Replace strncpy by lttng_strncpy in session config

This eliminates a warning produced by GCC 8 in that repeated
code pattern (potential truncation of the source string) and
using the lttng_strncpy macro reduces code duplication.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/src/common/config/session-config.c b/src/common/config/session-config.c
index 01ae901ad8c35a168611552f4346e1a649bfebe3..a600a5b47fe72b1dcec9f807a73f2ef899ace7df 100644 (file)
--- a/src/common/config/session-config.c
+++ b/src/common/config/session-config.c
@@ -1495,7 +1495,6 @@ int process_probe_attribute_node(xmlNodePtr probe_attribute_node,
        } else if (!strcmp((const char *) probe_attribute_node->name,
                config_element_symbol_name)) {
                xmlChar *content;
-               size_t name_len;
 
                /* symbol_name */
                content = xmlNodeGetContent(probe_attribute_node);
@@ -1504,15 +1503,18 @@ int process_probe_attribute_node(xmlNodePtr probe_attribute_node,
                        goto end;
                }
 
-               name_len = strlen((char *) content);
-               if (name_len >= LTTNG_SYMBOL_NAME_LEN) {
-                       WARN("symbol_name too long.");
+               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;
                }
-
-               strncpy(attr->symbol_name, (const char *) content, name_len);
                free(content);
        }
        ret = 0;
@@ -1561,7 +1563,6 @@ int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
                node = xmlNextElementSibling(node)) {
                if (!strcmp((const char *) node->name, config_element_name)) {
                        xmlChar *content;
-                       size_t name_len;
 
                        /* name */
                        content = xmlNodeGetContent(node);
@@ -1570,15 +1571,18 @@ int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
                                goto end;
                        }
 
-                       name_len = strlen((char *) content);
-                       if (name_len >= LTTNG_SYMBOL_NAME_LEN) {
-                               WARN("Channel name too long.");
+                       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;
                        }
-
-                       strncpy(event.name, (const char *) content, name_len);
                        free(content);
                } else if (!strcmp((const char *) node->name,
                        config_element_enabled)) {
@@ -1769,8 +1773,14 @@ int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
                                        goto end;
                                }
 
-                               strncpy(event.attr.ftrace.symbol_name, (char *) content,
-                                               sym_len);
+                               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);
                        }
                }
@@ -1785,6 +1795,7 @@ int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
                        goto end;
                }
        }
+       ret = 0;
 end:
        for (i = 0; i < exclusion_count; i++) {
                free(exclusions[i]);
@@ -1854,7 +1865,6 @@ int process_channel_attr_node(xmlNodePtr attr_node,
 
        if (!strcmp((const char *) attr_node->name, config_element_name)) {
                xmlChar *content;
-               size_t name_len;
 
                /* name */
                content = xmlNodeGetContent(attr_node);
@@ -1863,15 +1873,18 @@ int process_channel_attr_node(xmlNodePtr attr_node,
                        goto end;
                }
 
-               name_len = strlen((char *) content);
-               if (name_len >= LTTNG_SYMBOL_NAME_LEN) {
-                       WARN("Channel name too long.");
+               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;
                }
-
-               strncpy(channel->name, (const char *) content, name_len);
                free(content);
        } else if (!strcmp((const char *) attr_node->name,
                        config_element_enabled)) {
@@ -2239,7 +2252,6 @@ int process_context_node(xmlNodePtr context_node,
                        } else if (!strcmp((const char *) perf_attr_node->name,
                                config_element_name)) {
                                xmlChar *content;
-                               size_t name_len;
 
                                /* name */
                                content = xmlNodeGetContent(perf_attr_node);
@@ -2248,16 +2260,18 @@ int process_context_node(xmlNodePtr context_node,
                                        goto end;
                                }
 
-                               name_len = strlen((char *) content);
-                               if (name_len >= LTTNG_SYMBOL_NAME_LEN) {
-                                       WARN("perf context name too long.");
+                               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;
                                }
-
-                               strncpy(context.u.perf_counter.name, (const char *) content,
-                                               name_len);
                                free(content);
                        }
                }