+typedef enum {
+ FSFREEZE_HOOK_THAW = 0,
+ FSFREEZE_HOOK_FREEZE,
+} FsfreezeHookArg;
+
+const char *fsfreeze_hook_arg_string[] = {
+ "thaw",
+ "freeze",
+};
+
+static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **err)
+{
+ int status;
+ pid_t pid;
+ const char *hook;
+ const char *arg_str = fsfreeze_hook_arg_string[arg];
+ Error *local_err = NULL;
+
+ hook = ga_fsfreeze_hook(ga_state);
+ if (!hook) {
+ return;
+ }
+ if (access(hook, X_OK) != 0) {
+ error_setg_errno(err, errno, "can't access fsfreeze hook '%s'", hook);
+ return;
+ }
+
+ slog("executing fsfreeze hook with arg '%s'", arg_str);
+ pid = fork();
+ if (pid == 0) {
+ setsid();
+ reopen_fd_to_null(0);
+ reopen_fd_to_null(1);
+ reopen_fd_to_null(2);
+
+ execle(hook, hook, arg_str, NULL, environ);
+ _exit(EXIT_FAILURE);
+ } else if (pid < 0) {
+ error_setg_errno(err, errno, "failed to create child process");
+ return;
+ }
+
+ ga_wait_child(pid, &status, &local_err);
+ if (error_is_set(&local_err)) {
+ error_propagate(err, local_err);
+ return;
+ }
+
+ if (!WIFEXITED(status)) {
+ error_setg(err, "fsfreeze hook has terminated abnormally");
+ return;
+ }
+
+ status = WEXITSTATUS(status);
+ if (status) {
+ error_setg(err, "fsfreeze hook has failed with status %d", status);
+ return;
+ }
+}
+