delete_ref_loose(): don't muck around in the lock_file's filename
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 82e5b1b14f7a6e7341dfcf8fbf61ae3982851e18..a4151315e32f38b89caa42704d16048b6c718521 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -24,6 +24,11 @@ static unsigned char refname_disposition[256] = {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
 };
 
+/*
+ * Used as a flag to ref_transaction_delete when a loose ref is being
+ * pruned.
+ */
+#define REF_ISPRUNING  0x0100
 /*
  * Try to read one refname component from the front of refname.
  * Return the length of the component found, or -1 if the component is
@@ -74,7 +79,8 @@ static int check_refname_component(const char *refname, int flags)
                if (refname[1] == '\0')
                        return -1; /* Component equals ".". */
        }
-       if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
+       if (cp - refname >= LOCK_SUFFIX_LEN &&
+           !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
                return -1; /* Refname ends with ".lock". */
        return cp - refname;
 }
@@ -779,37 +785,32 @@ static void prime_ref_dir(struct ref_dir *dir)
                        prime_ref_dir(get_ref_dir(entry));
        }
 }
-/*
- * Return true iff refname1 and refname2 conflict with each other.
- * Two reference names conflict if one of them exactly matches the
- * leading components of the other; e.g., "foo/bar" conflicts with
- * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
- * "foo/barbados".
- */
-static int names_conflict(const char *refname1, const char *refname2)
+
+static int entry_matches(struct ref_entry *entry, const char *refname)
 {
-       for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
-               ;
-       return (*refname1 == '\0' && *refname2 == '/')
-               || (*refname1 == '/' && *refname2 == '\0');
+       return refname && !strcmp(entry->name, refname);
 }
 
-struct name_conflict_cb {
-       const char *refname;
-       const char *oldrefname;
-       const char *conflicting_refname;
+struct nonmatching_ref_data {
+       const char *skip;
+       struct ref_entry *found;
 };
 
-static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
+static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata)
 {
-       struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
-       if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
+       struct nonmatching_ref_data *data = vdata;
+
+       if (entry_matches(entry, data->skip))
                return 0;
-       if (names_conflict(data->refname, entry->name)) {
-               data->conflicting_refname = entry->name;
-               return 1;
-       }
-       return 0;
+
+       data->found = entry;
+       return 1;
+}
+
+static void report_refname_conflict(struct ref_entry *entry,
+                                   const char *refname)
+{
+       error("'%s' exists; cannot create '%s'", entry->name, refname);
 }
 
 /*
@@ -818,21 +819,84 @@ static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
  * oldrefname is non-NULL, ignore potential conflicts with oldrefname
  * (e.g., because oldrefname is scheduled for deletion in the same
  * operation).
+ *
+ * Two reference names conflict if one of them exactly matches the
+ * leading components of the other; e.g., "foo/bar" conflicts with
+ * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
+ * "foo/barbados".
  */
 static int is_refname_available(const char *refname, const char *oldrefname,
                                struct ref_dir *dir)
 {
-       struct name_conflict_cb data;
-       data.refname = refname;
-       data.oldrefname = oldrefname;
-       data.conflicting_refname = NULL;
+       const char *slash;
+       size_t len;
+       int pos;
+       char *dirname;
 
-       sort_ref_dir(dir);
-       if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
-               error("'%s' exists; cannot create '%s'",
-                     data.conflicting_refname, refname);
+       for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
+               /*
+                * We are still at a leading dir of the refname; we are
+                * looking for a conflict with a leaf entry.
+                *
+                * If we find one, we still must make sure it is
+                * not "oldrefname".
+                */
+               pos = search_ref_dir(dir, refname, slash - refname);
+               if (pos >= 0) {
+                       struct ref_entry *entry = dir->entries[pos];
+                       if (entry_matches(entry, oldrefname))
+                               return 1;
+                       report_refname_conflict(entry, refname);
+                       return 0;
+               }
+
+
+               /*
+                * Otherwise, we can try to continue our search with
+                * the next component; if we come up empty, we know
+                * there is nothing under this whole prefix.
+                */
+               pos = search_ref_dir(dir, refname, slash + 1 - refname);
+               if (pos < 0)
+                       return 1;
+
+               dir = get_ref_dir(dir->entries[pos]);
+       }
+
+       /*
+        * We are at the leaf of our refname; we want to
+        * make sure there are no directories which match it.
+        */
+       len = strlen(refname);
+       dirname = xmallocz(len + 1);
+       sprintf(dirname, "%s/", refname);
+       pos = search_ref_dir(dir, dirname, len + 1);
+       free(dirname);
+
+       if (pos >= 0) {
+               /*
+                * We found a directory named "refname". It is a
+                * problem iff it contains any ref that is not
+                * "oldrefname".
+                */
+               struct ref_entry *entry = dir->entries[pos];
+               struct ref_dir *dir = get_ref_dir(entry);
+               struct nonmatching_ref_data data;
+
+               data.skip = oldrefname;
+               sort_ref_dir(dir);
+               if (!do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data))
+                       return 1;
+
+               report_refname_conflict(data.found, refname);
                return 0;
        }
+
+       /*
+        * There is no point in searching for another leaf
+        * node which matches it; such an entry would be the
+        * ref we are looking for, not a conflict.
+        */
        return 1;
 }
 
@@ -2068,7 +2132,10 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
        return logs_found;
 }
 
-/* This function should make sure errno is meaningful on error */
+/*
+ * Locks a "refs/" ref returning the lock on success and NULL on failure.
+ * On failure errno is set to something meaningful.
+ */
 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
                                            const unsigned char *old_sha1,
                                            int flags, int *type_p)
@@ -2159,7 +2226,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
                         */
                        goto retry;
                else
-                       unable_to_lock_index_die(ref_file, errno);
+                       unable_to_lock_die(ref_file, errno);
        }
        return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
 
@@ -2169,15 +2236,6 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
        return NULL;
 }
 
-struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
-{
-       char refpath[PATH_MAX];
-       if (check_refname_format(refname, 0))
-               return NULL;
-       strcpy(refpath, mkpath("refs/%s", refname));
-       return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
-}
-
 struct ref_lock *lock_any_ref_for_update(const char *refname,
                                         const unsigned char *old_sha1,
                                         int flags, int *type_p)
@@ -2191,25 +2249,12 @@ struct ref_lock *lock_any_ref_for_update(const char *refname,
  * Write an entry to the packed-refs file for the specified refname.
  * If peeled is non-NULL, write it as the entry's peeled value.
  */
-static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
+static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1,
                               unsigned char *peeled)
 {
-       char line[PATH_MAX + 100];
-       int len;
-
-       len = snprintf(line, sizeof(line), "%s %s\n",
-                      sha1_to_hex(sha1), refname);
-       /* this should not happen but just being defensive */
-       if (len > sizeof(line))
-               die("too long a refname '%s'", refname);
-       write_or_die(fd, line, len);
-
-       if (peeled) {
-               if (snprintf(line, sizeof(line), "^%s\n",
-                            sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
-                       die("internal error");
-               write_or_die(fd, line, PEELED_LINE_LENGTH);
-       }
+       fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname);
+       if (peeled)
+               fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled));
 }
 
 /*
@@ -2217,13 +2262,12 @@ static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
  */
 static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
 {
-       int *fd = cb_data;
        enum peel_status peel_status = peel_entry(entry, 0);
 
        if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
                error("internal error: %s is not a valid packed reference!",
                      entry->name);
-       write_packed_entry(*fd, entry->name, entry->u.value.sha1,
+       write_packed_entry(cb_data, entry->name, entry->u.value.sha1,
                           peel_status == PEEL_PEELED ?
                           entry->u.value.peeled : NULL);
        return 0;
@@ -2259,15 +2303,22 @@ int commit_packed_refs(void)
                get_packed_ref_cache(&ref_cache);
        int error = 0;
        int save_errno = 0;
+       FILE *out;
 
        if (!packed_ref_cache->lock)
                die("internal error: packed-refs not locked");
-       write_or_die(packed_ref_cache->lock->fd,
-                    PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
 
+       out = fdopen(packed_ref_cache->lock->fd, "w");
+       if (!out)
+               die_errno("unable to fdopen packed-refs descriptor");
+
+       fprintf_or_die(out, "%s", PACKED_REFS_HEADER);
        do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
-                                0, write_packed_entry_fn,
-                                &packed_ref_cache->lock->fd);
+                                0, write_packed_entry_fn, out);
+       if (fclose(out))
+               die_errno("write error");
+       packed_ref_cache->lock->fd = -1;
+
        if (commit_lock_file(packed_ref_cache->lock)) {
                save_errno = errno;
                error = -1;
@@ -2387,14 +2438,25 @@ static void try_remove_empty_parents(char *name)
 /* make sure nobody touched the ref, and unlink */
 static void prune_ref(struct ref_to_prune *r)
 {
-       struct ref_lock *lock = lock_any_ref_for_update(r->name, r->sha1,
-                                                       0, NULL);
+       struct ref_transaction *transaction;
+       struct strbuf err = STRBUF_INIT;
 
-       if (lock) {
-               unlink_or_warn(git_path("%s", r->name));
-               unlock_ref(lock);
-               try_remove_empty_parents(r->name);
+       if (check_refname_format(r->name, 0))
+               return;
+
+       transaction = ref_transaction_begin(&err);
+       if (!transaction ||
+           ref_transaction_delete(transaction, r->name, r->sha1,
+                                  REF_ISPRUNING, 1, &err) ||
+           ref_transaction_commit(transaction, NULL, &err)) {
+               ref_transaction_free(transaction);
+               error("%s", err.buf);
+               strbuf_release(&err);
+               return;
        }
+       ref_transaction_free(transaction);
+       strbuf_release(&err);
+       try_remove_empty_parents(r->name);
 }
 
 static void prune_refs(struct ref_to_prune *r)
@@ -2537,20 +2599,18 @@ int repack_without_refs(const char **refnames, int n, struct strbuf *err)
        return ret;
 }
 
-static int repack_without_ref(const char *refname)
-{
-       return repack_without_refs(&refname, 1, NULL);
-}
-
 static int delete_ref_loose(struct ref_lock *lock, int flag)
 {
        if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
-               /* loose */
-               int err, i = strlen(lock->lk->filename) - 5; /* .lock */
-
-               lock->lk->filename[i] = 0;
-               err = unlink_or_warn(lock->lk->filename);
-               lock->lk->filename[i] = '.';
+               /*
+                * loose.  The loose file name is the same as the
+                * lockfile name, minus ".lock":
+                */
+               char *loose_filename = xmemdupz(
+                               lock->lk->filename,
+                               strlen(lock->lk->filename) - LOCK_SUFFIX_LEN);
+               int err = unlink_or_warn(loose_filename);
+               free(loose_filename);
                if (err && errno != ENOENT)
                        return 1;
        }
@@ -2559,24 +2619,22 @@ static int delete_ref_loose(struct ref_lock *lock, int flag)
 
 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
 {
-       struct ref_lock *lock;
-       int ret = 0, flag = 0;
-
-       lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
-       if (!lock)
+       struct ref_transaction *transaction;
+       struct strbuf err = STRBUF_INIT;
+
+       transaction = ref_transaction_begin(&err);
+       if (!transaction ||
+           ref_transaction_delete(transaction, refname, sha1, delopt,
+                                  sha1 && !is_null_sha1(sha1), &err) ||
+           ref_transaction_commit(transaction, NULL, &err)) {
+               error("%s", err.buf);
+               ref_transaction_free(transaction);
+               strbuf_release(&err);
                return 1;
-       ret |= delete_ref_loose(lock, flag);
-
-       /* removing the loose one could have resurrected an earlier
-        * packed one.  Also, if it was not loose we need to repack
-        * without it.
-        */
-       ret |= repack_without_ref(lock->ref_name);
-
-       unlink_or_warn(git_path("logs/%s", lock->ref_name));
-       clear_loose_ref_cache(&ref_cache);
-       unlock_ref(lock);
-       return ret;
+       }
+       ref_transaction_free(transaction);
+       strbuf_release(&err);
+       return 0;
 }
 
 /*
@@ -3105,7 +3163,7 @@ static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
        return 1;
 }
 
-int read_ref_at(const char *refname, unsigned long at_time, int cnt,
+int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
                unsigned char *sha1, char **msg,
                unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 {
@@ -3123,8 +3181,12 @@ int read_ref_at(const char *refname, unsigned long at_time, int cnt,
 
        for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
 
-       if (!cb.reccnt)
-               die("Log for %s is empty.", refname);
+       if (!cb.reccnt) {
+               if (flags & GET_SHA1_QUIETLY)
+                       exit(128);
+               else
+                       die("Log for %s is empty.", refname);
+       }
        if (cb.found_it)
                return 0;
 
@@ -3333,43 +3395,6 @@ int for_each_reflog(each_ref_fn fn, void *cb_data)
        return retval;
 }
 
-static struct ref_lock *update_ref_lock(const char *refname,
-                                       const unsigned char *oldval,
-                                       int flags, int *type_p,
-                                       enum action_on_err onerr)
-{
-       struct ref_lock *lock;
-       lock = lock_any_ref_for_update(refname, oldval, flags, type_p);
-       if (!lock) {
-               const char *str = "Cannot lock the ref '%s'.";
-               switch (onerr) {
-               case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
-               case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
-               case UPDATE_REFS_QUIET_ON_ERR: break;
-               }
-       }
-       return lock;
-}
-
-static int update_ref_write(const char *action, const char *refname,
-                           const unsigned char *sha1, struct ref_lock *lock,
-                           struct strbuf *err, enum action_on_err onerr)
-{
-       if (write_ref_sha1(lock, sha1, action) < 0) {
-               const char *str = "Cannot update the ref '%s'.";
-               if (err)
-                       strbuf_addf(err, str, refname);
-
-               switch (onerr) {
-               case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
-               case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
-               case UPDATE_REFS_QUIET_ON_ERR: break;
-               }
-               return 1;
-       }
-       return 0;
-}
-
 /**
  * Information needed for a single ref update.  Set new_sha1 to the
  * new value or to zero to delete the ref.  To check the old value
@@ -3386,6 +3411,21 @@ struct ref_update {
        const char refname[FLEX_ARRAY];
 };
 
+/*
+ * Transaction states.
+ * OPEN:   The transaction is in a valid state and can accept new updates.
+ *         An OPEN transaction can be committed.
+ * CLOSED: A closed transaction is no longer active and no other operations
+ *         than free can be used on it in this state.
+ *         A transaction can either become closed by successfully committing
+ *         an active transaction or if there is a failure while building
+ *         the transaction thus rendering it failed/inactive.
+ */
+enum ref_transaction_state {
+       REF_TRANSACTION_OPEN   = 0,
+       REF_TRANSACTION_CLOSED = 1
+};
+
 /*
  * Data structure for holding a reference transaction, which can
  * consist of checks and updates to multiple references, carried out
@@ -3395,9 +3435,10 @@ struct ref_transaction {
        struct ref_update **updates;
        size_t alloc;
        size_t nr;
+       enum ref_transaction_state state;
 };
 
-struct ref_transaction *ref_transaction_begin(void)
+struct ref_transaction *ref_transaction_begin(struct strbuf *err)
 {
        return xcalloc(1, sizeof(struct ref_transaction));
 }
@@ -3437,6 +3478,9 @@ int ref_transaction_update(struct ref_transaction *transaction,
 {
        struct ref_update *update;
 
+       if (transaction->state != REF_TRANSACTION_OPEN)
+               die("BUG: update called for transaction that is not open");
+
        if (have_old && !old_sha1)
                die("BUG: have_old is true but old_sha1 is NULL");
 
@@ -3449,44 +3493,84 @@ int ref_transaction_update(struct ref_transaction *transaction,
        return 0;
 }
 
-void ref_transaction_create(struct ref_transaction *transaction,
-                           const char *refname,
-                           const unsigned char *new_sha1,
-                           int flags)
+int ref_transaction_create(struct ref_transaction *transaction,
+                          const char *refname,
+                          const unsigned char *new_sha1,
+                          int flags,
+                          struct strbuf *err)
 {
-       struct ref_update *update = add_update(transaction, refname);
+       struct ref_update *update;
+
+       if (transaction->state != REF_TRANSACTION_OPEN)
+               die("BUG: create called for transaction that is not open");
+
+       if (!new_sha1 || is_null_sha1(new_sha1))
+               die("BUG: create ref with null new_sha1");
+
+       update = add_update(transaction, refname);
 
-       assert(!is_null_sha1(new_sha1));
        hashcpy(update->new_sha1, new_sha1);
        hashclr(update->old_sha1);
        update->flags = flags;
        update->have_old = 1;
+       return 0;
 }
 
-void ref_transaction_delete(struct ref_transaction *transaction,
-                           const char *refname,
-                           const unsigned char *old_sha1,
-                           int flags, int have_old)
+int ref_transaction_delete(struct ref_transaction *transaction,
+                          const char *refname,
+                          const unsigned char *old_sha1,
+                          int flags, int have_old,
+                          struct strbuf *err)
 {
-       struct ref_update *update = add_update(transaction, refname);
+       struct ref_update *update;
+
+       if (transaction->state != REF_TRANSACTION_OPEN)
+               die("BUG: delete called for transaction that is not open");
+
+       if (have_old && !old_sha1)
+               die("BUG: have_old is true but old_sha1 is NULL");
 
+       update = add_update(transaction, refname);
        update->flags = flags;
        update->have_old = have_old;
        if (have_old) {
                assert(!is_null_sha1(old_sha1));
                hashcpy(update->old_sha1, old_sha1);
        }
+       return 0;
 }
 
 int update_ref(const char *action, const char *refname,
               const unsigned char *sha1, const unsigned char *oldval,
               int flags, enum action_on_err onerr)
 {
-       struct ref_lock *lock;
-       lock = update_ref_lock(refname, oldval, flags, NULL, onerr);
-       if (!lock)
+       struct ref_transaction *t;
+       struct strbuf err = STRBUF_INIT;
+
+       t = ref_transaction_begin(&err);
+       if (!t ||
+           ref_transaction_update(t, refname, sha1, oldval, flags,
+                                  !!oldval, &err) ||
+           ref_transaction_commit(t, action, &err)) {
+               const char *str = "update_ref failed for ref '%s': %s";
+
+               ref_transaction_free(t);
+               switch (onerr) {
+               case UPDATE_REFS_MSG_ON_ERR:
+                       error(str, refname, err.buf);
+                       break;
+               case UPDATE_REFS_DIE_ON_ERR:
+                       die(str, refname, err.buf);
+                       break;
+               case UPDATE_REFS_QUIET_ON_ERR:
+                       break;
+               }
+               strbuf_release(&err);
                return 1;
-       return update_ref_write(action, refname, sha1, lock, NULL, onerr);
+       }
+       strbuf_release(&err);
+       ref_transaction_free(t);
+       return 0;
 }
 
 static int ref_update_compare(const void *r1, const void *r2)
@@ -3520,8 +3604,13 @@ int ref_transaction_commit(struct ref_transaction *transaction,
        int n = transaction->nr;
        struct ref_update **updates = transaction->updates;
 
-       if (!n)
+       if (transaction->state != REF_TRANSACTION_OPEN)
+               die("BUG: commit called for transaction that is not open");
+
+       if (!n) {
+               transaction->state = REF_TRANSACTION_CLOSED;
                return 0;
+       }
 
        /* Allocate work space */
        delnames = xmalloc(sizeof(*delnames) * n);
@@ -3536,12 +3625,12 @@ int ref_transaction_commit(struct ref_transaction *transaction,
        for (i = 0; i < n; i++) {
                struct ref_update *update = updates[i];
 
-               update->lock = update_ref_lock(update->refname,
-                                              (update->have_old ?
-                                               update->old_sha1 : NULL),
-                                              update->flags,
-                                              &update->type,
-                                              UPDATE_REFS_QUIET_ON_ERR);
+               update->lock = lock_any_ref_for_update(update->refname,
+                                                      (update->have_old ?
+                                                       update->old_sha1 :
+                                                       NULL),
+                                                      update->flags,
+                                                      &update->type);
                if (!update->lock) {
                        if (err)
                                strbuf_addf(err, "Cannot lock the ref '%s'.",
@@ -3556,14 +3645,15 @@ int ref_transaction_commit(struct ref_transaction *transaction,
                struct ref_update *update = updates[i];
 
                if (!is_null_sha1(update->new_sha1)) {
-                       ret = update_ref_write(msg,
-                                              update->refname,
-                                              update->new_sha1,
-                                              update->lock, err,
-                                              UPDATE_REFS_QUIET_ON_ERR);
-                       update->lock = NULL; /* freed by update_ref_write */
-                       if (ret)
+                       ret = write_ref_sha1(update->lock, update->new_sha1,
+                                            msg);
+                       update->lock = NULL; /* freed by write_ref_sha1 */
+                       if (ret) {
+                               if (err)
+                                       strbuf_addf(err, "Cannot update the ref '%s'.",
+                                                   update->refname);
                                goto cleanup;
+                       }
                }
        }
 
@@ -3572,8 +3662,9 @@ int ref_transaction_commit(struct ref_transaction *transaction,
                struct ref_update *update = updates[i];
 
                if (update->lock) {
-                       delnames[delnum++] = update->lock->ref_name;
                        ret |= delete_ref_loose(update->lock, update->type);
+                       if (!(update->flags & REF_ISPRUNING))
+                               delnames[delnum++] = update->lock->ref_name;
                }
        }
 
@@ -3583,6 +3674,8 @@ int ref_transaction_commit(struct ref_transaction *transaction,
        clear_loose_ref_cache(&ref_cache);
 
 cleanup:
+       transaction->state = REF_TRANSACTION_CLOSED;
+
        for (i = 0; i < n; i++)
                if (updates[i]->lock)
                        unlock_ref(updates[i]->lock);