diff options
Diffstat (limited to 'Lib/os.py')
| -rw-r--r-- | Lib/os.py | 80 |
1 files changed, 64 insertions, 16 deletions
@@ -61,6 +61,10 @@ if 'posix' in _names: except ImportError: pass + import posix + __all__.extend(_get_exports_list(posix)) + del posix + elif 'nt' in _names: name = 'nt' linesep = '\r\n' @@ -319,7 +323,7 @@ def walk(top, topdown=True, onerror=None, followlinks=False): the value of topdown, the list of subdirectories is retrieved before the tuples for the directory and its subdirectories are generated. - By default errors from the os.listdir() call are ignored. If + By default errors from the os.scandir() call are ignored. If optional arg 'onerror' is specified, it should be a function; it will be called with one argument, an OSError instance. It can report the error to continue with the walk, or raise the exception @@ -348,7 +352,8 @@ def walk(top, topdown=True, onerror=None, followlinks=False): """ - islink, join, isdir = path.islink, path.join, path.isdir + dirs = [] + nondirs = [] # We may not have read permission for top, in which case we can't # get a list of the files the directory contains. os.walk @@ -356,28 +361,71 @@ def walk(top, topdown=True, onerror=None, followlinks=False): # minor reason when (say) a thousand readable directories are still # left to visit. That logic is copied here. try: - # Note that listdir is global in this module due + # Note that scandir is global in this module due # to earlier import-*. - names = listdir(top) - except OSError as err: + scandir_it = scandir(top) + except OSError as error: if onerror is not None: - onerror(err) + onerror(error) return - dirs, nondirs = [], [] - for name in names: - if isdir(join(top, name)): - dirs.append(name) + while True: + try: + try: + entry = next(scandir_it) + except StopIteration: + break + except OSError as error: + if onerror is not None: + onerror(error) + return + + try: + is_dir = entry.is_dir() + except OSError: + # If is_dir() raises an OSError, consider that the entry is not + # a directory, same behaviour than os.path.isdir(). + is_dir = False + + if is_dir: + dirs.append(entry.name) else: - nondirs.append(name) + nondirs.append(entry.name) + if not topdown and is_dir: + # Bottom-up: recurse into sub-directory, but exclude symlinks to + # directories if followlinks is False + if followlinks: + walk_into = True + else: + try: + is_symlink = entry.is_symlink() + except OSError: + # If is_symlink() raises an OSError, consider that the + # entry is not a symbolic link, same behaviour than + # os.path.islink(). + is_symlink = False + walk_into = not is_symlink + + if walk_into: + yield from walk(entry.path, topdown, onerror, followlinks) + + # Yield before recursion if going top down if topdown: yield top, dirs, nondirs - for name in dirs: - new_path = join(top, name) - if followlinks or not islink(new_path): - yield from walk(new_path, topdown, onerror, followlinks) - if not topdown: + + # Recurse into sub-directories + islink, join = path.islink, path.join + for name in dirs: + new_path = join(top, name) + # Issue #23605: os.path.islink() is used instead of caching + # entry.is_symlink() result during the loop on os.scandir() because + # the caller can replace the directory entry during the "yield" + # above. + if followlinks or not islink(new_path): + yield from walk(new_path, topdown, onerror, followlinks) + else: + # Yield after recursion if going bottom up yield top, dirs, nondirs __all__.append("walk") |