git/midx.c
Jeff King c0fe9b2da5 midx: check size of revindex chunk
When we load a revindex from disk, we check the size of the file
compared to the number of objects we expect it to have. But when we use
a RIDX chunk stored directly in the midx, we just access the memory
directly. This can lead to out-of-bounds memory access for a corrupted
or malicious multi-pack-index file.

We can catch this by recording the RIDX chunk size, and then checking it
against the expected size when we "load" the revindex. Note that this
check is much simpler than the one that load_revindex_from_disk() does,
because we just have the data array with no header (so we do not need
to account for the header size, and nor do we need to bother validating
the header values).

The test confirms both that we catch this case, and that we continue the
process (the revindex is required to use the midx bitmaps, but we
fallback to a non-bitmap traversal).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-10-09 15:55:01 -07:00

2137 lines
55 KiB
C

#include "git-compat-util.h"
#include "abspath.h"
#include "config.h"
#include "csum-file.h"
#include "dir.h"
#include "gettext.h"
#include "hex.h"
#include "lockfile.h"
#include "packfile.h"
#include "object-file.h"
#include "object-store-ll.h"
#include "hash-lookup.h"
#include "midx.h"
#include "progress.h"
#include "trace2.h"
#include "run-command.h"
#include "repository.h"
#include "chunk-format.h"
#include "pack.h"
#include "pack-bitmap.h"
#include "refs.h"
#include "revision.h"
#include "list-objects.h"
#define MIDX_SIGNATURE 0x4d494458 /* "MIDX" */
#define MIDX_VERSION 1
#define MIDX_BYTE_FILE_VERSION 4
#define MIDX_BYTE_HASH_VERSION 5
#define MIDX_BYTE_NUM_CHUNKS 6
#define MIDX_BYTE_NUM_PACKS 8
#define MIDX_HEADER_SIZE 12
#define MIDX_MIN_SIZE (MIDX_HEADER_SIZE + the_hash_algo->rawsz)
#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_CHUNKID_OBJECTOFFSETS 0x4f4f4646 /* "OOFF" */
#define MIDX_CHUNKID_LARGEOFFSETS 0x4c4f4646 /* "LOFF" */
#define MIDX_CHUNKID_REVINDEX 0x52494458 /* "RIDX" */
#define MIDX_CHUNK_FANOUT_SIZE (sizeof(uint32_t) * 256)
#define MIDX_CHUNK_OFFSET_WIDTH (2 * sizeof(uint32_t))
#define MIDX_CHUNK_LARGE_OFFSET_WIDTH (sizeof(uint64_t))
#define MIDX_LARGE_OFFSET_NEEDED 0x80000000
#define PACK_EXPIRED UINT_MAX
const unsigned char *get_midx_checksum(struct multi_pack_index *m)
{
return m->data + m->data_len - the_hash_algo->rawsz;
}
void get_midx_filename(struct strbuf *out, const char *object_dir)
{
strbuf_addf(out, "%s/pack/multi-pack-index", object_dir);
}
void get_midx_rev_filename(struct strbuf *out, struct multi_pack_index *m)
{
get_midx_filename(out, m->object_dir);
strbuf_addf(out, "-%s.rev", hash_to_hex(get_midx_checksum(m)));
}
static int midx_read_oid_fanout(const unsigned char *chunk_start,
size_t chunk_size, void *data)
{
struct multi_pack_index *m = data;
m->chunk_oid_fanout = (uint32_t *)chunk_start;
if (chunk_size != 4 * 256) {
error(_("multi-pack-index OID fanout is of the wrong size"));
return 1;
}
m->num_objects = ntohl(m->chunk_oid_fanout[255]);
return 0;
}
static int midx_read_oid_lookup(const unsigned char *chunk_start,
size_t chunk_size, void *data)
{
struct multi_pack_index *m = data;
m->chunk_oid_lookup = chunk_start;
if (chunk_size != st_mult(m->hash_len, m->num_objects)) {
error(_("multi-pack-index OID lookup chunk is the wrong size"));
return 1;
}
return 0;
}
static int midx_read_object_offsets(const unsigned char *chunk_start,
size_t chunk_size, void *data)
{
struct multi_pack_index *m = data;
m->chunk_object_offsets = chunk_start;
if (chunk_size != st_mult(m->num_objects, MIDX_CHUNK_OFFSET_WIDTH)) {
error(_("multi-pack-index object offset chunk is the wrong size"));
return 1;
}
return 0;
}
struct multi_pack_index *load_multi_pack_index(const char *object_dir, int local)
{
struct multi_pack_index *m = NULL;
int fd;
struct stat st;
size_t midx_size;
void *midx_map = NULL;
uint32_t hash_version;
struct strbuf midx_name = STRBUF_INIT;
uint32_t i;
const char *cur_pack_name;
struct chunkfile *cf = NULL;
get_midx_filename(&midx_name, object_dir);
fd = git_open(midx_name.buf);
if (fd < 0)
goto cleanup_fail;
if (fstat(fd, &st)) {
error_errno(_("failed to read %s"), midx_name.buf);
goto cleanup_fail;
}
midx_size = xsize_t(st.st_size);
if (midx_size < MIDX_MIN_SIZE) {
error(_("multi-pack-index file %s is too small"), midx_name.buf);
goto cleanup_fail;
}
strbuf_release(&midx_name);
midx_map = xmmap(NULL, midx_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
FLEX_ALLOC_STR(m, object_dir, object_dir);
m->data = midx_map;
m->data_len = midx_size;
m->local = local;
m->signature = get_be32(m->data);
if (m->signature != MIDX_SIGNATURE)
die(_("multi-pack-index signature 0x%08x does not match signature 0x%08x"),
m->signature, MIDX_SIGNATURE);
m->version = m->data[MIDX_BYTE_FILE_VERSION];
if (m->version != MIDX_VERSION)
die(_("multi-pack-index version %d not recognized"),
m->version);
hash_version = m->data[MIDX_BYTE_HASH_VERSION];
if (hash_version != oid_version(the_hash_algo)) {
error(_("multi-pack-index hash version %u does not match version %u"),
hash_version, oid_version(the_hash_algo));
goto cleanup_fail;
}
m->hash_len = the_hash_algo->rawsz;
m->num_chunks = m->data[MIDX_BYTE_NUM_CHUNKS];
m->num_packs = get_be32(m->data + MIDX_BYTE_NUM_PACKS);
cf = init_chunkfile(NULL);
if (read_table_of_contents(cf, m->data, midx_size,
MIDX_HEADER_SIZE, m->num_chunks,
MIDX_CHUNK_ALIGNMENT))
goto cleanup_fail;
if (pair_chunk(cf, MIDX_CHUNKID_PACKNAMES, &m->chunk_pack_names, &m->chunk_pack_names_len))
die(_("multi-pack-index required pack-name chunk missing or corrupted"));
if (read_chunk(cf, MIDX_CHUNKID_OIDFANOUT, midx_read_oid_fanout, m))
die(_("multi-pack-index required OID fanout chunk missing or corrupted"));
if (read_chunk(cf, MIDX_CHUNKID_OIDLOOKUP, midx_read_oid_lookup, m))
die(_("multi-pack-index required OID lookup chunk missing or corrupted"));
if (read_chunk(cf, MIDX_CHUNKID_OBJECTOFFSETS, midx_read_object_offsets, m))
die(_("multi-pack-index required object offsets chunk missing or corrupted"));
pair_chunk(cf, MIDX_CHUNKID_LARGEOFFSETS, &m->chunk_large_offsets,
&m->chunk_large_offsets_len);
if (git_env_bool("GIT_TEST_MIDX_READ_RIDX", 1))
pair_chunk(cf, MIDX_CHUNKID_REVINDEX, &m->chunk_revindex,
&m->chunk_revindex_len);
CALLOC_ARRAY(m->pack_names, m->num_packs);
CALLOC_ARRAY(m->packs, m->num_packs);
cur_pack_name = (const char *)m->chunk_pack_names;
for (i = 0; i < m->num_packs; i++) {
const char *end;
size_t avail = m->chunk_pack_names_len -
(cur_pack_name - (const char *)m->chunk_pack_names);
m->pack_names[i] = cur_pack_name;
end = memchr(cur_pack_name, '\0', avail);
if (!end)
die(_("multi-pack-index pack-name chunk is too short"));
cur_pack_name = end + 1;
if (i && strcmp(m->pack_names[i], m->pack_names[i - 1]) <= 0)
die(_("multi-pack-index pack names out of order: '%s' before '%s'"),
m->pack_names[i - 1],
m->pack_names[i]);
}
trace2_data_intmax("midx", the_repository, "load/num_packs", m->num_packs);
trace2_data_intmax("midx", the_repository, "load/num_objects", m->num_objects);
free_chunkfile(cf);
return m;
cleanup_fail:
free(m);
strbuf_release(&midx_name);
free_chunkfile(cf);
if (midx_map)
munmap(midx_map, midx_size);
if (0 <= fd)
close(fd);
return NULL;
}
void close_midx(struct multi_pack_index *m)
{
uint32_t i;
if (!m)
return;
close_midx(m->next);
munmap((unsigned char *)m->data, m->data_len);
for (i = 0; i < m->num_packs; i++) {
if (m->packs[i])
m->packs[i]->multi_pack_index = 0;
}
FREE_AND_NULL(m->packs);
FREE_AND_NULL(m->pack_names);
free(m);
}
int prepare_midx_pack(struct repository *r, struct multi_pack_index *m, uint32_t pack_int_id)
{
struct strbuf pack_name = STRBUF_INIT;
struct packed_git *p;
if (pack_int_id >= m->num_packs)
die(_("bad pack-int-id: %u (%u total packs)"),
pack_int_id, m->num_packs);
if (m->packs[pack_int_id])
return 0;
strbuf_addf(&pack_name, "%s/pack/%s", m->object_dir,
m->pack_names[pack_int_id]);
p = add_packed_git(pack_name.buf, pack_name.len, m->local);
strbuf_release(&pack_name);
if (!p)
return 1;
p->multi_pack_index = 1;
m->packs[pack_int_id] = p;
install_packed_git(r, p);
list_add_tail(&p->mru, &r->objects->packed_git_mru);
return 0;
}
int bsearch_midx(const struct object_id *oid, struct multi_pack_index *m, uint32_t *result)
{
return bsearch_hash(oid->hash, m->chunk_oid_fanout, m->chunk_oid_lookup,
the_hash_algo->rawsz, result);
}
struct object_id *nth_midxed_object_oid(struct object_id *oid,
struct multi_pack_index *m,
uint32_t n)
{
if (n >= m->num_objects)
return NULL;
oidread(oid, m->chunk_oid_lookup + st_mult(m->hash_len, n));
return oid;
}
off_t nth_midxed_offset(struct multi_pack_index *m, uint32_t pos)
{
const unsigned char *offset_data;
uint32_t offset32;
offset_data = m->chunk_object_offsets + (off_t)pos * MIDX_CHUNK_OFFSET_WIDTH;
offset32 = get_be32(offset_data + sizeof(uint32_t));
if (m->chunk_large_offsets && offset32 & MIDX_LARGE_OFFSET_NEEDED) {
if (sizeof(off_t) < sizeof(uint64_t))
die(_("multi-pack-index stores a 64-bit offset, but off_t is too small"));
offset32 ^= MIDX_LARGE_OFFSET_NEEDED;
if (offset32 >= m->chunk_large_offsets_len / sizeof(uint64_t))
die(_("multi-pack-index large offset out of bounds"));
return get_be64(m->chunk_large_offsets + sizeof(uint64_t) * offset32);
}
return offset32;
}
uint32_t nth_midxed_pack_int_id(struct multi_pack_index *m, uint32_t pos)
{
return get_be32(m->chunk_object_offsets +
(off_t)pos * MIDX_CHUNK_OFFSET_WIDTH);
}
int fill_midx_entry(struct repository *r,
const struct object_id *oid,
struct pack_entry *e,
struct multi_pack_index *m)
{
uint32_t pos;
uint32_t pack_int_id;
struct packed_git *p;
if (!bsearch_midx(oid, m, &pos))
return 0;
if (pos >= m->num_objects)
return 0;
pack_int_id = nth_midxed_pack_int_id(m, pos);
if (prepare_midx_pack(r, m, pack_int_id))
return 0;
p = m->packs[pack_int_id];
/*
* We are about to tell the caller where they can locate the
* requested object. We better make sure the packfile is
* still here and can be accessed before supplying that
* answer, as it may have been deleted since the MIDX was
* loaded!
*/
if (!is_pack_valid(p))
return 0;
if (oidset_size(&p->bad_objects) &&
oidset_contains(&p->bad_objects, oid))
return 0;
e->offset = nth_midxed_offset(m, pos);
e->p = p;
return 1;
}
/* Match "foo.idx" against either "foo.pack" _or_ "foo.idx". */
static int cmp_idx_or_pack_name(const char *idx_or_pack_name,
const char *idx_name)
{
/* Skip past any initial matching prefix. */
while (*idx_name && *idx_name == *idx_or_pack_name) {
idx_name++;
idx_or_pack_name++;
}
/*
* If we didn't match completely, we may have matched "pack-1234." and
* be left with "idx" and "pack" respectively, which is also OK. We do
* not have to check for "idx" and "idx", because that would have been
* a complete match (and in that case these strcmps will be false, but
* we'll correctly return 0 from the final strcmp() below.
*
* Technically this matches "fooidx" and "foopack", but we'd never have
* such names in the first place.
*/
if (!strcmp(idx_name, "idx") && !strcmp(idx_or_pack_name, "pack"))
return 0;
/*
* This not only checks for a complete match, but also orders based on
* the first non-identical character, which means our ordering will
* match a raw strcmp(). That makes it OK to use this to binary search
* a naively-sorted list.
*/
return strcmp(idx_or_pack_name, idx_name);
}
int midx_contains_pack(struct multi_pack_index *m, const char *idx_or_pack_name)
{
uint32_t first = 0, last = m->num_packs;
while (first < last) {
uint32_t mid = first + (last - first) / 2;
const char *current;
int cmp;
current = m->pack_names[mid];
cmp = cmp_idx_or_pack_name(idx_or_pack_name, current);
if (!cmp)
return 1;
if (cmp > 0) {
first = mid + 1;
continue;
}
last = mid;
}
return 0;
}
int prepare_multi_pack_index_one(struct repository *r, const char *object_dir, int local)
{
struct multi_pack_index *m;
struct multi_pack_index *m_search;
prepare_repo_settings(r);
if (!r->settings.core_multi_pack_index)
return 0;
for (m_search = r->objects->multi_pack_index; m_search; m_search = m_search->next)
if (!strcmp(object_dir, m_search->object_dir))
return 1;
m = load_multi_pack_index(object_dir, local);
if (m) {
struct multi_pack_index *mp = r->objects->multi_pack_index;
if (mp) {
m->next = mp->next;
mp->next = m;
} else
r->objects->multi_pack_index = m;
return 1;
}
return 0;
}
static size_t write_midx_header(struct hashfile *f,
unsigned char num_chunks,
uint32_t num_packs)
{
hashwrite_be32(f, MIDX_SIGNATURE);
hashwrite_u8(f, MIDX_VERSION);
hashwrite_u8(f, oid_version(the_hash_algo));
hashwrite_u8(f, num_chunks);
hashwrite_u8(f, 0); /* unused */
hashwrite_be32(f, num_packs);
return MIDX_HEADER_SIZE;
}
struct pack_info {
uint32_t orig_pack_int_id;
char *pack_name;
struct packed_git *p;
unsigned expired : 1;
};
static int pack_info_compare(const void *_a, const void *_b)
{
struct pack_info *a = (struct pack_info *)_a;
struct pack_info *b = (struct pack_info *)_b;
return strcmp(a->pack_name, b->pack_name);
}
static int idx_or_pack_name_cmp(const void *_va, const void *_vb)
{
const char *pack_name = _va;
const struct pack_info *compar = _vb;
return cmp_idx_or_pack_name(pack_name, compar->pack_name);
}
struct write_midx_context {
struct pack_info *info;
size_t nr;
size_t alloc;
struct multi_pack_index *m;
struct progress *progress;
unsigned pack_paths_checked;
struct pack_midx_entry *entries;
size_t entries_nr;
uint32_t *pack_perm;
uint32_t *pack_order;
unsigned large_offsets_needed:1;
uint32_t num_large_offsets;
int preferred_pack_idx;
struct string_list *to_include;
};
static void add_pack_to_midx(const char *full_path, size_t full_path_len,
const char *file_name, void *data)
{
struct write_midx_context *ctx = data;
if (ends_with(file_name, ".idx")) {
display_progress(ctx->progress, ++ctx->pack_paths_checked);
/*
* Note that at most one of ctx->m and ctx->to_include are set,
* so we are testing midx_contains_pack() and
* string_list_has_string() independently (guarded by the
* appropriate NULL checks).
*
* We could support passing to_include while reusing an existing
* MIDX, but don't currently since the reuse process drags
* forward all packs from an existing MIDX (without checking
* whether or not they appear in the to_include list).
*
* If we added support for that, these next two conditional
* should be performed independently (likely checking
* to_include before the existing MIDX).
*/
if (ctx->m && midx_contains_pack(ctx->m, file_name))
return;
else if (ctx->to_include &&
!string_list_has_string(ctx->to_include, file_name))
return;
ALLOC_GROW(ctx->info, ctx->nr + 1, ctx->alloc);
ctx->info[ctx->nr].p = add_packed_git(full_path,
full_path_len,
0);
if (!ctx->info[ctx->nr].p) {
warning(_("failed to add packfile '%s'"),
full_path);
return;
}
if (open_pack_index(ctx->info[ctx->nr].p)) {
warning(_("failed to open pack-index '%s'"),
full_path);
close_pack(ctx->info[ctx->nr].p);
FREE_AND_NULL(ctx->info[ctx->nr].p);
return;
}
ctx->info[ctx->nr].pack_name = xstrdup(file_name);
ctx->info[ctx->nr].orig_pack_int_id = ctx->nr;
ctx->info[ctx->nr].expired = 0;
ctx->nr++;
}
}
struct pack_midx_entry {
struct object_id oid;
uint32_t pack_int_id;
time_t pack_mtime;
uint64_t offset;
unsigned preferred : 1;
};
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;
/* Sort objects in a preferred pack first when multiple copies exist. */
if (a->preferred > b->preferred)
return -1;
if (a->preferred < b->preferred)
return 1;
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,
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 = 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,
int preferred)
{
if (nth_packed_object_id(&entry->oid, p, cur_object) < 0)
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);
entry->preferred = !!preferred;
}
struct midx_fanout {
struct pack_midx_entry *entries;
size_t nr, alloc;
};
static void midx_fanout_grow(struct midx_fanout *fanout, size_t nr)
{
if (nr < fanout->nr)
BUG("negative growth in midx_fanout_grow() (%"PRIuMAX" < %"PRIuMAX")",
(uintmax_t)nr, (uintmax_t)fanout->nr);
ALLOC_GROW(fanout->entries, nr, fanout->alloc);
}
static void midx_fanout_sort(struct midx_fanout *fanout)
{
QSORT(fanout->entries, fanout->nr, midx_oid_compare);
}
static void midx_fanout_add_midx_fanout(struct midx_fanout *fanout,
struct multi_pack_index *m,
uint32_t cur_fanout,
int preferred_pack)
{
uint32_t start = 0, end;
uint32_t cur_object;
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++) {
if ((preferred_pack > -1) &&
(preferred_pack == nth_midxed_pack_int_id(m, cur_object))) {
/*
* Objects from preferred packs are added
* separately.
*/
continue;
}
midx_fanout_grow(fanout, fanout->nr + 1);
nth_midxed_pack_midx_entry(m,
&fanout->entries[fanout->nr],
cur_object);
fanout->entries[fanout->nr].preferred = 0;
fanout->nr++;
}
}
static void midx_fanout_add_pack_fanout(struct midx_fanout *fanout,
struct pack_info *info,
uint32_t cur_pack,
int preferred,
uint32_t cur_fanout)
{
struct packed_git *pack = info[cur_pack].p;
uint32_t start = 0, end;
uint32_t cur_object;
if (cur_fanout)
start = get_pack_fanout(pack, cur_fanout - 1);
end = get_pack_fanout(pack, cur_fanout);
for (cur_object = start; cur_object < end; cur_object++) {
midx_fanout_grow(fanout, fanout->nr + 1);
fill_pack_entry(cur_pack,
info[cur_pack].p,
cur_object,
&fanout->entries[fanout->nr],
preferred);
fanout->nr++;
}
}
/*
* 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 pack_info *info,
uint32_t nr_packs,
size_t *nr_objects,
int preferred_pack)
{
uint32_t cur_fanout, cur_pack, cur_object;
size_t alloc_objects, total_objects = 0;
struct midx_fanout fanout = { 0 };
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 = st_add(total_objects,
info[cur_pack].p->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 = fanout.alloc = total_objects > 3200 ? total_objects / 200 : 16;
ALLOC_ARRAY(fanout.entries, fanout.alloc);
ALLOC_ARRAY(deduplicated_entries, alloc_objects);
*nr_objects = 0;
for (cur_fanout = 0; cur_fanout < 256; cur_fanout++) {
fanout.nr = 0;
if (m)
midx_fanout_add_midx_fanout(&fanout, m, cur_fanout,
preferred_pack);
for (cur_pack = start_pack; cur_pack < nr_packs; cur_pack++) {
int preferred = cur_pack == preferred_pack;
midx_fanout_add_pack_fanout(&fanout,
info, cur_pack,
preferred, cur_fanout);
}
if (-1 < preferred_pack && preferred_pack < start_pack)
midx_fanout_add_pack_fanout(&fanout, info,
preferred_pack, 1,
cur_fanout);
midx_fanout_sort(&fanout);
/*
* The batch is now sorted by OID and then mtime (descending).
* Take only the first duplicate.
*/
for (cur_object = 0; cur_object < fanout.nr; cur_object++) {
if (cur_object && oideq(&fanout.entries[cur_object - 1].oid,
&fanout.entries[cur_object].oid))
continue;
ALLOC_GROW(deduplicated_entries, st_add(*nr_objects, 1),
alloc_objects);
memcpy(&deduplicated_entries[*nr_objects],
&fanout.entries[cur_object],
sizeof(struct pack_midx_entry));
(*nr_objects)++;
}
}
free(fanout.entries);
return deduplicated_entries;
}
static int write_midx_pack_names(struct hashfile *f, void *data)
{
struct write_midx_context *ctx = data;
uint32_t i;
unsigned char padding[MIDX_CHUNK_ALIGNMENT];
size_t written = 0;
for (i = 0; i < ctx->nr; i++) {
size_t writelen;
if (ctx->info[i].expired)
continue;
if (i && strcmp(ctx->info[i].pack_name, ctx->info[i - 1].pack_name) <= 0)
BUG("incorrect pack-file order: %s before %s",
ctx->info[i - 1].pack_name,
ctx->info[i].pack_name);
writelen = strlen(ctx->info[i].pack_name) + 1;
hashwrite(f, ctx->info[i].pack_name, 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);
}
return 0;
}
static int write_midx_oid_fanout(struct hashfile *f,
void *data)
{
struct write_midx_context *ctx = data;
struct pack_midx_entry *list = ctx->entries;
struct pack_midx_entry *last = ctx->entries + ctx->entries_nr;
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 0;
}
static int write_midx_oid_lookup(struct hashfile *f,
void *data)
{
struct write_midx_context *ctx = data;
unsigned char hash_len = the_hash_algo->rawsz;
struct pack_midx_entry *list = ctx->entries;
uint32_t i;
for (i = 0; i < ctx->entries_nr; i++) {
struct pack_midx_entry *obj = list++;
if (i < ctx->entries_nr - 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);
}
return 0;
}
static int write_midx_object_offsets(struct hashfile *f,
void *data)
{
struct write_midx_context *ctx = data;
struct pack_midx_entry *list = ctx->entries;
uint32_t i, nr_large_offset = 0;
for (i = 0; i < ctx->entries_nr; i++) {
struct pack_midx_entry *obj = list++;
if (ctx->pack_perm[obj->pack_int_id] == PACK_EXPIRED)
BUG("object %s is in an expired pack with int-id %d",
oid_to_hex(&obj->oid),
obj->pack_int_id);
hashwrite_be32(f, ctx->pack_perm[obj->pack_int_id]);
if (ctx->large_offsets_needed && obj->offset >> 31)
hashwrite_be32(f, MIDX_LARGE_OFFSET_NEEDED | nr_large_offset++);
else if (!ctx->large_offsets_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);
}
return 0;
}
static int write_midx_large_offsets(struct hashfile *f,
void *data)
{
struct write_midx_context *ctx = data;
struct pack_midx_entry *list = ctx->entries;
struct pack_midx_entry *end = ctx->entries + ctx->entries_nr;
uint32_t nr_large_offset = ctx->num_large_offsets;
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_be64(f, offset);
nr_large_offset--;
}
return 0;
}
static int write_midx_revindex(struct hashfile *f,
void *data)
{
struct write_midx_context *ctx = data;
uint32_t i;
for (i = 0; i < ctx->entries_nr; i++)
hashwrite_be32(f, ctx->pack_order[i]);
return 0;
}
struct midx_pack_order_data {
uint32_t nr;
uint32_t pack;
off_t offset;
};
static int midx_pack_order_cmp(const void *va, const void *vb)
{
const struct midx_pack_order_data *a = va, *b = vb;
if (a->pack < b->pack)
return -1;
else if (a->pack > b->pack)
return 1;
else if (a->offset < b->offset)
return -1;
else if (a->offset > b->offset)
return 1;
else
return 0;
}
static uint32_t *midx_pack_order(struct write_midx_context *ctx)
{
struct midx_pack_order_data *data;
uint32_t *pack_order;
uint32_t i;
trace2_region_enter("midx", "midx_pack_order", the_repository);
ALLOC_ARRAY(data, ctx->entries_nr);
for (i = 0; i < ctx->entries_nr; i++) {
struct pack_midx_entry *e = &ctx->entries[i];
data[i].nr = i;
data[i].pack = ctx->pack_perm[e->pack_int_id];
if (!e->preferred)
data[i].pack |= (1U << 31);
data[i].offset = e->offset;
}
QSORT(data, ctx->entries_nr, midx_pack_order_cmp);
ALLOC_ARRAY(pack_order, ctx->entries_nr);
for (i = 0; i < ctx->entries_nr; i++)
pack_order[i] = data[i].nr;
free(data);
trace2_region_leave("midx", "midx_pack_order", the_repository);
return pack_order;
}
static void write_midx_reverse_index(char *midx_name, unsigned char *midx_hash,
struct write_midx_context *ctx)
{
struct strbuf buf = STRBUF_INIT;
const char *tmp_file;
trace2_region_enter("midx", "write_midx_reverse_index", the_repository);
strbuf_addf(&buf, "%s-%s.rev", midx_name, hash_to_hex(midx_hash));
tmp_file = write_rev_file_order(NULL, ctx->pack_order, ctx->entries_nr,
midx_hash, WRITE_REV);
if (finalize_object_file(tmp_file, buf.buf))
die(_("cannot store reverse index file"));
strbuf_release(&buf);
trace2_region_leave("midx", "write_midx_reverse_index", the_repository);
}
static void clear_midx_files_ext(const char *object_dir, const char *ext,
unsigned char *keep_hash);
static int midx_checksum_valid(struct multi_pack_index *m)
{
return hashfile_checksum_valid(m->data, m->data_len);
}
static void prepare_midx_packing_data(struct packing_data *pdata,
struct write_midx_context *ctx)
{
uint32_t i;
trace2_region_enter("midx", "prepare_midx_packing_data", the_repository);
memset(pdata, 0, sizeof(struct packing_data));
prepare_packing_data(the_repository, pdata);
for (i = 0; i < ctx->entries_nr; i++) {
struct pack_midx_entry *from = &ctx->entries[ctx->pack_order[i]];
struct object_entry *to = packlist_alloc(pdata, &from->oid);
oe_set_in_pack(pdata, to,
ctx->info[ctx->pack_perm[from->pack_int_id]].p);
}
trace2_region_leave("midx", "prepare_midx_packing_data", the_repository);
}
static int add_ref_to_pending(const char *refname,
const struct object_id *oid,
int flag, void *cb_data)
{
struct rev_info *revs = (struct rev_info*)cb_data;
struct object_id peeled;
struct object *object;
if ((flag & REF_ISSYMREF) && (flag & REF_ISBROKEN)) {
warning("symbolic ref is dangling: %s", refname);
return 0;
}
if (!peel_iterated_oid(oid, &peeled))
oid = &peeled;
object = parse_object_or_die(oid, refname);
if (object->type != OBJ_COMMIT)
return 0;
add_pending_object(revs, object, "");
if (bitmap_is_preferred_refname(revs->repo, refname))
object->flags |= NEEDS_BITMAP;
return 0;
}
struct bitmap_commit_cb {
struct commit **commits;
size_t commits_nr, commits_alloc;
struct write_midx_context *ctx;
};
static const struct object_id *bitmap_oid_access(size_t index,
const void *_entries)
{
const struct pack_midx_entry *entries = _entries;
return &entries[index].oid;
}
static void bitmap_show_commit(struct commit *commit, void *_data)
{
struct bitmap_commit_cb *data = _data;
int pos = oid_pos(&commit->object.oid, data->ctx->entries,
data->ctx->entries_nr,
bitmap_oid_access);
if (pos < 0)
return;
ALLOC_GROW(data->commits, data->commits_nr + 1, data->commits_alloc);
data->commits[data->commits_nr++] = commit;
}
static int read_refs_snapshot(const char *refs_snapshot,
struct rev_info *revs)
{
struct strbuf buf = STRBUF_INIT;
struct object_id oid;
FILE *f = xfopen(refs_snapshot, "r");
while (strbuf_getline(&buf, f) != EOF) {
struct object *object;
int preferred = 0;
char *hex = buf.buf;
const char *end = NULL;
if (buf.len && *buf.buf == '+') {
preferred = 1;
hex = &buf.buf[1];
}
if (parse_oid_hex(hex, &oid, &end) < 0)
die(_("could not parse line: %s"), buf.buf);
if (*end)
die(_("malformed line: %s"), buf.buf);
object = parse_object_or_die(&oid, NULL);
if (preferred)
object->flags |= NEEDS_BITMAP;
add_pending_object(revs, object, "");
}
fclose(f);
strbuf_release(&buf);
return 0;
}
static struct commit **find_commits_for_midx_bitmap(uint32_t *indexed_commits_nr_p,
const char *refs_snapshot,
struct write_midx_context *ctx)
{
struct rev_info revs;
struct bitmap_commit_cb cb = {0};
trace2_region_enter("midx", "find_commits_for_midx_bitmap",
the_repository);
cb.ctx = ctx;
repo_init_revisions(the_repository, &revs, NULL);
if (refs_snapshot) {
read_refs_snapshot(refs_snapshot, &revs);
} else {
setup_revisions(0, NULL, &revs, NULL);
for_each_ref(add_ref_to_pending, &revs);
}
/*
* Skipping promisor objects here is intentional, since it only excludes
* them from the list of reachable commits that we want to select from
* when computing the selection of MIDX'd commits to receive bitmaps.
*
* Reachability bitmaps do require that their objects be closed under
* reachability, but fetching any objects missing from promisors at this
* point is too late. But, if one of those objects can be reached from
* an another object that is included in the bitmap, then we will
* complain later that we don't have reachability closure (and fail
* appropriately).
*/
fetch_if_missing = 0;
revs.exclude_promisor_objects = 1;
if (prepare_revision_walk(&revs))
die(_("revision walk setup failed"));
traverse_commit_list(&revs, bitmap_show_commit, NULL, &cb);
if (indexed_commits_nr_p)
*indexed_commits_nr_p = cb.commits_nr;
release_revisions(&revs);
trace2_region_leave("midx", "find_commits_for_midx_bitmap",
the_repository);
return cb.commits;
}
static int write_midx_bitmap(const char *midx_name,
const unsigned char *midx_hash,
struct packing_data *pdata,
struct commit **commits,
uint32_t commits_nr,
uint32_t *pack_order,
unsigned flags)
{
int ret, i;
uint16_t options = 0;
struct pack_idx_entry **index;
char *bitmap_name = xstrfmt("%s-%s.bitmap", midx_name,
hash_to_hex(midx_hash));
trace2_region_enter("midx", "write_midx_bitmap", the_repository);
if (flags & MIDX_WRITE_BITMAP_HASH_CACHE)
options |= BITMAP_OPT_HASH_CACHE;
if (flags & MIDX_WRITE_BITMAP_LOOKUP_TABLE)
options |= BITMAP_OPT_LOOKUP_TABLE;
/*
* Build the MIDX-order index based on pdata.objects (which is already
* in MIDX order; c.f., 'midx_pack_order_cmp()' for the definition of
* this order).
*/
ALLOC_ARRAY(index, pdata->nr_objects);
for (i = 0; i < pdata->nr_objects; i++)
index[i] = &pdata->objects[i].idx;
bitmap_writer_show_progress(flags & MIDX_PROGRESS);
bitmap_writer_build_type_index(pdata, index, pdata->nr_objects);
/*
* bitmap_writer_finish expects objects in lex order, but pack_order
* gives us exactly that. use it directly instead of re-sorting the
* array.
*
* This changes the order of objects in 'index' between
* bitmap_writer_build_type_index and bitmap_writer_finish.
*
* The same re-ordering takes place in the single-pack bitmap code via
* write_idx_file(), which is called by finish_tmp_packfile(), which
* happens between bitmap_writer_build_type_index() and
* bitmap_writer_finish().
*/
for (i = 0; i < pdata->nr_objects; i++)
index[pack_order[i]] = &pdata->objects[i].idx;
bitmap_writer_select_commits(commits, commits_nr, -1);
ret = bitmap_writer_build(pdata);
if (ret < 0)
goto cleanup;
bitmap_writer_set_checksum(midx_hash);
bitmap_writer_finish(index, pdata->nr_objects, bitmap_name, options);
cleanup:
free(index);
free(bitmap_name);
trace2_region_leave("midx", "write_midx_bitmap", the_repository);
return ret;
}
static struct multi_pack_index *lookup_multi_pack_index(struct repository *r,
const char *object_dir)
{
struct multi_pack_index *result = NULL;
struct multi_pack_index *cur;
char *obj_dir_real = real_pathdup(object_dir, 1);
struct strbuf cur_path_real = STRBUF_INIT;
/* Ensure the given object_dir is local, or a known alternate. */
find_odb(r, obj_dir_real);
for (cur = get_multi_pack_index(r); cur; cur = cur->next) {
strbuf_realpath(&cur_path_real, cur->object_dir, 1);
if (!strcmp(obj_dir_real, cur_path_real.buf)) {
result = cur;
goto cleanup;
}
}
cleanup:
free(obj_dir_real);
strbuf_release(&cur_path_real);
return result;
}
static int write_midx_internal(const char *object_dir,
struct string_list *packs_to_include,
struct string_list *packs_to_drop,
const char *preferred_pack_name,
const char *refs_snapshot,
unsigned flags)
{
struct strbuf midx_name = STRBUF_INIT;
unsigned char midx_hash[GIT_MAX_RAWSZ];
uint32_t i;
struct hashfile *f = NULL;
struct lock_file lk;
struct write_midx_context ctx = { 0 };
int pack_name_concat_len = 0;
int dropped_packs = 0;
int result = 0;
struct chunkfile *cf;
trace2_region_enter("midx", "write_midx_internal", the_repository);
get_midx_filename(&midx_name, object_dir);
if (safe_create_leading_directories(midx_name.buf))
die_errno(_("unable to create leading directories of %s"),
midx_name.buf);
if (!packs_to_include) {
/*
* Only reference an existing MIDX when not filtering which
* packs to include, since all packs and objects are copied
* blindly from an existing MIDX if one is present.
*/
ctx.m = lookup_multi_pack_index(the_repository, object_dir);
}
if (ctx.m && !midx_checksum_valid(ctx.m)) {
warning(_("ignoring existing multi-pack-index; checksum mismatch"));
ctx.m = NULL;
}
ctx.nr = 0;
ctx.alloc = ctx.m ? ctx.m->num_packs : 16;
ctx.info = NULL;
ALLOC_ARRAY(ctx.info, ctx.alloc);
if (ctx.m) {
for (i = 0; i < ctx.m->num_packs; i++) {
ALLOC_GROW(ctx.info, ctx.nr + 1, ctx.alloc);
ctx.info[ctx.nr].orig_pack_int_id = i;
ctx.info[ctx.nr].pack_name = xstrdup(ctx.m->pack_names[i]);
ctx.info[ctx.nr].p = ctx.m->packs[i];
ctx.info[ctx.nr].expired = 0;
if (flags & MIDX_WRITE_REV_INDEX) {
/*
* If generating a reverse index, need to have
* packed_git's loaded to compare their
* mtimes and object count.
*/
if (prepare_midx_pack(the_repository, ctx.m, i)) {
error(_("could not load pack"));
result = 1;
goto cleanup;
}
if (open_pack_index(ctx.m->packs[i]))
die(_("could not open index for %s"),
ctx.m->packs[i]->pack_name);
ctx.info[ctx.nr].p = ctx.m->packs[i];
}
ctx.nr++;
}
}
ctx.pack_paths_checked = 0;
if (flags & MIDX_PROGRESS)
ctx.progress = start_delayed_progress(_("Adding packfiles to multi-pack-index"), 0);
else
ctx.progress = NULL;
ctx.to_include = packs_to_include;
for_each_file_in_pack_dir(object_dir, add_pack_to_midx, &ctx);
stop_progress(&ctx.progress);
if ((ctx.m && ctx.nr == ctx.m->num_packs) &&
!(packs_to_include || packs_to_drop)) {
struct bitmap_index *bitmap_git;
int bitmap_exists;
int want_bitmap = flags & MIDX_WRITE_BITMAP;
bitmap_git = prepare_midx_bitmap_git(ctx.m);
bitmap_exists = bitmap_git && bitmap_is_midx(bitmap_git);
free_bitmap_index(bitmap_git);
if (bitmap_exists || !want_bitmap) {
/*
* The correct MIDX already exists, and so does a
* corresponding bitmap (or one wasn't requested).
*/
if (!want_bitmap)
clear_midx_files_ext(object_dir, ".bitmap",
NULL);
goto cleanup;
}
}
if (preferred_pack_name) {
ctx.preferred_pack_idx = -1;
for (i = 0; i < ctx.nr; i++) {
if (!cmp_idx_or_pack_name(preferred_pack_name,
ctx.info[i].pack_name)) {
ctx.preferred_pack_idx = i;
break;
}
}
if (ctx.preferred_pack_idx == -1)
warning(_("unknown preferred pack: '%s'"),
preferred_pack_name);
} else if (ctx.nr &&
(flags & (MIDX_WRITE_REV_INDEX | MIDX_WRITE_BITMAP))) {
struct packed_git *oldest = ctx.info[ctx.preferred_pack_idx].p;
ctx.preferred_pack_idx = 0;
if (packs_to_drop && packs_to_drop->nr)
BUG("cannot write a MIDX bitmap during expiration");
/*
* set a preferred pack when writing a bitmap to ensure that
* the pack from which the first object is selected in pseudo
* pack-order has all of its objects selected from that pack
* (and not another pack containing a duplicate)
*/
for (i = 1; i < ctx.nr; i++) {
struct packed_git *p = ctx.info[i].p;
if (!oldest->num_objects || p->mtime < oldest->mtime) {
oldest = p;
ctx.preferred_pack_idx = i;
}
}
if (!oldest->num_objects) {
/*
* If all packs are empty; unset the preferred index.
* This is acceptable since there will be no duplicate
* objects to resolve, so the preferred value doesn't
* matter.
*/
ctx.preferred_pack_idx = -1;
}
} else {
/*
* otherwise don't mark any pack as preferred to avoid
* interfering with expiration logic below
*/
ctx.preferred_pack_idx = -1;
}
if (ctx.preferred_pack_idx > -1) {
struct packed_git *preferred = ctx.info[ctx.preferred_pack_idx].p;
if (!preferred->num_objects) {
error(_("cannot select preferred pack %s with no objects"),
preferred->pack_name);
result = 1;
goto cleanup;
}
}
ctx.entries = get_sorted_entries(ctx.m, ctx.info, ctx.nr, &ctx.entries_nr,
ctx.preferred_pack_idx);
ctx.large_offsets_needed = 0;
for (i = 0; i < ctx.entries_nr; i++) {
if (ctx.entries[i].offset > 0x7fffffff)
ctx.num_large_offsets++;
if (ctx.entries[i].offset > 0xffffffff)
ctx.large_offsets_needed = 1;
}
QSORT(ctx.info, ctx.nr, pack_info_compare);
if (packs_to_drop && packs_to_drop->nr) {
int drop_index = 0;
int missing_drops = 0;
for (i = 0; i < ctx.nr && drop_index < packs_to_drop->nr; i++) {
int cmp = strcmp(ctx.info[i].pack_name,
packs_to_drop->items[drop_index].string);
if (!cmp) {
drop_index++;
ctx.info[i].expired = 1;
} else if (cmp > 0) {
error(_("did not see pack-file %s to drop"),
packs_to_drop->items[drop_index].string);
drop_index++;
missing_drops++;
i--;
} else {
ctx.info[i].expired = 0;
}
}
if (missing_drops) {
result = 1;
goto cleanup;
}
}
/*
* pack_perm stores a permutation between pack-int-ids from the
* previous multi-pack-index to the new one we are writing:
*
* pack_perm[old_id] = new_id
*/
ALLOC_ARRAY(ctx.pack_perm, ctx.nr);
for (i = 0; i < ctx.nr; i++) {
if (ctx.info[i].expired) {
dropped_packs++;
ctx.pack_perm[ctx.info[i].orig_pack_int_id] = PACK_EXPIRED;
} else {
ctx.pack_perm[ctx.info[i].orig_pack_int_id] = i - dropped_packs;
}
}
for (i = 0; i < ctx.nr; i++) {
if (!ctx.info[i].expired)
pack_name_concat_len += strlen(ctx.info[i].pack_name) + 1;
}
/* Check that the preferred pack wasn't expired (if given). */
if (preferred_pack_name) {
struct pack_info *preferred = bsearch(preferred_pack_name,
ctx.info, ctx.nr,
sizeof(*ctx.info),
idx_or_pack_name_cmp);
if (preferred) {
uint32_t perm = ctx.pack_perm[preferred->orig_pack_int_id];
if (perm == PACK_EXPIRED)
warning(_("preferred pack '%s' is expired"),
preferred_pack_name);
}
}
if (pack_name_concat_len % MIDX_CHUNK_ALIGNMENT)
pack_name_concat_len += MIDX_CHUNK_ALIGNMENT -
(pack_name_concat_len % MIDX_CHUNK_ALIGNMENT);
hold_lock_file_for_update(&lk, midx_name.buf, LOCK_DIE_ON_ERROR);
f = hashfd(get_lock_file_fd(&lk), get_lock_file_path(&lk));
if (ctx.nr - dropped_packs == 0) {
error(_("no pack files to index."));
result = 1;
goto cleanup;
}
if (!ctx.entries_nr) {
if (flags & MIDX_WRITE_BITMAP)
warning(_("refusing to write multi-pack .bitmap without any objects"));
flags &= ~(MIDX_WRITE_REV_INDEX | MIDX_WRITE_BITMAP);
}
cf = init_chunkfile(f);
add_chunk(cf, MIDX_CHUNKID_PACKNAMES, pack_name_concat_len,
write_midx_pack_names);
add_chunk(cf, MIDX_CHUNKID_OIDFANOUT, MIDX_CHUNK_FANOUT_SIZE,
write_midx_oid_fanout);
add_chunk(cf, MIDX_CHUNKID_OIDLOOKUP,
st_mult(ctx.entries_nr, the_hash_algo->rawsz),
write_midx_oid_lookup);
add_chunk(cf, MIDX_CHUNKID_OBJECTOFFSETS,
st_mult(ctx.entries_nr, MIDX_CHUNK_OFFSET_WIDTH),
write_midx_object_offsets);
if (ctx.large_offsets_needed)
add_chunk(cf, MIDX_CHUNKID_LARGEOFFSETS,
st_mult(ctx.num_large_offsets,
MIDX_CHUNK_LARGE_OFFSET_WIDTH),
write_midx_large_offsets);
if (flags & (MIDX_WRITE_REV_INDEX | MIDX_WRITE_BITMAP)) {
ctx.pack_order = midx_pack_order(&ctx);
add_chunk(cf, MIDX_CHUNKID_REVINDEX,
st_mult(ctx.entries_nr, sizeof(uint32_t)),
write_midx_revindex);
}
write_midx_header(f, get_num_chunks(cf), ctx.nr - dropped_packs);
write_chunkfile(cf, &ctx);
finalize_hashfile(f, midx_hash, FSYNC_COMPONENT_PACK_METADATA,
CSUM_FSYNC | CSUM_HASH_IN_STREAM);
free_chunkfile(cf);
if (flags & MIDX_WRITE_REV_INDEX &&
git_env_bool("GIT_TEST_MIDX_WRITE_REV", 0))
write_midx_reverse_index(midx_name.buf, midx_hash, &ctx);
if (flags & MIDX_WRITE_BITMAP) {
struct packing_data pdata;
struct commit **commits;
uint32_t commits_nr;
if (!ctx.entries_nr)
BUG("cannot write a bitmap without any objects");
prepare_midx_packing_data(&pdata, &ctx);
commits = find_commits_for_midx_bitmap(&commits_nr, refs_snapshot, &ctx);
/*
* The previous steps translated the information from
* 'entries' into information suitable for constructing
* bitmaps. We no longer need that array, so clear it to
* reduce memory pressure.
*/
FREE_AND_NULL(ctx.entries);
ctx.entries_nr = 0;
if (write_midx_bitmap(midx_name.buf, midx_hash, &pdata,
commits, commits_nr, ctx.pack_order,
flags) < 0) {
error(_("could not write multi-pack bitmap"));
result = 1;
goto cleanup;
}
}
/*
* NOTE: Do not use ctx.entries beyond this point, since it might
* have been freed in the previous if block.
*/
if (ctx.m)
close_object_store(the_repository->objects);
if (commit_lock_file(&lk) < 0)
die_errno(_("could not write multi-pack-index"));
clear_midx_files_ext(object_dir, ".bitmap", midx_hash);
clear_midx_files_ext(object_dir, ".rev", midx_hash);
cleanup:
for (i = 0; i < ctx.nr; i++) {
if (ctx.info[i].p) {
close_pack(ctx.info[i].p);
free(ctx.info[i].p);
}
free(ctx.info[i].pack_name);
}
free(ctx.info);
free(ctx.entries);
free(ctx.pack_perm);
free(ctx.pack_order);
strbuf_release(&midx_name);
trace2_region_leave("midx", "write_midx_internal", the_repository);
return result;
}
int write_midx_file(const char *object_dir,
const char *preferred_pack_name,
const char *refs_snapshot,
unsigned flags)
{
return write_midx_internal(object_dir, NULL, NULL, preferred_pack_name,
refs_snapshot, flags);
}
int write_midx_file_only(const char *object_dir,
struct string_list *packs_to_include,
const char *preferred_pack_name,
const char *refs_snapshot,
unsigned flags)
{
return write_midx_internal(object_dir, packs_to_include, NULL,
preferred_pack_name, refs_snapshot, flags);
}
struct clear_midx_data {
char *keep;
const char *ext;
};
static void clear_midx_file_ext(const char *full_path, size_t full_path_len UNUSED,
const char *file_name, void *_data)
{
struct clear_midx_data *data = _data;
if (!(starts_with(file_name, "multi-pack-index-") &&
ends_with(file_name, data->ext)))
return;
if (data->keep && !strcmp(data->keep, file_name))
return;
if (unlink(full_path))
die_errno(_("failed to remove %s"), full_path);
}
static void clear_midx_files_ext(const char *object_dir, const char *ext,
unsigned char *keep_hash)
{
struct clear_midx_data data;
memset(&data, 0, sizeof(struct clear_midx_data));
if (keep_hash)
data.keep = xstrfmt("multi-pack-index-%s%s",
hash_to_hex(keep_hash), ext);
data.ext = ext;
for_each_file_in_pack_dir(object_dir,
clear_midx_file_ext,
&data);
free(data.keep);
}
void clear_midx_file(struct repository *r)
{
struct strbuf midx = STRBUF_INIT;
get_midx_filename(&midx, 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.buf))
die(_("failed to clear multi-pack-index at %s"), midx.buf);
clear_midx_files_ext(r->objects->odb->path, ".bitmap", NULL);
clear_midx_files_ext(r->objects->odb->path, ".rev", NULL);
strbuf_release(&midx);
}
static int verify_midx_error;
__attribute__((format (printf, 1, 2)))
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, unsigned flags)
{
struct pair_pos_vs_id *pairs = NULL;
uint32_t i;
struct progress *progress = NULL;
struct multi_pack_index *m = load_multi_pack_index(object_dir, 1);
verify_midx_error = 0;
if (!m) {
int result = 0;
struct stat sb;
struct strbuf filename = STRBUF_INIT;
get_midx_filename(&filename, object_dir);
if (!stat(filename.buf, &sb)) {
error(_("multi-pack-index file exists, but failed to parse"));
result = 1;
}
strbuf_release(&filename);
return result;
}
if (!midx_checksum_valid(m))
midx_report(_("incorrect checksum"));
if (flags & MIDX_PROGRESS)
progress = start_delayed_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);
}
if (m->num_objects == 0) {
midx_report(_("the midx contains no oid"));
/*
* Remaining tests assume that we have objects, so we can
* return here.
*/
goto cleanup;
}
if (flags & MIDX_PROGRESS)
progress = start_sparse_progress(_("Verifying OID order in multi-pack-index"),
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);
}
if (flags & MIDX_PROGRESS)
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);
if (flags & MIDX_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);
cleanup:
free(pairs);
close_midx(m);
return verify_midx_error;
}
int expire_midx_packs(struct repository *r, const char *object_dir, unsigned flags)
{
uint32_t i, *count, result = 0;
struct string_list packs_to_drop = STRING_LIST_INIT_DUP;
struct multi_pack_index *m = lookup_multi_pack_index(r, object_dir);
struct progress *progress = NULL;
if (!m)
return 0;
CALLOC_ARRAY(count, m->num_packs);
if (flags & MIDX_PROGRESS)
progress = start_delayed_progress(_("Counting referenced objects"),
m->num_objects);
for (i = 0; i < m->num_objects; i++) {
int pack_int_id = nth_midxed_pack_int_id(m, i);
count[pack_int_id]++;
display_progress(progress, i + 1);
}
stop_progress(&progress);
if (flags & MIDX_PROGRESS)
progress = start_delayed_progress(_("Finding and deleting unreferenced packfiles"),
m->num_packs);
for (i = 0; i < m->num_packs; i++) {
char *pack_name;
display_progress(progress, i + 1);
if (count[i])
continue;
if (prepare_midx_pack(r, m, i))
continue;
if (m->packs[i]->pack_keep || m->packs[i]->is_cruft)
continue;
pack_name = xstrdup(m->packs[i]->pack_name);
close_pack(m->packs[i]);
string_list_insert(&packs_to_drop, m->pack_names[i]);
unlink_pack_path(pack_name, 0);
free(pack_name);
}
stop_progress(&progress);
free(count);
if (packs_to_drop.nr)
result = write_midx_internal(object_dir, NULL, &packs_to_drop, NULL, NULL, flags);
string_list_clear(&packs_to_drop, 0);
return result;
}
struct repack_info {
timestamp_t mtime;
uint32_t referenced_objects;
uint32_t pack_int_id;
};
static int compare_by_mtime(const void *a_, const void *b_)
{
const struct repack_info *a, *b;
a = (const struct repack_info *)a_;
b = (const struct repack_info *)b_;
if (a->mtime < b->mtime)
return -1;
if (a->mtime > b->mtime)
return 1;
return 0;
}
static int fill_included_packs_all(struct repository *r,
struct multi_pack_index *m,
unsigned char *include_pack)
{
uint32_t i, count = 0;
int pack_kept_objects = 0;
repo_config_get_bool(r, "repack.packkeptobjects", &pack_kept_objects);
for (i = 0; i < m->num_packs; i++) {
if (prepare_midx_pack(r, m, i))
continue;
if (!pack_kept_objects && m->packs[i]->pack_keep)
continue;
if (m->packs[i]->is_cruft)
continue;
include_pack[i] = 1;
count++;
}
return count < 2;
}
static int fill_included_packs_batch(struct repository *r,
struct multi_pack_index *m,
unsigned char *include_pack,
size_t batch_size)
{
uint32_t i, packs_to_repack;
size_t total_size;
struct repack_info *pack_info;
int pack_kept_objects = 0;
CALLOC_ARRAY(pack_info, m->num_packs);
repo_config_get_bool(r, "repack.packkeptobjects", &pack_kept_objects);
for (i = 0; i < m->num_packs; i++) {
pack_info[i].pack_int_id = i;
if (prepare_midx_pack(r, m, i))
continue;
pack_info[i].mtime = m->packs[i]->mtime;
}
for (i = 0; i < m->num_objects; i++) {
uint32_t pack_int_id = nth_midxed_pack_int_id(m, i);
pack_info[pack_int_id].referenced_objects++;
}
QSORT(pack_info, m->num_packs, compare_by_mtime);
total_size = 0;
packs_to_repack = 0;
for (i = 0; total_size < batch_size && i < m->num_packs; i++) {
int pack_int_id = pack_info[i].pack_int_id;
struct packed_git *p = m->packs[pack_int_id];
size_t expected_size;
if (!p)
continue;
if (!pack_kept_objects && p->pack_keep)
continue;
if (p->is_cruft)
continue;
if (open_pack_index(p) || !p->num_objects)
continue;
expected_size = st_mult(p->pack_size,
pack_info[i].referenced_objects);
expected_size /= p->num_objects;
if (expected_size >= batch_size)
continue;
packs_to_repack++;
total_size += expected_size;
include_pack[pack_int_id] = 1;
}
free(pack_info);
if (packs_to_repack < 2)
return 1;
return 0;
}
int midx_repack(struct repository *r, const char *object_dir, size_t batch_size, unsigned flags)
{
int result = 0;
uint32_t i;
unsigned char *include_pack;
struct child_process cmd = CHILD_PROCESS_INIT;
FILE *cmd_in;
struct strbuf base_name = STRBUF_INIT;
struct multi_pack_index *m = lookup_multi_pack_index(r, object_dir);
/*
* When updating the default for these configuration
* variables in builtin/repack.c, these must be adjusted
* to match.
*/
int delta_base_offset = 1;
int use_delta_islands = 0;
if (!m)
return 0;
CALLOC_ARRAY(include_pack, m->num_packs);
if (batch_size) {
if (fill_included_packs_batch(r, m, include_pack, batch_size))
goto cleanup;
} else if (fill_included_packs_all(r, m, include_pack))
goto cleanup;
repo_config_get_bool(r, "repack.usedeltabaseoffset", &delta_base_offset);
repo_config_get_bool(r, "repack.usedeltaislands", &use_delta_islands);
strvec_push(&cmd.args, "pack-objects");
strbuf_addstr(&base_name, object_dir);
strbuf_addstr(&base_name, "/pack/pack");
strvec_push(&cmd.args, base_name.buf);
if (delta_base_offset)
strvec_push(&cmd.args, "--delta-base-offset");
if (use_delta_islands)
strvec_push(&cmd.args, "--delta-islands");
if (flags & MIDX_PROGRESS)
strvec_push(&cmd.args, "--progress");
else
strvec_push(&cmd.args, "-q");
strbuf_release(&base_name);
cmd.git_cmd = 1;
cmd.in = cmd.out = -1;
if (start_command(&cmd)) {
error(_("could not start pack-objects"));
result = 1;
goto cleanup;
}
cmd_in = xfdopen(cmd.in, "w");
for (i = 0; i < m->num_objects; i++) {
struct object_id oid;
uint32_t pack_int_id = nth_midxed_pack_int_id(m, i);
if (!include_pack[pack_int_id])
continue;
nth_midxed_object_oid(&oid, m, i);
fprintf(cmd_in, "%s\n", oid_to_hex(&oid));
}
fclose(cmd_in);
if (finish_command(&cmd)) {
error(_("could not finish pack-objects"));
result = 1;
goto cleanup;
}
result = write_midx_internal(object_dir, NULL, NULL, NULL, NULL, flags);
cleanup:
free(include_pack);
return result;
}