start: add lxc_init_handler()

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

src/lxc/criu.c

@@ -797,10 +797,13 @@ static void do_restore(struct lxc_container *c, int status_pipe, struct migrate_
 		close(fd);
 	}
 
-	handler = lxc_init(c->name, c->lxc_conf, c->config_path);
+	handler = lxc_init_handler(c->name, c->lxc_conf, c->config_path);
 	if (!handler)
 		goto out;
 
+	if (lxc_init(c->name, handler) < 0)
+		goto out;
+
 	if (!cgroup_init(handler)) {
 		ERROR("failed initing cgroups");
 		goto out_fini_handler;

src/lxc/execute.c

@@ -111,16 +111,15 @@ static struct lxc_operations execute_start_ops = {
 };
 
 int lxc_execute(const char *name, char *const argv[], int quiet,
-		struct lxc_conf *conf, const char *lxcpath, bool backgrounded)
+		struct lxc_handler *handler, const char *lxcpath,
+		bool backgrounded)
 {
-	struct execute_args args = {
-		.argv = argv,
-		.quiet = quiet
-	};
+	struct execute_args args = {.argv = argv, .quiet = quiet};
 
-	if (lxc_check_inherited(conf, false, -1))
+	if (lxc_check_inherited(handler->conf, false, handler->conf->maincmd_fd))
 		return -1;
 
-	conf->is_execute = 1;
-	return __lxc_start(name, conf, &execute_start_ops, &args, lxcpath, backgrounded);
+	handler->conf->is_execute = 1;
+	return __lxc_start(name, handler, &execute_start_ops, &args, lxcpath,
+			   backgrounded);
 }

src/lxc/lxc.h

@@ -36,6 +36,7 @@ extern "C" {
 struct lxc_msg;
 struct lxc_conf;
 struct lxc_arguments;
+struct lxc_handler;
 
 /**
  Following code is for liblxc.
@@ -51,8 +52,9 @@ struct lxc_arguments;
  * @backgrounded : whether or not the container is daemonized
  * Returns 0 on success, < 0 otherwise
  */
-extern int lxc_start(const char *name, char *const argv[], struct lxc_conf *conf,
-		     const char *lxcpath, bool backgrounded);
+extern int lxc_start(const char *name, char *const argv[],
+		     struct lxc_handler *handler, const char *lxcpath,
+		     bool backgrounded);
 
 /*
  * Start the specified command inside an application container
@@ -64,7 +66,7 @@ extern int lxc_start(const char *name, char *const argv[], struct lxc_conf *conf
  * Returns 0 on success, < 0 otherwise
  */
 extern int lxc_execute(const char *name, char *const argv[], int quiet,
-		       struct lxc_conf *conf, const char *lxcpath,
+		       struct lxc_handler *handler, const char *lxcpath,
 		       bool backgrounded);
 
 /*

src/lxc/lxccontainer.c

@@ -57,6 +57,7 @@
 #include "namespace.h"
 #include "network.h"
 #include "sync.h"
+#include "start.h"
 #include "state.h"
 #include "utils.h"
 #include "version.h"
@@ -715,6 +716,7 @@ static void free_init_cmd(char **argv)
 static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const argv[])
 {
 	int ret;
+	struct lxc_handler *handler;
 	struct lxc_conf *conf;
 	bool daemonize = false;
 	FILE *pid_fp = NULL;
@@ -731,7 +733,7 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 	/* If anything fails before we set error_num, we want an error in there */
 	c->error_num = 1;
 
-	/* container has been setup */
+	/* container has not been setup */
 	if (!c->lxc_conf)
 		return false;
 
@@ -758,8 +760,16 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 	daemonize = c->daemonize;
 	container_mem_unlock(c);
 
+	/* initialize handler */
+	handler = lxc_init_handler(c->name, conf, c->config_path);
+	if (!handler)
+		return false;
+
 	if (useinit) {
-		ret = lxc_execute(c->name, argv, 1, conf, c->config_path, daemonize);
+		TRACE("calling \"lxc_execute\"");
+		ret = lxc_execute(c->name, argv, 1, handler, c->config_path,
+				  daemonize);
+		c->error_num = ret;
 		return ret == 0 ? true : false;
 	}
 
@@ -791,6 +801,7 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 			 * the PID file, child will do the free and unlink.
 			 */
 			c->pidfile = NULL;
+			close(c->lxc_conf->maincmd_fd);
 			return wait_on_daemonized_start(c, pid);
 		}
 
@@ -815,7 +826,7 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 			SYSERROR("Error chdir()ing to /.");
 			exit(1);
 		}
-		lxc_check_inherited(conf, true, -1);
+		lxc_check_inherited(conf, true, handler->conf->maincmd_fd);
 		if (null_stdfds() < 0) {
 			ERROR("failed to close fds");
 			exit(1);
@@ -828,7 +839,7 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 		}
 	}
 
-	/* We need to write PID file after daeminize, so we always
+	/* We need to write PID file after daemonize, so we always
 	 * write the right PID.
 	 */
 	if (c->pidfile) {
@@ -869,13 +880,20 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 	}
 
 reboot:
-	if (lxc_check_inherited(conf, daemonize, -1)) {
+	if (conf->reboot == 2) {
+		/* initialize handler */
+		handler = lxc_init_handler(c->name, conf, c->config_path);
+		if (!handler)
+			goto out;
+	}
+
+	if (lxc_check_inherited(conf, daemonize, handler->conf->maincmd_fd)) {
 		ERROR("Inherited fds found");
 		ret = 1;
 		goto out;
 	}
 
-	ret = lxc_start(c->name, argv, conf, c->config_path, daemonize);
+	ret = lxc_start(c->name, argv, handler, c->config_path, daemonize);
 	c->error_num = ret;
 
 	if (conf->reboot == 1) {
@@ -890,13 +908,11 @@ static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const a
 		free(c->pidfile);
 		c->pidfile = NULL;
 	}
-
 	free_init_cmd(init_cmd);
 
 	if (daemonize)
-		exit (ret == 0 ? true : false);
-	else
-		return (ret == 0 ? true : false);
+		exit(ret == 0 ? true : false);
+	return (ret == 0 ? true : false);
 }
 
 static bool lxcapi_start(struct lxc_container *c, int useinit, char * const argv[])

src/lxc/start.c

@@ -396,14 +396,17 @@ int lxc_poll(const char *name, struct lxc_handler *handler)
 	return -1;
 }
 
-struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char *lxcpath)
+struct lxc_handler *lxc_init_handler(const char *name, struct lxc_conf *conf,
+				     const char *lxcpath)
 {
 	int i;
 	struct lxc_handler *handler;
 
 	handler = malloc(sizeof(*handler));
-	if (!handler)
+	if (!handler) {
+		ERROR("failed to allocate memory");
 		return NULL;
+	}
 
 	memset(handler, 0, sizeof(*handler));
 
@@ -415,16 +418,37 @@ struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char
 	for (i = 0; i < LXC_NS_MAX; i++)
 		handler->nsfd[i] = -1;
 
-	lsm_init();
-
 	handler->name = strdup(name);
 	if (!handler->name) {
-		ERROR("Failed to allocate memory.");
-		goto out_free;
+		ERROR("failed to allocate memory");
+		goto do_partial_cleanup;
 	}
 
-	if (lxc_cmd_init(name, handler, lxcpath))
-		goto out_free_name;
+	if (lxc_cmd_init(name, handler, lxcpath)) {
+		ERROR("failed to set up command socket");
+		goto do_full_cleanup;
+	}
+
+	TRACE("unix domain socket %d for command server is ready",
+	      handler->conf->maincmd_fd);
+
+	return handler;
+
+do_full_cleanup:
+	free(handler->name);
+
+do_partial_cleanup:
+	free(handler);
+
+	return NULL;
+}
+
+int lxc_init(const char *name, struct lxc_handler *handler)
+{
+	struct lxc_conf *conf = handler->conf;
+
+	lsm_init();
+	TRACE("initialized LSM");
 
 	if (lxc_read_seccomp_config(conf) != 0) {
 		ERROR("Failed loading seccomp policy.");
@@ -487,7 +511,7 @@ struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char
 	}
 
 	INFO("Container \"%s\" is initialized.", name);
-	return handler;
+	return 0;
 
 out_restore_sigmask:
 	sigprocmask(SIG_SETMASK, &handler->oldmask, NULL);
@@ -498,12 +522,7 @@ struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char
 out_close_maincmd_fd:
 	close(conf->maincmd_fd);
 	conf->maincmd_fd = -1;
-out_free_name:
-	free(handler->name);
-	handler->name = NULL;
-out_free:
-	free(handler);
-	return NULL;
+	return -1;
 }
 
 void lxc_fini(const char *name, struct lxc_handler *handler)
@@ -1337,17 +1356,16 @@ static int lxc_spawn(struct lxc_handler *handler)
 	return -1;
 }
 
-int __lxc_start(const char *name, struct lxc_conf *conf,
+int __lxc_start(const char *name, struct lxc_handler *handler,
 		struct lxc_operations* ops, void *data, const char *lxcpath,
 		bool backgrounded)
 {
-	struct lxc_handler *handler;
-	int err = -1;
 	int status;
+	int err = -1;
 	bool removed_all_netdevs = true;
+	struct lxc_conf *conf = handler->conf;
 
-	handler = lxc_init(name, conf, lxcpath);
-	if (!handler) {
+	if (lxc_init(name, handler) < 0) {
 		ERROR("Failed to initialize container \"%s\".", name);
 		return -1;
 	}
@@ -1494,15 +1512,15 @@ static struct lxc_operations start_ops = {
 	.post_start = post_start
 };
 
-int lxc_start(const char *name, char *const argv[], struct lxc_conf *conf,
+int lxc_start(const char *name, char *const argv[], struct lxc_handler *handler,
 	      const char *lxcpath, bool backgrounded)
 {
 	struct start_args start_arg = {
 		.argv = argv,
 	};
 
-	conf->need_utmp_watch = 1;
-	return __lxc_start(name, conf, &start_ops, &start_arg, lxcpath, backgrounded);
+	handler->conf->need_utmp_watch = 1;
+	return __lxc_start(name, handler, &start_ops, &start_arg, lxcpath, backgrounded);
 }
 
 static void lxc_destroy_container_on_signal(struct lxc_handler *handler,

src/lxc/start.h

@@ -27,11 +27,11 @@
 #include <sys/param.h>
 #include <stdbool.h>
 
+#include "conf.h"
 #include "config.h"
 #include "state.h"
 #include "namespace.h"
 
-struct lxc_conf;
 
 struct lxc_handler;
 
@@ -66,11 +66,14 @@ struct lxc_handler {
 extern int lxc_poll(const char *name, struct lxc_handler *handler);
 extern int lxc_set_state(const char *name, struct lxc_handler *handler, lxc_state_t state);
 extern void lxc_abort(const char *name, struct lxc_handler *handler);
-extern struct lxc_handler *lxc_init(const char *name, struct lxc_conf *, const char *);
+extern struct lxc_handler *lxc_init_handler(const char *name,
+					    struct lxc_conf *conf,
+					    const char *lxcpath);
+extern int lxc_init(const char *name, struct lxc_handler *handler);
 extern void lxc_fini(const char *name, struct lxc_handler *handler);
 
 extern int lxc_check_inherited(struct lxc_conf *conf, bool closeall, int fd_to_ignore);
-int __lxc_start(const char *, struct lxc_conf *, struct lxc_operations *,
+int __lxc_start(const char *, struct lxc_handler *, struct lxc_operations *,
 		void *, const char *, bool);
 
 extern void resolve_clone_flags(struct lxc_handler *handler);

src/lxc/state.c

@@ -109,24 +109,16 @@ extern int lxc_wait(const char *lxcname, const char *states, int timeout,
 		    const char *lxcpath)
 {
 	struct lxc_msg msg;
-	int state, ret;
-	int s[MAX_STATE] = {0}, fd;
+	int state;
+	int s[MAX_STATE] = {0}, fd = -1, ret = -1;
 
 	if (fillwaitedstates(states, s))
 		return -1;
 
-	if (lxc_monitord_spawn(lxcpath))
-		return -1;
-
-	fd = lxc_monitor_open(lxcpath);
-	if (fd < 0)
-		return -1;
-
 	/*
 	 * if container present,
 	 * then check if already in requested state
 	 */
-	ret = -1;
 	state = lxc_getstate(lxcname, lxcpath);
 	if (state < 0) {
 		goto out_close;
@@ -135,6 +127,13 @@ extern int lxc_wait(const char *lxcname, const char *states, int timeout,
 		goto out_close;
 	}
 
+	if (lxc_monitord_spawn(lxcpath))
+		return -1;
+
+	fd = lxc_monitor_open(lxcpath);
+	if (fd < 0)
+		return -1;
+
 	for (;;) {
 		int64_t elapsed_time, curtime = 0;
 		struct timespec tspec;
@@ -192,6 +191,7 @@ extern int lxc_wait(const char *lxcname, const char *states, int timeout,
 	}
 
 out_close:
-	lxc_monitor_close(fd);
+	if (fd >= 0)
+		lxc_monitor_close(fd);
 	return ret;
 }