diff options
| -rw-r--r-- | Documentation/technical/pack-format.txt | 5 | ||||
| -rw-r--r-- | midx.c | 53 | ||||
| -rw-r--r-- | midx.h | 1 | ||||
| -rw-r--r-- | t/helper/test-read-midx.c | 4 | ||||
| -rwxr-xr-x | t/t5319-multi-pack-index.sh | 16 |
5 files changed, 68 insertions, 11 deletions
diff --git a/Documentation/technical/pack-format.txt b/Documentation/technical/pack-format.txt index 78ee0489c6..3215f7bfcd 100644 --- a/Documentation/technical/pack-format.txt +++ b/Documentation/technical/pack-format.txt @@ -302,6 +302,11 @@ CHUNK DATA: name. This is the only chunk not guaranteed to be a multiple of four bytes in length, so should be the last chunk for alignment reasons. + OID Fanout (ID: {'O', 'I', 'D', 'F'}) + The ith entry, F[i], stores the number of OIDs with first + byte at most i. Thus F[255] stores the total + number of objects. + OID Lookup (ID: {'O', 'I', 'D', 'L'}) The OIDs for all objects in the MIDX are stored in lexicographic order in this chunk. @@ -18,11 +18,13 @@ #define MIDX_HASH_LEN 20 #define MIDX_MIN_SIZE (MIDX_HEADER_SIZE + MIDX_HASH_LEN) -#define MIDX_MAX_CHUNKS 2 +#define MIDX_MAX_CHUNKS 3 #define MIDX_CHUNK_ALIGNMENT 4 #define MIDX_CHUNKID_PACKNAMES 0x504e414d /* "PNAM" */ +#define MIDX_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */ #define MIDX_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */ #define MIDX_CHUNKLOOKUP_WIDTH (sizeof(uint32_t) + sizeof(uint64_t)) +#define MIDX_CHUNK_FANOUT_SIZE (sizeof(uint32_t) * 256) static char *get_midx_filename(const char *object_dir) { @@ -102,6 +104,10 @@ struct multi_pack_index *load_multi_pack_index(const char *object_dir) m->chunk_pack_names = m->data + chunk_offset; break; + case MIDX_CHUNKID_OIDFANOUT: + m->chunk_oid_fanout = (uint32_t *)(m->data + chunk_offset); + break; + case MIDX_CHUNKID_OIDLOOKUP: m->chunk_oid_lookup = m->data + chunk_offset; break; @@ -121,9 +127,13 @@ struct multi_pack_index *load_multi_pack_index(const char *object_dir) if (!m->chunk_pack_names) die(_("multi-pack-index missing required pack-name chunk")); + if (!m->chunk_oid_fanout) + die(_("multi-pack-index missing required OID fanout chunk")); if (!m->chunk_oid_lookup) die(_("multi-pack-index missing required OID lookup chunk")); + m->num_objects = ntohl(m->chunk_oid_fanout[255]); + m->pack_names = xcalloc(m->num_packs, sizeof(*m->pack_names)); cur_pack_name = (const char *)m->chunk_pack_names; @@ -389,6 +399,35 @@ static size_t write_midx_pack_names(struct hashfile *f, return written; } +static size_t write_midx_oid_fanout(struct hashfile *f, + struct pack_midx_entry *objects, + uint32_t nr_objects) +{ + struct pack_midx_entry *list = objects; + struct pack_midx_entry *last = objects + nr_objects; + uint32_t count = 0; + uint32_t i; + + /* + * Write the first-level table (the list is sorted, + * but we use a 256-entry lookup to be able to avoid + * having to do eight extra binary search iterations). + */ + for (i = 0; i < 256; i++) { + struct pack_midx_entry *next = list; + + while (next < last && next->oid.hash[0] == i) { + count++; + next++; + } + + hashwrite_be32(f, count); + list = next; + } + + return MIDX_CHUNK_FANOUT_SIZE; +} + static size_t write_midx_oid_lookup(struct hashfile *f, unsigned char hash_len, struct pack_midx_entry *objects, uint32_t nr_objects) @@ -461,7 +500,7 @@ int write_midx_file(const char *object_dir) FREE_AND_NULL(midx_name); cur_chunk = 0; - num_chunks = 2; + num_chunks = 3; written = write_midx_header(f, num_chunks, packs.nr); @@ -469,10 +508,14 @@ int write_midx_file(const char *object_dir) chunk_offsets[cur_chunk] = written + (num_chunks + 1) * MIDX_CHUNKLOOKUP_WIDTH; cur_chunk++; - chunk_ids[cur_chunk] = MIDX_CHUNKID_OIDLOOKUP; + chunk_ids[cur_chunk] = MIDX_CHUNKID_OIDFANOUT; chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + packs.pack_name_concat_len; cur_chunk++; + chunk_ids[cur_chunk] = MIDX_CHUNKID_OIDLOOKUP; + chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + MIDX_CHUNK_FANOUT_SIZE; + + cur_chunk++; chunk_ids[cur_chunk] = 0; chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + nr_entries * MIDX_HASH_LEN; @@ -505,6 +548,10 @@ int write_midx_file(const char *object_dir) written += write_midx_pack_names(f, packs.names, packs.nr); break; + case MIDX_CHUNKID_OIDFANOUT: + written += write_midx_oid_fanout(f, entries, nr_entries); + break; + case MIDX_CHUNKID_OIDLOOKUP: written += write_midx_oid_lookup(f, MIDX_HASH_LEN, entries, nr_entries); break; @@ -15,6 +15,7 @@ struct multi_pack_index { uint32_t num_objects; const unsigned char *chunk_pack_names; + const uint32_t *chunk_oid_fanout; const unsigned char *chunk_oid_lookup; const char **pack_names; diff --git a/t/helper/test-read-midx.c b/t/helper/test-read-midx.c index de6d452a7c..f7c17b0940 100644 --- a/t/helper/test-read-midx.c +++ b/t/helper/test-read-midx.c @@ -22,10 +22,12 @@ static int read_midx_file(const char *object_dir) if (m->chunk_pack_names) printf(" pack-names"); + if (m->chunk_oid_fanout) + printf(" oid-fanout"); if (m->chunk_oid_lookup) printf(" oid-lookup"); - printf("\n"); + printf("\nnum_objects: %d\n", m->num_objects); printf("packs:\n"); for (i = 0; i < m->num_packs; i++) diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh index 4813610115..95e731ae52 100755 --- a/t/t5319-multi-pack-index.sh +++ b/t/t5319-multi-pack-index.sh @@ -5,10 +5,12 @@ test_description='multi-pack-indexes' midx_read_expect () { NUM_PACKS=$1 + NUM_OBJECTS=$2 { cat <<-EOF && - header: 4d494458 1 2 $NUM_PACKS - chunks: pack-names oid-lookup + header: 4d494458 1 3 $NUM_PACKS + chunks: pack-names oid-fanout oid-lookup + num_objects: $NUM_OBJECTS packs: EOF if test $NUM_PACKS -ge 1 @@ -24,7 +26,7 @@ midx_read_expect () { test_expect_success 'write midx with no packs' ' test_when_finished rm -f pack/multi-pack-index && git multi-pack-index --object-dir=. write && - midx_read_expect 0 + midx_read_expect 0 0 ' generate_objects () { @@ -74,13 +76,13 @@ test_expect_success 'write midx with one v1 pack' ' pack=$(git pack-objects --index-version=1 pack/test <obj-list) && test_when_finished rm pack/test-$pack.pack pack/test-$pack.idx pack/multi-pack-index && git multi-pack-index --object-dir=. write && - midx_read_expect 1 + midx_read_expect 1 18 ' test_expect_success 'write midx with one v2 pack' ' git pack-objects --index-version=2,0x40 pack/test <obj-list && git multi-pack-index --object-dir=. write && - midx_read_expect 1 + midx_read_expect 1 18 ' test_expect_success 'add more objects' ' @@ -94,7 +96,7 @@ test_expect_success 'add more objects' ' test_expect_success 'write midx with two packs' ' git pack-objects --index-version=1 pack/test-2 <obj-list && git multi-pack-index --object-dir=. write && - midx_read_expect 2 + midx_read_expect 2 34 ' test_expect_success 'add more packs' ' @@ -108,7 +110,7 @@ test_expect_success 'add more packs' ' test_expect_success 'write midx with twelve packs' ' git multi-pack-index --object-dir=. write && - midx_read_expect 12 + midx_read_expect 12 74 ' test_done |