hex: introduce parsing variants taking hash algorithms

Introduce variants of get_oid_hex and parse_oid_hex that parse an
arbitrary hash algorithm, implementing internal functions to avoid
duplication.  These functions can be used in the transport code to parse
refs properly.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 26 insertions, 7 deletions

diff --git a/hex.c b/hex.c
index fd7f00c43f..10e24dc2e4 100644
--- a/hex.c
+++ b/hex.c
@@ -47,32 +47,51 @@ int hex_to_bytes(unsigned char *binary, const char *hex, size_t len)
 	return 0;
 }
 
-int get_sha1_hex(const char *hex, unsigned char *sha1)
+static int get_hash_hex_algop(const char *hex, unsigned char *hash,
+			      const struct git_hash_algo *algop)
 {
 	int i;
-	for (i = 0; i < the_hash_algo->rawsz; i++) {
+	for (i = 0; i < algop->rawsz; i++) {
 		int val = hex2chr(hex);
 		if (val < 0)
 			return -1;
-		*sha1++ = val;
+		*hash++ = val;
 		hex += 2;
 	}
 	return 0;
 }
 
+int get_sha1_hex(const char *hex, unsigned char *sha1)
+{
+	return get_hash_hex_algop(hex, sha1, the_hash_algo);
+}
+
+int get_oid_hex_algop(const char *hex, struct object_id *oid,
+		      const struct git_hash_algo *algop)
+{
+	return get_hash_hex_algop(hex, oid->hash, algop);
+}
+
 int get_oid_hex(const char *hex, struct object_id *oid)
 {
-	return get_sha1_hex(hex, oid->hash);
+	return get_oid_hex_algop(hex, oid, the_hash_algo);
 }
 
-int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
+int parse_oid_hex_algop(const char *hex, struct object_id *oid,
+			const char **end,
+			const struct git_hash_algo *algop)
 {
-	int ret = get_oid_hex(hex, oid);
+	int ret = get_hash_hex_algop(hex, oid->hash, algop);
 	if (!ret)
-		*end = hex + the_hash_algo->hexsz;
+		*end = hex + algop->hexsz;
 	return ret;
 }
 
+int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
+{
+	return parse_oid_hex_algop(hex, oid, end, the_hash_algo);
+}
+
 char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
 			  const struct git_hash_algo *algop)
 {