macros.lisp

;;; -*- Mode: LISP; Syntax: Common-lisp; Package: XLIB; Base: 10; Lowercase: Yes -*-

;;;
;;;                      TEXAS INSTRUMENTS INCORPORATED
;;;                               P.O. BOX 2909
;;;                            AUSTIN, TEXAS 78769
;;;
;;; Copyright (C) 1987 Texas Instruments Incorporated.
;;;
;;; Permission is granted to any individual or institution to use, copy, modify,
;;; and distribute this software, provided that this complete copyright and
;;; permission notice is maintained, intact, in all copies and supporting
;;; documentation.
;;;
;;; Texas Instruments Incorporated provides this software "as is" without
;;; express or implied warranty.
;;;

;;; CLX basically implements a very low overhead remote procedure call
;;; to the server.  This file contains macros which generate the code
;;; for both the client AND the server, given a specification of the
;;; interface. This was done to eliminate errors that may occur because
;;; the client and server code get/put bytes in different places, and
;;; it makes it easier to extend the protocol.

;;; This is built on top of BUFFER

(in-package :xlib)

(defmacro type-check (value type)
  value type
  (when +type-check?+
    `(unless (type? ,value ,type)
       (x-type-error ,value ,type))))

;;; This variable is used by the required-arg macro just to satisfy compilers.
(defvar *required-arg-dummy*)

;;; An error signalling macro use to specify that keyword arguments are required.
(defmacro required-arg (name)
  `(progn (x-error 'missing-parameter :parameter ',name)
          *required-arg-dummy*))

(defmacro lround (index)
  ;; Round up to the next 32 bit boundary
  `(the array-index (logand (index+ ,index 3) -4)))

(defmacro wround (index)
  ;; Round up to the next 16 bit boundary
  `(the array-index (logand (index+ ,index 1) -2)))

;;
;; Data-type accessor functions
;;
;;   These functions translate between lisp data-types and the byte,
;;   half-word or word that gets transmitted across the client/server
;;   connection

(defun index-increment (type)
  ;; Given a type, return its field width in bytes
  (let* ((name (if (consp type) (car type) type))
         (increment (get name 'byte-width :not-found)))
    (when (eq increment :not-found)
      ;; Check for TYPE in a different package
      (when (not (eq (symbol-package name) *xlib-package*))
        (setq name (xintern name))
        (setq increment (get name 'byte-width :not-found)))
      (when (eq increment :not-found)
        (error "~s isn't a known field accessor" name)))
    increment))

(eval-when (:compile-toplevel :load-toplevel :execute)
  (defun getify (name)
    (xintern name '-get))

  (defun putify (name &optional predicate-p)
    (xintern name '-put (if predicate-p '-predicating "")))

;;; Use &body so zmacs indents properly
  (defmacro define-accessor (name (width) &body get-put-macros)
    ;; The first body form defines the get macro
    ;; The second body form defines the put macro
    ;; The third body form is optional, and defines a put macro that does
    ;; type checking and does a put when ok, else NIL when the type is incorrect.
    ;; If no third body form is present, then these macros assume that
    ;; (AND (TYPEP ,thing 'type) (PUT-type ,thing)) can be generated.
    ;; these predicating puts are used by the OR accessor.
    (declare (arglist name (width) get-macro put-macro &optional predicating-put-macro))
    (when (cdddr get-put-macros)
      (error "Too many parameters to define-accessor: ~s" (cdddr get-put-macros)))
    (let ((get-macro (or (first get-put-macros) (error "No GET macro form for ~s" name)))
          (put-macro (or (second get-put-macros) (error "No PUT macro form for ~s" name))))
      `(within-definition (,name define-accessor)
         (setf (get ',name 'byte-width) ,(and width (floor width 8)))
         (defmacro ,(getify name) ,(car get-macro)
           ,@(cdr get-macro))
         (defmacro ,(putify name) ,(car put-macro)
           ,@(cdr put-macro))
         ,@(let ((predicating-put (third get-put-macros)))
             (when predicating-put
               `((setf (get ',name 'predicating-put) t)
                 (defmacro ,(putify name t) ,(car predicating-put)
                   ,@(cdr predicating-put))))))))
  ) ;; End eval-when

(define-accessor card32 (32)
  ((index) `(read-card32 ,index))
  ((index thing) `(write-card32 ,index ,thing)))

(define-accessor card29 (32)
  ((index) `(read-card29 ,index))
  ((index thing) `(write-card29 ,index ,thing)))

(define-accessor card16 (16)
  ((index) `(read-card16 ,index))
  ((index thing) `(write-card16 ,index ,thing)))

(define-accessor card8 (8)
  ((index) `(read-card8 ,index))
  ((index thing) `(write-card8 ,index ,thing)))

(define-accessor integer (32)
  ((index) `(read-int32 ,index))
  ((index thing) `(write-int32 ,index ,thing)))

(define-accessor int16 (16)
  ((index) `(read-int16 ,index))
  ((index thing) `(write-int16 ,index ,thing)))

(define-accessor rgb-val (16)
  ;; Used for color's
  ((index) `(card16->rgb-val (read-card16 ,index)))
  ((index thing) `(write-card16 ,index (rgb-val->card16 ,thing))))

(define-accessor angle (16)
  ;; Used for drawing arcs
  ((index) `(int16->radians (read-int16 ,index)))
  ((index thing) `(write-int16 ,index (radians->int16 ,thing))))

(define-accessor bit (0)
  ;; Like BOOLEAN, but tests bits
  ;; only used by declare-event (:enter-notify :leave-notify)
  ((index bit)
   `(logbitp ,bit (read-card8 ,index)))
  ((index thing bit)
   (if (zerop bit)
       `(write-card8 ,index (if ,thing 1 0))
       `(write-card8 ,index (dpb (if ,thing 1 0) (byte 1 ,bit) (read-card8 ,index))))))

(define-accessor boolean (8)
  ((index)
   `(plusp (read-card8 ,index)))
  ((index thing) `(write-card8 ,index (if ,thing 1 0))))

(define-accessor drawable (32)
  ((index &optional (buffer '%buffer))
   `(lookup-drawable ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (drawable-id ,thing))))

(define-accessor window (32)
  ((index &optional (buffer '%buffer))
   `(lookup-window ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (window-id ,thing))))

(define-accessor pixmap (32)
  ((index &optional (buffer '%buffer))
   `(lookup-pixmap ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (pixmap-id ,thing))))

(define-accessor gcontext (32)
  ((index &optional (buffer '%buffer))
   `(lookup-gcontext ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (gcontext-id ,thing))))

(define-accessor cursor (32)
  ((index &optional (buffer '%buffer))
   `(lookup-cursor ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (cursor-id ,thing))))

(define-accessor colormap (32)
  ((index &optional (buffer '%buffer))
   `(lookup-colormap ,buffer (read-card29 ,index)))
  ((index thing) `(write-card29 ,index (colormap-id ,thing))))

(define-accessor font (32)
  ((index &optional (buffer '%buffer))
   `(lookup-font ,buffer (read-card29 ,index)))
  ;; The FONT-ID accessor may make a OpenFont request.  Since we don't support recursive
  ;; with-buffer-request, issue a compile time error, rather than barf at run-time.
  ((index thing)
   (declare (ignore index thing))
   (error "FONT-ID must be called OUTSIDE with-buffer-request.  Use RESOURCE-ID instead.")))

;; Needed to get and put xatom's in events
(define-accessor keyword (32)
  ((index &optional (buffer '%buffer))
   `(atom-name ,buffer (read-card29 ,index)))
  ((index thing &key (buffer '%buffer))
   `(write-card29 ,index (or (atom-id ,thing ,buffer)
                             (error "CLX implementation error in KEYWORD-PUT")))))

(define-accessor resource-id (32)
  ((index) `(read-card29 ,index))
  ((index thing) `(write-card29 ,index ,thing)))

(define-accessor resource-id-or-nil (32)
  ((index) (let ((id (gensym)))
             `(let ((,id (read-card29 ,index)))
                (and (plusp ,id) ,id))))
  ((index thing) `(write-card29 ,index (or ,thing 0))))

(defmacro char-info-get (index)
  `(make-char-info
    :left-bearing (int16-get ,index)
    :right-bearing (int16-get ,(+ index 2))
    :width         (int16-get ,(+ index 4))
    :ascent        (int16-get ,(+ index 6))
    :descent       (int16-get ,(+ index 8))
    :attributes   (card16-get ,(+ index 10))))

(defun generate-member-case (thing keywords mismatch-error-p)
  `(case ,thing
     ,@(loop :for i :from 0
             :for keyword :in keywords
             :collect `(,keyword ,i))
     ,@(when mismatch-error-p
         `((t (x-type-error ,thing '(member ,@keywords)))))))

(defun generate-member-lookup (thing keywords mismatch-error-p)
  (let ((lookup `(position ,thing
                           #+lispm ',keywords ;; Lispm's prefer lists
                           #-lispm (the simple-vector ',(apply #'vector keywords))
                           :test #'eq)))
    (if mismatch-error-p
        `(or ,lookup
             (x-type-error ,thing '(member ,@keywords)))
        lookup)))

(defun generate-member-to-integer (thing keywords mismatch-error-p)
  (if (< (length keywords) 8)
      (generate-member-case thing keywords mismatch-error-p)
      (generate-member-lookup thing keywords mismatch-error-p)))

(define-accessor member8 (8)
  ((index &rest keywords)
   (let ((value (gensym)))
     `(let ((,value (read-card8 ,index)))
        (declare (type (integer 0 (,(length keywords))) ,value))
        (type-check ,value '(integer 0 (,(length keywords))))
        (svref ',(apply #'vector keywords) ,value))))
  ((index thing &rest keywords)
   `(write-card8 ,index ,(generate-member-to-integer thing keywords t)))
  ((index thing &rest keywords)
   (let ((value (gensym)))
     `(let ((,value ,(generate-member-to-integer thing keywords t)))
        (and ,value (write-card8 ,index ,value))))))

(define-accessor member16 (16)
  ((index &rest keywords)
   (let ((value (gensym)))
     `(let ((,value (read-card16 ,index)))
        (declare (type (integer 0 (,(length keywords))) ,value))
        (type-check ,value '(integer 0 (,(length keywords))))
        (svref ',(apply #'vector keywords) ,value))))
  ((index thing &rest keywords)
   `(write-card16 ,index ,(generate-member-to-integer thing keywords t)))
  ((index thing &rest keywords)
   (let ((value (gensym)))
     `(let ((,value ,(generate-member-to-integer thing keywords nil)))
        (and ,value (write-card16 ,index ,value))))))

(define-accessor member (32)
  ((index &rest keywords)
   (let ((value (gensym)))
     `(let ((,value (read-card29 ,index)))
        (declare (type (integer 0 (,(length keywords))) ,value))
        (type-check ,value '(integer 0 (,(length keywords))))
        (svref ',(apply #'vector keywords) ,value))))
  ((index thing &rest keywords)
   `(write-card29 ,index ,(generate-member-to-integer thing keywords t)))
  ((index thing &rest keywords)
   (let ((value (gensym)))
     `(let ((,value ,(generate-member-to-integer thing keywords nil)))
        (and ,value (write-card29 ,index ,value))))))

(deftype member-vector (vector) `(member ,@(coerce (symbol-value vector) 'list)))

(define-accessor member-vector (32)
  ((index membership-vector)
   `(member-get ,index ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member-put ,index ,thing ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member-put ,index ,thing ,@(coerce (eval membership-vector) 'list))))

(define-accessor member16-vector (16)
  ((index membership-vector)
   `(member16-get ,index ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member16-put ,index ,thing ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member16-put ,index ,thing ,@(coerce (eval membership-vector) 'list))))

(define-accessor member8-vector (8)
  ((index membership-vector)
   `(member8-get ,index ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member8-put ,index ,thing ,@(coerce (eval membership-vector) 'list)))
  ((index thing membership-vector)
   `(member8-put ,index ,thing ,@(coerce (eval membership-vector) 'list))))

(define-accessor boole-constant (32)
  ;; this isn't member-vector because we need eql instead of eq
  ((index)
   (let ((value (gensym)))
     `(let ((,value (read-card29 ,index)))
        (declare (type (integer 0 (,(length +boole-vector+))) ,value))
        (type-check ,value '(integer 0 (,(length +boole-vector+))))
        (svref +boole-vector+ ,value))))
  ((index thing)
   `(write-card29 ,index (position ,thing (the simple-vector +boole-vector+))))
  ((index thing)
   (let ((value (gensym)))
     `(let ((,value (position ,thing (the simple-vector +boole-vector+))))
        (and ,value (write-card29 ,index ,value))))))

(define-accessor null (32)
  ((index) `(if (zerop (read-card32 ,index)) nil (read-card32 ,index)))
  ((index value) (declare (ignore value)) `(write-card32 ,index 0)))

(define-accessor pad8 (8)
  ((index) (declare (ignore index)) nil)
  ((index value) (declare (ignore index value))  nil))

(define-accessor pad16 (16)
  ((index) (declare (ignore index)) nil)
  ((index value) (declare (ignore index value)) nil))

(define-accessor pad32 (32)
  ((index) (declare (ignore index)) nil)
  ((index value) (declare (ignore index value)) nil))

(define-accessor bit-vector256 (256)
  ;; used for key-maps
  ;; REAL-INDEX parameter provided so the default index can be over-ridden.
  ;; This is needed for the :keymap-notify event where the keymap overlaps
  ;; the window id.
  ((index &optional (real-index index) data)
   `(read-bitvector256 buffer-bbuf ,real-index ,data))
  ((index map &optional (real-index index) (buffer '%buffer))
   `(write-bitvector256 ,buffer (index+ buffer-boffset ,real-index) ,map)))

(define-accessor string (nil)
  ((length index &key reply-buffer)
   `(read-sequence-char
     ,(or reply-buffer '%reply-buffer) 'string ,length nil nil 0 ,index))
  ((index string &key buffer (start 0) end header-length appending)
   (unless buffer (setq buffer '%buffer))
   (unless header-length (setq header-length (lround index)))
   (let* ((real-end (if appending (or end `(length ,string)) (gensym)))
          (form `(write-sequence-char ,buffer (index+ buffer-boffset ,header-length)
                                      ,string ,start ,real-end)))
     (if appending
         form
         `(let ((,real-end ,(or end `(length ,string))))
            (write-card16 2 (index-ceiling (index+ (index- ,real-end ,start) ,header-length) 4))
            ,form)))))

(define-accessor sequence (nil)
  ((&key length (format 'card32) result-type transform reply-buffer data index start)
   `(,(ecase format
        (card8 'read-sequence-card8)
        (int8 'read-sequence-int8)
        (card16 'read-sequence-card16)
        (int16 'read-sequence-int16)
        (card32 'read-sequence-card32)
        (int32 'read-sequence-int32))
      ,(or reply-buffer '%reply-buffer)
      ,result-type ,length ,transform ,data
      ,@(when (or start index) `(,(or start 0)))
      ,@(when index `(,index))))
  ((index data &key (format 'card32) (start 0) end transform buffer appending)
   (unless buffer (setq buffer '%buffer))
   (let* ((real-end (if appending (or end `(length ,data)) (gensym)))
          (writer (xintern 'write-sequence- format))
          (form `(,writer ,buffer (index+ buffer-boffset ,(lround index))
                          ,data ,start ,real-end ,transform)))
     (flet ((maker (size)
              (if appending
                  form
                  (let ((idx `(index- ,real-end ,start)))
                    (unless (= size 1)
                      (setq idx `(index-ceiling ,idx ,size)))
                    `(let ((,real-end ,(or end `(length ,data))))
                       (write-card16 2 (index+ ,idx ,(index-ceiling index 4)))
                       ,form)))))
       (ecase format
         ((card8 int8)
          (maker 4))
         ((card16 int16 char2b)
          (maker 2))
         ((card32 int32)
          (maker 1)))))))

(defmacro client-message-event-get-sequence ()
  '(let* ((format (read-card8 1))
          (sequence (make-array (ceiling 160 format)
                                :element-type `(unsigned-byte ,format))))
    (declare (type (member 8 16 32) format))
    (do ((i 12)
         (j 0 (index1+ j)))
        ((>= i 32))
      (case format
        (8 (setf (aref sequence j) (read-card8 i))
           (index-incf i))
        (16 (setf (aref sequence j) (read-card16 i))
            (index-incf i 2))
        (32 (setf (aref sequence j) (read-card32 i))
            (index-incf i 4))))
    sequence))

(defmacro client-message-event-put-sequence (format sequence)
  `(ecase ,format
     (8  (sequence-put 12 ,sequence
                       :format card8
                       :end (min (length ,sequence) 20)
                       :appending t))
     (16 (sequence-put 12 ,sequence
                       :format card16
                       :end (min (length ,sequence) 10)
                       :appending t))
     (32 (sequence-put 12 ,sequence
                       :format card32
                       :end (min (length ,sequence) 5)
                       :appending t))))

;; Used only in declare-event
(define-accessor client-message-sequence (160)
  ((index format) (declare (ignore index format)) `(client-message-event-get-sequence))
  ((index value format) (declare (ignore index))
   `(client-message-event-put-sequence ,format ,value)))


;;;
;;; Compound accessors
;;;    Accessors that take other accessors as parameters
;;;
(define-accessor code (0)
  ((index) (declare (ignore index)) '(read-card8 0))
  ((index value) (declare (ignore index)) `(write-card8 0 ,value))
  ((index value) (declare (ignore index)) `(write-card8 0 ,value)))

(define-accessor length (0)
  ((index) (declare (ignore index)) '(read-card16 2))
  ((index value) (declare (ignore index)) `(write-card16 2 ,value))
  ((index value) (declare (ignore index)) `(write-card16 2 ,value)))

(deftype data () 'card8)

(define-accessor data (0)
  ;; Put data in byte 1 of the reqeust
  ((index &optional stuff) (declare (ignore index))
   (if stuff
       (if (consp stuff)
           `(,(getify (car stuff)) 1 ,@(cdr stuff))
           `(,(getify stuff) 1))
       `(read-card8 1)))
  ((index thing &optional stuff)
   (if stuff
       (if (consp stuff)
           `(macrolet ((write-card32 (index value) index value))
              (write-card8 1 (,(putify (car stuff)) ,index ,thing ,@(cdr stuff))))
           `(,(putify stuff) 1 ,thing))
       `(write-card8 1 ,thing)))
  ((index thing &optional stuff)
   (if stuff
       `(and (type? ,thing ',stuff)
             ,(if (consp stuff)
                  `(macrolet ((write-card32 (index value) index value))
                     (write-card8 1 (,(putify (car stuff)) ,index ,thing ,@(cdr stuff))))
                  `(,(putify stuff) 1 ,thing)))
       `(and (type? ,thing 'card8) (write-card8 1 ,thing)))))

;;
;; the OR type
;;
(define-accessor or (32)
  ;; Select from among two types (NULL/MEMBER and something else).
  ((index &rest type-list)
   ;; OR-GET accessor accepts only two types. The first one must enum (either
   ;; null or a member specifier). Otherwise if the first type didn't match we
   ;; could have a condition signalled by a type-check or by other assertions
   ;; generated by the compiler (deduced from declarations). -- jd 2018-11-07
   (unless (= (length type-list) 2)
     (x-type-error type-list '(or enum t) "an alternative of enum and other type."))
   (let ((value (gensym)))
     (flet ((static-check (item &aux args)
              (when (consp item)
                (setf args (cdr item)
                      item (car item)))
              (ecase item
                (null   `((zerop ,value) nil))
                (member `((<= 0 ,value ,(length args))
                          (svref ',(apply #'vector args) ,value)))))
            (dynamic-check (item &aux args)
              (when (consp item)
                (setf args (cdr item)
                      item (car item)))
              `(,(getify item) ,index ,@args)))
       `(let ((,value (read-card32 ,index)))
          (macrolet ((read-card32 (index) index ',value)
                     (read-card29 (index) index ',value))
            (if ,@(static-check (first type-list))
                ,(dynamic-check (second type-list))))))))
  ((index value &rest type-list)
   (do ((types type-list (cdr types))
        (result))
       ((endp types)
        `(cond ,@(nreverse result)
               ,@(when +type-check?+
                   `((t (x-type-error ,value '(or ,@type-list)))))))
     (let* ((type (car types))
            (type-name type)
            (args nil))
       (when (consp type)
         (setq args (cdr type)
               type-name (car type)))
       (push
        `(,@(cond ((get type-name 'predicating-put) nil)
                  ((or +type-check?+ (cdr types)) `((type? ,value ',type)))
                  (t '(t)))
            (,(putify type-name (get type-name 'predicating-put)) ,index ,value ,@args))
        result)))))

;;
;; the MASK type...
;;     is used to specify a subset of a collection of "optional" arguments.
;;     A mask type consists of a 32 bit mask word followed by a word for each one-bit
;;     in the mask.  The MASK type is ALWAYS the LAST item in a request.
;;
(setf (get 'mask 'byte-width) nil)

(defun mask-get (index type-values body-function)
  (declare (type function body-function)
           (dynamic-extent body-function))
  ;; This is a function, because it must return more than one form (called by get-put-items)
  ;; Functions that use this must have a binding for %MASK
  (let* ((bit 0)
         (result
          (mapcar
           #'(lambda (form)
               (if (atom form)
                   form ;; Hack to allow BODY-FUNCTION to return keyword/value pairs
                   (prog1
                       `(when (logbitp ,bit %mask)
                          ;; Execute form when bit is set
                          ,form)
                     (incf bit))))
           (get-put-items
            (+ index 4) type-values nil
            #'(lambda (type index item args)
                (declare (ignore index))
                (funcall body-function type '(* (incf %index) 4) item args))))))
    ;; First form must load %MASK
    `(,@(when (atom (car result))
          (list (pop result)))
        (progn (setq %mask (read-card32 ,index))
               (setq %index ,(ceiling index 4))
               ,(car result))
        ,@(cdr result))))

;; MASK-PUT

(defun mask-put (index type-values body-function)
  (declare (type function body-function)
           (dynamic-extent body-function))
  ;; The MASK type writes a 32 bit mask with 1 bits for each non-nil value in TYPE-VALUES
  ;; A 32 bit value follows for each non-nil value.
  `((let ((%mask 0)
          (%index ,index))
      ,@(let ((bit 1))
          (get-put-items
           index type-values t
           #'(lambda (type index item args)
               (declare (ignore index))
               (if (or (symbolp item) (constantp item))
                   `((unless (null ,item)
                       (setq %mask (logior %mask ,(shiftf bit (ash bit 1))))
                       ,@(funcall body-function type
                                  `(index-incf %index 4) item args)))
                   `((let ((.item. ,item))
                       (unless (null .item.)
                         (setq %mask (logior %mask ,(shiftf bit (ash bit 1))))
                         ,@(funcall body-function type
                                    `(index-incf %index 4) '.item. args))))))))
      (write-card32 ,index %mask)
      (write-card16 2 (index-ceiling (index-incf %index 4) 4))
      (incf (buffer-boffset %buffer) %index))))

(define-accessor progn (nil)
  ;; Catch-all for inserting random code
  ;; Note that code using this is then responsible for setting the request length
  ((index statement) (declare (ignore index)) statement)
  ((index statement) (declare (ignore index)) statement))


                                        ;
                                        ; Wrapper macros, for use around the above
                                        ;

;;; type-check was here, and has been moved up

(defmacro check-put (index value type &rest args &environment env)
  (let* ((var (if (or (symbolp value) (constantp value)) value '.value.))
         (body
          (if (or (null (macroexpand `(type-check ,var ',type) env))
                  (member type '(or progn pad8 pad16))
                  (constantp value))
              `(,(putify type) ,index ,var ,@args)
              ;; Do type checking
              (if (get type 'predicating-put)
                  `(or (,(putify type t) ,index ,var ,@args)
                       (x-type-error ,var ',(if args `(,type ,@args) type)))
                  `(if (type? ,var ',type)
                       (,(putify type) ,index ,var ,@args)
                       (x-type-error ,var ',(if args `(,type ,@args) type)))))))
    (if (eq var value)
        body
        `(let ((,var ,value))
           ,body))))

(defun get-put-items (index type-args putp &optional body-function)
  (declare (type (or null function) body-function)
           (dynamic-extent body-function))
  ;; Given a lists of the form (type item item ... item)
  ;; Calls body-function with four arguments, a function name,
  ;; index, item name, and optional arguments.
  ;; The results are appended together and retured.
  (unless body-function
    (setq body-function
          #'(lambda (type index item args)
              `((check-put ,index ,item ,type ,@args)))))
  (do* ((items type-args (cdr items))
        (type (caar items) (caar items))
        (args nil nil)
        (result nil)
        (sizes nil))
       ((endp items) (values result index sizes))
    (when (consp type)
      (setq args (cdr type)
            type (car type)))
    (cond ((member type '(return buffer)))
          ((eq type 'mask) ;; Hack to enable mask-get/put to return multiple values
           (setq result
                 (append result (if putp
                                    (mask-put index (cdar items) body-function)
                                    (mask-get index (cdar items) body-function)))
                 index nil))
          (t (do* ((item (cdar items) (cdr item))
                   (increment (index-increment type)))
                  ((endp item))
               (when (constantp index)
                 (case increment		;Round up index when needed
                   (2 (setq index (wround index)))
                   (4 (setq index (lround index)))))
               (setq result
                     (append result (funcall body-function type index (car item) args)))
               (when (constantp index)
                 ;; Variable length requests have null length increment.
                 ;; Variable length requests set the request size
                 ;; & maintain buffer pointers
                 (if (null increment)
                     (setq index nil)
                     (progn
                       (incf index increment)
                       (when (and increment (zerop increment)) (setq increment 1))
                       (pushnew (* increment 8) sizes)))))))))

(defmacro with-buffer-request-internal
    ((buffer opcode &key length sizes &allow-other-keys)
     &body type-args)
  (multiple-value-bind (code index item-sizes)
      (get-put-items 4 type-args t)
    (let ((length (if length `(index+ ,length +requestsize+) '+requestsize+))
          (sizes (remove-duplicates (append '(8 16) item-sizes sizes))))
      `(with-buffer-output (,buffer :length ,length :sizes ,sizes)
         (setf (buffer-last-request ,buffer) buffer-boffset)
         (write-card8 0 ,opcode)           ;; Stick in the opcode
         ,@code
         ,@(when index
             (setq index (lround index))
             `((write-card16 2 ,(ceiling index 4))
               (setf (buffer-boffset ,buffer) (index+ buffer-boffset ,index))))
         (buffer-new-request-number ,buffer)))))

(defmacro with-buffer-request
    ((buffer opcode &rest options &key inline gc-force &allow-other-keys)
     &body type-args &environment env)
  (if (and (null inline) (macroexpand '(use-closures) env))
      `(flet ((.request-body. (.display.)
                (declare (type display .display.))
                (with-buffer-request-internal (.display. ,opcode ,@options)
                  ,@type-args)))
         (declare (dynamic-extent #'.request-body.))
         (,(if (eq (car (macroexpand '(with-buffer (buffer)) env)) 'progn)
               'with-buffer-request-function-nolock
               'with-buffer-request-function)
           ,buffer ,gc-force #'.request-body.))
      `(let ((.display. ,buffer))
         (declare (type display .display.))
         (with-buffer (.display.)
           ,@(when gc-force `((force-gcontext-changes-internal ,gc-force)))
           (multiple-value-prog1
               (without-aborts
                 (with-buffer-request-internal (.display. ,opcode ,@options)
                   ,@type-args))
             (display-invoke-after-function .display.))))))

(defmacro with-buffer-request-and-reply
    ((buffer opcode reply-size &key sizes multiple-reply inline)
                                 type-args &body reply-forms &environment env)
  (declare (indentation 0 4 1 4 2 1))
  (let* ((inner-reply-body
          `(with-buffer-input (.reply-buffer. :display .display.
                                              ,@(and sizes (list :sizes sizes)))
             nil ,@reply-forms))
         (reply-body
          (if (or (not (symbolp reply-size)) (constantp reply-size))
              inner-reply-body
              `(let ((,reply-size (reply-data-size (the reply-buffer .reply-buffer.))))
                 (declare (type array-index ,reply-size))
                 ,inner-reply-body))))
    (if (and (null inline) (macroexpand '(use-closures) env))
        `(flet ((.request-body. (.display.)
                  (declare (type display .display.))
                  (with-buffer-request-internal (.display. ,opcode)
                    ,@type-args))
                (.reply-body. (.display. .reply-buffer.)
                  (declare (type display .display.)
                           (type reply-buffer .reply-buffer.))
                  (progn .display. .reply-buffer. nil)
                  ,reply-body))
           (declare (dynamic-extent #'.request-body. #'.reply-body.))
           (with-buffer-request-and-reply-function
               ,buffer ,multiple-reply #'.request-body. #'.reply-body.))
        `(let ((.display. ,buffer)
               (.pending-command. nil)
               (.reply-buffer. nil))
           (declare (type display .display.)
                    (type (or null pending-command) .pending-command.)
                    (type (or null reply-buffer) .reply-buffer.))
           (unwind-protect
                (progn
                  (with-buffer (.display.)
                    (setq .pending-command. (start-pending-command .display.))
                    (without-aborts
                      (with-buffer-request-internal (.display. ,opcode)
                        ,@type-args))
                    (buffer-force-output .display.)
                    (display-invoke-after-function .display.))
                  ,@(if multiple-reply
                        `((loop
                             (setq .reply-buffer. (read-reply .display. .pending-command.))
                             (when ,reply-body (return nil))
                             (deallocate-reply-buffer (shiftf .reply-buffer. nil))))
                        `((setq .reply-buffer. (read-reply .display. .pending-command.))
                          ,reply-body)))
             (when .reply-buffer.
               (deallocate-reply-buffer .reply-buffer.))
             (when .pending-command.
               (stop-pending-command .display. .pending-command.)))))))

(defmacro compare-request ((index) &body body)
  `(macrolet ((write-card32 (index item) `(= ,item (read-card32 ,index)))
              (write-int32 (index item) `(= ,item (read-int32 ,index)))
              (write-card29 (index item) `(= ,item (read-card29 ,index)))
              (write-int29 (index item) `(= ,item (read-int29 ,index)))
              (write-card16 (index item) `(= ,item (read-card16 ,index)))
              (write-int16 (index item) `(= ,item (read-int16 ,index)))
              (write-card8 (index item) `(= ,item (read-card8 ,index)))
              (write-int8 (index item) `(= ,item (read-int8 ,index))))
     (macrolet ((type-check (value type) value type nil))
       (and ,@(get-put-items index body t)))))

(defmacro put-items ((index) &body body)
  `(progn ,@(get-put-items index body t)))

(defmacro decode-type (type value)
  ;; Given an integer and type, return the value
  (let ((args nil))
    (when (consp type)
      (setq args (cdr type)
            type (car type)))
    `(macrolet ((read-card29 (value) value)
                (read-card32 (value) value)
                (read-int32 (value) `(card32->int32 ,value))
                (read-card16 (value) value)
                (read-int16 (value) `(card16->int16 ,value))
                (read-card8 (value) value)
                (read-int8 (value) `(int8->card8 ,value)))
       (,(getify type) ,value ,@args))))

(defmacro encode-type (type value)
  ;; Given a value and type, return an integer
  ;; When check-p, do type checking on value
  (let ((args nil))
    (when (consp type)
      (setq args (cdr type)
            type (car type)))
    `(macrolet ((write-card29 (index value) index value)
                (write-card32 (index value) index value)
                (write-int32 (index value) index `(int32->card32 ,value))
                (write-card16 (index value) index value)
                (write-int16 (index value) index `(int16->card16 ,value))
                (write-card8 (index value) index value)
                (write-int8 (index value) index `(int8->card8 ,value)))
       (check-put 0 ,value ,type ,@args))))

(defmacro set-decode-type (type accessor value)
  `(setf ,accessor (encode-type ,type ,value)))
(defsetf decode-type set-decode-type)


;;;
;;; Request codes
;;;

(defconstant +x-createwindow+                  1)
(defconstant +x-changewindowattributes+        2)
(defconstant +x-getwindowattributes+           3)
(defconstant +x-destroywindow+                 4)
(defconstant +x-destroysubwindows+             5)
(defconstant +x-changesaveset+                 6)
(defconstant +x-reparentwindow+                7)
(defconstant +x-mapwindow+                     8)
(defconstant +x-mapsubwindows+                 9)
(defconstant +x-unmapwindow+                  10)
(defconstant +x-unmapsubwindows+              11)
(defconstant +x-configurewindow+              12)
(defconstant +x-circulatewindow+              13)
(defconstant +x-getgeometry+                  14)
(defconstant +x-querytree+                    15)
(defconstant +x-internatom+                   16)
(defconstant +x-getatomname+                  17)
(defconstant +x-changeproperty+               18)
(defconstant +x-deleteproperty+               19)
(defconstant +x-getproperty+                  20)
(defconstant +x-listproperties+               21)
(defconstant +x-setselectionowner+            22)
(defconstant +x-getselectionowner+            23)
(defconstant +x-convertselection+             24)
(defconstant +x-sendevent+                    25)
(defconstant +x-grabpointer+                  26)
(defconstant +x-ungrabpointer+                27)
(defconstant +x-grabbutton+                   28)
(defconstant +x-ungrabbutton+                 29)
(defconstant +x-changeactivepointergrab+      30)
(defconstant +x-grabkeyboard+                 31)
(defconstant +x-ungrabkeyboard+               32)
(defconstant +x-grabkey+                      33)
(defconstant +x-ungrabkey+                    34)
(defconstant +x-allowevents+                  35)
(defconstant +x-grabserver+                   36)
(defconstant +x-ungrabserver+                 37)
(defconstant +x-querypointer+                 38)
(defconstant +x-getmotionevents+              39)
(defconstant +x-translatecoords+              40)
(defconstant +x-warppointer+                  41)
(defconstant +x-setinputfocus+                42)
(defconstant +x-getinputfocus+                43)
(defconstant +x-querykeymap+                  44)
(defconstant +x-openfont+                     45)
(defconstant +x-closefont+                    46)
(defconstant +x-queryfont+                    47)
(defconstant +x-querytextextents+             48)
(defconstant +x-listfonts+                    49)
(defconstant +x-listfontswithinfo+            50)
(defconstant +x-setfontpath+                  51)
(defconstant +x-getfontpath+                  52)
(defconstant +x-createpixmap+                 53)
(defconstant +x-freepixmap+                   54)
(defconstant +x-creategc+                     55)
(defconstant +x-changegc+                     56)
(defconstant +x-copygc+                       57)
(defconstant +x-setdashes+                    58)
(defconstant +x-setcliprectangles+            59)
(defconstant +x-freegc+                       60)
(defconstant +x-cleartobackground+            61)
(defconstant +x-copyarea+                     62)
(defconstant +x-copyplane+                    63)
(defconstant +x-polypoint+                    64)
(defconstant +x-polyline+                     65)
(defconstant +x-polysegment+                  66)
(defconstant +x-polyrectangle+                67)
(defconstant +x-polyarc+                      68)
(defconstant +x-fillpoly+                     69)
(defconstant +x-polyfillrectangle+            70)
(defconstant +x-polyfillarc+                  71)
(defconstant +x-putimage+                     72)
(defconstant +x-getimage+                     73)
(defconstant +x-polytext8+                    74)
(defconstant +x-polytext16+                   75)
(defconstant +x-imagetext8+                   76)
(defconstant +x-imagetext16+                  77)
(defconstant +x-createcolormap+               78)
(defconstant +x-freecolormap+                 79)
(defconstant +x-copycolormapandfree+          80)
(defconstant +x-installcolormap+              81)
(defconstant +x-uninstallcolormap+            82)
(defconstant +x-listinstalledcolormaps+       83)
(defconstant +x-alloccolor+                   84)
(defconstant +x-allocnamedcolor+              85)
(defconstant +x-alloccolorcells+              86)
(defconstant +x-alloccolorplanes+             87)
(defconstant +x-freecolors+                   88)
(defconstant +x-storecolors+                  89)
(defconstant +x-storenamedcolor+              90)
(defconstant +x-querycolors+                  91)
(defconstant +x-lookupcolor+                  92)
(defconstant +x-createcursor+                 93)
(defconstant +x-createglyphcursor+            94)
(defconstant +x-freecursor+                   95)
(defconstant +x-recolorcursor+                96)
(defconstant +x-querybestsize+                97)
(defconstant +x-queryextension+               98)
(defconstant +x-listextensions+               99)
(defconstant +x-setkeyboardmapping+           100)
(defconstant +x-getkeyboardmapping+           101)
(defconstant +x-changekeyboardcontrol+        102)
(defconstant +x-getkeyboardcontrol+           103)
(defconstant +x-bell+                         104)
(defconstant +x-changepointercontrol+         105)
(defconstant +x-getpointercontrol+            106)
(defconstant +x-setscreensaver+               107)
(defconstant +x-getscreensaver+               108)
(defconstant +x-changehosts+                  109)
(defconstant +x-listhosts+                    110)
(defconstant +x-changeaccesscontrol+          111)
(defconstant +x-changeclosedownmode+          112)
(defconstant +x-killclient+                   113)
(defconstant +x-rotateproperties+             114)
(defconstant +x-forcescreensaver+             115)
(defconstant +x-setpointermapping+            116)
(defconstant +x-getpointermapping+            117)
(defconstant +x-setmodifiermapping+           118)
(defconstant +x-getmodifiermapping+           119)
(defconstant +x-nooperation+                  127)

;;; Some macros for threaded lists

(defmacro threaded-atomic-push (item list next type)
  (let ((x (gensym))
        (y (gensym)))
    `(let ((,x ,item))
       (declare (type ,type ,x))
       (loop
          (let ((,y ,list))
            (declare (type (or null ,type) ,y)
                     (optimize (speed 3) (safety 0)))
            (setf (,next ,x) ,y)
            (when (conditional-store ,list ,y ,x)
              (return ,x)))))))

(defmacro threaded-atomic-pop (list next type)
  (let ((y (gensym)))
    `(loop
        (let ((,y ,list))
          (declare (type (or null ,type) ,y)
                   (optimize (speed 3) (safety 0)))
          (if (null ,y)
              (return nil)
              (when (conditional-store ,list ,y (,next (the ,type ,y)))
                (setf (,next (the ,type ,y)) nil)
                (return ,y)))))))

(defmacro threaded-nconc (item list next type)
  (let ((first (gensym))
        (x (gensym))
        (y (gensym))
        (z (gensym)))
    `(let ((,z ,item)
           (,first ,list))
       (declare (type ,type ,z)
                (type (or null ,type) ,first)
                (optimize (speed 3) (safety 0)))
       (if (null ,first)
           (setf ,list ,z)
           (do* ((,x ,first ,y)
                 (,y (,next ,x) (,next ,x)))
                ((null ,y)
                 (setf (,next ,x) ,z)
                 ,first)
             (declare (type ,type ,x)
                      (type (or null ,type) ,y)))))))

(defmacro threaded-push (item list next type)
  (let ((x (gensym)))
    `(let ((,x ,item))
       (declare (type ,type ,x)
                (optimize (speed 3) (safety 0)))
       (shiftf (,next ,x) ,list ,x)
       ,x)))

(defmacro threaded-pop (list next type)
  (let ((x (gensym)))
    `(let ((,x ,list))
       (declare (type (or null ,type) ,x)
                (optimize (speed 3) (safety 0)))
       (when ,x
         (shiftf ,list (,next (the ,type ,x)) nil))
       ,x)))

(defmacro threaded-enqueue (item head tail next type)
  (let ((x (gensym)))
    `(let ((,x ,item))
       (declare (type ,type ,x)
                (optimize (speed 3) (safety 0)))
       (if (null ,tail)
           (threaded-nconc ,x ,head ,next ,type)
           (threaded-nconc ,x (,next (the ,type ,tail)) ,next ,type))
       (setf ,tail ,x))))

(defmacro threaded-dequeue (head tail next type)
  (let ((x (gensym)))
    `(let ((,x ,head))
       (declare (type (or null ,type) ,x)
                (optimize (speed 3) (safety 0)))
       (when ,x
         (when (eq ,x ,tail)
           (setf ,tail (,next (the ,type ,x))))
         (setf ,head (,next (the ,type ,x))))
       ,x)))

(defmacro threaded-requeue (item head tail next type)
  (let ((x (gensym)))
    `(let ((,x ,item))
       (declare (type ,type ,x)
                (optimize (speed 3) (safety 0)))
       (if (null ,tail)
           (setf ,tail (setf ,head ,x))
           (shiftf (,next ,x) ,head ,x))
       ,x)))

(defmacro threaded-dolist ((variable list next type) &body body)
  `(block nil
     (do* ((,variable ,list (,next (the ,type ,variable))))
          ((null ,variable))
       (declare (type (or null ,type) ,variable))
       ,@body)))

(defmacro threaded-delete (item list next type)
  (let ((x (gensym))
        (y (gensym))
        (z (gensym))
        (first (gensym)))
    `(let ((,x ,item)
           (,first ,list))
       (declare (type ,type ,x)
                (type (or null ,type) ,first)
                (optimize (speed 3) (safety 0)))
       (when ,first
         (if (eq ,first ,x)
             (setf ,first (setf ,list (,next ,x)))
             (do* ((,y ,first ,z)
                   (,z (,next ,y) (,next ,y)))
                  ((or (null ,z) (eq ,z ,x))
                   (when (eq ,z ,x)
                     (setf (,next ,y) (,next ,x))))
               (declare (type ,type ,y))
               (declare (type (or null ,type) ,z)))))
       (setf (,next ,x) nil)
       ,first)))

(defmacro threaded-length (list next type)
  (let ((x (gensym))
        (count (gensym)))
    `(do ((,x ,list (,next (the ,type ,x)))
          (,count 0 (index1+ ,count)))
         ((null ,x)
          ,count)
       (declare (type (or null ,type) ,x)
                (type array-index ,count)
                (optimize (speed 3) (safety 0))))))