Subject: Re: [RFC PATCH] Fix gitdir detection when in subdir of gitdir

From: SZEDER Gábor <[email-masked]>
Date: Mon, 19 Jan 2009 03:03:11 +0100

On Sun, Jan 18, 2009 at 01:27:44PM -0800, Junio C Hamano wrote:
> Junio C Hamano <[email-masked]> writes:
> 
> > I think (1) the solution (almost) makes sense, (2) the patch needs to be
> > explained a lot better as you mentioned in your two messages, and (3) if
> > it does not affect any other case than when you are in a subdirectory of
> > the .git/ directory, then you are doing something funny anyway and
> > performance issue Dscho mentions, if any, is not a concern.
> >
> > My "(almost)" in (1) above is because the patch uses this new behaviour
> > even when you are inside the .git/ directory itself (or at the root of a
> > bare repository), which is a very common case that we do not have to nor
> > want to change the behaviour.  It also invalidates the precondition of (3)
> > above.
> 
> And this is a trivial follow-up on top of Szeder's patch.

Thanks.  In the meantime I was working on a patch that sets relative
path in this case, too.  I got it almost working: all tests passed
except '.git/objects/: is-bare-repository' in 't1500-rev-parse'.  I
couldn't figure it out why this test failed, however.

In case somebody might be interested for such an uncommon case, the
patch is below.

Best,
Gábor

 setup.c |   17 +++++++++++++++--
 1 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/setup.c b/setup.c
index 6b277b6..b4d37d7 100644
--- a/setup.c
+++ b/setup.c
@@ -375,7 +375,7 @@ const char *setup_git_directory_gently(int *nongit_ok)
 	static char cwd[PATH_MAX+1];
 	const char *gitdirenv;
 	const char *gitfile_dir;
-	int len, offset, ceil_offset;
+	int len, offset, ceil_offset, cdup_count = 0;
 
 	/*
 	 * Let's assume that we are in a git repository.
@@ -453,10 +453,22 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 			break;
 		if (is_git_directory(".")) {
+			char gd_rel_path[PATH_MAX];
 			inside_git_dir = 1;
 			if (!work_tree_env)
 				inside_work_tree = 0;
-			setenv(GIT_DIR_ENVIRONMENT, ".", 1);
+			if (cdup_count) {
+				char *p = gd_rel_path;
+				while (cdup_count-- > 1) {
+					*p++ = '.'; *p++ = '.'; *p++ = '/';
+				}
+				*p++ = '.'; *p++ = '.';
+				*p = '\0';
+			} else {
+				gd_rel_path[0] = '.';
+				gd_rel_path[1] = '\0';
+			}
+			setenv(GIT_DIR_ENVIRONMENT, gd_rel_path, 1);
 			check_repository_format_gently(nongit_ok);
 			return NULL;
 		}
@@ -472,6 +484,7 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		}
 		if (chdir(".."))
 			die("Cannot change to %s/..: %s", cwd, strerror(errno));
+		cdup_count++;
 	}
 
 	inside_git_dir = 0;