refs: convert read_ref_at to struct object_id

Convert the callers and internals, including struct read_ref_at_cb, of
read_ref_at to use struct object_id.

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

builtin/show-branch.c

@@ -731,7 +731,7 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 				/* Ah, that is a date spec... */
 				timestamp_t at;
 				at = approxidate(reflog_base);
-				read_ref_at(ref, flags, at, -1, oid.hash, NULL,
+				read_ref_at(ref, flags, at, -1, &oid, NULL,
 					    NULL, NULL, &base);
 			}
 		}
@@ -743,7 +743,7 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 			timestamp_t timestamp;
 			int tz;
 
-			if (read_ref_at(ref, flags, 0, base+i, oid.hash, &logmsg,
+			if (read_ref_at(ref, flags, 0, base + i, &oid, &logmsg,
 					&timestamp, &tz, NULL)) {
 				reflog = i;
 				break;

refs.c

@@ -738,11 +738,11 @@ struct read_ref_at_cb {
 	timestamp_t at_time;
 	int cnt;
 	int reccnt;
-	unsigned char *sha1;
+	struct object_id *oid;
 	int found_it;
 
-	unsigned char osha1[20];
-	unsigned char nsha1[20];
+	struct object_id ooid;
+	struct object_id noid;
 	int tz;
 	timestamp_t date;
 	char **msg;
@@ -774,25 +774,25 @@ static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 		 * we have not yet updated cb->[n|o]sha1 so they still
 		 * hold the values for the previous record.
 		 */
-		if (!is_null_sha1(cb->osha1)) {
-			hashcpy(cb->sha1, noid->hash);
-			if (hashcmp(cb->osha1, noid->hash))
+		if (!is_null_oid(&cb->ooid)) {
+			oidcpy(cb->oid, noid);
+			if (oidcmp(&cb->ooid, noid))
 				warning("Log for ref %s has gap after %s.",
 					cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 		}
 		else if (cb->date == cb->at_time)
-			hashcpy(cb->sha1, noid->hash);
-		else if (hashcmp(noid->hash, cb->sha1))
+			oidcpy(cb->oid, noid);
+		else if (oidcmp(noid, cb->oid))
 			warning("Log for ref %s unexpectedly ended on %s.",
 				cb->refname, show_date(cb->date, cb->tz,
 						       DATE_MODE(RFC2822)));
-		hashcpy(cb->osha1, ooid->hash);
-		hashcpy(cb->nsha1, noid->hash);
+		oidcpy(&cb->ooid, ooid);
+		oidcpy(&cb->noid, noid);
 		cb->found_it = 1;
 		return 1;
 	}
-	hashcpy(cb->osha1, ooid->hash);
-	hashcpy(cb->nsha1, noid->hash);
+	oidcpy(&cb->ooid, ooid);
+	oidcpy(&cb->noid, noid);
 	if (cb->cnt > 0)
 		cb->cnt--;
 	return 0;
@@ -812,15 +812,15 @@ static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid
 		*cb->cutoff_tz = tz;
 	if (cb->cutoff_cnt)
 		*cb->cutoff_cnt = cb->reccnt;
-	hashcpy(cb->sha1, ooid->hash);
-	if (is_null_sha1(cb->sha1))
-		hashcpy(cb->sha1, noid->hash);
+	oidcpy(cb->oid, ooid);
+	if (is_null_oid(cb->oid))
+		oidcpy(cb->oid, noid);
 	/* We just want the first entry */
 	return 1;
 }
 
 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
-		unsigned char *sha1, char **msg,
+		struct object_id *oid, char **msg,
 		timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 {
 	struct read_ref_at_cb cb;
@@ -833,7 +833,7 @@ int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, in
 	cb.cutoff_time = cutoff_time;
 	cb.cutoff_tz = cutoff_tz;
 	cb.cutoff_cnt = cutoff_cnt;
-	cb.sha1 = sha1;
+	cb.oid = oid;
 
 	for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
 

refs.h

@@ -363,7 +363,7 @@ int safe_create_reflog(const char *refname, int force_create, struct strbuf *err
 /** Reads log for the value of ref during at_time. **/
 int read_ref_at(const char *refname, unsigned int flags,
 		timestamp_t at_time, int cnt,
-		unsigned char *sha1, char **msg,
+		struct object_id *oid, char **msg,
 		timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
 
 /** Check if a particular reflog exists */

sha1_name.c

@@ -697,7 +697,7 @@ static int get_oid_basic(const char *str, int len, struct object_id *oid,
 				return -1;
 			}
 		}
-		if (read_ref_at(real_ref, flags, at_time, nth, oid->hash, NULL,
+		if (read_ref_at(real_ref, flags, at_time, nth, oid, NULL,
 				&co_time, &co_tz, &co_cnt)) {
 			if (!len) {
 				if (starts_with(real_ref, "refs/heads/")) {