[PATCH v2 20/26] pack-revindex: implement `midx_pair_to_pack_pos()`
- From
Taylor Blau <me@ttaylorr.com>
- Date
- Dec 14, 2023, 22:24 UTC
- Message-ID
- <e99481014ed9dba161b30dea5e6af2b692f5ca9f.1702592604.git.me@ttaylorr.com>
- In-Reply-To
- <cover.1702592603.git.me@ttaylorr.com>
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> --- pack-revindex.c | 11 +++++++++++ pack-revindex.h | 3 +++ 2 files changed, 14 insertions(+)
diff --git a/pack-revindex.c b/pack-revindex.c index baa4657ed3..a7624d8be8 100644 --- a/pack-revindex.c +++ b/pack-revindex.c @@ -564,3 +564,14 @@ int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos) return midx_key_to_pack_pos(m, &key, pos); } + +int midx_pair_to_pack_pos(struct multi_pack_index *m, uint32_t pack_int_id, + off_t ofs, uint32_t *pos) +{ + struct midx_pack_key key = { + .pack = pack_int_id, + .offset = ofs, + .midx = m, + }; + return midx_key_to_pack_pos(m, &key, pos); +} diff --git a/pack-revindex.h b/pack-revindex.h index 6dd47efea1..422c2487ae 100644 --- a/pack-revindex.h +++ b/pack-revindex.h @@ -142,4 +142,7 @@ uint32_t pack_pos_to_midx(struct multi_pack_index *m, uint32_t pos); */ int midx_to_pack_pos(struct multi_pack_index *midx, uint32_t at, uint32_t *pos); +int midx_pair_to_pack_pos(struct multi_pack_index *midx, uint32_t pack_id, + off_t ofs, uint32_t *pos); + #endif
-- 2.43.0.102.ga31d690331.dirty