Blame view

static/plugins/novnc/chrome-app/tcp-client.js 9.24 KB
831eac332   zhuzhenchao   add file
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
  /*
  Copyright 2012 Google Inc.
  
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  
       http://www.apache.org/licenses/LICENSE-2.0
  
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  
  Author: Boris Smus (smus@chromium.org)
  */
  
  (function(exports) {
  
    // Define some local variables here.
    var socket = chrome.socket || chrome.experimental.socket;
    var dns = chrome.experimental.dns;
  
    /**
     * Creates an instance of the client
     *
     * @param {String} host The remote host to connect to
     * @param {Number} port The port to connect to at the remote host
     */
    function TcpClient(host, port, pollInterval) {
      this.host = host;
      this.port = port;
      this.pollInterval = pollInterval || 15;
  
      // Callback functions.
      this.callbacks = {
        connect: null,    // Called when socket is connected.
        disconnect: null, // Called when socket is disconnected.
        recvBuffer: null, // Called (as ArrayBuffer) when client receives data from server.
        recvString: null, // Called (as string) when client receives data from server.
        sent: null        // Called when client sends data to server.
      };
  
      // Socket.
      this.socketId = null;
      this.isConnected = false;
  
      log('initialized tcp client');
    }
  
    /**
     * Connects to the TCP socket, and creates an open socket.
     *
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-create
     * @param {Function} callback The function to call on connection
     */
    TcpClient.prototype.connect = function(callback) {
      // First resolve the hostname to an IP.
      dns.resolve(this.host, function(result) {
        this.addr = result.address;
        socket.create('tcp', {}, this._onCreate.bind(this));
  
        // Register connect callback.
        this.callbacks.connect = callback;
      }.bind(this));
    };
  
    /**
     * Sends an arraybuffer/view down the wire to the remote side
     *
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-write
     * @param {String} msg The arraybuffer/view to send
     * @param {Function} callback The function to call when the message has sent
     */
    TcpClient.prototype.sendBuffer = function(buf, callback) {
      if (buf.buffer) {
          buf = buf.buffer;
      }
  
      /*
      // Debug
      var bytes = [], u8 = new Uint8Array(buf);
      for (var i = 0; i < u8.length; i++) {
          bytes.push(u8[i]);
      }
      log("sending bytes: " + (bytes.join(',')));
      */
      
      socket.write(this.socketId, buf, this._onWriteComplete.bind(this));
  
      // Register sent callback.
      this.callbacks.sent = callback;
    };
  
    /**
     * Sends a string down the wire to the remote side
     *
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-write
     * @param {String} msg The string to send
     * @param {Function} callback The function to call when the message has sent
     */
    TcpClient.prototype.sendString = function(msg, callback) {
      /*
      // Debug
      log("sending string: " + msg);
      */
  
      this._stringToArrayBuffer(msg, function(arrayBuffer) {
        socket.write(this.socketId, arrayBuffer, this._onWriteComplete.bind(this));
      }.bind(this));
  
      // Register sent callback.
      this.callbacks.sent = callback;
    };
  
    /**
     * Sets the callback for when a message is received
     *
     * @param {Function} callback The function to call when a message has arrived
     * @param {String} type The callback argument type: "arraybuffer" or "string"
     */
    TcpClient.prototype.addResponseListener = function(callback, type) {
      if (typeof type === "undefined") {
          type = "arraybuffer";
      }
      // Register received callback.
      if (type === "string") {
        this.callbacks.recvString = callback;
      } else {
        this.callbacks.recvBuffer = callback;
      }
    };
  
    /**
     * Sets the callback for when the socket disconnects
     *
     * @param {Function} callback The function to call when the socket disconnects
     * @param {String} type The callback argument type: "arraybuffer" or "string"
     */
    TcpClient.prototype.addDisconnectListener = function(callback) {
      // Register disconnect callback.
      this.callbacks.disconnect = callback;
    };
  
    /**
     * Disconnects from the remote side
     *
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-disconnect
     */
    TcpClient.prototype.disconnect = function() {
      if (this.isConnected) {
        this.isConnected = false;
        socket.disconnect(this.socketId);
        if (this.callbacks.disconnect) {
          this.callbacks.disconnect();
        }
        log('socket disconnected');
      }
    };
  
    /**
     * The callback function used for when we attempt to have Chrome
     * create a socket. If the socket is successfully created
     * we go ahead and connect to the remote side.
     *
     * @private
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-connect
     * @param {Object} createInfo The socket details
     */
    TcpClient.prototype._onCreate = function(createInfo) {
      this.socketId = createInfo.socketId;
      if (this.socketId > 0) {
        socket.connect(this.socketId, this.addr, this.port, this._onConnectComplete.bind(this));
      } else {
        error('Unable to create socket');
      }
    };
  
    /**
     * The callback function used for when we attempt to have Chrome
     * connect to the remote side. If a successful connection is
     * made then polling starts to check for data to read
     *
     * @private
     * @param {Number} resultCode Indicates whether the connection was successful
     */
    TcpClient.prototype._onConnectComplete = function(resultCode) {
      // Start polling for reads.
      this.isConnected = true;
      setTimeout(this._periodicallyRead.bind(this), this.pollInterval);
  
      if (this.callbacks.connect) {
        log('connect complete');
        this.callbacks.connect();
      }
      log('onConnectComplete');
    };
  
    /**
     * Checks for new data to read from the socket
     *
     * @see http://developer.chrome.com/trunk/apps/socket.html#method-read
     */
    TcpClient.prototype._periodicallyRead = function() {
      var that = this;
      socket.getInfo(this.socketId, function (info) {
        if (info.connected) {
          setTimeout(that._periodicallyRead.bind(that), that.pollInterval);
          socket.read(that.socketId, null, that._onDataRead.bind(that));
        } else if (that.isConnected) {
          log('socket disconnect detected');
          that.disconnect();
        }
     });
    };
  
    /**
     * Callback function for when data has been read from the socket.
     * Converts the array buffer that is read in to a string
     * and sends it on for further processing by passing it to
     * the previously assigned callback function.
     *
     * @private
     * @see TcpClient.prototype.addResponseListener
     * @param {Object} readInfo The incoming message
     */
    TcpClient.prototype._onDataRead = function(readInfo) {
      // Call received callback if there's data in the response.
      if (readInfo.resultCode > 0) {
        log('onDataRead');
  
        /*
        // Debug
        var bytes = [], u8 = new Uint8Array(readInfo.data);
        for (var i = 0; i < u8.length; i++) {
            bytes.push(u8[i]);
        }
        log("received bytes: " + (bytes.join(',')));
        */
        
        if (this.callbacks.recvBuffer) {
          // Return raw ArrayBuffer directly.
          this.callbacks.recvBuffer(readInfo.data);
        }
        if (this.callbacks.recvString) {
          // Convert ArrayBuffer to string.
          this._arrayBufferToString(readInfo.data, function(str) {
            this.callbacks.recvString(str);
          }.bind(this));
        }
  
        // Trigger another read right away
        setTimeout(this._periodicallyRead.bind(this), 0);
      }
    };
  
    /**
     * Callback for when data has been successfully
     * written to the socket.
     *
     * @private
     * @param {Object} writeInfo The outgoing message
     */
    TcpClient.prototype._onWriteComplete = function(writeInfo) {
      log('onWriteComplete');
      // Call sent callback.
      if (this.callbacks.sent) {
        this.callbacks.sent(writeInfo);
      }
    };
  
    /**
     * Converts an array buffer to a string
     *
     * @private
     * @param {ArrayBuffer} buf The buffer to convert
     * @param {Function} callback The function to call when conversion is complete
     */
    TcpClient.prototype._arrayBufferToString = function(buf, callback) {
      var bb = new Blob([new Uint8Array(buf)]);
      var f = new FileReader();
      f.onload = function(e) {
        callback(e.target.result);
      };
      f.readAsText(bb);
    };
  
    /**
     * Converts a string to an array buffer
     *
     * @private
     * @param {String} str The string to convert
     * @param {Function} callback The function to call when conversion is complete
     */
    TcpClient.prototype._stringToArrayBuffer = function(str, callback) {
      var bb = new Blob([str]);
      var f = new FileReader();
      f.onload = function(e) {
          callback(e.target.result);
      };
      f.readAsArrayBuffer(bb);
    };
  
    /**
     * Wrapper function for logging
     */
    function log(msg) {
      console.log(msg);
    }
  
    /**
     * Wrapper function for error logging
     */
    function error(msg) {
      console.error(msg);
    }
  
    exports.TcpClient = TcpClient;
  
  })(window);