Function walkdir

src/common/file_utils.c:155–211

* walkdir: recursively walk a directory, applying the action to each * regular file and directory (including the named directory itself). * * If process_symlinks is true, the action and recursion are also applied * to regular files and directories that are pointed to by symlinks in the * given directory; otherwise symlinks are ignored. Symlinks are always * ignored in subdirectories, ie we

 * See also walkdir in fd.c, which is a backend version of this logic.
 */
static void
walkdir(const char *path,
		int (*action) (const char *fname, bool isdir),
		bool process_symlinks)
{
	DIR		   *dir;
	struct dirent *de;

	dir = opendir(path);
	if (dir == NULL)
	{
		pg_log_error("could not open directory \"%s\": %m", path);
		return;
	}

	while (errno = 0, (de = readdir(dir)) != NULL)
	{
		char		subpath[MAXPGPATH * 2];

		if (strcmp(de->d_name, ".") == 0 ||
			strcmp(de->d_name, "..") == 0)
			continue;

		snprintf(subpath, sizeof(subpath), "%s/%s", path, de->d_name);

		switch (get_dirent_type(subpath, de, process_symlinks, PG_LOG_ERROR))
		{
			case PGFILETYPE_REG:
				(*action) (subpath, false);
				break;
			case PGFILETYPE_DIR:
				walkdir(subpath, action, false);
				break;
			default:

				/*
				 * Errors are already reported directly by get_dirent_type(),
				 * and any remaining symlinks and unknown file types are
				 * ignored.
				 */
				break;
		}
	}

	if (errno)
		pg_log_error("could not read directory \"%s\": %m", path);

	(void) closedir(dir);

	/*
	 * It's important to fsync the destination directory itself as individual
	 * file fsyncs don't guarantee that the directory entry for the file is
	 * synced.  Recent versions of ext4 have made the window much wider but
	 * it's been an issue for ext3 and other filesystems in the past.
	 */
	(*action) (path, true);
}