/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include <zlib.h>
#include "git2/repository.h"
#include "git2/indexer.h"
#include "git2/sys/odb_backend.h"
#include "delta.h"
#include "futils.h"
#include "hash.h"
#include "midx.h"
#include "mwindow.h"
#include "odb.h"
#include "pack.h"
#include "git2/odb_backend.h"
/* re-freshen pack files no more than every 2 seconds */
#define FRESHEN_FREQUENCY 2
struct pack_backend {
git_odb_backend parent;
git_midx_file *midx;
git_vector midx_packs;
git_vector packs;
struct git_pack_file *last_found;
char *pack_folder;
};
struct pack_writepack {
struct git_odb_writepack parent;
git_indexer *indexer;
};
/**
* The wonderful tale of a Packed Object lookup query
* ===================================================
* A riveting and epic story of epicness and ASCII
* art, presented by yours truly,
* Sir Vicent of Marti
*
*
* Chapter 1: Once upon a time...
* Initialization of the Pack Backend
* --------------------------------------------------
*
* # git_odb_backend_pack
* | Creates the pack backend structure, initializes the
* | callback pointers to our default read() and exist() methods,
* | and tries to find the `pack` folder, if it exists. ODBs without a `pack`
* | folder are ignored altogether. If there is a `pack` folder, it tries to
* | preload all the known packfiles in the ODB.
* |
* |-# pack_backend__refresh
* | The `multi-pack-index` is loaded if it exists and is valid.
* | Then we run a `dirent` callback through every file in the pack folder,
* | even those present in `multi-pack-index`. The unindexed packfiles are
* | then sorted according to a sorting callback.
* |
* |-# refresh_multi_pack_index
* | Detect the presence of the `multi-pack-index` file. If it needs to be
* | refreshed, frees the old copy and tries to load the new one, together
* | with all the packfiles it indexes. If the process fails, fall back to
* | the old behavior, as if the `multi-pack-index` file was not there.
* |
* |-# packfile_load__cb
* | | This callback is called from `dirent` with every single file
* | | inside the pack folder. We find the packs by actually locating
* | | their index (ends in ".idx"). From that index, we verify that
* | | the corresponding packfile exists and is valid, and if so, we
* | | add it to the pack list.
* | |
* | # git_mwindow_get_pack
* | Make sure that there's a packfile to back this index, and store
* | some very basic information regarding the packfile itself,
* | such as the full path, the size, and the modification time.
* | We don't actually open the packfile to check for internal consistency.
* |
* |-# packfile_sort__cb
* Sort all the preloaded packs according to some specific criteria:
* we prioritize the "newer" packs because it's more likely they
* contain the objects we are looking for, and we prioritize local
* packs over remote ones.
*
*
*
* Chapter 2: To be, or not to be...
* A standard packed `exist` query for an OID
* --------------------------------------------------
*
* # pack_backend__exists / pack_backend__exists_prefix
* | Check if the given SHA1 oid (or a SHA1 oid prefix) exists in any of the
* | packs that have been loaded for our ODB.
* |
* |-# pack_entry_find / pack_entry_find_prefix
* | If there is a multi-pack-index present, search the SHA1 oid in that
* | index first. If it is not found there, iterate through all the unindexed
* | packs that have been preloaded (starting by the pack where the latest
* | object was found) to try to find the OID in one of them.
* |
* |-# git_midx_entry_find
* | Search for the SHA1 oid in the multi-pack-index. See
* | <https://github.com/git/git/blob/master/Documentation/technical/pack-format.txt>
* | for specifics on the multi-pack-index format and how do we find
* | entries in it.
* |
* |-# git_pack_entry_find
* | Check the index of an individual unindexed pack to see if the SHA1
* | OID can be found. If we can find the offset to that SHA1 inside of the
* | index, that means the object is contained inside of the packfile and
* | we can stop searching. Before returning, we verify that the
* | packfile behind the index we are searching still exists on disk.
* |
* |-# pack_entry_find_offset
* | Mmap the actual index file to disk if it hasn't been opened
* | yet, and run a binary search through it to find the OID.
* | See <https://github.com/git/git/blob/master/Documentation/technical/pack-format.txt>
* | for specifics on the Packfile Index format and how do we find
* | entries in it.
* |
* |-# pack_index_open
* | Guess the name of the index based on the full path to the
* | packfile, open it and verify its contents. Only if the index
* | has not been opened already.
* |
* |-# pack_index_check
* Mmap the index file and do a quick run through the header
* to guess the index version (right now we support v1 and v2),
* and to verify that the size of the index makes sense.
*
*
*
* Chapter 3: The neverending story...
* A standard packed `lookup` query for an OID
* --------------------------------------------------
*
* # pack_backend__read / pack_backend__read_prefix
* | Check if the given SHA1 oid (or a SHA1 oid prefix) exists in any of the
* | packs that have been loaded for our ODB. If it does, open the packfile and
* | read from it.
* |
* |-# git_packfile_unpack
* Armed with a packfile and the offset within it, we can finally unpack
* the object pointed at by the SHA1 oid. This involves mmapping part of
* the `.pack` file, and uncompressing the object within it (if it is
* stored in the undelfitied representation), or finding a base object and
* applying some deltas to its uncompressed representation (if it is stored
* in the deltified representation). See
* <https://github.com/git/git/blob/master/Documentation/technical/pack-format.txt>
* for specifics on the Packfile format and how do we read from it.
*
*/
/***********************************************************
*
* FORWARD DECLARATIONS
*
***********************************************************/
static int packfile_sort__cb(const void *a_, const void *b_);
static int packfile_load__cb(void *_data, git_str *path);
static int packfile_byname_search_cmp(const void *path, const void *pack_entry);
static int pack_entry_find(struct git_pack_entry *e,
struct pack_backend *backend, const git_oid *oid);
/* Can find the offset of an object given
* a prefix of an identifier.
* Sets GIT_EAMBIGUOUS if short oid is ambiguous.
* This method assumes that len is between
* GIT_OID_MINPREFIXLEN and GIT_OID_HEXSZ.
*/
static int pack_entry_find_prefix(
struct git_pack_entry *e,
struct pack_backend *backend,
const git_oid *short_oid,
size_t len);
/***********************************************************
*
* PACK WINDOW MANAGEMENT
*
***********************************************************/
static int packfile_byname_search_cmp(const void *path_, const void *p_)
{
const git_str *path = (const git_str *)path_;
const struct git_pack_file *p = (const struct git_pack_file *)p_;
return strncmp(p->pack_name, git_str_cstr(path), git_str_len(path));
}
static int packfile_sort__cb(const void *a_, const void *b_)
{
const struct git_pack_file *a = a_;
const struct git_pack_file *b = b_;
int st;
/*
* Local packs tend to contain objects specific to our
* variant of the project than remote ones. In addition,
* remote ones could be on a network mounted filesystem.
* Favor local ones for these reasons.
*/
st = a->pack_local - b->pack_local;
if (st)
return -st;
/*
* Younger packs tend to contain more recent objects,
* and more recent objects tend to get accessed more
* often.
*/
if (a->mtime < b->mtime)
return 1;
else if (a->mtime == b->mtime)
return 0;
return -1;
}
static int packfile_load__cb(void *data, git_str *path)
{
struct pack_backend *backend = data;
struct git_pack_file *pack;
const char *path_str = git_str_cstr(path);
git_str index_prefix = GIT_STR_INIT;
size_t cmp_len = git_str_len(path);
int error;
if (cmp_len <= strlen(".idx") || git__suffixcmp(path_str, ".idx") != 0)
return 0; /* not an index */
cmp_len -= strlen(".idx");
git_str_attach_notowned(&index_prefix, path_str, cmp_len);
if (git_vector_search2(NULL, &backend->midx_packs, packfile_byname_search_cmp, &index_prefix) == 0)
return 0;
if (git_vector_search2(NULL, &backend->packs, packfile_byname_search_cmp, &index_prefix) == 0)
return 0;
error = git_mwindow_get_pack(&pack, path->ptr);
/* ignore missing .pack file as git does */
if (error == GIT_ENOTFOUND) {
git_error_clear();
return 0;
}
if (!error)
error = git_vector_insert(&backend->packs, pack);
return error;
}
static int pack_entry_find(struct git_pack_entry *e, struct pack_backend *backend, const git_oid *oid)
{
struct git_pack_file *last_found = backend->last_found, *p;
git_midx_entry midx_entry;
size_t i;
if (backend->midx &&
git_midx_entry_find(&midx_entry, backend->midx, oid, GIT_OID_HEXSZ) == 0 &&
midx_entry.pack_index < git_vector_length(&backend->midx_packs)) {
e->offset = midx_entry.offset;
git_oid_cpy(&e->sha1, &midx_entry.sha1);
e->p = git_vector_get(&backend->midx_packs, midx_entry.pack_index);
return 0;
}
if (last_found &&
git_pack_entry_find(e, last_found, oid, GIT_OID_HEXSZ) == 0)
return 0;
git_vector_foreach(&backend->packs, i, p) {
if (p == last_found)
continue;
if (git_pack_entry_find(e, p, oid, GIT_OID_HEXSZ) == 0) {
backend->last_found = p;
return 0;
}
}
return git_odb__error_notfound(
"failed to find pack entry", oid, GIT_OID_HEXSZ);
}
static int pack_entry_find_prefix(
struct git_pack_entry *e,
struct pack_backend *backend,
const git_oid *short_oid,
size_t len)
{
int error;
size_t i;
git_oid found_full_oid = {{0}};
bool found = false;
struct git_pack_file *last_found = backend->last_found, *p;
git_midx_entry midx_entry;
if (backend->midx) {
error = git_midx_entry_find(&midx_entry, backend->midx, short_oid, len);
if (error == GIT_EAMBIGUOUS)
return error;
if (!error && midx_entry.pack_index < git_vector_length(&backend->midx_packs)) {
e->offset = midx_entry.offset;
git_oid_cpy(&e->sha1, &midx_entry.sha1);
e->p = git_vector_get(&backend->midx_packs, midx_entry.pack_index);
git_oid_cpy(&found_full_oid, &e->sha1);
found = true;
}
}
if (last_found) {
error = git_pack_entry_find(e, last_found, short_oid, len);
if (error == GIT_EAMBIGUOUS)
return error;
if (!error) {
if (found && git_oid_cmp(&e->sha1, &found_full_oid))
return git_odb__error_ambiguous("found multiple pack entries");
git_oid_cpy(&found_full_oid, &e->sha1);
found = true;
}
}
git_vector_foreach(&backend->packs, i, p) {
if (p == last_found)
continue;
error = git_pack_entry_find(e, p, short_oid, len);
if (error == GIT_EAMBIGUOUS)
return error;
if (!error) {
if (found && git_oid_cmp(&e->sha1, &found_full_oid))
return git_odb__error_ambiguous("found multiple pack entries");
git_oid_cpy(&found_full_oid, &e->sha1);
found = true;
backend->last_found = p;
}
}
if (!found)
return git_odb__error_notfound("no matching pack entry for prefix",
short_oid, len);
else
return 0;
}
/***********************************************************
*
* MULTI-PACK-INDEX SUPPORT
*
* Functions needed to support the multi-pack-index.
*
***********************************************************/
/*
* Remove the multi-pack-index, and move all midx_packs to packs.
*/
static int remove_multi_pack_index(struct pack_backend *backend)
{
size_t i, j = git_vector_length(&backend->packs);
struct pack_backend *p;
int error = git_vector_size_hint(
&backend->packs,
j + git_vector_length(&backend->midx_packs));
if (error < 0)
return error;
git_vector_foreach(&backend->midx_packs, i, p)
git_vector_set(NULL, &backend->packs, j++, p);
git_vector_clear(&backend->midx_packs);
git_midx_free(backend->midx);
backend->midx = NULL;
return 0;
}
/*
* Loads a single .pack file referred to by the multi-pack-index. These must
* match the order in which they are declared in the multi-pack-index file,
* since these files are referred to by their index.
*/
static int process_multi_pack_index_pack(
struct pack_backend *backend,
size_t i,
const char *packfile_name)
{
int error;
struct git_pack_file *pack;
size_t found_position;
git_str pack_path = GIT_STR_INIT, index_prefix = GIT_STR_INIT;
error = git_str_joinpath(&pack_path, backend->pack_folder, packfile_name);
if (error < 0)
return error;
/* This is ensured by midx_parse_packfile_name() */
if (git_str_len(&pack_path) <= strlen(".idx") || git__suffixcmp(git_str_cstr(&pack_path), ".idx") != 0)
return git_odb__error_notfound("midx file contained a non-index", NULL, 0);
git_str_attach_notowned(&index_prefix, git_str_cstr(&pack_path), git_str_len(&pack_path) - strlen(".idx"));
if (git_vector_search2(&found_position, &backend->packs, packfile_byname_search_cmp, &index_prefix) == 0) {
/* Pack was found in the packs list. Moving it to the midx_packs list. */
git_str_dispose(&pack_path);
git_vector_set(NULL, &backend->midx_packs, i, git_vector_get(&backend->packs, found_position));
git_vector_remove(&backend->packs, found_position);
return 0;
}
/* Pack was not found. Allocate a new one. */
error = git_mwindow_get_pack(&pack, git_str_cstr(&pack_path));
git_str_dispose(&pack_path);
if (error < 0)
return error;
git_vector_set(NULL, &backend->midx_packs, i, pack);
return 0;
}
/*
* Reads the multi-pack-index. If this fails for whatever reason, the
* multi-pack-index object is freed, and all the packfiles that are related to
* it are moved to the unindexed packfiles vector.
*/
static int refresh_multi_pack_index(struct pack_backend *backend)
{
int error;
git_str midx_path = GIT_STR_INIT;
const char *packfile_name;
size_t i;
error = git_str_joinpath(&midx_path, backend->pack_folder, "multi-pack-index");
if (error < 0)
return error;
/*
* Check whether the multi-pack-index has changed. If it has, close any
* old multi-pack-index and move all the packfiles to the unindexed
* packs. This is done to prevent losing any open packfiles in case
* refreshing the new multi-pack-index fails, or the file is deleted.
*/
if (backend->midx) {
if (!git_midx_needs_refresh(backend->midx, git_str_cstr(&midx_path))) {
git_str_dispose(&midx_path);
return 0;
}
error = remove_multi_pack_index(backend);
if (error < 0) {
git_str_dispose(&midx_path);
return error;
}
}
error = git_midx_open(&backend->midx, git_str_cstr(&midx_path));
git_str_dispose(&midx_path);
if (error < 0)
return error;
git_vector_resize_to(&backend->midx_packs, git_vector_length(&backend->midx->packfile_names));
git_vector_foreach(&backend->midx->packfile_names, i, packfile_name) {
error = process_multi_pack_index_pack(backend, i, packfile_name);
if (error < 0) {
/*
* Something failed during reading multi-pack-index.
* Restore the state of backend as if the
* multi-pack-index was never there, and move all
* packfiles that have been processed so far to the
* unindexed packs.
*/
git_vector_resize_to(&backend->midx_packs, i);
remove_multi_pack_index(backend);
return error;
}
}
return 0;
}
/***********************************************************
*
* PACKED BACKEND PUBLIC API
*
* Implement the git_odb_backend API calls
*
***********************************************************/
static int pack_backend__refresh(git_odb_backend *backend_)
{
int error;
struct stat st;
git_str path = GIT_STR_INIT;
struct pack_backend *backend = (struct pack_backend *)backend_;
if (backend->pack_folder == NULL)
return 0;
if (p_stat(backend->pack_folder, &st) < 0 || !S_ISDIR(st.st_mode))
return git_odb__error_notfound("failed to refresh packfiles", NULL, 0);
if (refresh_multi_pack_index(backend) < 0) {
/*
* It is okay if this fails. We will just not use the
* multi-pack-index in this case.
*/
git_error_clear();
}
/* reload all packs */
git_str_sets(&path, backend->pack_folder);
error = git_fs_path_direach(&path, 0, packfile_load__cb, backend);
git_str_dispose(&path);
git_vector_sort(&backend->packs);
return error;
}
static int pack_backend__read_header(
size_t *len_p, git_object_t *type_p,
struct git_odb_backend *backend, const git_oid *oid)
{
struct git_pack_entry e;
int error;
GIT_ASSERT_ARG(len_p);
GIT_ASSERT_ARG(type_p);
GIT_ASSERT_ARG(backend);
GIT_ASSERT_ARG(oid);
if ((error = pack_entry_find(&e, (struct pack_backend *)backend, oid)) < 0)
return error;
return git_packfile_resolve_header(len_p, type_p, e.p, e.offset);
}
static int pack_backend__freshen(
git_odb_backend *backend, const git_oid *oid)
{
struct git_pack_entry e;
time_t now;
int error;
if ((error = pack_entry_find(&e, (struct pack_backend *)backend, oid)) < 0)
return error;
now = time(NULL);
if (e.p->last_freshen > now - FRESHEN_FREQUENCY)
return 0;
if ((error = git_futils_touch(e.p->pack_name, &now)) < 0)
return error;
e.p->last_freshen = now;
return 0;
}
static int pack_backend__read(
void **buffer_p, size_t *len_p, git_object_t *type_p,
git_odb_backend *backend, const git_oid *oid)
{
struct git_pack_entry e;
git_rawobj raw = {NULL};
int error;
if ((error = pack_entry_find(&e, (struct pack_backend *)backend, oid)) < 0 ||
(error = git_packfile_unpack(&raw, e.p, &e.offset)) < 0)
return error;
*buffer_p = raw.data;
*len_p = raw.len;
*type_p = raw.type;
return 0;
}
static int pack_backend__read_prefix(
git_oid *out_oid,
void **buffer_p,
size_t *len_p,
git_object_t *type_p,
git_odb_backend *backend,
const git_oid *short_oid,
size_t len)
{
int error = 0;
if (len < GIT_OID_MINPREFIXLEN)
error = git_odb__error_ambiguous("prefix length too short");
else if (len >= GIT_OID_HEXSZ) {
/* We can fall back to regular read method */
error = pack_backend__read(buffer_p, len_p, type_p, backend, short_oid);
if (!error)
git_oid_cpy(out_oid, short_oid);
} else {
struct git_pack_entry e;
git_rawobj raw = {NULL};
if ((error = pack_entry_find_prefix(
&e, (struct pack_backend *)backend, short_oid, len)) == 0 &&
(error = git_packfile_unpack(&raw, e.p, &e.offset)) == 0)
{
*buffer_p = raw.data;
*len_p = raw.len;
*type_p = raw.type;
git_oid_cpy(out_oid, &e.sha1);
}
}
return error;
}
static int pack_backend__exists(git_odb_backend *backend, const git_oid *oid)
{
struct git_pack_entry e;
return pack_entry_find(&e, (struct pack_backend *)backend, oid) == 0;
}
static int pack_backend__exists_prefix(
git_oid *out, git_odb_backend *backend, const git_oid *short_id, size_t len)
{
int error;
struct pack_backend *pb = (struct pack_backend *)backend;
struct git_pack_entry e = {0};
error = pack_entry_find_prefix(&e, pb, short_id, len);
git_oid_cpy(out, &e.sha1);
return error;
}
static int pack_backend__foreach(git_odb_backend *_backend, git_odb_foreach_cb cb, void *data)
{
int error;
struct git_pack_file *p;
struct pack_backend *backend;
unsigned int i;
GIT_ASSERT_ARG(_backend);
GIT_ASSERT_ARG(cb);
backend = (struct pack_backend *)_backend;
/* Make sure we know about the packfiles */
if ((error = pack_backend__refresh(_backend)) != 0)
return error;
if (backend->midx && (error = git_midx_foreach_entry(backend->midx, cb, data)) != 0)
return error;
git_vector_foreach(&backend->packs, i, p) {
if ((error = git_pack_foreach_entry(p, cb, data)) != 0)
return error;
}
return 0;
}
static int pack_backend__writepack_append(struct git_odb_writepack *_writepack, const void *data, size_t size, git_indexer_progress *stats)
{
struct pack_writepack *writepack = (struct pack_writepack *)_writepack;
GIT_ASSERT_ARG(writepack);
return git_indexer_append(writepack->indexer, data, size, stats);
}
static int pack_backend__writepack_commit(struct git_odb_writepack *_writepack, git_indexer_progress *stats)
{
struct pack_writepack *writepack = (struct pack_writepack *)_writepack;
GIT_ASSERT_ARG(writepack);
return git_indexer_commit(writepack->indexer, stats);
}
static void pack_backend__writepack_free(struct git_odb_writepack *_writepack)
{
struct pack_writepack *writepack;
if (!_writepack)
return;
writepack = (struct pack_writepack *)_writepack;
git_indexer_free(writepack->indexer);
git__free(writepack);
}
static int pack_backend__writepack(struct git_odb_writepack **out,
git_odb_backend *_backend,
git_odb *odb,
git_indexer_progress_cb progress_cb,
void *progress_payload)
{
git_indexer_options opts = GIT_INDEXER_OPTIONS_INIT;
struct pack_backend *backend;
struct pack_writepack *writepack;
GIT_ASSERT_ARG(out);
GIT_ASSERT_ARG(_backend);
*out = NULL;
opts.progress_cb = progress_cb;
opts.progress_cb_payload = progress_payload;
backend = (struct pack_backend *)_backend;
writepack = git__calloc(1, sizeof(struct pack_writepack));
GIT_ERROR_CHECK_ALLOC(writepack);
if (git_indexer_new(&writepack->indexer,
backend->pack_folder, 0, odb, &opts) < 0) {
git__free(writepack);
return -1;
}
writepack->parent.backend = _backend;
writepack->parent.append = pack_backend__writepack_append;
writepack->parent.commit = pack_backend__writepack_commit;
writepack->parent.free = pack_backend__writepack_free;
*out = (git_odb_writepack *)writepack;
return 0;
}
static int get_idx_path(
git_str *idx_path,
struct pack_backend *backend,
struct git_pack_file *p)
{
size_t path_len;
int error;
error = git_fs_path_prettify(idx_path, p->pack_name, backend->pack_folder);
if (error < 0)
return error;
path_len = git_str_len(idx_path);
if (path_len <= strlen(".pack") || git__suffixcmp(git_str_cstr(idx_path), ".pack") != 0)
return git_odb__error_notfound("packfile does not end in .pack", NULL, 0);
path_len -= strlen(".pack");
error = git_str_splice(idx_path, path_len, strlen(".pack"), ".idx", strlen(".idx"));
if (error < 0)
return error;
return 0;
}
static int pack_backend__writemidx(git_odb_backend *_backend)
{
struct pack_backend *backend;
git_midx_writer *w = NULL;
struct git_pack_file *p;
size_t i;
int error = 0;
GIT_ASSERT_ARG(_backend);
backend = (struct pack_backend *)_backend;
error = git_midx_writer_new(&w, backend->pack_folder);
if (error < 0)
return error;
git_vector_foreach(&backend->midx_packs, i, p) {
git_str idx_path = GIT_STR_INIT;
error = get_idx_path(&idx_path, backend, p);
if (error < 0)
goto cleanup;
error = git_midx_writer_add(w, git_str_cstr(&idx_path));
git_str_dispose(&idx_path);
if (error < 0)
goto cleanup;
}
git_vector_foreach(&backend->packs, i, p) {
git_str idx_path = GIT_STR_INIT;
error = get_idx_path(&idx_path, backend, p);
if (error < 0)
goto cleanup;
error = git_midx_writer_add(w, git_str_cstr(&idx_path));
git_str_dispose(&idx_path);
if (error < 0)
goto cleanup;
}
/*
* Invalidate the previous midx before writing the new one.
*/
error = remove_multi_pack_index(backend);
if (error < 0)
goto cleanup;
error = git_midx_writer_commit(w);
if (error < 0)
goto cleanup;
error = refresh_multi_pack_index(backend);
cleanup:
git_midx_writer_free(w);
return error;
}
static void pack_backend__free(git_odb_backend *_backend)
{
struct pack_backend *backend;
struct git_pack_file *p;
size_t i;
if (!_backend)
return;
backend = (struct pack_backend *)_backend;
git_vector_foreach(&backend->midx_packs, i, p)
git_mwindow_put_pack(p);
git_vector_foreach(&backend->packs, i, p)
git_mwindow_put_pack(p);
git_midx_free(backend->midx);
git_vector_free(&backend->midx_packs);
git_vector_free(&backend->packs);
git__free(backend->pack_folder);
git__free(backend);
}
static int pack_backend__alloc(struct pack_backend **out, size_t initial_size)
{
struct pack_backend *backend = git__calloc(1, sizeof(struct pack_backend));
GIT_ERROR_CHECK_ALLOC(backend);
if (git_vector_init(&backend->midx_packs, 0, NULL) < 0) {
git__free(backend);
return -1;
}
if (git_vector_init(&backend->packs, initial_size, packfile_sort__cb) < 0) {
git_vector_free(&backend->midx_packs);
git__free(backend);
return -1;
}
backend->parent.version = GIT_ODB_BACKEND_VERSION;
backend->parent.read = &pack_backend__read;
backend->parent.read_prefix = &pack_backend__read_prefix;
backend->parent.read_header = &pack_backend__read_header;
backend->parent.exists = &pack_backend__exists;
backend->parent.exists_prefix = &pack_backend__exists_prefix;
backend->parent.refresh = &pack_backend__refresh;
backend->parent.foreach = &pack_backend__foreach;
backend->parent.writepack = &pack_backend__writepack;
backend->parent.writemidx = &pack_backend__writemidx;
backend->parent.freshen = &pack_backend__freshen;
backend->parent.free = &pack_backend__free;
*out = backend;
return 0;
}
int git_odb_backend_one_pack(git_odb_backend **backend_out, const char *idx)
{
struct pack_backend *backend = NULL;
struct git_pack_file *packfile = NULL;
if (pack_backend__alloc(&backend, 1) < 0)
return -1;
if (git_mwindow_get_pack(&packfile, idx) < 0 ||
git_vector_insert(&backend->packs, packfile) < 0)
{
pack_backend__free((git_odb_backend *)backend);
return -1;
}
*backend_out = (git_odb_backend *)backend;
return 0;
}
int git_odb_backend_pack(git_odb_backend **backend_out, const char *objects_dir)
{
int error = 0;
struct pack_backend *backend = NULL;
git_str path = GIT_STR_INIT;
if (pack_backend__alloc(&backend, 8) < 0)
return -1;
if (!(error = git_str_joinpath(&path, objects_dir, "pack")) &&
git_fs_path_isdir(git_str_cstr(&path)))
{
backend->pack_folder = git_str_detach(&path);
error = pack_backend__refresh((git_odb_backend *)backend);
}
if (error < 0) {
pack_backend__free((git_odb_backend *)backend);
backend = NULL;
}
*backend_out = (git_odb_backend *)backend;
git_str_dispose(&path);
return error;
}
