From: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
The 'git multi-pack-index expire' command looks at the existing
mult-pack-index, counts the number of objects referenced in each
pack-file, deletes the pack-fils with no referenced objects, and
rewrites the multi-pack-index to no longer reference those packs.
Refactor the write_midx_file() method to call write_midx_internal()
which now takes an existing 'struct multi_pack_index' and a list
of pack-files to drop (as specified by the names of their pack-
indexes). As we write the new multi-pack-index, we drop those
file names from the list of known pack-files.
The expire_midx_packs() method removes the unreferenced pack-files
after carefully closing the packs to avoid open handles.
Test that a new pack-file that covers the contents of two other
pack-files leads to those pack-files being deleted during the
expire command. Be sure to read the multi-pack-index to ensure
it no longer references those packs.
Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
---
midx.c | 82 +++++++++++++++++++++++++++++++++++--
t/t5319-multi-pack-index.sh | 15 +++++++
2 files changed, 93 insertions(+), 4 deletions(-)
diff --git a/midx.c b/midx.c
index 3bd7183a53..043cd1fd97 100644
--- a/midx.c
+++ b/midx.c
@@ -751,7 +751,8 @@ static size_t write_midx_large_offsets(struct hashfile *f, uint32_t nr_large_off
return written;
}
-int write_midx_file(const char *object_dir)
+static int write_midx_internal(const char *object_dir, struct multi_pack_index *m,
+ struct string_list *packs_to_drop)
{
unsigned char cur_chunk, num_chunks = 0;
char *midx_name;
@@ -765,6 +766,7 @@ int write_midx_file(const char *object_dir)
uint32_t nr_entries, num_large_offsets = 0;
struct pack_midx_entry *entries = NULL;
int large_offsets_needed = 0;
+ int result = 0;
midx_name = get_midx_filename(object_dir);
if (safe_create_leading_directories(midx_name)) {
@@ -773,7 +775,10 @@ int write_midx_file(const char *object_dir)
midx_name);
}
- packs.m = load_multi_pack_index(object_dir, 1);
+ if (m)
+ packs.m = m;
+ else
+ packs.m = load_multi_pack_index(object_dir, 1);
packs.nr = 0;
packs.alloc_list = packs.m ? packs.m->num_packs : 16;
@@ -787,7 +792,25 @@ int write_midx_file(const char *object_dir)
ALLOC_ARRAY(packs.perm, packs.alloc_perm);
if (packs.m) {
+ int drop_index = 0, missing_drops = 0;
for (i = 0; i < packs.m->num_packs; i++) {
+ if (packs_to_drop && drop_index < packs_to_drop->nr) {
+ int cmp = strcmp(packs.m->pack_names[i],
+ packs_to_drop->items[drop_index].string);
+
+ if (!cmp) {
+ drop_index++;
+ continue;
+ } else if (cmp > 0) {
+ error(_("did not see pack-file %s to drop"),
+ packs_to_drop->items[drop_index].string);
+ drop_index++;
+ i--;
+ missing_drops++;
+ continue;
+ }
+ }
+
ALLOC_GROW(packs.list, packs.nr + 1, packs.alloc_list);
ALLOC_GROW(packs.names, packs.nr + 1, packs.alloc_names);
ALLOC_GROW(packs.perm, packs.nr + 1, packs.alloc_perm);
@@ -798,6 +821,12 @@ int write_midx_file(const char *object_dir)
packs.pack_name_concat_len += strlen(packs.names[packs.nr]) + 1;
packs.nr++;
}
+
+ if (packs_to_drop && (drop_index < packs_to_drop->nr || missing_drops)) {
+ error(_("did not see all pack-files to drop"));
+ result = 1;
+ goto cleanup;
+ }
}
for_each_file_in_pack_dir(object_dir, add_pack_to_midx, &packs);
@@ -932,7 +961,12 @@ int write_midx_file(const char *object_dir)
free(packs.perm);
free(entries);
free(midx_name);
- return 0;
+ return result;
+}
+
+int write_midx_file(const char *object_dir)
+{
+ return write_midx_internal(object_dir, NULL, NULL);
}
void clear_midx_file(struct repository *r)
@@ -1034,5 +1068,45 @@ int verify_midx_file(const char *object_dir)
int expire_midx_packs(const char *object_dir)
{
- return 0;
+ uint32_t i, *count, result = 0;
+ struct string_list packs_to_drop = STRING_LIST_INIT_DUP;
+ struct multi_pack_index *m = load_multi_pack_index(object_dir, 1);
+
+ if (!m)
+ return 0;
+
+ count = xcalloc(m->num_packs, sizeof(uint32_t));
+ for (i = 0; i < m->num_objects; i++) {
+ int pack_int_id = nth_midxed_pack_int_id(m, i);
+ count[pack_int_id]++;
+ }
+
+ for (i = 0; i < m->num_packs; i++) {
+ char *pack_name;
+
+ if (count[i])
+ continue;
+
+ if (prepare_midx_pack(m, i))
+ continue;
+
+ if (m->packs[i]->pack_keep)
+ continue;
+
+ pack_name = xstrdup(m->packs[i]->pack_name);
+ close_pack(m->packs[i]);
+ FREE_AND_NULL(m->packs[i]);
+
+ string_list_insert(&packs_to_drop, m->pack_names[i]);
+ unlink_pack_path(pack_name, 0);
+ free(pack_name);
+ }
+
+ free(count);
+
+ if (packs_to_drop.nr)
+ result = write_midx_internal(object_dir, m, &packs_to_drop);
+
+ string_list_clear(&packs_to_drop, 0);
+ return result;
}
diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh
index 948effc1ee..210279a3cf 100755
--- a/t/t5319-multi-pack-index.sh
+++ b/t/t5319-multi-pack-index.sh
@@ -395,4 +395,19 @@ test_expect_success 'expire does not remove any packs' '
)
'
+test_expect_success 'expire removes unreferenced packs' '
+ (
+ cd dup &&
+ git pack-objects --revs .git/objects/pack/pack-combined <<-EOF &&
+ refs/heads/A
+ ^refs/heads/C
+ EOF
+ git multi-pack-index write &&
+ ls .git/objects/pack | grep -v -e pack-[AB] >expect &&
+ git multi-pack-index expire &&
+ ls .git/objects/pack >actual &&
+ test_cmp expect actual
+ )
+'
+
test_done
--
gitgitgadget
