--- /dev/null
+/*
+ * Copyright (C) 2019 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <lttng/constant.h>
+#include <common/string-utils/format.h>
+#include <common/trace-chunk.h>
+#include <common/trace-chunk-registry.h>
+#include <common/hashtable/utils.h>
+#include <common/hashtable/hashtable.h>
+#include <common/error.h>
+#include <common/utils.h>
+#include <common/time.h>
+#include <common/optional.h>
+#include <common/compat/directory-handle.h>
+#include <common/credentials.h>
+#include <common/defaults.h>
+#include <common/dynamic-array.h>
+
+#include <urcu/ref.h>
+#include <urcu/rculfhash.h>
+#include <sys/stat.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stdio.h>
+
+/*
+ * Two ISO 8601-compatible timestamps, separated by a hypen, followed an
+ * index, i.e. <start-iso-8601>-<end-iso-8601>-<id-uint64_t>.
+ */
+#define GENERATED_CHUNK_NAME_LEN (2 * sizeof("YYYYmmddTHHMMSS+HHMM") + MAX_INT_DEC_LEN(uint64_t))
+#define DIR_CREATION_MODE (S_IRWXU | S_IRWXG)
+
+enum trace_chunk_mode {
+ TRACE_CHUNK_MODE_USER,
+ TRACE_CHUNK_MODE_OWNER,
+};
+
+/*
+ * Callback to invoke on release of a trace chunk. Note that there is no
+ * need to 'lock' the trace chunk during the execution of these callbacks
+ * since only one thread may access a chunk during its destruction (the last
+ * to release its reference to the chunk).
+ */
+typedef void (*chunk_close_command)(struct lttng_trace_chunk *trace_chunk);
+
+/* Move a completed trace chunk to the 'completed' trace archive folder. */
+static
+void lttng_trace_chunk_move_to_completed(struct lttng_trace_chunk *trace_chunk);
+
+struct chunk_credentials {
+ bool use_current_user;
+ struct lttng_credentials user;
+};
+
+struct lttng_trace_chunk {
+ pthread_mutex_t lock;
+ struct urcu_ref ref;
+ LTTNG_OPTIONAL(enum trace_chunk_mode) mode;
+ /*
+ * First-level directories created within the trace chunk.
+ * Elements are of type 'char *'.
+ */
+ struct lttng_dynamic_pointer_array top_level_directories;
+ /* Is contained within an lttng_trace_chunk_registry_element? */
+ bool in_registry_element;
+ bool name_overriden;
+ char *name;
+ /* An unset id means the chunk is anonymous. */
+ LTTNG_OPTIONAL(uint64_t) id;
+ LTTNG_OPTIONAL(time_t) timestamp_creation;
+ LTTNG_OPTIONAL(time_t) timestamp_close;
+ LTTNG_OPTIONAL(struct chunk_credentials) credentials;
+ LTTNG_OPTIONAL(struct lttng_directory_handle) session_output_directory;
+ LTTNG_OPTIONAL(struct lttng_directory_handle) chunk_directory;
+ LTTNG_OPTIONAL(enum lttng_trace_chunk_command_type) close_command;
+};
+
+/* A trace chunk is uniquely identified by its (session id, chunk id) tuple. */
+struct lttng_trace_chunk_registry_element {
+ uint64_t session_id;
+ struct lttng_trace_chunk chunk;
+ /* Weak and only set when added. */
+ struct lttng_trace_chunk_registry *registry;
+ struct cds_lfht_node trace_chunk_registry_ht_node;
+ /* call_rcu delayed reclaim. */
+ struct rcu_head rcu_node;
+};
+
+struct lttng_trace_chunk_registry {
+ struct cds_lfht *ht;
+};
+
+const char *close_command_names[] = {
+ [LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED] =
+ "move to completed chunk folder",
+};
+
+chunk_close_command close_command_funcs[] = {
+ [LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED] =
+ lttng_trace_chunk_move_to_completed,
+};
+
+static
+bool lttng_trace_chunk_registry_element_equals(
+ const struct lttng_trace_chunk_registry_element *a,
+ const struct lttng_trace_chunk_registry_element *b)
+{
+ if (a->session_id != b->session_id) {
+ goto not_equal;
+ }
+ if (a->chunk.id.is_set != b->chunk.id.is_set) {
+ goto not_equal;
+ }
+ if (a->chunk.id.is_set && a->chunk.id.value != b->chunk.id.value) {
+ goto not_equal;
+ }
+ return true;
+not_equal:
+ return false;
+}
+
+static
+int lttng_trace_chunk_registry_element_match(struct cds_lfht_node *node,
+ const void *key)
+{
+ const struct lttng_trace_chunk_registry_element *element_a, *element_b;
+
+ element_a = (const struct lttng_trace_chunk_registry_element *) key;
+ element_b = caa_container_of(node, typeof(*element_b),
+ trace_chunk_registry_ht_node);
+ return lttng_trace_chunk_registry_element_equals(element_a, element_b);
+}
+
+static
+unsigned long lttng_trace_chunk_registry_element_hash(
+ const struct lttng_trace_chunk_registry_element *element)
+{
+ unsigned long hash = hash_key_u64(&element->session_id,
+ lttng_ht_seed);
+
+ if (element->chunk.id.is_set) {
+ hash ^= hash_key_u64(&element->chunk.id.value, lttng_ht_seed);
+ }
+
+ return hash;
+}
+
+static
+char *generate_chunk_name(uint64_t chunk_id, time_t creation_timestamp,
+ const time_t *close_timestamp)
+{
+ int ret = 0;
+ char *new_name= NULL;
+ char start_datetime[sizeof("YYYYmmddTHHMMSS+HHMM")] = {};
+ char end_datetime_suffix[sizeof("-YYYYmmddTHHMMSS+HHMM")] = {};
+
+ ret = time_to_iso8601_str(
+ creation_timestamp,
+ start_datetime, sizeof(start_datetime));
+ if (ret) {
+ ERR("Failed to format trace chunk start date time");
+ goto error;
+ }
+ if (close_timestamp) {
+ *end_datetime_suffix = '-';
+ ret = time_to_iso8601_str(
+ *close_timestamp,
+ end_datetime_suffix + 1,
+ sizeof(end_datetime_suffix));
+ if (ret) {
+ ERR("Failed to format trace chunk end date time");
+ goto error;
+ }
+ }
+ new_name = zmalloc(GENERATED_CHUNK_NAME_LEN);
+ if (!new_name) {
+ ERR("Failed to allocate buffer for automatically-generated trace chunk name");
+ goto error;
+ }
+ ret = snprintf(new_name, GENERATED_CHUNK_NAME_LEN, "%s%s-%" PRIu64,
+ start_datetime, end_datetime_suffix, chunk_id);
+ if (ret >= GENERATED_CHUNK_NAME_LEN || ret == -1) {
+ ERR("Failed to format trace chunk name");
+ goto error;
+ }
+
+ return new_name;
+error:
+ free(new_name);
+ return NULL;
+}
+
+static
+void lttng_trace_chunk_init(struct lttng_trace_chunk *chunk)
+{
+ urcu_ref_init(&chunk->ref);
+ pthread_mutex_init(&chunk->lock, NULL);
+ lttng_dynamic_pointer_array_init(&chunk->top_level_directories);
+}
+
+static
+void lttng_trace_chunk_fini(struct lttng_trace_chunk *chunk)
+{
+ if (chunk->session_output_directory.is_set) {
+ lttng_directory_handle_fini(
+ &chunk->session_output_directory.value);
+ }
+ if (chunk->chunk_directory.is_set) {
+ lttng_directory_handle_fini(&chunk->chunk_directory.value);
+ }
+ free(chunk->name);
+ chunk->name = NULL;
+ lttng_dynamic_pointer_array_reset(&chunk->top_level_directories, free);
+ pthread_mutex_destroy(&chunk->lock);
+}
+
+static
+struct lttng_trace_chunk *lttng_trace_chunk_allocate(void)
+{
+ struct lttng_trace_chunk *chunk = NULL;
+
+ chunk = zmalloc(sizeof(*chunk));
+ if (!chunk) {
+ ERR("Failed to allocate trace chunk");
+ goto end;
+ }
+ lttng_trace_chunk_init(chunk);
+end:
+ return chunk;
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk *lttng_trace_chunk_create_anonymous(void)
+{
+ DBG("Creating anonymous trace chunk");
+ return lttng_trace_chunk_allocate();
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk *lttng_trace_chunk_create(
+ uint64_t chunk_id, time_t chunk_creation_time)
+{
+ struct lttng_trace_chunk *chunk;
+ char chunk_creation_datetime_buf[16] = {};
+ const char *chunk_creation_datetime_str = "(formatting error)";
+ struct tm timeinfo_buf, *timeinfo;
+
+ timeinfo = localtime_r(&chunk_creation_time, &timeinfo_buf);
+ if (timeinfo) {
+ size_t strftime_ret;
+
+ /* Don't fail because of this; it is only used for logging. */
+ strftime_ret = strftime(chunk_creation_datetime_buf,
+ sizeof(chunk_creation_datetime_buf),
+ "%Y%m%d-%H%M%S", timeinfo);
+ if (strftime_ret) {
+ chunk_creation_datetime_str =
+ chunk_creation_datetime_buf;
+ }
+ }
+
+ DBG("Creating trace chunk: chunk_id = %" PRIu64 ", creation time = %s",
+ chunk_id, chunk_creation_datetime_str);
+ chunk = lttng_trace_chunk_allocate();
+ if (!chunk) {
+ goto end;
+ }
+
+ LTTNG_OPTIONAL_SET(&chunk->id, chunk_id);
+ LTTNG_OPTIONAL_SET(&chunk->timestamp_creation, chunk_creation_time);
+ if (chunk_id != 0) {
+ chunk->name = generate_chunk_name(chunk_id,
+ chunk_creation_time, NULL);
+ if (!chunk->name) {
+ ERR("Failed to allocate trace chunk name storage");
+ goto error;
+ }
+ }
+
+ DBG("Chunk name set to \"%s\"", chunk->name ? : "(none)");
+end:
+ return chunk;
+error:
+ lttng_trace_chunk_put(chunk);
+ return NULL;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_id(
+ struct lttng_trace_chunk *chunk, uint64_t *id)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->id.is_set) {
+ *id = chunk->id.value;
+ } else {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ }
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_creation_timestamp(
+ struct lttng_trace_chunk *chunk, time_t *creation_ts)
+
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->timestamp_creation.is_set) {
+ *creation_ts = chunk->timestamp_creation.value;
+ } else {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ }
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_close_timestamp(
+ struct lttng_trace_chunk *chunk, time_t *close_ts)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->timestamp_close.is_set) {
+ *close_ts = chunk->timestamp_close.value;
+ } else {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ }
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_close_timestamp(
+ struct lttng_trace_chunk *chunk, time_t close_ts)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->timestamp_creation.is_set) {
+ ERR("Failed to set trace chunk close timestamp: creation timestamp is unset");
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION;
+ goto end;
+ }
+ if (chunk->timestamp_creation.value > close_ts) {
+ ERR("Failed to set trace chunk close timestamp: close timestamp is before creation timestamp");
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT;
+ goto end;
+ }
+ LTTNG_OPTIONAL_SET(&chunk->timestamp_close, close_ts);
+ free(chunk->name);
+ chunk->name = generate_chunk_name(LTTNG_OPTIONAL_GET(chunk->id),
+ LTTNG_OPTIONAL_GET(chunk->timestamp_creation),
+ &close_ts);
+ if (!chunk->name) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ }
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_name(
+ struct lttng_trace_chunk *chunk, const char **name,
+ bool *name_overriden)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (name_overriden) {
+ *name_overriden = chunk->name_overriden;
+ }
+ if (!chunk->name) {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ goto end;
+ }
+ *name = chunk->name;
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_override_name(
+ struct lttng_trace_chunk *chunk, const char *name)
+
+{
+ char *new_name;
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ if (!name || !*name || strnlen(name, LTTNG_NAME_MAX) == LTTNG_NAME_MAX) {
+ ERR("Attempted to set an invalid name on a trace chunk: name = %s",
+ name ? : "NULL");
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT;
+ goto end;
+ }
+
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->id.is_set) {
+ ERR("Attempted to set an override name on an anonymous trace chunk: name = %s",
+ name);
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION;
+ goto end_unlock;
+ }
+ new_name = strdup(name);
+ if (!new_name) {
+ ERR("Failed to allocate new trace chunk name");
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end_unlock;
+ }
+ free(chunk->name);
+ chunk->name = new_name;
+ chunk->name_overriden = true;
+end_unlock:
+ pthread_mutex_unlock(&chunk->lock);
+end:
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_credentials(
+ struct lttng_trace_chunk *chunk,
+ struct lttng_credentials *credentials)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->credentials.is_set) {
+ if (chunk->credentials.value.use_current_user) {
+ credentials->uid = geteuid();
+ credentials->gid = getegid();
+ } else {
+ *credentials = chunk->credentials.value.user;
+ }
+ } else {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ }
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials(
+ struct lttng_trace_chunk *chunk,
+ const struct lttng_credentials *user_credentials)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+ const struct chunk_credentials credentials = {
+ .user = *user_credentials,
+ .use_current_user = false,
+ };
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->credentials.is_set) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ LTTNG_OPTIONAL_SET(&chunk->credentials, credentials);
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials_current_user(
+ struct lttng_trace_chunk *chunk)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+ const struct chunk_credentials credentials = {
+ .use_current_user = true,
+ };
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->credentials.is_set) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ LTTNG_OPTIONAL_SET(&chunk->credentials, credentials);
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_as_owner(
+ struct lttng_trace_chunk *chunk,
+ struct lttng_directory_handle *session_output_directory)
+{
+ int ret;
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+ struct lttng_directory_handle chunk_directory_handle;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->mode.is_set) {
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION;
+ goto end;
+ }
+ if (!chunk->credentials.is_set) {
+ /*
+ * Fatal error, credentials must be set before a
+ * directory is created.
+ */
+ ERR("Credentials of trace chunk are unset: refusing to set session output directory");
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+
+ if (chunk->name) {
+ /*
+ * A nameless chunk does not need its own output directory.
+ * The session's output directory will be used.
+ */
+ ret = lttng_directory_handle_create_subdirectory_as_user(
+ session_output_directory,
+ chunk->name,
+ DIR_CREATION_MODE,
+ !chunk->credentials.value.use_current_user ?
+ &chunk->credentials.value.user : NULL);
+ if (ret) {
+ PERROR("Failed to create chunk output directory \"%s\"",
+ chunk->name);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ }
+ ret = lttng_directory_handle_init_from_handle(&chunk_directory_handle,
+ chunk->name,
+ session_output_directory);
+ if (ret) {
+ /* The function already logs on all error paths. */
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ LTTNG_OPTIONAL_SET(&chunk->session_output_directory,
+ lttng_directory_handle_move(session_output_directory));
+ LTTNG_OPTIONAL_SET(&chunk->chunk_directory,
+ lttng_directory_handle_move(&chunk_directory_handle));
+ LTTNG_OPTIONAL_SET(&chunk->mode, TRACE_CHUNK_MODE_OWNER);
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_as_user(
+ struct lttng_trace_chunk *chunk,
+ struct lttng_directory_handle *chunk_directory)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->mode.is_set) {
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION;
+ goto end;
+ }
+ if (!chunk->credentials.is_set) {
+ ERR("Credentials of trace chunk are unset: refusing to set chunk output directory");
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ LTTNG_OPTIONAL_SET(&chunk->chunk_directory,
+ lttng_directory_handle_move(chunk_directory));
+ LTTNG_OPTIONAL_SET(&chunk->mode, TRACE_CHUNK_MODE_USER);
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_get_chunk_directory_handle(
+ struct lttng_trace_chunk *chunk,
+ const struct lttng_directory_handle **handle)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->chunk_directory.is_set) {
+ status = LTTNG_TRACE_CHUNK_STATUS_NONE;
+ goto end;
+ }
+
+ *handle = &chunk->chunk_directory.value;
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+/* Add a top-level directory to the trace chunk if it was previously unknown. */
+static
+int add_top_level_directory_unique(struct lttng_trace_chunk *chunk,
+ const char *new_path)
+{
+ int ret = 0;
+ bool found = false;
+ size_t i, count = lttng_dynamic_pointer_array_get_count(
+ &chunk->top_level_directories);
+ const char *new_path_separator_pos = strchr(new_path, '/');
+ const ptrdiff_t new_path_top_level_len = new_path_separator_pos ?
+ new_path_separator_pos - new_path : strlen(new_path);
+
+ for (i = 0; i < count; i++) {
+ const char *path = lttng_dynamic_pointer_array_get_pointer(
+ &chunk->top_level_directories, i);
+ const ptrdiff_t path_top_level_len = strlen(path);
+
+ if (path_top_level_len != new_path_top_level_len) {
+ continue;
+ }
+ if (!strncmp(path, new_path, path_top_level_len)) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ char *copy = strndup(new_path, new_path_top_level_len);
+
+ DBG("Adding new top-level directory \"%s\" to trace chunk \"%s\"",
+ new_path, chunk->name ? : "(unnamed)");
+ if (!copy) {
+ PERROR("Failed to copy path");
+ ret = -1;
+ goto end;
+ }
+ ret = lttng_dynamic_pointer_array_add_pointer(
+ &chunk->top_level_directories, copy);
+ if (ret) {
+ ERR("Allocation failure while adding top-level directory entry to a trace chunk");
+ free(copy);
+ goto end;
+ }
+ }
+end:
+ return ret;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_create_subdirectory(
+ struct lttng_trace_chunk *chunk,
+ const char *path)
+{
+ int ret;
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ DBG("Creating trace chunk subdirectory \"%s\"", path);
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->credentials.is_set) {
+ /*
+ * Fatal error, credentials must be set before a
+ * directory is created.
+ */
+ ERR("Credentials of trace chunk are unset: refusing to create subdirectory \"%s\"",
+ path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ if (!chunk->mode.is_set ||
+ chunk->mode.value != TRACE_CHUNK_MODE_OWNER) {
+ ERR("Attempted to create trace chunk subdirectory \"%s\" through a non-owner chunk",
+ path);
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION;
+ goto end;
+ }
+ if (!chunk->chunk_directory.is_set) {
+ ERR("Attempted to create trace chunk subdirectory \"%s\" before setting the chunk output directory",
+ path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ if (*path == '/') {
+ ERR("Refusing to create absolute trace chunk directory \"%s\"",
+ path);
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT;
+ goto end;
+ }
+ ret = lttng_directory_handle_create_subdirectory_recursive_as_user(
+ &chunk->chunk_directory.value, path,
+ DIR_CREATION_MODE,
+ chunk->credentials.value.use_current_user ?
+ NULL : &chunk->credentials.value.user);
+ if (ret) {
+ PERROR("Failed to create trace chunk subdirectory \"%s\"",
+ path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ ret = add_top_level_directory_unique(chunk, path);
+ if (ret) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_open_file(
+ struct lttng_trace_chunk *chunk, const char *file_path,
+ int flags, mode_t mode, int *out_fd)
+{
+ int ret;
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ DBG("Opening trace chunk file \"%s\"", file_path);
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->credentials.is_set) {
+ /*
+ * Fatal error, credentials must be set before a
+ * file is created.
+ */
+ ERR("Credentials of trace chunk are unset: refusing to open file \"%s\"",
+ file_path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ if (!chunk->chunk_directory.is_set) {
+ ERR("Attempted to open trace chunk file \"%s\" before setting the chunk output directory",
+ file_path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ ret = lttng_directory_handle_open_file_as_user(
+ &chunk->chunk_directory.value, file_path, flags, mode,
+ chunk->credentials.value.use_current_user ?
+ NULL : &chunk->credentials.value.user);
+ if (ret < 0) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ *out_fd = ret;
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+LTTNG_HIDDEN
+int lttng_trace_chunk_unlink_file(struct lttng_trace_chunk *chunk,
+ const char *file_path)
+{
+ int ret;
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ DBG("Unlinking trace chunk file \"%s\"", file_path);
+ pthread_mutex_lock(&chunk->lock);
+ if (!chunk->credentials.is_set) {
+ /*
+ * Fatal error, credentials must be set before a
+ * directory is created.
+ */
+ ERR("Credentials of trace chunk are unset: refusing to unlink file \"%s\"",
+ file_path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ if (!chunk->chunk_directory.is_set) {
+ ERR("Attempted to unlink trace chunk file \"%s\" before setting the chunk output directory",
+ file_path);
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+ ret = lttng_directory_handle_unlink_file_as_user(
+ &chunk->chunk_directory.value, file_path,
+ chunk->credentials.value.use_current_user ?
+ NULL : &chunk->credentials.value.user);
+ if (ret < 0) {
+ status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
+ goto end;
+ }
+end:
+ pthread_mutex_unlock(&chunk->lock);
+ return status;
+}
+
+static
+void lttng_trace_chunk_move_to_completed(struct lttng_trace_chunk *trace_chunk)
+{
+ int ret;
+ char *directory_to_rename = NULL;
+ bool free_directory_to_rename = false;
+ const int session_dirfd =
+ trace_chunk->session_output_directory.value.dirfd;
+ char *archived_chunk_name = NULL;
+ const uint64_t chunk_id = LTTNG_OPTIONAL_GET(trace_chunk->id);
+ const time_t creation_timestamp =
+ LTTNG_OPTIONAL_GET(trace_chunk->timestamp_creation);
+ const time_t close_timestamp =
+ LTTNG_OPTIONAL_GET(trace_chunk->timestamp_close);
+ LTTNG_OPTIONAL(struct lttng_directory_handle) archived_chunks_directory;
+
+ assert(trace_chunk->mode.is_set);
+ assert(trace_chunk->mode.value == TRACE_CHUNK_MODE_OWNER);
+ assert(!trace_chunk->name_overriden);
+
+ /*
+ * The fist trace chunk of a session is directly output to the
+ * session's output folder. In this case, the top level directories
+ * must be moved to a temporary folder before that temporary directory
+ * is renamed to match the chunk's name.
+ */
+ if (chunk_id == 0) {
+ struct lttng_directory_handle temporary_rename_directory;
+ size_t i, count = lttng_dynamic_pointer_array_get_count(
+ &trace_chunk->top_level_directories);
+
+ ret = lttng_directory_handle_create_subdirectory_as_user(
+ &trace_chunk->session_output_directory.value,
+ DEFAULT_TEMPORARY_CHUNK_RENAME_DIRECTORY,
+ DIR_CREATION_MODE,
+ !trace_chunk->credentials.value.use_current_user ?
+ &trace_chunk->credentials.value.user : NULL);
+ if (ret) {
+ PERROR("Failed to create temporary trace chunk rename directory \"%s\"",
+ DEFAULT_TEMPORARY_CHUNK_RENAME_DIRECTORY);
+ }
+
+ ret = lttng_directory_handle_init_from_handle(&temporary_rename_directory,
+ DEFAULT_TEMPORARY_CHUNK_RENAME_DIRECTORY,
+ &trace_chunk->session_output_directory.value);
+ if (ret) {
+ ERR("Failed to get handle to temporary trace chunk rename directory");
+ goto end;
+ }
+
+ for (i = 0; i < count; i++) {
+ const int temp_dirfd = temporary_rename_directory.dirfd;
+ const char *top_level_name =
+ lttng_dynamic_pointer_array_get_pointer(
+ &trace_chunk->top_level_directories, i);
+
+ /*
+ * FIXME replace renamat() use by directory handle
+ * wrapper for non-POSIX 2008 systems.
+ */
+ ret = renameat(session_dirfd, top_level_name,
+ temp_dirfd, top_level_name);
+ if (ret) {
+ PERROR("Failed to move \"%s\" to temporary trace chunk rename directory",
+ top_level_name);
+ lttng_directory_handle_fini(
+ &temporary_rename_directory);
+ goto end;
+ }
+ }
+ lttng_directory_handle_fini(&temporary_rename_directory);
+ directory_to_rename = DEFAULT_TEMPORARY_CHUNK_RENAME_DIRECTORY;
+ free_directory_to_rename = false;
+ } else {
+ directory_to_rename = generate_chunk_name(chunk_id,
+ creation_timestamp, NULL);
+ if (!directory_to_rename) {
+ ERR("Failed to generate initial trace chunk name while renaming trace chunk");
+ }
+ free_directory_to_rename = true;
+ }
+
+ archived_chunk_name = generate_chunk_name(chunk_id, creation_timestamp,
+ &close_timestamp);
+ if (!archived_chunk_name) {
+ ERR("Failed to generate archived trace chunk name while renaming trace chunk");
+ goto end;
+ }
+
+ ret = lttng_directory_handle_create_subdirectory_as_user(
+ &trace_chunk->session_output_directory.value,
+ DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY,
+ DIR_CREATION_MODE,
+ !trace_chunk->credentials.value.use_current_user ?
+ &trace_chunk->credentials.value.user :
+ NULL);
+ if (ret) {
+ PERROR("Failed to create \"" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY
+ "\" directory for archived trace chunks");
+ goto end;
+ }
+
+ ret = lttng_directory_handle_init_from_handle(
+ &archived_chunks_directory.value,
+ DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY,
+ &trace_chunk->session_output_directory.value);
+ if (ret) {
+ PERROR("Failed to get handle to archived trace chunks directory");
+ goto end;
+ }
+ archived_chunks_directory.is_set = true;
+
+ /*
+ * FIXME replace renamat() use by directory handle
+ * wrapper for non-POSIX 2008 systems.
+ */
+ ret = renameat(session_dirfd, directory_to_rename,
+ archived_chunks_directory.value.dirfd,
+ archived_chunk_name);
+ if (ret) {
+ PERROR("Failed to rename folder \"%s\" to \"%s\"",
+ directory_to_rename, archived_chunk_name);
+ }
+
+end:
+ if (archived_chunks_directory.is_set) {
+ lttng_directory_handle_fini(&archived_chunks_directory.value);
+ }
+ free(archived_chunk_name);
+ if (free_directory_to_rename) {
+ free(directory_to_rename);
+ }
+}
+
+LTTNG_HIDDEN
+enum lttng_trace_chunk_status lttng_trace_chunk_set_close_command(
+ struct lttng_trace_chunk *chunk,
+ enum lttng_trace_chunk_command_type close_command)
+{
+ enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
+
+ if (close_command < LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED ||
+ close_command >= LTTNG_TRACE_CHUNK_COMMAND_TYPE_MAX) {
+ status = LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT;
+ goto end_unlock;
+ }
+
+ pthread_mutex_lock(&chunk->lock);
+ if (chunk->close_command.is_set) {
+ DBG("Overriding trace chunk close command from \"%s\" to \"%s\"",
+ close_command_names[chunk->close_command.value],
+ close_command_names[close_command]);
+ } else {
+ DBG("Setting trace chunk close command to \"%s\"",
+ close_command_names[close_command]);
+ }
+ LTTNG_OPTIONAL_SET(&chunk->close_command, close_command);
+ pthread_mutex_unlock(&chunk->lock);
+end_unlock:
+ return status;
+}
+
+LTTNG_HIDDEN
+bool lttng_trace_chunk_get(struct lttng_trace_chunk *chunk)
+{
+ return urcu_ref_get_unless_zero(&chunk->ref);
+}
+
+static
+void free_lttng_trace_chunk_registry_element(struct rcu_head *node)
+{
+ struct lttng_trace_chunk_registry_element *element =
+ container_of(node, typeof(*element), rcu_node);
+
+ lttng_trace_chunk_fini(&element->chunk);
+ free(element);
+}
+
+static
+void lttng_trace_chunk_release(struct urcu_ref *ref)
+{
+ struct lttng_trace_chunk *chunk = container_of(ref, typeof(*chunk),
+ ref);
+
+ if (chunk->close_command.is_set) {
+ close_command_funcs[chunk->close_command.value](chunk);
+ }
+
+ if (chunk->in_registry_element) {
+ struct lttng_trace_chunk_registry_element *element;
+
+ element = container_of(chunk, typeof(*element), chunk);
+ if (element->registry) {
+ rcu_read_lock();
+ cds_lfht_del(element->registry->ht,
+ &element->trace_chunk_registry_ht_node);
+ rcu_read_unlock();
+ call_rcu(&element->rcu_node,
+ free_lttng_trace_chunk_registry_element);
+ } else {
+ /* Never published, can be free'd immediately. */
+ free_lttng_trace_chunk_registry_element(
+ &element->rcu_node);
+ }
+ } else {
+ /* Not RCU-protected, free immediately. */
+ lttng_trace_chunk_fini(chunk);
+ free(chunk);
+ }
+}
+
+LTTNG_HIDDEN
+void lttng_trace_chunk_put(struct lttng_trace_chunk *chunk)
+{
+ if (!chunk) {
+ return;
+ }
+ assert(chunk->ref.refcount);
+ urcu_ref_put(&chunk->ref, lttng_trace_chunk_release);
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void)
+{
+ struct lttng_trace_chunk_registry *registry;
+
+ registry = zmalloc(sizeof(*registry));
+ if (!registry) {
+ goto end;
+ }
+
+ registry->ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0,
+ CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+ if (!registry->ht) {
+ goto error;
+ }
+end:
+ return registry;
+error:
+ lttng_trace_chunk_registry_destroy(registry);
+ goto end;
+}
+
+LTTNG_HIDDEN
+void lttng_trace_chunk_registry_destroy(
+ struct lttng_trace_chunk_registry *registry)
+{
+ if (!registry) {
+ return;
+ }
+ if (registry->ht) {
+ int ret = cds_lfht_destroy(registry->ht, NULL);
+ assert(!ret);
+ }
+ free(registry);
+}
+
+static
+struct lttng_trace_chunk_registry_element *
+lttng_trace_chunk_registry_element_create_from_chunk(
+ struct lttng_trace_chunk *chunk, uint64_t session_id)
+{
+ struct lttng_trace_chunk_registry_element *element =
+ zmalloc(sizeof(*element));
+
+ if (!element) {
+ goto end;
+ }
+ cds_lfht_node_init(&element->trace_chunk_registry_ht_node);
+ element->session_id = session_id;
+
+ element->chunk = *chunk;
+ lttng_trace_chunk_init(&element->chunk);
+ if (chunk->session_output_directory.is_set) {
+ element->chunk.session_output_directory.value =
+ lttng_directory_handle_move(
+ &chunk->session_output_directory.value);
+ }
+ if (chunk->chunk_directory.is_set) {
+ element->chunk.chunk_directory.value =
+ lttng_directory_handle_move(
+ &chunk->chunk_directory.value);
+ }
+ /*
+ * The original chunk becomes invalid; the name attribute is transferred
+ * to the new chunk instance.
+ */
+ chunk->name = NULL;
+ element->chunk.in_registry_element = true;
+end:
+ return element;
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk *
+lttng_trace_chunk_registry_publish_chunk(
+ struct lttng_trace_chunk_registry *registry,
+ uint64_t session_id, struct lttng_trace_chunk *chunk)
+{
+ struct lttng_trace_chunk_registry_element *element;
+ unsigned long element_hash;
+
+ pthread_mutex_lock(&chunk->lock);
+ element = lttng_trace_chunk_registry_element_create_from_chunk(chunk,
+ session_id);
+ pthread_mutex_unlock(&chunk->lock);
+ if (!element) {
+ goto end;
+ }
+ /*
+ * chunk is now invalid, the only valid operation is a 'put' from the
+ * caller.
+ */
+ chunk = NULL;
+ element_hash = lttng_trace_chunk_registry_element_hash(element);
+
+ rcu_read_lock();
+ while (1) {
+ struct cds_lfht_node *published_node;
+ struct lttng_trace_chunk *published_chunk;
+ struct lttng_trace_chunk_registry_element *published_element;
+
+ published_node = cds_lfht_add_unique(registry->ht,
+ element_hash,
+ lttng_trace_chunk_registry_element_match,
+ element,
+ &element->trace_chunk_registry_ht_node);
+ if (published_node == &element->trace_chunk_registry_ht_node) {
+ /* Successfully published the new element. */
+ element->registry = registry;
+ /* Acquire a reference for the caller. */
+ if (lttng_trace_chunk_get(&element->chunk)) {
+ break;
+ } else {
+ /*
+ * Another thread concurrently unpublished the
+ * trace chunk. This is currently unexpected.
+ *
+ * Re-attempt to publish.
+ */
+ ERR("Attemp to publish a trace chunk to the chunk registry raced with a trace chunk deletion");
+ continue;
+ }
+ }
+
+ /*
+ * An equivalent trace chunk was published before this trace
+ * chunk. Attempt to acquire a reference to the one that was
+ * already published and release the reference to the copy we
+ * created if successful.
+ */
+ published_element = container_of(published_node,
+ typeof(*published_element),
+ trace_chunk_registry_ht_node);
+ published_chunk = &published_element->chunk;
+ if (lttng_trace_chunk_get(published_chunk)) {
+ lttng_trace_chunk_put(&element->chunk);
+ element = published_element;
+ break;
+ }
+ /*
+ * A reference to the previously published trace chunk could not
+ * be acquired. Hence, retry to publish our copy of the trace
+ * chunk.
+ */
+ }
+ rcu_read_unlock();
+end:
+ return element ? &element->chunk : NULL;
+}
+
+/*
+ * Note that the caller must be registered as an RCU thread.
+ * However, it does not need to hold the RCU read lock. The RCU read lock is
+ * acquired to perform the look-up in the registry's hash table and held until
+ * after a reference to the "found" trace chunk is acquired.
+ *
+ * IOW, holding a reference guarantees the existence of the object for the
+ * caller.
+ */
+static
+struct lttng_trace_chunk *_lttng_trace_chunk_registry_find_chunk(
+ const struct lttng_trace_chunk_registry *registry,
+ uint64_t session_id, uint64_t *chunk_id)
+{
+ const struct lttng_trace_chunk_registry_element target_element = {
+ .chunk.id.is_set = !!chunk_id,
+ .chunk.id.value = chunk_id ? *chunk_id : 0,
+ .session_id = session_id,
+ };
+ const unsigned long element_hash =
+ lttng_trace_chunk_registry_element_hash(
+ &target_element);
+ struct cds_lfht_node *published_node;
+ struct lttng_trace_chunk_registry_element *published_element;
+ struct lttng_trace_chunk *published_chunk = NULL;
+ struct cds_lfht_iter iter;
+
+ rcu_read_lock();
+ cds_lfht_lookup(registry->ht,
+ element_hash,
+ lttng_trace_chunk_registry_element_match,
+ &target_element,
+ &iter);
+ published_node = cds_lfht_iter_get_node(&iter);
+ if (!published_node) {
+ goto end;
+ }
+
+ published_element = container_of(published_node,
+ typeof(*published_element),
+ trace_chunk_registry_ht_node);
+ if (lttng_trace_chunk_get(&published_element->chunk)) {
+ published_chunk = &published_element->chunk;
+ }
+end:
+ rcu_read_unlock();
+ return published_chunk;
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk *
+lttng_trace_chunk_registry_find_chunk(
+ const struct lttng_trace_chunk_registry *registry,
+ uint64_t session_id, uint64_t chunk_id)
+{
+ return _lttng_trace_chunk_registry_find_chunk(registry,
+ session_id, &chunk_id);
+}
+
+LTTNG_HIDDEN
+struct lttng_trace_chunk *
+lttng_trace_chunk_registry_find_anonymous_chunk(
+ const struct lttng_trace_chunk_registry *registry,
+ uint64_t session_id)
+{
+ return _lttng_trace_chunk_registry_find_chunk(registry,
+ session_id, NULL);
+}