Save/load: pid_tracker feature.

[lttng-tools.git] / src / common / config / config.c

diff --git a/src/common/config/config.c b/src/common/config/config.c
index a4b59ff0865e559e3f2dea86bbc8c3cc022bcec2..03601be486deacc189f260251108534156aa0c1c 100644 (file)
--- a/src/common/config/config.c
+++ b/src/common/config/config.c
@@ -118,6 +118,10 @@ 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_pid_tracker = "pid_tracker";
+const char * const config_element_trackers = "trackers";
+const char * const config_element_targets = "targets";
+const char * const config_element_target_pid = "pid_target";
 
 const char * const config_domain_type_kernel = "KERNEL";
 const char * const config_domain_type_ust = "UST";
@@ -2088,6 +2092,79 @@ end:
        return ret;
 }
 
+static
+int process_pid_tracker_node(xmlNodePtr pid_tracker_node,
+       struct lttng_handle *handle)
+{
+       int ret, child;
+       xmlNodePtr targets_node = NULL;
+       xmlNodePtr node;
+
+       assert(handle);
+       assert(pid_tracker_node);
+       /* get the targets node */
+       for (node = xmlFirstElementChild(pid_tracker_node); node;
+               node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                               config_element_targets)) {
+                       targets_node = node;
+                       break;
+               }
+       }
+
+       if (!targets_node) {
+               ret = LTTNG_ERR_INVALID;
+               goto end;
+       }
+
+       /* Go through all pid_target node */
+       child = xmlChildElementCount(targets_node);
+       if (child == 0) {
+               /* The session is explicitly set to target nothing. */
+               ret = lttng_untrack_pid(handle, -1);
+               if (ret) {
+                       goto end;
+               }
+       }
+       for (node = xmlFirstElementChild(targets_node); node;
+                       node = xmlNextElementSibling(node)) {
+               xmlNodePtr pid_target_node = node;
+
+               /* get pid node and track it */
+               for (node = xmlFirstElementChild(pid_target_node); node;
+                       node = xmlNextElementSibling(node)) {
+                       if (!strcmp((const char *) node->name,
+                                       config_element_pid)) {
+                               int64_t pid;
+                               xmlChar *content = NULL;
+
+                               content = xmlNodeGetContent(node);
+                               if (!content) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               ret = parse_int(content, &pid);
+                               free(content);
+                               if (ret) {
+                                       ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
+                                       goto end;
+                               }
+
+                               ret = lttng_track_pid(handle, (int) pid);
+                               if (ret) {
+                                       goto end;
+                               }
+                       }
+               }
+               node = pid_target_node;
+       }
+
+end:
+       return ret;
+}
+
+
 static
 int process_domain_node(xmlNodePtr domain_node, const char *session_name)
 {
@@ -2095,6 +2172,8 @@ int process_domain_node(xmlNodePtr domain_node, const char *session_name)
        struct lttng_domain domain = { 0 };
        struct lttng_handle *handle = NULL;
        xmlNodePtr channels_node = NULL;
+       xmlNodePtr trackers_node = NULL;
+       xmlNodePtr pid_tracker_node = NULL;
        xmlNodePtr node;
 
        assert(session_name);
@@ -2161,6 +2240,36 @@ int process_domain_node(xmlNodePtr domain_node, const char *session_name)
                        goto end;
                }
        }
+
+       /* get the trackers node */
+       for (node = xmlFirstElementChild(domain_node); node;
+                       node = xmlNextElementSibling(node)) {
+               if (!strcmp((const char *) node->name,
+                                       config_element_trackers)) {
+                       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_pid_tracker)) {
+                       pid_tracker_node = node;
+                       ret = process_pid_tracker_node(pid_tracker_node, handle);
+                       if (ret) {
+                               goto end;
+                       }
+               }
+       }
+
+       if (!pid_tracker_node) {
+               lttng_track_pid(handle, -1);
+       }
+
 end:
        lttng_destroy_handle(handle);
        return ret;
@@ -2495,6 +2604,23 @@ end:
        return ret;
 }
 
+/* Allocate dirent as recommended by READDIR(3), NOTES on readdir_r */
+static
+struct dirent *alloc_dirent(const char *path)
+{
+       size_t len;
+       long name_max;
+       struct dirent *entry;
+
+       name_max = pathconf(path, _PC_NAME_MAX);
+       if (name_max == -1) {
+               name_max = PATH_MAX;
+       }
+       len = offsetof(struct dirent, d_name) + name_max + 1;
+       entry = zmalloc(len);
+       return entry;
+}
+
 static
 int load_session_from_path(const char *path, const char *session_name,
        struct session_config_validation_ctx *validation_ctx, int override)
@@ -2530,7 +2656,7 @@ int load_session_from_path(const char *path, const char *session_name,
                        goto end;
                }
 
-               entry = zmalloc(sizeof(*entry));
+               entry = alloc_dirent(path);
                if (!entry) {
                        ret = -LTTNG_ERR_NOMEM;
                        goto end;