[PATCH] Fix backwards-incompatible handling of core.sharedRepository

[Petr Baudis <pasky@suse.cz>]

The 06cbe8550324e0fd2290839bf3b9a92aa53b70ab core.sharedRepository
handling extension broke backwards compatibility; before, shared=1 meant
that Git merely ensured the repository is group-writable, not that it's
_only_ group-writable, which is the current behaviour.

Maybe it makes sense to provide the current semantics in some way too,
but that cannot be done at the expense of ditching backwards
compatibility; this bug has just wasted me two hours and broke
repo.or.cz pushing for several hours.

Signed-off-by: Petr Baudis <pasky@rover.dkm.cz>
---

 Sorry for the resend, StGIT kind of tricked me to adding two Cc headers and
 the first one just got dropped.

 path.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)


diff --git a/path.c b/path.c
index 5983255..75c5915 100644
--- a/path.c
+++ b/path.c
@@ -269,7 +269,7 @@ int adjust_shared_perm(const char *path)
 	mode = st.st_mode;
 
 	if (shared_repository) {
-		int tweak = shared_repository;
+		int tweak = (mode & 0777) | shared_repository;
 		if (!(mode & S_IWUSR))
 			tweak &= ~0222;
 		mode = (mode & ~0777) | tweak;