builtin/update-index: convert to using the_hash_algo

Switch from using GIT_SHA1_HEXSZ to the_hash_algo to make the parsing of
the index information hash independent.
Signed-off-by: Nbrian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin/update-index.c

@@ -492,6 +492,7 @@ static void update_one(const char *path)
 
 static void read_index_info(int nul_term_line)
 {
+	const int hexsz = the_hash_algo->hexsz;
 	struct strbuf buf = STRBUF_INIT;
 	struct strbuf uq = STRBUF_INIT;
 	strbuf_getline_fn getline_fn;
@@ -529,7 +530,7 @@ static void read_index_info(int nul_term_line)
 		mode = ul;
 
 		tab = strchr(ptr, '\t');
-		if (!tab || tab - ptr < GIT_SHA1_HEXSZ + 1)
+		if (!tab || tab - ptr < hexsz + 1)
 			goto bad_line;
 
 		if (tab[-2] == ' ' && '0' <= tab[-1] && tab[-1] <= '3') {
@@ -542,8 +543,8 @@ static void read_index_info(int nul_term_line)
 			ptr = tab + 1; /* point at the head of path */
 		}
 
-		if (get_oid_hex(tab - GIT_SHA1_HEXSZ, &oid) ||
-			tab[-(GIT_SHA1_HEXSZ + 1)] != ' ')
+		if (get_oid_hex(tab - hexsz, &oid) ||
+			tab[-(hexsz + 1)] != ' ')
 			goto bad_line;
 
 		path_name = ptr;
@@ -571,7 +572,7 @@ static void read_index_info(int nul_term_line)
 			 * ptr[-1] points at tab,
 			 * ptr[-41] is at the beginning of sha1
 			 */
-			ptr[-(GIT_SHA1_HEXSZ + 2)] = ptr[-1] = 0;
+			ptr[-(hexsz + 2)] = ptr[-1] = 0;
 			if (add_cacheinfo(mode, &oid, path_name, stage))
 				die("git update-index: unable to update %s",
 				    path_name);