Mercurial > hg
view mercurial/node.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 | 1070df141718 |
children | bd872f64a8ba |
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# node.py - basic nodeid manipulation for mercurial # # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import binascii # This ugly style has a noticeable effect in manifest parsing hex = binascii.hexlify bin = binascii.unhexlify nullrev = -1 nullid = b"\0" * 20 nullhex = hex(nullid) # Phony node value to stand-in for new files in some uses of # manifests. newnodeid = '!' * 20 addednodeid = ('0' * 15) + 'added' modifiednodeid = ('0' * 12) + 'modified' wdirnodes = set((newnodeid, addednodeid, modifiednodeid)) # pseudo identifiers for working directory # (they are experimental, so don't add too many dependencies on them) wdirrev = 0x7fffffff wdirid = b"\xff" * 20 def short(node): return hex(node[:6])