pack-objects: reuse on-disk deltas for thin "have" objects

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 0d80dee2ba1ad82fd21622f73dac86b6010da4b6..1bd43432f7789a60e39d5b45f5370f001279b050 100644 (file)
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -40,6 +40,7 @@
 #define DELTA_CHILD(obj) oe_delta_child(&to_pack, obj)
 #define DELTA_SIBLING(obj) oe_delta_sibling(&to_pack, obj)
 #define SET_DELTA(obj, val) oe_set_delta(&to_pack, obj, val)
+#define SET_DELTA_EXT(obj, oid) oe_set_delta_ext(&to_pack, obj, oid)
 #define SET_DELTA_SIZE(obj, val) oe_set_delta_size(&to_pack, obj, val)
 #define SET_DELTA_CHILD(obj, val) oe_set_delta_child(&to_pack, obj, val)
 #define SET_DELTA_SIBLING(obj, val) oe_set_delta_sibling(&to_pack, obj, val)
@@ -59,6 +60,7 @@ static struct packing_data to_pack;
 
 static struct pack_idx_entry **written_list;
 static uint32_t nr_result, nr_written, nr_seen;
+static struct bitmap_index *bitmap_git;
 
 static int non_empty;
 static int reuse_delta = 1, reuse_object = 1;
@@ -79,6 +81,7 @@ static unsigned long pack_size_limit;
 static int depth = 50;
 static int delta_search_threads;
 static int pack_to_stdout;
+static int thin;
 static int num_preferred_base;
 static struct progress *progress_state;
 
@@ -1510,11 +1513,15 @@ static void check_object(struct object_entry *entry)
                        break;
                }
 
-               if (base_ref && (base_entry = packlist_find(&to_pack, base_ref, NULL))) {
+               if (base_ref && (
+                   (base_entry = packlist_find(&to_pack, base_ref, NULL)) ||
+                   (thin &&
+                    bitmap_has_sha1_in_uninteresting(bitmap_git, base_ref)))) {
                        /*
                         * If base_ref was set above that means we wish to
-                        * reuse delta data, and we even found that base
-                        * in the list of objects we want to pack. Goodie!
+                        * reuse delta data, and either we found that object in
+                        * the list of objects we want to pack, or it's one we
+                        * know the receiver has.
                         *
                         * Depth value does not matter - find_deltas() will
                         * never consider reused delta as the base object to
@@ -1523,10 +1530,16 @@ static void check_object(struct object_entry *entry)
                         */
                        oe_set_type(entry, entry->in_pack_type);
                        SET_SIZE(entry, in_pack_size); /* delta size */
-                       SET_DELTA(entry, base_entry);
                        SET_DELTA_SIZE(entry, in_pack_size);
-                       entry->delta_sibling_idx = base_entry->delta_child_idx;
-                       SET_DELTA_CHILD(base_entry, entry);
+
+                       if (base_entry) {
+                               SET_DELTA(entry, base_entry);
+                               entry->delta_sibling_idx = base_entry->delta_child_idx;
+                               SET_DELTA_CHILD(base_entry, entry);
+                       } else {
+                               SET_DELTA_EXT(entry, base_ref);
+                       }
+
                        unuse_pack(&w_curs);
                        return;
                }
@@ -2954,7 +2967,6 @@ static int pack_options_allow_reuse(void)
 
 static int get_object_list_from_bitmap(struct rev_info *revs)
 {
-       struct bitmap_index *bitmap_git;
        if (!(bitmap_git = prepare_bitmap_walk(revs)))
                return -1;
 
@@ -2970,7 +2982,6 @@ static int get_object_list_from_bitmap(struct rev_info *revs)
        }
 
        traverse_bitmap_commit_list(bitmap_git, &add_object_entry_from_bitmap);
-       free_bitmap_index(bitmap_git);
        return 0;
 }
 
@@ -3118,7 +3129,6 @@ static int option_parse_unpack_unreachable(const struct option *opt,
 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 {
        int use_internal_rev_list = 0;
-       int thin = 0;
        int shallow = 0;
        int all_progress_implied = 0;
        struct argv_array rp = ARGV_ARRAY_INIT;