libctf: add ctf_ref

This allows you to bump the refcount on a ctf_file_t, so that you can
smuggle it out of iterators which open and close the ctf_file_t for you
around the loop body (like ctf_archive_iter).

You still can't use this to preserve a ctf_file_t for longer than the
lifetime of its containing entity (e.g. ctf_archive).

include/
	* ctf-api.h (ctf_ref): New.
libctf/
	* libctf.ver (ctf_ref): New.
	* ctf-open.c (ctf_ref): Implement it.

1 files changed, 11 insertions, 0 deletions

diff --git a/libctf/ctf-open.c b/libctf/ctf-open.c
index 05672f3..b7846bd 100644
--- a/libctf/ctf-open.c
+++ b/libctf/ctf-open.c
@@ -1620,6 +1620,17 @@ bad:
   return NULL;
 }
 
+/* Bump the refcount on the specified CTF container, to allow export of
+   ctf_file_t's from iterators that open and close the ctf_file_t around the
+   loop.  (This does not extend their lifetime beyond that of the ctf_archive_t
+   in which they are contained.)  */
+
+void
+ctf_ref (ctf_file_t *fp)
+{
+  fp->ctf_refcnt++;
+}
+
 /* Close the specified CTF container and free associated data structures.  Note
    that ctf_file_close() is a reference counted operation: if the specified file
    is the parent of other active containers, its reference count will be greater