* libguile/foreign.h:
* libguile/foreign.c (scm_foreign_set_finalizer_x): New function, for a
limited form of finalization (like `free').
(scm_alignof, scm_sizeof, parse_ffi_type, fill_ffi_type): For the
purposes of make-foreign-function, treat '* (the asterisk symbol) as a
pointer.
* module/system/foreign.scm: Export foreign-set-finalizer!.
* libguile/Makefile.am (AM_CPPFLAGS): Move LIBFFI_CFLAGS here (from
AM_CFLAGS), allowing snarfing to work.
* libguile/foreign.h (scm_make_foreign_function): New public function.
* libguile/foreign.c: Flesh out an implementation of foreign functions.
(scm_take_foreign_pointer): Bugfix for the case in which we have a
finalizer.
* module/system/foreign.scm: Export `make-foreign-function'.
* libguile/foreign.h:
* libguile/foreign.c (scm_foreign_ref, scm_foreign_set_x): Remove all
bits about offsets and aliasing; bytevectors are much better at that.
(scm_foreign_to_bytevector, scm_bytevector_to_foreign): New functions
for getting at the bytes of a memory region.
* module/system/foreign.scm (foreign->bytevector, bytevector->foreign):
Export these.
* libguile/foreign.h:
* libguile/init.c: Change so that init just registers an extension,
later called by foreign.scm.
* libguile/foreign.c (scm_init_foreign): Define constants for the
various foreign types.
* module/Makefile.am:
* module/system/foreign.scm: New module, for the foreign function
interface.
