[PATCH 09/14] fetch-pack: Add negotiate_capabilities

[Stefan Beller <sbeller@google.com>]

As in the pack protocol version 2 we want to
negotiate the capabilities before any other exchange
we will have a function which will take care of the
whole negotiation process.

It will be placed in fetch-pack.c for now as there
we have access to its internal variables and we'll
work on a `struct fetch_pack_args`. Eventually we
want to move it to a better place such as transport.c

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 fetch-pack.c | 14 ++++++++++++++
 fetch-pack.h |  6 ++++++
 2 files changed, 20 insertions(+)

diff --git a/fetch-pack.c b/fetch-pack.c
index b43490f..1544629 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -888,6 +888,20 @@ static void get_selected_capabilities_list(struct string_list *list,
 	}
 }
 
+void negotiate_capabilities(int fd[2], struct fetch_pack_args *args)
+{
+	struct string_list list = STRING_LIST_INIT_NODUP;
+
+	get_remote_capabilities(fd[0], NULL, 0);
+
+	select_capabilities(args);
+	get_selected_capabilities_list(&list, args);
+
+	request_capabilities(fd[1], &list);
+
+	string_list_clear(&list, 1);
+}
+
 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 				 int fd[2],
 				 const struct ref *orig_ref,
diff --git a/fetch-pack.h b/fetch-pack.h
index 3314362..198498a 100644
--- a/fetch-pack.h
+++ b/fetch-pack.h
@@ -29,6 +29,12 @@ struct fetch_pack_args {
 };
 
 /*
+ * In version 2 of the pack protocol we negotiate the capabilities
+ * before the actual transfer of refs and packs.
+ */
+void negotiate_capabilities(int fd[2], struct fetch_pack_args *args);
+
+/*
  * sought represents remote references that should be updated from.
  * On return, the names that were found on the remote will have been
  * marked as such.
-- 
2.8.0.32.g71f8beb.dirty