Re: [PATCH] Make Git accept absolute path names for files within the work tree

From: Jeff King <peff@peff.net>
Date: Dec 4, 2007, 22:08 UTC
Message-ID: <20071204220840.GA3340@coredump.intra.peff.net>
In-Reply-To: <alpine.LFD.0.9999.0712040756370.2981@woody.linux-foundation.org>

On Tue, Dec 04, 2007 at 07:59:43AM -0800, Linus Torvalds wrote:

Show 6 quoted lines

> > I do remember the hassles I went through with get_relative_cwd() until I 
> > broke down and used chdir() two times (ugly).
> 
> It really is a pretty heavy and complex operation in UNIX in general (and 
> open to various races too), which is why I'd generally suggest avoiding it 
> if you at all can.

It is more expensive, though we will be doing it once per user-supplied pathspec, so I don't know that it will actually have an impact.

I am concerned that not supporting symlinks will make this feature unusably annoying for some users. I used to have a home directory that had a symlink in it, and I frequently ran into these sorts of path comparison issues ($HOME was /home/peff, so typing ~/repo/file pointed there, but /home was a symlink to /mnt/data/home, so any routines that normalize the cwd used /mnt/data/home/repo, and the two never matched up).

Hrm. Looks like somebody has already helpfully implemented make_absolute_path, so it would just require calling that on each argument. Something like this on top of Robin's patch:

diff --git a/setup.c b/setup.c
index 4ee8024..e76c83c 100644
--- a/setup.c
+++ b/setup.c
@@ -58,7 +58,8 @@ const char *prefix_path(const char *prefix, int len, const char *path)
 {
 	const char *orig = path;
 	if (is_absolute_path(path))
-		path = strip_work_tree_path(prefix, len, path);
+		path = strip_work_tree_path(prefix, len,
+				xstrdup(make_absolute_path(path)));
 
 	for (;;) {
 		char c;

-Peff