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH "/"
-                               DEFAULT_SESSION_CONFIG_AUTOLOAD;
-                       ret = validate_path_creds(sys_path);
-                       if (ret) {
-                               path_ptr = sys_path;
-                       }
-               } else {
-                       sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH;
-                       path_ptr = sys_path;
-               }
-
-               if (path_ptr) {
-                       ret = load_session_from_path(path_ptr, session_name,
-                                       &validation_ctx, overwrite, overrides);
-                       if (!ret) {
-                               session_loaded = true;
-                       }
-               } else {
-                       ret = 0;
-               }
-       } else {
-               ret = access(path, F_OK);
-               if (ret < 0) {
-                       PERROR("access");
-                       switch (errno) {
-                       case ENOENT:
-                               ret = -LTTNG_ERR_INVALID;
-                               WARN("Session configuration path does not exist.");
-                               break;
-                       case EACCES:
-                               ret = -LTTNG_ERR_EPERM;
-                               break;
-                       default:
-                               ret = -LTTNG_ERR_UNK;
-                               break;
-                       }
-                       goto end;
-               }
-
-               ret = load_session_from_path(path, session_name,
-                       &validation_ctx, overwrite, overrides);
-       }
-end:
-       fini_session_config_validation_ctx(&validation_ctx);
-       if (ret == -LTTNG_ERR_LOAD_SESSION_NOENT && !session_name && !path) {
-               /*
-                * Don't report an error if no sessions are found when called
-                * without a session_name or a search path.
-                */
-               ret = 0;
-       }
-
-       if (session_loaded && ret == -LTTNG_ERR_LOAD_SESSION_NOENT) {
-               /* A matching session was found in one of the search paths. */
-               ret = 0;
-       }
-       return ret;
-}
-
-static
-void __attribute__((destructor)) session_config_exit(void)
-{
-       xmlCleanupParser();
-}
diff --git a/src/common/config/session-config.cpp b/src/common/config/session-config.cpp
new file mode 100644 (file)
index 0000000..4d57d58
--- /dev/null
@@ -0,0 +1,4152 @@
+/*
+ * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#include "lttng/tracker.h"
+#define _LGPL_SOURCE
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdbool.h>
+
+#include <common/defaults.h>
+#include <common/error.h>
+#include <common/macros.h>
+#include <common/utils.h>
+#include <common/dynamic-buffer.h>
+#include <common/compat/getenv.h>
+#include <lttng/lttng-error.h>
+#include <libxml/parser.h>
+#include <libxml/valid.h>
+#include <libxml/xmlschemas.h>
+#include <libxml/tree.h>
+#include <lttng/lttng.h>
+#include <lttng/snapshot.h>
+#include <lttng/rotation.h>
+#include <lttng/userspace-probe.h>
+
+#include "session-config.h"
+#include "config-internal.h"
+
+#define CONFIG_USERSPACE_PROBE_LOOKUP_METHOD_NAME_MAX_LEN 7
+
+struct handler_filter_args {
+       const char* section;
+       config_entry_handler_cb handler;
+       void *user_data;
+};
+
+struct session_config_validation_ctx {
+       xmlSchemaParserCtxtPtr parser_ctx;
+       xmlSchemaPtr schema;
+       xmlSchemaValidCtxtPtr schema_validation_ctx;
+};
+
+const char * const config_element_all = "all";
+LTTNG_EXPORT const char *config_str_yes = "yes";
+LTTNG_EXPORT const char *config_str_true = "true";
+LTTNG_EXPORT const char *config_str_on = "on";
+LTTNG_EXPORT const char *config_str_no = "no";
+LTTNG_EXPORT const char *config_str_false = "false";
+LTTNG_EXPORT const char *config_str_off = "off";
+LTTNG_EXPORT const char *config_xml_encoding = "UTF-8";
+LTTNG_EXPORT size_t config_xml_encoding_bytes_per_char = 2;    /* Size of the encoding's largest character */
+LTTNG_EXPORT const char *config_xml_indent_string = "\t";
+LTTNG_EXPORT const char *config_xml_true = "true";
+LTTNG_EXPORT const char *config_xml_false = "false";
+
+const char * const config_element_channel = "channel";
+const char * const config_element_channels = "channels";
+const char * const config_element_domain = "domain";
+const char * const config_element_domains = "domains";
+const char * const config_element_event = "event";
+const char * const config_element_events = "events";
+const char * const config_element_context = "context";
+const char * const config_element_contexts = "contexts";
+const char * const config_element_attributes = "attributes";
+const char * const config_element_exclusion = "exclusion";
+const char * const config_element_exclusions = "exclusions";
+const char * const config_element_function_attributes = "function_attributes";
+const char * const config_element_probe_attributes = "probe_attributes";
+const char * const config_element_symbol_name = "symbol_name";
+const char * const config_element_address = "address";
+const char * const config_element_offset = "offset";
+
+const char * const config_element_userspace_probe_lookup = "lookup_method";
+const char * const config_element_userspace_probe_lookup_function_default = "DEFAULT";
+const char * const config_element_userspace_probe_lookup_function_elf = "ELF";
+const char * const config_element_userspace_probe_lookup_tracepoint_sdt = "SDT";
+const char * const config_element_userspace_probe_location_binary_path = "binary_path";
+const char * const config_element_userspace_probe_function_attributes = "userspace_probe_function_attributes";
+const char * const config_element_userspace_probe_function_location_function_name = "function_name";
+const char * const config_element_userspace_probe_tracepoint_attributes = "userspace_probe_tracepoint_attributes";
+const char * const config_element_userspace_probe_tracepoint_location_provider_name = "provider_name";
+const char * const config_element_userspace_probe_tracepoint_location_probe_name = "probe_name";
+
+const char * const config_element_name = "name";
+const char * const config_element_enabled = "enabled";
+const char * const config_element_overwrite_mode = "overwrite_mode";
+const char * const config_element_subbuf_size = "subbuffer_size";
+const char * const config_element_num_subbuf = "subbuffer_count";
+const char * const config_element_switch_timer_interval = "switch_timer_interval";
+const char * const config_element_read_timer_interval = "read_timer_interval";
+const char * const config_element_monitor_timer_interval = "monitor_timer_interval";
+const char * const config_element_blocking_timeout = "blocking_timeout";
+const char * const config_element_output = "output";
+const char * const config_element_output_type = "output_type";
+const char * const config_element_tracefile_size = "tracefile_size";
+const char * const config_element_tracefile_count = "tracefile_count";
+const char * const config_element_live_timer_interval = "live_timer_interval";
+const char * const config_element_discarded_events = "discarded_events";
+const char * const config_element_lost_packets = "lost_packets";
+const char * const config_element_type = "type";
+const char * const config_element_buffer_type = "buffer_type";
+const char * const config_element_session = "session";
+const char * const config_element_sessions = "sessions";
+const char * const config_element_context_perf = "perf";
+const char * const config_element_context_app = "app";
+const char * const config_element_context_app_provider_name = "provider_name";
+const char * const config_element_context_app_ctx_name = "ctx_name";
+const char * const config_element_config = "config";
+const char * const config_element_started = "started";
+const char * const config_element_snapshot_mode = "snapshot_mode";
+const char * const config_element_loglevel = "loglevel";
+const char * const config_element_loglevel_type = "loglevel_type";
+const char * const config_element_filter = "filter";
+const char * const config_element_filter_expression = "filter_expression";
+const char * const config_element_snapshot_outputs = "snapshot_outputs";
+const char * const config_element_consumer_output = "consumer_output";
+const char * const config_element_destination = "destination";
+const char * const config_element_path = "path";
+const char * const config_element_net_output = "net_output";
+const char * const config_element_control_uri = "control_uri";
+const char * const config_element_data_uri = "data_uri";
+const char * const config_element_max_size = "max_size";
+const char * const config_element_pid = "pid";
+const char * const config_element_pids = "pids";
+const char * const config_element_shared_memory_path = "shared_memory_path";
+
+const char * const config_element_process_attr_id = "id";
+const char * const config_element_process_attr_tracker_pid = "pid_process_attr_tracker";
+const char * const config_element_process_attr_tracker_vpid = "vpid_process_attr_tracker";
+const char * const config_element_process_attr_tracker_uid = "uid_process_attr_tracker";
+const char * const config_element_process_attr_tracker_vuid = "vuid_process_attr_tracker";
+const char * const config_element_process_attr_tracker_gid = "gid_process_attr_tracker";
+const char * const config_element_process_attr_tracker_vgid = "vgid_process_attr_tracker";
+const char * const config_element_process_attr_trackers = "process_attr_trackers";
+const char * const config_element_process_attr_values = "process_attr_values";
+const char * const config_element_process_attr_value_type = "process_attr_value_type";
+const char * const config_element_process_attr_pid_value = "pid";
+const char * const config_element_process_attr_vpid_value = "vpid";
+const char * const config_element_process_attr_uid_value = "uid";
+const char * const config_element_process_attr_vuid_value = "vuid";
+const char * const config_element_process_attr_gid_value = "gid";
+const char * const config_element_process_attr_vgid_value = "vgid";
+const char * const config_element_process_attr_tracker_type = "process_attr_tracker_type";
+
+/* Used for support of legacy tracker serialization (< 2.12). */
+const char * const config_element_trackers_legacy = "trackers";
+const char * const config_element_pid_tracker_legacy = "pid_tracker";
+const char * const config_element_tracker_targets_legacy = "targets";
+const char * const config_element_tracker_pid_legacy = "pid";
+
+const char * const config_element_rotation_schedules = "rotation_schedules";
+const char * const config_element_rotation_schedule_periodic = "periodic";
+const char * const config_element_rotation_schedule_periodic_time_us = "time_us";
+const char * const config_element_rotation_schedule_size_threshold = "size_threshold";
+const char * const config_element_rotation_schedule_size_threshold_bytes = "bytes";
+
+const char * const config_domain_type_kernel = "KERNEL";
+const char * const config_domain_type_ust = "UST";
+const char * const config_domain_type_jul = "JUL";
+const char * const config_domain_type_log4j = "LOG4J";
+const char * const config_domain_type_python = "PYTHON";
+
+const char * const config_buffer_type_per_pid = "PER_PID";
+const char * const config_buffer_type_per_uid = "PER_UID";
+const char * const config_buffer_type_global = "GLOBAL";
+
+const char * const config_overwrite_mode_discard = "DISCARD";
+const char * const config_overwrite_mode_overwrite = "OVERWRITE";
+
+const char * const config_output_type_splice = "SPLICE";
+const char * const config_output_type_mmap = "MMAP";
+
+const char * const config_loglevel_type_all = "ALL";
+const char * const config_loglevel_type_range = "RANGE";
+const char * const config_loglevel_type_single = "SINGLE";
+
+const char * const config_event_type_all = "ALL";
+const char * const config_event_type_tracepoint = "TRACEPOINT";
+const char * const config_event_type_probe = "PROBE";
+const char * const config_event_type_userspace_probe = "USERSPACE_PROBE";
+const char * const config_event_type_function = "FUNCTION";
+const char * const config_event_type_function_entry = "FUNCTION_ENTRY";
+const char * const config_event_type_noop = "NOOP";
+const char * const config_event_type_syscall = "SYSCALL";
+const char * const config_event_type_kprobe = "KPROBE";
+const char * const config_event_type_kretprobe = "KRETPROBE";
+
+const char * const config_event_context_pid = "PID";
+const char * const config_event_context_procname = "PROCNAME";
+const char * const config_event_context_prio = "PRIO";
+const char * const config_event_context_nice = "NICE";
+const char * const config_event_context_vpid = "VPID";
+const char * const config_event_context_tid = "TID";
+const char * const config_event_context_vtid = "VTID";
+const char * const config_event_context_ppid = "PPID";
+const char * const config_event_context_vppid = "VPPID";
+const char * const config_event_context_pthread_id = "PTHREAD_ID";
+const char * const config_event_context_hostname = "HOSTNAME";
+const char * const config_event_context_ip = "IP";
+const char * const config_event_context_perf_thread_counter = "PERF_THREAD_COUNTER";
+const char * const config_event_context_app = "APP";
+const char * const config_event_context_interruptible = "INTERRUPTIBLE";
+const char * const config_event_context_preemptible = "PREEMPTIBLE";
+const char * const config_event_context_need_reschedule = "NEED_RESCHEDULE";
+const char * const config_event_context_migratable = "MIGRATABLE";
+const char * const config_event_context_callstack_user= "CALLSTACK_USER";
+const char * const config_event_context_callstack_kernel = "CALLSTACK_KERNEL";
+const char * const config_event_context_cgroup_ns = "CGROUP_NS";
+const char * const config_event_context_ipc_ns = "IPC_NS";
+const char * const config_event_context_mnt_ns = "MNT_NS";
+const char * const config_event_context_net_ns = "NET_NS";
+const char * const config_event_context_pid_ns = "PID_NS";
+const char * const config_event_context_time_ns = "TIME_NS";
+const char * const config_event_context_user_ns = "USER_NS";
+const char * const config_event_context_uts_ns = "UTS_NS";
+const char * const config_event_context_uid = "UID";
+const char * const config_event_context_euid = "EUID";
+const char * const config_event_context_suid = "SUID";
+const char * const config_event_context_gid = "GID";
+const char * const config_event_context_egid = "EGID";
+const char * const config_event_context_sgid = "SGID";
+const char * const config_event_context_vuid = "VUID";
+const char * const config_event_context_veuid = "VEUID";
+const char * const config_event_context_vsuid = "VSUID";
+const char * const config_event_context_vgid = "VGID";
+const char * const config_event_context_vegid = "VEGID";
+const char * const config_event_context_vsgid = "VSGID";
+
+/* Deprecated symbols */
+LTTNG_EXPORT const char *config_element_perf;
+
+enum process_event_node_phase {
+       CREATION = 0,
+       ENABLE = 1,
+};
+
+struct consumer_output {
+       int enabled;
+       char *path;
+       char *control_uri;
+       char *data_uri;
+};
+
+static int config_entry_handler_filter(struct handler_filter_args *args,
+               const char *section, const char *name, const char *value)
+{
+       int ret = 0;
+       struct config_entry entry = { section, name, value };
+
+       LTTNG_ASSERT(args);
+
+       if (!section || !name || !value) {
+               ret = -EIO;
+               goto end;
+       }
+
+       if (args->section) {
+               if (strcmp(args->section, section)) {
+                       goto end;
+               }
+       }
+
+       ret = args->handler(&entry, args->user_data);
+end:
+       return ret;
+}
+
+int config_get_section_entries(const char *override_path, const char *section,
+               config_entry_handler_cb handler, void *user_data)
+{
+       int ret = 0;
+       const char *path;
+       FILE *config_file = NULL;
+       struct handler_filter_args filter = { section, handler, user_data };
+
+       /* First, try system-wide conf. file. */
+       path = DEFAULT_DAEMON_SYSTEM_CONFIGPATH;
+
+       config_file = fopen(path, "r");
+       if (config_file) {
+               DBG("Loading daemon conf file at %s", path);
+               /*
+                * Return value is not very important here since error or not, we
+                * continue and try the next possible conf. file.
+                */
+               (void) ini_parse_file(config_file,
+                               (ini_entry_handler) config_entry_handler_filter,
+                               (void *) &filter);
+               fclose(config_file);
+       }
+
+       /* Second is the user local configuration. */
+       path = utils_get_home_dir();
+       if (path) {
+               char fullpath[PATH_MAX];
+
+               ret = snprintf(fullpath, sizeof(fullpath),
+                               DEFAULT_DAEMON_HOME_CONFIGPATH, path);
+               if (ret < 0) {
+                       PERROR("snprintf user conf. path");
+                       goto error;
+               }
+
+               config_file = fopen(fullpath, "r");
+               if (config_file) {
+                       DBG("Loading daemon user conf file at %s", path);
+                       /*
+                        * Return value is not very important here since error or not, we
+                        * continue and try the next possible conf. file.
+                        */
+                       (void) ini_parse_file(config_file,
+                                       (ini_entry_handler) config_entry_handler_filter,
+                                       (void *) &filter);
+                       fclose(config_file);
+               }
+       }
+
+       /* Final path is the one that the user might have provided. */
+       if (override_path) {
+               config_file = fopen(override_path, "r");
+               if (config_file) {
+                       DBG("Loading daemon command line conf file at %s", override_path);
+                       (void) ini_parse_file(config_file,
+                                       (ini_entry_handler) config_entry_handler_filter,
+                                       (void *) &filter);
+                       fclose(config_file);
+               } else {
+                       ERR("Failed to open daemon configuration file at %s",
+                               override_path);
+                       ret = -ENOENT;
+                       goto error;
+               }
+       }
+
+       /* Everything went well. */
+       ret = 0;
+
+error:
+       return ret;
+}
+
+int config_parse_value(const char *value)
+{
+       int i, ret = 0;
+       char *endptr, *lower_str;
+       size_t len;
+       unsigned long v;
+
+       len = strlen(value);
+       if (!len) {
+               ret = -1;
+               goto end;
+       }
+
+       v = strtoul(value, &endptr, 10);
+       if (endptr != value) {
+               ret = v;
+               goto end;
+       }
+
+       lower_str = (char *) zmalloc(len + 1);
+       if (!lower_str) {
+               PERROR("zmalloc");
+               ret = -errno;
+               goto end;
+       }
+
+       for (i = 0; i < len; i++) {
+               lower_str[i] = tolower(value[i]);
+       }
+
+       if (!strcmp(lower_str, config_str_yes) ||
+               !strcmp(lower_str, config_str_true) ||
+               !strcmp(lower_str, config_str_on)) {
+               ret = 1;
+       } else if (!strcmp(lower_str, config_str_no) ||
+               !strcmp(lower_str, config_str_false) ||
+               !strcmp(lower_str, config_str_off)) {
+               ret = 0;
+       } else {
+               ret = -1;
+       }
+
+       free(lower_str);
+end:
+       return ret;
+}
+
+/*
+ * Returns a xmlChar string which must be released using xmlFree().
+ */
+static xmlChar *encode_string(const char *in_str)
+{
+       xmlChar *out_str = NULL;
+       xmlCharEncodingHandlerPtr handler;
+       int out_len, ret, in_len;
+
+       LTTNG_ASSERT(in_str);
+
+       handler = xmlFindCharEncodingHandler(config_xml_encoding);
+       if (!handler) {
+               ERR("xmlFindCharEncodingHandler return NULL!. Configure issue!");
+               goto end;
+       }
+
+       in_len = strlen(in_str);
+       /*
+        * Add 1 byte for the NULL terminted character. The factor 4 here is
+        * used because UTF-8 characters can take up to 4 bytes.
+        */
+       out_len = (in_len * 4) + 1;
+       out_str = (xmlChar *) xmlMalloc(out_len);
+       if (!out_str) {
+               goto end;
+       }
+
+       ret = handler->input(out_str, &out_len, (const xmlChar *) in_str, &in_len);
+       if (ret < 0) {
+               xmlFree(out_str);
+               out_str = NULL;
+               goto end;
+       }
+
+       /* out_len is now the size of out_str */
+       out_str[out_len] = '\0';
+end:
+       return out_str;
+}
+
+struct config_writer *config_writer_create(int fd_output, int indent)
+{
+       int ret;
+       struct config_writer *writer;
+       xmlOutputBufferPtr buffer;
+
+       writer = (config_writer *) zmalloc(sizeof(struct config_writer));
+       if (!writer) {
+               PERROR("zmalloc config_writer_create");
+               goto end;
+       }
+
+       buffer = xmlOutputBufferCreateFd(fd_output, NULL);
+       if (!buffer) {
+               goto error_destroy;
+       }
+
+       writer->writer = xmlNewTextWriter(buffer);
+       ret = xmlTextWriterStartDocument(writer->writer, NULL,
+               config_xml_encoding, NULL);
+       if (ret < 0) {
+               goto error_destroy;
+       }
+
+       ret = xmlTextWriterSetIndentString(writer->writer,
+               BAD_CAST config_xml_indent_string);
+       if (ret) {
+               goto error_destroy;
+       }
+
+       ret = xmlTextWriterSetIndent(writer->writer, indent);
+       if (ret) {
+               goto error_destroy;
+       }
+
+end:
+       return writer;
+error_destroy:
+       config_writer_destroy(writer);
+       return NULL;
+}
+
+int config_writer_destroy(struct config_writer *writer)
+{
+       int ret = 0;
+
+       if (!writer) {
+               ret = -EINVAL;
+               goto end;
+       }
+
+       if (xmlTextWriterEndDocument(writer->writer) < 0) {
+               WARN("Could not close XML document");
+               ret = -EIO;
+       }
+
+       if (writer->writer) {
+               xmlFreeTextWriter(writer->writer);
+       }
+
+       free(writer);
+end:
+       return ret;
+}
+
+int config_writer_open_element(struct config_writer *writer,
+       const char *element_name)
+{
+       int ret;
+       xmlChar *encoded_element_name;
+
+       if (!writer || !writer->writer || !element_name || !element_name[0]) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_element_name = encode_string(element_name);
+       if (!encoded_element_name) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterStartElement(writer->writer, encoded_element_name);
+       xmlFree(encoded_element_name);
+end:
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_write_attribute(struct config_writer *writer,
+               const char *name, const char *value)
+{
+       int ret;
+       xmlChar *encoded_name = NULL;
+       xmlChar *encoded_value = NULL;
+
+       if (!writer || !writer->writer || !name || !name[0]) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_name = encode_string(name);
+       if (!encoded_name) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_value = encode_string(value);
+       if (!encoded_value) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterWriteAttribute(writer->writer, encoded_name,
+                       encoded_value);
+end:
+       xmlFree(encoded_name);
+       xmlFree(encoded_value);
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_close_element(struct config_writer *writer)
+{
+       int ret;
+
+       if (!writer || !writer->writer) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterEndElement(writer->writer);
+end:
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_write_element_unsigned_int(struct config_writer *writer,
+               const char *element_name, uint64_t value)
+{
+       int ret;
+       xmlChar *encoded_element_name;
+
+       if (!writer || !writer->writer || !element_name || !element_name[0]) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_element_name = encode_string(element_name);
+       if (!encoded_element_name) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterWriteFormatElement(writer->writer,
+               encoded_element_name, "%" PRIu64, value);
+       xmlFree(encoded_element_name);
+end:
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_write_element_signed_int(struct config_writer *writer,
+               const char *element_name, int64_t value)
+{
+       int ret;
+       xmlChar *encoded_element_name;
+
+       if (!writer || !writer->writer || !element_name || !element_name[0]) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_element_name = encode_string(element_name);
+       if (!encoded_element_name) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterWriteFormatElement(writer->writer,
+               encoded_element_name, "%" PRIi64, value);
+       xmlFree(encoded_element_name);
+end:
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_write_element_bool(struct config_writer *writer,
+               const char *element_name, int value)
+{
+       return config_writer_write_element_string(writer, element_name,
+               value ? config_xml_true : config_xml_false);
+}
+
+int config_writer_write_element_double(struct config_writer *writer,
+               const char *element_name,
+               double value)
+{
+       int ret;
+       xmlChar *encoded_element_name;
+
+       if (!writer || !writer->writer || !element_name || !element_name[0]) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_element_name = encode_string(element_name);
+       if (!encoded_element_name) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterWriteFormatElement(
+                       writer->writer, encoded_element_name, "%f", value);
+       xmlFree(encoded_element_name);
+end:
+       return ret >= 0 ? 0 : ret;
+}
+
+int config_writer_write_element_string(struct config_writer *writer,
+               const char *element_name, const char *value)
+{
+       int ret;
+       xmlChar *encoded_element_name = NULL;
+       xmlChar *encoded_value = NULL;
+
+       if (!writer || !writer->writer || !element_name || !element_name[0] ||
+               !value) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_element_name = encode_string(element_name);
+       if (!encoded_element_name) {
+               ret = -1;
+               goto end;
+       }
+
+       encoded_value = encode_string(value);
+       if (!encoded_value) {
+               ret = -1;
+               goto end;
+       }
+
+       ret = xmlTextWriterWriteElement(writer->writer, encoded_element_name,
+                       encoded_value);
+end:
+       xmlFree(encoded_element_name);
+       xmlFree(encoded_value);
+       return ret >= 0 ? 0 : ret;
+}
+
+static
+void xml_error_handler(void *ctx, const char *format, ...)
+{
+       char *errMsg;
+       va_list args;
+       int ret;
+
+       va_start(args, format);
+       ret = vasprintf(&errMsg, format, args);
+       va_end(args);
+       if (ret == -1) {
+               ERR("String allocation failed in xml error handler");
+               return;
+       }
+
+       fprintf(stderr, "XML Error: %s", errMsg);
+       free(errMsg);
+}
+
+static
+void fini_session_config_validation_ctx(
+       struct session_config_validation_ctx *ctx)
+{
+       if (ctx->parser_ctx) {
+               xmlSchemaFreeParserCtxt(ctx->parser_ctx);
+       }
+
+       if (ctx->schema) {
+               xmlSchemaFree(ctx->schema);
+       }
+
+       if (ctx->schema_validation_ctx) {
+               xmlSchemaFreeValidCtxt(ctx->schema_validation_ctx);
+       }
+
+       memset(ctx, 0, sizeof(struct session_config_validation_ctx));
+}
+
+static
+char *get_session_config_xsd_path(void)
+{
+       char *xsd_path;
+       const char *base_path = lttng_secure_getenv(DEFAULT_SESSION_CONFIG_XSD_PATH_ENV);
+       size_t base_path_len;
+       size_t max_path_len;
+
+       if (!base_path) {
+               base_path = DEFAULT_SESSION_CONFIG_XSD_PATH;
+       }
+
+       base_path_len = strlen(base_path);
+       max_path_len = base_path_len +
+               sizeof(DEFAULT_SESSION_CONFIG_XSD_FILENAME) + 1;
+       xsd_path = (char *) zmalloc(max_path_len);
+       if (!xsd_path) {
+               goto end;
+       }
+
+       strcpy(xsd_path, base_path);
+       if (xsd_path[base_path_len - 1] != '/') {
+               xsd_path[base_path_len++] = '/';
+       }
+
+       strcpy(xsd_path + base_path_len, DEFAULT_SESSION_CONFIG_XSD_FILENAME);
+end:
+       return xsd_path;
+}
+
+static
+int init_session_config_validation_ctx(
+       struct session_config_validation_ctx *ctx)
+{
+       int ret;
+       char *xsd_path = get_session_config_xsd_path();
+
+       if (!xsd_path) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       ctx->parser_ctx = xmlSchemaNewParserCtxt(xsd_path);
+       if (!ctx->parser_ctx) {
+               ERR("XSD parser context creation failed");
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+       xmlSchemaSetParserErrors(ctx->parser_ctx, xml_error_handler,
+               xml_error_handler, NULL);
+
+       ctx->schema = xmlSchemaParse(ctx->parser_ctx);
+       if (!ctx->schema) {
+               ERR("XSD parsing failed");
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       ctx->schema_validation_ctx = xmlSchemaNewValidCtxt(ctx->schema);
+       if (!ctx->schema_validation_ctx) {
+               ERR("XSD validation context creation failed");
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       xmlSchemaSetValidErrors(ctx->schema_validation_ctx, xml_error_handler,
+                       xml_error_handler, NULL);
+       ret = 0;
+
+end:
+       if (ret) {
+               fini_session_config_validation_ctx(ctx);
+       }
+
+       free(xsd_path);
+       return ret;
+}
+
+static
+int parse_uint(xmlChar *str, uint64_t *val)
+{
+       int ret;
+       char *endptr;
+
+       if (!str || !val) {
+               ret = -1;
+               goto end;
+       }
+
+       *val = strtoull((const char *) str, &endptr, 10);
+       if (!endptr || *endptr) {
+               ret = -1;
+       } else {
+               ret = 0;
+       }
+
+end:
+       return ret;
+}
+
+static
+int parse_int(xmlChar *str, int64_t *val)
+{
+       int ret;
+       char *endptr;
+
+       if (!str || !val) {
+               ret = -1;
+               goto end;
+       }
+
+       *val = strtoll((const char *) str, &endptr, 10);
+       if (!endptr || *endptr) {
+               ret = -1;
+       } else {
+               ret = 0;
+       }
+
+end:
+       return ret;
+}
+
+static
+int parse_bool(xmlChar *str, int *val)
+{
+       int ret = 0;
+
+       if (!str || !val) {
+               ret = -1;
+               goto end;
+       }
+
+       if (!strcmp((const char *) str, config_xml_true) ||
+                       !strcmp((const char *) str, "1")) {
+               *val = 1;
+       } else if (!strcmp((const char *) str, config_xml_false) ||
+                       !strcmp((const char *) str, "0")) {
+               *val = 0;
+       } else {
+               WARN("Invalid boolean value encountered (%s).",
+                       (const char *) str);
+               ret = -1;
+       }
+end:
+       return ret;
+}
+
+static
+int get_domain_type(xmlChar *domain)
+{
+       int ret;
+
+       if (!domain) {
+               goto error;
+       }
+
+       if (!strcmp((char *) domain, config_domain_type_kernel)) {
+               ret = LTTNG_DOMAIN_KERNEL;
+       } else if (!strcmp((char *) domain, config_domain_type_ust)) {
+               ret = LTTNG_DOMAIN_UST;
+       } else if (!strcmp((char *) domain, config_domain_type_jul)) {
+               ret = LTTNG_DOMAIN_JUL;
+       } else if (!strcmp((char *) domain, config_domain_type_log4j)) {
+               ret = LTTNG_DOMAIN_LOG4J;
+       } else if (!strcmp((char *) domain, config_domain_type_python)) {
+               ret = LTTNG_DOMAIN_PYTHON;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int get_buffer_type(xmlChar *buffer_type)
+{
+       int ret;
+
+       if (!buffer_type) {
+               goto error;
+       }
+
+       if (!strcmp((char *) buffer_type, config_buffer_type_global)) {
+               ret = LTTNG_BUFFER_GLOBAL;
+       } else if (!strcmp((char *) buffer_type, config_buffer_type_per_uid)) {
+               ret = LTTNG_BUFFER_PER_UID;
+       } else if (!strcmp((char *) buffer_type, config_buffer_type_per_pid)) {
+               ret = LTTNG_BUFFER_PER_PID;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int get_overwrite_mode(xmlChar *overwrite_mode)
+{
+       int ret;
+
+       if (!overwrite_mode) {
+               goto error;
+       }
+
+       if (!strcmp((char *) overwrite_mode, config_overwrite_mode_overwrite)) {
+               ret = 1;
+       } else if (!strcmp((char *) overwrite_mode,
+               config_overwrite_mode_discard)) {
+               ret = 0;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int get_output_type(xmlChar *output_type)
+{
+       int ret;
+
+       if (!output_type) {
+               goto error;
+       }
+
+       if (!strcmp((char *) output_type, config_output_type_mmap)) {
+               ret = LTTNG_EVENT_MMAP;
+       } else if (!strcmp((char *) output_type, config_output_type_splice)) {
+               ret = LTTNG_EVENT_SPLICE;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int get_event_type(xmlChar *event_type)
+{
+       int ret;
+
+       if (!event_type) {
+               goto error;
+       }
+
+       if (!strcmp((char *) event_type, config_event_type_all)) {
+               ret = LTTNG_EVENT_ALL;
+       } else if (!strcmp((char *) event_type, config_event_type_tracepoint)) {
+               ret = LTTNG_EVENT_TRACEPOINT;
+       } else if (!strcmp((char *) event_type, config_event_type_probe)) {
+               ret = LTTNG_EVENT_PROBE;
+       } else if (!strcmp((char *) event_type,
+                               config_event_type_userspace_probe)) {
+               ret = LTTNG_EVENT_USERSPACE_PROBE;
+       } else if (!strcmp((char *) event_type, config_event_type_function)) {
+               ret = LTTNG_EVENT_FUNCTION;
+       } else if (!strcmp((char *) event_type,
+                               config_event_type_function_entry)) {
+               ret = LTTNG_EVENT_FUNCTION_ENTRY;
+       } else if (!strcmp((char *) event_type, config_event_type_noop)) {
+               ret = LTTNG_EVENT_NOOP;
+       } else if (!strcmp((char *) event_type, config_event_type_syscall)) {
+               ret = LTTNG_EVENT_SYSCALL;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int get_loglevel_type(xmlChar *loglevel_type)
+{
+       int ret;
+
+       if (!loglevel_type) {
+               goto error;
+       }
+
+       if (!strcmp((char *) loglevel_type, config_loglevel_type_all)) {
+               ret = LTTNG_EVENT_LOGLEVEL_ALL;
+       } else if (!strcmp((char *) loglevel_type,
+               config_loglevel_type_range)) {
+               ret = LTTNG_EVENT_LOGLEVEL_RANGE;
+       } else if (!strcmp((char *) loglevel_type,
+               config_loglevel_type_single)) {
+               ret = LTTNG_EVENT_LOGLEVEL_SINGLE;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+/*
+ * Return the context type or -1 on error.
+ */
+static
+int get_context_type(xmlChar *context_type)
+{
+       int ret;
+
+       if (!context_type) {
+               goto error;
+       }
+
+       if (!strcmp((char *) context_type, config_event_context_pid)) {
+               ret = LTTNG_EVENT_CONTEXT_PID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_procname)) {
+               ret = LTTNG_EVENT_CONTEXT_PROCNAME;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_prio)) {
+               ret = LTTNG_EVENT_CONTEXT_PRIO;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_nice)) {
+               ret = LTTNG_EVENT_CONTEXT_NICE;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vpid)) {
+               ret = LTTNG_EVENT_CONTEXT_VPID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_tid)) {
+               ret = LTTNG_EVENT_CONTEXT_TID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vtid)) {
+               ret = LTTNG_EVENT_CONTEXT_VTID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_ppid)) {
+               ret = LTTNG_EVENT_CONTEXT_PPID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vppid)) {
+               ret = LTTNG_EVENT_CONTEXT_VPPID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_pthread_id)) {
+               ret = LTTNG_EVENT_CONTEXT_PTHREAD_ID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_hostname)) {
+               ret = LTTNG_EVENT_CONTEXT_HOSTNAME;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_ip)) {
+               ret = LTTNG_EVENT_CONTEXT_IP;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_interruptible)) {
+               ret = LTTNG_EVENT_CONTEXT_INTERRUPTIBLE;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_preemptible)) {
+               ret = LTTNG_EVENT_CONTEXT_PREEMPTIBLE;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_need_reschedule)) {
+               ret = LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_migratable)) {
+               ret = LTTNG_EVENT_CONTEXT_MIGRATABLE;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_callstack_user)) {
+               ret = LTTNG_EVENT_CONTEXT_CALLSTACK_USER;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_callstack_kernel)) {
+               ret = LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_cgroup_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_CGROUP_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_ipc_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_IPC_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_mnt_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_MNT_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_net_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_NET_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_pid_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_PID_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_time_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_TIME_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_user_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_USER_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_uts_ns)) {
+               ret = LTTNG_EVENT_CONTEXT_UTS_NS;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_uid)) {
+               ret = LTTNG_EVENT_CONTEXT_UID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_euid)) {
+               ret = LTTNG_EVENT_CONTEXT_EUID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_suid)) {
+               ret = LTTNG_EVENT_CONTEXT_SUID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_gid)) {
+               ret = LTTNG_EVENT_CONTEXT_GID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_egid)) {
+               ret = LTTNG_EVENT_CONTEXT_EGID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_sgid)) {
+               ret = LTTNG_EVENT_CONTEXT_SGID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vuid)) {
+               ret = LTTNG_EVENT_CONTEXT_VUID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_veuid)) {
+               ret = LTTNG_EVENT_CONTEXT_VEUID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vsuid)) {
+               ret = LTTNG_EVENT_CONTEXT_VSUID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vgid)) {
+               ret = LTTNG_EVENT_CONTEXT_VGID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vegid)) {
+               ret = LTTNG_EVENT_CONTEXT_VEGID;
+       } else if (!strcmp((char *) context_type,
+               config_event_context_vsgid)) {
+               ret = LTTNG_EVENT_CONTEXT_VSGID;
+       } else {
+               goto error;
+       }
+
+       return ret;
+error:
+       return -1;
+}
+
+static
+int init_domain(xmlNodePtr domain_node, struct lttng_domain *domain)
+{
+       int ret;
+       xmlNodePtr node;
+
+       for (node = xmlFirstElementChild(domain_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name, config_element_type)) {
+                       /* domain type */
+                       xmlChar *node_content = xmlNodeGetContent(node);
+                       if (!node_content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = get_domain_type(node_content);
+                       free(node_content);
+                       if (ret < 0) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       domain->type = (lttng_domain_type) ret;
+               } else if (!strcmp((const char *) node->name,
+                       config_element_buffer_type)) {
+                       /* buffer type */
+                       xmlChar *node_content = xmlNodeGetContent(node);
+                       if (!node_content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = get_buffer_type(node_content);
+                       free(node_content);
+                       if (ret < 0) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       domain->buf_type = (lttng_buffer_type) ret;
+               }
+       }
+       ret = 0;
+end:
+       return ret;
+}
+
+static
+int get_net_output_uris(xmlNodePtr net_output_node, char **control_uri,
+       char **data_uri)
+{
+       xmlNodePtr node;
+
+       for (node = xmlFirstElementChild(net_output_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name, config_element_control_uri)) {
+                       /* control_uri */
+                       *control_uri = (char *) xmlNodeGetContent(node);
+                       if (!*control_uri) {
+                               break;
+                       }
+               } else {
+                       /* data_uri */
+                       *data_uri = (char *) xmlNodeGetContent(node);
+                       if (!*data_uri) {
+                               break;
+                       }
+               }
+       }
+
+       return *control_uri || *data_uri ? 0 : -LTTNG_ERR_LOAD_INVALID_CONFIG;
+}
+
+static
+int process_consumer_output(xmlNodePtr consumer_output_node,
+       struct consumer_output *output)
+{
+       int ret;
+       xmlNodePtr node;
+
+       LTTNG_ASSERT(output);
+
+       for (node = xmlFirstElementChild(consumer_output_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name, config_element_enabled)) {
+                       xmlChar *enabled_str = xmlNodeGetContent(node);
+
+                       /* enabled */
+                       if (!enabled_str) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = parse_bool(enabled_str, &output->enabled);
+                       free(enabled_str);
+                       if (ret) {
+                               goto end;
+                       }
+               } else {
+                       xmlNodePtr output_type_node;
+
+                       /* destination */
+                       output_type_node = xmlFirstElementChild(node);
+                       if (!output_type_node) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       if (!strcmp((const char *) output_type_node->name,
+                                       config_element_path)) {
+                               /* path */
+                               output->path = (char *) xmlNodeGetContent(output_type_node);
+                               if (!output->path) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+                       } else {
+                               /* net_output */
+                               ret = get_net_output_uris(output_type_node,
+                                               &output->control_uri, &output->data_uri);
+                               if (ret) {
+                                       goto end;
+                               }
+                       }
+               }
+       }
+       ret = 0;
+
+end:
+       if (ret) {
+               free(output->path);
+               free(output->control_uri);
+               free(output->data_uri);
+               memset(output, 0, sizeof(struct consumer_output));
+       }
+       return ret;
+}
+
+static
+int create_session_net_output(const char *name, const char *control_uri,
+               const char *data_uri)
+{
+       int ret;
+       struct lttng_handle *handle;
+       const char *uri = NULL;
+
+       LTTNG_ASSERT(name);
+
+       handle = lttng_create_handle(name, NULL);
+       if (!handle) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       if (!control_uri || !data_uri) {
+               uri = control_uri ? control_uri : data_uri;
+               control_uri = uri;
+               data_uri = uri;
+       }
+
+       ret = lttng_set_consumer_url(handle, control_uri, data_uri);
+       lttng_destroy_handle(handle);
+end:
+       return ret;
+}
+
+static
+int create_snapshot_session(const char *session_name, xmlNodePtr output_node,
+               const struct config_load_session_override_attr *overrides)
+{
+       int ret;
+       xmlNodePtr node = NULL;
+       xmlNodePtr snapshot_output_list_node;
+       xmlNodePtr snapshot_output_node;
+
+       LTTNG_ASSERT(session_name);
+
+       ret = lttng_create_session_snapshot(session_name, NULL);
+       if (ret) {
+               goto end;
+       }
+
+       if (!output_node) {
+               goto end;
+       }
+
+       snapshot_output_list_node = xmlFirstElementChild(output_node);
+
+       /* Parse and create snapshot outputs */
+
+       for (snapshot_output_node =
+                       xmlFirstElementChild(snapshot_output_list_node);
+                       snapshot_output_node; snapshot_output_node =
+                       xmlNextElementSibling(snapshot_output_node)) {
+               char *name = NULL;
+               uint64_t max_size = UINT64_MAX;
+               struct consumer_output output = { 0 };
+               struct lttng_snapshot_output *snapshot_output = NULL;
+               const char *control_uri = NULL;
+               const char *data_uri = NULL;
+               const char *path = NULL;
+
+               for (node = xmlFirstElementChild(snapshot_output_node); node;
+                               node = xmlNextElementSibling(node)) {
+                       if (!strcmp((const char *) node->name,
+                               config_element_name)) {
+                               /* name */
+                               name = (char *) xmlNodeGetContent(node);
+                               if (!name) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto error_snapshot_output;
+                               }
+                       } else if (!strcmp((const char *) node->name,
+                               config_element_max_size)) {
+                               xmlChar *content = xmlNodeGetContent(node);
+
+                               /* max_size */
+                               if (!content) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto error_snapshot_output;
+                               }
+                               ret = parse_uint(content, &max_size);
+                               free(content);
+                               if (ret) {
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto error_snapshot_output;
+                               }
+                       } else {
+                               /* consumer_output */
+                               ret = process_consumer_output(node, &output);
+                               if (ret) {
+                                       goto error_snapshot_output;
+                               }
+                       }
+               }
+
+               control_uri = output.control_uri;
+               data_uri = output.data_uri;
+               path = output.path;
+
+               if (overrides) {
+                       if (overrides->path_url) {
+                               path = overrides->path_url;
+                               /* Control/data_uri are null */
+                               control_uri = NULL;
+                               data_uri = NULL;
+                       } else {
+                               if (overrides->ctrl_url) {
+                                       control_uri = overrides->ctrl_url;
+                                       /* path is null */
+                                       path = NULL;
+                               }
+                               if (overrides->data_url) {
+                                       data_uri = overrides->data_url;
+                                       /* path is null */
+                                       path = NULL;
+                               }
+                       }
+               }
+
+               snapshot_output = lttng_snapshot_output_create();
+               if (!snapshot_output) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto error_snapshot_output;
+               }
+
+               ret = lttng_snapshot_output_set_name(name, snapshot_output);
+               if (ret) {
+                       goto error_snapshot_output;
+               }
+
+               ret = lttng_snapshot_output_set_size(max_size, snapshot_output);
+               if (ret) {
+                       goto error_snapshot_output;
+               }
+
+               if (path) {
+                       ret = lttng_snapshot_output_set_ctrl_url(path,
+                                       snapshot_output);
+                       if (ret) {
+                               goto error_snapshot_output;
+                       }
+               } else {
+                       if (control_uri) {
+                               ret = lttng_snapshot_output_set_ctrl_url(control_uri,
+                                               snapshot_output);
+                               if (ret) {
+                                       goto error_snapshot_output;
+                               }
+                       }
+
+                       if (data_uri) {
+                               ret = lttng_snapshot_output_set_data_url(data_uri,
+                                               snapshot_output);
+                               if (ret) {
+                                       goto error_snapshot_output;
+                               }
+                       }
+               }
+
+               ret = lttng_snapshot_add_output(session_name, snapshot_output);
+error_snapshot_output:
+               free(name);
+               free(output.path);
+               free(output.control_uri);
+               free(output.data_uri);
+               lttng_snapshot_output_destroy(snapshot_output);
+               if (ret) {
+                       goto end;
+               }
+       }
+end:
+       return ret;
+}
+
+static
+int create_session(const char *name,
+       xmlNodePtr output_node,
+       uint64_t live_timer_interval,
+       const struct config_load_session_override_attr *overrides)
+{
+       int ret;
+       struct consumer_output output = { 0 };
+       xmlNodePtr consumer_output_node;
+       const char *control_uri = NULL;
+       const char *data_uri = NULL;
+       const char *path = NULL;
+
+       LTTNG_ASSERT(name);
+
+       if (output_node) {
+               consumer_output_node = xmlFirstElementChild(output_node);
+               if (!consumer_output_node) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               if (strcmp((const char *) consumer_output_node->name,
+                       config_element_consumer_output)) {
+                       WARN("Invalid output type, expected %s node",
+                               config_element_consumer_output);
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               ret = process_consumer_output(consumer_output_node, &output);
+               if (ret) {
+                       goto end;
+               }
+       }
+
+       control_uri = output.control_uri;
+       data_uri = output.data_uri;
+       path = output.path;
+
+       /* Check for override and apply them */
+       if (overrides) {
+               if (overrides->path_url) {
+                       path = overrides->path_url;
+                       /* control/data_uri are null */;
+                       control_uri = NULL;
+                       data_uri = NULL;
+               } else {
+                       if (overrides->ctrl_url) {
+                               control_uri = overrides->ctrl_url;
+                               /* path is null */
+                               path = NULL;
+                       }
+                       if (overrides->data_url) {
+                               data_uri = overrides->data_url;
+                               /* path is null */
+                               path = NULL;
+                       }
+               }
+       }
+
+
+       if (live_timer_interval != UINT64_MAX && !control_uri && !data_uri) {
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       if (control_uri || data_uri) {
+               /* network destination */
+               if (live_timer_interval && live_timer_interval != UINT64_MAX) {
+                       /*
+                        * URLs are provided for sure since the test above make sure that
+                        * with a live timer the data and control URIs are provided. So,
+                        * NULL is passed here and will be set right after.
+                        */
+                       ret = lttng_create_session_live(name, NULL, live_timer_interval);
+               } else {
+                       ret = lttng_create_session(name, NULL);
+               }
+               if (ret) {
+                       goto end;
+               }
+
+               ret = create_session_net_output(name, control_uri, data_uri);
+               if (ret) {
+                       goto end;
+               }
+
+       } else {
+               /* either local output or no output */
+               ret = lttng_create_session(name, path);
+               if (ret) {
+                       goto end;
+               }
+       }
+end:
+       free(output.path);
+       free(output.control_uri);
+       free(output.data_uri);
+       return ret;
+}
+
+static
+struct lttng_userspace_probe_location *
+process_userspace_probe_function_attribute_node(
+               xmlNodePtr attribute_node)
+{
+       xmlNodePtr function_attribute_node;
+       char *function_name = NULL, *binary_path = NULL;
+       struct lttng_userspace_probe_location *location = NULL;
+       struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
+
+       /*
+        * Process userspace probe location function attributes. The order of
+        * the fields are not guaranteed so we need to iterate over all fields
+        * and check at the end if everything we need for this location type is
+        * there.
+        */
+       for (function_attribute_node =
+                       xmlFirstElementChild(attribute_node);
+                       function_attribute_node;
+                       function_attribute_node = xmlNextElementSibling(
+                               function_attribute_node)) {
+               /* Handle function name, binary path and lookup method. */
+               if (!strcmp((const char *) function_attribute_node->name,
+                                       config_element_userspace_probe_function_location_function_name)) {
+                       function_name = (char *) xmlNodeGetContent(function_attribute_node);
+                       if (!function_name) {
+                               goto error;
+                       }
+               } else if (!strcmp((const char *) function_attribute_node->name,
+                                       config_element_userspace_probe_location_binary_path)) {
+                       binary_path = (char *) xmlNodeGetContent(function_attribute_node);
+                       if (!binary_path) {
+                               goto error;
+                       }
+               } else if (!strcmp((const char *) function_attribute_node->name,
+                                       config_element_userspace_probe_lookup)) {
+                       char *lookup_method_name;
+
+                       lookup_method_name = (char *) xmlNodeGetContent(
+                                       function_attribute_node);
+                       if (!lookup_method_name) {
+                               goto error;
+                       }
+
+                       /*
+                        * function_default lookup method defaults to
+                        * function_elf lookup method at the moment.
+                        */
+                       if (!strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_elf)
+                                       || !strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_default)) {
+                               lookup_method = lttng_userspace_probe_location_lookup_method_function_elf_create();
+                               if (!lookup_method) {
+                                       PERROR("Error creating function default/ELF lookup method");
+                               }
+                       } else {
+                               WARN("Unknown function lookup method");
+                       }
+
+                       free(lookup_method_name);
+                       if (!lookup_method) {
+                               goto error;
+                       }
+               } else {
+                       goto error;
+               }
+
+               /* Check if all the necessary fields were found. */
+               if (binary_path && function_name && lookup_method) {
+                       /* Ownership of lookup_method is transferred. */
+                       location =
+                               lttng_userspace_probe_location_function_create(
+                                               binary_path, function_name,
+                                               lookup_method);
+                       lookup_method = NULL;
+                       goto error;
+               }
+       }
+error:
+       lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
+       free(binary_path);
+       free(function_name);
+       return location;
+}
+
+static
+struct lttng_userspace_probe_location *
+process_userspace_probe_tracepoint_attribute_node(
+               xmlNodePtr attribute_node)
+{
+       xmlNodePtr tracepoint_attribute_node;
+       char *probe_name = NULL, *provider_name = NULL, *binary_path = NULL;
+       struct lttng_userspace_probe_location *location = NULL;
+       struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
+
+       /*
+        * Process userspace probe location tracepoint attributes. The order of
+        * the fields are not guaranteed so we need to iterate over all fields
+        * and check at the end if everything we need for this location type is
+        * there.
+        */
+       for (tracepoint_attribute_node =
+               xmlFirstElementChild(attribute_node); tracepoint_attribute_node;
+               tracepoint_attribute_node = xmlNextElementSibling(
+                               tracepoint_attribute_node)) {
+               if (!strcmp((const char *) tracepoint_attribute_node->name,
+                                       config_element_userspace_probe_tracepoint_location_probe_name)) {
+                       probe_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
+                       if (!probe_name) {
+                               goto error;
+                       }
+               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
+                                       config_element_userspace_probe_tracepoint_location_provider_name)) {
+                       provider_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
+                       if (!provider_name) {
+                               goto error;
+                       }
+               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
+                                       config_element_userspace_probe_location_binary_path)) {
+                       binary_path = (char *) xmlNodeGetContent(tracepoint_attribute_node);
+                       if (!binary_path) {
+                               goto error;
+                       }
+               } else if (!strcmp((const char *) tracepoint_attribute_node->name,
+                                       config_element_userspace_probe_lookup)) {
+                       char *lookup_method_name;
+
+                       lookup_method_name = (char *) xmlNodeGetContent(
+                                       tracepoint_attribute_node);
+                       if (!lookup_method_name) {
+                               goto error;
+                       }
+
+                       if (!strcmp(lookup_method_name,
+                                               config_element_userspace_probe_lookup_tracepoint_sdt)) {
+                               lookup_method =
+                                       lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create();
+                               if (!lookup_method) {
+                                       PERROR("Error creating tracepoint SDT lookup method");
+                               }
+                       } else {
+                               WARN("Unknown tracepoint lookup method");
+                       }
+
+                       free(lookup_method_name);
+                       if (!lookup_method) {
+                               goto error;
+                       }
+               } else {
+                       WARN("Unknown tracepoint attribute");
+                       goto error;
+               }
+
+               /* Check if all the necessary fields were found. */
+               if (binary_path && provider_name && probe_name && lookup_method) {
+                       /* Ownership of lookup_method is transferred. */
+                       location =
+                               lttng_userspace_probe_location_tracepoint_create(
+                                               binary_path, provider_name,
+                                               probe_name, lookup_method);
+                       lookup_method = NULL;
+                       goto error;
+               }
+       }
+error:
+       lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
+       free(binary_path);
+       free(provider_name);
+       free(probe_name);
+       return location;
+}
+
+static
+int process_probe_attribute_node(xmlNodePtr probe_attribute_node,
+       struct lttng_event_probe_attr *attr)
+{
+       int ret;
+
+       LTTNG_ASSERT(probe_attribute_node);
+       LTTNG_ASSERT(attr);
+
+       if (!strcmp((const char *) probe_attribute_node->name,
+               config_element_address)) {
+               xmlChar *content;
+               uint64_t addr = 0;
+
+               /* addr */
+               content = xmlNodeGetContent(probe_attribute_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &addr);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               attr->addr = addr;
+       } else if (!strcmp((const char *) probe_attribute_node->name,
+               config_element_offset)) {
+               xmlChar *content;
+               uint64_t offset = 0;
+
+               /* offset */
+               content = xmlNodeGetContent(probe_attribute_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &offset);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               attr->offset = offset;
+       } else if (!strcmp((const char *) probe_attribute_node->name,
+               config_element_symbol_name)) {
+               xmlChar *content;
+
+               /* symbol_name */
+               content = xmlNodeGetContent(probe_attribute_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = lttng_strncpy(attr->symbol_name,
+                               (const char *) content,
+                               LTTNG_SYMBOL_NAME_LEN);
+               if (ret == -1) {
+                       ERR("symbol name \"%s\"'s length (%zu) exceeds the maximal permitted length (%d) in session configuration",
+                                       (const char *) content,
+                                       strlen((const char *) content),
+                                       LTTNG_SYMBOL_NAME_LEN);
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       free(content);
+                       goto end;
+               }
+               free(content);
+       }
+       ret = 0;
+end:
+       return ret;
+}
+
+static
+int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
+       const char *channel_name, const enum process_event_node_phase phase)
+{
+       int ret = 0, i;
+       xmlNodePtr node;
+       struct lttng_event *event;
+       char **exclusions = NULL;
+       unsigned long exclusion_count = 0;
+       char *filter_expression = NULL;
+
+       LTTNG_ASSERT(event_node);
+       LTTNG_ASSERT(handle);
+       LTTNG_ASSERT(channel_name);
+
+       event = lttng_event_create();
+       if (!event) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       /* Initialize default log level which varies by domain */
+       switch (handle->domain.type)
+       {
+       case LTTNG_DOMAIN_JUL:
+               event->loglevel = LTTNG_LOGLEVEL_JUL_ALL;
+               break;
+       case LTTNG_DOMAIN_LOG4J:
+               event->loglevel = LTTNG_LOGLEVEL_LOG4J_ALL;
+               break;
+       case LTTNG_DOMAIN_PYTHON:
+               event->loglevel = LTTNG_LOGLEVEL_PYTHON_DEBUG;
+               break;
+       case LTTNG_DOMAIN_UST:
+       case LTTNG_DOMAIN_KERNEL:
+               event->loglevel = LTTNG_LOGLEVEL_DEBUG;
+               break;
+       default:
+               abort();
+       }
+
+       for (node = xmlFirstElementChild(event_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name, config_element_name)) {
+                       xmlChar *content;
+
+                       /* name */
+                       content = xmlNodeGetContent(node);
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = lttng_strncpy(event->name,
+                                       (const char *) content,
+                                       LTTNG_SYMBOL_NAME_LEN);
+                       if (ret == -1) {
+                               WARN("Event \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
+                                               (const char *) content,
+                                               strlen((const char *) content),
+                                               LTTNG_SYMBOL_NAME_LEN);
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               free(content);
+                               goto end;
+                       }
+                       free(content);
+               } else if (!strcmp((const char *) node->name,
+                       config_element_enabled)) {
+                       xmlChar *content = xmlNodeGetContent(node);
+
+                       /* enabled */
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = parse_bool(content, &event->enabled);
+                       free(content);
+                       if (ret) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+               } else if (!strcmp((const char *) node->name,
+                       config_element_type)) {
+                       xmlChar *content = xmlNodeGetContent(node);
+
+                       /* type */
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = get_event_type(content);
+                       free(content);
+                       if (ret < 0) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       event->type = (lttng_event_type) ret;
+               } else if (!strcmp((const char *) node->name,
+                       config_element_loglevel_type)) {
+                       xmlChar *content = xmlNodeGetContent(node);
+
+                       /* loglevel_type */
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = get_loglevel_type(content);
+                       free(content);
+                       if (ret < 0) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       event->loglevel_type = (lttng_loglevel_type) ret;
+               } else if (!strcmp((const char *) node->name,
+                       config_element_loglevel)) {
+                       xmlChar *content;
+                       int64_t loglevel = 0;
+
+                       /* loglevel */
+                       content = xmlNodeGetContent(node);
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = parse_int(content, &loglevel);
+                       free(content);
+                       if (ret) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       if (loglevel > INT_MAX || loglevel < INT_MIN) {
+                               WARN("loglevel out of range.");
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       event->loglevel = loglevel;
+               } else if (!strcmp((const char *) node->name,
+                       config_element_filter)) {
+                       xmlChar *content =
+                               xmlNodeGetContent(node);
+
+                       /* filter */
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       free(filter_expression);
+                       filter_expression = strdup((char *) content);
+                       free(content);
+                       if (!filter_expression) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+               } else if (!strcmp((const char *) node->name,
+                       config_element_exclusions)) {
+                       xmlNodePtr exclusion_node;
+                       int exclusion_index = 0;
+
+                       /* exclusions */
+                       if (exclusions) {
+                               /*
+                                * Exclusions has already been initialized,
+                                * invalid file.
+                                */
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       exclusion_count = xmlChildElementCount(node);
+                       if (!exclusion_count) {
+                               continue;
+                       }
+
+                       exclusions = (char **) zmalloc(exclusion_count * sizeof(char *));
+                       if (!exclusions) {
+                               exclusion_count = 0;
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       for (exclusion_node = xmlFirstElementChild(node); exclusion_node;
+                                       exclusion_node = xmlNextElementSibling(exclusion_node)) {
+                               xmlChar *content =
+                                       xmlNodeGetContent(exclusion_node);
+
+                               if (!content) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+
+                               exclusions[exclusion_index] = strdup((const char *) content);
+                               free(content);
+                               if (!exclusions[exclusion_index]) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+                               exclusion_index++;
+                       }
+
+                       event->exclusion = 1;
+               } else if (!strcmp((const char *) node->name,
+                       config_element_attributes)) {
+                       xmlNodePtr attribute_node = xmlFirstElementChild(node);
+
+                       /* attributes */
+                       if (!attribute_node) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       if (!strcmp((const char *) attribute_node->name,
+                                               config_element_probe_attributes)) {
+                               xmlNodePtr probe_attribute_node;
+
+                               /* probe_attributes */
+                               for (probe_attribute_node =
+                                       xmlFirstElementChild(attribute_node); probe_attribute_node;
+                                       probe_attribute_node = xmlNextElementSibling(
+                                                       probe_attribute_node)) {
+
+                                       ret = process_probe_attribute_node(probe_attribute_node,
+                                                       &event->attr.probe);
+                                       if (ret) {
+                                               goto end;
+                                       }
+                               }
+                       } else if (!strcmp((const char *) attribute_node->name,
+                                               config_element_function_attributes)) {
+                               size_t sym_len;
+                               xmlChar *content;
+                               xmlNodePtr symbol_node = xmlFirstElementChild(attribute_node);
+
+                               /* function_attributes */
+                               content = xmlNodeGetContent(symbol_node);
+                               if (!content) {
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               sym_len = strlen((char *) content);
+                               if (sym_len >= LTTNG_SYMBOL_NAME_LEN) {
+                                       WARN("Function name too long.");
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       free(content);
+                                       goto end;
+                               }
+
+                               ret = lttng_strncpy(
+                                               event->attr.ftrace.symbol_name,
+                                               (char *) content, sym_len);
+                               if (ret == -1) {
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       free(content);
+                                       goto end;
+                               }
+                               free(content);
+                       } else if (!strcmp((const char *) attribute_node->name,
+                                               config_element_userspace_probe_tracepoint_attributes)) {
+                               struct lttng_userspace_probe_location *location;
+
+                               location = process_userspace_probe_tracepoint_attribute_node(attribute_node);
+                               if (!location) {
+                                       WARN("Error processing userspace probe tracepoint attribute");
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+                               ret = lttng_event_set_userspace_probe_location(
+                                               event, location);
+                               if (ret) {
+                                       WARN("Error setting userspace probe location field");
+                                       lttng_userspace_probe_location_destroy(
+                                                       location);
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+                       } else if (!strcmp((const char *) attribute_node->name,
+                                               config_element_userspace_probe_function_attributes)) {
+                               struct lttng_userspace_probe_location *location;
+
+                               location =
+                                       process_userspace_probe_function_attribute_node(
+                                                       attribute_node);
+                               if (!location) {
+                                       WARN("Error processing userspace probe function attribute");
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               ret = lttng_event_set_userspace_probe_location(
+                                               event, location);
+                               if (ret) {
+                                       WARN("Error setting userspace probe location field");
+                                       lttng_userspace_probe_location_destroy(
+                                                       location);
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+                       } else {
+                               /* Unknown event attribute. */
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+               }
+       }
+
+       if ((event->enabled && phase == ENABLE) || phase == CREATION) {
+               ret = lttng_enable_event_with_exclusions(handle, event, channel_name,
+                               filter_expression, exclusion_count, exclusions);
+               if (ret < 0) {
+                       WARN("Enabling event (name:%s) on load failed.", event->name);
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       }
+       ret = 0;
+end:
+       for (i = 0; i < exclusion_count; i++) {
+               free(exclusions[i]);
+       }
+
+       lttng_event_destroy(event);
+       free(exclusions);
+       free(filter_expression);
+       return ret;
+}
+
+static
+int process_events_node(xmlNodePtr events_node, struct lttng_handle *handle,
+       const char *channel_name)
+{
+       int ret = 0;
+       struct lttng_event event;
+       xmlNodePtr node;
+
+       LTTNG_ASSERT(events_node);
+       LTTNG_ASSERT(handle);
+       LTTNG_ASSERT(channel_name);
+
+       for (node = xmlFirstElementChild(events_node); node;
+               node = xmlNextElementSibling(node)) {
+               ret = process_event_node(node, handle, channel_name, CREATION);
+               if (ret) {
+                       goto end;
+               }
+       }
+
+       /*
+        * Disable all events to enable only the necessary events.
+        * Limitations regarding lttng_disable_events and tuple descriptor
+        * force this approach.
+        */
+       memset(&event, 0, sizeof(event));
+       event.loglevel = -1;
+       event.type = LTTNG_EVENT_ALL;
+       ret = lttng_disable_event_ext(handle, &event, channel_name, NULL);
+       if (ret) {
+               goto end;
+       }
+
+       for (node = xmlFirstElementChild(events_node); node;
+                       node = xmlNextElementSibling(node)) {
+               ret = process_event_node(node, handle, channel_name, ENABLE);
+               if (ret) {
+                       goto end;
+               }
+       }
+
+end:
+       return ret;
+}
+
+static
+int process_channel_attr_node(xmlNodePtr attr_node,
+               struct lttng_channel *channel, xmlNodePtr *contexts_node,
+               xmlNodePtr *events_node)
+{
+       int ret;
+
+       LTTNG_ASSERT(attr_node);
+       LTTNG_ASSERT(channel);
+       LTTNG_ASSERT(contexts_node);
+       LTTNG_ASSERT(events_node);
+
+       if (!strcmp((const char *) attr_node->name, config_element_name)) {
+               xmlChar *content;
+
+               /* name */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = lttng_strncpy(channel->name,
+                               (const char *) content,
+                               LTTNG_SYMBOL_NAME_LEN);
+               if (ret == -1) {
+                       WARN("Channel \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
+                                       (const char *) content,
+                                       strlen((const char *) content),
+                                       LTTNG_SYMBOL_NAME_LEN);
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       free(content);
+                       goto end;
+               }
+               free(content);
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_enabled)) {
+               xmlChar *content;
+               int enabled;
+
+               /* enabled */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_bool(content, &enabled);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->enabled = enabled;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_overwrite_mode)) {
+               xmlChar *content;
+
+               /* overwrite_mode */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = get_overwrite_mode(content);
+               free(content);
+               if (ret < 0) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->attr.overwrite = ret;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_subbuf_size)) {
+               xmlChar *content;
+
+               /* subbuffer_size */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &channel->attr.subbuf_size);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_num_subbuf)) {
+               xmlChar *content;
+
+               /* subbuffer_count */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &channel->attr.num_subbuf);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_switch_timer_interval)) {
+               xmlChar *content;
+               uint64_t switch_timer_interval = 0;
+
+               /* switch_timer_interval */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &switch_timer_interval);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               if (switch_timer_interval > UINT_MAX) {
+                       WARN("switch_timer_interval out of range.");
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->attr.switch_timer_interval =
+                       switch_timer_interval;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_read_timer_interval)) {
+               xmlChar *content;
+               uint64_t read_timer_interval = 0;
+
+               /* read_timer_interval */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &read_timer_interval);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               if (read_timer_interval > UINT_MAX) {
+                       WARN("read_timer_interval out of range.");
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->attr.read_timer_interval =
+                       read_timer_interval;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_output_type)) {
+               xmlChar *content;
+
+               /* output_type */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = get_output_type(content);
+               free(content);
+               if (ret < 0) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->attr.output = (lttng_event_output) ret;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_tracefile_size)) {
+               xmlChar *content;
+
+               /* tracefile_size */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &channel->attr.tracefile_size);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_tracefile_count)) {
+               xmlChar *content;
+
+               /* tracefile_count */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &channel->attr.tracefile_count);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_live_timer_interval)) {
+               xmlChar *content;
+               uint64_t live_timer_interval = 0;
+
+               /* live_timer_interval */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &live_timer_interval);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               if (live_timer_interval > UINT_MAX) {
+                       WARN("live_timer_interval out of range.");
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               channel->attr.live_timer_interval =
+                       live_timer_interval;
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_monitor_timer_interval)) {
+               xmlChar *content;
+               uint64_t monitor_timer_interval = 0;
+
+               /* monitor_timer_interval */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_uint(content, &monitor_timer_interval);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               ret = lttng_channel_set_monitor_timer_interval(channel,
+                       monitor_timer_interval);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_blocking_timeout)) {
+               xmlChar *content;
+               int64_t blocking_timeout = 0;
+
+               /* blocking_timeout */
+               content = xmlNodeGetContent(attr_node);
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = parse_int(content, &blocking_timeout);
+               free(content);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               ret = lttng_channel_set_blocking_timeout(channel,
+                       blocking_timeout);
+               if (ret) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+       } else if (!strcmp((const char *) attr_node->name,
+                       config_element_events)) {
+               /* events */
+               *events_node = attr_node;
+       } else {
+               /* contexts */
+               *contexts_node = attr_node;
+       }
+       ret = 0;
+end:
+       return ret;
+}
+
+static
+int process_context_node(xmlNodePtr context_node,
+       struct lttng_handle *handle, const char *channel_name)
+{
+       int ret;
+       struct lttng_event_context context;
+       xmlNodePtr context_child_node = xmlFirstElementChild(context_node);
+
+       LTTNG_ASSERT(handle);
+       LTTNG_ASSERT(channel_name);
+
+       if (!context_child_node) {
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       memset(&context, 0, sizeof(context));
+
+       if (!strcmp((const char *) context_child_node->name,
+               config_element_type)) {
+               /* type */
+               xmlChar *content = xmlNodeGetContent(context_child_node);
+
+               if (!content) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = get_context_type(content);
+               free(content);
+               if (ret < 0) {
+                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                       goto end;
+               }
+
+               context.ctx = (lttng_event_context_type) ret;
+       } else if (!strcmp((const char *) context_child_node->name,
+               config_element_context_perf)) {
+               /* perf */
+               xmlNodePtr perf_attr_node;
+
+               context.ctx = handle->domain.type == LTTNG_DOMAIN_KERNEL ?
+                       LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER :
+                       LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER;
+               for (perf_attr_node = xmlFirstElementChild(context_child_node);
+                       perf_attr_node; perf_attr_node =
+                               xmlNextElementSibling(perf_attr_node)) {
+                       if (!strcmp((const char *) perf_attr_node->name,
+                               config_element_type)) {
+                               xmlChar *content;
+                               uint64_t type = 0;
+
+                               /* type */
+                               content = xmlNodeGetContent(perf_attr_node);
+                               if (!content) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+
+                               ret = parse_uint(content, &type);
+                               free(content);
+                               if (ret) {
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               if (type > UINT32_MAX) {
+                                       WARN("perf context type out of range.");
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               context.u.perf_counter.type = type;
+                       } else if (!strcmp((const char *) perf_attr_node->name,
+                               config_element_config)) {
+                               xmlChar *content;
+                               uint64_t config = 0;
+
+                               /* config */
+                               content = xmlNodeGetContent(perf_attr_node);
+                               if (!content) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+
+                               ret = parse_uint(content, &config);
+                               free(content);
+                               if (ret) {
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               context.u.perf_counter.config = config;
+                       } else if (!strcmp((const char *) perf_attr_node->name,
+                               config_element_name)) {
+                               xmlChar *content;
+
+                               /* name */
+                               content = xmlNodeGetContent(perf_attr_node);
+                               if (!content) {
+                                       ret = -LTTNG_ERR_NOMEM;
+                                       goto end;
+                               }
+
+                               ret = lttng_strncpy(context.u.perf_counter.name,
+                                               (const char *) content,
+                                               LTTNG_SYMBOL_NAME_LEN);
+                               if (ret == -1) {
+                                       WARN("Perf counter \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
+                                                       (const char *) content,
+                                                       strlen((const char *) content),
+                                                       LTTNG_SYMBOL_NAME_LEN);
+                                       ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       free(content);
+                                       goto end;
+                               }
+                               free(content);
+                       }
+               }
+       } else if (!strcmp((const char *) context_child_node->name,
+               config_element_context_app)) {
+               /* application context */
+               xmlNodePtr app_ctx_node;
+
+               context.ctx = LTTNG_EVENT_CONTEXT_APP_CONTEXT;
+               for (app_ctx_node = xmlFirstElementChild(context_child_node);
+                               app_ctx_node; app_ctx_node =
+                               xmlNextElementSibling(app_ctx_node)) {
+                       xmlChar *content;
+                       char **target = strcmp(
+                               (const char *) app_ctx_node->name,
+                               config_element_context_app_provider_name) == 0 ?
+                                       &context.u.app_ctx.provider_name :
+                                       &context.u.app_ctx.ctx_name;
+
+                       content = xmlNodeGetContent(app_ctx_node);
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       *target = (char *) content;
+               }
+       } else {
+               /* Unrecognized context type */
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       ret = lttng_add_context(handle, &context, NULL, channel_name);
+       if (context.ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
+               free(context.u.app_ctx.provider_name);
+               free(context.u.app_ctx.ctx_name);
+       }
+end:
+       return ret;
+}
+
+static
+int process_contexts_node(xmlNodePtr contexts_node,
+       struct lttng_handle *handle, const char *channel_name)
+{
+       int ret = 0;
+       xmlNodePtr context_node;
+
+       for (context_node = xmlFirstElementChild(contexts_node); context_node;
+                       context_node = xmlNextElementSibling(context_node)) {
+               ret = process_context_node(context_node, handle, channel_name);
+               if (ret) {
+                       goto end;
+               }
+       }
+end:
+       return ret;
+}
+
+static int get_tracker_elements(enum lttng_process_attr process_attr,
+               const char **element_id_tracker,
+               const char **element_value_type,
+               const char **element_value,
+               const char **element_value_alias,
+               const char **element_name)
+{
+       int ret = 0;
+
+       switch (process_attr) {
+       case LTTNG_PROCESS_ATTR_PROCESS_ID:
+               *element_id_tracker = config_element_process_attr_tracker_pid;
+               *element_value_type = config_element_process_attr_pid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = config_element_process_attr_id;
+               *element_name = NULL;
+               break;
+       case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+               *element_id_tracker = config_element_process_attr_tracker_vpid;
+               *element_value_type = config_element_process_attr_vpid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = NULL;
+               *element_name = NULL;
+               break;
+       case LTTNG_PROCESS_ATTR_USER_ID:
+               *element_id_tracker = config_element_process_attr_tracker_uid;
+               *element_value_type = config_element_process_attr_uid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = NULL;
+               *element_name = config_element_name;
+               break;
+       case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+               *element_id_tracker = config_element_process_attr_tracker_vuid;
+               *element_value_type = config_element_process_attr_vuid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = NULL;
+               *element_name = config_element_name;
+               break;
+       case LTTNG_PROCESS_ATTR_GROUP_ID:
+               *element_id_tracker = config_element_process_attr_tracker_gid;
+               *element_value_type = config_element_process_attr_gid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = NULL;
+               *element_name = config_element_name;
+               break;
+       case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+               *element_id_tracker = config_element_process_attr_tracker_vgid;
+               *element_value_type = config_element_process_attr_vgid_value;
+               *element_value = config_element_process_attr_id;
+               *element_value_alias = NULL;
+               *element_name = config_element_name;
+               break;
+       default:
+               ret = LTTNG_ERR_INVALID;
+       }
+       return ret;
+}
+
+static int process_legacy_pid_tracker_node(
+               xmlNodePtr trackers_node, struct lttng_handle *handle)
+{
+       int ret = 0, child_count;
+       xmlNodePtr targets_node = NULL;
+       xmlNodePtr node;
+       const char *element_id_tracker;
+       const char *element_target_id;
+       const char *element_id;
+       const char *element_id_alias;
+       const char *element_name;
+       enum lttng_error_code tracker_handle_ret_code;
+       struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
+       enum lttng_process_attr_tracker_handle_status status;
+       const enum lttng_process_attr process_attr =
+                       handle->domain.type == LTTNG_DOMAIN_UST ?
+                                       LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID :
+                                       LTTNG_PROCESS_ATTR_PROCESS_ID;
+
+       LTTNG_ASSERT(handle);
+
+       tracker_handle_ret_code = lttng_session_get_tracker_handle(
+                       handle->session_name, handle->domain.type,
+                       process_attr,
+                       &tracker_handle);
+       if (tracker_handle_ret_code != LTTNG_OK) {
+               ret = LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       ret = get_tracker_elements(process_attr, &element_id_tracker,
+                       &element_target_id, &element_id, &element_id_alias,
+                       &element_name);
+       if (ret) {
+               goto end;
+       }
+
+       /* Get the targets node */
+       for (node = xmlFirstElementChild(trackers_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                               config_element_tracker_targets_legacy)) {
+                       targets_node = node;
+                       break;
+               }
+       }
+
+       if (!targets_node) {
+               ret = LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       /* Go through all id target node */
+       child_count = xmlChildElementCount(targets_node);
+       status = lttng_process_attr_tracker_handle_set_tracking_policy(
+                       tracker_handle,
+                       child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
+                                          LTTNG_TRACKING_POLICY_INCLUDE_SET);
+       if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
+               ret = LTTNG_ERR_UNK;
+               goto end;
+       }
+
+       /* Add all tracked values. */
+       for (node = xmlFirstElementChild(targets_node); node;
+                       node = xmlNextElementSibling(node)) {
+               xmlNodePtr pid_target_node = node;
+
+               /* get pid_target node and track it */
+               for (node = xmlFirstElementChild(pid_target_node); node;
+                               node = xmlNextElementSibling(node)) {
+                       if (!strcmp((const char *) node->name,
+                                           config_element_tracker_pid_legacy)) {
+                               int64_t id;
+                               xmlChar *content = xmlNodeGetContent(node);
+
+                               if (!content) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               ret = parse_int(content, &id);
+                               free(content);
+                               if (ret) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               switch (process_attr) {
+                               case LTTNG_PROCESS_ATTR_PROCESS_ID:
+                                       status = lttng_process_attr_process_id_tracker_handle_add_pid(
+                                                       tracker_handle,
+                                                       (pid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+                                       status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
+                                                       tracker_handle,
+                                                       (pid_t) id);
+                                       break;
+                               default:
+                                       ret = LTTNG_ERR_INVALID;
+                                       goto end;
+                               }
+                       }
+                       switch (status) {
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
+                               continue;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
+                               ret = LTTNG_ERR_INVALID;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
+                               ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
+                               ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
+                       default:
+                               ret = LTTNG_ERR_UNK;
+                               goto end;
+                       }
+               }
+               node = pid_target_node;
+       }
+
+end:
+       lttng_process_attr_tracker_handle_destroy(tracker_handle);
+       return ret;
+ }
+
+static int process_id_tracker_node(xmlNodePtr id_tracker_node,
+               struct lttng_handle *handle,
+               enum lttng_process_attr process_attr)
+{
+       int ret = 0, child_count;
+       xmlNodePtr values_node = NULL;
+       xmlNodePtr node;
+       const char *element_id_tracker;
+       const char *element_target_id;
+       const char *element_id;
+       const char *element_id_alias;
+       const char *element_name;
+       enum lttng_error_code tracker_handle_ret_code;
+       struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
+       enum lttng_process_attr_tracker_handle_status status;
+
+       LTTNG_ASSERT(handle);
+       LTTNG_ASSERT(id_tracker_node);
+
+       tracker_handle_ret_code = lttng_session_get_tracker_handle(
+                       handle->session_name, handle->domain.type, process_attr,
+                       &tracker_handle);
+       if (tracker_handle_ret_code != LTTNG_OK) {
+               ret = LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       ret = get_tracker_elements(process_attr, &element_id_tracker,
+                       &element_target_id, &element_id, &element_id_alias,
+                       &element_name);
+       if (ret) {
+               goto end;
+       }
+
+       /* get the values node */
+       for (node = xmlFirstElementChild(id_tracker_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                               config_element_process_attr_values)) {
+                       values_node = node;
+                       break;
+               }
+       }
+
+       if (!values_node) {
+               ret = LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       /* Go through all id target node */
+       child_count = xmlChildElementCount(values_node);
+       status = lttng_process_attr_tracker_handle_set_tracking_policy(
+                       tracker_handle,
+                       child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
+                                          LTTNG_TRACKING_POLICY_INCLUDE_SET);
+       if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
+               ret = LTTNG_ERR_UNK;
+               goto end;
+       }
+
+       /* Add all tracked values. */
+       for (node = xmlFirstElementChild(values_node); node;
+                       node = xmlNextElementSibling(node)) {
+               xmlNodePtr id_target_node = node;
+
+               /* get id node and track it */
+               for (node = xmlFirstElementChild(id_target_node); node;
+                               node = xmlNextElementSibling(node)) {
+                       if (!strcmp((const char *) node->name, element_id) ||
+                                       (element_id_alias &&
+                                                       !strcmp((const char *) node->name,
+                                                                       element_id_alias))) {
+                               int64_t id;
+                               xmlChar *content = xmlNodeGetContent(node);
+
+                               if (!content) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               ret = parse_int(content, &id);
+                               free(content);
+                               if (ret) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               switch (process_attr) {
+                               case LTTNG_PROCESS_ATTR_PROCESS_ID:
+                                       status = lttng_process_attr_process_id_tracker_handle_add_pid(
+                                                       tracker_handle,
+                                                       (pid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+                                       status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
+                                                       tracker_handle,
+                                                       (pid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_USER_ID:
+                                       status = lttng_process_attr_user_id_tracker_handle_add_uid(
+                                                       tracker_handle,
+                                                       (uid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+                                       status = lttng_process_attr_virtual_user_id_tracker_handle_add_uid(
+                                                       tracker_handle,
+                                                       (uid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_GROUP_ID:
+                                       status = lttng_process_attr_group_id_tracker_handle_add_gid(
+                                                       tracker_handle,
+                                                       (gid_t) id);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+                                       status = lttng_process_attr_virtual_group_id_tracker_handle_add_gid(
+                                                       tracker_handle,
+                                                       (gid_t) id);
+                                       break;
+                               default:
+                                       ret = LTTNG_ERR_INVALID;
+                                       goto end;
+                               }
+                       } else if (element_name &&
+                                       !strcmp((const char *) node->name,
+                                                       element_name)) {
+                               xmlChar *content = xmlNodeGetContent(node);
+
+                               if (!content) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               switch (process_attr) {
+                               case LTTNG_PROCESS_ATTR_USER_ID:
+                                       status = lttng_process_attr_user_id_tracker_handle_add_user_name(
+                                                       tracker_handle,
+                                                       (const char *) content);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+                                       status = lttng_process_attr_virtual_user_id_tracker_handle_add_user_name(
+                                                       tracker_handle,
+                                                       (const char *) content);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_GROUP_ID:
+                                       status = lttng_process_attr_group_id_tracker_handle_add_group_name(
+                                                       tracker_handle,
+                                                       (const char *) content);
+                                       break;
+                               case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+                                       status = lttng_process_attr_virtual_group_id_tracker_handle_add_group_name(
+                                                       tracker_handle,
+                                                       (const char *) content);
+                                       break;
+                               default:
+                                       free(content);
+                                       ret = LTTNG_ERR_INVALID;
+                                       goto end;
+                               }
+                               free(content);
+                       }
+                       switch (status) {
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
+                               continue;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
+                               ret = LTTNG_ERR_INVALID;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
+                               ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
+                               ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
+                               break;
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
+                       case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
+                       default:
+                               ret = LTTNG_ERR_UNK;
+                               goto end;
+                       }
+               }
+               node = id_target_node;
+       }
+
+end:
+       lttng_process_attr_tracker_handle_destroy(tracker_handle);
+       return ret;
+}
+
+static
+int process_domain_node(xmlNodePtr domain_node, const char *session_name)
+{
+       int ret;
+       struct lttng_domain domain {};
+       struct lttng_handle *handle = NULL;
+       struct lttng_channel *channel = NULL;
+       xmlNodePtr channels_node = NULL;
+       xmlNodePtr trackers_node = NULL;
+       xmlNodePtr pid_tracker_node = NULL;
+       xmlNodePtr vpid_tracker_node = NULL;
+       xmlNodePtr uid_tracker_node = NULL;
+       xmlNodePtr vuid_tracker_node = NULL;
+       xmlNodePtr gid_tracker_node = NULL;
+       xmlNodePtr vgid_tracker_node = NULL;
+       xmlNodePtr node;
+
+       LTTNG_ASSERT(session_name);
+
+       ret = init_domain(domain_node, &domain);
+       if (ret) {
+               goto end;
+       }
+
+       handle = lttng_create_handle(session_name, &domain);
+       if (!handle) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       /* get the channels node */
+       for (node = xmlFirstElementChild(domain_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                       config_element_channels)) {
+                       channels_node = node;
+                       break;
+               }
+       }
+
+       if (!channels_node) {
+               goto end;
+       }
+
+       /* create all channels */
+       for (node = xmlFirstElementChild(channels_node); node;
+               node = xmlNextElementSibling(node)) {
+               const enum lttng_domain_type original_domain = domain.type;
+               xmlNodePtr contexts_node = NULL;
+               xmlNodePtr events_node = NULL;
+               xmlNodePtr channel_attr_node;
+
+               /*
+                * Channels of the "agent" types cannot be created directly.
+                * They are meant to be created implicitly through the
+                * activation of events in their domain. However, a user
+                * can override the default channel configuration attributes
+                * by creating the underlying UST channel _before_ enabling
+                * an agent domain event.
+                *
+                * Hence, the channel's type is substituted before the creation
+                * and restored by the time the events are created.
+                */
+               switch (domain.type) {
+               case LTTNG_DOMAIN_JUL:
+               case LTTNG_DOMAIN_LOG4J:
+               case LTTNG_DOMAIN_PYTHON:
+                       domain.type = LTTNG_DOMAIN_UST;
+               default:
+                       break;
+               }
+
+               channel = lttng_channel_create(&domain);
+               if (!channel) {
+                       ret = -1;
+                       goto end;
+               }
+
+               for (channel_attr_node = xmlFirstElementChild(node);
+                       channel_attr_node; channel_attr_node =
+                       xmlNextElementSibling(channel_attr_node)) {
+                       ret = process_channel_attr_node(channel_attr_node,
+                               channel, &contexts_node, &events_node);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+
+               ret = lttng_enable_channel(handle, channel);
+               if (ret < 0) {
+                       goto end;
+               }
+
+               /* Restore the original channel domain. */
+               domain.type = original_domain;
+
+               ret = process_events_node(events_node, handle, channel->name);
+               if (ret) {
+                       goto end;
+               }
+
+               ret = process_contexts_node(contexts_node, handle,
+                       channel->name);
+               if (ret) {
+                       goto end;
+               }
+
+               lttng_channel_destroy(channel);
+       }
+       channel = NULL;
+
+       /* get the trackers node */
+       for (node = xmlFirstElementChild(domain_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_trackers) ||
+                               !strcmp((const char *) node->name,
+                                               config_element_trackers_legacy)) {
+                       if (trackers_node) {
+                               ERR("Only one instance of `%s` or `%s` is allowed in a session configuration",
+                                               config_element_process_attr_trackers,
+                                               config_element_trackers_legacy);
+                               ret = -1;
+                               goto end;
+                       }
+                       trackers_node = node;
+                       break;
+               }
+       }
+
+       if (!trackers_node) {
+               goto end;
+       }
+
+       for (node = xmlFirstElementChild(trackers_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_pid)) {
+                       pid_tracker_node = node;
+                       ret = process_id_tracker_node(pid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_PROCESS_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_vpid)) {
+                       vpid_tracker_node = node;
+                       ret = process_id_tracker_node(vpid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_uid)) {
+                       uid_tracker_node = node;
+                       ret = process_id_tracker_node(uid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_USER_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_vuid)) {
+                       vuid_tracker_node = node;
+                       ret = process_id_tracker_node(vuid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_gid)) {
+                       gid_tracker_node = node;
+                       ret = process_id_tracker_node(gid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_GROUP_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_process_attr_tracker_vgid)) {
+                       vgid_tracker_node = node;
+                       ret = process_id_tracker_node(vgid_tracker_node, handle,
+                                       LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+               if (!strcmp((const char *) node->name,
+                                   config_element_pid_tracker_legacy)) {
+                       ret = process_legacy_pid_tracker_node(node, handle);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+       }
+
+end:
+       lttng_channel_destroy(channel);
+       lttng_destroy_handle(handle);
+       return ret;
+}
+
+static
+int add_periodic_rotation(const char *name, uint64_t time_us)
+{
+       int ret;
+       enum lttng_rotation_status status;
+       struct lttng_rotation_schedule *periodic =
+                       lttng_rotation_schedule_periodic_create();
+
+       if (!periodic) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto error;
+       }
+
+       status = lttng_rotation_schedule_periodic_set_period(periodic,
+                       time_us);
+       if (status != LTTNG_ROTATION_STATUS_OK) {
+               ret = -LTTNG_ERR_INVALID;
+               goto error;
+       }
+
+       status = lttng_session_add_rotation_schedule(name, periodic);
+       switch (status) {
+       case LTTNG_ROTATION_STATUS_OK:
+               ret = 0;
+               break;
+       case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
+       case LTTNG_ROTATION_STATUS_INVALID:
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               break;
+       default:
+               ret = -LTTNG_ERR_UNK;
+               break;
+       }
+error:
+       lttng_rotation_schedule_destroy(periodic);
+       return ret;
+}
+
+static
+int add_size_rotation(const char *name, uint64_t size_bytes)
+{
+       int ret;
+       enum lttng_rotation_status status;
+       struct lttng_rotation_schedule *size =
+                       lttng_rotation_schedule_size_threshold_create();
+
+       if (!size) {
+               ret = -LTTNG_ERR_NOMEM;
+               goto error;
+       }
+
+       status = lttng_rotation_schedule_size_threshold_set_threshold(size,
+                       size_bytes);
+       if (status != LTTNG_ROTATION_STATUS_OK) {
+               ret = -LTTNG_ERR_INVALID;
+               goto error;
+       }
+
+       status = lttng_session_add_rotation_schedule(name, size);
+       switch (status) {
+       case LTTNG_ROTATION_STATUS_OK:
+               ret = 0;
+               break;
+       case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
+       case LTTNG_ROTATION_STATUS_INVALID:
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               break;
+       default:
+               ret = -LTTNG_ERR_UNK;
+               break;
+       }
+error:
+       lttng_rotation_schedule_destroy(size);
+       return ret;
+}
+
+static
+int process_session_rotation_schedules_node(
+               xmlNodePtr schedules_node,
+               uint64_t *rotation_timer_interval,
+               uint64_t *rotation_size)
+{
+       int ret = 0;
+       xmlNodePtr child;
+
+       for (child = xmlFirstElementChild(schedules_node);
+                       child;
+                       child = xmlNextElementSibling(child)) {
+               if (!strcmp((const char *) child->name,
+                               config_element_rotation_schedule_periodic)) {
+                       xmlChar *content;
+                       xmlNodePtr time_us_node;
+
+                       /* periodic rotation schedule */
+                       time_us_node = xmlFirstElementChild(child);
+                       if (!time_us_node ||
+                                       strcmp((const char *) time_us_node->name,
+                                               config_element_rotation_schedule_periodic_time_us)) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       /* time_us child */
+                       content = xmlNodeGetContent(time_us_node);
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+                       ret = parse_uint(content, rotation_timer_interval);
+                       free(content);
+                       if (ret) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+               } else if (!strcmp((const char *) child->name,
+                               config_element_rotation_schedule_size_threshold)) {
+                       xmlChar *content;
+                       xmlNodePtr bytes_node;
+
+                       /* size_threshold rotation schedule */
+                       bytes_node = xmlFirstElementChild(child);
+                       if (!bytes_node ||
+                                       strcmp((const char *) bytes_node->name,
+                                               config_element_rotation_schedule_size_threshold_bytes)) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+
+                       /* bytes child */
+                       content = xmlNodeGetContent(bytes_node);
+                       if (!content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+                       ret = parse_uint(content, rotation_size);
+                       free(content);
+                       if (ret) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto end;
+                       }
+               }
+       }
+
+end:
+       return ret;
+}
+
+static
+int process_session_node(xmlNodePtr session_node, const char *session_name,
+               int overwrite,
+               const struct config_load_session_override_attr *overrides)
+{
+       int ret, started = -1, snapshot_mode = -1;
+       uint64_t live_timer_interval = UINT64_MAX,
+                        rotation_timer_interval = 0,
+                        rotation_size = 0;
+       xmlChar *name = NULL;
+       xmlChar *shm_path = NULL;
+       xmlNodePtr domains_node = NULL;
+       xmlNodePtr output_node = NULL;
+       xmlNodePtr node;
+       xmlNodePtr attributes_child;
+       struct lttng_domain *kernel_domain = NULL;
+       struct lttng_domain *ust_domain = NULL;
+       struct lttng_domain *jul_domain = NULL;
+       struct lttng_domain *log4j_domain = NULL;
+       struct lttng_domain *python_domain = NULL;
+
+       for (node = xmlFirstElementChild(session_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!name && !strcmp((const char *) node->name,
+                       config_element_name)) {
+                       /* name */
+                       xmlChar *node_content = xmlNodeGetContent(node);
+                       if (!node_content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto error;
+                       }
+
+                       name = node_content;
+               } else if (!domains_node && !strcmp((const char *) node->name,
+                       config_element_domains)) {
+                       /* domains */
+                       domains_node = node;
+               } else if (started == -1 && !strcmp((const char *) node->name,
+                       config_element_started)) {
+                       /* started */
+                       xmlChar *node_content = xmlNodeGetContent(node);
+                       if (!node_content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto error;
+                       }
+
+                       ret = parse_bool(node_content, &started);
+                       free(node_content);
+                       if (ret) {
+                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                               goto error;
+                       }
+               } else if (!output_node && !strcmp((const char *) node->name,
+                       config_element_output)) {
+                       /* output */
+                       output_node = node;
+               } else if (!shm_path && !strcmp((const char *) node->name,
+                       config_element_shared_memory_path)) {
+                       /* shared memory path */
+                       xmlChar *node_content = xmlNodeGetContent(node);
+                       if (!node_content) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto error;
+                       }
+
+                       shm_path = node_content;
+               } else {
+                       /*
+                        * attributes, snapshot_mode, live_timer_interval, rotation_size,
+                        * rotation_timer_interval.
+                        */
+                       for (attributes_child = xmlFirstElementChild(node); attributes_child;
+                                       attributes_child = xmlNextElementSibling(attributes_child)) {
+                               if (!strcmp((const char *) attributes_child->name,
+                                                       config_element_snapshot_mode)) {
+                                       /* snapshot_mode */
+                                       xmlChar *snapshot_mode_content =
+                                               xmlNodeGetContent(attributes_child);
+                                       if (!snapshot_mode_content) {
+                                               ret = -LTTNG_ERR_NOMEM;
+                                               goto error;
+                                       }
+
+                                       ret = parse_bool(snapshot_mode_content, &snapshot_mode);
+                                       free(snapshot_mode_content);
+                                       if (ret) {
+                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                               goto error;
+                                       }
+                               } else if (!strcmp((const char *) attributes_child->name,
+                                                       config_element_live_timer_interval)) {
+                                       /* live_timer_interval */
+                                       xmlChar *timer_interval_content =
+                                               xmlNodeGetContent(attributes_child);
+                                       if (!timer_interval_content) {
+                                               ret = -LTTNG_ERR_NOMEM;
+                                               goto error;
+                                       }
+
+                                       ret = parse_uint(timer_interval_content, &live_timer_interval);
+                                       free(timer_interval_content);
+                                       if (ret) {
+                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                               goto error;
+                                       }
+                               } else if (!strcmp((const char *) attributes_child->name,
+                                                       config_element_rotation_schedules)) {
+                                       ret = process_session_rotation_schedules_node(
+                                                       attributes_child,
+                                                       &rotation_timer_interval,
+                                                       &rotation_size);
+                                       if (ret) {
+                                               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                               goto error;
+                                       }
+
+                               }
+                       }
+               }
+       }
+
+       if (!name) {
+               /* Mandatory attribute, as defined in the session XSD */
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto error;
+       }
+
+       if (session_name && strcmp((char *) name, session_name)) {
+               /* This is not the session we are looking for */
+               ret = -LTTNG_ERR_NO_SESSION;
+               goto error;
+       }
+
+       /* Init domains to create the session handles */
+       for (node = xmlFirstElementChild(domains_node); node;
+               node = xmlNextElementSibling(node)) {
+               struct lttng_domain *domain;
+
+               domain = (lttng_domain *) zmalloc(sizeof(*domain));
+               if (!domain) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto error;
+               }
+
+               ret = init_domain(node, domain);
+               if (ret) {
+                       goto domain_init_error;
+               }
+
+               switch (domain->type) {
+               case LTTNG_DOMAIN_KERNEL:
+                       if (kernel_domain) {
+                               /* Same domain seen twice, invalid! */
+                               goto domain_init_error;
+                       }
+                       kernel_domain = domain;
+                       break;
+               case LTTNG_DOMAIN_UST:
+                       if (ust_domain) {
+                               /* Same domain seen twice, invalid! */
+                               goto domain_init_error;
+                       }
+                       ust_domain = domain;
+                       break;
+               case LTTNG_DOMAIN_JUL:
+                       if (jul_domain) {
+                               /* Same domain seen twice, invalid! */
+                               goto domain_init_error;
+                       }
+                       jul_domain = domain;
+                       break;
+               case LTTNG_DOMAIN_LOG4J:
+                       if (log4j_domain) {
+                               /* Same domain seen twice, invalid! */
+                               goto domain_init_error;
+                       }
+                       log4j_domain = domain;
+                       break;
+               case LTTNG_DOMAIN_PYTHON:
+                       if (python_domain) {
+                               /* Same domain seen twice, invalid! */
+                               goto domain_init_error;
+                       }
+                       python_domain = domain;
+                       break;
+               default:
+                       WARN("Invalid domain type");
+                       goto domain_init_error;
+               }
+               continue;
+domain_init_error:
+               free(domain);
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto error;
+       }
+
+       /* Apply overrides */
+       if (overrides) {
+               if (overrides->session_name) {
+                       xmlChar *name_override = xmlStrdup(BAD_CAST(overrides->session_name));
+                       if (!name_override) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto error;
+                       }
+
+                       /* Overrides the session name to the provided name */
+                       xmlFree(name);
+                       name = name_override;
+               }
+       }
+
+       if (overwrite) {
+               /* Destroy session if it exists */
+               ret = lttng_destroy_session((const char *) name);
+               if (ret && ret != -LTTNG_ERR_SESS_NOT_FOUND) {
+                       ERR("Failed to destroy existing session.");
+                       goto error;
+               }
+       }
+
+       /* Create session type depending on output type */
+       if (snapshot_mode && snapshot_mode != -1) {
+               ret = create_snapshot_session((const char *) name, output_node,
+                               overrides);
+       } else if (live_timer_interval &&
+               live_timer_interval != UINT64_MAX) {
+               ret = create_session((const char *) name,
+                               output_node, live_timer_interval, overrides);
+       } else {
+               /* regular session */
+               ret = create_session((const char *) name,
+                               output_node, UINT64_MAX, overrides);
+       }
+       if (ret) {
+               goto error;
+       }
+
+       if (shm_path) {
+               ret = lttng_set_session_shm_path((const char *) name,
+                               (const char *) shm_path);
+               if (ret) {
+                       goto error;
+               }
+       }
+
+       for (node = xmlFirstElementChild(domains_node); node;
+               node = xmlNextElementSibling(node)) {
+               ret = process_domain_node(node, (const char *) name);
+               if (ret) {
+                       goto end;
+               }
+       }
+
+       if (rotation_timer_interval) {
+               ret = add_periodic_rotation((const char *) name,
+                               rotation_timer_interval);
+               if (ret < 0) {
+                       goto error;
+               }
+       }
+       if (rotation_size) {
+               ret = add_size_rotation((const char *) name,
+                               rotation_size);
+               if (ret < 0) {
+                       goto error;
+               }
+       }
+
+       if (started) {
+               ret = lttng_start_tracing((const char *) name);
+               if (ret) {
+                       goto end;
+               }
+       }
+
+end:
+       if (ret < 0) {
+               ERR("Failed to load session %s: %s", (const char *) name,
+                       lttng_strerror(ret));
+               lttng_destroy_session((const char *) name);
+       }
+
+error:
+       free(kernel_domain);
+       free(ust_domain);
+       free(jul_domain);
+       free(log4j_domain);
+       free(python_domain);
+       xmlFree(name);
+       xmlFree(shm_path);
+       return ret;
+}
+
+/*
+ * Return 1 if the given path is readable by the current UID or 0 if not.
+ * Return -1 if the path is EPERM.
+ */
+static int validate_file_read_creds(const char *path)
+{
+       int ret;
+
+       LTTNG_ASSERT(path);
+
+       /* Can we read the file. */
+       ret = access(path, R_OK);
+       if (!ret) {
+               goto valid;
+       }
+       if (errno == EACCES) {
+               return -1;
+       } else {
+               /* Invalid. */
+               return 0;
+       }
+valid:
+       return 1;
+}
+
+static
+int load_session_from_file(const char *path, const char *session_name,
+       struct session_config_validation_ctx *validation_ctx, int overwrite,
+       const struct config_load_session_override_attr *overrides)
+{
+       int ret, session_found = !session_name;
+       xmlDocPtr doc = NULL;
+       xmlNodePtr sessions_node;
+       xmlNodePtr session_node;
+
+       LTTNG_ASSERT(path);
+       LTTNG_ASSERT(validation_ctx);
+
+       ret = validate_file_read_creds(path);
+       if (ret != 1) {
+               if (ret == -1) {
+                       ret = -LTTNG_ERR_EPERM;
+               } else {
+                       ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
+               }
+               goto end;
+       }
+
+       doc = xmlParseFile(path);
+       if (!doc) {
+               ret = -LTTNG_ERR_LOAD_IO_FAIL;
+               goto end;
+       }
+
+       ret = xmlSchemaValidateDoc(validation_ctx->schema_validation_ctx, doc);
+       if (ret) {
+               ERR("Session configuration file validation failed");
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       sessions_node = xmlDocGetRootElement(doc);
+       if (!sessions_node) {
+               ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
+               goto end;
+       }
+
+       for (session_node = xmlFirstElementChild(sessions_node);
+               session_node; session_node =
+                       xmlNextElementSibling(session_node)) {
+               ret = process_session_node(session_node,
+                       session_name, overwrite, overrides);
+               if (!session_name && ret) {
+                       /* Loading error occurred. */
+                       goto end;
+               } else if (session_name) {
+                       if (ret == 0) {
+                               /* Target session found and loaded */
+                               session_found = 1;
+                               break;
+                       } else if (ret == -LTTNG_ERR_NO_SESSION) {
+                               /*
+                                * Ignore this error, we are looking for a
+                                * specific session.
+                                */
+                               ret = 0;
+                       } else {
+                               /* Loading error occurred. */
+                               goto end;
+                       }
+               }
+       }
+end:
+       xmlFreeDoc(doc);
+       if (!ret) {
+               ret = session_found ? 0 : -LTTNG_ERR_LOAD_SESSION_NOENT;
+       }
+       return ret;
+}
+
+static
+int load_session_from_path(const char *path, const char *session_name,
+       struct session_config_validation_ctx *validation_ctx, int overwrite,
+       const struct config_load_session_override_attr *overrides)
+{
+       int ret, session_found = !session_name;
+       DIR *directory = NULL;
+       struct lttng_dynamic_buffer file_path;
+       size_t path_len;
+
+       LTTNG_ASSERT(path);
+       LTTNG_ASSERT(validation_ctx);
+       path_len = strlen(path);
+       lttng_dynamic_buffer_init(&file_path);
+       if (path_len >= LTTNG_PATH_MAX) {
+               ERR("Session configuration load path \"%s\" length (%zu) exceeds the maximal length allowed (%d)",
+                               path, path_len, LTTNG_PATH_MAX);
+               ret = -LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       directory = opendir(path);
+       if (!directory) {
+               switch (errno) {
+               case ENOTDIR:
+                       /* Try the file loading. */
+                       break;
+               case ENOENT:
+                       ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
+                       goto end;
+               default:
+                       ret = -LTTNG_ERR_LOAD_IO_FAIL;
+                       goto end;
+               }
+       }
+       if (directory) {
+               size_t file_path_root_len;
+
+               ret = lttng_dynamic_buffer_set_capacity(&file_path,
+                               LTTNG_PATH_MAX);
+               if (ret) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               ret = lttng_dynamic_buffer_append(&file_path, path, path_len);
+               if (ret) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               if (file_path.data[file_path.size - 1] != '/') {
+                       ret = lttng_dynamic_buffer_append(&file_path, "/", 1);
+                       if (ret) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+               }
+               file_path_root_len = file_path.size;
+
+               /* Search for *.lttng files */
+               for (;;) {
+                       size_t file_name_len;
+                       struct dirent *result;
+
+                       /*
+                        * When the end of the directory stream is reached, NULL
+                        * is returned and errno is kept unchanged. When an
+                        * error occurs, NULL is returned and errno is set
+                        * accordingly. To distinguish between the two, set
+                        * errno to zero before calling readdir().
+                        *
+                        * On success, readdir() returns a pointer to a dirent
+                        * structure. This structure may be statically
+                        * allocated, do not attempt to free(3) it.
+                        */
+                       errno = 0;
+                       result = readdir(directory);
+
+                       /* Reached end of dir stream or error out. */
+                       if (!result) {
+                               if (errno) {
+                                       PERROR("Failed to enumerate the contents of path \"%s\" while loading session, readdir returned", path);
+                                       ret = -LTTNG_ERR_LOAD_IO_FAIL;
+                                       goto end;
+                               }
+                               break;
+                       }
+
+                       file_name_len = strlen(result->d_name);
+
+                       if (file_name_len <=
+                               sizeof(DEFAULT_SESSION_CONFIG_FILE_EXTENSION)) {
+                               continue;
+                       }
+
+                       if (file_path.size + file_name_len >= LTTNG_PATH_MAX) {
+                               WARN("Ignoring file \"%s\" since the path's length (%zu) would exceed the maximal permitted size (%d)",
+                                               result->d_name,
+                                               /* +1 to account for NULL terminator. */
+                                               file_path.size + file_name_len + 1,
+                                               LTTNG_PATH_MAX);
+                               continue;
+                       }
+
+                       /* Does the file end with .lttng? */
+                       if (strcmp(DEFAULT_SESSION_CONFIG_FILE_EXTENSION,
+                                       result->d_name + file_name_len - sizeof(
+                                       DEFAULT_SESSION_CONFIG_FILE_EXTENSION) + 1)) {
+                               continue;
+                       }
+
+                       ret = lttng_dynamic_buffer_append(&file_path, result->d_name,
+                                       file_name_len + 1);
+                       if (ret) {
+                               ret = -LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+
+                       ret = load_session_from_file(file_path.data, session_name,
+                               validation_ctx, overwrite, overrides);
+                       if (session_name &&
+                                       (!ret || ret != -LTTNG_ERR_LOAD_SESSION_NOENT)) {
+                               session_found = 1;
+                               break;
+                       }
+                       if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
+                               goto end;
+                       }
+                       /*
+                        * Reset the buffer's size to the location of the
+                        * path's trailing '/'.
+                        */
+                       ret = lttng_dynamic_buffer_set_size(&file_path,
+                                       file_path_root_len);
+                       if (ret) {
+                               ret = -LTTNG_ERR_UNK;
+                               goto end;
+                       }
+               }
+       } else {
+               ret = load_session_from_file(path, session_name,
+                       validation_ctx, overwrite, overrides);
+               if (ret) {
+                       goto end;
+               }
+               session_found = 1;
+       }
+
+       ret = 0;
+end:
+       if (directory) {
+               if (closedir(directory)) {
+                       PERROR("closedir");
+               }
+       }
+       if (!ret && !session_found) {
+               ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
+       }
+       lttng_dynamic_buffer_reset(&file_path);
+       return ret;
+}
+
+/*
+ * Validate that the given path's credentials and the current process have the
+ * same UID. If so, return 1 else return 0 if it does NOT match.
+ */
+static int validate_path_creds(const char *path)
+{
+       int ret, uid = getuid();
+       struct stat buf;
+
+       LTTNG_ASSERT(path);
+
+       if (uid == 0) {
+               goto valid;
+       }
+
+       ret = stat(path, &buf);
+       if (ret < 0) {
+               if (errno != ENOENT) {
+                       PERROR("stat");
+               }
+               goto valid;
+       }
+
+       if (buf.st_uid != uid) {
+               goto invalid;
+       }
+
+valid:
+       return 1;
+invalid:
+       return 0;
+}
+
+int config_load_session(const char *path, const char *session_name,
+               int overwrite, unsigned int autoload,
+               const struct config_load_session_override_attr *overrides)
+{
+       int ret;
+       bool session_loaded = false;
+       const char *path_ptr = NULL;
+       struct session_config_validation_ctx validation_ctx = { 0 };
+
+       ret = init_session_config_validation_ctx(&validation_ctx);
+       if (ret) {
+               goto end;
+       }
+
+       if (!path) {
+               const char *home_path;
+               const char *sys_path;
+
+               /* Try home path */
+               home_path = utils_get_home_dir();
+               if (home_path) {
+                       char path_buf[PATH_MAX];
+
+                       /*
+                        * Try user session configuration path. Ignore error here so we can
+                        * continue loading the system wide sessions.
+                        */
+                       if (autoload) {
+                               ret = snprintf(path_buf, sizeof(path_buf),
+                                               DEFAULT_SESSION_HOME_CONFIGPATH
+                                               "/" DEFAULT_SESSION_CONFIG_AUTOLOAD,
+                                               home_path);
+                               if (ret < 0) {
+                                       PERROR("snprintf session autoload home config path");
+                                       ret = -LTTNG_ERR_INVALID;
+                                       goto end;
+                               }
+
+                               /*
+                                * Credentials are only validated for the autoload in order to
+                                * avoid any user session daemon to try to load kernel sessions
+                                * automatically and failing all the times.
+                                */
+                               ret = validate_path_creds(path_buf);
+                               if (ret) {
+                                       path_ptr = path_buf;
+                               }
+                       } else {
+                               ret = snprintf(path_buf, sizeof(path_buf),
+                                               DEFAULT_SESSION_HOME_CONFIGPATH,
+                                               home_path);
+                               if (ret < 0) {
+                                       PERROR("snprintf session home config path");
+                                       ret = -LTTNG_ERR_INVALID;
+                                       goto end;
+                               }
+                               path_ptr = path_buf;
+                       }
+                       if (path_ptr) {
+                               ret = load_session_from_path(path_ptr, session_name,
+                                               &validation_ctx, overwrite, overrides);
+                               if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
+                                       goto end;
+                               }
+                               /*
+                                * Continue even if the session was found since we have to try
+                                * the system wide sessions.
+                                */
+                               session_loaded = true;
+                       }
+               }
+
+               /* Reset path pointer for the system wide dir. */
+               path_ptr = NULL;
+
+               /* Try system wide configuration directory. */
+               if (autoload) {
+                       sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH "/"
+                               DEFAULT_SESSION_CONFIG_AUTOLOAD;
+                       ret = validate_path_creds(sys_path);
+                       if (ret) {
+                               path_ptr = sys_path;
+                       }
+               } else {
+                       sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH;
+                       path_ptr = sys_path;
+               }
+
+               if (path_ptr) {
+                       ret = load_session_from_path(path_ptr, session_name,
+                                       &validation_ctx, overwrite, overrides);
+                       if (!ret) {
+                               session_loaded = true;
+                       }
+               } else {
+                       ret = 0;
+               }
+       } else {
+               ret = access(path, F_OK);
+               if (ret < 0) {
+                       PERROR("access");
+                       switch (errno) {
+                       case ENOENT:
+                               ret = -LTTNG_ERR_INVALID;
+                               WARN("Session configuration path does not exist.");
+                               break;
+                       case EACCES:
+                               ret = -LTTNG_ERR_EPERM;
+                               break;
+                       default:
+                               ret = -LTTNG_ERR_UNK;
+                               break;
+                       }
+                       goto end;
+               }
+
+               ret = load_session_from_path(path, session_name,
+                       &validation_ctx, overwrite, overrides);
+       }
+end:
+       fini_session_config_validation_ctx(&validation_ctx);
+       if (ret == -LTTNG_ERR_LOAD_SESSION_NOENT && !session_name && !path) {
+               /*
+                * Don't report an error if no sessions are found when called
+                * without a session_name or a search path.
+                */
+               ret = 0;
+       }
+
+       if (session_loaded && ret == -LTTNG_ERR_LOAD_SESSION_NOENT) {
+               /* A matching session was found in one of the search paths. */
+               ret = 0;
+       }
+       return ret;
+}
+
+static
+void __attribute__((destructor)) session_config_exit(void)
+{
+       xmlCleanupParser();
+}
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