keyfile: cleanup _internal_write_connection()th/keyfile-cleanup

- use gs_free instead of explicit free().

- use nm_streq*() instead of strcmp().

- move deletion of existing file after we successfully wrote
  the new file.

- add parameter existing_path_readonly, to avoid to overwrite or
  delete the existing path (if it exists). This is still mostly unused,
  but will be necessary when we have read-only directories.

1 files changed, 35 insertions, 27 deletions

diff --git a/src/settings/plugins/keyfile/nms-keyfile-writer.c b/src/settings/plugins/keyfile/nms-keyfile-writer.c
index 2536378613..8c75d8c799 100644
--- a/src/settings/plugins/keyfile/nms-keyfile-writer.c
+++ b/src/settings/plugins/keyfile/nms-keyfile-writer.c
@@ -175,15 +175,16 @@ _internal_write_connection (NMConnection *connection,
                             uid_t owner_uid,
                             pid_t owner_grp,
                             const char *existing_path,
+                            gboolean existing_path_read_only,
                             gboolean force_rename,
                             char **out_path,
                             NMConnection **out_reread,
                             gboolean *out_reread_same,
                             GError **error)
 {
-	gs_unref_keyfile GKeyFile *key_file = NULL;
-	gs_free char *data = NULL;
-	gsize len;
+	gs_unref_keyfile GKeyFile *kf_file = NULL;
+	gs_free char *kf_content_buf = NULL;
+	gsize kf_content_len;
 	gs_free char *path = NULL;
 	const char *id;
 	WriteInfo info = { 0 };
@@ -195,6 +196,7 @@ _internal_write_connection (NMConnection *connection,
 	g_return_val_if_fail (keyfile_dir && keyfile_dir[0] == '/', FALSE);
 
 	rename =    force_rename
+	         || existing_path_read_only
 	         || (   existing_path
 	             && !nm_utils_file_is_in_path (existing_path, keyfile_dir));
 
@@ -213,11 +215,11 @@ _internal_write_connection (NMConnection *connection,
 
 	info.keyfile_dir = keyfile_dir;
 
-	key_file = nm_keyfile_write (connection, _handler_write, &info, error);
-	if (!key_file)
+	kf_file = nm_keyfile_write (connection, _handler_write, &info, error);
+	if (!kf_file)
 		return FALSE;
-	data = g_key_file_to_data (key_file, &len, error);
-	if (!data)
+	kf_content_buf = g_key_file_to_data (kf_file, &kf_content_len, error);
+	if (!kf_content_buf)
 		return FALSE;
 
 	if (!g_file_test (keyfile_dir, G_FILE_TEST_IS_DIR))
@@ -226,13 +228,14 @@ _internal_write_connection (NMConnection *connection,
 	/* If we have existing file path, use it. Else generate one from
 	 * connection's ID.
 	 */
-	if (existing_path != NULL && !rename) {
+	if (   existing_path
+	    && !rename)
 		path = g_strdup (existing_path);
-	} else {
-		char *filename_escaped = nm_keyfile_utils_create_filename (id, with_extension);
+	else {
+		gs_free char *filename_escaped = NULL;
 
+		filename_escaped = nm_keyfile_utils_create_filename (id, with_extension);
 		path = g_build_filename (keyfile_dir, filename_escaped, NULL);
-		g_free (filename_escaped);
 	}
 
 	/* If a file with this path already exists (but isn't the existing path
@@ -242,13 +245,15 @@ _internal_write_connection (NMConnection *connection,
 	 * there's a race here, but there's not a lot we can do about it, and
 	 * we shouldn't get more than one connection with the same UUID either.
 	 */
-	if (g_strcmp0 (path, existing_path) != 0 && g_file_test (path, G_FILE_TEST_EXISTS)) {
+	if (   !nm_streq0 (path, existing_path)
+	    && g_file_test (path, G_FILE_TEST_EXISTS)) {
 		guint i;
 		gboolean name_found = FALSE;
 
 		/* A keyfile with this connection's ID already exists. Pick another name. */
 		for (i = 0; i < 100; i++) {
-			char *filename, *filename_escaped;
+			gs_free char *filename_escaped = NULL;
+			gs_free char *filename = NULL;
 
 			if (i == 0)
 				filename = g_strdup_printf ("%s-%s", id, nm_connection_get_uuid (connection));
@@ -259,15 +264,15 @@ _internal_write_connection (NMConnection *connection,
 
 			g_free (path);
 			path = g_strdup_printf ("%s/%s", keyfile_dir, filename_escaped);
-			g_free (filename);
-			g_free (filename_escaped);
-			if (g_strcmp0 (path, existing_path) == 0 || !g_file_test (path, G_FILE_TEST_EXISTS)) {
+
+			if (   nm_streq0 (path, existing_path)
+			    || !g_file_test (path, G_FILE_TEST_EXISTS)) {
 				name_found = TRUE;
 				break;
 			}
 		}
 		if (!name_found) {
-			if (existing_path == NULL) {
+			if (existing_path_read_only || !existing_path) {
 				/* this really should not happen, we tried hard to find an unused name... bail out. */
 				g_set_error (error, NM_SETTINGS_ERROR, NM_SETTINGS_ERROR_FAILED,
 				                    "could not find suitable keyfile file name (%s already used)", path);
@@ -280,13 +285,7 @@ _internal_write_connection (NMConnection *connection,
 		}
 	}
 
-	/* In case of updating the connection and changing the file path,
-	 * we need to remove the old one, not to end up with two connections.
-	 */
-	if (existing_path != NULL && strcmp (path, existing_path) != 0)
-		unlink (existing_path);
-
-	nm_utils_file_set_contents (path, data, len, 0600, &local_err);
+	nm_utils_file_set_contents (path, kf_content_buf, kf_content_len, 0600, &local_err);
 	if (local_err) {
 		g_set_error (error, NM_SETTINGS_ERROR, NM_SETTINGS_ERROR_FAILED,
 		             "error writing to file '%s': %s",
@@ -304,12 +303,19 @@ _internal_write_connection (NMConnection *connection,
 		return FALSE;
 	}
 
-	if (out_reread || out_reread_same)
-	{
+	/* In case of updating the connection and changing the file path,
+	 * we need to remove the old one, not to end up with two connections.
+	 */
+	if (   existing_path
+	    && !existing_path_read_only
+	    && !nm_streq (path, existing_path))
+		unlink (existing_path);
+
+	if (out_reread || out_reread_same) {
 		gs_unref_object NMConnection *reread = NULL;
 		gboolean reread_same = FALSE;
 
-		reread = nms_keyfile_reader_from_keyfile (key_file, path, NULL, profile_dir, FALSE, NULL);
+		reread = nms_keyfile_reader_from_keyfile (kf_file, path, NULL, profile_dir, FALSE, NULL);
 
 		nm_assert (NM_IS_CONNECTION (reread));
 
@@ -364,6 +370,7 @@ nms_keyfile_writer_connection (NMConnection *connection,
 	                                   0,
 	                                   0,
 	                                   existing_path,
+	                                   FALSE,
 	                                   force_rename,
 	                                   out_path,
 	                                   out_reread,
@@ -389,6 +396,7 @@ nms_keyfile_writer_test_connection (NMConnection *connection,
 	                                   owner_grp,
 	                                   NULL,
 	                                   FALSE,
+	                                   FALSE,
 	                                   out_path,
 	                                   out_reread,
 	                                   out_reread_same,