static int is_special_ref(const char *refname)
{
/*
- * Special references get written and read directly via the filesystem
- * by the subsystems that create them. Thus, they must not go through
- * the reference backend but must instead be read directly. It is
- * arguable whether this behaviour is sensible, or whether it's simply
- * a leaky abstraction enabled by us only having a single reference
- * backend implementation. But at least for a subset of references it
- * indeed does make sense to treat them specially:
+ * Special references are refs that have different semantics compared
+ * to "normal" refs. These refs can thus not be stored in the ref
+ * backend, but must always be accessed via the filesystem. The
+ * following refs are special:
*
* - FETCH_HEAD may contain multiple object IDs, and each one of them
* carries additional metadata like where it came from.
* - MERGE_HEAD may contain multiple object IDs when merging multiple
* heads.
*
- * There are some exceptions that you might expect to see on this list
- * but which are handled exclusively via the reference backend:
- *
- * - BISECT_EXPECTED_REV
- *
- * - CHERRY_PICK_HEAD
- *
- * - HEAD
- *
- * - ORIG_HEAD
- *
- * - "rebase-apply/" and "rebase-merge/" contain all of the state for
- * rebases, including some reference-like files. These are
- * exclusively read and written via the filesystem and never go
- * through the refdb.
- *
- * Writing or deleting references must consistently go either through
- * the filesystem (special refs) or through the reference backend
- * (normal ones).
+ * Reading, writing or deleting references must consistently go either
+ * through the filesystem (special refs) or through the reference
+ * backend (normal ones).
*/
static const char * const special_refs[] = {
"FETCH_HEAD",