replace get_boot_info by is_first_boot

is_first_boot uses kernel boot id to identify
the first boot

modify save_instance_id in order to work together with is_first_boot

Author: Julio Montes

src/ccmodules/fbootcmd.c

@@ -55,11 +55,9 @@ static void fbootcmd_item(GNode* node, gpointer command_line) {
 }
 
 void fbootcmd_handler(GNode *node) {
-	bool firstboot;
 	GString* command_line = NULL;
 	LOG(MOD "fbootcmd handler running...\n");
-	get_boot_info(&firstboot, NULL);
-	if (firstboot) {
+	if (is_first_boot()) {
 		LOG(MOD "Running first boot commands\n");
 		command_line = g_string_new("");
 		g_node_children_foreach(node, G_TRAVERSE_ALL, fbootcmd_item, command_line);

src/datasources/openstack.c

@@ -147,10 +147,10 @@ bool openstack_init(bool no_network) {
 		return true;
 	}
 
-    if (no_network) {
-        LOG(MOD "config drive was not found and --no-network option was used\n");
-        return false;
-    }
+	if (no_network) {
+		LOG(MOD "config drive was not found and --no-network option was used\n");
+		return false;
+	}
 
 	if (!curl_common_init(&curl)) {
 		LOG(MOD "Curl initialize failed\n");
@@ -426,7 +426,7 @@ static void openstack_run_handler(GNode *node, __unused__ gpointer null) {
 static void openstack_process_uuid(GNode* node, __unused__ gpointer *data) {
 	if (node->data && g_strcmp0(node->data, "uuid") == 0) {
 		openstack_metadata_uuid(node->children);
-        g_node_unlink(node);
+		g_node_unlink(node);
 		g_node_destroy(node);
 	}
 }
@@ -456,9 +456,7 @@ static int openstack_metadata_keys(GNode* node) {
 
 static int openstack_metadata_hostname(GNode* node) {
 	gchar command[LINE_MAX];
-	bool firstboot = false;
-	get_boot_info(&firstboot, NULL);
-	if (firstboot) {
+	if (is_first_boot()) {
 		g_snprintf(command, LINE_MAX, HOSTNAMECTL_PATH " set-hostname '%s'", (char*)node->data);
 		return exec_task(command);
 	}

src/lib.c

@@ -65,7 +65,10 @@
 #define LOOP_MAJOR_ID 7
 #define SUDOERS_PATH SYSCONFDIR "/sudoers.d/"
 #define INSTANCE_ID_FILE DATADIR_PATH "/instance-id"
-#define LAST_INSTANCE_ID_FILE DATADIR_PATH "/last-instance-id"
+#define FIRST_BOOT_ID_FILE DATADIR_PATH "/first-boot-id"
+#define KERNEL_BOOT_ID_FILE "/proc/sys/kernel/random/boot_id"
+
+G_LOCK_DEFINE(first_boot_id_file);
 
 
 void LOG(const char *fmt, ...) {
@@ -518,89 +521,74 @@ bool umount_filesystem(const gchar* mountdir, const gchar* loop_device) {
 	return true;
 }
 
-bool save_instance_id(const gchar* instance_id) {
-	GString* id = g_string_new(instance_id);
-
-	LOG(MOD "Saving instance id '%s'\n", id->str);
-
-	if (!write_file(id, INSTANCE_ID_FILE, O_CREAT|O_TRUNC|O_WRONLY, S_IRWXU)) {
-		LOG(MOD "Unable to save instance id\n");
-		g_string_free(id, true);
-		return false;
-	}
-
-	g_string_free(id, true);
-	return true;
-}
-
-void get_boot_info(bool* firstboot, bool* snapshot) {
-	gchar* instance_id = NULL;
+bool save_instance_id(const gchar* id) {
+	bool result = false;
+	GString* instance_id = g_string_new(id);
 	gchar* last_instance_id = NULL;
 	struct stat st;
-	static int cache_firstboot = -1;
-	static int cache_snapshot = -1;
 
-	if (cache_firstboot != -1 && cache_snapshot != -1 ) {
-		if (snapshot) {
-			*snapshot = (bool)cache_snapshot;
+	if (stat(INSTANCE_ID_FILE, &st) != 0) {
+		if (!write_file(instance_id, INSTANCE_ID_FILE, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR)) {
+			LOG(MOD "Unable to save instance id\n");
+			goto exit;
 		}
-		if (firstboot) {
-			*firstboot = (bool)cache_firstboot;
-		}
-		return;
-	}
-
-	if (snapshot) {
-		*snapshot = false;
-	}
-	if (firstboot) {
-		*firstboot = false;
-	}
-
-	if (stat(LAST_INSTANCE_ID_FILE, &st) != 0) {
-		LOG(MOD "first boot! - '%s' not found\n", LAST_INSTANCE_ID_FILE);
-		if (!copy_file(INSTANCE_ID_FILE, LAST_INSTANCE_ID_FILE)) {
-			LOG(MOD "Copy file failed\n");
+	} else {
+		if (!g_file_get_contents(INSTANCE_ID_FILE, &last_instance_id, NULL, NULL)) {
+			LOG(MOD "Unable to read file '%s'\n", INSTANCE_ID_FILE);
+			goto exit;
 		}
-		if (firstboot) {
-			*firstboot = true;
+		if (g_strcmp0(instance_id->str, last_instance_id) != 0) {
+			g_free(last_instance_id);
+			if (!write_file(instance_id, INSTANCE_ID_FILE, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR)) {
+				LOG(MOD "Unable to save instance id\n");
+				goto exit;
+			}
+			result = true;
+			G_LOCK(first_boot_id_file);
+			remove(FIRST_BOOT_ID_FILE);
+			G_UNLOCK(first_boot_id_file);
 		}
-		cache_firstboot = 1;
-		cache_snapshot = 0;
-		return;
 	}
 
-	if (!g_file_get_contents(INSTANCE_ID_FILE, &instance_id, NULL, NULL)) {
-		LOG(MOD "Unable to read file '%s'\n", INSTANCE_ID_FILE);
-		return;
-	}
+exit:
+	g_string_free(instance_id, true);
+	return result;
+}
 
-	if (!g_file_get_contents(LAST_INSTANCE_ID_FILE, &last_instance_id, NULL, NULL)) {
-		LOG(MOD "Unable to read file '%s'\n", LAST_INSTANCE_ID_FILE);
-		goto fail1;
-	}
+bool is_first_boot(void) {
+	struct stat st;
+	bool firstboot = false;
+	gchar* boot_id;
+	gchar* first_boot_id;
 
-	cache_firstboot = 0;
-	cache_snapshot = 0;
+	G_LOCK(first_boot_id_file);
 
-	if (g_strcmp0(instance_id, last_instance_id) != 0) {
-		LOG(MOD "first boot!\n");
-		if (!copy_file(INSTANCE_ID_FILE, LAST_INSTANCE_ID_FILE)) {
-			LOG(MOD "Copy file failed\n");
+	if (stat(FIRST_BOOT_ID_FILE, &st) != 0) {
+		firstboot = true;
+		if (!copy_file(KERNEL_BOOT_ID_FILE, FIRST_BOOT_ID_FILE)) {
+			LOG(MOD "Copy file '%s' failed\n", KERNEL_BOOT_ID_FILE);
+			return false;
+		}
+	} else {
+		if (!g_file_get_contents(KERNEL_BOOT_ID_FILE, &boot_id, NULL, NULL)) {
+			LOG(MOD "Unable to read file '%s'\n", KERNEL_BOOT_ID_FILE);
+			goto exit;
 		}
-		if (snapshot) {
-			*snapshot = true;
+		if (!g_file_get_contents(FIRST_BOOT_ID_FILE, &first_boot_id, NULL, NULL)) {
+			LOG(MOD "Unable to read file '%s'\n", FIRST_BOOT_ID_FILE);
+			g_free(boot_id);
+			goto exit;
 		}
-		if (firstboot) {
-			*firstboot = true;
+		if (g_strcmp0(first_boot_id, boot_id) == 0) {
+			firstboot = true;
 		}
-		cache_firstboot = 1;
-		cache_snapshot = 1;
+		g_free(first_boot_id);
+		g_free(boot_id);
 	}
 
-	g_free(last_instance_id);
-fail1:
-	g_free(instance_id);
+exit:
+	G_UNLOCK(first_boot_id_file);
+	return firstboot;
 }
 
 bool gnode_free(GNode* node, __unused__ gpointer data) {

src/lib.h

@@ -56,7 +56,7 @@ void LOG(const char *fmt, ...) __attribute__((format(printf, 1, 2)));
 int make_dir(const char* pathname, mode_t mode) __warn_unused_result__;
 int chown_path(const char* pathname, const char* ownername, const char* groupname) __warn_unused_result__;
 bool save_instance_id(const gchar* instance_id) __warn_unused_result__;
-void get_boot_info(bool* firstboot, bool* snapshot);
+bool is_first_boot(void) __warn_unused_result__;
 bool write_file(const GString* data, const gchar* file_path, int oflags, mode_t mode) __warn_unused_result__;
 bool write_sudo_directives(const GString* data, const gchar* filename) __warn_unused_result__;
 bool write_ssh_keys(const GString* data, const gchar* username) __warn_unused_result__;

src/main.c

@@ -135,7 +135,6 @@ int main(int argc, char *argv[]) {
 	bool first_boot_setup = false;
 	bool first_boot = false;
 	bool no_network = false;
-	bool snapshot = false;
 	char* userdata_filename = NULL;
 	char* tmp_metadata_filename = NULL;
 	char* tmp_data_filesystem = NULL;
@@ -215,13 +214,13 @@ int main(int argc, char *argv[]) {
 			fix_disk = true;
 			break;
 
-        case OPT_FIRST_BOOT_SETUP:
-            first_boot_setup = true;
-            break;
+		case OPT_FIRST_BOOT_SETUP:
+			first_boot_setup = true;
+			break;
 
-        case OPT_NO_NETWORK:
-            no_network = true;
-            break;
+		case OPT_NO_NETWORK:
+			no_network = true;
+			break;
 		}
 	}
 
@@ -290,7 +289,7 @@ int main(int argc, char *argv[]) {
 				if (!datasource_handler->start()) {
 					result_code = EXIT_FAILURE;
 				} else if(first_boot_setup) {
-					get_boot_info(&first_boot, &snapshot);
+					first_boot = is_first_boot();
 				}
 				break;
 			}