From c48fe98a7c3bb48fd689088baf3fedf9da7a8c70 Mon Sep 17 00:00:00 2001 From: Larry Hastings Date: Mon, 25 Jun 2012 04:49:05 -0700 Subject: Issue #15177: Added dir_fd parameter to os.fwalk(). --- Lib/os.py | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'Lib/os.py') diff --git a/Lib/os.py b/Lib/os.py index f990627267..381737fcd2 100644 --- a/Lib/os.py +++ b/Lib/os.py @@ -422,9 +422,9 @@ def walk(top, topdown=True, onerror=None, followlinks=False): __all__.append("walk") -if open in supports_dir_fd: +if {open, stat} <= supports_dir_fd and {listdir, stat} <= supports_fd: - def fwalk(top, topdown=True, onerror=None, followlinks=False): + def fwalk(top=".", topdown=True, onerror=None, followlinks=False, *, dir_fd=None): """Directory tree generator. This behaves exactly like walk(), except that it yields a 4-tuple @@ -434,9 +434,13 @@ if open in supports_dir_fd: `dirpath`, `dirnames` and `filenames` are identical to walk() output, and `dirfd` is a file descriptor referring to the directory `dirpath`. - The advantage of walkfd() over walk() is that it's safe against symlink + The advantage of fwalk() over walk() is that it's safe against symlink races (when followlinks is False). + If dir_fd is not None, it should be a file descriptor open to a directory, + and top should be relative; top will then be relative to that directory. + (dir_fd is always supported for fwalk.) + Caution: Since fwalk() yields file descriptors, those are only valid until the next iteration step, so you should dup() them if you want to keep them @@ -455,11 +459,11 @@ if open in supports_dir_fd: """ # Note: To guard against symlink races, we use the standard # lstat()/open()/fstat() trick. - orig_st = lstat(top) - topfd = open(top, O_RDONLY) + orig_st = stat(top, follow_symlinks=False, dir_fd=dir_fd) + topfd = open(top, O_RDONLY, dir_fd=dir_fd) try: if (followlinks or (st.S_ISDIR(orig_st.st_mode) and - path.samestat(orig_st, fstat(topfd)))): + path.samestat(orig_st, stat(topfd)))): yield from _fwalk(topfd, top, topdown, onerror, followlinks) finally: close(topfd) @@ -502,7 +506,7 @@ if open in supports_dir_fd: onerror(err) return try: - if followlinks or path.samestat(orig_st, fstat(dirfd)): + if followlinks or path.samestat(orig_st, stat(dirfd)): dirpath = path.join(toppath, name) yield from _fwalk(dirfd, dirpath, topdown, onerror, followlinks) finally: -- cgit v1.2.1