#include <urcu.h>
#include <dirent.h>
#include <sys/types.h>
+#include <pthread.h>
#include <common/common.h>
#include <common/sessiond-comm/sessiond-comm.h>
static struct ltt_session_list ltt_session_list = {
.head = CDS_LIST_HEAD_INIT(ltt_session_list.head),
.lock = PTHREAD_MUTEX_INITIALIZER,
+ .removal_cond = PTHREAD_COND_INITIALIZER,
.next_uuid = 0,
};
return <t_session_list;
}
+/*
+ * Returns once the session list is empty.
+ */
+void session_list_wait_empty(void)
+{
+ pthread_mutex_lock(<t_session_list.lock);
+ while (!cds_list_empty(<t_session_list.head)) {
+ pthread_cond_wait(<t_session_list.removal_cond,
+ <t_session_list.lock);
+ }
+ pthread_mutex_unlock(<t_session_list.lock);
+}
+
/*
* Acquire session list lock
*/
consumer_output_put(session->consumer);
snapshot_destroy(&session->snapshot);
- del_session_list(session);
- del_session_ht(session);
+
+ if (session->published) {
+ ASSERT_LOCKED(ltt_session_list.lock);
+ del_session_list(session);
+ del_session_ht(session);
+ pthread_cond_broadcast(<t_session_list.removal_cond);
+ }
free(session);
}
*/
void session_put(struct ltt_session *session)
{
+ if (!session) {
+ return;
+ }
/*
* The session list lock must be held as any session_put()
* may cause the removal of the session from the session_list.
}
/*
- * Create a brand new session and add it to the session list.
+ * Create a new session and add it to the session list.
+ * Session list lock must be held by the caller.
*/
-int session_create(char *name, uid_t uid, gid_t gid)
+enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid,
+ struct ltt_session **out_session)
{
int ret;
- struct ltt_session *new_session;
+ enum lttng_error_code ret_code;
+ struct ltt_session *new_session = NULL;
- /* Allocate session data structure */
+ ASSERT_LOCKED(ltt_session_list.lock);
+ if (name) {
+ struct ltt_session *clashing_session;
+
+ clashing_session = session_find_by_name(name);
+ if (clashing_session) {
+ session_put(clashing_session);
+ ret_code = LTTNG_ERR_EXIST_SESS;
+ goto error;
+ }
+ }
new_session = zmalloc(sizeof(struct ltt_session));
- if (new_session == NULL) {
- PERROR("zmalloc");
- ret = LTTNG_ERR_FATAL;
- goto error_malloc;
+ if (!new_session) {
+ PERROR("Failed to allocate an ltt_session structure");
+ ret_code = LTTNG_ERR_NOMEM;
+ goto error;
}
urcu_ref_init(&new_session->ref);
+ pthread_mutex_init(&new_session->lock, NULL);
- /* Define session name */
- if (name != NULL) {
- if (snprintf(new_session->name, NAME_MAX, "%s", name) < 0) {
- ret = LTTNG_ERR_FATAL;
- goto error_asprintf;
- }
- } else {
- ERR("No session name given");
- ret = LTTNG_ERR_FATAL;
+ new_session->creation_time = time(NULL);
+ if (new_session->creation_time == (time_t) -1) {
+ PERROR("Failed to sample session creation time");
+ ret_code = LTTNG_ERR_SESSION_FAIL;
goto error;
}
- ret = validate_name(name);
- if (ret < 0) {
- ret = LTTNG_ERR_SESSION_INVALID_CHAR;
+ /* Create default consumer output. */
+ new_session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
+ if (new_session->consumer == NULL) {
+ ret_code = LTTNG_ERR_NOMEM;
goto error;
}
+ if (name) {
+ ret = lttng_strncpy(new_session->name, name, sizeof(new_session->name));
+ if (ret) {
+ ret_code = LTTNG_ERR_SESSION_INVALID_CHAR;
+ goto error;
+ }
+ ret = validate_name(name);
+ if (ret < 0) {
+ ret_code = LTTNG_ERR_SESSION_INVALID_CHAR;
+ goto error;
+ }
+ } else {
+ int i = 0;
+ bool found_name = false;
+ char datetime[16];
+ struct tm *timeinfo;
+
+ timeinfo = localtime(&new_session->creation_time);
+ if (!timeinfo) {
+ ret_code = LTTNG_ERR_SESSION_FAIL;
+ goto error;
+ }
+ strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
+ for (i = 0; i < INT_MAX; i++) {
+ struct ltt_session *clashing_session;
+
+ if (i == 0) {
+ ret = snprintf(new_session->name,
+ sizeof(new_session->name),
+ "%s-%s",
+ DEFAULT_SESSION_NAME,
+ datetime);
+ } else {
+ ret = snprintf(new_session->name,
+ sizeof(new_session->name),
+ "%s%d-%s",
+ DEFAULT_SESSION_NAME, i,
+ datetime);
+ }
+ if (ret == -1 || ret >= sizeof(new_session->name)) {
+ /*
+ * Null-terminate in case the name is used
+ * in logging statements.
+ */
+ new_session->name[sizeof(new_session->name) - 1] = '\0';
+ ret_code = LTTNG_ERR_SESSION_FAIL;
+ goto error;
+ }
+
+ clashing_session =
+ session_find_by_name(new_session->name);
+ session_put(clashing_session);
+ if (!clashing_session) {
+ found_name = true;
+ break;
+ }
+ }
+ if (found_name) {
+ DBG("Generated session name \"%s\"", new_session->name);
+ new_session->has_auto_generated_name = true;
+ } else {
+ ERR("Failed to auto-generate a session name");
+ ret_code = LTTNG_ERR_SESSION_FAIL;
+ goto error;
+ }
+ }
+
ret = gethostname(new_session->hostname, sizeof(new_session->hostname));
if (ret < 0) {
if (errno == ENAMETOOLONG) {
new_session->hostname[sizeof(new_session->hostname) - 1] = '\0';
+ ERR("Hostname exceeds the maximal permitted length and has been truncated to %s",
+ new_session->hostname);
} else {
- ret = LTTNG_ERR_FATAL;
+ ret_code = LTTNG_ERR_SESSION_FAIL;
goto error;
}
}
- /* Init kernel session */
- new_session->kernel_session = NULL;
- new_session->ust_session = NULL;
-
- /* Init lock */
- pthread_mutex_init(&new_session->lock, NULL);
-
new_session->uid = uid;
new_session->gid = gid;
ret = snapshot_init(&new_session->snapshot);
if (ret < 0) {
- ret = LTTNG_ERR_NOMEM;
+ ret_code = LTTNG_ERR_NOMEM;
goto error;
}
- new_session->rotation_pending_local = false;
- new_session->rotation_pending_relay = false;
new_session->rotation_state = LTTNG_ROTATION_STATE_NO_ROTATION;
- new_session->rotation_pending_check_timer_enabled = false;
- new_session->rotation_schedule_timer_enabled = false;
-
- /* Add new session to the session list */
- session_lock_list();
+ /* Add new session to the session list. */
new_session->id = add_session_list(new_session);
+
/*
* Add the new session to the ltt_sessions_ht_by_id.
* No ownership is taken by the hash table; it is merely
* by session id.
*/
add_session_ht(new_session);
- session_unlock_list();
+ new_session->published = true;
/*
- * Consumer is let to NULL since the create_session_uri command will set it
- * up and, if valid, assign it to the session.
+ * Consumer is left to NULL since the create_session_uri command will
+ * set it up and, if valid, assign it to the session.
*/
- DBG("Tracing session %s created with ID %" PRIu64 " by UID %d GID %d",
- name, new_session->id, new_session->uid, new_session->gid);
-
- return LTTNG_OK;
-
+ DBG("Tracing session %s created with ID %" PRIu64 " by uid = %d, gid = %d",
+ new_session->name, new_session->id, new_session->uid,
+ new_session->gid);
+ ret_code = LTTNG_OK;
+end:
+ if (new_session) {
+ (void) session_get(new_session);
+ *out_session = new_session;
+ }
+ return ret_code;
error:
-error_asprintf:
- free(new_session);
-
-error_malloc:
- return ret;
+ session_put(new_session);
+ new_session = NULL;
+ goto end;
}
/*
projects / lttng-tools.git / blobdiff