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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 <git2/tag.h>
#include <git2/object.h>
#include <git2/refdb.h>
#include <git2/sys/refdb_backend.h>
#include <git2/sys/refs.h>
GIT__USE_STRMAP;
#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;
char *path;
git_sortedcache *refcache;
int peeling_mode;
} refdb_fs_backend;
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->path)
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->path, 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 *data, git_buf *full_path)
{
refdb_fs_backend *backend = (refdb_fs_backend *)data;
const char *file_path;
if (git__suffixcmp(full_path->ptr, ".lock") == 0)
return 0;
if (git_path_isdir(full_path->ptr))
return git_path_direach(full_path, _dirent_loose_load, backend);
file_path = full_path->ptr + strlen(backend->path);
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->path, 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, _dirent_loose_load, backend);
git_buf_free(&refs_path);
return (error == GIT_EUSER) ? -1 : 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;
assert(backend);
if (packed_reload(backend) < 0 ||
git_buf_joinpath(&ref_path, backend->path, ref_name) < 0)
return -1;
*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;
}
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;
if (out)
*out = NULL;
if ((error = loose_readbuffer(&ref_file, backend->path, 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 (packed_reload(backend) < 0)
return -1;
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;
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__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;
const git_index_entry *entry = NULL;
if (!backend->path) /* do nothing if no path for loose refs */
return 0;
if ((error = git_buf_printf(&path, "%s/refs", backend->path)) < 0 ||
(error = git_iterator_for_filesystem(
&fsit, git_buf_cstr(&path), 0, NULL, NULL)) < 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();
}
git_sortedcache_rlock(backend->refcache);
while (iter->packed_pos < git_sortedcache_entrycount(backend->refcache)) {
ref = git_sortedcache_entry(backend->refcache, 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;
}
git_sortedcache_runlock(backend->refcache);
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();
}
git_sortedcache_rlock(backend->refcache);
while (iter->packed_pos < git_sortedcache_entrycount(backend->refcache)) {
ref = git_sortedcache_entry(backend->refcache, 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;
}
git_sortedcache_runlock(backend->refcache);
return error;
}
static int refdb_fs_backend__iterator(
git_reference_iterator **out, git_refdb_backend *_backend, const char *glob)
{
refdb_fs_iter *iter;
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
assert(backend);
if (packed_reload(backend) < 0)
return -1;
iter = git__calloc(1, sizeof(refdb_fs_iter));
GITERR_CHECK_ALLOC(iter);
if (git_pool_init(&iter->pool, 1, 0) < 0 ||
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;
if (packed_reload(backend) < 0)
return -1;
if (!force) {
int exists;
if (refdb_fs_backend__exists(
&exists, (git_refdb_backend *)backend, new_ref) < 0)
return -1;
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_write(refdb_fs_backend *backend, const git_reference *ref)
{
git_filebuf file = GIT_FILEBUF_INIT;
git_buf ref_path = GIT_BUF_INIT;
/* Remove a possibly existing empty directory hierarchy
* which name would collide with the reference name
*/
if (git_futils_rmdir_r(ref->name, backend->path, GIT_RMDIR_SKIP_NONEMPTY) < 0)
return -1;
if (git_buf_joinpath(&ref_path, backend->path, ref->name) < 0)
return -1;
if (git_filebuf_open(&file, ref_path.ptr, GIT_FILEBUF_FORCE) < 0) {
git_buf_free(&ref_path);
return -1;
}
git_buf_free(&ref_path);
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, GIT_REFS_FILE_MODE);
}
/*
* 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_buf full_path = GIT_BUF_INIT;
int failed = 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);
if (!ref || !(ref->flags & PACKREF_WAS_LOOSE))
continue;
if (git_buf_joinpath(&full_path, backend->path, ref->name) < 0)
return -1; /* critical; do not try to recover on oom */
if (git_path_exists(full_path.ptr) && p_unlink(full_path.ptr) < 0) {
if (failed)
continue;
giterr_set(GITERR_REFERENCE,
"Failed to remove loose reference '%s' after packing: %s",
full_path.ptr, strerror(errno));
failed = 1;
}
/*
* if we fail to remove a single file, this is *not* good,
* but we should keep going and remove as many as possible.
* After we've removed as many files as possible, we return
* the error code anyway.
*/
}
git_buf_free(&full_path);
return failed ? -1 : 0;
}
/*
* Write all the contents in the in-memory packfile to disk.
*/
static int packed_write(refdb_fs_backend *backend)
{
git_sortedcache *refcache = backend->refcache;
git_filebuf pack_file = GIT_FILEBUF_INIT;
size_t i;
/* lock the cache to updates while we do this */
if (git_sortedcache_wlock(refcache) < 0)
return -1;
/* Open the file! */
if (git_filebuf_open(&pack_file, git_sortedcache_path(refcache), 0) < 0)
goto fail;
/* Packfiles have a header... apparently
* This is in fact not required, but we might as well print it
* just for kicks */
if (git_filebuf_printf(&pack_file, "%s\n", GIT_PACKEDREFS_HEADER) < 0)
goto fail;
for (i = 0; i < git_sortedcache_entrycount(refcache); ++i) {
struct packref *ref = git_sortedcache_entry(refcache, i);
if (packed_find_peel(backend, ref) < 0)
goto fail;
if (packed_write_ref(ref, &pack_file) < 0)
goto fail;
}
/* if we've written all the references properly, we can commit
* the packfile to make the changes effective */
if (git_filebuf_commit(&pack_file, GIT_PACKEDREFS_FILE_MODE) < 0)
goto fail;
/* when and only when the packfile has been properly written,
* we can go ahead and remove the loose refs */
if (packed_remove_loose(backend) < 0)
goto fail;
git_sortedcache_updated(refcache);
git_sortedcache_wunlock(refcache);
/* we're good now */
return 0;
fail:
git_filebuf_cleanup(&pack_file);
git_sortedcache_wunlock(refcache);
return -1;
}
static int refdb_fs_backend__write(
git_refdb_backend *_backend,
const git_reference *ref,
int force)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
int error;
assert(backend);
error = reference_path_available(backend, ref->name, NULL, force);
if (error < 0)
return error;
return loose_write(backend, ref);
}
static int refdb_fs_backend__delete(
git_refdb_backend *_backend,
const char *ref_name)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
git_buf loose_path = GIT_BUF_INIT;
size_t pack_pos;
int error = 0;
bool loose_deleted = 0;
assert(backend && ref_name);
/* If a loose reference exists, remove it from the filesystem */
if (git_buf_joinpath(&loose_path, backend->path, ref_name) < 0)
return -1;
if (git_path_isfile(loose_path.ptr)) {
error = p_unlink(loose_path.ptr);
loose_deleted = 1;
}
git_buf_free(&loose_path);
if (error != 0)
return error;
if (packed_reload(backend) < 0)
return -1;
/* If a packed reference exists, remove it from the packfile and repack */
if (git_sortedcache_wlock(backend->refcache) < 0)
return -1;
if (!(error = git_sortedcache_lookup_index(
&pack_pos, backend->refcache, ref_name)))
error = git_sortedcache_remove(backend->refcache, pack_pos);
git_sortedcache_wunlock(backend->refcache);
if (error == GIT_ENOTFOUND)
return loose_deleted ? 0 : ref_error_notfound(ref_name);
return packed_write(backend);
}
static int refdb_fs_backend__rename(
git_reference **out,
git_refdb_backend *_backend,
const char *old_name,
const char *new_name,
int force)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
git_reference *old, *new;
int error;
assert(backend);
if ((error = reference_path_available(
backend, new_name, old_name, force)) < 0 ||
(error = refdb_fs_backend__lookup(&old, _backend, old_name)) < 0)
return error;
if ((error = refdb_fs_backend__delete(_backend, old_name)) < 0) {
git_reference_free(old);
return error;
}
new = git_reference__set_name(old, new_name);
if (!new) {
git_reference_free(old);
return -1;
}
if ((error = loose_write(backend, new)) < 0 || out == NULL) {
git_reference_free(new);
return error;
}
*out = new;
return 0;
}
static int refdb_fs_backend__compress(git_refdb_backend *_backend)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
assert(backend);
if (packed_reload(backend) < 0 || /* load the existing packfile */
packed_loadloose(backend) < 0 || /* add all the loose refs */
packed_write(backend) < 0) /* write back to disk */
return -1;
return 0;
}
static void refdb_fs_backend__free(git_refdb_backend *_backend)
{
refdb_fs_backend *backend = (refdb_fs_backend *)_backend;
assert(backend);
git_sortedcache_free(backend->refcache);
git__free(backend->path);
git__free(backend);
}
static int setup_namespace(git_buf *path, git_repository *repo)
{
char *parts, *start, *end;
/* Not all repositories have a path */
if (repo->path_repository == NULL)
return 0;
/* Load the path to the repo first */
git_buf_puts(path, repo->path_repository);
/* if the repo is not namespaced, nothing else to do */
if (repo->namespace == NULL)
return 0;
parts = end = git__strdup(repo->namespace);
if (parts == NULL)
return -1;
/*
* From `man gitnamespaces`:
* namespaces which include a / will expand to a hierarchy
* of namespaces; for example, GIT_NAMESPACE=foo/bar will store
* refs under refs/namespaces/foo/refs/namespaces/bar/
*/
while ((start = git__strsep(&end, "/")) != NULL) {
git_buf_printf(path, "refs/namespaces/%s/", start);
}
git_buf_printf(path, "refs/namespaces/%s/refs", end);
git__free(parts);
/* Make sure that the folder with the namespace exists */
if (git_futils_mkdir_r(git_buf_cstr(path), repo->path_repository, 0777) < 0)
return -1;
/* Return root of the namespaced path, i.e. without the trailing '/refs' */
git_buf_rtruncate_at_char(path, '/');
return 0;
}
int git_refdb_backend_fs(
git_refdb_backend **backend_out,
git_repository *repository)
{
git_buf path = GIT_BUF_INIT;
refdb_fs_backend *backend;
backend = git__calloc(1, sizeof(refdb_fs_backend));
GITERR_CHECK_ALLOC(backend);
backend->repo = repository;
if (setup_namespace(&path, repository) < 0)
goto fail;
backend->path = git_buf_detach(&path);
if (git_buf_joinpath(&path, backend->path, GIT_PACKEDREFS_FILE) < 0 ||
git_sortedcache_new(
&backend->refcache, offsetof(struct packref, name),
NULL, NULL, packref_cmp, git_buf_cstr(&path)) < 0)
goto fail;
git_buf_free(&path);
backend->parent.exists = &refdb_fs_backend__exists;
backend->parent.lookup = &refdb_fs_backend__lookup;
backend->parent.iterator = &refdb_fs_backend__iterator;
backend->parent.write = &refdb_fs_backend__write;
backend->parent.del = &refdb_fs_backend__delete;
backend->parent.rename = &refdb_fs_backend__rename;
backend->parent.compress = &refdb_fs_backend__compress;
backend->parent.free = &refdb_fs_backend__free;
*backend_out = (git_refdb_backend *)backend;
return 0;
fail:
git_buf_free(&path);
git__free(backend->path);
git__free(backend);
return -1;
}
|