;;; ez.el --- Emacs Z-machine
-;; Copyright (C) 2021 Tim Vaughan
+;; Copyright (C) 2021,2022,2023 Tim Vaughan
-;; Author: Tim Vaughan <timv@ughan.xyz>
+;; Author: Tim Vaughan <plugd@thelambdalab.xyz>
;; Created: 13 Oct 2021
;; Version: 1.0
;; Keywords: game
(defvar ez-abbrevtab-addr nil)
(defvar ez-globalvartab-addr nil)
+(defvar ez-dict-entries nil
+ "Parsed dictionary")
+
+(defvar ez-dict-separators nil
+ "Parsed dictionary")
+
(defun ez-mem-ref-byte (addr)
(aref ez-memory addr))
+(defun ez-mem-ref-bytes (addr count)
+ (mapcar (lambda (offset) (ez-mem-ref-byte (+ addr offset)))
+ (number-sequence 0 (- count 1))))
+
(defun ez-mem-set-byte (addr val)
(aset ez-memory addr val))
+(defun ez-mem-set-bytes (addr vals)
+ (dotimes (i (length vals))
+ (ez-mem-set-byte (+ addr i) (elt vals i))))
+
(defun ez-mem-ref-word (addr)
- (+ (* 256 (aref ez-memory addr))
- (aref ez-memory (+ addr 1))))
+ (logior (lsh (aref ez-memory addr) 8)
+ (aref ez-memory (+ addr 1))))
+
+(defun ez-mem-ref-words (addr count)
+ (mapcar (lambda (offset) (ez-mem-ref-word (+ addr offset)))
+ (number-sequence 0 (- (* 2 count) 1) 2)))
(defun ez-mem-set-word (addr val)
(let ((byte-high (/ val 256))
(aset ez-memory addr byte-high)
(aset ez-memory (+ addr 1) byte-low)))
+(defun ez-mem-ref-string (addr1 addr2)
+ (substring ez-memory addr1 addr2))
+
(defun ez-parse-header ()
(setq ez-version (ez-mem-ref-byte #x0))
(setq ez-himem-addr (ez-mem-ref-word #x4))
(error "Invalid global variable %d" gvar))
(let ((val
(ez-mem-ref-word (+ (* 2 gvar) ez-globalvartab-addr))))
- (message "\tRetrieved %x from global variable %x" val gvar)
+ (ez-debug-message "\tRetrieved %x from global variable %x" val gvar)
val))
(defun ez-set-global-var (gvar val)
(ez-mem-set-word (+ (* 2 gvar) ez-globalvartab-addr) val)
- (message "\tSet global variabl %x to %x" gvar val))
+ (ez-debug-message "\tSet global variabl %x to %x" gvar val))
;; Object tree
(logand (lsh word -5) #b11111)
(logand word #b11111)))
+(defun ez-make-zstring-word (zchar-triple)
+ (let ((c1 (elt zchar-triple 0))
+ (c2 (elt zchar-triple 1))
+ (c3 (elz zchar-triple 2)))
+ (logand )))
+
(defun ez-get-zstring-chars-and-length (base-addr)
(let ((addr base-addr)
(chars nil)
(chars (cdr word-count-and-chars))
(cur 0)
(lock 0)
- (abbrev-char nil)
(s ""))
- (dolist (char chars)
- (cond
- (abbrev-char
- (let ((abbrev-addr
- (* 2 (ez-mem-ref-word (+ ez-abbrevtab-addr
- (* 2 (+ (* (- abbrev-char 1) 32) char)))))))
- (setq s (concat s (cdr (ez-get-zstring-and-length abbrev-addr)))))
- (setq abbrev-char nil))
- ((memq char '(1 2 3)) ;Abbreviation
- (setq abbrev-char char))
- ((= char 4)
- (setq cur (mod (+ cur 1) 3)))
- ((= char 5)
- (setq cur (mod (+ 3 (- cur 1)) 3)))
- (t
- (setq s (concat s (substring (elt ez-zstring-alphabets cur)
- char (+ char 1))))
- (setq cur lock))))
+ (while (> (length chars) 0)
+ (let ((char (pop chars)))
+ (cond
+ ((memq char '(1 2 3)) ;Abbreviation
+ (let* ((abbrev-char char)
+ (abbrev-addr
+ (* 2 (ez-mem-ref-word (+ ez-abbrevtab-addr
+ (* 2 (+ (* (- abbrev-char 1) 32) (pop chars))))))))
+ (setq s (concat s (cdr (ez-get-zstring-and-length abbrev-addr))))))
+ ((= char 4)
+ (setq cur (mod (+ cur 1) 3)))
+ ((= char 5)
+ (setq cur (mod (+ 3 (- cur 1)) 3)))
+ ((and (= cur 2) (= char 6))
+ (setq s (concat s (char-to-string (+ (lsh (pop chars) 5) (pop chars)))))
+ (setq cur lock))
+ (t
+ (setq s (concat s (substring (elt ez-zstring-alphabets cur)
+ char (+ char 1))))
+ (setq cur lock)))))
(cons word-count s)))
(defun ez-get-zstring (base-addr)
(cdr (ez-get-zstring-and-length base-addr)))
+(defun ez-encode (string)
+ "Encodes a string as a 2-word 5-padded Z-string.
+Used for matching input with dictionary entries when tokenizing.
+Returns a length-2 list of words for comparison with a dictionary entry."
+ (let ((chars
+ (mapcan
+ (lambda (c)
+ (cond
+ ((seq-contains-p (elt ez-zstring-alphabets 0) c)
+ (list (seq-position (elt ez-zstring-alphabets 0) c)))
+ ((seq-contains-p (elt ez-zstring-alphabets 1) c)
+ (list 4 (seq-position (elt ez-zstring-alphabets 1) c)))
+ ((seq-contains-p (elt ez-zstring-alphabets 2) c)
+ (list 5 (seq-position (elt ez-zstring-alphabets 2) c)))
+ (t
+ (list 5 6 (lsh c -5) (logand c #b11111)))))
+ string)))
+ (let* ((zstring-chars
+ (if (< (length chars) 6)
+ (append chars (make-list (- 6 (length chars)) 5))
+ (take 6 chars)))
+ (c1 (elt zstring-chars 0))
+ (c2 (elt zstring-chars 1))
+ (c3 (elt zstring-chars 2))
+ (c4 (elt zstring-chars 3))
+ (c5 (elt zstring-chars 4))
+ (c6 (elt zstring-chars 5)))
+ (list
+ (logior (lsh c1 10)
+ (lsh c2 5)
+ c3)
+ (logior (lsh 1 15)
+ (lsh c4 10)
+ (lsh c5 5)
+ c6)))))
+
+;; Dictionary
+
+(defun ez-parse-dictionary-header ()
+ (let* ((nseps (ez-mem-ref-byte ez-dict-base))
+ (separators
+ (mapcar (lambda (i) (ez-mem-ref-byte (+ ez-dict-base i)))
+ (number-sequence 1 nseps)))
+ (bytes-per-entry (ez-mem-ref-byte (+ ez-dict-base 1 nseps)))
+ (nentries (ez-mem-ref-word (+ ez-dict-base 2 nseps)))
+ (entries-base (+ ez-dict-base nseps 4))
+ (entries nil))
+ ;; (dotimes (i nentries)
+ ;; (let ((this-base (+ entries-base (* bytes-per-entry i))))
+ ;; (setq entries (cons (cons (ez-get-zstring this-base)
+ ;; this-base)
+ ;; entries))))
+ ;; (setq ez-dict-entries (reverse entries))
+ (setq ez-dict-separators separators)))
+
+(defun ez-is-separator (char)
+ (let* ((nseps (ez-mem-ref-byte ez-dict-base)))
+ (while (and (> nseps 0)
+ (not (= (ez-mem-ref-byte (+ ez-dict-base nseps))
+ char)))
+ (setq nseps (- nseps 1)))
+ (> nseps 0)))
+
+(defun ez-lookup-dictionary (text)
+ (let* ((encoded-text (ez-encode text))
+ (nseps (ez-mem-ref-byte ez-dict-base))
+ (bytes-per-entry (ez-mem-ref-byte (+ ez-dict-base 1 nseps)))
+ (nentries (ez-mem-ref-word (+ ez-dict-base 2 nseps)))
+ (entries-seen 0)
+ (this-entry (+ ez-dict-base nseps 4)))
+
+ (while (and (< entries-seen nentries)
+ (not (equal
+ (ez-mem-ref-words this-entry 2)
+ encoded-text)))
+ (setq entries-seen (+ entries-seen 1))
+ (setq this-entry (+ this-entry bytes-per-entry)))
+
+ (if (< entries-seen nentries)
+ this-entry
+ 0)))
+
;; Call stack
(defvar ez-call-stack nil)
(defun ez-routine-stack-push (val)
(let ((frame (car ez-call-stack)))
- (message "\tPushed %x to stack" val)
+ (ez-debug-message "\tPushed %x to stack" val)
(setf (elt frame 1) (cons val (elt frame 1)))))
(defun ez-routine-stack-pop ()
(let* ((frame (car ez-call-stack))
(rs-head (car (elt frame 1))))
(setf (elt frame 1) (cdr (elt frame 1)))
- (message "\tPopped %x from stack" rs-head)
+ (ez-debug-message "\tPopped %x from stack" rs-head)
rs-head))
(defun ez-get-local-var (lvar)
(let* ((frame (car ez-call-stack))
(val (aref (elt frame 2) (- lvar 1))))
- (message "\tRetrieved value %x from local variable %x" val lvar)
+ (ez-debug-message "\tRetrieved value %x from local variable %x" val lvar)
val))
(defun ez-set-local-var (lvar val)
(let ((frame (car ez-call-stack)))
- (message "\tSet local variable %x to %x" lvar val)
+ (ez-debug-message "\tSet local variable %x to %x" lvar val)
(aset (elt frame 2) (- lvar 1) val)))
(defun ez-get-pc ()
(error "Unsupported op PC:%x Optype:%s Opcode:%x Operands:%s Operand-types:%s"
instr-pc optype opcode (ez-list-to-string-hex operands) operand-types))
(let ((mnemonic (elt table-row 1)))
- (message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s Operand-types:%s"
+ (ez-debug-message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s Operand-types:%s"
instr-pc optype opcode mnemonic
(ez-list-to-string-hex operands) operand-types))
(funcall (elt table-row 2) operands operand-types))))
(defun ez-op-ret (operands &optional operand-types)
(let ((retval (car operands)))
- (message "\tReturning value %x" retval)
+ (ez-debug-message "\tReturning value %x" retval)
(ez-pop-call-stack-frame)
(ez-set-var (ez-read-pc-byte-and-inc) retval))
'run)
(defun ez-op-ret-pulled (operands operand-types)
(let ((retval (ez-routine-stack-pop)))
- (message "\tReturning value %x" retval)
+ (ez-debug-message "\tReturning value %x" retval)
(ez-op-ret (list retval)))
'run)
(ez-print (ez-get-obj-name obj)))
'run)
+(defvar ez--next-read-args nil)
(defun ez-op-read (operands operand-types)
(let ((baddr1 (car operands))
(baddr2 (cadr operands)))
- )
+ (setq ez--next-read-args (list baddr1 baddr2)))
'wait-for-input)
+(defun ez-op-read2 (input-string)
+ (let* ((baddr1 (car ez--next-read-args))
+ (baddr2 (cadr ez--next-read-args)))
+
+ (dotimes (i (length input-string))
+ (let ((char (elt input-string i)))
+ (ez-mem-set-byte (+ baddr1 1 i) char)))
+ (ez-mem-set-byte (+ baddr1 1 (length input-string)) 0)
+
+ (ez--tokenize baddr1 baddr2))
+ 'run)
+
+(defun ez--tokenize (tb-baddr pb-baddr)
+
+ (let ((unfinished t)
+ (token-start 0)
+ (token-end 0)
+ (token-count 0))
+
+ (while unfinished
+ (let ((next-char (ez-mem-ref-byte (+ tb-baddr 1 token-end))))
+ (cond
+ ((eq next-char ?\s)
+ ;; Add token
+ (setq token-end (- token-end 1))
+ (let* ((text (ez-mem-ref-string (+ tb-baddr 1 token-start)
+ (+ tb-baddr 1 token-end)))
+ (dict-entry (ez-lookup-dictionary text)))
+ (setq token-count (+ token-count 1))
+ (ez-mem-set-word (+ pb-baddr 2 (* token-count 4))
+ dict-entry)
+ (ez-mem-set-bytes (+ pb-baddr 2 (* token-count 4) 2)
+ (length text)
+ token-start))
+ (setq token-start (+ token-end 1))
+ (setq token-end token-start))
+
+ ((ez-is-separator char)
+ ;; Add token and separator token
+ )
+ ((eq char 0)
+ (setq unfinished nil))
+ (setq token-end (+ token-end 1)))
+ ))))
+
;; Execution loop
(defun ez-load-and-run (filename)
(defun ez-setup-buffer ()
(with-current-buffer (get-buffer-create "*ez*")
+ (ez-mode)
(let ((inhibit-read-only t))
- (delete-region (point-min) (point-max)))
+ (erase-buffer))
(setq-local scroll-conservatively 1)
(if (markerp ez-input-marker)
(set-marker ez-input-marker (point-max))
(defun ez-enter ()
(interactive)
- (with-current-buffer "*ez*"
- (buffer-substring ez-input-marker (point-max))))
+ (if (not (eq ez-machine-state 'wait-for-input))
+ (error "Z-machine not ready for input."))
+ (let ((input-string
+ (downcase
+ (with-current-buffer "*ez*"
+ (buffer-substring ez-input-marker (point-max))))))
+ (delete-region ez-input-marker (point-max))
+ (ez-print (concat input-string "\n"))
+ (ez-debug-message "\tReceived string \"%s\"" input-string)
+ (ez-op-read2 input-string)
+ (ez-run)))
+
+;; Debugging info
+
+(defun ez-setup-debug-buffer ()
+ (with-current-buffer (get-buffer-create "*ez-debug-trace*")
+ (setq-local buffer-read-only t)
+ (let ((inhibit-read-only t))
+ (erase-buffer)
+ (insert "--- Trace Start ---\n\n"))))
+
+(defun ez-debug-message (&rest strings)
+ (with-current-buffer (get-buffer-create "*ez-debug-trace*")
+ (save-excursion
+ (goto-char (point-max))
+ (let ((inhibit-read-only t))
+ (insert (apply #'format-message strings) "\n")))))
+
+(defun ez-debug-memory ()
+ (interactive)
+ (with-current-buffer (get-buffer-create "*ez-debug-memory*")
+ (setq-local buffer-read-only t)
+ (let ((inhibit-read-only t)
+ (old-point (point)))
+ (if (eq major-mode 'hexl-mode)
+ (hexl-mode-exit))
+ (erase-buffer)
+ (insert ez-memory)
+ (setq-local buffer-undo-list nil)
+ (hexl-mode)
+ (goto-char old-point))))
;; Mode
(if (get-buffer "*ez*")
(switch-to-buffer "*ez*")
(switch-to-buffer "*ez*")
- (ez-mode)
(ez-setup-buffer)
(ez-load-and-run zfile))
"Started EZ.")
(defun ez-debug ()
(interactive)
- (switch-to-buffer "*ez*")
- (ez-mode)
(ez-setup-buffer)
+ (ez-setup-debug-buffer)
(ez-load-and-run "zork1.z3"))
;;; ez.el ends here