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refdb_fs.c
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/*
* 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 "refs.h"
#include "hash.h"
#include "repository.h"
#include "fileops.h"
#include "filebuf.h"
#include "pack.h"
#include "reflog.h"
#include "refdb.h"
#include "refdb_fs.h"
#include "iterator.h"
#include "sortedcache.h"
#include "signature.h"
#include <git2/tag.h>
#include <git2/object.h>
#include <git2/refdb.h>
#include <git2/branch.h>
#include <git2/sys/refdb_backend.h>
#include <git2/sys/refs.h>
#include <git2/sys/reflog.h>
#define DEFAULT_NESTING_LEVEL 5
#define MAX_NESTING_LEVEL 10
enum {
PACKREF_HAS_PEEL = 1,
PACKREF_WAS_LOOSE = 2,
PACKREF_CANNOT_PEEL = 4,
PACKREF_SHADOWED = 8,
};
enum {
PEELING_NONE = 0,
PEELING_STANDARD,
PEELING_FULL
};
struct packref {
git_oid oid;
git_oid peel;
char flags;
char name[GIT_FLEX_ARRAY];
};
typedef struct refdb_fs_backend {
git_refdb_backend parent;
git_repository *repo;
/* path to git directory */
char *gitpath;
/* path to common objects' directory */
char *commonpath;
git_sortedcache *refcache;
int peeling_mode;
git_iterator_flag_t iterator_flags;
uint32_t direach_flags;
int fsync;
} refdb_fs_backend;
static int refdb_reflog_fs__delete(git_refdb_backend *_backend, const char *name);
static int packref_cmp(const void *a_, const void *b_)
{
const struct packref *a = a_, *b = b_;
return strcmp(a->name, b->name);
}
static int packed_reload(refdb_fs_backend *backend)
{
int error;
git_buf packedrefs = GIT_BUF_INIT;
char *scan, *eof, *eol;
if (!backend->gitpath)
return 0;
error = git_sortedcache_lockandload(backend->refcache, &packedrefs);
/*
* If we can't find the packed-refs, clear table and return.
* Any other error just gets passed through.
* If no error, and file wasn't changed, just return.
* Anything else means we need to refresh the packed refs.
*/
if (error <= 0) {
if (error == GIT_ENOTFOUND) {
git_sortedcache_clear(backend->refcache, true);
giterr_clear();
error = 0;
}
return error;
}
/* At this point, refresh the packed refs from the loaded buffer. */
git_sortedcache_clear(backend->refcache, false);
scan = (char *)packedrefs.ptr;
eof = scan + packedrefs.size;
backend->peeling_mode = PEELING_NONE;
if (*scan == '#') {
static const char *traits_header = "# pack-refs with: ";
if (git__prefixcmp(scan, traits_header) == 0) {
scan += strlen(traits_header);
eol = strchr(scan, '\n');
if (!eol)
goto parse_failed;
*eol = '\0';
if (strstr(scan, " fully-peeled ") != NULL) {
backend->peeling_mode = PEELING_FULL;
} else if (strstr(scan, " peeled ") != NULL) {
backend->peeling_mode = PEELING_STANDARD;
}
scan = eol + 1;
}
}
while (scan < eof && *scan == '#') {
if (!(eol = strchr(scan, '\n')))
goto parse_failed;
scan = eol + 1;
}
while (scan < eof) {
struct packref *ref;
git_oid oid;
/* parse "<OID> <refname>\n" */
if (git_oid_fromstr(&oid, scan) < 0)
goto parse_failed;
scan += GIT_OID_HEXSZ;
if (*scan++ != ' ')
goto parse_failed;
if (!(eol = strchr(scan, '\n')))
goto parse_failed;
*eol = '\0';
if (eol[-1] == '\r')
eol[-1] = '\0';
if (git_sortedcache_upsert((void **)&ref, backend->refcache, scan) < 0)
goto parse_failed;
scan = eol + 1;
git_oid_cpy(&ref->oid, &oid);
/* look for optional "^<OID>\n" */
if (*scan == '^') {
if (git_oid_fromstr(&oid, scan + 1) < 0)
goto parse_failed;
scan += GIT_OID_HEXSZ + 1;
if (scan < eof) {
if (!(eol = strchr(scan, '\n')))
goto parse_failed;
scan = eol + 1;
}
git_oid_cpy(&ref->peel, &oid);
ref->flags |= PACKREF_HAS_PEEL;
}
else if (backend->peeling_mode == PEELING_FULL ||
(backend->peeling_mode == PEELING_STANDARD &&
git__prefixcmp(ref->name, GIT_REFS_TAGS_DIR) == 0))
ref->flags |= PACKREF_CANNOT_PEEL;
}
git_sortedcache_wunlock(backend->refcache);
git_buf_free(&packedrefs);
return 0;
parse_failed:
giterr_set(GITERR_REFERENCE, "corrupted packed references file");
git_sortedcache_clear(backend->refcache, false);
git_sortedcache_wunlock(backend->refcache);
git_buf_free(&packedrefs);
return -1;
}
static int loose_parse_oid(
git_oid *oid, const char *filename, git_buf *file_content)
{
const char *str = git_buf_cstr(file_content);
if (git_buf_len(file_content) < GIT_OID_HEXSZ)
goto corrupted;
/* we need to get 40 OID characters from the file */
if (git_oid_fromstr(oid, str) < 0)
goto corrupted;
/* If the file is longer than 40 chars, the 41st must be a space */
str += GIT_OID_HEXSZ;
if (*str == '\0' || git__isspace(*str))
return 0;
corrupted:
giterr_set(GITERR_REFERENCE, "corrupted loose reference file: %s", filename);
return -1;
}
static int loose_readbuffer(git_buf *buf, const char *base, const char *path)
{
int error;
/* build full path to file */
if ((error = git_buf_joinpath(buf, base, path)) < 0 ||
(error = git_futils_readbuffer(buf, buf->ptr)) < 0)
git_buf_free(buf);
return error;
}
static int loose_lookup_to_packfile(refdb_fs_backend *backend, const char *name)
{
int error = 0;
git_buf ref_file = GIT_BUF_INIT;
struct packref *ref = NULL;
git_oid oid;
/* if we fail to load the loose reference, assume someone changed
* the filesystem under us and skip it...
*/
if (loose_readbuffer(&ref_file, backend->gitpath, name) < 0) {
giterr_clear();
goto done;
}
/* skip symbolic refs */
if (!git__prefixcmp(git_buf_cstr(&ref_file), GIT_SYMREF))
goto done;
/* parse OID from file */
if ((error = loose_parse_oid(&oid, name, &ref_file)) < 0)
goto done;
git_sortedcache_wlock(backend->refcache);
if (!(error = git_sortedcache_upsert(
(void **)&ref, backend->refcache, name))) {
git_oid_cpy(&ref->oid, &oid);
ref->flags = PACKREF_WAS_LOOSE;
}
git_sortedcache_wunlock(backend->refcache);
done:
git_buf_free(&ref_file);
return error;
}
static int _dirent_loose_load(void *payload, git_buf *full_path)
{
refdb_fs_backend *backend = payload;
const char *file_path;
if (git__suffixcmp(full_path->ptr, ".lock") == 0)
return 0;
if (git_path_isdir(full_path->ptr)) {
int error = git_path_direach(
full_path, backend->direach_flags, _dirent_loose_load, backend);
/* Race with the filesystem, ignore it */
if (error == GIT_ENOTFOUND) {
giterr_clear();
return 0;
}
return error;
}
file_path = full_path->ptr + strlen(backend->gitpath);
return loose_lookup_to_packfile(backend, file_path);
}
/*
* Load all the loose references from the repository
* into the in-memory Packfile, and build a vector with
* all the references so it can be written back to
* disk.
*/
static int packed_loadloose(refdb_fs_backend *backend)
{
int error;
git_buf refs_path = GIT_BUF_INIT;
if (git_buf_joinpath(&refs_path, backend->gitpath, GIT_REFS_DIR) < 0)
return -1;
/*
* Load all the loose files from disk into the Packfile table.
* This will overwrite any old packed entries with their
* updated loose versions
*/
error = git_path_direach(
&refs_path, backend->direach_flags, _dirent_loose_load, backend);
git_buf_free(&refs_path);
return error;
}
static int refdb_fs_backend__exists(
int *exists,
git_refdb_backend *_backend,
const char *ref_name)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
git_buf ref_path = GIT_BUF_INIT;
int error;
assert(backend);
if ((error = packed_reload(backend)) < 0 ||
(error = git_buf_joinpath(&ref_path, backend->gitpath, ref_name)) < 0)
return error;
*exists = git_path_isfile(ref_path.ptr) ||
(git_sortedcache_lookup(backend->refcache, ref_name) != NULL);
git_buf_free(&ref_path);
return 0;
}
static const char *loose_parse_symbolic(git_buf *file_content)
{
const unsigned int header_len = (unsigned int)strlen(GIT_SYMREF);
const char *refname_start;
refname_start = (const char *)file_content->ptr;
if (git_buf_len(file_content) < header_len + 1) {
giterr_set(GITERR_REFERENCE, "corrupted loose reference file");
return NULL;
}
/*
* Assume we have already checked for the header
* before calling this function
*/
refname_start += header_len;
return refname_start;
}
/*
* Returns whether a reference is stored per worktree or not.
* Per-worktree references are:
*
* - all pseudorefs, e.g. HEAD and MERGE_HEAD
* - all references stored inside of "refs/bisect/"
*/
static bool is_per_worktree_ref(const char *ref_name)
{
return git__prefixcmp(ref_name, "refs/") != 0 ||
git__prefixcmp(ref_name, "refs/bisect/") == 0;
}
static int loose_lookup(
git_reference **out,
refdb_fs_backend *backend,
const char *ref_name)
{
git_buf ref_file = GIT_BUF_INIT;
int error = 0;
const char *ref_dir;
if (out)
*out = NULL;
if (is_per_worktree_ref(ref_name))
ref_dir = backend->gitpath;
else
ref_dir = backend->commonpath;
if ((error = loose_readbuffer(&ref_file, ref_dir, ref_name)) < 0)
/* cannot read loose ref file - gah */;
else if (git__prefixcmp(git_buf_cstr(&ref_file), GIT_SYMREF) == 0) {
const char *target;
git_buf_rtrim(&ref_file);
if (!(target = loose_parse_symbolic(&ref_file)))
error = -1;
else if (out != NULL)
*out = git_reference__alloc_symbolic(ref_name, target);
} else {
git_oid oid;
if (!(error = loose_parse_oid(&oid, ref_name, &ref_file)) &&
out != NULL)
*out = git_reference__alloc(ref_name, &oid, NULL);
}
git_buf_free(&ref_file);
return error;
}
static int ref_error_notfound(const char *name)
{
giterr_set(GITERR_REFERENCE, "reference '%s' not found", name);
return GIT_ENOTFOUND;
}
static int packed_lookup(
git_reference **out,
refdb_fs_backend *backend,
const char *ref_name)
{
int error = 0;
struct packref *entry;
if ((error = packed_reload(backend)) < 0)
return error;
if (git_sortedcache_rlock(backend->refcache) < 0)
return -1;
entry = git_sortedcache_lookup(backend->refcache, ref_name);
if (!entry) {
error = ref_error_notfound(ref_name);
} else {
*out = git_reference__alloc(ref_name, &entry->oid, &entry->peel);
if (!*out)
error = -1;
}
git_sortedcache_runlock(backend->refcache);
return error;
}
static int refdb_fs_backend__lookup(
git_reference **out,
git_refdb_backend *_backend,
const char *ref_name)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
int error;
assert(backend);
if (!(error = loose_lookup(out, backend, ref_name)))
return 0;
/* only try to lookup this reference on the packfile if it
* wasn't found on the loose refs; not if there was a critical error */
if (error == GIT_ENOTFOUND) {
giterr_clear();
error = packed_lookup(out, backend, ref_name);
}
return error;
}
typedef struct {
git_reference_iterator parent;
char *glob;
git_pool pool;
git_vector loose;
git_sortedcache *cache;
size_t loose_pos;
size_t packed_pos;
} refdb_fs_iter;
static void refdb_fs_backend__iterator_free(git_reference_iterator *_iter)
{
refdb_fs_iter *iter = (refdb_fs_iter *) _iter;
git_vector_free(&iter->loose);
git_pool_clear(&iter->pool);
git_sortedcache_free(iter->cache);
git__free(iter);
}
static int iter_load_loose_paths(refdb_fs_backend *backend, refdb_fs_iter *iter)
{
int error = 0;
git_buf path = GIT_BUF_INIT;
git_iterator *fsit = NULL;
git_iterator_options fsit_opts = GIT_ITERATOR_OPTIONS_INIT;
const git_index_entry *entry = NULL;
if (!backend->commonpath) /* do nothing if no commonpath for loose refs */
return 0;
fsit_opts.flags = backend->iterator_flags;
if ((error = git_buf_printf(&path, "%s/refs", backend->commonpath)) < 0 ||
(error = git_iterator_for_filesystem(&fsit, path.ptr, &fsit_opts)) < 0) {
git_buf_free(&path);
return error;
}
error = git_buf_sets(&path, GIT_REFS_DIR);
while (!error && !git_iterator_advance(&entry, fsit)) {
const char *ref_name;
struct packref *ref;
char *ref_dup;
git_buf_truncate(&path, strlen(GIT_REFS_DIR));
git_buf_puts(&path, entry->path);
ref_name = git_buf_cstr(&path);
if (git__suffixcmp(ref_name, ".lock") == 0 ||
(iter->glob && p_fnmatch(iter->glob, ref_name, 0) != 0))
continue;
git_sortedcache_rlock(backend->refcache);
ref = git_sortedcache_lookup(backend->refcache, ref_name);
if (ref)
ref->flags |= PACKREF_SHADOWED;
git_sortedcache_runlock(backend->refcache);
ref_dup = git_pool_strdup(&iter->pool, ref_name);
if (!ref_dup)
error = -1;
else
error = git_vector_insert(&iter->loose, ref_dup);
}
git_iterator_free(fsit);
git_buf_free(&path);
return error;
}
static int refdb_fs_backend__iterator_next(
git_reference **out, git_reference_iterator *_iter)
{
int error = GIT_ITEROVER;
refdb_fs_iter *iter = (refdb_fs_iter *)_iter;
refdb_fs_backend *backend = (refdb_fs_backend *)iter->parent.db->backend;
struct packref *ref;
while (iter->loose_pos < iter->loose.length) {
const char *path = git_vector_get(&iter->loose, iter->loose_pos++);
if (loose_lookup(out, backend, path) == 0)
return 0;
giterr_clear();
}
if (!iter->cache) {
if ((error = git_sortedcache_copy(&iter->cache, backend->refcache, 1, NULL, NULL)) < 0)
return error;
}
error = GIT_ITEROVER;
while (iter->packed_pos < git_sortedcache_entrycount(iter->cache)) {
ref = git_sortedcache_entry(iter->cache, iter->packed_pos++);
if (!ref) /* stop now if another thread deleted refs and we past end */
break;
if (ref->flags & PACKREF_SHADOWED)
continue;
if (iter->glob && p_fnmatch(iter->glob, ref->name, 0) != 0)
continue;
*out = git_reference__alloc(ref->name, &ref->oid, &ref->peel);
error = (*out != NULL) ? 0 : -1;
break;
}
return error;
}
static int refdb_fs_backend__iterator_next_name(
const char **out, git_reference_iterator *_iter)
{
int error = GIT_ITEROVER;
refdb_fs_iter *iter = (refdb_fs_iter *)_iter;
refdb_fs_backend *backend = (refdb_fs_backend *)iter->parent.db->backend;
struct packref *ref;
while (iter->loose_pos < iter->loose.length) {
const char *path = git_vector_get(&iter->loose, iter->loose_pos++);
if (loose_lookup(NULL, backend, path) == 0) {
*out = path;
return 0;
}
giterr_clear();
}
if (!iter->cache) {
if ((error = git_sortedcache_copy(&iter->cache, backend->refcache, 1, NULL, NULL)) < 0)
return error;
}
error = GIT_ITEROVER;
while (iter->packed_pos < git_sortedcache_entrycount(iter->cache)) {
ref = git_sortedcache_entry(iter->cache, iter->packed_pos++);
if (!ref) /* stop now if another thread deleted refs and we past end */
break;
if (ref->flags & PACKREF_SHADOWED)
continue;
if (iter->glob && p_fnmatch(iter->glob, ref->name, 0) != 0)
continue;
*out = ref->name;
error = 0;
break;
}
return error;
}
static int refdb_fs_backend__iterator(
git_reference_iterator **out, git_refdb_backend *_backend, const char *glob)
{
int error;
refdb_fs_iter *iter;
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
assert(backend);
if ((error = packed_reload(backend)) < 0)
return error;
iter = git__calloc(1, sizeof(refdb_fs_iter));
GITERR_CHECK_ALLOC(iter);
git_pool_init(&iter->pool, 1);
if (git_vector_init(&iter->loose, 8, NULL) < 0)
goto fail;
if (glob != NULL &&
(iter->glob = git_pool_strdup(&iter->pool, glob)) == NULL)
goto fail;
iter->parent.next = refdb_fs_backend__iterator_next;
iter->parent.next_name = refdb_fs_backend__iterator_next_name;
iter->parent.free = refdb_fs_backend__iterator_free;
if (iter_load_loose_paths(backend, iter) < 0)
goto fail;
*out = (git_reference_iterator *)iter;
return 0;
fail:
refdb_fs_backend__iterator_free((git_reference_iterator *)iter);
return -1;
}
static bool ref_is_available(
const char *old_ref, const char *new_ref, const char *this_ref)
{
if (old_ref == NULL || strcmp(old_ref, this_ref)) {
size_t reflen = strlen(this_ref);
size_t newlen = strlen(new_ref);
size_t cmplen = reflen < newlen ? reflen : newlen;
const char *lead = reflen < newlen ? new_ref : this_ref;
if (!strncmp(new_ref, this_ref, cmplen) && lead[cmplen] == '/') {
return false;
}
}
return true;
}
static int reference_path_available(
refdb_fs_backend *backend,
const char *new_ref,
const char* old_ref,
int force)
{
size_t i;
int error;
if ((error = packed_reload(backend)) < 0)
return error;
if (!force) {
int exists;
if ((error = refdb_fs_backend__exists(
&exists, (git_refdb_backend *)backend, new_ref)) < 0) {
return error;
}
if (exists) {
giterr_set(GITERR_REFERENCE,
"failed to write reference '%s': a reference with "
"that name already exists.", new_ref);
return GIT_EEXISTS;
}
}
git_sortedcache_rlock(backend->refcache);
for (i = 0; i < git_sortedcache_entrycount(backend->refcache); ++i) {
struct packref *ref = git_sortedcache_entry(backend->refcache, i);
if (ref && !ref_is_available(old_ref, new_ref, ref->name)) {
git_sortedcache_runlock(backend->refcache);
giterr_set(GITERR_REFERENCE,
"path to reference '%s' collides with existing one", new_ref);
return -1;
}
}
git_sortedcache_runlock(backend->refcache);
return 0;
}
static int loose_lock(git_filebuf *file, refdb_fs_backend *backend, const char *name)
{
int error, filebuf_flags;
git_buf ref_path = GIT_BUF_INIT;
const char *basedir;
assert(file && backend && name);
if (!git_path_isvalid(backend->repo, name, GIT_PATH_REJECT_FILESYSTEM_DEFAULTS)) {
giterr_set(GITERR_INVALID, "invalid reference name '%s'", name);
return GIT_EINVALIDSPEC;
}
if (is_per_worktree_ref(name))
basedir = backend->gitpath;
else
basedir = backend->commonpath;
/* Remove a possibly existing empty directory hierarchy
* which name would collide with the reference name
*/
if ((error = git_futils_rmdir_r(name, basedir, GIT_RMDIR_SKIP_NONEMPTY)) < 0)
return error;
if (git_buf_joinpath(&ref_path, basedir, name) < 0)
return -1;
filebuf_flags = GIT_FILEBUF_FORCE;
if (backend->fsync)
filebuf_flags |= GIT_FILEBUF_FSYNC;
error = git_filebuf_open(file, ref_path.ptr, filebuf_flags, GIT_REFS_FILE_MODE);
if (error == GIT_EDIRECTORY)
giterr_set(GITERR_REFERENCE, "cannot lock ref '%s', there are refs beneath that folder", name);
git_buf_free(&ref_path);
return error;
}
static int loose_commit(git_filebuf *file, const git_reference *ref)
{
assert(file && ref);
if (ref->type == GIT_REF_OID) {
char oid[GIT_OID_HEXSZ + 1];
git_oid_nfmt(oid, sizeof(oid), &ref->target.oid);
git_filebuf_printf(file, "%s\n", oid);
} else if (ref->type == GIT_REF_SYMBOLIC) {
git_filebuf_printf(file, GIT_SYMREF "%s\n", ref->target.symbolic);
} else {
assert(0); /* don't let this happen */
}
return git_filebuf_commit(file);
}
static int refdb_fs_backend__lock(void **out, git_refdb_backend *_backend, const char *refname)
{
int error;
git_filebuf *lock;
refdb_fs_backend *backend = (refdb_fs_backend *) _backend;
lock = git__calloc(1, sizeof(git_filebuf));
GITERR_CHECK_ALLOC(lock);
if ((error = loose_lock(lock, backend, refname)) < 0) {
git__free(lock);
return error;
}
*out = lock;
return 0;
}
static int refdb_fs_backend__write_tail(
git_refdb_backend *_backend,
const git_reference *ref,
git_filebuf *file,
int update_reflog,
const git_signature *who,
const char *message,
const git_oid *old_id,
const char *old_target);
static int refdb_fs_backend__delete_tail(
git_refdb_backend *_backend,
git_filebuf *file,
const char *ref_name,
const git_oid *old_id, const char *old_target);
static int refdb_fs_backend__unlock(git_refdb_backend *backend, void *payload, int success, int update_reflog,
const git_reference *ref, const git_signature *sig, const char *message)
{
git_filebuf *lock = (git_filebuf *) payload;
int error = 0;
if (success == 2)
error = refdb_fs_backend__delete_tail(backend, lock, ref->name, NULL, NULL);
else if (success)
error = refdb_fs_backend__write_tail(backend, ref, lock, update_reflog, sig, message, NULL, NULL);
else
git_filebuf_cleanup(lock);
git__free(lock);
return error;
}
/*
* Find out what object this reference resolves to.
*
* For references that point to a 'big' tag (e.g. an
* actual tag object on the repository), we need to
* cache on the packfile the OID of the object to
* which that 'big tag' is pointing to.
*/
static int packed_find_peel(refdb_fs_backend *backend, struct packref *ref)
{
git_object *object;
if (ref->flags & PACKREF_HAS_PEEL || ref->flags & PACKREF_CANNOT_PEEL)
return 0;
/*
* Find the tagged object in the repository
*/
if (git_object_lookup(&object, backend->repo, &ref->oid, GIT_OBJ_ANY) < 0)
return -1;
/*
* If the tagged object is a Tag object, we need to resolve it;
* if the ref is actually a 'weak' ref, we don't need to resolve
* anything.
*/
if (git_object_type(object) == GIT_OBJ_TAG) {
git_tag *tag = (git_tag *)object;
/*
* Find the object pointed at by this tag
*/
git_oid_cpy(&ref->peel, git_tag_target_id(tag));
ref->flags |= PACKREF_HAS_PEEL;
/*
* The reference has now cached the resolved OID, and is
* marked at such. When written to the packfile, it'll be
* accompanied by this resolved oid
*/
}
git_object_free(object);
return 0;
}
/*
* Write a single reference into a packfile
*/
static int packed_write_ref(struct packref *ref, git_filebuf *file)
{
char oid[GIT_OID_HEXSZ + 1];
git_oid_nfmt(oid, sizeof(oid), &ref->oid);
/*
* For references that peel to an object in the repo, we must
* write the resulting peel on a separate line, e.g.
*
* 6fa8a902cc1d18527e1355773c86721945475d37 refs/tags/libgit2-0.4
* ^2ec0cb7959b0bf965d54f95453f5b4b34e8d3100
*
* This obviously only applies to tags.
* The required peels have already been loaded into `ref->peel_target`.
*/
if (ref->flags & PACKREF_HAS_PEEL) {
char peel[GIT_OID_HEXSZ + 1];
git_oid_nfmt(peel, sizeof(peel), &ref->peel);
if (git_filebuf_printf(file, "%s %s\n^%s\n", oid, ref->name, peel) < 0)
return -1;
} else {
if (git_filebuf_printf(file, "%s %s\n", oid, ref->name) < 0)
return -1;
}
return 0;
}
/*
* Remove all loose references
*
* Once we have successfully written a packfile,
* all the loose references that were packed must be
* removed from disk.
*
* This is a dangerous method; make sure the packfile
* is well-written, because we are destructing references
* here otherwise.
*/
static int packed_remove_loose(refdb_fs_backend *backend)
{
size_t i;
git_filebuf lock = GIT_FILEBUF_INIT;
git_buf ref_content = GIT_BUF_INIT;
int error = 0;
/* backend->refcache is already locked when this is called */
for (i = 0; i < git_sortedcache_entrycount(backend->refcache); ++i) {
struct packref *ref = git_sortedcache_entry(backend->refcache, i);
git_oid current_id;
if (!ref || !(ref->flags & PACKREF_WAS_LOOSE))
continue;
git_filebuf_cleanup(&lock);
/* We need to stop anybody from updating the ref while we try to do a safe delete */
error = loose_lock(&lock, backend, ref->name);
/* If someone else is updating it, let them do it */
if (error == GIT_EEXISTS || error == GIT_ENOTFOUND)
continue;
if (error < 0) {
git_buf_free(&ref_content);
giterr_set(GITERR_REFERENCE, "failed to lock loose reference '%s'", ref->name);
return error;
}
error = git_futils_readbuffer(&ref_content, lock.path_original);
/* Someone else beat us to cleaning up the ref, let's simply continue */
if (error == GIT_ENOTFOUND)
continue;
/* This became a symref between us packing and trying to delete it, so ignore it */
if (!git__prefixcmp(ref_content.ptr, GIT_SYMREF))
continue;
/* Figure out the current id; if we find a bad ref file, skip it so we can do the rest */
if (loose_parse_oid(¤t_id, lock.path_original, &ref_content) < 0)
continue;
/* If the ref moved since we packed it, we must not delete it */
if (!git_oid_equal(¤t_id, &ref->oid))
continue;
/*
* if we fail to remove a single file, this is *not* good,
* but we should keep going and remove as many as possible.
* If we fail to remove, the ref is still in the old state, so
* we haven't lost information.
*/
p_unlink(lock.path_original);
}
git_buf_free(&ref_content);
git_filebuf_cleanup(&lock);
return 0;
}
/*
* Write all the contents in the in-memory packfile to disk.
*/
static int packed_write(refdb_fs_backend *backend)