basic interpreter wip

assets/JS_INIT.js

@@ -0,0 +1,40 @@
+// standard print functions
+function print(s) {
+    vm.print(s);
+}
+function println(s) {
+    if (typeof s == "undefined")
+        vm.print("\n");
+    else
+        vm.println(s);
+}
+function read() {
+    return vm.read();
+}
+// ncurses-like terminal control
+var con = new Object();
+con.getch = function() {
+    return vm.readKey();
+};
+con.move = function(y, x) {
+    print(String.fromCharCode(27,91)+y+";"+x+"H");
+};
+con.addch = function(c) {
+    graphics.putSymbol(c);
+};
+con.mvaddch = function(y, x, c) {
+    move(y, x); addch(c);
+};
+con.getmaxyx = function() {
+    return graphics.getTermDimension();
+};
+con.getyx = function() {
+    return graphics.getCursorYX();
+};
+Object.freeze(con);
+// system management  function
+var sys = new Object();
+sys.maxmem = function() {
+    return vm.peek(-65) | (vm.peek(-66) << 8) | (vm.peek(-67) << 16) | (vm.peek(-68) << 24);
+};
+Object.freeze(sys);

assets/jscon.js

@@ -1,68 +1,70 @@
 println("JS Console");
-var cmdHistory = []; // zeroth element is the oldest
+var _cmdHistory = []; // zeroth element is the oldest
-var cmdHistoryScroll = 0; // 0 for outside-of-buffer, 1 for most recent
+var _cmdHistoryScroll = 0; // 0 for outside-of-buffer, 1 for most recent
 while (true) {
     print("JS> ");
 
-    var cmdbuf = "";
+    var _cmdbuf = "";
 
     while (true) {
-        var key = vm.readKey();
+        var key = con.getch();
 
         // printable chars
         if (key >= 32 && key <= 126) {
-            var s = String.fromCharCode(key);
+            var __sss = String.fromCharCode(key);
-            cmdbuf += s;
+            _cmdbuf += __sss;
-            print(s);
+            print(__sss);
         }
         // backspace
-        else if (key === 8 && cmdbuf.length > 0) {
+        else if (key === 8 && _cmdbuf.length > 0) {
-            cmdbuf = cmdbuf.substring(0, cmdbuf.length - 1);
+            _cmdbuf = _cmdbuf.substring(0, _cmdbuf.length - 1);
             print(String.fromCharCode(key));
         }
         // enter
         else if (key === 10 || key === 13) {
             println();
             try {
-                println(eval(cmdbuf));
+                println(eval(_cmdbuf));
             }
             catch (e) {
                 println(e);
             }
             finally {
-                if (cmdbuf.trim().length > 0)
+                if (_cmdbuf.trim().length > 0)
-                    cmdHistory.push(cmdbuf);
+                    _cmdHistory.push(_cmdbuf);
 
-                cmdHistoryScroll = 0;
+                _cmdHistoryScroll = 0;
                 break;
             }
         }
         // up arrow
-        else if (key === 19 && cmdHistory.length > 0 && cmdHistoryScroll < cmdHistory.length) {
+        else if (key === 19 && _cmdHistory.length > 0 && _cmdHistoryScroll < _cmdHistory.length) {
-            cmdHistoryScroll += 1;
+            _cmdHistoryScroll += 1;
 
             // back the cursor in order to type new cmd
-            for (xx = 0; xx < cmdbuf.length; xx++) print(String.fromCharCode(8));
+            var __xx = 0;
-            cmdbuf = cmdHistory[cmdHistory.length - cmdHistoryScroll];
+            for (__xx = 0; __xx < _cmdbuf.length; __xx++) print(String.fromCharCode(8));
+            _cmdbuf = _cmdHistory[_cmdHistory.length - _cmdHistoryScroll];
             // re-type the new command
-            print(cmdbuf);
+            print(_cmdbuf);
 
         }
         // down arrow
         else if (key === 20) {
-            if (cmdHistoryScroll > 0) {
+            if (_cmdHistoryScroll > 0) {
                 // back the cursor in order to type new cmd
-                for (xx = 0; xx < cmdbuf.length; xx++) print(String.fromCharCode(8));
+                var __xx = 0;
-                cmdbuf = cmdHistory[cmdHistory.length - cmdHistoryScroll];
+                for (__xx = 0; __xx < _cmdbuf.length; __xx++) print(String.fromCharCode(8));
+                _cmdbuf = _cmdHistory[_cmdHistory.length - _cmdHistoryScroll];
                 // re-type the new command
-                print(cmdbuf);
+                print(_cmdbuf);
 
-                cmdHistoryScroll -= 1;
+                _cmdHistoryScroll -= 1;
             }
             else {
                 // back the cursor in order to type new cmd
-                for (xx = 0; xx < cmdbuf.length; xx++) print(String.fromCharCode(8));
+                for (__xx = 0; __xx < _cmdbuf.length; __xx++) print(String.fromCharCode(8));
-                cmdbuf = "";
+                _cmdbuf = "";
             }
         }
     }

assets/tbas/basic.js

@@ -0,0 +1,56 @@
+var vmemsize = 60300;
+var vmemused = 0;
+var cmdbuf = []; // index: line number
+var prompt = "Ok";
+
+var linenumRe = /^[0-9]+ +[^0-9]/;
+
+println("Terran BASIC 1.0  "+vmemsize+" bytes free");
+println(prompt);
+
+var basicFunctions = new Object();
+basicFunctions._basicList = function(v, i, arr) {
+    if (i < 100) print(" ");
+    print(i);
+    print(" ");
+    println(v);
+};
+basicFunctions.list = function(args) {
+    if (args.length == 1) {
+        cmdbuf.forEach(basicFunctions._basicList);
+    }
+    else if (args.length == 2) {
+        if (typeof cmdbuf[args[1]] != "undefined")
+            basicFunctions._basicList(cmdbuf[args[1]], args[1], undefined);
+    }
+    else {
+        var lastIndex = (args[2] === ".") ? cmdbuf.length - 1 : (args[2] | 0);
+        var i = 0;
+        for (i = args[1]; i <= lastIndex; i++) {
+            var cmd = cmdbuf[i];
+            if (typeof cmd != "undefined") {
+                basicFunctions._basicList(cmd, i, cmdbuf);
+            }
+        }
+    }
+};
+
+while (true) {
+    var line = vm.read();
+    line = line.trim();
+
+    if (linenumRe.test(line)) {
+        var i = line.indexOf(" ");
+        cmdbuf[line.slice(0, i)] = line.slice(i + 1, line.length);
+    }
+    else if (line.length > 0) {
+        try {
+            var cmd = line.split(" ");
+            basicFunctions[cmd[0]](cmd);
+        }
+        catch (e) {
+            println("Syntax error");
+        }
+        println(prompt);
+    }
+}

src/net/torvald/tsvm/GraphicsJSR223Delegate.kt

@@ -47,6 +47,35 @@ class GraphicsJSR223Delegate(val vm: VM) {
         }
     }
 
+    fun getPixelDimension(): IntArray {
+        getFirstGPU()?.let { return intArrayOf(it.framebuffer.width, it.framebuffer.height) }
+        return intArrayOf(-1, -1)
+    }
+
+    fun getTermDimension(): IntArray {
+        getFirstGPU()?.let { return intArrayOf(it.TEXT_ROWS, it.TEXT_COLS) }
+        return intArrayOf(-1, -1)
+    }
+
+    fun getCursorYX(): IntArray {
+        getFirstGPU()?.let {
+            val (cx, cy) = it.getCursorPos()
+            return intArrayOf(cy + 1, cx + 1)
+        }
+        return intArrayOf(-1, -1)
+    }
+
+    /**
+     * prints a char as-is; won't interpret them as an escape sequence
+     */
+    fun putSymbol(char: Byte) {
+        getFirstGPU()?.let {
+            val (cx, cy) = it.getCursorPos()
+            it.putChar(cx, cy, char)
+            it.setCursorPos(cx + 1, cy)
+        }
+    }
+
     private fun GraphicsAdapter._loadbulk(fromAddr: Int, toAddr: Int, length: Int) {
         UnsafeHelper.memcpy(
             vm.usermem.ptr + fromAddr,

src/net/torvald/tsvm/VM.kt

@@ -54,7 +54,7 @@ import kotlin.random.Random
  */
 
 class VM(
-    _memsize: Int
+    _memsize: Long
 ) {
 
     val id = java.util.Random().nextInt()

src/net/torvald/tsvm/VMGUI.kt

@@ -16,7 +16,7 @@ import java.io.StringReader
 
 class VMGUI(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter() {
 
-    val vm = VM(8192)
+    val vm = VM(1024.kB())
     lateinit var gpu: GraphicsAdapter
 
     lateinit var batch: SpriteBatch
@@ -52,7 +52,8 @@ class VMGUI(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter()
 
         // TEST PRG
         //val fr = FileReader("./assets/tvdos/command.js")
-        val fr = FileReader("./assets/jscon.js")
+        //val fr = FileReader("./assets/jscon.js")
+        val fr = FileReader("./assets/tbas/basic.js")
         val prg = fr.readText()
         fr.close()
 

src/net/torvald/tsvm/VMJSR223Delegate.kt

@@ -50,11 +50,35 @@ class VMJSR223Delegate(val vm: VM) {
                 in 0x20..0x7E -> sb.append(key.toChar())
             }
         } while (key != 13 && key != 10)
-        this.println()
+        this.print("\n") // printout \n
 
         inputStream.close()
         return sb.toString()
     }
+
+    /**
+     * Read series of key inputs until Enter/Return key is pressed. Backspace will work but any other non-printable
+     * characters (e.g. arrow keys) won't work.
+     */
+    fun readNoEcho(): String {
+        val inputStream = vm.getInputStream()
+        val sb = StringBuilder()
+        var key: Int
+        do {
+            key = inputStream.read()
+
+            when (key) {
+                8 -> if (sb.isNotEmpty()) sb.deleteCharAt(sb.lastIndex)
+                in 0x20..0x7E -> sb.append(key.toChar())
+            }
+        } while (key != 13 && key != 10)
+        this.println() // printout \n
+
+        inputStream.close()
+        return sb.toString()
+    }
+
+
 }
 
 class VMSerialDebugger(val vm: VM) {

src/net/torvald/tsvm/VMRunnerFactory.kt

@@ -1,5 +1,6 @@
 package net.torvald.tsvm
 
+import java.io.FileInputStream
 import java.io.FileReader
 import javax.script.Compilable
 import javax.script.ScriptContext
@@ -56,13 +57,16 @@ object VMRunnerFactory {
                         bind.put("serial", VMSerialDebugger(vm))
 
                         if (extension == "js") {
-                            engine.eval(toSingleLine(JS_INIT), context)
+                            val fr = FileReader("./assets/JS_INIT.js")
+                            val prg = fr.readText()
+                            fr.close()
+                            engine.eval(toSingleLine(prg), context)
                         }
                     }
 
                     override suspend fun executeCommand(command: String) {
                         //(engine as Compilable).compile(command).eval(context) // compiling does not work with bindings in kts
-                        engine.eval(command, context)
+                        engine.eval("\"use strict\";{$command}", context)
                     }
                 }
             }
@@ -70,20 +74,6 @@ object VMRunnerFactory {
         }
     }
 
-    private val JS_INIT = """
-function print(s) {
-    vm.print(s);
-}
-function println(s) {
-    if (typeof s == "undefined")
-        vm.print("\n");
-    else
-        vm.println(s);
-}
-function read() {
-    return vm.read();
-}
-"""
 }
 
 fun toSingleLine(code: String) = code.replace(Regex("//[^\\n]*"), "").replace('\n', ' ')

src/net/torvald/tsvm/peripheral/GraphicsAdapter.kt

@@ -336,6 +336,18 @@ class GraphicsAdapter(val vm: VM, val lcdMode: Boolean = false) : GlassTty(Compa
     }
 
     override fun sgrTwoArg(arg1: Int, arg2: Int) {
+        /*
+        Color table for default palette
+
+        Black   240
+        Red     160
+        Green   30
+        Yellow  230
+        Blue    19
+        Magenta 199
+        Cyan    74
+        White   254
+         */
         TODO("Not yet implemented")
     }
 
@@ -347,7 +359,7 @@ class GraphicsAdapter(val vm: VM, val lcdMode: Boolean = false) : GlassTty(Compa
      * @param arg1 y-position (row)
      * @param arg2 x-position (column) */
     override fun cursorXY(arg1: Int, arg2: Int) {
-        setCursorPos(arg2, arg1)
+        setCursorPos(arg2 - 1, arg1 - 1)
     }
 
     override fun ringBell() {

terranmon.txt

@@ -56,6 +56,11 @@ MMIO
     usually unnecessary as such action must be automatically managed via LibGDX
     input processing.
     Stores ASCII code representing the character, plus:
+   (1..26: Ctrl+[alph])
+    3 : Ctrl+C
+    4 : Ctrl+D
+    8 : Backspace
+   (13: Return)
     19: Up arrow
     20: Down arrow
     21: Left arrow