lock: Use a global variable in lock.c to keep lock file descriptor

For many different reasons it isn't possible to use swupd_init to
initialize multiple state directories in the same execution of swupd.
Lock function is also tied to a single swupd state directory because
it's using state_dir global, so moving the lock_fd variable to lock.c
won't reduce lock function versatility and it will make swupd_init and
swupd_deinit code easier to read.

src/bundle.c

@@ -481,7 +481,6 @@ out:
  */
 int remove_bundles(char **bundles)
 {
-	int lock_fd;
 	int ret = 0;
 	int ret_code = 0;
 	int bad = 0;
@@ -491,7 +490,7 @@ int remove_bundles(char **bundles)
 	struct list *subs = NULL;
 	bool mix_exists;
 
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Failed updater initialization, exiting now.\n");
 		return ret;
@@ -511,7 +510,7 @@ int remove_bundles(char **bundles)
 			  ret);
 
 		free_subscriptions(&subs);
-		swupd_deinit(lock_fd);
+		swupd_deinit();
 		return ret;
 	}
 
@@ -648,7 +647,7 @@ int remove_bundles(char **bundles)
 	}
 
 	free_subscriptions(&subs);
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 
 	return ret_code;
 }
@@ -1032,7 +1031,6 @@ out:
  */
 int install_bundles_frontend(char **bundles)
 {
-	int lock_fd;
 	int ret = 0;
 	int current_version;
 	struct list *bundles_list = NULL;
@@ -1043,7 +1041,7 @@ int install_bundles_frontend(char **bundles)
 	bool mix_exists;
 
 	/* initialize swupd and get current version from OS */
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Failed updater initialization, exiting now.\n");
 		return ret;
@@ -1101,7 +1099,7 @@ clean_and_exit:
 
 	free_string(&bundles_list_str);
 	free_subscriptions(&subs);
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 
 	return ret;
 }

src/clean.c

@@ -322,8 +322,7 @@ int clean_main(int argc, char **argv)
 	}
 
 	int ret = 0;
-	int lock_fd = 0;
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Failed swupd initialization, exiting now.\n");
 		return ret;
@@ -354,7 +353,7 @@ int clean_main(int argc, char **argv)
 	}
 
 end:
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 	return ret;
 }
 

src/clr_bundle_ls.c

@@ -182,7 +182,6 @@ err:
 
 int bundle_list_main(int argc, char **argv)
 {
-	int lock_fd;
 	int ret;
 
 	if (!parse_options(argc, argv)) {
@@ -198,7 +197,7 @@ int bundle_list_main(int argc, char **argv)
 		return ret;
 	}
 
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Error: Failed updater initialization. Exiting now\n");
 		return ret;
@@ -212,7 +211,7 @@ int bundle_list_main(int argc, char **argv)
 		ret = list_installable_bundles();
 	}
 
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 
 	return ret;
 }

src/helpers.c

@@ -521,24 +521,26 @@ void free_file_data(void *data)
 	free(file);
 }
 
-void swupd_deinit(int lock_fd)
+void swupd_deinit(void)
 {
 	terminate_signature();
 	swupd_curl_deinit();
 	free_globals();
-	v_lockfile(lock_fd);
+	v_lockfile();
 	dump_file_descriptor_leaks();
 }
 
 /* this function is intended to encapsulate the basic swupd
 * initializations for the majority of commands, that is:
 * 	- Make sure root is the user running the code
-*	- Initialize log facility
-*	- Get the lock
+* 	- Initialize globals
 *	- initialize mounted directories
+*	- Create necessary directories
+*	- Get the lock
 *	- Initialize curl
+*	- Initialize signature checking
 */
-int swupd_init(int *lock_fd)
+int swupd_init(void)
 {
 	int ret = 0;
 
@@ -566,8 +568,7 @@ int swupd_init(int *lock_fd)
 		goto out_fds;
 	}
 
-	*lock_fd = p_lockfile();
-	if (*lock_fd < 0) {
+	if (p_lockfile() < 0) {
 		ret = ELOCK_FILE;
 		goto out_fds;
 	}
@@ -587,7 +588,7 @@ int swupd_init(int *lock_fd)
 	return ret;
 
 out_close_lock:
-	v_lockfile(*lock_fd);
+	v_lockfile();
 out_fds:
 	dump_file_descriptor_leaks();
 

src/lock.c

@@ -38,13 +38,19 @@
 #include "config.h"
 #include "swupd.h"
 
+static int lock_fd = -1;
+
 /* Try to get a write lock region on the lock file. Returns:
 * >= 0 an fcntl region lock'd fd or exits with a positive error
 * code and a recommended course of action for user.
 */
 int p_lockfile(void)
 {
-	int lock_fd, ret;
+	if (lock_fd > 0) {
+		return -1;
+	}
+
+	int ret;
 	pid_t pid = getpid();
 	struct flock fl = {
 		.l_type = F_WRLCK,
@@ -89,7 +95,9 @@ int p_lockfile(void)
 }
 
 /* closes lock fd and must not unlink lock file (else race allowed) */
-void v_lockfile(int fd)
+void v_lockfile(void)
 {
-	close(fd);
+	if (lock_fd > 0) {
+		close(lock_fd);
+	}
 }

src/search.c

@@ -856,7 +856,6 @@ static int download_manifests(struct manifest **MoM, struct list **subs)
 int search_main(int argc, char **argv)
 {
 	int ret = 0;
-	int lock_fd = 0;
 	struct manifest *MoM = NULL;
 	struct list *subs = NULL;
 
@@ -864,7 +863,7 @@ int search_main(int argc, char **argv)
 		return EINVALID_OPTION;
 	}
 
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Failed swupd initialization, exiting now.\n");
 		return ret;
@@ -899,6 +898,6 @@ int search_main(int argc, char **argv)
 clean_exit:
 	free_manifest(MoM);
 	free_subscriptions(&subs);
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 	return ret;
 }

src/swupd.h

@@ -350,14 +350,14 @@ extern void record_fds(void);
 
 /* lock.c */
 int p_lockfile(void);
-void v_lockfile(int fd);
+void v_lockfile(void);
 
 /* helpers.c */
 extern int swupd_rm(const char *path);
 extern int rm_bundle_file(const char *bundle);
 extern void print_manifest_files(struct manifest *m);
-extern void swupd_deinit(int lock_fd);
-extern int swupd_init(int *lock_fd);
+extern void swupd_deinit(void);
+extern int swupd_init(void);
 extern void string_or_die(char **strp, const char *fmt, ...);
 char *strdup_or_die(const char *const str);
 extern void free_string(char **s);

src/update.c

@@ -212,7 +212,6 @@ static int main_update()
 	struct list *current_subs = NULL;
 	struct list *latest_subs = NULL;
 	int ret;
-	int lock_fd;
 	int retries = 0;
 	int timeout = 10;
 	struct timespec ts_start, ts_stop; // For main swupd update time
@@ -224,7 +223,7 @@ static int main_update()
 
 	srand(time(NULL));
 
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		/* being here means we already close log by a previously caught error */
 		fprintf(stderr, "Updater failed to initialize, exiting now.\n");
@@ -548,7 +547,7 @@ clean_curl:
 	 * we need and the clean helps us prevent cache bloat. */
 	clean_statedir(false, false);
 	free_subscriptions(&latest_subs);
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 
 	if (nonpack > 0) {
 		printf("%i files were not in a pack\n", nonpack);

src/verify.c

@@ -698,7 +698,6 @@ int verify_main(int argc, char **argv)
 {
 	struct manifest *official_manifest = NULL;
 	int ret;
-	int lock_fd;
 	int retries = 0;
 	int timeout = 10;
 	struct list *subs = NULL;
@@ -713,7 +712,7 @@ int verify_main(int argc, char **argv)
 	assert(argc >= 0);
 	assert(argv != NULL);
 
-	ret = swupd_init(&lock_fd);
+	ret = swupd_init();
 	if (ret != 0) {
 		fprintf(stderr, "Failed verify initialization, exiting now.\n");
 		goto clean_args_and_exit;
@@ -1020,7 +1019,7 @@ clean_and_exit:
 
 	print_time_stats(&times);
 	free_subscriptions(&subs);
-	swupd_deinit(lock_fd);
+	swupd_deinit();
 
 clean_args_and_exit:
 	if (picky_whitelist) {