@matheusbsbs / matheus-bagliano / commits / 30cdc33fba

pack-bitmap: save "have" bitmap from walk

When we do a bitmap walk, we save the result, which represents (WANTs & ~HAVEs); i.e., every object we care about visiting in our walk. However, we throw away the haves bitmap, which can sometimes be useful, too. Save it and provide an access function so code which has performed a walk can query it. A few notes on the accessor interface: - the bitmap code calls these "haves" because it grew out of the want/have negotiation for fetches. But really, these are simply the objects that would be flagged UNINTERESTING in a regular traversal. Let's use that more universal nomenclature for the external module interface. We may want to change the internal naming inside the bitmap code, but that's outside the scope of this patch. - it still uses a bare "sha1" rather than "oid". That's true of all of the bitmap code. And in this particular instance, our caller in pack-objects is dealing with the bare sha1 that comes from a packed REF_DELTA (we're pointing directly to the mmap'd pack on disk). That's something we'll have to deal with as we transition to a new hash, but we can wait and see how the caller ends up being fixed and adjust this interface accordingly. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Aug 21, 2018 at 15:07 UTC 30cdc33fba361528c317042535fad9d5f0a2c6e6

2 files changed +31 -1

pack-bitmap.c

+24 -1

@@ -86,6 +86,9 @@ struct bitmap_index {

86 /* Bitmap result of the last performed walk */

87 struct bitmap *result;

89 + /* "have" bitmap from the last performed walk */

90 + struct bitmap *haves;

91 +

92 /* Version of the bitmap index */

93 unsigned int version;

@@ -759,8 +762,8 @@ struct bitmap_index *prepare_bitmap_walk(struct rev_info *revs)

762 bitmap_and_not(wants_bitmap, haves_bitmap);

763

764 bitmap_git->result = wants_bitmap;

765 + bitmap_git->haves = haves_bitmap;

766

763 - bitmap_free(haves_bitmap);

767 return bitmap_git;

768

769 cleanup:

@@ -1114,5 +1117,25 @@ void free_bitmap_index(struct bitmap_index *b)

1117 free(b->ext_index.objects);

1118 free(b->ext_index.hashes);

1119 bitmap_free(b->result);

1120 + bitmap_free(b->haves);

1121 free(b);

1122 }

1123 +

1124 +int bitmap_has_sha1_in_uninteresting(struct bitmap_index *bitmap_git,

1125 + const unsigned char *sha1)

1126 +{

1127 + int pos;

1128 +

1129 + if (!bitmap_git)

1130 + return 0; /* no bitmap loaded */

1131 + if (!bitmap_git->result)

1132 + BUG("failed to perform bitmap walk before querying");

1133 + if (!bitmap_git->haves)

1134 + return 0; /* walk had no "haves" */

1135 +

1136 + pos = bitmap_position_packfile(bitmap_git, sha1);

1137 + if (pos < 0)

1138 + return 0;

1139 +

1140 + return bitmap_get(bitmap_git->haves, pos);

1141 +}

pack-bitmap.h

@@ -53,6 +53,13 @@ int rebuild_existing_bitmaps(struct bitmap_index *, struct packing_data *mapping

53 khash_sha1 *reused_bitmaps, int show_progress);

54 void free_bitmap_index(struct bitmap_index *);

56 +/*

57 + * After a traversal has been performed on the bitmap_index, this can be

58 + * queried to see if a particular object was reachable from any of the

59 + * objects flagged as UNINTERESTING.

60 + */

61 +int bitmap_has_sha1_in_uninteresting(struct bitmap_index *, const unsigned char *sha1);

62 +

63 void bitmap_writer_show_progress(int show);

64 void bitmap_writer_set_checksum(unsigned char *sha1);

65 void bitmap_writer_build_type_index(struct packing_data *to_pack,