Mercurial > hg
view tests/readlink.py @ 31209:dd2364f5180a
localrepo: handle rename with hardlinks properly
In "aftertrans", we rename "journal.*" to "undo.*". We expect "journal.*"
files to disappear after renaming.
However, if "journal.foo" and "undo.foo" refer to a same file (hardlink),
rename may be a no-op, leaving both files on disk, according to Linux
manpage [1]:
If oldpath and newpath are existing hard links referring to the same
file, then rename() does nothing, and returns a suc‐ cess status.
The POSIX specification [2] is not very clear about what to do.
To be safe, remove "undo.*" before the rename so "journal.*" cannot be left
on disk.
[1]: http://man7.org/linux/man-pages/man2/rename.2.html
[2]: http://pubs.opengroup.org/onlinepubs/9699919799/
author | Jun Wu <quark@fb.com> |
---|---|
date | Thu, 02 Mar 2017 21:49:30 -0800 |
parents | 6a98f9408a50 |
children | c102b704edb5 |
line wrap: on
line source
#!/usr/bin/env python from __future__ import absolute_import, print_function import errno import os import sys for f in sys.argv[1:]: try: print(f, '->', os.readlink(f)) except OSError as err: if err.errno != errno.EINVAL: raise print(f, '->', f, 'not a symlink') sys.exit(0)