Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitdf2d4a6

Browse files
authored
bpo-37834: Normalise handling of reparse points on Windows (GH-15231)
bpo-37834: Normalise handling of reparse points on Windows* ntpath.realpath() and nt.stat() will traverse all supported reparse points (previously was mixed)* nt.lstat() will let the OS traverse reparse points that are not name surrogates (previously would not traverse any reparse point)* nt.[l]stat() will only set S_IFLNK for symlinks (previous behaviour)* nt.readlink() will read destinations for symlinks and junction points onlybpo-1311: os.path.exists('nul') now returns True on Windows* nt.stat('nul').st_mode is now S_IFCHR (previously was an error)
1 parentbcc446f commitdf2d4a6

File tree

16 files changed

+470
-233
lines changed

16 files changed

+470
-233
lines changed

‎Doc/library/os.rst‎

Lines changed: 51 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1858,6 +1858,12 @@ features:
18581858
..versionchanged::3.6
18591859
Accepts a:term:`path-like object` for *src* and *dst*.
18601860

1861+
..versionchanged::3.8
1862+
On Windows, now opens reparse points that represent another path
1863+
(name surrogates), including symbolic links and directory junctions.
1864+
Other kinds of reparse points are resolved by the operating system as
1865+
for:func:`~os.stat`.
1866+
18611867

18621868
..function::mkdir(path, mode=0o777, *, dir_fd=None)
18631869

@@ -2039,6 +2045,10 @@ features:
20392045
This function can also support:ref:`paths relative to directory descriptors
20402046
<dir_fd>`.
20412047

2048+
When trying to resolve a path that may contain links, use
2049+
:func:`~os.path.realpath` to properly handle recursion and platform
2050+
differences.
2051+
20422052
..availability::Unix, Windows.
20432053

20442054
..versionchanged::3.2
@@ -2053,6 +2063,11 @@ features:
20532063
..versionchanged::3.8
20542064
Accepts a:term:`path-like object` and a bytes object on Windows.
20552065

2066+
..versionchanged::3.8
2067+
Added support for directory junctions, and changed to return the
2068+
substitution path (which typically includes ``\\?\`` prefix) rather
2069+
than the optional "print name" field that was previously returned.
2070+
20562071
..function::remove(path, *, dir_fd=None)
20572072

20582073
Remove (delete) the file *path*. If *path* is a directory, an
@@ -2366,7 +2381,8 @@ features:
23662381

23672382
On Unix, this method always requires a system call. On Windows, it
23682383
only requires a system call if *follow_symlinks* is ``True`` and the
2369-
entry is a symbolic link.
2384+
entry is a reparse point (for example, a symbolic link or directory
2385+
junction).
23702386

23712387
On Windows, the ``st_ino``, ``st_dev`` and ``st_nlink`` attributes of the
23722388
:class:`stat_result` are always set to zero. Call:func:`os.stat` to
@@ -2403,6 +2419,17 @@ features:
24032419
This function can support:ref:`specifying a file descriptor<path_fd>` and
24042420
:ref:`not following symlinks<follow_symlinks>`.
24052421

2422+
On Windows, passing ``follow_symlinks=False`` will disable following all
2423+
name-surrogate reparse points, which includes symlinks and directory
2424+
junctions. Other types of reparse points that do not resemble links or that
2425+
the operating system is unable to follow will be opened directly. When
2426+
following a chain of multiple links, this may result in the original link
2427+
being returned instead of the non-link that prevented full traversal. To
2428+
obtain stat results for the final path in this case, use the
2429+
:func:`os.path.realpath` function to resolve the path name as far as
2430+
possible and call:func:`lstat` on the result. This does not apply to
2431+
dangling symlinks or junction points, which will raise the usual exceptions.
2432+
24062433
..index::module: stat
24072434

24082435
Example::
@@ -2427,6 +2454,14 @@ features:
24272454
..versionchanged::3.6
24282455
Accepts a:term:`path-like object`.
24292456

2457+
..versionchanged::3.8
2458+
On Windows, all reparse points that can be resolved by the operating
2459+
system are now followed, and passing ``follow_symlinks=False``
2460+
disables following all name surrogate reparse points. If the operating
2461+
system reaches a reparse point that it is not able to follow, *stat* now
2462+
returns the information for the original path as if
2463+
``follow_symlinks=False`` had been specified instead of raising an error.
2464+
24302465

24312466
..class::stat_result
24322467

@@ -2578,7 +2613,7 @@ features:
25782613

25792614
File type.
25802615

2581-
On Windows systems, the followingattribute is also available:
2616+
On Windows systems, the followingattributes are also available:
25822617

25832618
..attribute::st_file_attributes
25842619

@@ -2587,6 +2622,12 @@ features:
25872622
:c:func:`GetFileInformationByHandle`. See the ``FILE_ATTRIBUTE_*``
25882623
constants in the:mod:`stat` module.
25892624

2625+
..attribute::st_reparse_tag
2626+
2627+
When:attr:`st_file_attributes` has the ``FILE_ATTRIBUTE_REPARSE_POINT``
2628+
set, this field contains the tag identifying the type of reparse point.
2629+
See the ``IO_REPARSE_TAG_*`` constants in the:mod:`stat` module.
2630+
25902631
The standard module:mod:`stat` defines functions and constants that are
25912632
useful for extracting information from a:c:type:`stat` structure. (On
25922633
Windows, some items are filled with dummy values.)
@@ -2614,6 +2655,14 @@ features:
26142655
..versionadded::3.7
26152656
Added the:attr:`st_fstype` member to Solaris/derivatives.
26162657

2658+
..versionadded::3.8
2659+
Added the:attr:`st_reparse_tag` member on Windows.
2660+
2661+
..versionchanged::3.8
2662+
On Windows, the:attr:`st_mode` member now identifies special
2663+
files as:const:`S_IFCHR`,:const:`S_IFIFO` or:const:`S_IFBLK`
2664+
as appropriate.
2665+
26172666
..function::statvfs(path)
26182667

26192668
Perform a:c:func:`statvfs` system call on the given path. The return value is

‎Doc/library/shutil.rst‎

Lines changed: 4 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -304,6 +304,10 @@ Directory and files operations
304304
Added a symlink attack resistant version that is used automatically
305305
if platform supports fd-based functions.
306306

307+
..versionchanged::3.8
308+
On Windows, will no longer delete the contents of a directory junction
309+
before removing the junction.
310+
307311
..attribute::rmtree.avoids_symlink_attacks
308312

309313
Indicates whether the current platform and implementation provides a

‎Doc/library/stat.rst‎

Lines changed: 10 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -425,3 +425,13 @@ for more detail on the meaning of these constants.
425425
FILE_ATTRIBUTE_VIRTUAL
426426

427427
..versionadded::3.5
428+
429+
On Windows, the following constants are available for comparing against the
430+
``st_reparse_tag`` member returned by:func:`os.lstat`. These are well-known
431+
constants, but are not an exhaustive list.
432+
433+
..data::IO_REPARSE_TAG_SYMLINK
434+
IO_REPARSE_TAG_MOUNT_POINT
435+
IO_REPARSE_TAG_APPEXECLINK
436+
437+
..versionadded::3.8

‎Doc/whatsnew/3.8.rst‎

Lines changed: 21 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -808,6 +808,21 @@ A new :func:`os.memfd_create` function was added to wrap the
808808
``memfd_create()`` syscall.
809809
(Contributed by Zackery Spytz and Christian Heimes in:issue:`26836`.)
810810

811+
On Windows, much of the manual logic for handling reparse points (including
812+
symlinks and directory junctions) has been delegated to the operating system.
813+
Specifically,:func:`os.stat` will now traverse anything supported by the
814+
operating system, while:func:`os.lstat` will only open reparse points that
815+
identify as "name surrogates" while others are opened as for:func:`os.stat`.
816+
In all cases,:attr:`stat_result.st_mode` will only have ``S_IFLNK`` set for
817+
symbolic links and not other kinds of reparse points. To identify other kinds
818+
of reparse point, check the new:attr:`stat_result.st_reparse_tag` attribute.
819+
820+
On Windows,:func:`os.readlink` is now able to read directory junctions. Note
821+
that:func:`~os.path.islink` will return ``False`` for directory junctions,
822+
and so code that checks ``islink`` first will continue to treat junctions as
823+
directories, while code that handles errors from:func:`os.readlink` may now
824+
treat junctions as links.
825+
811826

812827
os.path
813828
-------
@@ -824,6 +839,9 @@ characters or bytes unrepresentable at the OS level.
824839
environment variable and does not use:envvar:`HOME`, which is not normally set
825840
for regular user accounts.
826841

842+
:func:`~os.path.isdir` on Windows no longer returns true for a link to a
843+
non-existent directory.
844+
827845
:func:`~os.path.realpath` on Windows now resolves reparse points, including
828846
symlinks and directory junctions.
829847

@@ -912,6 +930,9 @@ format for new archives to improve portability and standards conformance,
912930
inherited from the corresponding change to the:mod:`tarfile` module.
913931
(Contributed by C.A.M. Gerlach in:issue:`30661`.)
914932

933+
:func:`shutil.rmtree` on Windows now removes directory junctions without
934+
recursively removing their contents first.
935+
915936

916937
ssl
917938
---

‎Include/fileutils.h‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -84,6 +84,7 @@ struct _Py_stat_struct {
8484
time_tst_ctime;
8585
intst_ctime_nsec;
8686
unsigned longst_file_attributes;
87+
unsigned longst_reparse_tag;
8788
};
8889
#else
8990
# define_Py_stat_struct stat

‎Lib/shutil.py‎

Lines changed: 41 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -452,7 +452,14 @@ def _copytree(entries, src, dst, symlinks, ignore, copy_function,
452452
dstname=os.path.join(dst,srcentry.name)
453453
srcobj=srcentryifuse_srcentryelsesrcname
454454
try:
455-
ifsrcentry.is_symlink():
455+
is_symlink=srcentry.is_symlink()
456+
ifis_symlinkandos.name=='nt':
457+
# Special check for directory junctions, which appear as
458+
# symlinks but we want to recurse.
459+
lstat=srcentry.stat(follow_symlinks=False)
460+
iflstat.st_reparse_tag==stat.IO_REPARSE_TAG_MOUNT_POINT:
461+
is_symlink=False
462+
ifis_symlink:
456463
linkto=os.readlink(srcname)
457464
ifsymlinks:
458465
# We can't just leave it to `copy_function` because legacy
@@ -537,6 +544,37 @@ def copytree(src, dst, symlinks=False, ignore=None, copy_function=copy2,
537544
ignore_dangling_symlinks=ignore_dangling_symlinks,
538545
dirs_exist_ok=dirs_exist_ok)
539546

547+
ifhasattr(stat,'FILE_ATTRIBUTE_REPARSE_POINT'):
548+
# Special handling for directory junctions to make them behave like
549+
# symlinks for shutil.rmtree, since in general they do not appear as
550+
# regular links.
551+
def_rmtree_isdir(entry):
552+
try:
553+
st=entry.stat(follow_symlinks=False)
554+
return (stat.S_ISDIR(st.st_mode)andnot
555+
(st.st_file_attributes&stat.FILE_ATTRIBUTE_REPARSE_POINT
556+
andst.st_reparse_tag==stat.IO_REPARSE_TAG_MOUNT_POINT))
557+
exceptOSError:
558+
returnFalse
559+
560+
def_rmtree_islink(path):
561+
try:
562+
st=os.lstat(path)
563+
return (stat.S_ISLNK(st.st_mode)or
564+
(st.st_file_attributes&stat.FILE_ATTRIBUTE_REPARSE_POINT
565+
andst.st_reparse_tag==stat.IO_REPARSE_TAG_MOUNT_POINT))
566+
exceptOSError:
567+
returnFalse
568+
else:
569+
def_rmtree_isdir(entry):
570+
try:
571+
returnentry.is_dir(follow_symlinks=False)
572+
exceptOSError:
573+
returnFalse
574+
575+
def_rmtree_islink(path):
576+
returnos.path.islink(path)
577+
540578
# version vulnerable to race conditions
541579
def_rmtree_unsafe(path,onerror):
542580
try:
@@ -547,11 +585,7 @@ def _rmtree_unsafe(path, onerror):
547585
entries= []
548586
forentryinentries:
549587
fullname=entry.path
550-
try:
551-
is_dir=entry.is_dir(follow_symlinks=False)
552-
exceptOSError:
553-
is_dir=False
554-
ifis_dir:
588+
if_rmtree_isdir(entry):
555589
try:
556590
ifentry.is_symlink():
557591
# This can only happen if someone replaces
@@ -681,7 +715,7 @@ def onerror(*args):
681715
os.close(fd)
682716
else:
683717
try:
684-
ifos.path.islink(path):
718+
if_rmtree_islink(path):
685719
# symlinks to directories are forbidden, see bug #1669
686720
raiseOSError("Cannot call rmtree on a symbolic link")
687721
exceptOSError:

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp