Add for_each_remote() function, and extend remote_find_tracking()

The function for_each_remote() does exactly what the name
suggests.

The function remote_find_tracking() was extended to be able to
search remote refs for a given local ref.  The caller sets
either src or dst (but not both) in the refspec parameter, and
remote_find_tracking() will fill in the other and return 0.

Both changes are required for the next step: simplification of
git-branch's --track functionality.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 51 insertions, 18 deletions

diff --git a/remote.c b/remote.c
index 09c427906d..bb774d0bcc 100644
--- a/remote.c
+++ b/remote.c
@@ -279,6 +279,25 @@ struct remote *remote_get(const char *name)
 	return ret;
 }
 
+int for_each_remote(each_remote_fn fn, void *priv)
+{
+	int i, result = 0;
+	read_config();
+	for (i = 0; i < allocated_remotes && !result; i++) {
+		struct remote *r = remotes[i];
+		if (!r)
+			continue;
+		if (!r->fetch)
+			r->fetch = parse_ref_spec(r->fetch_refspec_nr,
+					r->fetch_refspec);
+		if (!r->push)
+			r->push = parse_ref_spec(r->push_refspec_nr,
+					r->push_refspec);
+		result = fn(r, priv);
+	}
+	return result;
+}
+
 int remote_has_uri(struct remote *remote, const char *uri)
 {
 	int i;
@@ -291,32 +310,43 @@ int remote_has_uri(struct remote *remote, const char *uri)
 
 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 {
+	int find_src = refspec->src == NULL;
+	char *needle, **result;
 	int i;
+
+	if (find_src) {
+		if (refspec->dst == NULL)
+			return error("find_tracking: need either src or dst");
+		needle = refspec->dst;
+		result = &refspec->src;
+	} else {
+		needle = refspec->src;
+		result = &refspec->dst;
+	}
+
 	for (i = 0; i < remote->fetch_refspec_nr; i++) {
 		struct refspec *fetch = &remote->fetch[i];
+		const char *key = find_src ? fetch->dst : fetch->src;
+		const char *value = find_src ? fetch->src : fetch->dst;
 		if (!fetch->dst)
 			continue;
 		if (fetch->pattern) {
-			if (!prefixcmp(refspec->src, fetch->src)) {
-				refspec->dst =
-					xmalloc(strlen(fetch->dst) +
-						strlen(refspec->src) -
-						strlen(fetch->src) + 1);
-				strcpy(refspec->dst, fetch->dst);
-				strcpy(refspec->dst + strlen(fetch->dst),
-				       refspec->src + strlen(fetch->src));
-				refspec->force = fetch->force;
-				return 0;
-			}
-		} else {
-			if (!strcmp(refspec->src, fetch->src)) {
-				refspec->dst = xstrdup(fetch->dst);
+			if (!prefixcmp(needle, key)) {
+				*result = xmalloc(strlen(value) +
+						  strlen(needle) -
+						  strlen(key) + 1);
+				strcpy(*result, value);
+				strcpy(*result + strlen(value),
+				       needle + strlen(key));
 				refspec->force = fetch->force;
 				return 0;
 			}
+		} else if (!strcmp(needle, key)) {
+			*result = xstrdup(value);
+			refspec->force = fetch->force;
+			return 0;
 		}
 	}
-	refspec->dst = NULL;
 	return -1;
 }
 
diff --git a/remote.h b/remote.h
index 080b7dab99..17b8b5b5d5 100644
--- a/remote.h
+++ b/remote.h
@@ -20,13 +20,16 @@ struct remote {
 
 struct remote *remote_get(const char *name);
 
+typedef int each_remote_fn(struct remote *remote, void *priv);
+int for_each_remote(each_remote_fn fn, void *priv);
+
 int remote_has_uri(struct remote *remote, const char *uri);
 
 struct refspec {
 	unsigned force : 1;
 	unsigned pattern : 1;
 
-	const char *src;
+	char *src;
 	char *dst;
 };
 
diff --git a/send-pack.c b/send-pack.c
index fecbda981b..9fc8a812f4 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -305,8 +305,8 @@ static int send_pack(int in, int out, struct remote *remote, int nr_refspec, cha
 		if (remote) {
 			struct refspec rs;
 			rs.src = ref->name;
-			remote_find_tracking(remote, &rs);
-			if (rs.dst) {
+			rs.dst = NULL;
+			if (!remote_find_tracking(remote, &rs)) {
 				struct ref_lock *lock;
 				fprintf(stderr, " Also local %s\n", rs.dst);
 				if (will_delete_ref) {