lispworks-read-foreign.lisp

(defmacro read-foreign (foreign-type buffer index)
  (let ((size (fli:size-of foreign-type)))
    `(let ((index ,index))
       (fli:with-dynamic-foreign-objects ((value ,foreign-type))
         (fli:with-coerced-pointer (bytes :type '(:unsigned :char)) value
           (dotimes (byte-index ,size)
             (let ((endian-byte-index #+LITTLE-ENDIAN byte-index
                                      #-LITTLE-ENDIAN (- (1- limit) byte-index)))
               (setf (fli:dereference bytes :index endian-byte-index)
                     (aref ,buffer index)))
             (incf index))
           (values (fli:dereference value) index)
           )))))

(defmacro write-foreign (value foreign-type buffer index)
  (let ((size (fli:size-of foreign-type)))
    `(fli:with-dynamic-foreign-objects ((value ,foreign-type :initial-element ,value))
       (fli:with-coerced-pointer (bytes :type '(:unsigned :char)) value
         (dotimes (byte-index ,size)
           (let ((endian-byte-index #+LITTLE-ENDIAN byte-index
                                    #-LITTLE-ENDIAN (- (1- limit) byte-index)))
             (setf (aref ,buffer ,index)
                   (fli:dereference bytes :index endian-byte-index)))
           (incf ,index))
         ,index
         ))))