fetch-pack: Use a strbuf to compose the want list

This change is being offered as a refactoring to make later
commits in the smart HTTP series easier.

By changing the enabled capabilities to be formatted in a strbuf
it is easier to add a new capability to the set of supported
capabilities.

By formatting the want portion of the request into a strbuf and
writing it as a whole block we can later decide to hold onto
the req_buf (instead of releasing it) to recycle in stateless
communications.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 6 deletions

diff --git a/commit.c b/commit.c
index fedbd5e52..471efb056 100644
--- a/commit.c
+++ b/commit.c
@@ -199,7 +199,7 @@ struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
 	return commit_graft[pos];
 }
 
-int write_shallow_commits(int fd, int use_pack_protocol)
+int write_shallow_commits(struct strbuf *out, int use_pack_protocol)
 {
 	int i, count = 0;
 	for (i = 0; i < commit_graft_nr; i++)
@@ -208,12 +208,10 @@ int write_shallow_commits(int fd, int use_pack_protocol)
 				sha1_to_hex(commit_graft[i]->sha1);
 			count++;
 			if (use_pack_protocol)
-				packet_write(fd, "shallow %s", hex);
+				packet_buf_write(out, "shallow %s", hex);
 			else {
-				if (write_in_full(fd, hex,  40) != 40)
-					break;
-				if (write_str_in_full(fd, "\n") != 1)
-					break;
+				strbuf_addstr(out, hex);
+				strbuf_addch(out, '\n');
 			}
 		}
 	return count;