Merge branch 'jk/snprintf-cleanups'
[gitweb.git] / refs / files-backend.c
index 3e0bafcaf93cf76582a52d3113b02e6f442c1a56..4d705b4037e6c1c0c1f2e277e9a5ef5bce695e61 100644 (file)
@@ -165,7 +165,8 @@ static struct ref_entry *create_dir_entry(struct files_ref_store *ref_store,
                                          const char *dirname, size_t len,
                                          int incomplete);
 static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry);
-static int files_log_ref_write(const char *refname, const unsigned char *old_sha1,
+static int files_log_ref_write(struct files_ref_store *refs,
+                              const char *refname, const unsigned char *old_sha1,
                               const unsigned char *new_sha1, const char *msg,
                               int flags, struct strbuf *err);
 
@@ -915,14 +916,10 @@ struct packed_ref_cache {
  */
 struct files_ref_store {
        struct ref_store base;
+       unsigned int store_flags;
 
-       /*
-        * The name of the submodule represented by this object, or
-        * NULL if it represents the main repository's reference
-        * store:
-        */
-       const char *submodule;
-
+       char *gitdir;
+       char *gitcommondir;
        char *packed_refs_path;
 
        struct ref_entry *loose;
@@ -980,45 +977,47 @@ static void clear_loose_ref_cache(struct files_ref_store *refs)
  * Create a new submodule ref cache and add it to the internal
  * set of caches.
  */
-static struct ref_store *files_ref_store_create(const char *submodule)
+static struct ref_store *files_ref_store_create(const char *gitdir,
+                                               unsigned int flags)
 {
        struct files_ref_store *refs = xcalloc(1, sizeof(*refs));
        struct ref_store *ref_store = (struct ref_store *)refs;
+       struct strbuf sb = STRBUF_INIT;
 
        base_ref_store_init(ref_store, &refs_be_files);
+       refs->store_flags = flags;
 
-       if (submodule) {
-               refs->submodule = xstrdup(submodule);
-               refs->packed_refs_path = git_pathdup_submodule(
-                       refs->submodule, "packed-refs");
-               return ref_store;
-       }
-
-       refs->packed_refs_path = git_pathdup("packed-refs");
+       refs->gitdir = xstrdup(gitdir);
+       get_common_dir_noenv(&sb, gitdir);
+       refs->gitcommondir = strbuf_detach(&sb, NULL);
+       strbuf_addf(&sb, "%s/packed-refs", refs->gitcommondir);
+       refs->packed_refs_path = strbuf_detach(&sb, NULL);
 
        return ref_store;
 }
 
 /*
- * Die if refs is for a submodule (i.e., not for the main repository).
- * caller is used in any necessary error messages.
+ * Die if refs is not the main ref store. caller is used in any
+ * necessary error messages.
  */
 static void files_assert_main_repository(struct files_ref_store *refs,
                                         const char *caller)
 {
-       if (refs->submodule)
-               die("BUG: %s called for a submodule", caller);
+       if (refs->store_flags & REF_STORE_MAIN)
+               return;
+
+       die("BUG: operation %s only allowed for main ref store", caller);
 }
 
 /*
  * Downcast ref_store to files_ref_store. Die if ref_store is not a
- * files_ref_store. If submodule_allowed is not true, then also die if
- * files_ref_store is for a submodule (i.e., not for the main
- * repository). caller is used in any necessary error messages.
+ * files_ref_store. required_flags is compared with ref_store's
+ * store_flags to ensure the ref_store has all required capabilities.
+ * "caller" is used in any necessary error messages.
  */
-static struct files_ref_store *files_downcast(
-               struct ref_store *ref_store, int submodule_allowed,
-               const char *caller)
+static struct files_ref_store *files_downcast(struct ref_store *ref_store,
+                                             unsigned int required_flags,
+                                             const char *caller)
 {
        struct files_ref_store *refs;
 
@@ -1028,8 +1027,9 @@ static struct files_ref_store *files_downcast(
 
        refs = (struct files_ref_store *)ref_store;
 
-       if (!submodule_allowed)
-               files_assert_main_repository(refs, caller);
+       if ((refs->store_flags & required_flags) != required_flags)
+               die("BUG: operation %s requires abilities 0x%x, but only have 0x%x",
+                   caller, required_flags, refs->store_flags);
 
        return refs;
 }
@@ -1167,6 +1167,51 @@ static const char *files_packed_refs_path(struct files_ref_store *refs)
        return refs->packed_refs_path;
 }
 
+static void files_reflog_path(struct files_ref_store *refs,
+                             struct strbuf *sb,
+                             const char *refname)
+{
+       if (!refname) {
+               /*
+                * FIXME: of course this is wrong in multi worktree
+                * setting. To be fixed real soon.
+                */
+               strbuf_addf(sb, "%s/logs", refs->gitcommondir);
+               return;
+       }
+
+       switch (ref_type(refname)) {
+       case REF_TYPE_PER_WORKTREE:
+       case REF_TYPE_PSEUDOREF:
+               strbuf_addf(sb, "%s/logs/%s", refs->gitdir, refname);
+               break;
+       case REF_TYPE_NORMAL:
+               strbuf_addf(sb, "%s/logs/%s", refs->gitcommondir, refname);
+               break;
+       default:
+               die("BUG: unknown ref type %d of ref %s",
+                   ref_type(refname), refname);
+       }
+}
+
+static void files_ref_path(struct files_ref_store *refs,
+                          struct strbuf *sb,
+                          const char *refname)
+{
+       switch (ref_type(refname)) {
+       case REF_TYPE_PER_WORKTREE:
+       case REF_TYPE_PSEUDOREF:
+               strbuf_addf(sb, "%s/%s", refs->gitdir, refname);
+               break;
+       case REF_TYPE_NORMAL:
+               strbuf_addf(sb, "%s/%s", refs->gitcommondir, refname);
+               break;
+       default:
+               die("BUG: unknown ref type %d of ref %s",
+                   ref_type(refname), refname);
+       }
+}
+
 /*
  * Get the packed_ref_cache for the specified files_ref_store,
  * creating it if necessary.
@@ -1236,19 +1281,10 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
        struct strbuf refname;
        struct strbuf path = STRBUF_INIT;
        size_t path_baselen;
-       int err = 0;
 
-       if (refs->submodule)
-               err = strbuf_git_path_submodule(&path, refs->submodule, "%s", dirname);
-       else
-               strbuf_git_path(&path, "%s", dirname);
+       files_ref_path(refs, &path, dirname);
        path_baselen = path.len;
 
-       if (err) {
-               strbuf_release(&path);
-               return;
-       }
-
        d = opendir(path.buf);
        if (!d) {
                strbuf_release(&path);
@@ -1277,7 +1313,7 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
                                         create_dir_entry(refs, refname.buf,
                                                          refname.len, 1));
                } else {
-                       if (!resolve_ref_recursively(&refs->base,
+                       if (!refs_resolve_ref_unsafe(&refs->base,
                                                     refname.buf,
                                                     RESOLVE_REF_READING,
                                                     sha1, &flag)) {
@@ -1369,7 +1405,7 @@ static int files_read_raw_ref(struct ref_store *ref_store,
                              struct strbuf *referent, unsigned int *type)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 1, "read_raw_ref");
+               files_downcast(ref_store, REF_STORE_READ, "read_raw_ref");
        struct strbuf sb_contents = STRBUF_INIT;
        struct strbuf sb_path = STRBUF_INIT;
        const char *path;
@@ -1383,10 +1419,7 @@ static int files_read_raw_ref(struct ref_store *ref_store,
        *type = 0;
        strbuf_reset(&sb_path);
 
-       if (refs->submodule)
-               strbuf_git_path_submodule(&sb_path, refs->submodule, "%s", refname);
-       else
-               strbuf_git_path(&sb_path, "%s", refname);
+       files_ref_path(refs, &sb_path, refname);
 
        path = sb_path.buf;
 
@@ -1574,7 +1607,7 @@ static int lock_raw_ref(struct files_ref_store *refs,
        *lock_p = lock = xcalloc(1, sizeof(*lock));
 
        lock->ref_name = xstrdup(refname);
-       strbuf_git_path(&ref_file, "%s", refname);
+       files_ref_path(refs, &ref_file, refname);
 
 retry:
        switch (safe_create_leading_directories(ref_file.buf)) {
@@ -1589,7 +1622,8 @@ static int lock_raw_ref(struct files_ref_store *refs,
                 * another reference such as "refs/foo". There is no
                 * reason to expect this error to be transitory.
                 */
-               if (verify_refname_available(refname, extras, skip, err)) {
+               if (refs_verify_refname_available(&refs->base, refname,
+                                                 extras, skip, err)) {
                        if (mustexist) {
                                /*
                                 * To the user the relevant error is
@@ -1789,7 +1823,9 @@ static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
 static int files_peel_ref(struct ref_store *ref_store,
                          const char *refname, unsigned char *sha1)
 {
-       struct files_ref_store *refs = files_downcast(ref_store, 0, "peel_ref");
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_READ | REF_STORE_ODB,
+                              "peel_ref");
        int flag;
        unsigned char base[20];
 
@@ -1802,7 +1838,8 @@ static int files_peel_ref(struct ref_store *ref_store,
                return 0;
        }
 
-       if (read_ref_full(refname, RESOLVE_REF_READING, base, &flag))
+       if (refs_read_ref_full(ref_store, refname,
+                              RESOLVE_REF_READING, base, &flag))
                return -1;
 
        /*
@@ -1897,8 +1934,7 @@ static struct ref_iterator *files_ref_iterator_begin(
                struct ref_store *ref_store,
                const char *prefix, unsigned int flags)
 {
-       struct files_ref_store *refs =
-               files_downcast(ref_store, 1, "ref_iterator_begin");
+       struct files_ref_store *refs;
        struct ref_dir *loose_dir, *packed_dir;
        struct ref_iterator *loose_iter, *packed_iter;
        struct files_ref_iterator *iter;
@@ -1909,6 +1945,10 @@ static struct ref_iterator *files_ref_iterator_begin(
        if (ref_paranoia)
                flags |= DO_FOR_EACH_INCLUDE_BROKEN;
 
+       refs = files_downcast(ref_store,
+                             REF_STORE_READ | (ref_paranoia ? 0 : REF_STORE_ODB),
+                             "ref_iterator_begin");
+
        iter = xcalloc(1, sizeof(*iter));
        ref_iterator = &iter->base;
        base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable);
@@ -1967,15 +2007,15 @@ static struct ref_iterator *files_ref_iterator_begin(
  * on success. On error, write an error message to err, set errno, and
  * return a negative value.
  */
-static int verify_lock(struct ref_lock *lock,
+static int verify_lock(struct ref_store *ref_store, struct ref_lock *lock,
                       const unsigned char *old_sha1, int mustexist,
                       struct strbuf *err)
 {
        assert(err);
 
-       if (read_ref_full(lock->ref_name,
-                         mustexist ? RESOLVE_REF_READING : 0,
-                         lock->old_oid.hash, NULL)) {
+       if (refs_read_ref_full(ref_store, lock->ref_name,
+                              mustexist ? RESOLVE_REF_READING : 0,
+                              lock->old_oid.hash, NULL)) {
                if (old_sha1) {
                        int save_errno = errno;
                        strbuf_addf(err, "can't verify ref '%s'", lock->ref_name);
@@ -2043,9 +2083,10 @@ static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs,
        if (flags & REF_DELETING)
                resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME;
 
-       strbuf_git_path(&ref_file, "%s", refname);
-       resolved = !!resolve_ref_unsafe(refname, resolve_flags,
-                                       lock->old_oid.hash, type);
+       files_ref_path(refs, &ref_file, refname);
+       resolved = !!refs_resolve_ref_unsafe(&refs->base,
+                                            refname, resolve_flags,
+                                            lock->old_oid.hash, type);
        if (!resolved && errno == EISDIR) {
                /*
                 * we are trying to lock foo but we used to
@@ -2062,8 +2103,9 @@ static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs,
                                            refname);
                        goto error_return;
                }
-               resolved = !!resolve_ref_unsafe(refname, resolve_flags,
-                                               lock->old_oid.hash, type);
+               resolved = !!refs_resolve_ref_unsafe(&refs->base,
+                                                    refname, resolve_flags,
+                                                    lock->old_oid.hash, type);
        }
        if (!resolved) {
                last_errno = errno;
@@ -2101,7 +2143,7 @@ static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs,
                goto error_return;
        }
 
-       if (verify_lock(lock, old_sha1, mustexist, err)) {
+       if (verify_lock(&refs->base, lock, old_sha1, mustexist, err)) {
                last_errno = errno;
                goto error_return;
        }
@@ -2313,7 +2355,9 @@ enum {
  * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or
  * REMOVE_EMPTY_PARENTS_REFLOG.
  */
-static void try_remove_empty_parents(const char *refname, unsigned int flags)
+static void try_remove_empty_parents(struct files_ref_store *refs,
+                                    const char *refname,
+                                    unsigned int flags)
 {
        struct strbuf buf = STRBUF_INIT;
        struct strbuf sb = STRBUF_INIT;
@@ -2340,12 +2384,12 @@ static void try_remove_empty_parents(const char *refname, unsigned int flags)
                strbuf_setlen(&buf, q - buf.buf);
 
                strbuf_reset(&sb);
-               strbuf_git_path(&sb, "%s", buf.buf);
+               files_ref_path(refs, &sb, buf.buf);
                if ((flags & REMOVE_EMPTY_PARENTS_REF) && rmdir(sb.buf))
                        flags &= ~REMOVE_EMPTY_PARENTS_REF;
 
                strbuf_reset(&sb);
-               strbuf_git_path(&sb, "logs/%s", buf.buf);
+               files_reflog_path(refs, &sb, buf.buf);
                if ((flags & REMOVE_EMPTY_PARENTS_REFLOG) && rmdir(sb.buf))
                        flags &= ~REMOVE_EMPTY_PARENTS_REFLOG;
        }
@@ -2354,7 +2398,7 @@ static void try_remove_empty_parents(const char *refname, unsigned int flags)
 }
 
 /* make sure nobody touched the ref, and unlink */
-static void prune_ref(struct ref_to_prune *r)
+static void prune_ref(struct files_ref_store *refs, struct ref_to_prune *r)
 {
        struct ref_transaction *transaction;
        struct strbuf err = STRBUF_INIT;
@@ -2362,7 +2406,7 @@ static void prune_ref(struct ref_to_prune *r)
        if (check_refname_format(r->name, 0))
                return;
 
-       transaction = ref_transaction_begin(&err);
+       transaction = ref_store_transaction_begin(&refs->base, &err);
        if (!transaction ||
            ref_transaction_delete(transaction, r->name, r->sha1,
                                   REF_ISPRUNING | REF_NODEREF, NULL, &err) ||
@@ -2376,10 +2420,10 @@ static void prune_ref(struct ref_to_prune *r)
        strbuf_release(&err);
 }
 
-static void prune_refs(struct ref_to_prune *r)
+static void prune_refs(struct files_ref_store *refs, struct ref_to_prune *r)
 {
        while (r) {
-               prune_ref(r);
+               prune_ref(refs, r);
                r = r->next;
        }
 }
@@ -2387,7 +2431,8 @@ static void prune_refs(struct ref_to_prune *r)
 static int files_pack_refs(struct ref_store *ref_store, unsigned int flags)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "pack_refs");
+               files_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB,
+                              "pack_refs");
        struct pack_refs_cb_data cbdata;
 
        memset(&cbdata, 0, sizeof(cbdata));
@@ -2402,7 +2447,7 @@ static int files_pack_refs(struct ref_store *ref_store, unsigned int flags)
        if (commit_packed_refs(refs))
                die_errno("unable to overwrite old ref-pack file");
 
-       prune_refs(cbdata.ref_to_prune);
+       prune_refs(refs, cbdata.ref_to_prune);
        return 0;
 }
 
@@ -2466,7 +2511,7 @@ static int files_delete_refs(struct ref_store *ref_store,
                             struct string_list *refnames, unsigned int flags)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "delete_refs");
+               files_downcast(ref_store, REF_STORE_WRITE, "delete_refs");
        struct strbuf err = STRBUF_INIT;
        int i, result = 0;
 
@@ -2494,7 +2539,7 @@ static int files_delete_refs(struct ref_store *ref_store,
        for (i = 0; i < refnames->nr; i++) {
                const char *refname = refnames->items[i].string;
 
-               if (delete_ref(NULL, refname, NULL, flags))
+               if (refs_delete_ref(&refs->base, NULL, refname, NULL, flags))
                        result |= error(_("could not remove reference %s"), refname);
        }
 
@@ -2538,15 +2583,15 @@ static int rename_tmp_log_callback(const char *path, void *cb_data)
        }
 }
 
-static int rename_tmp_log(const char *newrefname)
+static int rename_tmp_log(struct files_ref_store *refs, const char *newrefname)
 {
        struct strbuf path = STRBUF_INIT;
        struct strbuf tmp = STRBUF_INIT;
        struct rename_cb cb;
        int ret;
 
-       strbuf_git_path(&path, "logs/%s", newrefname);
-       strbuf_git_path(&tmp, "logs/%s", TMP_RENAMED_LOG);
+       files_reflog_path(refs, &path, newrefname);
+       files_reflog_path(refs, &tmp, TMP_RENAMED_LOG);
        cb.tmp_renamed_log = tmp.buf;
        ret = raceproof_create_file(path.buf, rename_tmp_log_callback, &cb);
        if (ret) {
@@ -2570,7 +2615,7 @@ static int files_verify_refname_available(struct ref_store *ref_store,
                                          struct strbuf *err)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 1, "verify_refname_available");
+               files_downcast(ref_store, REF_STORE_READ, "verify_refname_available");
        struct ref_dir *packed_refs = get_packed_refs(refs);
        struct ref_dir *loose_refs = get_loose_refs(refs);
 
@@ -2595,7 +2640,7 @@ static int files_rename_ref(struct ref_store *ref_store,
                            const char *logmsg)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "rename_ref");
+               files_downcast(ref_store, REF_STORE_WRITE, "rename_ref");
        unsigned char sha1[20], orig_sha1[20];
        int flag = 0, logmoved = 0;
        struct ref_lock *lock;
@@ -2606,9 +2651,9 @@ static int files_rename_ref(struct ref_store *ref_store,
        int log, ret;
        struct strbuf err = STRBUF_INIT;
 
-       strbuf_git_path(&sb_oldref, "logs/%s", oldrefname);
-       strbuf_git_path(&sb_newref, "logs/%s", newrefname);
-       strbuf_git_path(&tmp_renamed_log, "logs/%s", TMP_RENAMED_LOG);
+       files_reflog_path(refs, &sb_oldref, oldrefname);
+       files_reflog_path(refs, &sb_newref, newrefname);
+       files_reflog_path(refs, &tmp_renamed_log, TMP_RENAMED_LOG);
 
        log = !lstat(sb_oldref.buf, &loginfo);
        if (log && S_ISLNK(loginfo.st_mode)) {
@@ -2616,7 +2661,8 @@ static int files_rename_ref(struct ref_store *ref_store,
                goto out;
        }
 
-       if (!resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+       if (!refs_resolve_ref_unsafe(&refs->base, oldrefname,
+                                    RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
                                orig_sha1, &flag)) {
                ret = error("refname %s not found", oldrefname);
                goto out;
@@ -2627,7 +2673,7 @@ static int files_rename_ref(struct ref_store *ref_store,
                            oldrefname);
                goto out;
        }
-       if (!rename_ref_available(oldrefname, newrefname)) {
+       if (!refs_rename_ref_available(&refs->base, oldrefname, newrefname)) {
                ret = 1;
                goto out;
        }
@@ -2638,7 +2684,8 @@ static int files_rename_ref(struct ref_store *ref_store,
                goto out;
        }
 
-       if (delete_ref(logmsg, oldrefname, orig_sha1, REF_NODEREF)) {
+       if (refs_delete_ref(&refs->base, logmsg, oldrefname,
+                           orig_sha1, REF_NODEREF)) {
                error("unable to delete old %s", oldrefname);
                goto rollback;
        }
@@ -2650,14 +2697,16 @@ static int files_rename_ref(struct ref_store *ref_store,
         * the safety anyway; we want to delete the reference whatever
         * its current value.
         */
-       if (!read_ref_full(newrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
-                          sha1, NULL) &&
-           delete_ref(NULL, newrefname, NULL, REF_NODEREF)) {
+       if (!refs_read_ref_full(&refs->base, newrefname,
+                               RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+                               sha1, NULL) &&
+           refs_delete_ref(&refs->base, NULL, newrefname,
+                           NULL, REF_NODEREF)) {
                if (errno == EISDIR) {
                        struct strbuf path = STRBUF_INIT;
                        int result;
 
-                       strbuf_git_path(&path, "%s", newrefname);
+                       files_ref_path(refs, &path, newrefname);
                        result = remove_empty_directories(&path);
                        strbuf_release(&path);
 
@@ -2671,7 +2720,7 @@ static int files_rename_ref(struct ref_store *ref_store,
                }
        }
 
-       if (log && rename_tmp_log(newrefname))
+       if (log && rename_tmp_log(refs, newrefname))
                goto rollback;
 
        logmoved = log;
@@ -2786,10 +2835,15 @@ static int open_or_create_logfile(const char *path, void *cb)
  * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and
  * return -1.
  */
-static int log_ref_setup(const char *refname, int force_create,
+static int log_ref_setup(struct files_ref_store *refs,
+                        const char *refname, int force_create,
                         int *logfd, struct strbuf *err)
 {
-       char *logfile = git_pathdup("logs/%s", refname);
+       struct strbuf logfile_sb = STRBUF_INIT;
+       char *logfile;
+
+       files_reflog_path(refs, &logfile_sb, refname);
+       logfile = strbuf_detach(&logfile_sb, NULL);
 
        if (force_create || should_autocreate_reflog(refname)) {
                if (raceproof_create_file(logfile, open_or_create_logfile, logfd)) {
@@ -2839,12 +2893,11 @@ static int files_create_reflog(struct ref_store *ref_store,
                               const char *refname, int force_create,
                               struct strbuf *err)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_WRITE, "create_reflog");
        int fd;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "create_reflog");
-
-       if (log_ref_setup(refname, force_create, &fd, err))
+       if (log_ref_setup(refs, refname, force_create, &fd, err))
                return -1;
 
        if (fd >= 0)
@@ -2879,7 +2932,8 @@ static int log_ref_write_fd(int fd, const unsigned char *old_sha1,
        return 0;
 }
 
-static int files_log_ref_write(const char *refname, const unsigned char *old_sha1,
+static int files_log_ref_write(struct files_ref_store *refs,
+                              const char *refname, const unsigned char *old_sha1,
                               const unsigned char *new_sha1, const char *msg,
                               int flags, struct strbuf *err)
 {
@@ -2888,7 +2942,8 @@ static int files_log_ref_write(const char *refname, const unsigned char *old_sha
        if (log_all_ref_updates == LOG_REFS_UNSET)
                log_all_ref_updates = is_bare_repository() ? LOG_REFS_NONE : LOG_REFS_NORMAL;
 
-       result = log_ref_setup(refname, flags & REF_FORCE_CREATE_REFLOG,
+       result = log_ref_setup(refs, refname,
+                              flags & REF_FORCE_CREATE_REFLOG,
                               &logfd, err);
 
        if (result)
@@ -2902,7 +2957,7 @@ static int files_log_ref_write(const char *refname, const unsigned char *old_sha
                struct strbuf sb = STRBUF_INIT;
                int save_errno = errno;
 
-               strbuf_git_path(&sb, "logs/%s", refname);
+               files_reflog_path(refs, &sb, refname);
                strbuf_addf(err, "unable to append to '%s': %s",
                            sb.buf, strerror(save_errno));
                strbuf_release(&sb);
@@ -2913,7 +2968,7 @@ static int files_log_ref_write(const char *refname, const unsigned char *old_sha
                struct strbuf sb = STRBUF_INIT;
                int save_errno = errno;
 
-               strbuf_git_path(&sb, "logs/%s", refname);
+               files_reflog_path(refs, &sb, refname);
                strbuf_addf(err, "unable to append to '%s': %s",
                            sb.buf, strerror(save_errno));
                strbuf_release(&sb);
@@ -2974,7 +3029,8 @@ static int commit_ref_update(struct files_ref_store *refs,
        files_assert_main_repository(refs, "commit_ref_update");
 
        clear_loose_ref_cache(refs);
-       if (files_log_ref_write(lock->ref_name, lock->old_oid.hash, sha1,
+       if (files_log_ref_write(refs, lock->ref_name,
+                               lock->old_oid.hash, sha1,
                                logmsg, 0, err)) {
                char *old_msg = strbuf_detach(err, NULL);
                strbuf_addf(err, "cannot update the ref '%s': %s",
@@ -3001,13 +3057,15 @@ static int commit_ref_update(struct files_ref_store *refs,
                int head_flag;
                const char *head_ref;
 
-               head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
-                                             head_sha1, &head_flag);
+               head_ref = refs_resolve_ref_unsafe(&refs->base, "HEAD",
+                                                  RESOLVE_REF_READING,
+                                                  head_sha1, &head_flag);
                if (head_ref && (head_flag & REF_ISSYMREF) &&
                    !strcmp(head_ref, lock->ref_name)) {
                        struct strbuf log_err = STRBUF_INIT;
-                       if (files_log_ref_write("HEAD", lock->old_oid.hash, sha1,
-                                         logmsg, 0, &log_err)) {
+                       if (files_log_ref_write(refs, "HEAD",
+                                               lock->old_oid.hash, sha1,
+                                               logmsg, 0, &log_err)) {
                                error("%s", log_err.buf);
                                strbuf_release(&log_err);
                        }
@@ -3039,24 +3097,28 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target)
        return ret;
 }
 
-static void update_symref_reflog(struct ref_lock *lock, const char *refname,
+static void update_symref_reflog(struct files_ref_store *refs,
+                                struct ref_lock *lock, const char *refname,
                                 const char *target, const char *logmsg)
 {
        struct strbuf err = STRBUF_INIT;
        unsigned char new_sha1[20];
-       if (logmsg && !read_ref(target, new_sha1) &&
-           files_log_ref_write(refname, lock->old_oid.hash, new_sha1,
-                               logmsg, 0, &err)) {
+       if (logmsg &&
+           !refs_read_ref_full(&refs->base, target,
+                               RESOLVE_REF_READING, new_sha1, NULL) &&
+           files_log_ref_write(refs, refname, lock->old_oid.hash,
+                               new_sha1, logmsg, 0, &err)) {
                error("%s", err.buf);
                strbuf_release(&err);
        }
 }
 
-static int create_symref_locked(struct ref_lock *lock, const char *refname,
+static int create_symref_locked(struct files_ref_store *refs,
+                               struct ref_lock *lock, const char *refname,
                                const char *target, const char *logmsg)
 {
        if (prefer_symlink_refs && !create_ref_symlink(lock, target)) {
-               update_symref_reflog(lock, refname, target, logmsg);
+               update_symref_reflog(refs, lock, refname, target, logmsg);
                return 0;
        }
 
@@ -3064,7 +3126,7 @@ static int create_symref_locked(struct ref_lock *lock, const char *refname,
                return error("unable to fdopen %s: %s",
                             lock->lk->tempfile.filename.buf, strerror(errno));
 
-       update_symref_reflog(lock, refname, target, logmsg);
+       update_symref_reflog(refs, lock, refname, target, logmsg);
 
        /* no error check; commit_ref will check ferror */
        fprintf(lock->lk->tempfile.fp, "ref: %s\n", target);
@@ -3079,7 +3141,7 @@ static int files_create_symref(struct ref_store *ref_store,
                               const char *logmsg)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "create_symref");
+               files_downcast(ref_store, REF_STORE_WRITE, "create_symref");
        struct strbuf err = STRBUF_INIT;
        struct ref_lock *lock;
        int ret;
@@ -3093,13 +3155,22 @@ static int files_create_symref(struct ref_store *ref_store,
                return -1;
        }
 
-       ret = create_symref_locked(lock, refname, target, logmsg);
+       ret = create_symref_locked(refs, lock, refname, target, logmsg);
        unlock_ref(lock);
        return ret;
 }
 
 int set_worktree_head_symref(const char *gitdir, const char *target, const char *logmsg)
 {
+       /*
+        * FIXME: this obviously will not work well for future refs
+        * backends. This function needs to die.
+        */
+       struct files_ref_store *refs =
+               files_downcast(get_main_ref_store(),
+                              REF_STORE_WRITE,
+                              "set_head_symref");
+
        static struct lock_file head_lock;
        struct ref_lock *lock;
        struct strbuf head_path = STRBUF_INIT;
@@ -3126,7 +3197,7 @@ int set_worktree_head_symref(const char *gitdir, const char *target, const char
        lock->lk = &head_lock;
        lock->ref_name = xstrdup(head_rel);
 
-       ret = create_symref_locked(lock, head_rel, target, logmsg);
+       ret = create_symref_locked(refs, lock, head_rel, target, logmsg);
 
        unlock_ref(lock); /* will free lock */
        strbuf_release(&head_path);
@@ -3136,14 +3207,13 @@ int set_worktree_head_symref(const char *gitdir, const char *target, const char
 static int files_reflog_exists(struct ref_store *ref_store,
                               const char *refname)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_READ, "reflog_exists");
        struct strbuf sb = STRBUF_INIT;
        struct stat st;
        int ret;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "reflog_exists");
-
-       strbuf_git_path(&sb, "logs/%s", refname);
+       files_reflog_path(refs, &sb, refname);
        ret = !lstat(sb.buf, &st) && S_ISREG(st.st_mode);
        strbuf_release(&sb);
        return ret;
@@ -3152,13 +3222,12 @@ static int files_reflog_exists(struct ref_store *ref_store,
 static int files_delete_reflog(struct ref_store *ref_store,
                               const char *refname)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_WRITE, "delete_reflog");
        struct strbuf sb = STRBUF_INIT;
        int ret;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "delete_reflog");
-
-       strbuf_git_path(&sb, "logs/%s", refname);
+       files_reflog_path(refs, &sb, refname);
        ret = remove_path(sb.buf);
        strbuf_release(&sb);
        return ret;
@@ -3209,15 +3278,15 @@ static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store,
                                             each_reflog_ent_fn fn,
                                             void *cb_data)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_READ,
+                              "for_each_reflog_ent_reverse");
        struct strbuf sb = STRBUF_INIT;
        FILE *logfp;
        long pos;
        int ret = 0, at_tail = 1;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "for_each_reflog_ent_reverse");
-
-       strbuf_git_path(&sb, "logs/%s", refname);
+       files_reflog_path(refs, &sb, refname);
        logfp = fopen(sb.buf, "r");
        strbuf_release(&sb);
        if (!logfp)
@@ -3318,14 +3387,14 @@ static int files_for_each_reflog_ent(struct ref_store *ref_store,
                                     const char *refname,
                                     each_reflog_ent_fn fn, void *cb_data)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_READ,
+                              "for_each_reflog_ent");
        FILE *logfp;
        struct strbuf sb = STRBUF_INIT;
        int ret = 0;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "for_each_reflog_ent");
-
-       strbuf_git_path(&sb, "logs/%s", refname);
+       files_reflog_path(refs, &sb, refname);
        logfp = fopen(sb.buf, "r");
        strbuf_release(&sb);
        if (!logfp)
@@ -3341,6 +3410,7 @@ static int files_for_each_reflog_ent(struct ref_store *ref_store,
 struct files_reflog_iterator {
        struct ref_iterator base;
 
+       struct ref_store *ref_store;
        struct dir_iterator *dir_iterator;
        struct object_id oid;
 };
@@ -3362,8 +3432,9 @@ static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator)
                if (ends_with(diter->basename, ".lock"))
                        continue;
 
-               if (read_ref_full(diter->relative_path, 0,
-                                 iter->oid.hash, &flags)) {
+               if (refs_read_ref_full(iter->ref_store,
+                                      diter->relative_path, 0,
+                                      iter->oid.hash, &flags)) {
                        error("bad ref for %s", diter->path.buf);
                        continue;
                }
@@ -3407,16 +3478,17 @@ static struct ref_iterator_vtable files_reflog_iterator_vtable = {
 
 static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_READ,
+                              "reflog_iterator_begin");
        struct files_reflog_iterator *iter = xcalloc(1, sizeof(*iter));
        struct ref_iterator *ref_iterator = &iter->base;
        struct strbuf sb = STRBUF_INIT;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "reflog_iterator_begin");
-
        base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable);
-       strbuf_git_path(&sb, "logs");
+       files_reflog_path(refs, &sb, NULL);
        iter->dir_iterator = dir_iterator_begin(sb.buf);
+       iter->ref_store = ref_store;
        strbuf_release(&sb);
        return ref_iterator;
 }
@@ -3656,8 +3728,9 @@ static int lock_ref_for_update(struct files_ref_store *refs,
                         * the transaction, so we have to read it here
                         * to record and possibly check old_sha1:
                         */
-                       if (read_ref_full(referent.buf, 0,
-                                         lock->old_oid.hash, NULL)) {
+                       if (refs_read_ref_full(&refs->base,
+                                              referent.buf, 0,
+                                              lock->old_oid.hash, NULL)) {
                                if (update->flags & REF_HAVE_OLD) {
                                        strbuf_addf(err, "cannot lock ref '%s': "
                                                    "error reading reference",
@@ -3747,7 +3820,8 @@ static int files_transaction_commit(struct ref_store *ref_store,
                                    struct strbuf *err)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "ref_transaction_commit");
+               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;
@@ -3810,8 +3884,9 @@ static int files_transaction_commit(struct ref_store *ref_store,
         * head_ref within the transaction, then split_head_update()
         * arranges for the reflog of HEAD to be updated, too.
         */
-       head_ref = resolve_refdup("HEAD", RESOLVE_REF_NO_RECURSE,
-                                 head_oid.hash, &head_type);
+       head_ref = refs_resolve_refdup(ref_store, "HEAD",
+                                      RESOLVE_REF_NO_RECURSE,
+                                      head_oid.hash, &head_type);
 
        if (head_ref && !(head_type & REF_ISSYMREF)) {
                free(head_ref);
@@ -3840,7 +3915,8 @@ static int files_transaction_commit(struct ref_store *ref_store,
 
                if (update->flags & REF_NEEDS_COMMIT ||
                    update->flags & REF_LOG_ONLY) {
-                       if (files_log_ref_write(lock->ref_name,
+                       if (files_log_ref_write(refs,
+                                               lock->ref_name,
                                                lock->old_oid.hash,
                                                update->new_sha1,
                                                update->msg, update->flags,
@@ -3878,7 +3954,7 @@ static int files_transaction_commit(struct ref_store *ref_store,
                            update->type & REF_ISSYMREF) {
                                /* It is a loose reference. */
                                strbuf_reset(&sb);
-                               strbuf_git_path(&sb, "%s", lock->ref_name);
+                               files_ref_path(refs, &sb, lock->ref_name);
                                if (unlink_or_msg(sb.buf, err)) {
                                        ret = TRANSACTION_GENERIC_ERROR;
                                        goto cleanup;
@@ -3900,9 +3976,9 @@ static int files_transaction_commit(struct ref_store *ref_store,
        /* Delete the reflogs of any references that were deleted: */
        for_each_string_list_item(ref_to_delete, &refs_to_delete) {
                strbuf_reset(&sb);
-               strbuf_git_path(&sb, "logs/%s", ref_to_delete->string);
+               files_reflog_path(refs, &sb, ref_to_delete->string);
                if (!unlink_or_warn(sb.buf))
-                       try_remove_empty_parents(ref_to_delete->string,
+                       try_remove_empty_parents(refs, ref_to_delete->string,
                                                 REMOVE_EMPTY_PARENTS_REFLOG);
        }
 
@@ -3926,7 +4002,7 @@ static int files_transaction_commit(struct ref_store *ref_store,
                         * can only work because we have already
                         * removed the lockfile.)
                         */
-                       try_remove_empty_parents(update->refname,
+                       try_remove_empty_parents(refs, update->refname,
                                                 REMOVE_EMPTY_PARENTS_REF);
                }
        }
@@ -3951,7 +4027,8 @@ static int files_initial_transaction_commit(struct ref_store *ref_store,
                                            struct strbuf *err)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "initial_ref_transaction_commit");
+               files_downcast(ref_store, REF_STORE_WRITE,
+                              "initial_ref_transaction_commit");
        int ret = 0, i;
        struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
 
@@ -3982,7 +4059,8 @@ static int files_initial_transaction_commit(struct ref_store *ref_store,
         * so here we really only check that none of the references
         * that we are creating already exists.
         */
-       if (for_each_rawref(ref_present, &affected_refnames))
+       if (refs_for_each_rawref(&refs->base, ref_present,
+                                &affected_refnames))
                die("BUG: initial ref transaction called with existing refs");
 
        for (i = 0; i < transaction->nr; i++) {
@@ -3991,9 +4069,9 @@ static int files_initial_transaction_commit(struct ref_store *ref_store,
                if ((update->flags & REF_HAVE_OLD) &&
                    !is_null_sha1(update->old_sha1))
                        die("BUG: initial ref transaction with old_sha1 set");
-               if (verify_refname_available(update->refname,
-                                            &affected_refnames, NULL,
-                                            err)) {
+               if (refs_verify_refname_available(&refs->base, update->refname,
+                                                 &affected_refnames, NULL,
+                                                 err)) {
                        ret = TRANSACTION_NAME_CONFLICT;
                        goto cleanup;
                }
@@ -4073,10 +4151,11 @@ static int files_reflog_expire(struct ref_store *ref_store,
                               void *policy_cb_data)
 {
        struct files_ref_store *refs =
-               files_downcast(ref_store, 0, "reflog_expire");
+               files_downcast(ref_store, REF_STORE_WRITE, "reflog_expire");
        static struct lock_file reflog_lock;
        struct expire_reflog_cb cb;
        struct ref_lock *lock;
+       struct strbuf log_file_sb = STRBUF_INIT;
        char *log_file;
        int status = 0;
        int type;
@@ -4100,12 +4179,13 @@ static int files_reflog_expire(struct ref_store *ref_store,
                strbuf_release(&err);
                return -1;
        }
-       if (!reflog_exists(refname)) {
+       if (!refs_reflog_exists(ref_store, refname)) {
                unlock_ref(lock);
                return 0;
        }
 
-       log_file = git_pathdup("logs/%s", refname);
+       files_reflog_path(refs, &log_file_sb, refname);
+       log_file = strbuf_detach(&log_file_sb, NULL);
        if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
                /*
                 * Even though holding $GIT_DIR/logs/$reflog.lock has
@@ -4130,7 +4210,7 @@ static int files_reflog_expire(struct ref_store *ref_store,
        }
 
        (*prepare_fn)(refname, sha1, cb.policy_cb);
-       for_each_reflog_ent(refname, expire_reflog_ent, &cb);
+       refs_for_each_reflog_ent(ref_store, refname, expire_reflog_ent, &cb);
        (*cleanup_fn)(cb.policy_cb);
 
        if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
@@ -4176,19 +4256,18 @@ static int files_reflog_expire(struct ref_store *ref_store,
 
 static int files_init_db(struct ref_store *ref_store, struct strbuf *err)
 {
+       struct files_ref_store *refs =
+               files_downcast(ref_store, REF_STORE_WRITE, "init_db");
        struct strbuf sb = STRBUF_INIT;
 
-       /* Check validity (but we don't need the result): */
-       files_downcast(ref_store, 0, "init_db");
-
        /*
         * Create .git/refs/{heads,tags}
         */
-       strbuf_git_path(&sb, "refs/heads");
+       files_ref_path(refs, &sb, "refs/heads");
        safe_create_dir(sb.buf, 1);
 
        strbuf_reset(&sb);
-       strbuf_git_path(&sb, "refs/tags");
+       files_ref_path(refs, &sb, "refs/tags");
        safe_create_dir(sb.buf, 1);
 
        strbuf_release(&sb);