lxc_*.c: don't exit with -1

In this patch I tried to stick with each file's coding style, however I
think we should probably change that.  Every main() should always not
return and only exit;  they should always return EXIT_SUCCESS or EXIT_FAILURE
with the only exceptions being cases where we are returning a child's
exit status (lxc_execute, lxc_attach, lxc_init).

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>

doc/lxc-stop.sgml.in

@@ -162,6 +162,41 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   </variablelist>
   </refsect1>
 
+  <refsect1>
+    <title>Exit value</title>
+
+    <variablelist>
+
+      <varlistentry>
+        <term>0</term>
+        <listitem>
+          <para>
+	    The container was successfully stopped.
+          </para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term>1</term>
+        <listitem>
+          <para>
+	    An error occurred while stopping the container.
+          </para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term>2</term>
+        <listitem>
+          <para>
+	    The specified container exists but was not running.
+          </para>
+        </listitem>
+      </varlistentry>
+
+    </variablelist>
+
+  </refsect1>
   <refsect1>
     <title>Diagnostic</title>
 

src/lxc/lxc_attach.c

@@ -195,11 +195,11 @@ int main(int argc, char *argv[])
 
 	ret = lxc_caps_init();
 	if (ret)
-		return ret;
+		return 1;
 
 	ret = lxc_arguments_parse(&my_args, argc, argv);
 	if (ret)
-		return ret;
+		return 1;
 
 	if (!my_args.log_file)
 		my_args.log_file = "none";
@@ -207,7 +207,7 @@ int main(int argc, char *argv[])
 	ret = lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
 			   my_args.progname, my_args.quiet, my_args.lxcpath[0]);
 	if (ret)
-		return ret;
+		return 1;
 	lxc_log_options_no_override();
 
 	if (remount_sys_proc)
@@ -229,14 +229,14 @@ int main(int argc, char *argv[])
 	}
 
 	if (ret < 0)
-		return -1;
+		return 1;
 
 	ret = lxc_wait_for_pid_status(pid);
 	if (ret < 0)
-		return -1;
+		return 1;
 
 	if (WIFEXITED(ret))
 		return WEXITSTATUS(ret);
 
-	return -1;
+	return 1;
 }

src/lxc/lxc_cgroup.c

@@ -68,32 +68,32 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 
 	if (lxc_arguments_parse(&my_args, argc, argv))
-		return -1;
+		return 1;
 
 	if (!my_args.log_file)
 		my_args.log_file = "none";
 
 	if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
 			 my_args.progname, my_args.quiet, my_args.lxcpath[0]))
-		return -1;
+		return 1;
 	lxc_log_options_no_override();
 
 	state_object = my_args.argv[0];
 
 	c = lxc_container_new(my_args.name, my_args.lxcpath[0]);
 	if (!c)
-		return -1;
+		return 1;
 
 	if (!c->may_control(c)) {
 		ERROR("Insufficent privileges to control %s:%s", my_args.lxcpath[0], my_args.name);
 		lxc_container_put(c);
-		return -1;
+		return 1;
 	}
 
 	if (!c->is_running(c)) {
 		ERROR("'%s:%s' is not running", my_args.lxcpath[0], my_args.name);
 		lxc_container_put(c);
-		return -1;
+		return 1;
 	}
 
 	if ((my_args.argc) > 1) {
@@ -102,7 +102,7 @@ int main(int argc, char *argv[])
 			ERROR("failed to assign '%s' value to '%s' for '%s'",
 				value, state_object, my_args.name);
 			lxc_container_put(c);
-			return -1;
+			return 1;
 		}
 	} else {
 		int len = 4096;
@@ -112,7 +112,7 @@ int main(int argc, char *argv[])
 			ERROR("failed to retrieve value of '%s' for '%s:%s'",
 			      state_object, my_args.lxcpath[0], my_args.name);
 			lxc_container_put(c);
-			return -1;
+			return 1;
 		}
 		printf("%*s", ret, buffer);
 	}

src/lxc/lxc_clone.c

@@ -176,7 +176,7 @@ int main(int argc, char *argv[])
 	if (!c1->may_control(c1)) {
 		fprintf(stderr, "Insufficent privileges to control %s\n", orig);
 		lxc_container_put(c1);
-		return -1;
+		return 1;
 	}
 
 	if (!c1->is_defined(c1)) {

src/lxc/lxc_config.c

@@ -70,5 +70,5 @@ int main(int argc, char *argv[])
 		}
 	}
 	printf("Unknown configuration item: %s\n", argv[1]);
-	exit(-1);
+	exit(1);
 }

src/lxc/lxc_console.c

@@ -115,7 +115,7 @@ int main(int argc, char *argv[])
 	if (!c->may_control(c)) {
 		fprintf(stderr, "Insufficent privileges to control %s\n", my_args.name);
 		lxc_container_put(c);
-		return -1;
+		exit(EXIT_FAILURE);
 	}
 
 	if (!c->is_running(c)) {

src/lxc/lxc_destroy.c

@@ -83,7 +83,7 @@ int main(int argc, char *argv[])
 	if (!c->may_control(c)) {
 		fprintf(stderr, "Insufficent privileges to control %s\n", my_args.name);
 		lxc_container_put(c);
-		return -1;
+		exit(1);
 	}
 
 	if (!c->is_defined(c)) {
@@ -108,5 +108,5 @@ int main(int argc, char *argv[])
 	}
 
 	lxc_container_put(c);
-	return 0;
+	exit(0);
 }

src/lxc/lxc_execute.c

@@ -91,18 +91,19 @@ int main(int argc, char *argv[])
 {
 	char *rcfile;
 	struct lxc_conf *conf;
+	int ret;
 
 	lxc_list_init(&defines);
 
 	if (lxc_caps_init())
-		return -1;
+		return 1;
 
 	if (lxc_arguments_parse(&my_args, argc, argv))
-		return -1;
+		return 1;
 
 	if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
 			 my_args.progname, my_args.quiet, my_args.lxcpath[0]))
-		return -1;
+		return 1;
 	lxc_log_options_no_override();
 
 	/* rcfile is specified in the cli option */
@@ -114,7 +115,7 @@ int main(int argc, char *argv[])
 		rc = asprintf(&rcfile, "%s/%s/config", my_args.lxcpath[0], my_args.name);
 		if (rc == -1) {
 			SYSERROR("failed to allocate memory");
-			return -1;
+			return 1;
 		}
 
 		/* container configuration does not exist */
@@ -127,16 +128,19 @@ int main(int argc, char *argv[])
 	conf = lxc_conf_init();
 	if (!conf) {
 		ERROR("failed to initialize configuration");
-		return -1;
+		return 1;
 	}
 
 	if (rcfile && lxc_config_read(rcfile, conf)) {
 		ERROR("failed to read configuration file");
-		return -1;
+		return 1;
 	}
 
 	if (lxc_config_define_load(&defines, conf))
-		return -1;
+		return 1;
 
-	return lxc_execute(my_args.name, my_args.argv, my_args.quiet, conf, my_args.lxcpath[0]);
+	ret = lxc_execute(my_args.name, my_args.argv, my_args.quiet, conf, my_args.lxcpath[0]);
+	if (ret < 0)
+		return 1;
+	return ret;
 }

src/lxc/lxc_freeze.c

@@ -77,7 +77,7 @@ int main(int argc, char *argv[])
 	if (!c->may_control(c)) {
 		ERROR("Insufficent privileges to control %s:%s", my_args.lxcpath[0], my_args.name);
 		lxc_container_put(c);
-		return -1;
+		exit(1);
 	}
 
 	if (!c->freeze(c)) {
@@ -88,5 +88,5 @@ int main(int argc, char *argv[])
 
 	lxc_container_put(c);
 
-	return 0;
+	exit(0);
 }

src/lxc/lxc_init.c

@@ -260,5 +260,7 @@ int main(int argc, char *argv[])
 		}
 	}
 out:
-	return err;
+	if (err < 0)
+		exit(EXIT_FAILURE);
+	exit(err);
 }

src/lxc/lxc_monitor.c

@@ -78,14 +78,14 @@ int main(int argc, char *argv[])
 	int len, rc, i, nfds = -1;
 
 	if (lxc_arguments_parse(&my_args, argc, argv))
-		return -1;
+		return 1;
 
 	if (!my_args.log_file)
 		my_args.log_file = "none";
 
 	if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
 			 my_args.progname, my_args.quiet, my_args.lxcpath[0]))
-		return -1;
+		return 1;
 	lxc_log_options_no_override();
 
 	if (quit_monitord) {
@@ -114,19 +114,19 @@ int main(int argc, char *argv[])
 	regexp = malloc(len + 3);
 	if (!regexp) {
 		ERROR("failed to allocate memory");
-		return -1;
+		return 1;
 	}
 	rc = snprintf(regexp, len, "^%s$", my_args.name);
 	if (rc < 0 || rc >= len) {
 		ERROR("Name too long");
 		free(regexp);
-		return -1;
+		return 1;
 	}
 
 	if (regcomp(&preg, regexp, REG_NOSUB|REG_EXTENDED)) {
 		ERROR("failed to compile the regex '%s'", my_args.name);
 		free(regexp);
-		return -1;
+		return 1;
 	}
 	free(regexp);
 
@@ -144,7 +144,7 @@ int main(int argc, char *argv[])
 		fd = lxc_monitor_open(my_args.lxcpath[i]);
 		if (fd < 0) {
 			regfree(&preg);
-			return -1;
+			return 1;
 		}
 		FD_SET(fd, &rfds);
 		if (fd > nfds)
@@ -160,7 +160,7 @@ int main(int argc, char *argv[])
 
 		if (lxc_monitor_read_fdset(&rfds, nfds, &msg, -1) < 0) {
 			regfree(&preg);
-			return -1;
+			return 1;
 		}
 
 		msg.name[sizeof(msg.name)-1] = '\0';

src/lxc/lxc_monitord.c

@@ -378,7 +378,7 @@ int main(int argc, char *argv[])
 	    sigdelset(&mask, SIGTERM) ||
 	    sigprocmask(SIG_BLOCK, &mask, NULL)) {
 		SYSERROR("failed to set signal mask");
-		return -1;
+		return 1;
 	}
 
 	signal(SIGILL,  lxc_monitord_sig_handler);
@@ -428,5 +428,7 @@ int main(int argc, char *argv[])
 	ret = EXIT_SUCCESS;
 	NOTICE("monitor exiting");
 out:
-	return ret;
+	if (ret == 0)
+		return 0;
+	return 1;
 }

src/lxc/lxc_snapshot.c

@@ -179,7 +179,7 @@ int main(int argc, char *argv[])
 
 	if (my_args.argc > 1) {
 		ERROR("Too many arguments");
-		return -1;
+		exit(1);
 	}
 	if (my_args.argc == 1)
 		newname = my_args.argv[0];
@@ -205,7 +205,7 @@ int main(int argc, char *argv[])
 	if (!c->may_control(c)) {
 		fprintf(stderr, "Insufficent privileges to control %s\n", my_args.name);
 		lxc_container_put(c);
-		return -1;
+		exit(1);
 	}
 
 	switch(action) {
@@ -225,5 +225,7 @@ int main(int argc, char *argv[])
 
 	lxc_container_put(c);
 
-	exit(ret);
+	if (ret == 0)
+		exit(EXIT_SUCCESS);
+	exit(EXIT_FAILURE);
 }

src/lxc/lxc_stop.c

@@ -236,5 +236,7 @@ int main(int argc, char *argv[])
 
 out:
 	lxc_container_put(c);
+	if (ret < 0)
+		return 1;
 	return ret;
 }

src/lxc/lxc_unfreeze.c

@@ -75,7 +75,7 @@ int main(int argc, char *argv[])
 	if (!c->may_control(c)) {
 		ERROR("Insufficent privileges to control %s:%s", my_args.lxcpath[0], my_args.name);
 		lxc_container_put(c);
-		return -1;
+		exit(1);
 	}
 
 	if (!c->unfreeze(c)) {
@@ -86,5 +86,5 @@ int main(int argc, char *argv[])
 
 	lxc_container_put(c);
 
-	return 0;
+	exit(0);
 }

src/lxc/lxc_unshare.c

@@ -211,7 +211,7 @@ int main(int argc, char *argv[])
 
 	ret = lxc_caps_init();
 	if (ret)
-		return ret;
+		return 1;
 
 	ret = lxc_fill_namespace_flags(namespaces, &flags);
 	if (ret)
@@ -235,7 +235,7 @@ int main(int argc, char *argv[])
 	pid = lxc_clone(do_start, &start_arg, flags);
 	if (pid < 0) {
 		ERROR("failed to clone");
-		return -1;
+		return 1;
 	}
 
 	if (my_iflist) {
@@ -250,7 +250,7 @@ int main(int argc, char *argv[])
 
 	if (waitpid(pid, &status, 0) < 0) {
 		ERROR("failed to wait for '%d'", pid);
-		return -1;
+		return 1;
 	}
 
 	return  lxc_error_set_and_log(pid, status);

src/lxc/lxc_usernsexec.c

@@ -364,7 +364,7 @@ int main(int argc, char *argv[])
 
 	if ((ret = waitpid(pid, &status, __WALL)) < 0) {
 		printf("waitpid() returns %d, errno %d\n", ret, errno);
-		exit(ret);
+		exit(1);
 	}
 
 	exit(WEXITSTATUS(status));

src/lxc/lxc_wait.c

@@ -84,29 +84,29 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 
 	if (lxc_arguments_parse(&my_args, argc, argv))
-		return -1;
+		return 1;
 
 	if (!my_args.log_file)
 		my_args.log_file = "none";
 
 	if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
 			 my_args.progname, my_args.quiet, my_args.lxcpath[0]))
-		return -1;
+		return 1;
 	lxc_log_options_no_override();
 
 	c = lxc_container_new(my_args.name, my_args.lxcpath[0]);
 	if (!c)
-		return -1;
+		return 1;
 
 	if (!c->may_control(c)) {
 		fprintf(stderr, "Insufficent privileges to control %s\n", c->name);
 		lxc_container_put(c);
-		return -1;
+		return 1;
 	}
 
 	if (!c->wait(c, my_args.states, my_args.timeout)) {
 		lxc_container_put(c);
-		return -1;
+		return 1;
 	}
 	return 0;
 }