[PATCH v2 11/16] {fetch,upload}-pack: support fetching from a shallow clone via smart http

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 Documentation/technical/pack-protocol.txt |  3 +++
 builtin/fetch-pack.c                      |  3 +--
 remote-curl.c                             |  4 +++-
 t/t5536-fetch-shallow.sh                  | 27 +++++++++++++++++++++++++++
 upload-pack.c                             |  2 --
 5 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index a1672bc..5013652 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -574,6 +574,7 @@ respectively. The output is in pkt-line format.
   advertised-refs  =  service
 		      flush-pkt
 		      (no-refs / list-of-refs)
+		      *shallow
 		      flush-pkt
 
   service          =  PKT-LINE("# service=" service-name)
@@ -590,6 +591,8 @@ respectively. The output is in pkt-line format.
   other-tip        =  obj-id SP refname LF
   other-peeled     =  obj-id SP refname "^{}" LF
 
+  shallow           =  PKT-LINE("shallow" SP obj-id)
+
   capability-list  =  capability *(SP capability)
   capability       =  1*(LC_ALPHA / DIGIT / "-" / "_")
   LC_ALPHA         =  %x61-7A
diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
index f6a6d76..b89d753 100644
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@ -146,8 +146,7 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 	}
 
 	memset(&shallow, 0, sizeof(shallow));
-	get_remote_heads(fd[0], NULL, 0, &ref, 0, NULL,
-			 args.stateless_rpc ? NULL : &shallow);
+	get_remote_heads(fd[0], NULL, 0, &ref, 0, NULL, &shallow);
 
 	ref = fetch_pack(&args, fd, conn, ref, dest,
 			 sought, nr_sought, &shallow, pack_lockfile_ptr);
diff --git a/remote-curl.c b/remote-curl.c
index c329bd3..de2cc8a 100644
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -78,6 +78,7 @@ struct discovery {
 	char *buf;
 	size_t len;
 	struct ref *refs;
+	struct extra_have_objects shallow;
 	unsigned proto_git : 1;
 };
 static struct discovery *last_discovery;
@@ -86,7 +87,7 @@ static struct ref *parse_git_refs(struct discovery *heads, int for_push)
 {
 	struct ref *list = NULL;
 	get_remote_heads(-1, heads->buf, heads->len, &list,
-			 for_push ? REF_NORMAL : 0, NULL, NULL);
+			 for_push ? REF_NORMAL : 0, NULL, &heads->shallow);
 	return list;
 }
 
@@ -146,6 +147,7 @@ static void free_discovery(struct discovery *d)
 	if (d) {
 		if (d == last_discovery)
 			last_discovery = NULL;
+		free(d->shallow.array);
 		free(d->buf_alloc);
 		free_refs(d->refs);
 		free(d);
diff --git a/t/t5536-fetch-shallow.sh b/t/t5536-fetch-shallow.sh
index 15a8208..6ea6347 100755
--- a/t/t5536-fetch-shallow.sh
+++ b/t/t5536-fetch-shallow.sh
@@ -102,4 +102,31 @@ EOF
 
 '
 
+if test -n "$NO_CURL" -o -z "$GIT_TEST_HTTPD"; then
+	say 'skipping remaining tests, git built without http support'
+	test_done
+fi
+
+LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5536'}
+. "$TEST_DIRECTORY"/lib-httpd.sh
+start_httpd
+
+test_expect_success 'clone http repository' '
+	git clone --bare --no-local shallow "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" &&
+	git clone --quiet $HTTPD_URL/smart/repo.git clone &&
+	(
+	cd clone &&
+	git fsck &&
+	git log --format=%s origin/master >actual &&
+	cat <<EOF >expect &&
+6
+5
+4
+3
+EOF
+	test_cmp expect actual
+	)
+'
+
+stop_httpd
 test_done
diff --git a/upload-pack.c b/upload-pack.c
index c3e68ae..263ae08 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -770,8 +770,6 @@ int main(int argc, char **argv)
 
 	if (!enter_repo(dir, strict))
 		die("'%s' does not appear to be a git repository", dir);
-	if (is_repository_shallow() && stateless_rpc)
-		die("attempt to push into a shallow repository");
 
 	git_config(upload_pack_config, NULL);
 	upload_pack();
-- 
1.8.2.83.gc99314b