pack-bitmap: read multi-pack bitmaps

This prepares the code in pack-bitmap to interpret the new multi-pack
bitmaps described in Documentation/technical/bitmap-format.txt, which
mostly involves converting bit positions to accommodate looking them up
in a MIDX.

Note that there are currently no writers who write multi-pack bitmaps,
and that this will be implemented in the subsequent commit. Note also
that get_midx_checksum() and get_midx_filename() are made non-static so
they can be called from pack-bitmap.c.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/midx.h b/midx.h
index 8684cf0fef..1172df1a71 100644
--- a/midx.h
+++ b/midx.h
@@ -42,6 +42,8 @@ struct multi_pack_index {
 #define MIDX_PROGRESS     (1 << 0)
 #define MIDX_WRITE_REV_INDEX (1 << 1)
 
+const unsigned char *get_midx_checksum(struct multi_pack_index *m);
+char *get_midx_filename(const char *object_dir);
 char *get_midx_rev_filename(struct multi_pack_index *m);
 
 struct multi_pack_index *load_multi_pack_index(const char *object_dir, int local);