libctf: add ctf_type_kind_forwarded

This is just like ctf_type_kind, except that forwards get the
type of the thing being pointed to rather than CTF_K_FORWARD.

include/
	* ctf-api.h (ctf_type_kind_forwarded): New.
libctf/
	* ctf-types.c (ctf_type_kind_forwarded): New.

1 files changed, 20 insertions, 0 deletions

diff --git a/libctf/ctf-types.c b/libctf/ctf-types.c
index ce3890c..d8f848c 100644
--- a/libctf/ctf-types.c
+++ b/libctf/ctf-types.c
@@ -677,6 +677,26 @@ ctf_type_kind (ctf_file_t *fp, ctf_id_t type)
   return kind;
 }
 
+/* Return the kind of this type, except, for forwards, return the kind of thing
+   this is a forward to.  */
+int
+ctf_type_kind_forwarded (ctf_file_t *fp, ctf_id_t type)
+{
+  int kind;
+  const ctf_type_t *tp;
+
+  if ((kind = ctf_type_kind (fp, type)) < 0)
+    return -1;			/* errno is set for us.  */
+
+  if (kind != CTF_K_FORWARD)
+    return kind;
+
+  if ((tp = ctf_lookup_by_id (&fp, type)) == NULL)
+    return -1;			/* errno is set for us.  */
+
+  return tp->ctt_type;
+}
+
 /* If the type is one that directly references another type (such as POINTER),
    then return the ID of the type to which it refers.  */