ffi: carrays able to reference objects.

The idea here is that carrays can have a pointer to some area
that is owned by another object. So that the area doesn't
disappear when the other object becomes garbage, a carray
which does this maintains a pointer to that other object.

* ffi.c (ffi_carray_get): Pass new parameter to make_carray.
(struct carray): New member, ref.
(carray_mark_op): Mark new ref member.
(make_carray): New parameter: the object which is stored in
the structure as ref.
(carray_dup): Null out the ref member. When a carray
is duplicated, it owns its own buffer, and henceforth mustn't
prevent the original object from being reclaimed.
(carray_own): Don't allow a carray to claim ownership
of the pointer if it references another object; we have
no protocol to inform that other object.

* ffi.h (make_carray): Declaration updated.

1 files changed, 1 insertions, 1 deletions

diff --git a/ffi.h b/ffi.h
index 0d82f29d..e9b188f2 100644
--- a/ffi.h
+++ b/ffi.h
@@ -63,7 +63,7 @@ val ffi_put(val obj, val type);
 val ffi_in(val srcbuf, val obj, val type, val copy_p);
 val ffi_get(val srcbuf, val type);
 val ffi_out(val dstbuf, val obj, val type, val copy_p);
-val make_carray(val type, mem_t *data, cnum nelem);
+val make_carray(val type, mem_t *data, cnum nelem, val ref);
 val carray_set_length(val carray, val nelem);
 val carray_dup(val carray);
 val carray_own(val carray);