Add support for charset conversion

README.md

@@ -31,6 +31,9 @@ var io = socketio.listen(httpserver);
 
 // create webtelnet proxy and bind to io
 var webtelnetd = webtelnet(io, conf.telnet.port, conf.telnet.host);
+
+// if you need charset conversion from gbk to utf8
+webtelnetd.setCharset('gbk');
 ```
 
 ## Usage as standalone proxy
@@ -40,11 +43,12 @@ $ [sudo] npm install -g webtelnet
 ```
 
 ```bash
-$ webtelnet <http-port> <telnet-port> [-h <telnet-host>] [-w <path/to/www>]
+$ webtelnet <http-port> <telnet-port> [-h <telnet-host>] [-w <path/to/www>] ［－c <charset>]
 ```
 
 * By default, telnet-host is 127.0.0.1. You can also proxy to other hosts.
 * By default, path/to/www point to WebTelnet web app. You can use customized web app, for example, a web app optimized for specific MUD.
+* By default, charset is utf8. You can try gbk or big5, if you need charset conversion.
 
 Example, if you have a MUD server listening on port 4000, to map to http port 8080:
 

main.js

@@ -34,7 +34,9 @@ if(args._.length < 2) {
     'Syntax: webtelnet <http-port> <telnet-port> [options]\n' +
     'Options: \n' +
     '    [-h <telnet-host>]\n' +
-    '    [-w <path/to/www>]\n' );
+    '    [-w <path/to/www>]\n' +
+    '    [-c <charset>]\n'
+  );
   process.exit(0);
 }
 
@@ -55,3 +57,4 @@ var io = socketio.listen(httpserver);
 
 // create webtelnet proxy and bind to io
 var webtelnetd = webtelnet(io, conf.telnet.port, conf.telnet.host);
+if(args.c) webtelnetd.setCharset(args.c);

package.json

@@ -1,6 +1,6 @@
 {
   "name": "webtelnet",
-  "version": "1.0.1",
+  "version": "1.1.0",
   "description": "WebTelnet is a proxy server to bridge websocket to telnet, enable visiting telnet servers with browsers",
   "main": "./webtelnet-proxy.js",
   "bin": {
@@ -20,17 +20,20 @@
     "mud",
     "webmud"
   ],
-  "author": "Raymond Xie <[email protected]>",
+  "author": {
+    "name": "Raymond Xie",
+    "email": "[email protected]"
+  },
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/mudchina/webtelnet/issues"
   },
   "homepage": "https://github.com/mudchina/webtelnet#README.md",
   "dependencies": {
-    "minimist": "^1.2.0",
     "express": "^4.13.4",
+    "iconv-lite": "^0.4.13",
+    "minimist": "^1.2.0",
     "socket.io": "^1.4.4"
   },
-  "devDependencies": {
-  }
+  "devDependencies": {}
 }

webtelnet-proxy.js

@@ -2,7 +2,36 @@
 
 (function(){
 
-var net = require('net');
+var net = require('net'),
+    iconv = require('iconv-lite');
+
+  // string to uint array
+function unicodeStringToTypedArray(s) {
+    var escstr = encodeURIComponent(s);
+    var binstr = escstr.replace(/%([0-9A-F]{2})/g, function(match, p1) {
+        return String.fromCharCode('0x' + p1);
+    });
+    var ua = new Uint8Array(binstr.length);
+    Array.prototype.forEach.call(binstr, function (ch, i) {
+        ua[i] = ch.charCodeAt(0);
+    });
+    return ua;
+}
+
+// uint array to string
+function typedArrayToUnicodeString(ua) {
+    var binstr = Array.prototype.map.call(ua, function (ch) {
+        return String.fromCharCode(ch);
+    }).join('');
+    var escstr = binstr.replace(/(.)/g, function (m, p) {
+        var code = p.charCodeAt(p).toString(16).toUpperCase();
+        if (code.length < 2) {
+            code = '0' + code;
+        }
+        return '%' + code;
+    });
+    return decodeURIComponent(escstr);
+}
 
 function WebTelnetProxy(io, port, host) {
   if(this && (this instanceof WebTelnetProxy)) {
@@ -27,10 +56,18 @@ WebTelnetProxy.prototype = {
 
     this.port = 23;
     this.host = '127.0.0.1';
+    this.charset = '';
+    return this;
   },
 
   showTraffic: function(y) {
     this.logTraffic = y;
+    return this;
+  },
+
+  setCharset: function(cs) {
+    this.charset = cs;
+    return this;
   },
 
   bind: function(io, port, host) {
@@ -100,6 +137,11 @@ WebTelnetProxy.prototype = {
       //console.log('telnet: ', buf.toString());
       var peerSock = telnet.peerSock;
       if(peerSock) {
+        if(proxy.charset && (proxy.charset !== 'utf8')) {
+          buf = iconv.decode(buf, proxy.charset);
+          console.log(buf);
+          buf = unicodeStringToTypedArray(buf);
+        }
         var arrBuf = new ArrayBuffer(buf.length);
         var view = new Uint8Array(arrBuf);
         for(var i=0; i<buf.length; ++i) {
@@ -128,6 +170,9 @@ WebTelnetProxy.prototype = {
 
     if(proxy.logTraffic) console.log('proxy client connected, socket id: ' + webSock.id);
     webSock.on('stream', function(message) {
+      if(proxy.charset && (proxy.charset !== 'utf8')) {
+        message = iconv.encode(message, proxy.charset);
+      }
       //console.log('websocket: ', message);
       var peerSock = webSock.peerSock;
       if(peerSock) {