X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=ltt-sessiond%2Fmain.c;h=8a808236878edbefdd468967386e57d6dc2d13f3;hb=508f6562a0a21bebcd6412eb0cf8761d359c3ee4;hp=5e99c7987ce59cb7122e6109d198e35d8399b196;hpb=273ea72ccbbffd1d6b9d5478923d30571d503a6c;p=lttng-tools.git

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index 5e99c7987..8a8082368 100644
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -226,18 +226,18 @@ static int send_unix_sock(int sock, void *buf, size_t len)
  *
  *  Free memory of a command context structure.
  */
-static void clean_command_ctx(struct command_ctx *cmd_ctx)
+static void clean_command_ctx(struct command_ctx **cmd_ctx)
 {
-	DBG("Clean command context structure %p", cmd_ctx);
-	if (cmd_ctx) {
-		if (cmd_ctx->llm) {
-			free(cmd_ctx->llm);
+	DBG("Clean command context structure");
+	if (*cmd_ctx) {
+		if ((*cmd_ctx)->llm) {
+			free((*cmd_ctx)->llm);
 		}
-		if (cmd_ctx->lsm) {
-			free(cmd_ctx->lsm);
+		if ((*cmd_ctx)->lsm) {
+			free((*cmd_ctx)->lsm);
 		}
-		free(cmd_ctx);
-		cmd_ctx = NULL;
+		free(*cmd_ctx);
+		*cmd_ctx = NULL;
 	}
 }
 
@@ -468,7 +468,7 @@ static int update_kernel_pollfd(void)
 	DBG("Updating kernel_pollfd");
 
 	/* Get the number of channel of all kernel session */
-	pthread_mutex_lock(&session_list_ptr->lock);
+	lock_session_list();
 	cds_list_for_each_entry(session, &session_list_ptr->head, list) {
 		lock_session(session);
 		if (session->kernel_session == NULL) {
@@ -505,7 +505,7 @@ static int update_kernel_pollfd(void)
 		}
 		unlock_session(session);
 	}
-	pthread_mutex_unlock(&session_list_ptr->lock);
+	unlock_session_list();
 
 	/* Adding wake up pipe */
 	kernel_pollfd[nb_fd - 2].fd = kernel_poll_pipe[0];
@@ -517,7 +517,7 @@ static int update_kernel_pollfd(void)
 	return nb_fd;
 
 error:
-	pthread_mutex_unlock(&session_list_ptr->lock);
+	unlock_session_list();
 	return -1;
 }
 
@@ -537,7 +537,7 @@ static int update_kernel_stream(int fd)
 
 	DBG("Updating kernel streams for channel fd %d", fd);
 
-	pthread_mutex_lock(&session_list_ptr->lock);
+	lock_session_list();
 	cds_list_for_each_entry(session, &session_list_ptr->head, list) {
 		lock_session(session);
 		if (session->kernel_session == NULL) {
@@ -568,10 +568,10 @@ static int update_kernel_stream(int fd)
 	}
 
 end:
+	unlock_session_list();
 	if (session) {
 		unlock_session(session);
 	}
-	pthread_mutex_unlock(&session_list_ptr->lock);
 	return ret;
 }
 
@@ -1227,6 +1227,30 @@ error:
 	return ret;
 }
 
+/*
+ * Using the session list, filled a lttng_session array to send back to the
+ * client for session listing.
+ *
+ * The session list lock MUST be acquired before calling this function. Use
+ * lock_session_list() and unlock_session_list().
+ */
+static void list_lttng_sessions(struct lttng_session *sessions)
+{
+	int i = 0;
+	struct ltt_session *session;
+
+	DBG("Getting all available session");
+	/*
+	 * Iterate over session list and append data after the control struct in
+	 * the buffer.
+	 */
+	cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+		strncpy(sessions[i].path, session->path, PATH_MAX);
+		strncpy(sessions[i].name, session->name, NAME_MAX);
+		i++;
+	}
+}
+
 /*
  * 	process_client_msg
  *
@@ -1938,20 +1962,23 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
 	*/
 	case LTTNG_LIST_SESSIONS:
 	{
-		unsigned int session_count;
+		lock_session_list();
 
-		session_count = get_session_count();
-		if (session_count == 0) {
+		if (session_list_ptr->count == 0) {
 			ret = LTTCOMM_NO_SESSION;
 			goto error;
 		}
 
-		ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
+		ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
+				session_list_ptr->count);
 		if (ret < 0) {
 			goto setup_error;
 		}
 
-		get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
+		/* Filled the session array */
+		list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
+
+		unlock_session_list();
 
 		ret = LTTCOMM_OK;
 		break;
@@ -2081,7 +2108,7 @@ static void *thread_manage_clients(void *data)
 			/* TODO: Inform client somehow of the fatal error. At this point,
 			 * ret < 0 means that a malloc failed (ENOMEM). */
 			/* Error detected but still accept command */
-			clean_command_ctx(cmd_ctx);
+			clean_command_ctx(&cmd_ctx);
 			continue;
 		}
 
@@ -2092,7 +2119,7 @@ static void *thread_manage_clients(void *data)
 			ERR("Failed to send data back to client");
 		}
 
-		clean_command_ctx(cmd_ctx);
+		clean_command_ctx(&cmd_ctx);
 
 		/* End of transmission */
 		close(sock);
@@ -2109,7 +2136,7 @@ error:
 
 	unlink(client_unix_sock_path);
 
-	clean_command_ctx(cmd_ctx);
+	clean_command_ctx(&cmd_ctx);
 	return NULL;
 }
 
@@ -2495,6 +2522,7 @@ static void set_ulimit(void)
 	int ret;
 	struct rlimit lim;
 
+	/* The kernel does not allowed an infinite limit for open files */
 	lim.rlim_cur = 65535;
 	lim.rlim_max = 65535;
 
@@ -2515,14 +2543,13 @@ int main(int argc, char **argv)
 
 	/* Create thread quit pipe */
 	if (init_thread_quit_pipe() < 0) {
-		/* No goto error because nothing is initialized at this point */
-		exit(EXIT_FAILURE);
+		goto exit;
 	}
 
 	/* Parse arguments */
 	progname = argv[0];
 	if ((ret = parse_args(argc, argv) < 0)) {
-		goto error;
+		goto exit;
 	}
 
 	/* Daemonize */
@@ -2530,7 +2557,7 @@ int main(int argc, char **argv)
 		ret = daemon(0, 0);
 		if (ret < 0) {
 			perror("daemon");
-			goto error;
+			goto exit;
 		}
 	}
 
@@ -2540,7 +2567,7 @@ int main(int argc, char **argv)
 	if (is_root) {
 		ret = create_lttng_rundir();
 		if (ret < 0) {
-			goto error;
+			goto exit;
 		}
 
 		if (strlen(apps_unix_sock_path) == 0) {
@@ -2552,23 +2579,12 @@ int main(int argc, char **argv)
 			snprintf(client_unix_sock_path, PATH_MAX,
 					DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
 		}
-
-		ret = set_kconsumerd_sockets();
-		if (ret < 0) {
-			goto error;
-		}
-
-		/* Setup kernel tracer */
-		init_kernel_tracer();
-
-		/* Set ulimit for open files */
-		set_ulimit();
 	} else {
 		home_path = get_home_dir();
 		if (home_path == NULL) {
 			/* TODO: Add --socket PATH option */
 			ERR("Can't get HOME directory for sockets creation.");
-			goto error;
+			goto exit;
 		}
 
 		if (strlen(apps_unix_sock_path) == 0) {
@@ -2594,10 +2610,31 @@ int main(int argc, char **argv)
 	if ((ret = check_existing_daemon()) == 0) {
 		ERR("Already running daemon.\n");
 		/*
-		 * We do not goto error because we must not
-		 * cleanup() because a daemon is already running.
+		 * We do not goto error because we must not cleanup() because a daemon
+		 * is already running.
 		 */
-		exit(EXIT_FAILURE);
+		goto exit;
+	}
+
+	/* After this point, we can safely call cleanup() so goto error is used */
+
+	/*
+	 * These actions must be executed as root. We do that *after* setting up
+	 * the sockets path because we MUST make the check for another daemon using
+	 * those paths *before* trying to set the kernel consumer sockets and init
+	 * kernel tracer.
+	 */
+	if (is_root) {
+		ret = set_kconsumerd_sockets();
+		if (ret < 0) {
+			goto error;
+		}
+
+		/* Setup kernel tracer */
+		init_kernel_tracer();
+
+		/* Set ulimit for open files */
+		set_ulimit();
 	}
 
 	if (set_signal_handler() < 0) {
@@ -2664,5 +2701,7 @@ int main(int argc, char **argv)
 
 error:
 	cleanup();
+
+exit:
 	exit(EXIT_FAILURE);
 }