X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=ez.git;a=blobdiff_plain;f=ez.el;h=af348a982f49420db40b407bda96f4819116140c;hp=e899ab46493c68f693418ce9e0baa0331796fb6f;hb=HEAD;hpb=9d1263da3e1499040fe258ea8dea1c60ae7ccf6a

diff --git a/ez.el b/ez.el
index e899ab4..a6f1f9c 100644
--- a/ez.el
+++ b/ez.el
@@ -1,8 +1,8 @@
 ;;; 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
@@ -26,6 +26,13 @@
 
 ;;; Commentary:
 
+;; There are many Z-machine interpreters, but this one is mine.
+;; It only capable of interpreting the subset of Z-code necessary
+;; to run the first Zork game in z3 format.
+;;
+;; It is based entirely on the description of the Z-machine contained
+;; Marnix Klooster's wonderful document, "The Z-machine And How to Emulate It."
+
 ;;; Code:
 
 ;; Utility functions
@@ -41,6 +48,11 @@
 (defun ez-decode-signed-word (w)
   (ez-decode-signed-bits w 16))
 
+(defun ez-decode-signed-operand (operand operand-type)
+  (if (eq operand-type 'b)
+      (ez-decode-signed-byte operand)
+    (ez-decode-signed-word operand)))
+
 (defun binformat (n &optional s)
   (unless s
     (setq s ""))
@@ -50,6 +62,14 @@
         new-s
       (binformat d new-s))))
 
+(defun ez-list-to-string-hex (l)
+  (concat "("
+          (when l
+            (concat
+             (format "%x" (car l))
+             (apply 'concat (mapcar (lambda (n) (format " %x" n)) (cdr l)))))
+          ")"))
+
 ;; Memory
 
 (defvar ez-memory nil
@@ -59,20 +79,38 @@
 
 (defvar ez-start-pc nil)
 (defvar ez-himem-base nil)
-(defvar ez-dict-addr nil)
+(defvar ez-dict-base nil)
 (defvar ez-objtab-addr nil)
 (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))
@@ -80,6 +118,9 @@
     (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))
@@ -93,28 +134,25 @@
   "Load story file into memory."
   (with-temp-buffer
     (insert-file-contents-literally filename)
-    (setq ez-memory (encode-coding-string (buffer-string) 'raw-text))))
+    (setq ez-memory (encode-coding-string (buffer-string) 'raw-text)))
+  'done)
 
 ;; Global variables
 
 (defun ez-get-global-var (gvar)
-  (ez-mem-ref-word (+ (* 2 gvar) (ez-mem-ref-word ez-globalvartab-addr))))
+  (if (> gvar 239)
+      (error "Invalid global variable %d" gvar))
+  (let ((val
+         (ez-mem-ref-word (+ (* 2 gvar) ez-globalvartab-addr))))
+    (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-mem-ref-word ez-globalvartab-addr)) val))
+  (ez-mem-set-word (+ (* 2 gvar) ez-globalvartab-addr) val)
+  (ez-debug-message "\tSet global variabl %x to %x" gvar val))
 
 ;; Object tree
 
-(defun ez-make-obj (&optional name attribs props parent first-child next-sibling)
-    (list name attribs props parent first-child next-sibling))
-
-(defun ez-obj-name (obj) (elt obj 0))
-(defun ez-obj-attribs (obj) (elt obj 1))
-(defun ez-obj-props (obj) (elt obj 2))
-(defun ez-obj-parent (obj) (elt obj 3))
-(defun ez-obj-first-child (obj) (elt obj 4))
-(defun ez-obj-next-sibling (obj) (elt obj 5))
-
 (defvar ez-property-defaults nil)
 
 (defun ez-load-property-defaults ()
@@ -122,21 +160,124 @@
   (dotimes (i 31)
     (aset ez-property-defaults i (aref ez-memory (+ ez-objtab-addr (* 2 i))))))
 
-(defun ez-get-obj (obj-id)
-  (let ((addr (+ ez-objtab-addr
-                 (* 2 31)
-                 (* 9 (- obj-id 1)))))
-    (list
-     obj-id
-     (ez-mem-ref-byte (+ addr 4))
-     (ez-mem-ref-byte (+ addr 5))
-     (ez-mem-ref-byte (+ addr 6))
-     (ez-mem-ref-word (+ addr 7))
-     (let ((plist-addr (ez-mem-ref-word (+ addr 7))))
-       (if (> (ez-mem-ref-byte plist-addr) 0)
-           (ez-get-zstring (+ 1 plist-addr))
-         "")))))
-
+(defun ez-get-obj-addr (obj)
+  (+ ez-objtab-addr (* 2 31) (* 9 (- obj 1))))
+
+(defun ez-get-obj-parent (obj)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-ref-byte (+ addr 4))))
+
+(defun ez-set-obj-parent (obj new-parent)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-set-byte (+ addr 4) new-parent)))
+
+(defun ez-get-obj-sibling (obj)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-ref-byte (+ addr 5))))
+
+(defun ez-set-obj-sibling (obj new-sibling)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-set-byte (+ addr 5) new-sibling)))
+
+(defun ez-get-obj-child (obj)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-ref-byte (+ addr 6))))
+
+(defun ez-set-obj-child (obj new-child)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-set-byte (+ addr 6) new-child)))
+
+(defun ez-get-obj-plist-addr (obj)
+  (let ((addr (ez-get-obj-addr obj)))
+    (ez-mem-ref-word (+ addr 7))))
+
+(defun ez-get-obj-name (obj)
+  (let ((plist-addr (ez-get-obj-plist-addr obj)))
+    (if (> (ez-mem-ref-byte plist-addr) 0)
+        (ez-get-zstring (+ 1 (ez-get-obj-plist-addr obj)))
+      nil)))
+
+(defun ez-get-prop-default (prop)
+  (ez-mem-ref-word (+ ez-objtab-addr (* 2 (+ 1 prop)))))
+
+(defun ez-get-prop-len (prop-size-byte)
+  (lsh prop-size-byte -5))
+
+(defun ez-get-prop-num (prop-size-byte)
+  (logand #b00011111 prop-size-byte))
+
+(defun ez-get-obj-prop-addr (obj prop)
+  (let* ((plist-addr (ez-get-obj-plist-addr obj))
+         (prop-addr (+ plist-addr 1 (* 2 (ez-mem-ref-byte plist-addr))))
+         (size-byte (ez-mem-ref-byte prop-addr)))
+    (while (not (or (= size-byte 0)
+                    (= prop (ez-get-prop-num size-byte))))
+      (setq prop-addr (+ prop-addr (ez-get-prop-len size-byte) 2)
+            size-byte (ez-mem-ref-byte prop-addr)))
+    prop-addr))
+
+(defun ez-get-obj-prop (obj prop)
+  (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
+         (size-byte (ez-mem-ref-byte prop-addr)))
+    (if (= size-byte 0)
+        (ez-get-prop-default prop)
+      (let ((prop-len (ez-get-prop-len size-byte))
+            (data-addr (+ prop-addr 1)))
+        (cond
+         ((= prop-len 0)
+          (ez-mem-ref-byte data-addr))
+         ((>= prop-len 1)
+          (ez-mem-ref-word data-addr)))))))
+
+(defun ez-set-obj-prop (obj prop value)
+  (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
+         (size-byte (ez-mem-ref-byte prop-addr)))
+    (cond
+     ((= size-byte 0)
+      (error "Tried to set non-existant property"))
+     ((= (ez-get-prop-len size-byte) 1)
+      (ez-mem-set-byte (+ prop-addr 1) value))
+     (t
+      (ez-mem-set-word (+ prop-addr 1) value)))))
+
+(defun ez-get-obj-attr (obj attr)
+  (let* ((byte-num (/ attr 8))
+         (bit-num (mod attr 8))
+         (bit-mask (lsh 1 (- 7 bit-num))))
+    (if (> (logand bit-mask (ez-mem-ref-byte (+ (ez-get-obj-addr obj) byte-num))) 0)
+        1
+      0)))
+
+(defun ez-set-obj-attr (obj attr val)
+  (let* ((byte-num (/ attr 8))
+         (bit-num (mod attr 8))
+         (bit-mask (lsh 1 (- 7 bit-num)))
+         (byte-addr (+ (ez-get-obj-addr obj) byte-num))
+         (byte (ez-mem-ref-byte byte-addr))
+         (current-set (> (logand bit-mask byte) 0)))
+    (if (or (and current-set (= val 0))
+            (and (not current-set) (> val 0)))
+        (ez-mem-set-byte byte-addr (logxor byte bit-mask)))))
+
+
+(defun ez-remove-obj (obj)
+  (let ((parent (ez-get-obj-parent obj))
+        (sibling (ez-get-obj-sibling obj)))
+    (unless (= parent 0)
+      (let ((child (ez-get-obj-child parent)))
+        (if (= child obj)
+            (ez-set-obj-child parent sibling)
+          (while (not (= obj (ez-get-obj-sibling child)))
+            (setq child (ez-get-obj-sibling child)))
+          (ez-set-obj-sibling child (ez-get-obj-sibling obj))))
+      (ez-set-obj-parent obj 0))
+    (ez-set-obj-sibling obj 0)))
+
+(defun ez-insert-obj (obj new-parent)
+  (ez-remove-obj obj)
+  (unless (= new-parent 0)
+    (ez-set-obj-sibling obj (ez-get-obj-child new-parent))
+    (ez-set-obj-child new-parent obj)))
 
 ;; Z-strings
 
@@ -154,44 +295,139 @@
         (logand (lsh word -5) #b11111)
         (logand word #b11111)))
 
-(defun ez-get-zstring-chars (base-addr)
+(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)
-        (not-done t))
+        (not-done t)
+        (word-count 0))
     (while not-done
       (let ((components (ez-parse-zstring-word (ez-mem-ref-word addr))))
         (setq chars (append chars (cdr components)))
         (setq addr (+ addr 2))
+        (setq word-count (+ word-count 1))
         (when (= (car components) 1)
           (setq not-done nil))))
-    chars))
+    (cons word-count chars)))
+
+(defun ez-get-zstring-and-length (base-addr)
+  (let* ((word-count-and-chars (ez-get-zstring-chars-and-length base-addr))
+         (word-count (car word-count-and-chars))
+         (chars (cdr word-count-and-chars))
+         (cur 0)
+         (lock 0)
+         (s ""))
+    (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)
-  (let ((chars (ez-get-zstring-chars base-addr))
-        (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 (ez-get-zstring abbrev-addr))))
-        (setq abbrev-char nil))
-       ((memq char '(1 2 3)) ;Abbreviation
-        (setq abbrev-char char))
-       ((= char 4)
-        (setq cur (mod (+ cur 1) 2)))
-       ((= char 5)
-        (setq cur (mod (+ 2 (- cur 1)) 2)))
-       (t 
-        (setq s (concat s (substring (elt ez-zstring-alphabets cur)
-                                     char (+ char 1))))
-        (setq cur lock))))
-    s))
-
+  (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
 
@@ -214,20 +450,25 @@
 
 (defun ez-routine-stack-push (val)
   (let ((frame (car ez-call-stack)))
+    (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)))
+    (ez-debug-message "\tPopped %x from stack" rs-head)
     rs-head))
 
 (defun ez-get-local-var (lvar)
-  (let ((frame (car ez-call-stack)))
-    (aref (elt frame 2) (- lvar 1))))
+  (let* ((frame (car ez-call-stack))
+         (val (aref (elt frame 2) (- lvar 1))))
+    (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)))
+    (ez-debug-message "\tSet local variable %x to %x" lvar val)
     (aset (elt frame 2) (- lvar 1) val)))
 
 (defun ez-get-pc ()
@@ -275,9 +516,7 @@
 (defun ez-execute-instr ()
   (let ((instr-pc (ez-get-pc))
         (opbyte (ez-read-pc-byte-and-inc))
-        (optype)
-        (opcode nil)
-        (operands))
+        (optype) (opcode) (operands))
     (cond
      ((<= #x0 opbyte #x1f)
       (setq optype '2op
@@ -320,9 +559,15 @@
             operand-types '(w)))
      ((<= #xB0 opbyte #xBF)
       (setq optype '0op
-            opcode (- opbyte #xb0)))
+            opcode (- opbyte #xb0)
+            operands '()
+            operand-types '()))
      ((<= #xC0 opbyte #xDF)
-      (error "Unsupported op" opbyte))
+      (setq optype '2op
+            opcode (- opbyte #xc0))
+      (let ((operands-and-types (ez-read-var-operands-and-inc)))
+        (setq operands (car operands-and-types)
+              operand-types (cdr operands-and-types))))
      ((<= #xE0 opbyte #xFF)
       (setq optype 'var
             opcode (- opbyte #xe0))
@@ -331,32 +576,32 @@
               operand-types (cdr operands-and-types)))))
     (let ((table-row (assoc (list optype opcode) ez-op-table)))
       (unless table-row
-        (error "Unsupported op" optype opcode))
+        (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"
-                 instr-pc optype opcode mnemonic operands))
+        (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-read-var-operands-and-inc ()
   (let* ((type-byte (ez-read-pc-byte-and-inc))
-         (bleh (message (binformat type-byte)))
          (types (let ((type1 (lsh type-byte -6)))
                   (if (= type1 #b11)
                       nil
                     (cons type1
-                          (let ((type2 (lsh (logand #b110000 type-byte) -4)))
+                          (let ((type2 (mod (lsh type-byte -4) 4)))
                             (if (= type2 #b11)
                                 nil
                               (cons type2
-                                    (let ((type3 (lsh (logand #b1100 type-byte) -2)))
+                                    (let ((type3 (mod (lsh type-byte -2) 4)))
                                       (if (= type3 #b11)
                                           nil
                                         (cons type3
-                                              (let ((type4 (logand #b11)))
+                                              (let ((type4 (mod type-byte 4)))
                                                 (if (= type4 #b11)
                                                     nil
-                                                  (list type4)))))))))))))
-         (operands nil))
+                                                  (list type4))))))))))))))
     (cons
      (mapcar
       (lambda (type)
@@ -377,7 +622,7 @@
 (defun ez-do-branch (branch)
   (let* ((branch-byte (ez-read-pc-byte-and-inc))
          (invert (= 0 (logand branch-byte #b10000000)))
-         (single-byte (= 1 (logand branch-byte #b01000000)))
+         (single-byte (> (logand branch-byte #b01000000) 0))
          (offset
           (if single-byte
               (logand branch-byte #b00111111)
@@ -387,13 +632,15 @@
               (if pos
                   val
                 (- val 8192))))))
-    (cond
-     ((= offset 0)
-      (ez-op-rfalse))
-     ((= offset 1)
-      (ez-op-rtrue))
-     (t
-      (ez-set-pc (+ (ez-get-pc) offset -2))))))
+    (if (or (and branch (not invert))
+            (and (not branch) invert))
+        (cond
+         ((= offset 0)
+          (ez-op-rfalse))
+         ((= offset 1)
+          (ez-op-rtrue))
+         (t
+          (ez-set-pc (+ (ez-get-pc) offset -2)))))))
 
 ;; Operations
 
@@ -401,12 +648,24 @@
   '(((0op #x00) rtrue ez-op-rtrue)
     ((0op #x01) rfalse ez-op-rfalse)
     ((1op #x00) jz ez-op-jz)
+    ((1op #x05) inc ez-op-inc)
+    ((1op #x06) dec ez-op-dec)
     ((1op #x0B) ret ez-op-ret)
+    ((0op #x08) ret_pulled ez-op-ret-pulled)
     ((1op #x0C) jump ez-op-jump)
+    ((2op #x05) inc_jg ez-op-inc-jg)
+    ((2op #x04) dec_jg ez-op-dec-jg)
     ((2op #x0D) store ez-op-store)
     ((1op #x0E) load ez-op-load)
     ((var #x01) storew ez-op-storew)
+    ((2op #x0F) loadw ez-op-loadw)
+    ((var #x02) storeb ez-op-storeb)
+    ((2op #x10) loadb ez-op-loadb)
     ((2op #x01) je ez-op-je)
+    ((2op #x02) jl ez-op-jl)
+    ((2op #x03) jg ez-op-jg)
+    ((2op #x06) jin ez-op-jin)
+    ((2op #x07) test ez-op-test)
     ((2op #x08) or ez-op-or)
     ((2op #x09) and ez-op-and)
     ((2op #x14) add ez-op-add)
@@ -414,82 +673,173 @@
     ((2op #x16) mul ez-op-mul)
     ((2op #x17) div ez-op-div)
     ((2op #x18) mod ez-op-mod)
-    ((var #x00) call_fv ez-op-callf)))
+    ((var #x00) call_fv ez-op-callfv)
+    ((1op #x01) get_sibling ez-op-get-sibling)
+    ((1op #x02) get_child ez-op-get-child)
+    ((1op #x03) get_parent ez-op-get-parent)
+    ((2op #x0A) test_attr ez-op-test-attr)
+    ((2op #x0B) set_attr ez-op-set-attr)
+    ((2op #x0C) clear_attr ez-op-clear-attr)
+    ((1op #x09) remove_obj ez-op-remove-obj)
+    ((2op #x0E) insert_obj ez-op-insert-obj)
+    ((var #x03) put_prop ez-op-put-prop)
+    ((2op #x11) get_prop ez-op-get-prop)
+    ((0op #x02) print ez-op-print)
+    ((0op #x0B) new_line ez-op-new-line)
+    ((var #x06) print_num ez-op-print-num)
+    ((var #x05) print_char ez-op-print-char)
+    ((1op #x0A) print_obj ez-op-print-obj)
+    ((var #x04) read ez-op-read)))
 
 (defun ez-op-ret (operands &optional operand-types)
   (let ((retval (car operands)))
+    (ez-debug-message "\tReturning value %x" retval)
     (ez-pop-call-stack-frame)
     (ez-set-var (ez-read-pc-byte-and-inc) retval))
-  t)
+  'run)
+
+(defun ez-op-ret-pulled (operands operand-types)
+  (let ((retval (ez-routine-stack-pop)))
+    (ez-debug-message "\tReturning value %x" retval)
+    (ez-op-ret (list retval)))
+  'run)
 
 (defun ez-op-rtrue (&optional operands operand-types)
-  (ez-op-ret (list 1)))
+  (ez-op-ret (list 1))
+  'run)
 
 (defun ez-op-rfalse (&optional operands operand-types)
-  (ez-op-ret (list 0)))
+  (ez-op-ret (list 0))
+  'run)
 
 (defun ez-op-jz (operands operand-types)
   (ez-do-branch (= (car operands) 0))
-  t)
+  'run)
 
 (defun ez-op-je (operands operand-types)
   (ez-do-branch (memq (car operands) (cdr operands)))
-  t)
+  'run)
+
+(defun ez-op-jg (operands operand-types)
+  (let ((s1 (ez-decode-signed-operand (car operands) (car operand-types)))
+        (s2 (ez-decode-signed-operand (cadr operands) (cadr operand-types))))
+    (ez-do-branch (> s1 s2)))
+  'run)
+
+(defun ez-op-jl (operands operand-types)
+  (let ((s1 (ez-decode-signed-operand (car operands) (car operand-types)))
+        (s2 (ez-decode-signed-operand (cadr operands) (cadr operand-types))))
+    (ez-do-branch (< s1 s2)))
+  'run)
+
+(defun ez-op-inc-jg (operands operand-types)
+  (let ((var (car operands)))
+    (ez-op-inc (list var))
+    (ez-op-jg (cons (ez-get-var var) (cdr operands)) (cons 'w (cdr operand-types))))
+  'run)
+
+(defun ez-op-dec-jl (operands operand-types)
+  (let ((var (car operands)))
+    (ez-op-dec (list var))
+    (ez-op-jl (cons (ez-get-var var) (cdr operands)) (cons 'w (cdr operand-types))))
+  'run)
+
+(defun ez-op-jin (operands operand-types)
+  (let ((obj (car operands))
+        (n (cadr operands)))
+    (ez-do-branch (or (= n 0)
+                      (= n (ez-get-obj-parent obj)))))
+  'run)
+
+(defun ez-op-test (operands operand-types)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-do-branch (= (logand a b) b)))
+  'run)
 
 (defun ez-op-jump (operands operand-types)
   (let ((offset (if (eq (car operand-types) 'b)
                     (ez-decode-signed-byte (car operands))
                   (ez-decode-signed-word (car operands)))))
     (ez-set-pc (+ (ez-get-pc) offset -2)))
-  t)
+  'run)
+
+(defun ez-op-inc (operands &optional operand-types)
+  (let ((var (car operands)))
+    (ez-set-var var (mod (+ 1 (ez-get-var var)) #x10000)))
+  'run)
+
+(defun ez-op-dec (operands &optional operand-types)
+  (let ((var (car operands)))
+    (ez-set-var var (mod (+ (ez-get-var var) 1) #x10000)))
+  'run)
 
 (defun ez-op-store (operands operand-types)
   (let ((var (car operands))
         (a (cadr operands)))
     (ez-set-var var a))
-  t)
+  'run)
 
 (defun ez-op-load (operands operand-types)
   (let ((var (car operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (ez-get-var var)))
-  t)
+  'run)
 
 (defun ez-op-storew (operands operand-types)
   (let ((baddr (car operands))
         (n (cadr operands))
         (a (caddr operands)))
     (ez-mem-set-word (+ baddr (* 2 n)) a))
-  t)
+  'run)
+
+(defun ez-op-loadw (operands operand-types)
+  (let ((baddr (car operands))
+        (n (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (ez-mem-ref-word (+ baddr (* 2 n)))))
+  'run)
+
+(defun ez-op-storeb (operands operand-types)
+  (let ((baddr (car operands))
+        (n (cadr operands))
+        (a (caddr operands)))
+    (ez-mem-set-byte (+ baddr n) a))
+  'run)
+
+(defun ez-op-loadb (operands operand-types)
+  (let ((baddr (car operands))
+        (n (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (ez-mem-ref-byte (+ baddr n))))
+  'run)
 
 (defun ez-op-and (operands operand-types)
   (let ((a (car operands))
         (b (cadr operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (logand a b)))
-  t)
+  'run)
 
 (defun ez-op-or (operands operand-types)
   (let ((a (car operands))
         (b (cadr operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (logior a b)))
-  t)
+  'run)
 
 (defun ez-op-add (operands operand-types)
   (let ((a (car operands))
         (b (cadr operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ a b) #x10000)))
-  t)
+  'run)
 
 (defun ez-op-sub (operands operand-types)
   (let ((a (car operands))
         (b (cadr operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ (- a b) #x10000) #x10000)))
-  t)
+  'run)
 
 (defun ez-op-mul (a b)
   (let ((a (car operands))
         (b (cadr operands)))
     (ez-set-var (ez-read-pc-byte-and-inc) (mod (* a b) #x10000)))
-  t)
+  'run)
 
 (defun ez-op-div (a b)
   (error "Not implemented"))
@@ -497,54 +847,272 @@
 (defun ez-op-mod (a b)
   (error "Not implemented"))
 
-(defun ez-op-callf (operands operand-types)
+(defun ez-op-callfv (operands operand-types)
   (let* ((raddr (car operands))
          (call-operands (cdr operands))
          (r (* 2 raddr))
          (L (ez-mem-ref-byte r))
          (n (length call-operands))
          (new-pc (+ r 1 (* L 2))))
-    (ez-add-call-stack-frame new-pc)
-    (dotimes (i L)
-      (if (< i n)
-          (ez-set-local-var (+ i 1) (elt call-operands i))
-        (ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i)))))))
-  t)
-
-;; Main
-
-(defun ez-run (filename)
+    (if (= raddr 0)
+        (ez-set-var (ez-read-pc-byte-and-inc) 0) ; Simply return 0
+      (ez-add-call-stack-frame new-pc)
+      (dotimes (i L)
+        (if (< i n)
+            (ez-set-local-var (+ i 1) (elt call-operands i))
+          (ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i))))))))
+  'run)
+
+(defun ez-op-test-attr (operands operand-types)
+  (let ((obj (car operands))
+        (attr (cadr operands)))
+    (ez-do-branch (= 1 (ez-get-obj-attr obj attr)))
+    'run))
+
+(defun ez-op-set-attr (operands operand-types)
+  (let ((obj (car operands))
+        (attr (cadr operands)))
+    (ez-set-obj-attr obj attr 1))
+  'run)
+
+(defun ez-op-clear-attr (operands operand-types)
+  (let ((obj (car operands))
+        (attr (cadr operands)))
+    (ez-set-obj-attr obj attr 0))
+  'run)
+
+(defun ez-op-get-sibling (operands operand-types)
+  (let ((sib (ez-get-obj-sibling (car operands))))
+    (ez-set-var (ez-read-pc-byte-and-inc) sib)
+    (ez-do-branch (> sib 0)))
+  'run)
+
+(defun ez-op-get-child (operands operand-types)
+  (let ((child (ez-get-obj-child (car operands))))
+    (ez-set-var (ez-read-pc-byte-and-inc) child)
+    (ez-do-branch (> child 0)))
+  'run)
+
+(defun ez-op-get-parent (operands operand-types)
+  (let ((parent (ez-get-obj-parent (car operands))))
+    (ez-set-var (ez-read-pc-byte-and-inc) parent))
+  'run)
+
+(defun ez-op-remove-obj (operands operand-types)
+  (let ((obj (car operands)))
+    (ez-remove-obj obj))
+  'run)
+
+(defun ez-op-insert-obj (operands operand-types)
+  (let ((obj1 (car operands))
+        (obj2 (cadr operands)))
+    (ez-insert-obj obj1 obj2))
+  'run)
+
+(defun ez-op-put-prop (operands operand-types)
+  (let* ((obj (car operands))
+         (prop (cadr operands))
+         (a (caddr operands)))
+    (ez-set-obj-prop obj prop a))
+  'run)
+
+(defun ez-op-get-prop (operands operand-types)
+  (let* ((obj (car operands))
+         (prop (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc)
+                (ez-get-obj-prop obj prop)))
+  'run)
+
+(defun ez-op-print (operands operand-types)
+  (let* ((word-count-and-string (ez-get-zstring-and-length (ez-get-pc)))
+         (word-count (car word-count-and-string))
+         (string (cdr word-count-and-string)))
+    (ez-print string)
+    (ez-increment-pc (* 2 word-count)))
+  'run)
+
+(defun ez-op-new-line (operands operand-types)
+  (ez-print "\n")
+  'run)
+
+(defun ez-op-print-num (operands operand-types)
+  (let ((s (ez-decode-signed-operand (car operands) (car operand-types))))
+    (ez-print (number-to-string s)))
+  'run)
+
+(defun ez-op-print-char (operands operand-types)
+  (let ((c (car operands)))
+    (ez-print (string c)))
+  'run)
+
+(defun ez-op-print-obj (operands operand-types)
+  (let ((obj (car operands)))
+    (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)
   (ez-load-file filename)
   (ez-parse-header)
   (setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
 
-  (while (ez-execute-inst)))
-
-;; Scratch
-
-(ez-load-file "zork1.z3")
-(ez-parse-header)
-(setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
-(ez-execute-instr)
-
-(binformat #x97)
-"10010111"
-
-
-ez-call-stack
-((28281 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
-
-((22049 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
-
-
-
-
-
-
-
-
-
-
-
+  (ez-run))
+
+(defvar ez-machine-state nil
+  "Identifies the current executation state of the Z-machine.")
+
+(defun ez-run ()
+  (setq ez-machine-state 'run)
+  (while (eq ez-machine-state 'run)
+    (setq ez-machine-state (ez-execute-instr))))
+
+;;; Buffer and I/O
+;;
+
+(defvar ez-input-marker nil
+  "Marker for input position in buffer.")
+
+(defun ez-setup-buffer ()
+  (with-current-buffer (get-buffer-create "*ez*")
+    (ez-mode)
+    (let ((inhibit-read-only t))
+      (erase-buffer))
+    (setq-local scroll-conservatively 1)
+    (if (markerp ez-input-marker)
+        (set-marker ez-input-marker (point-max))
+      (setq ez-input-marker (point-max-marker)))
+    (goto-char (point-max))))
+
+
+(defun ez-print (string)
+  (with-current-buffer "*ez*"
+    (save-excursion
+      (goto-char ez-input-marker)
+      (insert-before-markers string))))
+
+(defun ez-enter ()
+  (interactive)
+  (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
+
+(defvar ez-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd "RET") 'ez-enter)
+    map))
+
+(define-derived-mode ez-mode text-mode "ez"
+  "Major mode for EZ.")
+
+(when (fboundp 'evil-set-initial-state)
+  (evil-set-initial-state 'ez-mode 'insert))
+
+(defun ez (zfile)
+  (interactive "fEnter name of z3 story file: ")
+  (if (get-buffer "*ez*")
+      (switch-to-buffer "*ez*")
+    (switch-to-buffer "*ez*")
+    (ez-setup-buffer)
+    (ez-load-and-run zfile))
+  "Started EZ.")
+
+(defun ez-debug ()
+  (interactive)
+  (ez-setup-buffer)
+  (ez-setup-debug-buffer)
+  (ez-load-and-run "zork1.z3"))
 
 ;;; ez.el ends here