[PATCH v4 04/21] refs: add do_for_each_per_worktree_ref

[David Turner <dturner@twopensource.com>]

Alternate refs backends might still use files to store per-worktree
refs.  So the files backend's ref-loading infrastructure should be
available to those backends, just for use on per-worktree refs.  Add
do_for_each_per_worktree_ref, which iterates over per-worktree refs.

Signed-off-by: David Turner <dturner@twopensource.com>
---
 refs/files-backend.c | 15 ++++++++++++---
 refs/refs-internal.h | 10 ++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/refs/files-backend.c b/refs/files-backend.c
index 0772a02..3d678ad 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -518,9 +518,6 @@ static void sort_ref_dir(struct ref_dir *dir)
 	dir->sorted = dir->nr = i;
 }
 
-/* Include broken references in a do_for_each_ref*() iteration: */
-#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
-
 /*
  * Return true iff the reference described by entry can be resolved to
  * an object in the database.  Emit a warning if the referred-to
@@ -568,6 +565,10 @@ static int do_one_ref(struct ref_entry *entry, void *cb_data)
 	struct ref_entry *old_current_ref;
 	int retval;
 
+	if (data->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&
+	    ref_type(entry->name) != REF_TYPE_PER_WORKTREE)
+		return 0;
+
 	if (!starts_with(entry->name, data->base))
 		return 0;
 
@@ -1756,6 +1757,14 @@ static int do_for_each_ref(struct ref_cache *refs, const char *base,
 	return do_for_each_entry(refs, base, do_one_ref, &data);
 }
 
+int do_for_each_per_worktree_ref(const char *submodule, const char *base,
+				 each_ref_fn fn, int trim, int flags,
+				 void *cb_data)
+{
+	return do_for_each_ref(get_ref_cache(submodule), base, fn, trim,
+			       flags | DO_FOR_EACH_PER_WORKTREE_ONLY, cb_data);
+}
+
 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
 {
 	struct object_id oid;
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 4a1d215..cb949c5 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -57,6 +57,16 @@
  */
 int refname_is_safe(const char *refname);
 
+/* Include broken references in a do_for_each_ref*() iteration */
+#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
+
+/* Only include per-worktree refs in a do_for_each_ref*() iteration */
+#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
+
+int do_for_each_per_worktree_ref(const char *submodule, const char *base,
+				 each_ref_fn fn, int trim, int flags,
+				 void *cb_data);
+
 enum peel_status {
 	/* object was peeled successfully: */
 	PEEL_PEELED = 0,
-- 
2.4.2.749.g730654d-twtrsrc