Introduce GIT_DIR environment variable.

During the mailing list discussion on renaming GIT_ environment
variables, people felt that having one environment that lets the
user (or Porcelain) specify both SHA1_FILE_DIRECTORY (now
GIT_OBJECT_DIRECTORY) and GIT_INDEX_FILE for the default layout
would be handy.  This change introduces GIT_DIR environment
variable, from which the defaults for GIT_INDEX_FILE and
GIT_OBJECT_DIRECTORY are derived.  When GIT_DIR is not defined,
it defaults to ".git".  GIT_INDEX_FILE defaults to
"$GIT_DIR/index" and GIT_OBJECT_DIRECTORY defaults to
"$GIT_DIR/objects".

Special thanks for ideas and discussions go to Petr Baudis and
Daniel Barkalow.  Bugs are mine ;-)

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 6 insertions, 5 deletions

diff --git a/init-db.c b/init-db.c
index 157b92b..b6bb783 100644
--- a/init-db.c
+++ b/init-db.c
@@ -27,11 +27,12 @@ int main(int argc, char **argv)
 	char *path;
 	int len, i;
 
-	safe_create_dir(".git");
-
-	sha1_dir = gitenv(DB_ENVIRONMENT);
-	if (!sha1_dir) {
-		sha1_dir = DEFAULT_DB_ENVIRONMENT;
+	sha1_dir = get_object_directory();
+	if (!gitenv(DB_ENVIRONMENT) && !gitenv(GIT_DIR_ENVIRONMENT)) {
+		/* We create leading paths only when we fall back
+		 * to local .git/objects, at least for now.
+		 */
+		safe_create_dir(DEFAULT_GIT_DIR_ENVIRONMENT);
 		fprintf(stderr, "defaulting to local storage area\n");
 	}
 	len = strlen(sha1_dir);