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af96fe3392
The multi-pack-index allows searching for objects across multiple packs using one object list. The original design gains many of these performance benefits by keeping the packs in the multi-pack-index out of the packed_git list. Unfortunately, this has one major drawback. If the multi-pack-index covers thousands of packs, and a command loads many of those packs, then we can hit the limit for open file descriptors. The close_one_pack() method is used to limit this resource, but it only looks at the packed_git list, and uses an LRU cache to prevent thrashing. Instead of complicating this close_one_pack() logic to include direct references to the multi-pack-index, simply add the packs opened by the multi-pack-index to the packed_git list. This immediately solves the file-descriptor limit problem, but requires some extra steps to avoid performance issues or other problems: 1. Create a multi_pack_index bit in the packed_git struct that is one if and only if the pack was loaded from a multi-pack-index. 2. Skip packs with the multi_pack_index bit when doing object lookups and abbreviations. These algorithms already check the multi-pack-index before the packed_git struct. This has a very small performance hit, as we need to walk more packed_git structs. This is acceptable, since these operations run binary search on the other packs, so this walk-and-ignore logic is very fast by comparison. 3. When closing a multi-pack-index file, do not close its packs, as those packs will be closed using close_all_packs(). In some cases, such as 'git repack', we run 'close_midx()' without also closing the packs, so we need to un-set the multi_pack_index bit in those packs. This is necessary, and caught by running t6501-freshen-objects.sh with GIT_TEST_MULTI_PACK_INDEX=1. To manually test this change, I inserted trace2 logging into close_pack_fd() and set pack_max_fds to 10, then ran 'git rev-list --all --objects' on a copy of the Git repo with 300+ pack-files and a multi-pack-index. The logs verified the packs are closed as we read them beyond the file descriptor limit. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
1142 lines
30 KiB
C
1142 lines
30 KiB
C
#include "cache.h"
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#include "config.h"
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#include "csum-file.h"
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#include "dir.h"
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#include "lockfile.h"
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#include "packfile.h"
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#include "object-store.h"
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#include "sha1-lookup.h"
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#include "midx.h"
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#include "progress.h"
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#include "trace2.h"
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#define MIDX_SIGNATURE 0x4d494458 /* "MIDX" */
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#define MIDX_VERSION 1
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#define MIDX_BYTE_FILE_VERSION 4
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#define MIDX_BYTE_HASH_VERSION 5
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#define MIDX_BYTE_NUM_CHUNKS 6
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#define MIDX_BYTE_NUM_PACKS 8
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#define MIDX_HASH_VERSION 1
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#define MIDX_HEADER_SIZE 12
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#define MIDX_HASH_LEN 20
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#define MIDX_MIN_SIZE (MIDX_HEADER_SIZE + MIDX_HASH_LEN)
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#define MIDX_MAX_CHUNKS 5
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#define MIDX_CHUNK_ALIGNMENT 4
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#define MIDX_CHUNKID_PACKNAMES 0x504e414d /* "PNAM" */
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#define MIDX_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
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#define MIDX_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
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#define MIDX_CHUNKID_OBJECTOFFSETS 0x4f4f4646 /* "OOFF" */
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#define MIDX_CHUNKID_LARGEOFFSETS 0x4c4f4646 /* "LOFF" */
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#define MIDX_CHUNKLOOKUP_WIDTH (sizeof(uint32_t) + sizeof(uint64_t))
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#define MIDX_CHUNK_FANOUT_SIZE (sizeof(uint32_t) * 256)
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#define MIDX_CHUNK_OFFSET_WIDTH (2 * sizeof(uint32_t))
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#define MIDX_CHUNK_LARGE_OFFSET_WIDTH (sizeof(uint64_t))
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#define MIDX_LARGE_OFFSET_NEEDED 0x80000000
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static char *get_midx_filename(const char *object_dir)
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{
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return xstrfmt("%s/pack/multi-pack-index", object_dir);
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}
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struct multi_pack_index *load_multi_pack_index(const char *object_dir, int local)
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{
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struct multi_pack_index *m = NULL;
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int fd;
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struct stat st;
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size_t midx_size;
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void *midx_map = NULL;
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uint32_t hash_version;
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char *midx_name = get_midx_filename(object_dir);
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uint32_t i;
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const char *cur_pack_name;
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fd = git_open(midx_name);
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if (fd < 0)
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goto cleanup_fail;
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if (fstat(fd, &st)) {
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error_errno(_("failed to read %s"), midx_name);
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goto cleanup_fail;
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}
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midx_size = xsize_t(st.st_size);
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if (midx_size < MIDX_MIN_SIZE) {
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error(_("multi-pack-index file %s is too small"), midx_name);
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goto cleanup_fail;
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}
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FREE_AND_NULL(midx_name);
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midx_map = xmmap(NULL, midx_size, PROT_READ, MAP_PRIVATE, fd, 0);
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FLEX_ALLOC_STR(m, object_dir, object_dir);
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m->fd = fd;
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m->data = midx_map;
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m->data_len = midx_size;
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m->local = local;
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m->signature = get_be32(m->data);
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if (m->signature != MIDX_SIGNATURE)
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die(_("multi-pack-index signature 0x%08x does not match signature 0x%08x"),
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m->signature, MIDX_SIGNATURE);
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m->version = m->data[MIDX_BYTE_FILE_VERSION];
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if (m->version != MIDX_VERSION)
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die(_("multi-pack-index version %d not recognized"),
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m->version);
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hash_version = m->data[MIDX_BYTE_HASH_VERSION];
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if (hash_version != MIDX_HASH_VERSION)
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die(_("hash version %u does not match"), hash_version);
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m->hash_len = MIDX_HASH_LEN;
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m->num_chunks = m->data[MIDX_BYTE_NUM_CHUNKS];
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m->num_packs = get_be32(m->data + MIDX_BYTE_NUM_PACKS);
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for (i = 0; i < m->num_chunks; i++) {
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uint32_t chunk_id = get_be32(m->data + MIDX_HEADER_SIZE +
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MIDX_CHUNKLOOKUP_WIDTH * i);
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uint64_t chunk_offset = get_be64(m->data + MIDX_HEADER_SIZE + 4 +
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MIDX_CHUNKLOOKUP_WIDTH * i);
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if (chunk_offset >= m->data_len)
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die(_("invalid chunk offset (too large)"));
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switch (chunk_id) {
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case MIDX_CHUNKID_PACKNAMES:
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m->chunk_pack_names = m->data + chunk_offset;
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break;
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case MIDX_CHUNKID_OIDFANOUT:
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m->chunk_oid_fanout = (uint32_t *)(m->data + chunk_offset);
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break;
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case MIDX_CHUNKID_OIDLOOKUP:
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m->chunk_oid_lookup = m->data + chunk_offset;
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break;
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case MIDX_CHUNKID_OBJECTOFFSETS:
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m->chunk_object_offsets = m->data + chunk_offset;
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break;
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case MIDX_CHUNKID_LARGEOFFSETS:
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m->chunk_large_offsets = m->data + chunk_offset;
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break;
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case 0:
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die(_("terminating multi-pack-index chunk id appears earlier than expected"));
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break;
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default:
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/*
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* Do nothing on unrecognized chunks, allowing future
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* extensions to add optional chunks.
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*/
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break;
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}
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}
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if (!m->chunk_pack_names)
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die(_("multi-pack-index missing required pack-name chunk"));
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if (!m->chunk_oid_fanout)
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die(_("multi-pack-index missing required OID fanout chunk"));
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if (!m->chunk_oid_lookup)
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die(_("multi-pack-index missing required OID lookup chunk"));
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if (!m->chunk_object_offsets)
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die(_("multi-pack-index missing required object offsets chunk"));
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m->num_objects = ntohl(m->chunk_oid_fanout[255]);
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m->pack_names = xcalloc(m->num_packs, sizeof(*m->pack_names));
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m->packs = xcalloc(m->num_packs, sizeof(*m->packs));
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cur_pack_name = (const char *)m->chunk_pack_names;
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for (i = 0; i < m->num_packs; i++) {
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m->pack_names[i] = cur_pack_name;
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cur_pack_name += strlen(cur_pack_name) + 1;
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if (i && strcmp(m->pack_names[i], m->pack_names[i - 1]) <= 0)
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die(_("multi-pack-index pack names out of order: '%s' before '%s'"),
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m->pack_names[i - 1],
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m->pack_names[i]);
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}
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trace2_data_intmax("midx", the_repository, "load/num_packs", m->num_packs);
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trace2_data_intmax("midx", the_repository, "load/num_objects", m->num_objects);
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return m;
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cleanup_fail:
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free(m);
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free(midx_name);
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if (midx_map)
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munmap(midx_map, midx_size);
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if (0 <= fd)
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close(fd);
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return NULL;
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}
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void close_midx(struct multi_pack_index *m)
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{
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uint32_t i;
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if (!m)
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return;
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munmap((unsigned char *)m->data, m->data_len);
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close(m->fd);
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m->fd = -1;
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for (i = 0; i < m->num_packs; i++) {
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if (m->packs[i])
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m->packs[i]->multi_pack_index = 0;
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}
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FREE_AND_NULL(m->packs);
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FREE_AND_NULL(m->pack_names);
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}
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int prepare_midx_pack(struct repository *r, struct multi_pack_index *m, uint32_t pack_int_id)
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{
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struct strbuf pack_name = STRBUF_INIT;
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struct packed_git *p;
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if (pack_int_id >= m->num_packs)
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die(_("bad pack-int-id: %u (%u total packs)"),
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pack_int_id, m->num_packs);
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if (m->packs[pack_int_id])
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return 0;
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strbuf_addf(&pack_name, "%s/pack/%s", m->object_dir,
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m->pack_names[pack_int_id]);
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p = add_packed_git(pack_name.buf, pack_name.len, m->local);
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strbuf_release(&pack_name);
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if (!p)
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return 1;
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p->multi_pack_index = 1;
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m->packs[pack_int_id] = p;
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install_packed_git(r, p);
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list_add_tail(&p->mru, &r->objects->packed_git_mru);
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return 0;
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}
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int bsearch_midx(const struct object_id *oid, struct multi_pack_index *m, uint32_t *result)
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{
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return bsearch_hash(oid->hash, m->chunk_oid_fanout, m->chunk_oid_lookup,
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MIDX_HASH_LEN, result);
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}
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struct object_id *nth_midxed_object_oid(struct object_id *oid,
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struct multi_pack_index *m,
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uint32_t n)
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{
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if (n >= m->num_objects)
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return NULL;
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hashcpy(oid->hash, m->chunk_oid_lookup + m->hash_len * n);
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return oid;
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}
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static off_t nth_midxed_offset(struct multi_pack_index *m, uint32_t pos)
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{
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const unsigned char *offset_data;
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uint32_t offset32;
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offset_data = m->chunk_object_offsets + pos * MIDX_CHUNK_OFFSET_WIDTH;
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offset32 = get_be32(offset_data + sizeof(uint32_t));
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if (m->chunk_large_offsets && offset32 & MIDX_LARGE_OFFSET_NEEDED) {
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if (sizeof(off_t) < sizeof(uint64_t))
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die(_("multi-pack-index stores a 64-bit offset, but off_t is too small"));
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offset32 ^= MIDX_LARGE_OFFSET_NEEDED;
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return get_be64(m->chunk_large_offsets + sizeof(uint64_t) * offset32);
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}
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return offset32;
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}
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static uint32_t nth_midxed_pack_int_id(struct multi_pack_index *m, uint32_t pos)
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{
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return get_be32(m->chunk_object_offsets + pos * MIDX_CHUNK_OFFSET_WIDTH);
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}
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static int nth_midxed_pack_entry(struct repository *r,
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struct multi_pack_index *m,
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struct pack_entry *e,
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uint32_t pos)
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{
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uint32_t pack_int_id;
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struct packed_git *p;
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if (pos >= m->num_objects)
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return 0;
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pack_int_id = nth_midxed_pack_int_id(m, pos);
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if (prepare_midx_pack(r, m, pack_int_id))
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die(_("error preparing packfile from multi-pack-index"));
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p = m->packs[pack_int_id];
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/*
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* We are about to tell the caller where they can locate the
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* requested object. We better make sure the packfile is
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* still here and can be accessed before supplying that
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* answer, as it may have been deleted since the MIDX was
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* loaded!
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*/
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if (!is_pack_valid(p))
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return 0;
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if (p->num_bad_objects) {
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uint32_t i;
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struct object_id oid;
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nth_midxed_object_oid(&oid, m, pos);
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for (i = 0; i < p->num_bad_objects; i++)
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if (hasheq(oid.hash,
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p->bad_object_sha1 + the_hash_algo->rawsz * i))
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return 0;
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}
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e->offset = nth_midxed_offset(m, pos);
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e->p = p;
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return 1;
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}
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int fill_midx_entry(struct repository * r,
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const struct object_id *oid,
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struct pack_entry *e,
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struct multi_pack_index *m)
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{
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uint32_t pos;
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if (!bsearch_midx(oid, m, &pos))
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return 0;
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return nth_midxed_pack_entry(r, m, e, pos);
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}
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/* Match "foo.idx" against either "foo.pack" _or_ "foo.idx". */
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static int cmp_idx_or_pack_name(const char *idx_or_pack_name,
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const char *idx_name)
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{
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/* Skip past any initial matching prefix. */
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while (*idx_name && *idx_name == *idx_or_pack_name) {
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idx_name++;
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idx_or_pack_name++;
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}
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/*
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* If we didn't match completely, we may have matched "pack-1234." and
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* be left with "idx" and "pack" respectively, which is also OK. We do
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* not have to check for "idx" and "idx", because that would have been
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* a complete match (and in that case these strcmps will be false, but
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* we'll correctly return 0 from the final strcmp() below.
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*
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* Technically this matches "fooidx" and "foopack", but we'd never have
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* such names in the first place.
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*/
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if (!strcmp(idx_name, "idx") && !strcmp(idx_or_pack_name, "pack"))
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return 0;
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/*
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* This not only checks for a complete match, but also orders based on
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* the first non-identical character, which means our ordering will
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* match a raw strcmp(). That makes it OK to use this to binary search
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* a naively-sorted list.
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*/
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return strcmp(idx_or_pack_name, idx_name);
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}
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int midx_contains_pack(struct multi_pack_index *m, const char *idx_or_pack_name)
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{
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uint32_t first = 0, last = m->num_packs;
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while (first < last) {
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uint32_t mid = first + (last - first) / 2;
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const char *current;
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int cmp;
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current = m->pack_names[mid];
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cmp = cmp_idx_or_pack_name(idx_or_pack_name, current);
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if (!cmp)
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return 1;
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if (cmp > 0) {
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first = mid + 1;
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continue;
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}
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last = mid;
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}
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return 0;
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}
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int prepare_multi_pack_index_one(struct repository *r, const char *object_dir, int local)
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{
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struct multi_pack_index *m;
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struct multi_pack_index *m_search;
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int config_value;
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static int env_value = -1;
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if (env_value < 0)
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env_value = git_env_bool(GIT_TEST_MULTI_PACK_INDEX, 0);
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if (!env_value &&
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(repo_config_get_bool(r, "core.multipackindex", &config_value) ||
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!config_value))
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return 0;
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for (m_search = r->objects->multi_pack_index; m_search; m_search = m_search->next)
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if (!strcmp(object_dir, m_search->object_dir))
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return 1;
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m = load_multi_pack_index(object_dir, local);
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if (m) {
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m->next = r->objects->multi_pack_index;
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r->objects->multi_pack_index = m;
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return 1;
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}
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return 0;
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}
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static size_t write_midx_header(struct hashfile *f,
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unsigned char num_chunks,
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uint32_t num_packs)
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{
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unsigned char byte_values[4];
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hashwrite_be32(f, MIDX_SIGNATURE);
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byte_values[0] = MIDX_VERSION;
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byte_values[1] = MIDX_HASH_VERSION;
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byte_values[2] = num_chunks;
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byte_values[3] = 0; /* unused */
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hashwrite(f, byte_values, sizeof(byte_values));
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hashwrite_be32(f, num_packs);
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return MIDX_HEADER_SIZE;
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}
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struct pack_list {
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struct packed_git **list;
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char **names;
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uint32_t nr;
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uint32_t alloc_list;
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uint32_t alloc_names;
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size_t pack_name_concat_len;
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struct multi_pack_index *m;
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};
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static void add_pack_to_midx(const char *full_path, size_t full_path_len,
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const char *file_name, void *data)
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{
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struct pack_list *packs = (struct pack_list *)data;
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if (ends_with(file_name, ".idx")) {
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if (packs->m && midx_contains_pack(packs->m, file_name))
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return;
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ALLOC_GROW(packs->list, packs->nr + 1, packs->alloc_list);
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ALLOC_GROW(packs->names, packs->nr + 1, packs->alloc_names);
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packs->list[packs->nr] = add_packed_git(full_path,
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full_path_len,
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0);
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if (!packs->list[packs->nr]) {
|
|
warning(_("failed to add packfile '%s'"),
|
|
full_path);
|
|
return;
|
|
}
|
|
|
|
if (open_pack_index(packs->list[packs->nr])) {
|
|
warning(_("failed to open pack-index '%s'"),
|
|
full_path);
|
|
close_pack(packs->list[packs->nr]);
|
|
FREE_AND_NULL(packs->list[packs->nr]);
|
|
return;
|
|
}
|
|
|
|
packs->names[packs->nr] = xstrdup(file_name);
|
|
packs->pack_name_concat_len += strlen(file_name) + 1;
|
|
packs->nr++;
|
|
}
|
|
}
|
|
|
|
struct pack_pair {
|
|
uint32_t pack_int_id;
|
|
char *pack_name;
|
|
};
|
|
|
|
static int pack_pair_compare(const void *_a, const void *_b)
|
|
{
|
|
struct pack_pair *a = (struct pack_pair *)_a;
|
|
struct pack_pair *b = (struct pack_pair *)_b;
|
|
return strcmp(a->pack_name, b->pack_name);
|
|
}
|
|
|
|
static void sort_packs_by_name(char **pack_names, uint32_t nr_packs, uint32_t *perm)
|
|
{
|
|
uint32_t i;
|
|
struct pack_pair *pairs;
|
|
|
|
ALLOC_ARRAY(pairs, nr_packs);
|
|
|
|
for (i = 0; i < nr_packs; i++) {
|
|
pairs[i].pack_int_id = i;
|
|
pairs[i].pack_name = pack_names[i];
|
|
}
|
|
|
|
QSORT(pairs, nr_packs, pack_pair_compare);
|
|
|
|
for (i = 0; i < nr_packs; i++) {
|
|
pack_names[i] = pairs[i].pack_name;
|
|
perm[pairs[i].pack_int_id] = i;
|
|
}
|
|
|
|
free(pairs);
|
|
}
|
|
|
|
struct pack_midx_entry {
|
|
struct object_id oid;
|
|
uint32_t pack_int_id;
|
|
time_t pack_mtime;
|
|
uint64_t offset;
|
|
};
|
|
|
|
static int midx_oid_compare(const void *_a, const void *_b)
|
|
{
|
|
const struct pack_midx_entry *a = (const struct pack_midx_entry *)_a;
|
|
const struct pack_midx_entry *b = (const struct pack_midx_entry *)_b;
|
|
int cmp = oidcmp(&a->oid, &b->oid);
|
|
|
|
if (cmp)
|
|
return cmp;
|
|
|
|
if (a->pack_mtime > b->pack_mtime)
|
|
return -1;
|
|
else if (a->pack_mtime < b->pack_mtime)
|
|
return 1;
|
|
|
|
return a->pack_int_id - b->pack_int_id;
|
|
}
|
|
|
|
static int nth_midxed_pack_midx_entry(struct multi_pack_index *m,
|
|
uint32_t *pack_perm,
|
|
struct pack_midx_entry *e,
|
|
uint32_t pos)
|
|
{
|
|
if (pos >= m->num_objects)
|
|
return 1;
|
|
|
|
nth_midxed_object_oid(&e->oid, m, pos);
|
|
e->pack_int_id = pack_perm[nth_midxed_pack_int_id(m, pos)];
|
|
e->offset = nth_midxed_offset(m, pos);
|
|
|
|
/* consider objects in midx to be from "old" packs */
|
|
e->pack_mtime = 0;
|
|
return 0;
|
|
}
|
|
|
|
static void fill_pack_entry(uint32_t pack_int_id,
|
|
struct packed_git *p,
|
|
uint32_t cur_object,
|
|
struct pack_midx_entry *entry)
|
|
{
|
|
if (!nth_packed_object_oid(&entry->oid, p, cur_object))
|
|
die(_("failed to locate object %d in packfile"), cur_object);
|
|
|
|
entry->pack_int_id = pack_int_id;
|
|
entry->pack_mtime = p->mtime;
|
|
|
|
entry->offset = nth_packed_object_offset(p, cur_object);
|
|
}
|
|
|
|
/*
|
|
* It is possible to artificially get into a state where there are many
|
|
* duplicate copies of objects. That can create high memory pressure if
|
|
* we are to create a list of all objects before de-duplication. To reduce
|
|
* this memory pressure without a significant performance drop, automatically
|
|
* group objects by the first byte of their object id. Use the IDX fanout
|
|
* tables to group the data, copy to a local array, then sort.
|
|
*
|
|
* Copy only the de-duplicated entries (selected by most-recent modified time
|
|
* of a packfile containing the object).
|
|
*/
|
|
static struct pack_midx_entry *get_sorted_entries(struct multi_pack_index *m,
|
|
struct packed_git **p,
|
|
uint32_t *perm,
|
|
uint32_t nr_packs,
|
|
uint32_t *nr_objects)
|
|
{
|
|
uint32_t cur_fanout, cur_pack, cur_object;
|
|
uint32_t alloc_fanout, alloc_objects, total_objects = 0;
|
|
struct pack_midx_entry *entries_by_fanout = NULL;
|
|
struct pack_midx_entry *deduplicated_entries = NULL;
|
|
uint32_t start_pack = m ? m->num_packs : 0;
|
|
|
|
for (cur_pack = start_pack; cur_pack < nr_packs; cur_pack++)
|
|
total_objects += p[cur_pack]->num_objects;
|
|
|
|
/*
|
|
* As we de-duplicate by fanout value, we expect the fanout
|
|
* slices to be evenly distributed, with some noise. Hence,
|
|
* allocate slightly more than one 256th.
|
|
*/
|
|
alloc_objects = alloc_fanout = total_objects > 3200 ? total_objects / 200 : 16;
|
|
|
|
ALLOC_ARRAY(entries_by_fanout, alloc_fanout);
|
|
ALLOC_ARRAY(deduplicated_entries, alloc_objects);
|
|
*nr_objects = 0;
|
|
|
|
for (cur_fanout = 0; cur_fanout < 256; cur_fanout++) {
|
|
uint32_t nr_fanout = 0;
|
|
|
|
if (m) {
|
|
uint32_t start = 0, end;
|
|
|
|
if (cur_fanout)
|
|
start = ntohl(m->chunk_oid_fanout[cur_fanout - 1]);
|
|
end = ntohl(m->chunk_oid_fanout[cur_fanout]);
|
|
|
|
for (cur_object = start; cur_object < end; cur_object++) {
|
|
ALLOC_GROW(entries_by_fanout, nr_fanout + 1, alloc_fanout);
|
|
nth_midxed_pack_midx_entry(m, perm,
|
|
&entries_by_fanout[nr_fanout],
|
|
cur_object);
|
|
nr_fanout++;
|
|
}
|
|
}
|
|
|
|
for (cur_pack = start_pack; cur_pack < nr_packs; cur_pack++) {
|
|
uint32_t start = 0, end;
|
|
|
|
if (cur_fanout)
|
|
start = get_pack_fanout(p[cur_pack], cur_fanout - 1);
|
|
end = get_pack_fanout(p[cur_pack], cur_fanout);
|
|
|
|
for (cur_object = start; cur_object < end; cur_object++) {
|
|
ALLOC_GROW(entries_by_fanout, nr_fanout + 1, alloc_fanout);
|
|
fill_pack_entry(perm[cur_pack], p[cur_pack], cur_object, &entries_by_fanout[nr_fanout]);
|
|
nr_fanout++;
|
|
}
|
|
}
|
|
|
|
QSORT(entries_by_fanout, nr_fanout, midx_oid_compare);
|
|
|
|
/*
|
|
* The batch is now sorted by OID and then mtime (descending).
|
|
* Take only the first duplicate.
|
|
*/
|
|
for (cur_object = 0; cur_object < nr_fanout; cur_object++) {
|
|
if (cur_object && oideq(&entries_by_fanout[cur_object - 1].oid,
|
|
&entries_by_fanout[cur_object].oid))
|
|
continue;
|
|
|
|
ALLOC_GROW(deduplicated_entries, *nr_objects + 1, alloc_objects);
|
|
memcpy(&deduplicated_entries[*nr_objects],
|
|
&entries_by_fanout[cur_object],
|
|
sizeof(struct pack_midx_entry));
|
|
(*nr_objects)++;
|
|
}
|
|
}
|
|
|
|
free(entries_by_fanout);
|
|
return deduplicated_entries;
|
|
}
|
|
|
|
static size_t write_midx_pack_names(struct hashfile *f,
|
|
char **pack_names,
|
|
uint32_t num_packs)
|
|
{
|
|
uint32_t i;
|
|
unsigned char padding[MIDX_CHUNK_ALIGNMENT];
|
|
size_t written = 0;
|
|
|
|
for (i = 0; i < num_packs; i++) {
|
|
size_t writelen = strlen(pack_names[i]) + 1;
|
|
|
|
if (i && strcmp(pack_names[i], pack_names[i - 1]) <= 0)
|
|
BUG("incorrect pack-file order: %s before %s",
|
|
pack_names[i - 1],
|
|
pack_names[i]);
|
|
|
|
hashwrite(f, pack_names[i], writelen);
|
|
written += writelen;
|
|
}
|
|
|
|
/* add padding to be aligned */
|
|
i = MIDX_CHUNK_ALIGNMENT - (written % MIDX_CHUNK_ALIGNMENT);
|
|
if (i < MIDX_CHUNK_ALIGNMENT) {
|
|
memset(padding, 0, sizeof(padding));
|
|
hashwrite(f, padding, i);
|
|
written += i;
|
|
}
|
|
|
|
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)
|
|
{
|
|
struct pack_midx_entry *list = objects;
|
|
uint32_t i;
|
|
size_t written = 0;
|
|
|
|
for (i = 0; i < nr_objects; i++) {
|
|
struct pack_midx_entry *obj = list++;
|
|
|
|
if (i < nr_objects - 1) {
|
|
struct pack_midx_entry *next = list;
|
|
if (oidcmp(&obj->oid, &next->oid) >= 0)
|
|
BUG("OIDs not in order: %s >= %s",
|
|
oid_to_hex(&obj->oid),
|
|
oid_to_hex(&next->oid));
|
|
}
|
|
|
|
hashwrite(f, obj->oid.hash, (int)hash_len);
|
|
written += hash_len;
|
|
}
|
|
|
|
return written;
|
|
}
|
|
|
|
static size_t write_midx_object_offsets(struct hashfile *f, int large_offset_needed,
|
|
struct pack_midx_entry *objects, uint32_t nr_objects)
|
|
{
|
|
struct pack_midx_entry *list = objects;
|
|
uint32_t i, nr_large_offset = 0;
|
|
size_t written = 0;
|
|
|
|
for (i = 0; i < nr_objects; i++) {
|
|
struct pack_midx_entry *obj = list++;
|
|
|
|
hashwrite_be32(f, obj->pack_int_id);
|
|
|
|
if (large_offset_needed && obj->offset >> 31)
|
|
hashwrite_be32(f, MIDX_LARGE_OFFSET_NEEDED | nr_large_offset++);
|
|
else if (!large_offset_needed && obj->offset >> 32)
|
|
BUG("object %s requires a large offset (%"PRIx64") but the MIDX is not writing large offsets!",
|
|
oid_to_hex(&obj->oid),
|
|
obj->offset);
|
|
else
|
|
hashwrite_be32(f, (uint32_t)obj->offset);
|
|
|
|
written += MIDX_CHUNK_OFFSET_WIDTH;
|
|
}
|
|
|
|
return written;
|
|
}
|
|
|
|
static size_t write_midx_large_offsets(struct hashfile *f, uint32_t nr_large_offset,
|
|
struct pack_midx_entry *objects, uint32_t nr_objects)
|
|
{
|
|
struct pack_midx_entry *list = objects, *end = objects + nr_objects;
|
|
size_t written = 0;
|
|
|
|
while (nr_large_offset) {
|
|
struct pack_midx_entry *obj;
|
|
uint64_t offset;
|
|
|
|
if (list >= end)
|
|
BUG("too many large-offset objects");
|
|
|
|
obj = list++;
|
|
offset = obj->offset;
|
|
|
|
if (!(offset >> 31))
|
|
continue;
|
|
|
|
hashwrite_be32(f, offset >> 32);
|
|
hashwrite_be32(f, offset & 0xffffffffUL);
|
|
written += 2 * sizeof(uint32_t);
|
|
|
|
nr_large_offset--;
|
|
}
|
|
|
|
return written;
|
|
}
|
|
|
|
int write_midx_file(const char *object_dir)
|
|
{
|
|
unsigned char cur_chunk, num_chunks = 0;
|
|
char *midx_name;
|
|
uint32_t i;
|
|
struct hashfile *f = NULL;
|
|
struct lock_file lk;
|
|
struct pack_list packs;
|
|
uint32_t *pack_perm = NULL;
|
|
uint64_t written = 0;
|
|
uint32_t chunk_ids[MIDX_MAX_CHUNKS + 1];
|
|
uint64_t chunk_offsets[MIDX_MAX_CHUNKS + 1];
|
|
uint32_t nr_entries, num_large_offsets = 0;
|
|
struct pack_midx_entry *entries = NULL;
|
|
int large_offsets_needed = 0;
|
|
|
|
midx_name = get_midx_filename(object_dir);
|
|
if (safe_create_leading_directories(midx_name)) {
|
|
UNLEAK(midx_name);
|
|
die_errno(_("unable to create leading directories of %s"),
|
|
midx_name);
|
|
}
|
|
|
|
packs.m = load_multi_pack_index(object_dir, 1);
|
|
|
|
packs.nr = 0;
|
|
packs.alloc_list = packs.m ? packs.m->num_packs : 16;
|
|
packs.alloc_names = packs.alloc_list;
|
|
packs.list = NULL;
|
|
packs.names = NULL;
|
|
packs.pack_name_concat_len = 0;
|
|
ALLOC_ARRAY(packs.list, packs.alloc_list);
|
|
ALLOC_ARRAY(packs.names, packs.alloc_names);
|
|
|
|
if (packs.m) {
|
|
for (i = 0; i < packs.m->num_packs; i++) {
|
|
ALLOC_GROW(packs.list, packs.nr + 1, packs.alloc_list);
|
|
ALLOC_GROW(packs.names, packs.nr + 1, packs.alloc_names);
|
|
|
|
packs.list[packs.nr] = NULL;
|
|
packs.names[packs.nr] = xstrdup(packs.m->pack_names[i]);
|
|
packs.pack_name_concat_len += strlen(packs.names[packs.nr]) + 1;
|
|
packs.nr++;
|
|
}
|
|
}
|
|
|
|
for_each_file_in_pack_dir(object_dir, add_pack_to_midx, &packs);
|
|
|
|
if (packs.m && packs.nr == packs.m->num_packs)
|
|
goto cleanup;
|
|
|
|
if (packs.pack_name_concat_len % MIDX_CHUNK_ALIGNMENT)
|
|
packs.pack_name_concat_len += MIDX_CHUNK_ALIGNMENT -
|
|
(packs.pack_name_concat_len % MIDX_CHUNK_ALIGNMENT);
|
|
|
|
ALLOC_ARRAY(pack_perm, packs.nr);
|
|
sort_packs_by_name(packs.names, packs.nr, pack_perm);
|
|
|
|
entries = get_sorted_entries(packs.m, packs.list, pack_perm, packs.nr, &nr_entries);
|
|
|
|
for (i = 0; i < nr_entries; i++) {
|
|
if (entries[i].offset > 0x7fffffff)
|
|
num_large_offsets++;
|
|
if (entries[i].offset > 0xffffffff)
|
|
large_offsets_needed = 1;
|
|
}
|
|
|
|
hold_lock_file_for_update(&lk, midx_name, LOCK_DIE_ON_ERROR);
|
|
f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
|
|
FREE_AND_NULL(midx_name);
|
|
|
|
if (packs.m)
|
|
close_midx(packs.m);
|
|
|
|
cur_chunk = 0;
|
|
num_chunks = large_offsets_needed ? 5 : 4;
|
|
|
|
written = write_midx_header(f, num_chunks, packs.nr);
|
|
|
|
chunk_ids[cur_chunk] = MIDX_CHUNKID_PACKNAMES;
|
|
chunk_offsets[cur_chunk] = written + (num_chunks + 1) * MIDX_CHUNKLOOKUP_WIDTH;
|
|
|
|
cur_chunk++;
|
|
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] = MIDX_CHUNKID_OBJECTOFFSETS;
|
|
chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + nr_entries * MIDX_HASH_LEN;
|
|
|
|
cur_chunk++;
|
|
chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] + nr_entries * MIDX_CHUNK_OFFSET_WIDTH;
|
|
if (large_offsets_needed) {
|
|
chunk_ids[cur_chunk] = MIDX_CHUNKID_LARGEOFFSETS;
|
|
|
|
cur_chunk++;
|
|
chunk_offsets[cur_chunk] = chunk_offsets[cur_chunk - 1] +
|
|
num_large_offsets * MIDX_CHUNK_LARGE_OFFSET_WIDTH;
|
|
}
|
|
|
|
chunk_ids[cur_chunk] = 0;
|
|
|
|
for (i = 0; i <= num_chunks; i++) {
|
|
if (i && chunk_offsets[i] < chunk_offsets[i - 1])
|
|
BUG("incorrect chunk offsets: %"PRIu64" before %"PRIu64,
|
|
chunk_offsets[i - 1],
|
|
chunk_offsets[i]);
|
|
|
|
if (chunk_offsets[i] % MIDX_CHUNK_ALIGNMENT)
|
|
BUG("chunk offset %"PRIu64" is not properly aligned",
|
|
chunk_offsets[i]);
|
|
|
|
hashwrite_be32(f, chunk_ids[i]);
|
|
hashwrite_be32(f, chunk_offsets[i] >> 32);
|
|
hashwrite_be32(f, chunk_offsets[i]);
|
|
|
|
written += MIDX_CHUNKLOOKUP_WIDTH;
|
|
}
|
|
|
|
for (i = 0; i < num_chunks; i++) {
|
|
if (written != chunk_offsets[i])
|
|
BUG("incorrect chunk offset (%"PRIu64" != %"PRIu64") for chunk id %"PRIx32,
|
|
chunk_offsets[i],
|
|
written,
|
|
chunk_ids[i]);
|
|
|
|
switch (chunk_ids[i]) {
|
|
case MIDX_CHUNKID_PACKNAMES:
|
|
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;
|
|
|
|
case MIDX_CHUNKID_OBJECTOFFSETS:
|
|
written += write_midx_object_offsets(f, large_offsets_needed, entries, nr_entries);
|
|
break;
|
|
|
|
case MIDX_CHUNKID_LARGEOFFSETS:
|
|
written += write_midx_large_offsets(f, num_large_offsets, entries, nr_entries);
|
|
break;
|
|
|
|
default:
|
|
BUG("trying to write unknown chunk id %"PRIx32,
|
|
chunk_ids[i]);
|
|
}
|
|
}
|
|
|
|
if (written != chunk_offsets[num_chunks])
|
|
BUG("incorrect final offset %"PRIu64" != %"PRIu64,
|
|
written,
|
|
chunk_offsets[num_chunks]);
|
|
|
|
finalize_hashfile(f, NULL, CSUM_FSYNC | CSUM_HASH_IN_STREAM);
|
|
commit_lock_file(&lk);
|
|
|
|
cleanup:
|
|
for (i = 0; i < packs.nr; i++) {
|
|
if (packs.list[i]) {
|
|
close_pack(packs.list[i]);
|
|
free(packs.list[i]);
|
|
}
|
|
free(packs.names[i]);
|
|
}
|
|
|
|
free(packs.list);
|
|
free(packs.names);
|
|
free(entries);
|
|
free(pack_perm);
|
|
free(midx_name);
|
|
return 0;
|
|
}
|
|
|
|
void clear_midx_file(struct repository *r)
|
|
{
|
|
char *midx = get_midx_filename(r->objects->odb->path);
|
|
|
|
if (r->objects && r->objects->multi_pack_index) {
|
|
close_midx(r->objects->multi_pack_index);
|
|
r->objects->multi_pack_index = NULL;
|
|
}
|
|
|
|
if (remove_path(midx)) {
|
|
UNLEAK(midx);
|
|
die(_("failed to clear multi-pack-index at %s"), midx);
|
|
}
|
|
|
|
free(midx);
|
|
}
|
|
|
|
static int verify_midx_error;
|
|
|
|
static void midx_report(const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
verify_midx_error = 1;
|
|
va_start(ap, fmt);
|
|
vfprintf(stderr, fmt, ap);
|
|
fprintf(stderr, "\n");
|
|
va_end(ap);
|
|
}
|
|
|
|
struct pair_pos_vs_id
|
|
{
|
|
uint32_t pos;
|
|
uint32_t pack_int_id;
|
|
};
|
|
|
|
static int compare_pair_pos_vs_id(const void *_a, const void *_b)
|
|
{
|
|
struct pair_pos_vs_id *a = (struct pair_pos_vs_id *)_a;
|
|
struct pair_pos_vs_id *b = (struct pair_pos_vs_id *)_b;
|
|
|
|
return b->pack_int_id - a->pack_int_id;
|
|
}
|
|
|
|
/*
|
|
* Limit calls to display_progress() for performance reasons.
|
|
* The interval here was arbitrarily chosen.
|
|
*/
|
|
#define SPARSE_PROGRESS_INTERVAL (1 << 12)
|
|
#define midx_display_sparse_progress(progress, n) \
|
|
do { \
|
|
uint64_t _n = (n); \
|
|
if ((_n & (SPARSE_PROGRESS_INTERVAL - 1)) == 0) \
|
|
display_progress(progress, _n); \
|
|
} while (0)
|
|
|
|
int verify_midx_file(struct repository *r, const char *object_dir)
|
|
{
|
|
struct pair_pos_vs_id *pairs = NULL;
|
|
uint32_t i;
|
|
struct progress *progress;
|
|
struct multi_pack_index *m = load_multi_pack_index(object_dir, 1);
|
|
verify_midx_error = 0;
|
|
|
|
if (!m)
|
|
return 0;
|
|
|
|
progress = start_progress(_("Looking for referenced packfiles"),
|
|
m->num_packs);
|
|
for (i = 0; i < m->num_packs; i++) {
|
|
if (prepare_midx_pack(r, m, i))
|
|
midx_report("failed to load pack in position %d", i);
|
|
|
|
display_progress(progress, i + 1);
|
|
}
|
|
stop_progress(&progress);
|
|
|
|
for (i = 0; i < 255; i++) {
|
|
uint32_t oid_fanout1 = ntohl(m->chunk_oid_fanout[i]);
|
|
uint32_t oid_fanout2 = ntohl(m->chunk_oid_fanout[i + 1]);
|
|
|
|
if (oid_fanout1 > oid_fanout2)
|
|
midx_report(_("oid fanout out of order: fanout[%d] = %"PRIx32" > %"PRIx32" = fanout[%d]"),
|
|
i, oid_fanout1, oid_fanout2, i + 1);
|
|
}
|
|
|
|
progress = start_sparse_progress(_("Verifying OID order in MIDX"),
|
|
m->num_objects - 1);
|
|
for (i = 0; i < m->num_objects - 1; i++) {
|
|
struct object_id oid1, oid2;
|
|
|
|
nth_midxed_object_oid(&oid1, m, i);
|
|
nth_midxed_object_oid(&oid2, m, i + 1);
|
|
|
|
if (oidcmp(&oid1, &oid2) >= 0)
|
|
midx_report(_("oid lookup out of order: oid[%d] = %s >= %s = oid[%d]"),
|
|
i, oid_to_hex(&oid1), oid_to_hex(&oid2), i + 1);
|
|
|
|
midx_display_sparse_progress(progress, i + 1);
|
|
}
|
|
stop_progress(&progress);
|
|
|
|
/*
|
|
* Create an array mapping each object to its packfile id. Sort it
|
|
* to group the objects by packfile. Use this permutation to visit
|
|
* each of the objects and only require 1 packfile to be open at a
|
|
* time.
|
|
*/
|
|
ALLOC_ARRAY(pairs, m->num_objects);
|
|
for (i = 0; i < m->num_objects; i++) {
|
|
pairs[i].pos = i;
|
|
pairs[i].pack_int_id = nth_midxed_pack_int_id(m, i);
|
|
}
|
|
|
|
progress = start_sparse_progress(_("Sorting objects by packfile"),
|
|
m->num_objects);
|
|
display_progress(progress, 0); /* TODO: Measure QSORT() progress */
|
|
QSORT(pairs, m->num_objects, compare_pair_pos_vs_id);
|
|
stop_progress(&progress);
|
|
|
|
progress = start_sparse_progress(_("Verifying object offsets"), m->num_objects);
|
|
for (i = 0; i < m->num_objects; i++) {
|
|
struct object_id oid;
|
|
struct pack_entry e;
|
|
off_t m_offset, p_offset;
|
|
|
|
if (i > 0 && pairs[i-1].pack_int_id != pairs[i].pack_int_id &&
|
|
m->packs[pairs[i-1].pack_int_id])
|
|
{
|
|
close_pack_fd(m->packs[pairs[i-1].pack_int_id]);
|
|
close_pack_index(m->packs[pairs[i-1].pack_int_id]);
|
|
}
|
|
|
|
nth_midxed_object_oid(&oid, m, pairs[i].pos);
|
|
|
|
if (!fill_midx_entry(r, &oid, &e, m)) {
|
|
midx_report(_("failed to load pack entry for oid[%d] = %s"),
|
|
pairs[i].pos, oid_to_hex(&oid));
|
|
continue;
|
|
}
|
|
|
|
if (open_pack_index(e.p)) {
|
|
midx_report(_("failed to load pack-index for packfile %s"),
|
|
e.p->pack_name);
|
|
break;
|
|
}
|
|
|
|
m_offset = e.offset;
|
|
p_offset = find_pack_entry_one(oid.hash, e.p);
|
|
|
|
if (m_offset != p_offset)
|
|
midx_report(_("incorrect object offset for oid[%d] = %s: %"PRIx64" != %"PRIx64),
|
|
pairs[i].pos, oid_to_hex(&oid), m_offset, p_offset);
|
|
|
|
midx_display_sparse_progress(progress, i + 1);
|
|
}
|
|
stop_progress(&progress);
|
|
|
|
free(pairs);
|
|
|
|
return verify_midx_error;
|
|
}
|