external/cffi.darcs/examples/translator-test.lisp

   1 ;;;; -*- Mode: lisp; indent-tabs-mode: nil -*-
   2 ;;;
   3 ;;; translator-test.lisp --- Testing type translators.
   4 ;;;
   5 ;;; Copyright (C) 2005-2006, James Bielman  <jamesjb@jamesjb.com>
   6 ;;;
   7 ;;; Permission is hereby granted, free of charge, to any person
   8 ;;; obtaining a copy of this software and associated documentation
   9 ;;; files (the "Software"), to deal in the Software without
  10 ;;; restriction, including without limitation the rights to use, copy,
  11 ;;; modify, merge, publish, distribute, sublicense, and/or sell copies
  12 ;;; of the Software, and to permit persons to whom the Software is
  13 ;;; furnished to do so, subject to the following conditions:
  14 ;;;
  15 ;;; The above copyright notice and this permission notice shall be
  16 ;;; included in all copies or substantial portions of the Software.
  17 ;;;
  18 ;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19 ;;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 ;;; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21 ;;; NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  22 ;;; HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  23 ;;; WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24 ;;; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  25 ;;; DEALINGS IN THE SOFTWARE.
  26 ;;;
  27
  28 (defpackage #:cffi-translator-test
  29   (:use #:common-lisp #:cffi #:cffi-utils))
  30
  31 (in-package #:cffi-translator-test)
  32
  33 ;;;# Verbose Pointer Translator
  34 ;;;
  35 ;;; This is a silly type translator that doesn't actually do any
  36 ;;; translating, but it prints out a debug message when the pointer is
  37 ;;; converted to/from its foreign representation.
  38
  39 (define-foreign-type verbose-pointer-type ()
  40   ()
  41   (:actual-type :pointer))
  42
  43 (defmethod translate-to-foreign (value (type verbose-pointer-type))
  44   (format *debug-io* "~&;; to foreign: VERBOSE-POINTER: ~S~%" value)
  45   value)
  46
  47 (defmethod translate-from-foreign (value (type verbose-pointer-type))
  48   (format *debug-io* "~&;; from foreign: VERBOSE-POINTER: ~S~%" value)
  49   value)
  50
  51 ;;;# Verbose String Translator
  52 ;;;
  53 ;;; A VERBOSE-STRING extends VERBOSE-POINTER and converts Lisp strings
  54 ;;; C strings.  If things are working properly, both type translators
  55 ;;; should be called when converting a Lisp string to/from a C string.
  56 ;;;
  57 ;;; The translators should be called most-specific-first when
  58 ;;; translating to C, and most-specific-last when translating from C.
  59
  60 (define-foreign-type verbose-string-type (verbose-pointer-type)
  61   ()
  62   (:simple-parser verbose-string))
  63
  64 (defmethod translate-to-foreign ((s string) (type verbose-string-type))
  65   (let ((value (foreign-string-alloc s)))
  66     (format *debug-io* "~&;; to foreign: VERBOSE-STRING: ~S -> ~S~%" s value)
  67     (values (call-next-method value type) t)))
  68
  69 (defmethod translate-to-foreign (value (type verbose-string-type))
  70   (if (pointerp value)
  71       (progn
  72         (format *debug-io* "~&;; to foreign: VERBOSE-STRING: ~S -> ~:*~S~%" value)
  73         (values (call-next-method) nil))
  74       (error "Cannot convert ~S to a foreign string: it is not a Lisp ~
  75               string or pointer." value)))
  76
  77 (defmethod translate-from-foreign (ptr (type verbose-string-type))
  78   (let ((value (foreign-string-to-lisp (call-next-method))))
  79     (format *debug-io* "~&;; from foreign: VERBOSE-STRING: ~S -> ~S~%" ptr value)
  80     value))
  81
  82 (defmethod free-translated-object (ptr (type verbose-string-type) free-p)
  83   (when free-p
  84     (format *debug-io* "~&;; freeing VERBOSE-STRING: ~S~%" ptr)
  85     (foreign-string-free ptr)))
  86
  87 (defun test-verbose-string ()
  88   (foreign-funcall "getenv" verbose-string "SHELL" verbose-string))