midx: use `strset` for retained MIDX files
Both `clear_midx_files_ext()` and `clear_incremental_midx_files_ext()` build a list of filenames to keep while pruning stale MIDX files. Today they hand-roll an array instead of using a `strset`, thus requiring us to pass an additional length parameter, and makes lookups linear. Replace the bare array with a `strset` which can be passed around as a single parameter. Though it improves lookup performance, the difference is likely immeasurable given how small the keep_hashes array typically is. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau committed
May 19, 2026 at 11:57 UTC
ddaa7a6fb79038a30b59341ed3f0f2097014ccbf
1 file changed
+27
-30
midx.c
+27
-30
index 81d6ab11e6..f75e3c9fa6 100644
--- a/midx.c
+++ b/midx.c
@@ -758,8 +758,7 @@ int midx_checksum_valid(struct multi_pack_index *m)
}
struct clear_midx_data {
- char **keep;
- uint32_t keep_nr;
+ struct strset keep;
const char *ext;
};
@@ -767,15 +766,12 @@ static void clear_midx_file_ext(const char *full_path, size_t full_path_len UNUS
const char *file_name, void *_data)
{
struct clear_midx_data *data = _data;
- uint32_t i;
if (!(starts_with(file_name, "multi-pack-index-") &&
ends_with(file_name, data->ext)))
return;
- for (i = 0; i < data->keep_nr; i++) {
- if (!strcmp(data->keep[i], file_name))
- return;
- }
+ if (strset_contains(&data->keep, file_name))
+ return;
if (unlink(full_path))
die_errno(_("failed to remove %s"), full_path);
}
@@ -783,48 +779,49 @@ static void clear_midx_file_ext(const char *full_path, size_t full_path_len UNUS
void clear_midx_files_ext(struct odb_source *source, const char *ext,
const char *keep_hash)
{
- struct clear_midx_data data;
- memset(&data, 0, sizeof(struct clear_midx_data));
+ struct clear_midx_data data = {
+ .keep = STRSET_INIT,
+ .ext = ext,
+ };
if (keep_hash) {
- ALLOC_ARRAY(data.keep, 1);
+ struct strbuf buf = STRBUF_INIT;
+ strbuf_addf(&buf, "multi-pack-index-%s.%s", keep_hash, ext);
+
+ strset_add(&data.keep, buf.buf);
- data.keep[0] = xstrfmt("multi-pack-index-%s.%s", keep_hash, ext);
- data.keep_nr = 1;
+ strbuf_release(&buf);
}
- data.ext = ext;
- for_each_file_in_pack_dir(source->path,
- clear_midx_file_ext,
- &data);
+ for_each_file_in_pack_dir(source->path, clear_midx_file_ext, &data);
- if (keep_hash)
- free(data.keep[0]);
- free(data.keep);
+ strset_clear(&data.keep);
}
void clear_incremental_midx_files_ext(struct odb_source *source, const char *ext,
char **keep_hashes,
uint32_t hashes_nr)
{
- struct clear_midx_data data;
+ struct clear_midx_data data = {
+ .keep = STRSET_INIT,
+ .ext = ext,
+ };
+ struct strbuf buf = STRBUF_INIT;
uint32_t i;
- memset(&data, 0, sizeof(struct clear_midx_data));
+ for (i = 0; i < hashes_nr; i++) {
+ strbuf_reset(&buf);
+ strbuf_addf(&buf, "multi-pack-index-%s.%s", keep_hashes[i],
+ ext);
- ALLOC_ARRAY(data.keep, hashes_nr);
- for (i = 0; i < hashes_nr; i++)
- data.keep[i] = xstrfmt("multi-pack-index-%s.%s", keep_hashes[i],
- ext);
- data.keep_nr = hashes_nr;
- data.ext = ext;
+ strset_add(&data.keep, buf.buf);
+ }
for_each_file_in_pack_subdir(source->path, "multi-pack-index.d",
clear_midx_file_ext, &data);
- for (i = 0; i < hashes_nr; i++)
- free(data.keep[i]);
- free(data.keep);
+ strbuf_release(&buf);
+ strset_clear(&data.keep);
}
void clear_midx_file(struct repository *r)