record: don't dereference symlinks while copying over stat data
Previously, we could be calling os.utime or os.chflags (via shutil.copystat) on
a symlink. These functions dereference symlinks, so this would have caused the
timestamp of the target to be set. On a read-only or similarly weird
filesystem, this might cause an exception to be raised.
This is pretty hard to test because conjuring up a read-only filesystem for
test purposes is non-trivial.
--- a/mercurial/cmdutil.py Sat Dec 12 11:00:04 2015 -0800
+++ b/mercurial/cmdutil.py Sat Dec 12 10:58:05 2015 -0800
@@ -7,7 +7,7 @@
from node import hex, bin, nullid, nullrev, short
from i18n import _
-import os, sys, errno, re, tempfile, cStringIO, shutil
+import os, sys, errno, re, tempfile, cStringIO
import util, scmutil, templater, patch, error, templatekw, revlog, copies
import match as matchmod
import repair, graphmod, revset, phases, obsolete, pathutil
@@ -166,8 +166,7 @@
dir=backupdir)
os.close(fd)
ui.debug('backup %r as %r\n' % (f, tmpname))
- util.copyfile(repo.wjoin(f), tmpname)
- shutil.copystat(repo.wjoin(f), tmpname)
+ util.copyfile(repo.wjoin(f), tmpname, copystat=True)
backups[f] = tmpname
fp = cStringIO.StringIO()
@@ -216,15 +215,12 @@
# to be treated as unmodified
dirstate.normallookup(realname)
- util.copyfile(tmpname, repo.wjoin(realname))
- # Our calls to copystat() here and above are a
- # hack to trick any editors that have f open that
- # we haven't modified them.
+ # copystat=True here and above are a hack to trick any
+ # editors that have f open that we haven't modified them.
#
- # Also note that this racy as an editor could
- # notice the file's mtime before we've finished
- # writing it.
- shutil.copystat(tmpname, repo.wjoin(realname))
+ # Also note that this racy as an editor could notice the
+ # file's mtime before we've finished writing it.
+ util.copyfile(tmpname, repo.wjoin(realname), copystat=True)
os.unlink(tmpname)
if tobackup:
os.rmdir(backupdir)