diff options
author | Taylor Blau <me@ttaylorr.com> | 2023-12-15 01:24:28 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2023-12-15 01:38:08 +0300 |
commit | e1bfe30c4dd29a1a30569d04432d73675e497e86 (patch) | |
tree | c53dc9d441a7721ba71c61aecd07d2dd0170f4ed /pack-revindex.c | |
parent | b1e3333068247ddd44021a0b69457c249ddee7a1 (diff) |
pack-revindex: factor out `midx_key_to_pack_pos()` helper
The `midx_to_pack_pos()` function implements a binary search over
objects in the MIDX between lexical and pseudo-pack order. It does this
by taking in an index into the lexical order (i.e. the same argument
you'd use for `nth_midxed_object_id()` and similar) and spits out a
position in the pseudo-pack order.
This works for all callers, since they currently all are translating
from lexical order to pseudo-pack order. But future callers may want to
translate a known (offset, pack_id) tuple into an index into the
psuedo-pack order, without knowing where that (offset, pack_id) tuple
appears in lexical order.
Prepare for implementing a function that translates between a (offset,
pack_id) tuple into an index into the psuedo-pack order by extracting a
helper function which does just that, and then reimplementing
midx_to_pack_pos() in terms of it.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'pack-revindex.c')
-rw-r--r-- | pack-revindex.c | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/pack-revindex.c b/pack-revindex.c index 7dc6c776d5..baa4657ed3 100644 --- a/pack-revindex.c +++ b/pack-revindex.c @@ -520,19 +520,12 @@ static int midx_pack_order_cmp(const void *va, const void *vb) return 0; } -int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos) +static int midx_key_to_pack_pos(struct multi_pack_index *m, + struct midx_pack_key *key, + uint32_t *pos) { - struct midx_pack_key key; uint32_t *found; - if (!m->revindex_data) - BUG("midx_to_pack_pos: reverse index not yet loaded"); - if (m->num_objects <= at) - BUG("midx_to_pack_pos: out-of-bounds object at %"PRIu32, at); - - key.pack = nth_midxed_pack_int_id(m, at); - key.offset = nth_midxed_offset(m, at); - key.midx = m; /* * The preferred pack sorts first, so determine its identifier by * looking at the first object in pseudo-pack order. @@ -542,16 +535,32 @@ int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos) * implicitly is preferred (and includes all its objects, since ties are * broken first by pack identifier). */ - if (midx_preferred_pack(key.midx, &key.preferred_pack) < 0) + if (midx_preferred_pack(key->midx, &key->preferred_pack) < 0) return error(_("could not determine preferred pack")); - - found = bsearch(&key, m->revindex_data, m->num_objects, - sizeof(*m->revindex_data), midx_pack_order_cmp); + found = bsearch(key, m->revindex_data, m->num_objects, + sizeof(*m->revindex_data), + midx_pack_order_cmp); if (!found) - return error("bad offset for revindex"); + return -1; *pos = found - m->revindex_data; return 0; } + +int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos) +{ + struct midx_pack_key key; + + if (!m->revindex_data) + BUG("midx_to_pack_pos: reverse index not yet loaded"); + if (m->num_objects <= at) + BUG("midx_to_pack_pos: out-of-bounds object at %"PRIu32, at); + + key.pack = nth_midxed_pack_int_id(m, at); + key.offset = nth_midxed_offset(m, at); + key.midx = m; + + return midx_key_to_pack_pos(m, &key, pos); +} |