Add set_git_dir() function

With the function set_git_dir() you can reset the path that will
be used for git_path(), git_dir() and friends.

The responsibility to close files and throw away information from the
old git_dir lies with the caller.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/environment.c b/environment.c
index f83fb9e448..a571fae607 100644
--- a/environment.c
+++ b/environment.c
@@ -107,3 +107,11 @@ char *get_graft_file(void)
 		setup_git_env();
 	return git_graft_file;
 }
+
+int set_git_dir(const char *path)
+{
+	if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
+		return error("Could not set GIT_DIR to '%s'", path);
+	setup_git_env();
+	return 0;
+}