pkt-line: add a member for hash algorithm

Add a member for the hash algorithm currently in use to the packet
reader so it can parse references correctly.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/pkt-line.c b/pkt-line.c
index a0e87b1..a4aea07 100644
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -479,6 +479,7 @@ void packet_reader_init(struct packet_reader *reader, int fd,
 	reader->buffer_size = sizeof(packet_buffer);
 	reader->options = options;
 	reader->me = "git";
+	reader->hash_algo = &hash_algos[GIT_HASH_SHA1];
 }
 
 enum packet_read_status packet_reader_read(struct packet_reader *reader)
diff --git a/pkt-line.h b/pkt-line.h
index fef3a0d..4cd9435 100644
--- a/pkt-line.h
+++ b/pkt-line.h
@@ -166,6 +166,9 @@ struct packet_reader {
 
 	unsigned use_sideband : 1;
 	const char *me;
+
+	/* hash algorithm in use */
+	const struct git_hash_algo *hash_algo;
 };
 
 /*