When the symbolic reference we want to read with refs_read_symbolic_ref
is actually not a symbolic reference, the files and the reftable
backends return different values (1 and -1 respectively). Standardize
the returned values so that 0 is success, -1 is a generic error and -2
is that the reference was actually non-symbolic.
Signed-off-by: Bence Ferdinandy <bence@xxxxxxxxxxxxxx>
---
Notes:
v13: new patch
v14: - simplified the logic in reftables backend (thanks Junio)
- update the comment in refs.h (thanks Patrick)
- rewrote comment in refs-internal.h to point to the one in refs.h
- created NOT_A_SYMREF=-2 constant
refs.h | 11 +++++++++++
refs/files-backend.c | 7 +++----
refs/refs-internal.h | 5 +++++
refs/reftable-backend.c | 8 +++++---
4 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/refs.h b/refs.h
index 108dfc93b3..22c2b45b8b 100644
--- a/refs.h
+++ b/refs.h
@@ -83,6 +83,17 @@ int refs_read_ref_full(struct ref_store *refs, const char *refname,
int refs_read_ref(struct ref_store *refs, const char *refname, struct object_id *oid);
+#define NOT_A_SYMREF -2
+
+/*
+ * Read the symbolic ref named "refname" and write its immediate referent into
+ * the provided buffer. Referent is left empty if "refname" is not a symbolic
+ * ref. It does not resolve the symbolic reference recursively in case the
+ * target is also a symbolic ref.
+ *
+ * Returns 0 on success, -2 if the "refname" is not a symbolic ref,
+ * -1 otherwise.
+ */
int refs_read_symbolic_ref(struct ref_store *ref_store, const char *refname,
struct strbuf *referent);
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 0824c0b8a9..4cc43c32f2 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -596,10 +596,9 @@ static int files_read_symbolic_ref(struct ref_store *ref_store, const char *refn
unsigned int type;
ret = read_ref_internal(ref_store, refname, &oid, referent, &type, &failure_errno, 1);
- if (ret)
- return ret;
-
- return !(type & REF_ISSYMREF);
+ if (!ret && !(type & REF_ISSYMREF))
+ return NOT_A_SYMREF;
+ return ret;
}
int parse_loose_ref_contents(const struct git_hash_algo *algop,
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 2313c830d8..1399fee61c 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -673,6 +673,11 @@ struct ref_storage_be {
ref_iterator_begin_fn *iterator_begin;
read_raw_ref_fn *read_raw_ref;
+
+ /*
+ * Please refer to `refs_read_symbolic_ref()` for the expected
+ * behaviour.
+ */
read_symbolic_ref_fn *read_symbolic_ref;
reflog_iterator_begin_fn *reflog_iterator_begin;
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index 38eb14d591..1809e3426a 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -830,10 +830,12 @@ static int reftable_be_read_symbolic_ref(struct ref_store *ref_store,
return ret;
ret = reftable_stack_read_ref(stack, refname, &ref);
- if (ret == 0 && ref.value_type == REFTABLE_REF_SYMREF)
+ if (ret)
+ ret = -1;
+ else if (ref.value_type == REFTABLE_REF_SYMREF)
strbuf_addstr(referent, ref.value.symref);
- else
- ret = -1;
+ else
+ ret = NOT_A_SYMREF;
reftable_ref_record_release(&ref);
return ret;
--
2.47.0.298.g52a96ec17b
