[PATCH] Prefer lstat over stat, don't chmod symlinks

[Elliot Murphy]

Hi!

I ran into a problem today with 'bzr diff --using meld' on a branch
containing dangling symlinks (I'm using the difftools plugin). Down in
bzrlib.osutils.make_readonly, os.stat() was complaining about 'No such
file or directory' when hitting a dangling symlink.

This patch tries to use lstat instead of stat, reverting to stat on
platforms that don't have lstat (windows). It also checks to see whether
a file is a symlink and does not os.chmod() symlinks.

=== modified file 'bzrlib/osutils.py'
--- bzrlib/osutils.py   2007-05-15 22:40:39 +0000
+++ bzrlib/osutils.py   2007-06-11 22:00:01 +0000
@@ -69,18 +69,23 @@
 # OR with 0 on those platforms
 O_BINARY = getattr(os, 'O_BINARY', 0)

+# On posix, use lstat instead of stat so that we can
+# operate on broken symlinks. On Windows revert to stat.
+lstat = getattr(os, 'lstat', os.stat)

 def make_readonly(filename):
     """Make a filename read-only."""
-    mod = os.stat(filename).st_mode
-    mod = mod & 0777555
-    os.chmod(filename, mod)
+    mod = lstat(filename).st_mode
+    if not stat.S_ISLNK(mod):
+        mod = mod & 0777555
+        os.chmod(filename, mod)


 def make_writable(filename):
-    mod = os.stat(filename).st_mode
-    mod = mod | 0200
-    os.chmod(filename, mod)
+    mod = lstat(filename).st_mode
+    if not stat.S_ISLNK(mod):
+        mod = mod | 0200
+        os.chmod(filename, mod)


 _QUOTE_RE = None

-- 
Elliot Murphy | https://launchpad.net/~emurphy/