git/midx.c
Junio C Hamano 4488bb3bed Merge branch 'tb/object-access-overflow-protection'
Various offset computation in the code that accesses the packfiles
and other data in the object layer has been hardened against
arithmetic overflow, especially on 32-bit systems.

* tb/object-access-overflow-protection:
  commit-graph.c: prevent overflow in `verify_commit_graph()`
  commit-graph.c: prevent overflow in `write_commit_graph()`
  commit-graph.c: prevent overflow in `merge_commit_graph()`
  commit-graph.c: prevent overflow in `split_graph_merge_strategy()`
  commit-graph.c: prevent overflow in `load_tree_for_commit()`
  commit-graph.c: prevent overflow in `fill_commit_in_graph()`
  commit-graph.c: prevent overflow in `fill_commit_graph_info()`
  commit-graph.c: prevent overflow in `load_oid_from_graph()`
  commit-graph.c: prevent overflow in add_graph_to_chain()
  commit-graph.c: prevent overflow in `write_commit_graph_file()`
  pack-bitmap.c: ensure that eindex lookups don't overflow
  midx.c: prevent overflow in `fill_included_packs_batch()`
  midx.c: prevent overflow in `write_midx_internal()`
  midx.c: store `nr`, `alloc` variables as `size_t`'s
  midx.c: prevent overflow in `nth_midxed_offset()`
  midx.c: prevent overflow in `nth_midxed_object_oid()`
  midx.c: use `size_t`'s for fanout nr and alloc
  packfile.c: use checked arithmetic in `nth_packed_object_offset()`
  packfile.c: prevent overflow in `load_idx()`
  packfile.c: prevent overflow in `nth_packed_object_id()`
2023-07-25 12:05:23 -07:00

2101 lines
54 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;
}
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))
goto cleanup_fail;
if (pair_chunk(cf, MIDX_CHUNKID_PACKNAMES, &m->chunk_pack_names) == CHUNK_NOT_FOUND)
die(_("multi-pack-index missing required pack-name chunk"));
if (read_chunk(cf, MIDX_CHUNKID_OIDFANOUT, midx_read_oid_fanout, m) == CHUNK_NOT_FOUND)
die(_("multi-pack-index missing required OID fanout chunk"));
if (pair_chunk(cf, MIDX_CHUNKID_OIDLOOKUP, &m->chunk_oid_lookup) == CHUNK_NOT_FOUND)
die(_("multi-pack-index missing required OID lookup chunk"));
if (pair_chunk(cf, MIDX_CHUNKID_OBJECTOFFSETS, &m->chunk_object_offsets) == CHUNK_NOT_FOUND)
die(_("multi-pack-index missing required object offsets chunk"));
pair_chunk(cf, MIDX_CHUNKID_LARGEOFFSETS, &m->chunk_large_offsets);
if (git_env_bool("GIT_TEST_MIDX_READ_RIDX", 1))
pair_chunk(cf, MIDX_CHUNKID_REVINDEX, &m->chunk_revindex);
m->num_objects = ntohl(m->chunk_oid_fanout[255]);
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++) {
m->pack_names[i] = cur_pack_name;
cur_pack_name += strlen(cur_pack_name) + 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;
return get_be64(m->chunk_large_offsets +
st_mult(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;
}