Merge pull request #1931 from brauner/2017-11-20/fix_state_socket

src/lxc/commands.c

@@ -229,7 +229,7 @@ static int lxc_cmd_send(const char *name, struct lxc_cmd_rr *cmd,
 	int client_fd;
 	ssize_t ret = -1;
 
-	client_fd = lxc_cmd_connect(name, lxcpath, hashed_sock_name);
+	client_fd = lxc_cmd_connect(name, lxcpath, hashed_sock_name, "command");
 	if (client_fd < 0) {
 		if (client_fd == -ECONNREFUSED)
 			return -ECONNREFUSED;
@@ -1152,11 +1152,32 @@ static int lxc_cmd_process(int fd, struct lxc_cmd_req *req,
 }
 
 static void lxc_cmd_fd_cleanup(int fd, struct lxc_handler *handler,
-			       struct lxc_epoll_descr *descr)
+			       struct lxc_epoll_descr *descr,
+			       const lxc_cmd_t cmd)
 {
+	struct state_client *client;
+	struct lxc_list *cur, *next;
+
 	lxc_console_free(handler->conf, fd);
 	lxc_mainloop_del_handler(descr, fd);
-	close(fd);
+	if (cmd != LXC_CMD_ADD_STATE_CLIENT) {
+		close(fd);
+		return;
+	}
+
+	process_lock();
+	lxc_list_for_each_safe(cur, &handler->state_clients, next) {
+		client = cur->elem;
+		if (client->clientfd != fd)
+			continue;
+
+		/* kick client from list */
+		close(client->clientfd);
+		lxc_list_del(cur);
+		free(cur->elem);
+		free(cur);
+	}
+	process_unlock();
 }
 
 static int lxc_cmd_handler(int fd, uint32_t events, void *data,
@@ -1242,7 +1263,7 @@ out:
 	return ret;
 
 out_close:
-	lxc_cmd_fd_cleanup(fd, handler, descr);
+	lxc_cmd_fd_cleanup(fd, handler, descr, req.cmd);
 	goto out;
 }
 
@@ -1284,8 +1305,7 @@ out_close:
 	goto out;
 }
 
-int lxc_cmd_init(const char *name, struct lxc_handler *handler,
-		 const char *lxcpath)
+int lxc_cmd_init(const char *name, const char *lxcpath, const char *suffix)
 {
 	int fd, len, ret;
 	char path[sizeof(((struct sockaddr_un *)0)->sun_path)] = {0};
@@ -1297,9 +1317,10 @@ int lxc_cmd_init(const char *name, struct lxc_handler *handler,
 	 * because we print the sockname out sometimes.
 	 */
 	len = sizeof(path) - 2;
-	ret = lxc_make_abstract_socket_name(offset, len, name, lxcpath, NULL, "command");
+	ret = lxc_make_abstract_socket_name(offset, len, name, lxcpath, NULL, suffix);
 	if (ret < 0)
 		return -1;
+	TRACE("Creating abstract unix socket \"%s\"", offset);
 
 	fd = lxc_abstract_unix_open(path, SOCK_STREAM, 0);
 	if (fd < 0) {
@@ -1317,8 +1338,7 @@ int lxc_cmd_init(const char *name, struct lxc_handler *handler,
 		return -1;
 	}
 
-	handler->conf->maincmd_fd = fd;
-	return 0;
+	return fd;
 }
 
 int lxc_cmd_mainloop_add(const char *name, struct lxc_epoll_descr *descr,

src/lxc/commands.h

@@ -126,8 +126,7 @@ extern int lxc_cmd_add_state_client(const char *name, const char *lxcpath,
 struct lxc_epoll_descr;
 struct lxc_handler;
 
-extern int lxc_cmd_init(const char *name, struct lxc_handler *handler,
-			    const char *lxcpath);
+extern int lxc_cmd_init(const char *name, const char *lxcpath, const char *suffix);
 extern int lxc_cmd_mainloop_add(const char *name, struct lxc_epoll_descr *descr,
 				    struct lxc_handler *handler);
 extern int lxc_try_cmd(const char *name, const char *lxcpath);

src/lxc/commands_utils.c

@@ -68,16 +68,14 @@ again:
 			goto again;
 		}
 
-		ERROR("failed to receive message: %s", strerror(errno));
+		ERROR("Failed to receive message: %s", strerror(errno));
 		return -1;
 	}
 
-	if (ret == 0) {
-		ERROR("length of message was 0");
+	if (ret < 0)
 		return -1;
-	}
 
-	TRACE("received state %s from state client %d",
+	TRACE("Received state %s from state client %d",
 	      lxc_state2str(msg.value), state_client_fd);
 
 	return msg.value;
@@ -163,7 +161,7 @@ int lxc_make_abstract_socket_name(char *path, int len, const char *lxcname,
 }
 
 int lxc_cmd_connect(const char *name, const char *lxcpath,
-		    const char *hashed_sock_name)
+		    const char *hashed_sock_name, const char *suffix)
 {
 	int ret, client_fd;
 	char path[sizeof(((struct sockaddr_un *)0)->sun_path)] = {0};
@@ -176,7 +174,7 @@ int lxc_cmd_connect(const char *name, const char *lxcpath,
 	 */
 	size_t len = sizeof(path) - 2;
 	ret = lxc_make_abstract_socket_name(offset, len, name, lxcpath,
-					    hashed_sock_name, "command");
+					    hashed_sock_name, suffix);
 	if (ret < 0)
 		return -1;
 

src/lxc/commands_utils.h

@@ -79,6 +79,6 @@ extern int lxc_add_state_client(int state_client_fd,
  *                                     >= 0 client fd
  */
 extern int lxc_cmd_connect(const char *name, const char *lxcpath,
-			   const char *hashed_sock_name);
+			   const char *hashed_sock_name, const char *suffix);
 
 #endif /* __LXC_COMMANDS_UTILS_H */

src/lxc/lxccontainer.c

@@ -801,6 +801,7 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 		NULL,
 	};
 	char **init_cmd = NULL;
+	int keepfds[3] = {-1, -1, -1};
 
 	/* container does exist */
 	if (!c)
@@ -921,11 +922,11 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 			exit(EXIT_FAILURE);
 		}
 
-		ret = lxc_check_inherited(conf, true,
-				          (int[]){handler->conf->maincmd_fd,
-					          handler->state_socket_pair[0],
-					          handler->state_socket_pair[1]},
-				    3);
+		keepfds[0] = handler->conf->maincmd_fd;
+		keepfds[1] = handler->state_socket_pair[0];
+		keepfds[2] = handler->state_socket_pair[1];
+		ret = lxc_check_inherited(conf, true, keepfds,
+					  sizeof(keepfds) / sizeof(keepfds[0]));
 		if (ret < 0)
 			exit(EXIT_FAILURE);
 
@@ -1010,11 +1011,11 @@ reboot:
 		}
 	}
 
-	ret = lxc_check_inherited(conf, daemonize,
-				  (int[]){handler->conf->maincmd_fd,
-					  handler->state_socket_pair[0],
-					  handler->state_socket_pair[1]},
-				  3);
+	keepfds[0] = handler->conf->maincmd_fd;
+	keepfds[1] = handler->state_socket_pair[0];
+	keepfds[2] = handler->state_socket_pair[1];
+	ret = lxc_check_inherited(conf, daemonize, keepfds,
+				  sizeof(keepfds) / sizeof(keepfds[0]));
 	if (ret < 0) {
 		lxc_free_handler(handler);
 		ret = 1;
@@ -1816,7 +1817,7 @@ static bool do_lxcapi_shutdown(struct lxc_container *c, int timeout)
 	if (c->lxc_conf && c->lxc_conf->haltsignal)
 		haltsignal = c->lxc_conf->haltsignal;
 
-	INFO("Using signal number '%d' as halt signal.", haltsignal);
+	INFO("Using signal number '%d' as halt signal", haltsignal);
 
 	/* Add a new state client before sending the shutdown signal so that we
 	 * don't miss a state.
@@ -1827,13 +1828,14 @@ static bool do_lxcapi_shutdown(struct lxc_container *c, int timeout)
 
 	/* Send shutdown signal to container. */
 	if (kill(pid, haltsignal) < 0)
-		WARN("Could not send signal %d to pid %d.", haltsignal, pid);
+		WARN("Could not send signal %d to pid %d", haltsignal, pid);
 
 	/* Retrieve the state. */
 	if (state_client_fd >= 0) {
 		int state;
 		state = lxc_cmd_sock_rcv_state(state_client_fd, timeout);
 		close(state_client_fd);
+		TRACE("Received state \"%s\"", lxc_state2str(state));
 		if (state != STOPPED)
 			return false;
 		retv = true;

src/lxc/start.c

@@ -347,10 +347,10 @@ static int lxc_serve_state_clients(const char *name,
 	*  lxc_cmd_add_state_client() to miss a state.
 	 */
 	handler->state = state;
-	TRACE("set container state to %s", lxc_state2str(state));
+	TRACE("Set container state to %s", lxc_state2str(state));
 
 	if (lxc_list_empty(&handler->state_clients)) {
-		TRACE("no state clients registered");
+		TRACE("No state clients registered");
 		process_unlock();
 		lxc_monitor_send_state(name, state, handler->lxcpath);
 		return 0;
@@ -363,12 +363,12 @@ static int lxc_serve_state_clients(const char *name,
 		client = cur->elem;
 
 		if (!client->states[state]) {
-			TRACE("state %s not registered for state client %d",
+			TRACE("State %s not registered for state client %d",
 			      lxc_state2str(state), client->clientfd);
 			continue;
 		}
 
-		TRACE("sending state %s to state client %d",
+		TRACE("Sending state %s to state client %d",
 		      lxc_state2str(state), client->clientfd);
 
 	again:
@@ -379,7 +379,8 @@ static int lxc_serve_state_clients(const char *name,
 				goto again;
 			}
 
-			ERROR("failed to send message to client");
+			ERROR("%s - Failed to send message to client",
+			      strerror(errno));
 		}
 
 		/* kick client from list */
@@ -553,12 +554,12 @@ struct lxc_handler *lxc_init_handler(const char *name, struct lxc_conf *conf,
 		      handler->state_socket_pair[1]);
 	}
 
-	if (lxc_cmd_init(name, handler, lxcpath)) {
-		ERROR("failed to set up command socket");
+	handler->conf->maincmd_fd = lxc_cmd_init(name, lxcpath, "command");
+	if (handler->conf->maincmd_fd < 0) {
+		ERROR("Failed to set up command socket");
 		goto on_error;
 	}
-
-	TRACE("unix domain socket %d for command server is ready",
+	TRACE("Unix domain socket %d for command server is ready",
 	      handler->conf->maincmd_fd);
 
 	return handler;