refspec: consolidate ref-prefix generation logic

When using protocol v2 a client constructs a list of ref-prefixes which
are sent across the wire so that the server can do server-side filtering
of the ref-advertisement.  The logic that does this exists for both
fetch and push (even though no push support for v2 currently exists yet)
and is roughly the same so lets consolidate this logic and make it
general enough that it can be used for both the push and fetch cases.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

4 files changed, 35 insertions, 32 deletions

diff --git a/builtin/fetch.c b/builtin/fetch.c
index 3fad1f0db9..80bb143707 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -351,18 +351,7 @@ static struct ref *get_ref_map(struct transport *transport,
 
 	const struct ref *remote_refs;
 
-	for (i = 0; i < rs->nr; i++) {
-		const struct refspec_item *item = &rs->items[i];
-		if (!item->exact_sha1) {
-			const char *glob = strchr(item->src, '*');
-			if (glob)
-				argv_array_pushf(&ref_prefixes, "%.*s",
-						 (int)(glob - item->src),
-						 item->src);
-			else
-				expand_ref_prefix(&ref_prefixes, item->src);
-		}
-	}
+	refspec_ref_prefixes(rs, &ref_prefixes);
 
 	remote_refs = transport_get_remote_refs(transport, &ref_prefixes);
 
diff --git a/refspec.c b/refspec.c
index 97e76e8b1d..c59a4ccf1e 100644
--- a/refspec.c
+++ b/refspec.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "argv-array.h"
 #include "refs.h"
 #include "refspec.h"
 
@@ -192,3 +193,31 @@ int valid_fetch_refspec(const char *fetch_refspec_str)
 	refspec_item_clear(&refspec);
 	return ret;
 }
+
+void refspec_ref_prefixes(const struct refspec *rs,
+			  struct argv_array *ref_prefixes)
+{
+	int i;
+	for (i = 0; i < rs->nr; i++) {
+		const struct refspec_item *item = &rs->items[i];
+		const char *prefix = NULL;
+
+		if (rs->fetch == REFSPEC_FETCH)
+			prefix = item->src;
+		else if (item->dst)
+			prefix = item->dst;
+		else if (item->src && !item->exact_sha1)
+			prefix = item->src;
+
+		if (prefix) {
+			if (item->pattern) {
+				const char *glob = strchr(prefix, '*');
+				argv_array_pushf(ref_prefixes, "%.*s",
+						 (int)(glob - prefix),
+						 prefix);
+			} else {
+				expand_ref_prefix(ref_prefixes, prefix);
+			}
+		}
+	}
+}
diff --git a/refspec.h b/refspec.h
index 7e1ff94ac9..01b700e094 100644
--- a/refspec.h
+++ b/refspec.h
@@ -41,4 +41,8 @@ void refspec_clear(struct refspec *rs);
 
 int valid_fetch_refspec(const char *refspec);
 
+struct argv_array;
+void refspec_ref_prefixes(const struct refspec *rs,
+			  struct argv_array *ref_prefixes);
+
 #endif /* REFSPEC_H */
diff --git a/transport.c b/transport.c
index 7e0b9abba3..cbf0044c3e 100644
--- a/transport.c
+++ b/transport.c
@@ -1088,30 +1088,11 @@ int transport_push(struct transport *transport,
 		int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
 		int push_ret, ret, err;
 		struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
-		int i;
 
 		if (check_push_refs(local_refs, rs) < 0)
 			return -1;
 
-		for (i = 0; i < rs->nr; i++) {
-			const struct refspec_item *item = &rs->items[i];
-			const char *prefix = NULL;
-
-			if (item->dst)
-				prefix = item->dst;
-			else if (item->src && !item->exact_sha1)
-				prefix = item->src;
-
-			if (prefix) {
-				const char *glob = strchr(prefix, '*');
-				if (glob)
-					argv_array_pushf(&ref_prefixes, "%.*s",
-							 (int)(glob - prefix),
-							 prefix);
-				else
-					expand_ref_prefix(&ref_prefixes, prefix);
-			}
-		}
+		refspec_ref_prefixes(rs, &ref_prefixes);
 
 		remote_refs = transport->vtable->get_refs_list(transport, 1,
 							       &ref_prefixes);