*/
unsigned int referrers;
- /*
- * Iff the packed-refs file associated with this instance is
- * currently locked for writing, this points at the associated
- * lock (which is owned by somebody else). The referrer count
- * is also incremented when the file is locked and decremented
- * when it is unlocked.
- */
- struct lock_file *lock;
-
/* The metadata from when this packed-refs cache was read */
struct stat_validity validity;
};
struct ref_cache *loose;
struct packed_ref_cache *packed;
-};
-/* Lock used for the main packed-refs file: */
-static struct lock_file packlock;
+ /*
+ * Lock used for the "packed-refs" file. Note that this (and
+ * thus the enclosing `files_ref_store`) must not be freed.
+ */
+ struct lock_file packed_refs_lock;
+};
/*
* Increment the reference count of *packed_refs.
if (refs->packed) {
struct packed_ref_cache *packed_refs = refs->packed;
- if (packed_refs->lock)
- die("internal error: packed-ref cache cleared while locked");
+ if (is_lock_file_locked(&refs->packed_refs_lock))
+ die("BUG: packed-ref cache cleared while locked");
refs->packed = NULL;
release_packed_ref_cache(packed_refs);
}
}
/*
- * Read f, which is a packed-refs file, into dir.
+ * Read from `packed_refs_file` into a newly-allocated
+ * `packed_ref_cache` and return it. The return value will already
+ * have its reference count incremented.
*
* A comment line of the form "# pack-refs with: " may contain zero or
* more traits. We interpret the traits as follows:
* compatibility with older clients, but we do not require it
* (i.e., "peeled" is a no-op if "fully-peeled" is set).
*/
-static void read_packed_refs(FILE *f, struct ref_dir *dir)
+static struct packed_ref_cache *read_packed_refs(const char *packed_refs_file)
{
+ FILE *f;
+ struct packed_ref_cache *packed_refs = xcalloc(1, sizeof(*packed_refs));
struct ref_entry *last = NULL;
struct strbuf line = STRBUF_INIT;
enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
+ struct ref_dir *dir;
+
+ acquire_packed_ref_cache(packed_refs);
+ packed_refs->cache = create_ref_cache(NULL, NULL);
+ packed_refs->cache->root->flag &= ~REF_INCOMPLETE;
+
+ f = fopen(packed_refs_file, "r");
+ if (!f) {
+ if (errno == ENOENT) {
+ /*
+ * This is OK; it just means that no
+ * "packed-refs" file has been written yet,
+ * which is equivalent to it being empty.
+ */
+ return packed_refs;
+ } else {
+ die_errno("couldn't read %s", packed_refs_file);
+ }
+ }
+
+ stat_validity_update(&packed_refs->validity, fileno(f));
+ dir = get_ref_dir(packed_refs->cache->root);
while (strbuf_getwholeline(&line, f, '\n') != EOF) {
struct object_id oid;
const char *refname;
oidclr(&oid);
flag |= REF_BAD_NAME | REF_ISBROKEN;
}
- last = create_ref_entry(refname, &oid, flag, 0);
+ last = create_ref_entry(refname, &oid, flag);
if (peeled == PEELED_FULLY ||
(peeled == PEELED_TAGS && starts_with(refname, "refs/tags/")))
last->flag |= REF_KNOWS_PEELED;
}
}
+ fclose(f);
strbuf_release(&line);
+
+ return packed_refs;
}
static const char *files_packed_refs_path(struct files_ref_store *refs)
/*
* Get the packed_ref_cache for the specified files_ref_store,
- * creating it if necessary.
+ * creating and populating it if it hasn't been read before or if the
+ * file has been changed (according to its `validity` field) since it
+ * was last read. On the other hand, if we hold the lock, then assume
+ * that the file hasn't been changed out from under us, so skip the
+ * extra `stat()` call in `stat_validity_check()`.
*/
static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *refs)
{
const char *packed_refs_file = files_packed_refs_path(refs);
if (refs->packed &&
+ !is_lock_file_locked(&refs->packed_refs_lock) &&
!stat_validity_check(&refs->packed->validity, packed_refs_file))
clear_packed_ref_cache(refs);
- if (!refs->packed) {
- FILE *f;
-
- refs->packed = xcalloc(1, sizeof(*refs->packed));
- acquire_packed_ref_cache(refs->packed);
- refs->packed->cache = create_ref_cache(&refs->base, NULL);
- refs->packed->cache->root->flag &= ~REF_INCOMPLETE;
- f = fopen(packed_refs_file, "r");
- if (f) {
- stat_validity_update(&refs->packed->validity, fileno(f));
- read_packed_refs(f, get_ref_dir(refs->packed->cache->root));
- fclose(f);
- }
- }
+ if (!refs->packed)
+ refs->packed = read_packed_refs(packed_refs_file);
+
return refs->packed;
}
{
struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);
- if (!packed_ref_cache->lock)
- die("internal error: packed refs not locked");
+ if (!is_lock_file_locked(&refs->packed_refs_lock))
+ die("BUG: packed refs not locked");
+
+ if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
+ die("Reference has invalid format: '%s'", refname);
+
add_ref_entry(get_packed_ref_dir(packed_ref_cache),
- create_ref_entry(refname, oid, REF_ISPACKED, 1));
+ create_ref_entry(refname, oid, REF_ISPACKED));
}
/*
flag |= REF_BAD_NAME | REF_ISBROKEN;
}
add_entry_to_dir(dir,
- create_ref_entry(refname.buf, &oid, flag, 0));
+ create_ref_entry(refname.buf, &oid, flag));
}
strbuf_setlen(&refname, dirnamelen);
strbuf_setlen(&path, path_baselen);
struct ref_iterator *loose_iter, *packed_iter;
struct files_ref_iterator *iter;
struct ref_iterator *ref_iterator;
+ unsigned int required_flags = REF_STORE_READ;
- if (ref_paranoia < 0)
- ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
- if (ref_paranoia)
- flags |= DO_FOR_EACH_INCLUDE_BROKEN;
+ if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN))
+ required_flags |= REF_STORE_ODB;
- refs = files_downcast(ref_store,
- REF_STORE_READ | (ref_paranoia ? 0 : REF_STORE_ODB),
- "ref_iterator_begin");
+ refs = files_downcast(ref_store, required_flags, "ref_iterator_begin");
iter = xcalloc(1, sizeof(*iter));
ref_iterator = &iter->base;
}
if (hold_lock_file_for_update_timeout(
- &packlock, files_packed_refs_path(refs),
+ &refs->packed_refs_lock, files_packed_refs_path(refs),
flags, timeout_value) < 0)
return -1;
/*
- * Get the current packed-refs while holding the lock. If the
- * packed-refs file has been modified since we last read it,
- * this will automatically invalidate the cache and re-read
- * the packed-refs file.
+ * Get the current packed-refs while holding the lock. It is
+ * important that we call `get_packed_ref_cache()` before
+ * setting `packed_ref_cache->lock`, because otherwise the
+ * former will see that the file is locked and assume that the
+ * cache can't be stale.
*/
packed_ref_cache = get_packed_ref_cache(refs);
- packed_ref_cache->lock = &packlock;
/* Increment the reference count to prevent it from being freed: */
acquire_packed_ref_cache(packed_ref_cache);
return 0;
files_assert_main_repository(refs, "commit_packed_refs");
- if (!packed_ref_cache->lock)
- die("internal error: packed-refs not locked");
+ if (!is_lock_file_locked(&refs->packed_refs_lock))
+ die("BUG: packed-refs not locked");
- out = fdopen_lock_file(packed_ref_cache->lock, "w");
+ out = fdopen_lock_file(&refs->packed_refs_lock, "w");
if (!out)
die_errno("unable to fdopen packed-refs descriptor");
if (ok != ITER_DONE)
die("error while iterating over references");
- if (commit_lock_file(packed_ref_cache->lock)) {
+ if (commit_lock_file(&refs->packed_refs_lock)) {
save_errno = errno;
error = -1;
}
- packed_ref_cache->lock = NULL;
release_packed_ref_cache(packed_ref_cache);
errno = save_errno;
return error;
files_assert_main_repository(refs, "rollback_packed_refs");
- if (!packed_ref_cache->lock)
- die("internal error: packed-refs not locked");
- rollback_lock_file(packed_ref_cache->lock);
- packed_ref_cache->lock = NULL;
+ if (!is_lock_file_locked(&refs->packed_refs_lock))
+ die("BUG: packed-refs not locked");
+ rollback_lock_file(&refs->packed_refs_lock);
release_packed_ref_cache(packed_ref_cache);
clear_packed_ref_cache(refs);
}
}
}
+/*
+ * Return true if the specified reference should be packed.
+ */
+static int should_pack_ref(const char *refname,
+ const struct object_id *oid, unsigned int ref_flags,
+ unsigned int pack_flags)
+{
+ /* Do not pack per-worktree refs: */
+ if (ref_type(refname) != REF_TYPE_NORMAL)
+ return 0;
+
+ /* Do not pack non-tags unless PACK_REFS_ALL is set: */
+ if (!(pack_flags & PACK_REFS_ALL) && !starts_with(refname, "refs/tags/"))
+ return 0;
+
+ /* Do not pack symbolic refs: */
+ if (ref_flags & REF_ISSYMREF)
+ return 0;
+
+ /* Do not pack broken refs: */
+ if (!ref_resolves_to_object(refname, oid, ref_flags))
+ return 0;
+
+ return 1;
+}
+
static int files_pack_refs(struct ref_store *ref_store, unsigned int flags)
{
struct files_ref_store *refs =
* pruned, also add it to refs_to_prune.
*/
struct ref_entry *packed_entry;
- int is_tag_ref = starts_with(iter->refname, "refs/tags/");
-
- /* Do not pack per-worktree refs: */
- if (ref_type(iter->refname) != REF_TYPE_NORMAL)
- continue;
-
- /* ALWAYS pack tags */
- if (!(flags & PACK_REFS_ALL) && !is_tag_ref)
- continue;
-
- /* Do not pack symbolic or broken refs: */
- if (iter->flags & REF_ISSYMREF)
- continue;
- if (!ref_resolves_to_object(iter->refname, iter->oid, iter->flags))
+ if (!should_pack_ref(iter->refname, iter->oid, iter->flags,
+ flags))
continue;
/*
oidcpy(&packed_entry->u.value.oid, iter->oid);
} else {
packed_entry = create_ref_entry(iter->refname, iter->oid,
- REF_ISPACKED, 0);
+ REF_ISPACKED);
add_ref_entry(packed_refs, packed_entry);
}
oidclr(&packed_entry->u.value.peeled);
return ret;
}
-static int files_delete_refs(struct ref_store *ref_store,
+static int files_delete_refs(struct ref_store *ref_store, const char *msg,
struct string_list *refnames, unsigned int flags)
{
struct files_ref_store *refs =
for (i = 0; i < refnames->nr; i++) {
const char *refname = refnames->items[i].string;
- if (refs_delete_ref(&refs->base, NULL, refname, NULL, flags))
+ if (refs_delete_ref(&refs->base, msg, refname, NULL, flags))
result |= error(_("could not remove reference %s"), refname);
}
return ref_iterator;
}
-static int ref_update_reject_duplicates(struct string_list *refnames,
- struct strbuf *err)
-{
- int i, n = refnames->nr;
-
- assert(err);
-
- for (i = 1; i < n; i++)
- if (!strcmp(refnames->items[i - 1].string, refnames->items[i].string)) {
- strbuf_addf(err,
- "multiple updates for ref '%s' not allowed.",
- refnames->items[i].string);
- return 1;
- }
- return 0;
-}
-
/*
* If update is a direct update of head_ref (the reference pointed to
* by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
return 0;
}
-static int files_transaction_commit(struct ref_store *ref_store,
- struct ref_transaction *transaction,
- struct strbuf *err)
+/*
+ * Unlock any references in `transaction` that are still locked, and
+ * mark the transaction closed.
+ */
+static void files_transaction_cleanup(struct ref_transaction *transaction)
+{
+ size_t i;
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *update = transaction->updates[i];
+ struct ref_lock *lock = update->backend_data;
+
+ if (lock) {
+ unlock_ref(lock);
+ update->backend_data = NULL;
+ }
+ }
+
+ transaction->state = REF_TRANSACTION_CLOSED;
+}
+
+static int files_transaction_prepare(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
{
struct files_ref_store *refs =
files_downcast(ref_store, REF_STORE_WRITE,
- "ref_transaction_commit");
- int ret = 0, i;
- struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
- struct string_list_item *ref_to_delete;
+ "ref_transaction_prepare");
+ size_t i;
+ int ret = 0;
struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
char *head_ref = NULL;
int head_type;
struct object_id head_oid;
- struct strbuf sb = STRBUF_INIT;
assert(err);
- if (transaction->state != REF_TRANSACTION_OPEN)
- die("BUG: commit called for transaction that is not open");
-
- if (!transaction->nr) {
- transaction->state = REF_TRANSACTION_CLOSED;
- return 0;
- }
+ if (!transaction->nr)
+ goto cleanup;
/*
* Fail if a refname appears more than once in the
head_oid.hash, &head_type);
if (head_ref && !(head_type & REF_ISSYMREF)) {
- free(head_ref);
- head_ref = NULL;
+ FREE_AND_NULL(head_ref);
}
/*
* that new values are valid, and write new values to the
* lockfiles, ready to be activated. Only keep one lockfile
* open at a time to avoid running out of file descriptors.
+ * Note that lock_ref_for_update() might append more updates
+ * to the transaction.
*/
for (i = 0; i < transaction->nr; i++) {
struct ref_update *update = transaction->updates[i];
ret = lock_ref_for_update(refs, update, transaction,
head_ref, &affected_refnames, err);
if (ret)
- goto cleanup;
+ break;
+ }
+
+cleanup:
+ free(head_ref);
+ string_list_clear(&affected_refnames, 0);
+
+ if (ret)
+ files_transaction_cleanup(transaction);
+ else
+ transaction->state = REF_TRANSACTION_PREPARED;
+
+ return ret;
+}
+
+static int files_transaction_finish(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ struct files_ref_store *refs =
+ files_downcast(ref_store, 0, "ref_transaction_finish");
+ size_t i;
+ int ret = 0;
+ struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
+ struct string_list_item *ref_to_delete;
+ struct strbuf sb = STRBUF_INIT;
+
+ assert(err);
+
+ if (!transaction->nr) {
+ transaction->state = REF_TRANSACTION_CLOSED;
+ return 0;
}
/* Perform updates first so live commits remain referenced */
clear_loose_ref_cache(refs);
cleanup:
- strbuf_release(&sb);
- transaction->state = REF_TRANSACTION_CLOSED;
+ files_transaction_cleanup(transaction);
for (i = 0; i < transaction->nr; i++) {
struct ref_update *update = transaction->updates[i];
- struct ref_lock *lock = update->backend_data;
-
- if (lock)
- unlock_ref(lock);
if (update->flags & REF_DELETED_LOOSE) {
/*
}
}
+ strbuf_release(&sb);
string_list_clear(&refs_to_delete, 0);
- free(head_ref);
- string_list_clear(&affected_refnames, 0);
-
return ret;
}
+static int files_transaction_abort(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ files_transaction_cleanup(transaction);
+ return 0;
+}
+
static int ref_present(const char *refname,
const struct object_id *oid, int flags, void *cb_data)
{
struct files_ref_store *refs =
files_downcast(ref_store, REF_STORE_WRITE,
"initial_ref_transaction_commit");
- int ret = 0, i;
+ size_t i;
+ int ret = 0;
struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
assert(err);
"files",
files_ref_store_create,
files_init_db,
- files_transaction_commit,
+ files_transaction_prepare,
+ files_transaction_finish,
+ files_transaction_abort,
files_initial_transaction_commit,
files_pack_refs,