1 ;;; ez.el --- Emacs Z-machine
3 ;; Copyright (C) 2021 Tim Vaughan
5 ;; Author: Tim Vaughan <timv@ughan.xyz>
6 ;; Created: 13 Oct 2021
9 ;; Homepage: http://thelambdalab.xyz/ez
10 ;; Package-Requires: ((emacs "26"))
12 ;; This file is not part of GNU Emacs.
14 ;; This program is free software: you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation, either version 3 of the License, or
17 ;; (at your option) any later version.
19 ;; This program is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with this file. If not, see <http://www.gnu.org/licenses/>.
33 (defun ez-decode-signed-bits (n nbits)
34 (if (= 0 (lsh n (- 1 nbits)))
38 (defun ez-decode-signed-byte (b)
39 (ez-decode-signed-bits b 8))
41 (defun ez-decode-signed-word (w)
42 (ez-decode-signed-bits w 16))
44 (defun ez-decode-signed-operand (operand operand-type)
45 (if (eq operand-type 'b)
46 (ez-decode-signed-byte operand)
47 (ez-decode-signed-word operand)))
49 (defun binformat (n &optional s)
53 (new-s (concat (number-to-string (mod n 2)) s)))
56 (binformat d new-s))))
58 (defun ez-list-to-string-hex (l)
63 (apply 'concat (mapcar (lambda (n) (format " %x" n)) (cdr l)))))
69 "Memory of z-machine.")
71 (defvar ez-version nil)
73 (defvar ez-start-pc nil)
74 (defvar ez-himem-base nil)
75 (defvar ez-dict-base nil)
76 (defvar ez-objtab-addr nil)
77 (defvar ez-abbrevtab-addr nil)
78 (defvar ez-globalvartab-addr nil)
80 (defun ez-mem-ref-byte (addr)
81 (aref ez-memory addr))
83 (defun ez-mem-set-byte (addr val)
84 (aset ez-memory addr val))
86 (defun ez-mem-ref-word (addr)
87 (+ (* 256 (aref ez-memory addr))
88 (aref ez-memory (+ addr 1))))
90 (defun ez-mem-set-word (addr val)
91 (let ((byte-high (/ val 256))
92 (byte-low (mod val 256)))
93 (aset ez-memory addr byte-high)
94 (aset ez-memory (+ addr 1) byte-low)))
96 (defun ez-parse-header ()
97 (setq ez-version (ez-mem-ref-byte #x0))
98 (setq ez-himem-addr (ez-mem-ref-word #x4))
99 (setq ez-start-pc (ez-mem-ref-word #x6))
100 (setq ez-dict-base (ez-mem-ref-word #x8))
101 (setq ez-objtab-addr (ez-mem-ref-word #xA))
102 (setq ez-globalvartab-addr (ez-mem-ref-word #xC))
103 (setq ez-abbrevtab-addr (ez-mem-ref-word #x18)))
105 (defun ez-load-file (filename)
106 "Load story file into memory."
108 (insert-file-contents-literally filename)
109 (setq ez-memory (encode-coding-string (buffer-string) 'raw-text)))
114 (defun ez-get-global-var (gvar)
116 (error "Invalid global variable %d" gvar))
117 (ez-mem-ref-word (+ (* 2 gvar) ez-globalvartab-addr)))
119 (defun ez-set-global-var (gvar val)
120 (ez-mem-set-word (+ (* 2 gvar) ez-globalvartab-addr) val))
124 (defvar ez-property-defaults nil)
126 (defun ez-load-property-defaults ()
127 (setq ez-property-defaults (make-vector 31 0))
129 (aset ez-property-defaults i (aref ez-memory (+ ez-objtab-addr (* 2 i))))))
131 (defun ez-get-obj-addr (obj)
132 (+ ez-objtab-addr (* 2 31) (* 9 (- obj 1))))
134 (defun ez-get-obj-parent (obj)
135 (let ((addr (ez-get-obj-addr obj)))
136 (ez-mem-ref-byte (+ addr 4))))
138 (defun ez-set-obj-parent (obj new-parent)
139 (let ((addr (ez-get-obj-addr obj)))
140 (ez-mem-set-byte (+ addr 4) new-parent)))
142 (defun ez-get-obj-sibling (obj)
143 (let ((addr (ez-get-obj-addr obj)))
144 (ez-mem-ref-byte (+ addr 5))))
146 (defun ez-set-obj-sibling (obj new-sibling)
147 (let ((addr (ez-get-obj-addr obj)))
148 (ez-mem-set-byte (+ addr 5) new-sibling)))
150 (defun ez-get-obj-child (obj)
151 (let ((addr (ez-get-obj-addr obj)))
152 (ez-mem-ref-byte (+ addr 6))))
154 (defun ez-set-obj-child (obj new-child)
155 (let ((addr (ez-get-obj-addr obj)))
156 (ez-mem-set-byte (+ addr 6) new-child)))
158 (defun ez-get-obj-plist-addr (obj)
159 (let ((addr (ez-get-obj-addr obj)))
160 (ez-mem-ref-word (+ addr 7))))
162 (defun ez-get-obj-name (obj)
163 (let ((plist-addr (ez-get-obj-plist-addr obj)))
164 (if (> (ez-mem-ref-byte plist-addr) 0)
165 (ez-get-zstring (+ 1 (ez-get-obj-plist-addr obj)))
168 (defun ez-get-prop-default (prop)
169 (ez-mem-ref-word (+ ez-objtab-addr (* 2 (+ 1 prop)))))
171 (defun ez-get-prop-len (prop-size-byte)
172 (lsh prop-size-byte -5))
174 (defun ez-get-prop-num (prop-size-byte)
175 (logand #b00011111 prop-size-byte))
177 (defun ez-get-obj-prop-addr (obj prop)
178 (let* ((plist-addr (ez-get-obj-plist-addr obj))
179 (prop-addr (+ plist-addr 1 (* 2 (ez-mem-ref-byte plist-addr))))
180 (size-byte (ez-mem-ref-byte prop-addr)))
181 (while (not (or (= size-byte 0)
182 (= prop (ez-get-prop-num size-byte))))
183 (setq prop-addr (+ prop-addr (ez-get-prop-len size-byte) 2)
184 size-byte (ez-mem-ref-byte prop-addr)))
187 (defun ez-get-obj-prop (obj prop)
188 (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
189 (size-byte (ez-mem-ref-byte prop-addr)))
191 (ez-get-prop-default prop)
192 (let ((prop-len (ez-get-prop-len size-byte))
193 (data-addr (+ prop-addr 1)))
196 (ez-mem-ref-byte data-addr))
198 (ez-mem-ref-word data-addr)))))))
200 (defun ez-set-obj-prop (obj prop value)
201 (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
202 (size-byte (ez-mem-ref-byte prop-addr)))
205 (error "Tried to set non-existant property"))
206 ((= (ez-get-prop-len size-byte) 1)
207 (ez-mem-set-byte (+ prop-addr 1) value))
209 (ez-mem-set-word (+ prop-addr 1) value)))))
211 (defun ez-get-obj-attr (obj attr)
212 (let* ((byte-num (/ attr 8))
213 (bit-num (mod attr 8))
214 (bit-mask (lsh 1 (- 7 bit-num))))
215 (if (> (logand bit-mask (ez-mem-ref-byte (+ (ez-get-obj-addr obj) byte-num))) 0)
219 (defun ez-set-obj-attr (obj attr val)
220 (let* ((byte-num (/ attr 8))
221 (bit-num (mod attr 8))
222 (bit-mask (lsh 1 (- 7 bit-num)))
223 (byte-addr (+ (ez-get-obj-addr obj) byte-num))
224 (byte (ez-mem-ref-byte byte-addr))
225 (current-set (> (logand bit-mask byte) 0)))
226 (if (or (and current-set (= val 0))
227 (and (not current-set) (> val 0)))
228 (ez-mem-set-byte byte-addr (logxor byte bit-mask)))))
231 (defun ez-remove-obj (obj)
232 (let ((parent (ez-get-obj-parent obj))
233 (sibling (ez-get-obj-sibling obj)))
235 (let ((child (ez-get-obj-child parent)))
237 (ez-set-obj-child parent sibling)
238 (while (not (= obj (ez-get-obj-sibling child)))
239 (setq child (ez-get-obj-sibling child)))
240 (ez-set-obj-sibling child (ez-get-obj-sibling obj))))
241 (ez-set-obj-parent obj 0))
242 (ez-set-obj-sibling obj 0)))
244 (defun ez-insert-obj (obj new-parent)
246 (unless (= new-parent 0)
247 (ez-set-obj-sibling obj (ez-get-obj-child new-parent))
248 (ez-set-obj-child new-parent obj)))
252 (defvar ez-zstring-alphabets
255 (list " abcdefghijklmnopqrstuvwxyz"
256 " ABCDEFGHIJKLMNOPQRSTUVWXYZ"
257 " \n0123456789.,!?_#'\"/\\-:()")
258 "Alphabets used by V3")
260 (defun ez-parse-zstring-word (word)
262 (logand (lsh word -10) #b11111)
263 (logand (lsh word -5) #b11111)
264 (logand word #b11111)))
266 (defun ez-get-zstring-chars-and-length (base-addr)
267 (let ((addr base-addr)
272 (let ((components (ez-parse-zstring-word (ez-mem-ref-word addr))))
273 (setq chars (append chars (cdr components)))
274 (setq addr (+ addr 2))
275 (setq word-count (+ word-count 1))
276 (when (= (car components) 1)
277 (setq not-done nil))))
278 (cons word-count chars)))
280 (defun ez-get-zstring-and-length (base-addr)
281 (let* ((word-count-and-chars (ez-get-zstring-chars-and-length base-addr))
282 (word-count (car word-count-and-chars))
283 (chars (cdr word-count-and-chars))
292 (* 2 (ez-mem-ref-word (+ ez-abbrevtab-addr
293 (* 2 (+ (* (- abbrev-char 1) 32) char)))))))
294 (setq s (concat s (cdr (ez-get-zstring-and-length abbrev-addr)))))
295 (setq abbrev-char nil))
296 ((memq char '(1 2 3)) ;Abbreviation
297 (setq abbrev-char char))
299 (setq cur (mod (+ cur 1) 3)))
301 (setq cur (mod (+ 3 (- cur 1)) 3)))
303 (setq s (concat s (substring (elt ez-zstring-alphabets cur)
306 (cons word-count s)))
308 (defun ez-get-zstring (base-addr)
309 (cdr (ez-get-zstring-and-length base-addr)))
314 (defvar ez-call-stack nil)
316 (defun ez-make-call-stack-frame (pc &optional call-method)
322 (defun ez-add-call-stack-frame (pc &optional call-method)
323 (push (ez-make-call-stack-frame pc call-method) ez-call-stack))
325 (defun ez-pop-call-stack-frame ()
328 (defun ez-routine-stack ()
329 (elt (car ez-call-stack) 1))
331 (defun ez-routine-stack-push (val)
332 (let ((frame (car ez-call-stack)))
333 (setf (elt frame 1) (cons val (elt frame 1)))))
335 (defun ez-routine-stack-pop ()
336 (let* ((frame (car ez-call-stack))
337 (rs-head (car (elt frame 1))))
338 (setf (elt frame 1) (cdr (elt frame 1)))
341 (defun ez-get-local-var (lvar)
342 (let ((frame (car ez-call-stack)))
343 (aref (elt frame 2) (- lvar 1))))
345 (defun ez-set-local-var (lvar val)
346 (let ((frame (car ez-call-stack)))
347 (aset (elt frame 2) (- lvar 1) val)))
350 (caar ez-call-stack))
352 (defun ez-set-pc (new-pc)
353 (setf (car (car ez-call-stack)) new-pc))
355 (defun ez-increment-pc (inc)
356 (ez-set-pc (+ (ez-get-pc) inc)))
358 (defun ez-read-pc-byte-and-inc ()
359 (let ((res (ez-mem-ref-byte (ez-get-pc))))
363 (defun ez-read-pc-word-and-inc ()
364 (let ((res (ez-mem-ref-word (ez-get-pc))))
368 ;; Instruction execution
370 (defun ez-get-var (var)
373 (ez-routine-stack-pop))
375 (ez-get-local-var var))
377 (ez-get-global-var (- var 16)))))
379 (defun ez-set-var (var val)
382 (message "Pushed %x to stack" val)
383 (ez-routine-stack-push val))
385 (message "Saved %x to local variable %x" val var)
386 (ez-set-local-var var val))
388 (message "Saved %x to global variable %x" val (- var 16))
389 (ez-set-global-var (- var 16) val))))
391 (defun ez-read-pc-var-and-inc ()
392 (ez-get-var (ez-read-pc-byte-and-inc)))
394 (defun ez-execute-instr ()
395 (let ((instr-pc (ez-get-pc))
396 (opbyte (ez-read-pc-byte-and-inc))
397 (optype) (opcode) (operands))
399 ((<= #x0 opbyte #x1f)
402 operands (list (ez-read-pc-byte-and-inc)
403 (ez-read-pc-byte-and-inc))
404 operand-types '(b b)))
405 ((<= #x20 opbyte #x3F)
407 opcode (- opbyte #x20)
408 operands (list (ez-read-pc-byte-and-inc)
409 (ez-read-pc-var-and-inc))
410 operand-types '(b w)))
411 ((<= #x40 opbyte #x5F)
413 opcode (- opbyte #x40)
414 operands (list (ez-read-pc-var-and-inc)
415 (ez-read-pc-byte-and-inc))
416 operand-types '(w b)))
417 ((<= #x60 opbyte #x7F)
419 opcode (- opbyte #x60)
420 operands (list (ez-read-pc-var-and-inc)
421 (ez-read-pc-var-and-inc))
422 operand-types '(w w)))
423 ((<= #x80 opbyte #x8F)
425 opcode (- opbyte #x80)
426 operands (list (ez-read-pc-word-and-inc))
428 ((<= #x90 opbyte #x9F)
430 opcode (- opbyte #x90)
431 operands (list (ez-read-pc-byte-and-inc))
433 ((<= #xA0 opbyte #xAF)
435 opcode (- opbyte #xa0)
436 operands (list (ez-read-pc-var-and-inc))
438 ((<= #xB0 opbyte #xBF)
440 opcode (- opbyte #xb0)
443 ((<= #xC0 opbyte #xDF)
445 opcode (- opbyte #xc0))
446 (let ((operands-and-types (ez-read-var-operands-and-inc)))
447 (setq operands (car operands-and-types)
448 operand-types (cdr operands-and-types))))
449 ((<= #xE0 opbyte #xFF)
451 opcode (- opbyte #xe0))
452 (let ((operands-and-types (ez-read-var-operands-and-inc)))
453 (setq operands (car operands-and-types)
454 operand-types (cdr operands-and-types)))))
455 (let ((table-row (assoc (list optype opcode) ez-op-table)))
457 (error "Unsupported op PC:%x Optype:%s Opcode:%x Operands:%s Operand-types:%s"
458 instr-pc optype opcode (ez-list-to-string-hex operands) operand-types))
459 (let ((mnemonic (elt table-row 1)))
460 (message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s Operand-types:%s"
461 instr-pc optype opcode mnemonic
462 (ez-list-to-string-hex operands) operand-types))
463 (funcall (elt table-row 2) operands operand-types))))
465 (defun ez-read-var-operands-and-inc ()
466 (let* ((type-byte (ez-read-pc-byte-and-inc))
467 (types (let ((type1 (lsh type-byte -6)))
471 (let ((type2 (lsh (logand #b110000 type-byte) -4)))
475 (let ((type3 (lsh (logand #b1100 type-byte) -2)))
479 (let ((type4 (logand #b11)))
482 (list type4))))))))))))))
487 ((= type 0) (ez-read-pc-word-and-inc))
488 ((= type 1) (ez-read-pc-byte-and-inc))
489 ((= type 2) (ez-read-pc-var-and-inc))))
500 (defun ez-do-branch (branch)
501 (let* ((branch-byte (ez-read-pc-byte-and-inc))
502 (invert (= 0 (logand branch-byte #b10000000)))
503 (single-byte (> (logand branch-byte #b01000000) 0))
506 (logand branch-byte #b00111111)
507 (let ((pos (= (logand branch-byte #b00100000) 0))
508 (val (+ (* 256 (logand branch-byte #b00011111))
509 (ez-read-pc-byte-and-inc))))
513 (if (or (and branch (not invert))
514 (and (not branch) invert))
521 (ez-set-pc (+ (ez-get-pc) offset -2)))))))
526 '(((0op #x00) rtrue ez-op-rtrue)
527 ((0op #x01) rfalse ez-op-rfalse)
528 ((1op #x00) jz ez-op-jz)
529 ((1op #x05) inc ez-op-inc)
530 ((1op #x06) dec ez-op-dec)
531 ((1op #x0B) ret ez-op-ret)
532 ((1op #x0C) jump ez-op-jump)
533 ((2op #x05) inc_jg ez-op-inc-jg)
534 ((2op #x04) dec_jg ez-op-dec-jg)
535 ((2op #x0D) store ez-op-store)
536 ((1op #x0E) load ez-op-load)
537 ((var #x01) storew ez-op-storew)
538 ((2op #x0F) loadw ez-op-loadw)
539 ((var #x02) storeb ez-op-storeb)
540 ((2op #x10) loadb ez-op-loadb)
541 ((2op #x01) je ez-op-je)
542 ((2op #x02) jl ez-op-jl)
543 ((2op #x06) jin ez-op-jin)
544 ((2op #x08) or ez-op-or)
545 ((2op #x09) and ez-op-and)
546 ((2op #x14) add ez-op-add)
547 ((2op #x15) sub ez-op-sub)
548 ((2op #x16) mul ez-op-mul)
549 ((2op #x17) div ez-op-div)
550 ((2op #x18) mod ez-op-mod)
551 ((var #x00) call_fv ez-op-callf)
552 ((1op #x01) get_sibling ez-op-get-sibling)
553 ((1op #x02) get_child ez-op-get-child)
554 ((1op #x03) get_parent ez-op-get-parent)
555 ((2op #x0A) test_attr ez-op-test-attr)
556 ((2op #x0B) set_attr ez-op-set-attr)
557 ((2op #x0C) clear_attr ez-op-clear-attr)
558 ((1op #x09) remove_obj ez-op-remove-obj)
559 ((2op #x0E) insert_obj ez-op-insert-obj)
560 ((var #x03) put_prop ez-op-put-prop)
561 ((2op #x11) get_prop ez-op-get-prop)
562 ((0op #x02) print ez-op-print)
563 ((0op #x0B) new_line ez-op-new-line)
564 ((var #x06) print_num ez-op-print-num)
565 ((var #x05) print_char ez-op-print-char)
566 ((1op #x0A) print_obj ez-op-print-obj)))
568 (defun ez-op-ret (operands &optional operand-types)
569 (let ((retval (car operands)))
570 (ez-pop-call-stack-frame)
571 (ez-set-var (ez-read-pc-byte-and-inc) retval))
574 (defun ez-op-rtrue (&optional operands operand-types)
578 (defun ez-op-rfalse (&optional operands operand-types)
582 (defun ez-op-jz (operands operand-types)
583 (ez-do-branch (= (car operands) 0))
586 (defun ez-op-je (operands operand-types)
587 (ez-do-branch (memq (car operands) (cdr operands)))
590 (defun ez-op-jg (operands operand-types)
591 (let ((s1 (ez-decode-signed-operand (car operands) (car operand-types)))
592 (s2 (ez-decode-signed-operand (cadr operands) (cadr operand-types))))
593 (ez-do-branch (> s1 s2)))
596 (defun ez-op-jl (operands operand-types)
597 (let ((s1 (ez-decode-signed-operand (car operands) (car operand-types)))
598 (s2 (ez-decode-signed-operand (cadr operands) (cadr operand-types))))
599 (ez-do-branch (< s1 s2)))
602 (defun ez-op-inc-jg (operands operand-types)
603 (let ((var (car operands)))
604 (ez-op-inc (list var))
605 (ez-op-jg (cons (ez-get-var var) (cdr operands)) (cons 'w (cdr operand-types))))
608 (defun ez-op-dec-jl (operands operand-types)
609 (let ((var (car operands)))
610 (ez-op-dec (list var))
611 (ez-op-jl (cons (ez-get-var var) (cdr operands)) (cons 'w (cdr operand-types))))
614 (defun ez-op-jin (operands operand-types)
615 (let ((obj (car operands))
617 (ez-do-branch (or (= n 0)
618 (= n (ez-get-obj-parent obj)))))
621 (defun ez-op-jump (operands operand-types)
622 (let ((offset (if (eq (car operand-types) 'b)
623 (ez-decode-signed-byte (car operands))
624 (ez-decode-signed-word (car operands)))))
625 (ez-set-pc (+ (ez-get-pc) offset -2)))
628 (defun ez-op-inc (operands &optional operand-types)
629 (let ((var (car operands)))
630 (ez-set-var var (mod (+ 1 (ez-get-var var)) #x10000)))
633 (defun ez-op-dec (operands &optional operand-types)
634 (let ((var (car operands)))
635 (ez-set-var var (mod (+ (ez-get-var var) 1) #x10000)))
638 (defun ez-op-store (operands operand-types)
639 (let ((var (car operands))
644 (defun ez-op-load (operands operand-types)
645 (let ((var (car operands)))
646 (ez-set-var (ez-read-pc-byte-and-inc) (ez-get-var var)))
649 (defun ez-op-storew (operands operand-types)
650 (let ((baddr (car operands))
652 (a (caddr operands)))
653 (ez-mem-set-word (+ baddr (* 2 n)) a))
656 (defun ez-op-loadw (operands operand-types)
657 (let ((baddr (car operands))
659 (ez-set-var (ez-read-pc-byte-and-inc) (ez-mem-ref-word (+ baddr (* 2 n)))))
662 (defun ez-op-storeb (operands operand-types)
663 (let ((baddr (car operands))
665 (a (caddr operands)))
666 (ez-mem-set-byte (+ baddr n) a))
669 (defun ez-op-loadb (operands operand-types)
670 (let ((baddr (car operands))
672 (ez-set-var (ez-read-pc-byte-and-inc) (ez-mem-ref-byte (+ baddr n))))
675 (defun ez-op-and (operands operand-types)
676 (let ((a (car operands))
678 (ez-set-var (ez-read-pc-byte-and-inc) (logand a b)))
681 (defun ez-op-or (operands operand-types)
682 (let ((a (car operands))
684 (ez-set-var (ez-read-pc-byte-and-inc) (logior a b)))
687 (defun ez-op-add (operands operand-types)
688 (let ((a (car operands))
690 (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ a b) #x10000)))
693 (defun ez-op-sub (operands operand-types)
694 (let ((a (car operands))
696 (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ (- a b) #x10000) #x10000)))
699 (defun ez-op-mul (a b)
700 (let ((a (car operands))
702 (ez-set-var (ez-read-pc-byte-and-inc) (mod (* a b) #x10000)))
705 (defun ez-op-div (a b)
706 (error "Not implemented"))
708 (defun ez-op-mod (a b)
709 (error "Not implemented"))
711 (defun ez-op-callf (operands operand-types)
712 (let* ((raddr (car operands))
713 (call-operands (cdr operands))
715 (L (ez-mem-ref-byte r))
716 (n (length call-operands))
717 (new-pc (+ r 1 (* L 2))))
718 (ez-add-call-stack-frame new-pc)
721 (ez-set-local-var (+ i 1) (elt call-operands i))
722 (ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i)))))))
725 (defun ez-op-test-attr (operands operand-types)
726 (let ((obj (car operands))
727 (attr (cadr operands)))
728 (ez-do-branch (= 1 (ez-get-obj-attr obj attr)))
731 (defun ez-op-set-attr (operands operand-types)
732 (let ((obj (car operands))
733 (attr (cadr operands)))
734 (ez-set-obj-attr obj attr 1))
737 (defun ez-op-clear-attr (operands operand-types)
738 (let ((obj (car operands))
739 (attr (cadr operands)))
740 (ez-set-obj-attr obj attr 0))
743 (defun ez-op-get-sibling (operands operand-types)
744 (let ((sib (ez-get-obj-sibling (car operands))))
745 (ez-set-var (ez-read-pc-byte-and-inc) sib)
746 (ez-do-branch (> sib 0)))
749 (defun ez-op-get-child (operands operand-types)
750 (let ((child (ez-get-obj-child (car operands))))
751 (ez-set-var (ez-read-pc-byte-and-inc) child)
752 (ez-do-branch (> child 0)))
755 (defun ez-op-get-parent (operands operand-types)
756 (let ((parent (ez-get-obj-parent (car operands))))
757 (ez-set-var (ez-read-pc-byte-and-inc) parent))
760 (defun ez-op-remove-obj (operands operand-types)
761 (let ((obj (car operands)))
765 (defun ez-op-insert-obj (operands operand-types)
766 (let ((obj1 (car operands))
767 (obj2 (cadr operands)))
768 (ez-insert-obj obj1 obj2))
771 (defun ez-op-put-prop (operands operand-types)
772 (let* ((obj (car operands))
773 (prop (cadr operands))
774 (a (caddr operands)))
775 (ez-set-obj-prop obj prop a))
778 (defun ez-op-get-prop (operands operand-types)
779 (let* ((obj (car operands))
780 (prop (cadr operands)))
781 (ez-set-var (ez-read-pc-byte-and-inc)
782 (ez-get-obj-prop obj prop)))
785 (defun ez-op-print (operands operand-types)
786 (let* ((word-count-and-string (ez-get-zstring-and-length (ez-get-pc)))
787 (word-count (car word-count-and-string))
788 (string (cdr word-count-and-string)))
790 (ez-increment-pc (* 2 word-count)))
793 (defun ez-op-new-line (operands operand-types)
797 (defun ez-op-print-num (operands operand-types)
798 (let ((s (ez-decode-signed-operand (car operands) (car operand-types))))
799 (ez-print (number-to-string s)))
802 (defun ez-op-print-char (operands operand-types)
803 (let ((c (car operands)))
804 (ez-print (string c)))
807 (defun ez-op-print-obj (operands operand-types)
808 (let ((obj (car operands)))
809 (ez-print (ez-get-obj-name obj)))
814 (defun ez-run (filename)
815 (ez-load-file filename)
817 (setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
819 (while (ez-execute-instr)))
825 (defun ez-render-prompt ()
826 (with-current-buffer "*ez*"
827 (let ((update-point (= ez-input-marker (point)))
828 (update-window-points (mapcar (lambda (w)
829 (list (= (window-point w) ez-input-marker)
831 (get-buffer-window-list nil nil t))))
833 (set-marker-insertion-type ez-prompt-marker nil)
834 (set-marker-insertion-type ez-input-marker t)
835 (let ((inhibit-read-only t))
836 (delete-region ez-prompt-marker ez-input-marker)
837 (goto-char ez-prompt-marker)
840 (propertize " " ; Need this to be separate to mark it as rear-nonsticky
843 (set-marker-insertion-type ez-input-marker nil))
844 (goto-char ez-input-marker))))
846 (defvar ez-prompt-marker nil
847 "Marker for prompt position in buffer.")
849 (defvar ez-input-marker nil
850 "Marker for prompt position in buffer.")
852 (defun ez-setup-buffer ()
853 (with-current-buffer (get-buffer-create "*ez*")
854 (let ((inhibit-read-only t))
855 (delete-region (point-min) (point-max)))
856 (setq-local scroll-conservatively 1)
857 (if (markerp ez-prompt-marker)
858 (set-marker ez-prompt-marker (point-max))
859 (setq ez-prompt-marker (point-max-marker)))
860 (if (markerp ez-input-marker)
861 (set-marker ez-input-marker (point-max))
862 (setq ez-input-marker (point-max-marker)))
863 (goto-char (point-max))
867 (defun ez-print (string)
868 (with-current-buffer "*ez*"
870 (goto-char ez-prompt-marker)
871 (insert-before-markers string))))
876 (let ((map (make-sparse-keymap)))
877 (define-key map (kbd "RET") 'ez-enter)
880 (define-derived-mode ez-mode text-mode "ez"
881 "Major mode for EZ.")
883 (when (fboundp 'evil-set-initial-state)
884 (evil-set-initial-state 'ez-mode 'insert))
887 (interactive "fEnter name of z3 story file: ")
888 (if (get-buffer "*ez*")
889 (switch-to-buffer "*ez*")
890 (switch-to-buffer "*ez*")
898 (switch-to-buffer "*ez*")