read() function to get string input, vm.readKey() to read a key

src/net/torvald/tsvm/VMGUI.kt

@@ -267,7 +267,8 @@ println("");
 print("C:\\\\>");
 
 while (true) {
-    print(String.fromCharCode(vm.readKey()));
+    var s = read();
+    println("String read: " + s + "@");
 }
     """.trimIndent()
 

src/net/torvald/tsvm/VMJSR223Delegate.kt

@@ -21,8 +21,32 @@ class VMJSR223Delegate(val vm: VM) {
         //println("[Nashorn] $s")
         vm.printStream.write((s + '\n').toByteArray())
     }
+    fun println() = print('\n')
 
     fun readKey() = vm.inputStream.read()
+
+    /**
+     * Read series of key inputs until Enter/Return key is pressed
+     */
+    fun read(): String {
+        val sb = StringBuilder()
+        var key: Int
+        do {
+            key = readKey()
+
+            if ((key == 8 && sb.isNotEmpty()) || key in 0x20..0x7E) {
+                this.print("${key.toChar()}")
+            }
+
+            when (key) {
+                8 -> if (sb.isNotEmpty()) sb.deleteCharAt(sb.lastIndex)
+                in 0x20..0x7E -> sb.append(key.toChar())
+            }
+        } while (key != 13 && key != 10)
+        this.println()
+
+        return sb.toString()
+    }
 }
 
 class VMSerialDebugger(val vm: VM) {

src/net/torvald/tsvm/VMRunnerFactory.kt

@@ -72,12 +72,15 @@ object VMRunnerFactory {
 
     private val JS_INIT = """
 function print(s) {
-    vm.print(s)
+    return vm.print(s)
 }
 function println(s) {
-    vm.println(s)
+    return vm.println(s)
 }
-    """
+function read() {
+    return vm.read()
+}
+"""
 }
 
 fun toSingleLine(code: String) = code.replace(Regex("//[^\\n]*"), "").replace('\n', ' ')

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

@@ -81,6 +81,8 @@ abstract class GlassTty(val TEXT_ROWS: Int, val TEXT_COLS: Int) {
             ttyEscArguments.push(ttyEscArguments.pop() * 10 + (newnum.toInt() - 0x30))
         }
 
+        //println("[tty] accepting char $char, state: $ttyEscState")
+
         when (ttyEscState) {
             TTY_ESC_STATE.INITIAL -> {
                 when (char) {

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

@@ -362,8 +362,8 @@ class GraphicsAdapter(val vm: VM, val lcdMode: Boolean = false) : GlassTty(Compa
 
     override fun backspace() {
         val (x, y) = getCursorPos()
-        putChar(x, y, 0x20.toByte())
         setCursorPos(x - 1, y)
+        putChar(x - 1, y, 0x20.toByte())
     }
 
     private lateinit var PRINTSTREAM_INSTANCE: OutputStream
@@ -427,7 +427,7 @@ class GraphicsAdapter(val vm: VM, val lcdMode: Boolean = false) : GlassTty(Compa
                         key = vm.getIO().mmio_read(37L)!!
                     } while (key == (-1).toByte())
 
-                    println("[stdin] key = $key")
+                    //println("[stdin] key = $key")
                     return key.toInt().and(255)
                 }
             }