ffi: implementing FFI callback closures.

* ffi.c (closure_s, ffi_closure_s): New symbol vars.
(struct txr_ffi_closure): New type.
(ffi_closure_struct, ffi_closure_struct_checked,
ffi_closure_print_op, ffi_closure_destroy_op,
ffi_closure_mark_op): New static functions.
(ffi_closure_ops): New static struct.
(ffi_closure_put): New static function.
(ffi_type_compile): Handle closure_s to support closure type
specifier.
(ffi_closure_dispatch): New static function.
(ffi_make_closure, ffi_closure_get_fptr): New function.
(ffi_init): Initialize closure_ and ffi_closure_s.
Register ffi-make-closure intrinsic.

* ffi.c (closure_s, ffi_closure_s, ffi_make_closure,
ffi_closure_get_fptr): Likewise.

1 files changed, 5 insertions, 1 deletions

diff --git a/ffi.h b/ffi.h
index 12d9705a..2845ccc4 100644
--- a/ffi.h
+++ b/ffi.h
@@ -47,9 +47,13 @@ extern val buf_d_s;
 
 extern val ptr_in_s, ptr_out_s, ptr_in_d_s, ptr_out_d_s, ptr_s;
 
-extern val ffi_type_s, ffi_call_desc_s;
+extern val closure_s;
+
+extern val ffi_type_s, ffi_call_desc_s, ffi_closure_s;
 
 val ffi_type_compile(val syntax);
 val ffi_make_call_desc(val ntotal, val nfixed, val rettype, val argtypes);
+val ffi_make_closure(val fun, val call_desc);
+mem_t *ffi_closure_get_fptr(val closure);
 val ffi_call_wrap(val ffi_call_desc, val fptr, val args);
 void ffi_init(void);