Added "NEW" command to demo BASIC interpreter. Still not very useful, but we

now have some of the basic framework in place to implement a minimalistic
interpreter.


git-svn-id: https://shellinabox.googlecode.com/svn/trunk@102 0da03de8-d603-11dd-86c2-0f8696b7b6f9

config.h

@@ -95,7 +95,7 @@
 #define STDC_HEADERS 1
 
 /* Most recent revision number in the version control system */
-#define VCS_REVISION "101"
+#define VCS_REVISION "102"
 
 /* Version number of package */
 #define VERSION "2.5"

configure

@@ -2056,7 +2056,7 @@ ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
-VCS_REVISION=101
+VCS_REVISION=102
 
 
 cat >>confdefs.h <<_ACEOF

configure.ac

@@ -2,7 +2,7 @@ AC_PREREQ(2.57)
 
 dnl This is the one location where the authoritative version number is stored
 AC_INIT(shellinabox, 2.5, markus@shellinabox.com)
-VCS_REVISION=101
+VCS_REVISION=102
 AC_SUBST(VCS_REVISION)
 AC_DEFINE_UNQUOTED(VCS_REVISION, "${VCS_REVISION}",
                    [Most recent revision number in the version control system])

demo/demo.js

@@ -69,8 +69,8 @@
 // #define STATE_READLINE 3
 // #define STATE_COMMAND  4
 // #define STATE_EVAL     5
-// #define STATE_RUN      6
+// #define STATE_EXEC     6
-// #define STATE_EXEC     7
+// #define STATE_NEW_Y_N  7
 
 function extend(subClass, baseClass) {
   function inheritance() { }
@@ -87,6 +87,16 @@ function Demo(container) {
 extend(Demo, VT100);
 
 Demo.prototype.keysPressed = function(ch) {
+  if (this.state == 6 /* STATE_EXEC */) {
+    for (var i = 0; i < ch.length; i++) {
+      var c       = ch.charAt(i);
+      if (c == '\u0003') {
+        this.keys = '';
+        this.error('Interrupted');
+        return;
+      }
+    }
+  }
   this.keys      += ch;
   this.gotoState(this.state);
 };
@@ -97,7 +107,7 @@ Demo.prototype.gotoState = function(state, tmo) {
     if (!tmo) {
       tmo          = 1;
     }
-    this.timer = setTimeout(function(demo) {
+    this.nextTimer = setTimeout(function(demo) {
                                   return function() {
                                     demo.demo();
                                   };
@@ -107,35 +117,31 @@ Demo.prototype.gotoState = function(state, tmo) {
 
 Demo.prototype.demo = function() {
   var done                  = false;
+  this.nextTimer            = undefined;
   while (!done) {
     var state               = this.state;
     this.state              = 0 /* STATE_IDLE */;
     switch (state) {
     case 1 /* STATE_INIT */:
-      this.doInit();
+      done                  = this.doInit();
       break;
     case 2 /* STATE_PROMPT */:
-      this.doPrompt();
+      done                  = this.doPrompt();
       break;
     case 3 /* STATE_READLINE */:
-      this.doReadLine();
+      done                  = this.doReadLine();
-      if (this.state == 3 /* STATE_READLINE */) {
-        done                = true;
-      }
       break;
     case 4 /* STATE_COMMAND */:
-      this.doCommand();
+      done                  = this.doCommand();
       break;
     case 5 /* STATE_EVAL */:
-      this.doEval();
+      done                  = this.doEval();
       break;
-    case 6 /* STATE_RUN */:
+    case 6 /* STATE_EXEC */:
-      this.doRun();
+      done                  = this.doExec();
       break;
-    case 7 /* STATE_EXEC */:
+    case 7 /* STATE_NEW_Y_N */:
-      if (this.doExec()) {
+      done                  = this.doNewYN();
-        return;
-      }
       break;
     case 0 /* STATE_IDLE */:
     default:
@@ -143,15 +149,22 @@ Demo.prototype.demo = function() {
       break;
     }
   }
-  this.timer   = undefined;
+  this.timer                = this.nextTimer;
+  this.nextTimer            = undefined;
 };
 
+Demo.prototype.ok = function() {
+  this.vt100('OK\r\n');
+  this.gotoState(2 /* STATE_PROMPT */);
+}
+
 Demo.prototype.error = function(msg) {
   if (msg == undefined) {
     msg                 = 'Syntax Error';
   }
   this.vt100('\u0007? ' + msg + '\r\n');
   this.gotoState(2 /* STATE_PROMPT */);
+  this.currentLineIndex = -1;
 };
 
 Demo.prototype.doInit = function() {
@@ -170,6 +183,7 @@ Demo.prototype.doInit = function() {
     'Type HELP for a list of commands.\r\n' +
     '\r\n');
   this.gotoState(2 /* STATE_PROMPT */);
+  return false;
 };
 
 Demo.prototype.doPrompt = function() {
@@ -178,6 +192,7 @@ Demo.prototype.doPrompt = function() {
   this.currentLineIndex = -1;
   this.vt100('> ');
   this.gotoState(3 /* STATE_READLINE */);
+  return false;
 };
 
 Demo.prototype.doReadLine = function() {
@@ -192,6 +207,7 @@ Demo.prototype.doReadLine = function() {
     } else if (ch == '\r' || ch == '\n') {
       this.vt100('\r\n');
       this.gotoState(4 /* STATE_COMMAND */);
+      return false;
     } else if (ch == '\u0008' || ch == '\u007F') {
       if (this.line.length > 0) {
         this.line = this.line.substr(0, this.line.length - 1);
@@ -212,6 +228,7 @@ Demo.prototype.doReadLine = function() {
       break;
     }
   }
+  return true;
 };
 
 Demo.prototype.doCommand = function() {
@@ -244,8 +261,9 @@ Demo.prototype.doCommand = function() {
       this.tokens           = tokens;
       this.gotoState(5 /* STATE_EVAL */);
     }
-    tokens.reset();
   }
+  tokens.reset();
+  return false;
 };
 
 Demo.prototype.doEval = function() {
@@ -253,11 +271,10 @@ Demo.prototype.doEval = function() {
   var cmd                   = this.tokens.nextToken().toUpperCase();
   if (cmd == "HELP") {
     this.vt100('Supported commands:\r\n' +
-               '  HELP LIST RUN\r\n');
+               '  HELP LIST NEW RUN\r\n');
   } else if (cmd == "LIST") {
     if (this.tokens.nextToken() != undefined) {
       this.error();
-      return false;
     } else {
       for (var i = 0; i < this.program.length; i++) {
         var line            = this.program[i];
@@ -270,39 +287,65 @@ Demo.prototype.doEval = function() {
         this.vt100('\r\n');
       }
     }
+  } else if (cmd == "NEW") {
+    if (this.currentLineIndex >= 0) {
+      this.error('Cannot call NEW from a program');
+    } else if (this.program.length == 0) {
+      this.ok();
+    } else {
+      this.vt100('Do you really want to delete the program (y/N) ');
+      this.gotoState(7 /* STATE_NEW_Y_N */);
+    }
   } else if (cmd == "RUN") {
     if (this.tokens.nextToken() != undefined) {
       this.error();
+    } else if (this.program.length > 0) {
+      this.currentLineIndex = 0;
+      this.gotoState(6 /* STATE_EXEC */);
     } else {
-      this.gotoState(6 /* STATE_RUN */);
+      this.ok();
     }
-    return false;
   } else {
     this.error();
+  }
   return false;
-  }
-  return true;
-};
-
-Demo.prototype.doRun = function() {
-  if (this.program.length > 0) {
-    this.currentLineIndex = 0;
-    this.gotoState(7 /* STATE_EXEC */);
-  }
 };
 
 Demo.prototype.doExec = function() {
   this.tokens = this.program[this.currentLineIndex++].tokens();
   this.tokens.reset();
-  if (this.doEval()) {
+  this.doEval();
-    if (this.currentLineIndex >= this.program.length) {
+  if (this.currentLineIndex < 0) {
-      this.gotoState(2 /* STATE_PROMPT */);
+    return false;
+  } else if (this.currentLineIndex >= this.program.length) {
+    this.ok();
     return false;
   } else {
-      this.gotoState(7 /* STATE_EXEC */, 20);
+    this.gotoState(6 /* STATE_EXEC */, 20);
     return true;
   }
+};
+
+Demo.prototype.doNewYN = function() {
+  for (var i = 0; i < this.keys.length; ) {
+    var ch = this.keys.charAt(i++);
+    if (ch == 'n' || ch == 'N' || ch == '\r' || ch == '\n') {
+      this.vt100('N\r\n');
+      this.keys = this.keys.substr(i);
+      this.error('Aborted');
+      return false;
+    } else if (ch == 'y' || ch == 'Y') {
+      this.vt100('Y\r\n');
+      this.program.splice(0, this.program.length);
+      this.keys = this.keys.substr(i);
+      this.ok();
+      return false;
+    } else {
+      this.vt100('\u0007');
     }
+  }
+  this.gotoState(7 /* STATE_NEW_Y_N */);
+  return true;
 };
 
 Demo.prototype.findLine = function(lineNumber) {

demo/demo.jspp

@@ -69,8 +69,8 @@
 #define STATE_READLINE 3
 #define STATE_COMMAND  4
 #define STATE_EVAL     5
-#define STATE_RUN      6
+#define STATE_EXEC     6
-#define STATE_EXEC     7
+#define STATE_NEW_Y_N  7
 
 function extend(subClass, baseClass) {
   function inheritance() { }
@@ -87,6 +87,16 @@ function Demo(container) {
 extend(Demo, VT100);
 
 Demo.prototype.keysPressed = function(ch) {
+  if (this.state == STATE_EXEC) {
+    for (var i = 0; i < ch.length; i++) {
+      var c       = ch.charAt(i);
+      if (c == '\u0003') {
+        this.keys = '';
+        this.error('Interrupted');
+        return;
+      }
+    }
+  }
   this.keys      += ch;
   this.gotoState(this.state);
 };
@@ -97,7 +107,7 @@ Demo.prototype.gotoState = function(state, tmo) {
     if (!tmo) {
       tmo          = 1;
     }
-    this.timer = setTimeout(function(demo) {
+    this.nextTimer = setTimeout(function(demo) {
                                   return function() {
                                     demo.demo();
                                   };
@@ -107,35 +117,31 @@ Demo.prototype.gotoState = function(state, tmo) {
 
 Demo.prototype.demo = function() {
   var done                  = false;
+  this.nextTimer            = undefined;
   while (!done) {
     var state               = this.state;
     this.state              = STATE_IDLE;
     switch (state) {
     case STATE_INIT:
-      this.doInit();
+      done                  = this.doInit();
       break;
     case STATE_PROMPT:
-      this.doPrompt();
+      done                  = this.doPrompt();
       break;
     case STATE_READLINE:
-      this.doReadLine();
+      done                  = this.doReadLine();
-      if (this.state == STATE_READLINE) {
-        done                = true;
-      }
       break;
     case STATE_COMMAND:
-      this.doCommand();
+      done                  = this.doCommand();
       break;
     case STATE_EVAL:
-      this.doEval();
+      done                  = this.doEval();
-      break;
-    case STATE_RUN:
-      this.doRun();
       break;
     case STATE_EXEC:
-      if (this.doExec()) {
+      done                  = this.doExec();
-        return;
+      break;
-      }
+    case STATE_NEW_Y_N:
+      done                  = this.doNewYN();
       break;
     case STATE_IDLE:
     default:
@@ -143,15 +149,22 @@ Demo.prototype.demo = function() {
       break;
     }
   }
-  this.timer   = undefined;
+  this.timer                = this.nextTimer;
+  this.nextTimer            = undefined;
 };
 
+Demo.prototype.ok = function() {
+  this.vt100('OK\r\n');
+  this.gotoState(STATE_PROMPT);
+}
+
 Demo.prototype.error = function(msg) {
   if (msg == undefined) {
     msg                 = 'Syntax Error';
   }
   this.vt100('\u0007? ' + msg + '\r\n');
   this.gotoState(STATE_PROMPT);
+  this.currentLineIndex = -1;
 };
 
 Demo.prototype.doInit = function() {
@@ -170,6 +183,7 @@ Demo.prototype.doInit = function() {
     'Type HELP for a list of commands.\r\n' +
     '\r\n');
   this.gotoState(STATE_PROMPT);
+  return false;
 };
 
 Demo.prototype.doPrompt = function() {
@@ -178,6 +192,7 @@ Demo.prototype.doPrompt = function() {
   this.currentLineIndex = -1;
   this.vt100('> ');
   this.gotoState(STATE_READLINE);
+  return false;
 };
 
 Demo.prototype.doReadLine = function() {
@@ -192,6 +207,7 @@ Demo.prototype.doReadLine = function() {
     } else if (ch == '\r' || ch == '\n') {
       this.vt100('\r\n');
       this.gotoState(STATE_COMMAND);
+      return false;
     } else if (ch == '\u0008' || ch == '\u007F') {
       if (this.line.length > 0) {
         this.line = this.line.substr(0, this.line.length - 1);
@@ -212,6 +228,7 @@ Demo.prototype.doReadLine = function() {
       break;
     }
   }
+  return true;
 };
 
 Demo.prototype.doCommand = function() {
@@ -244,8 +261,9 @@ Demo.prototype.doCommand = function() {
       this.tokens           = tokens;
       this.gotoState(STATE_EVAL);
     }
-    tokens.reset();
   }
+  tokens.reset();
+  return false;
 };
 
 Demo.prototype.doEval = function() {
@@ -253,11 +271,10 @@ Demo.prototype.doEval = function() {
   var cmd                   = this.tokens.nextToken().toUpperCase();
   if (cmd == "HELP") {
     this.vt100('Supported commands:\r\n' +
-               '  HELP LIST RUN\r\n');
+               '  HELP LIST NEW RUN\r\n');
   } else if (cmd == "LIST") {
     if (this.tokens.nextToken() != undefined) {
       this.error();
-      return false;
     } else {
       for (var i = 0; i < this.program.length; i++) {
         var line            = this.program[i];
@@ -270,39 +287,65 @@ Demo.prototype.doEval = function() {
         this.vt100('\r\n');
       }
     }
+  } else if (cmd == "NEW") {
+    if (this.currentLineIndex >= 0) {
+      this.error('Cannot call NEW from a program');
+    } else if (this.program.length == 0) {
+      this.ok();
+    } else {
+      this.vt100('Do you really want to delete the program (y/N) ');
+      this.gotoState(STATE_NEW_Y_N);
+    }
   } else if (cmd == "RUN") {
     if (this.tokens.nextToken() != undefined) {
       this.error();
-    } else {
+    } else if (this.program.length > 0) {
-      this.gotoState(STATE_RUN);
-    }
-    return false;
-  } else {
-    this.error();
-    return false;
-  }
-  return true;
-};
-
-Demo.prototype.doRun = function() {
-  if (this.program.length > 0) {
       this.currentLineIndex = 0;
       this.gotoState(STATE_EXEC);
+    } else {
+      this.ok();
     }
+  } else {
+    this.error();
+  }
+  return false;
 };
 
 Demo.prototype.doExec = function() {
   this.tokens = this.program[this.currentLineIndex++].tokens();
   this.tokens.reset();
-  if (this.doEval()) {
+  this.doEval();
-    if (this.currentLineIndex >= this.program.length) {
+  if (this.currentLineIndex < 0) {
-      this.gotoState(STATE_PROMPT);
+    return false;
+  } else if (this.currentLineIndex >= this.program.length) {
+    this.ok();
     return false;
   } else {
     this.gotoState(STATE_EXEC, 20);
     return true;
   }
+};
+
+Demo.prototype.doNewYN = function() {
+  for (var i = 0; i < this.keys.length; ) {
+    var ch = this.keys.charAt(i++);
+    if (ch == 'n' || ch == 'N' || ch == '\r' || ch == '\n') {
+      this.vt100('N\r\n');
+      this.keys = this.keys.substr(i);
+      this.error('Aborted');
+      return false;
+    } else if (ch == 'y' || ch == 'Y') {
+      this.vt100('Y\r\n');
+      this.program.splice(0, this.program.length);
+      this.keys = this.keys.substr(i);
+      this.ok();
+      return false;
+    } else {
+      this.vt100('\u0007');
     }
+  }
+  this.gotoState(STATE_NEW_Y_N);
+  return true;
 };
 
 Demo.prototype.findLine = function(lineNumber) {