@matheusbsbs / matheus-bagliano / commits / dbd5c520d2

pack-revindex: implement `midx_pair_to_pack_pos()`

Now that we have extracted the `midx_key_to_pack_pos()` function, we can implement the `midx_pair_to_pack_pos()` function which accepts (pack_id, offset) tuples and returns an index into the psuedo-pack order. This will be used in a following commit in order to figure out whether or not the MIDX chose a given delta's base object from the same pack as the delta resides in. It will do so by locating the base object's offset in the pack, and then performing a binary search using the same pack ID with the base object's offset. If (and only if) it finds a match (at any position) we can guarantee that the MIDX selected both halves of the delta/base pair from the same pack. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Taylor Blau committed Dec 14, 2023 at 17:24 UTC dbd5c520d2bb168f58bde4ead407d35589142668

2 files changed +14

pack-revindex.c

+11

@@ -564,3 +564,14 @@ int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos)

564

565 return midx_key_to_pack_pos(m, &key, pos);

566 }

567 +

568 +int midx_pair_to_pack_pos(struct multi_pack_index *m, uint32_t pack_int_id,

569 + off_t ofs, uint32_t *pos)

570 +{

571 + struct midx_pack_key key = {

572 + .pack = pack_int_id,

573 + .offset = ofs,

574 + .midx = m,

575 + };

576 + return midx_key_to_pack_pos(m, &key, pos);

577 +}

pack-revindex.h

@@ -142,4 +142,7 @@ uint32_t pack_pos_to_midx(struct multi_pack_index *m, uint32_t pos);

142 */

143 int midx_to_pack_pos(struct multi_pack_index *midx, uint32_t at, uint32_t *pos);

144

145 +int midx_pair_to_pack_pos(struct multi_pack_index *midx, uint32_t pack_id,

146 + off_t ofs, uint32_t *pos);

147 +

148 #endif