upload-pack: send shallow info over stdin to pack-objects

Before cdab485 (upload-pack: delegate rev walking in shallow fetch to
pack-objects - 2013-08-16) upload-pack does not write to the source
repository. cdab485 starts to write $GIT_DIR/shallow_XXXXXX if it's a
shallow fetch, so the source repo must be writable.

git:// servers do not need write access to repos and usually don't
have it, which means cdab485 breaks shallow clone over git://

Instead of using a temporary file as the media for shallow points, we
can send them over stdin to pack-objects as well. Prepend shallow
SHA-1 with --shallow so pack-objects knows what is what.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 12 insertions, 9 deletions

diff --git a/upload-pack.c b/upload-pack.c
index 0c44f6b29..a5c50e4ce 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -70,6 +70,14 @@ static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
 	return sz;
 }
 
+static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
+{
+	FILE *fp = cb_data;
+	if (graft->nr_parent == -1)
+		fprintf(fp, "--shallow %s\n", sha1_to_hex(graft->sha1));
+	return 0;
+}
+
 static void create_pack_file(void)
 {
 	struct child_process pack_objects;
@@ -81,12 +89,10 @@ static void create_pack_file(void)
 	const char *argv[12];
 	int i, arg = 0;
 	FILE *pipe_fd;
-	char *shallow_file = NULL;
 
 	if (shallow_nr) {
-		shallow_file = setup_temporary_shallow(NULL);
 		argv[arg++] = "--shallow-file";
-		argv[arg++] = shallow_file;
+		argv[arg++] = "";
 	}
 	argv[arg++] = "pack-objects";
 	argv[arg++] = "--revs";
@@ -114,6 +120,9 @@ static void create_pack_file(void)
 
 	pipe_fd = xfdopen(pack_objects.in, "w");
 
+	if (shallow_nr)
+		for_each_commit_graft(write_one_shallow, pipe_fd);
+
 	for (i = 0; i < want_obj.nr; i++)
 		fprintf(pipe_fd, "%s\n",
 			sha1_to_hex(want_obj.objects[i].item->sha1));
@@ -242,12 +251,6 @@ static void create_pack_file(void)
 		error("git upload-pack: git-pack-objects died with error.");
 		goto fail;
 	}
-	if (shallow_file) {
-		if (*shallow_file)
-			unlink(shallow_file);
-		free(shallow_file);
-	}
-
 	/* flush the data */
 	if (0 <= buffered) {
 		data[0] = buffered;