upload-pack: refactor ok_to_give_up()

In anticipation of consolidating all commit reachability algorithms,
refactor ok_to_give_up() in order to allow splitting its logic into
an external method.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/upload-pack.c b/upload-pack.c
index 5a639cb47b82bd73ddb1ecbcb2f676ada8f545be..9fe19003c6b7f511c2fcb3b5280c3c823dc33eaa 100644 (file)
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -369,34 +369,46 @@ static int reachable(struct commit *from, unsigned int with_flag,
        return (from->object.flags & assign_flag);
 }
 
        return (from->object.flags & assign_flag);
 }
 

-static int ok_to_give_up(void)
+/*
+ * Determine if every commit in 'from' can reach at least one commit
+ * that is marked with 'with_flag'. As we traverse, use 'assign_flag'
+ * as a marker for commits that are already visited.
+ */
+static int can_all_from_reach_with_flag(struct object_array *from,
+                                       unsigned int with_flag,
+                                       unsigned int assign_flag)

 {
        int i;
 
 {
        int i;
 

-       if (!have_obj.nr)
-               return 0;
-
-       for (i = 0; i < want_obj.nr; i++) {
-               struct object *want = want_obj.objects[i].item;
+       for (i = 0; i < from->nr; i++) {
+               struct object *from_one = from->objects[i].item;

 
 

-               if (want->flags & COMMON_KNOWN)
+               if (from_one->flags & assign_flag)

                        continue;
                        continue;

-               want = deref_tag(the_repository, want, "a want line", 0);
-               if (!want || want->type != OBJ_COMMIT) {
+               from_one = deref_tag(the_repository, from_one, "a from object", 0);
+               if (!from_one || from_one->type != OBJ_COMMIT) {

                        /* no way to tell if this is reachable by
                         * looking at the ancestry chain alone, so
                         * leave a note to ourselves not to worry about
                         * this object anymore.
                         */
                        /* no way to tell if this is reachable by
                         * looking at the ancestry chain alone, so
                         * leave a note to ourselves not to worry about
                         * this object anymore.
                         */

-                       want_obj.objects[i].item->flags |= COMMON_KNOWN;
+                       from->objects[i].item->flags |= assign_flag;

                        continue;
                }
                        continue;
                }

-               if (!reachable((struct commit *)want, THEY_HAVE, COMMON_KNOWN))
+               if (!reachable((struct commit *)from_one, with_flag, assign_flag))

                        return 0;
        }
        return 1;
 }
 
                        return 0;
        }
        return 1;
 }
 

+static int ok_to_give_up(void)
+{
+       if (!have_obj.nr)
+               return 0;
+
+       return can_all_from_reach_with_flag(&want_obj, THEY_HAVE, COMMON_KNOWN);
+}
+

 static int get_common_commits(void)
 {
        struct object_id oid;
 static int get_common_commits(void)
 {
        struct object_id oid;