/*
* Websock: high-performance binary WebSockets
- * Copyright (C) 2012 Joel Martin
+ * Copyright (C) 2019 The noVNC Authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* Websock is similar to the standard WebSocket object but with extra
import * as Log from './util/logging.js';
-export default function Websock() {
- "use strict";
-
- this._websocket = null; // WebSocket object
-
- this._rQi = 0; // Receive queue index
- this._rQlen = 0; // Next write position in the receive queue
- this._rQbufferSize = 1024 * 1024 * 4; // Receive queue buffer size (4 MiB)
- this._rQmax = this._rQbufferSize / 8;
- // called in init: this._rQ = new Uint8Array(this._rQbufferSize);
- this._rQ = null; // Receive queue
-
- this._sQbufferSize = 1024 * 10; // 10 KiB
- // called in init: this._sQ = new Uint8Array(this._sQbufferSize);
- this._sQlen = 0;
- this._sQ = null; // Send queue
-
- this._eventHandlers = {
- 'message': function () {},
- 'open': function () {},
- 'close': function () {},
- 'error': function () {}
- };
-};
-
// this has performance issues in some versions Chromium, and
// doesn't gain a tremendous amount of performance increase in Firefox
// at the moment. It may be valuable to turn it on in the future.
-var ENABLE_COPYWITHIN = false;
-
-var MAX_RQ_GROW_SIZE = 40 * 1024 * 1024; // 40 MiB
-
-var typedArrayToString = (function () {
- // This is only for PhantomJS, which doesn't like apply-ing
- // with Typed Arrays
- try {
- var arr = new Uint8Array([1, 2, 3]);
- String.fromCharCode.apply(null, arr);
- return function (a) { return String.fromCharCode.apply(null, a); };
- } catch (ex) {
- return function (a) {
- return String.fromCharCode.apply(
- null, Array.prototype.slice.call(a));
+// Also copyWithin() for TypedArrays is not supported in IE 11 or
+// Safari 13 (at the moment we want to support Safari 11).
+const ENABLE_COPYWITHIN = false;
+const MAX_RQ_GROW_SIZE = 40 * 1024 * 1024; // 40 MiB
+
+export default class Websock {
+ constructor() {
+ this._websocket = null; // WebSocket object
+
+ this._rQi = 0; // Receive queue index
+ this._rQlen = 0; // Next write position in the receive queue
+ this._rQbufferSize = 1024 * 1024 * 4; // Receive queue buffer size (4 MiB)
+ // called in init: this._rQ = new Uint8Array(this._rQbufferSize);
+ this._rQ = null; // Receive queue
+
+ this._sQbufferSize = 1024 * 10; // 10 KiB
+ // called in init: this._sQ = new Uint8Array(this._sQbufferSize);
+ this._sQlen = 0;
+ this._sQ = null; // Send queue
+
+ this._eventHandlers = {
+ message: () => {},
+ open: () => {},
+ close: () => {},
+ error: () => {}
};
}
-})();
-Websock.prototype = {
// Getters and Setters
- get_sQ: function () {
+ get sQ() {
return this._sQ;
- },
+ }
- get_rQ: function () {
+ get rQ() {
return this._rQ;
- },
+ }
- get_rQi: function () {
+ get rQi() {
return this._rQi;
- },
+ }
- set_rQi: function (val) {
+ set rQi(val) {
this._rQi = val;
- },
+ }
// Receive Queue
- rQlen: function () {
+ get rQlen() {
return this._rQlen - this._rQi;
- },
+ }
- rQpeek8: function () {
+ rQpeek8() {
return this._rQ[this._rQi];
- },
+ }
+
+ rQskipBytes(bytes) {
+ this._rQi += bytes;
+ }
- rQshift8: function () {
- return this._rQ[this._rQi++];
- },
+ rQshift8() {
+ return this._rQshift(1);
+ }
- rQskip8: function () {
- this._rQi++;
- },
+ rQshift16() {
+ return this._rQshift(2);
+ }
- rQskipBytes: function (num) {
- this._rQi += num;
- },
+ rQshift32() {
+ return this._rQshift(4);
+ }
// TODO(directxman12): test performance with these vs a DataView
- rQshift16: function () {
- return (this._rQ[this._rQi++] << 8) +
- this._rQ[this._rQi++];
- },
-
- rQshift32: function () {
- return (this._rQ[this._rQi++] << 24) +
- (this._rQ[this._rQi++] << 16) +
- (this._rQ[this._rQi++] << 8) +
- this._rQ[this._rQi++];
- },
-
- rQshiftStr: function (len) {
- if (typeof(len) === 'undefined') { len = this.rQlen(); }
- var arr = new Uint8Array(this._rQ.buffer, this._rQi, len);
- this._rQi += len;
- return typedArrayToString(arr);
- },
+ _rQshift(bytes) {
+ let res = 0;
+ for (let byte = bytes - 1; byte >= 0; byte--) {
+ res += this._rQ[this._rQi++] << (byte * 8);
+ }
+ return res;
+ }
+
+ rQshiftStr(len) {
+ if (typeof(len) === 'undefined') { len = this.rQlen; }
+ let str = "";
+ // Handle large arrays in steps to avoid long strings on the stack
+ for (let i = 0; i < len; i += 4096) {
+ let part = this.rQshiftBytes(Math.min(4096, len - i));
+ str += String.fromCharCode.apply(null, part);
+ }
+ return str;
+ }
- rQshiftBytes: function (len) {
- if (typeof(len) === 'undefined') { len = this.rQlen(); }
+ rQshiftBytes(len) {
+ if (typeof(len) === 'undefined') { len = this.rQlen; }
this._rQi += len;
return new Uint8Array(this._rQ.buffer, this._rQi - len, len);
- },
+ }
- rQshiftTo: function (target, len) {
- if (len === undefined) { len = this.rQlen(); }
+ rQshiftTo(target, len) {
+ if (len === undefined) { len = this.rQlen; }
// TODO: make this just use set with views when using a ArrayBuffer to store the rQ
target.set(new Uint8Array(this._rQ.buffer, this._rQi, len));
this._rQi += len;
- },
-
- rQwhole: function () {
- return new Uint8Array(this._rQ.buffer, 0, this._rQlen);
- },
+ }
- rQslice: function (start, end) {
- if (end) {
- return new Uint8Array(this._rQ.buffer, this._rQi + start, end - start);
- } else {
- return new Uint8Array(this._rQ.buffer, this._rQi + start, this._rQlen - this._rQi - start);
- }
- },
+ rQslice(start, end = this.rQlen) {
+ return new Uint8Array(this._rQ.buffer, this._rQi + start, end - start);
+ }
// Check to see if we must wait for 'num' bytes (default to FBU.bytes)
// to be available in the receive queue. Return true if we need to
// wait (and possibly print a debug message), otherwise false.
- rQwait: function (msg, num, goback) {
- var rQlen = this._rQlen - this._rQi; // Skip rQlen() function call
- if (rQlen < num) {
+ rQwait(msg, num, goback) {
+ if (this.rQlen < num) {
if (goback) {
if (this._rQi < goback) {
throw new Error("rQwait cannot backup " + goback + " bytes");
return true; // true means need more data
}
return false;
- },
+ }
// Send Queue
- flush: function () {
+ flush() {
if (this._sQlen > 0 && this._websocket.readyState === WebSocket.OPEN) {
this._websocket.send(this._encode_message());
this._sQlen = 0;
}
- },
+ }
- send: function (arr) {
+ send(arr) {
this._sQ.set(arr, this._sQlen);
this._sQlen += arr.length;
this.flush();
- },
+ }
- send_string: function (str) {
- this.send(str.split('').map(function (chr) {
- return chr.charCodeAt(0);
- }));
- },
+ send_string(str) {
+ this.send(str.split('').map(chr => chr.charCodeAt(0)));
+ }
// Event Handlers
- off: function (evt) {
- this._eventHandlers[evt] = function () {};
- },
+ off(evt) {
+ this._eventHandlers[evt] = () => {};
+ }
- on: function (evt, handler) {
+ on(evt, handler) {
this._eventHandlers[evt] = handler;
- },
+ }
- _allocate_buffers: function () {
+ _allocate_buffers() {
this._rQ = new Uint8Array(this._rQbufferSize);
this._sQ = new Uint8Array(this._sQbufferSize);
- },
+ }
- init: function () {
+ init() {
this._allocate_buffers();
this._rQi = 0;
this._websocket = null;
- },
+ }
- open: function (uri, protocols) {
- var ws_schema = uri.match(/^([a-z]+):\/\//)[1];
+ open(uri, protocols) {
this.init();
this._websocket = new WebSocket(uri, protocols);
this._websocket.binaryType = 'arraybuffer';
this._websocket.onmessage = this._recv_message.bind(this);
- this._websocket.onopen = (function () {
+ this._websocket.onopen = () => {
Log.Debug('>> WebSock.onopen');
if (this._websocket.protocol) {
Log.Info("Server choose sub-protocol: " + this._websocket.protocol);
this._eventHandlers.open();
Log.Debug("<< WebSock.onopen");
- }).bind(this);
- this._websocket.onclose = (function (e) {
+ };
+ this._websocket.onclose = (e) => {
Log.Debug(">> WebSock.onclose");
this._eventHandlers.close(e);
Log.Debug("<< WebSock.onclose");
- }).bind(this);
- this._websocket.onerror = (function (e) {
+ };
+ this._websocket.onerror = (e) => {
Log.Debug(">> WebSock.onerror: " + e);
this._eventHandlers.error(e);
Log.Debug("<< WebSock.onerror: " + e);
- }).bind(this);
- },
+ };
+ }
- close: function () {
+ close() {
if (this._websocket) {
if ((this._websocket.readyState === WebSocket.OPEN) ||
(this._websocket.readyState === WebSocket.CONNECTING)) {
this._websocket.close();
}
- this._websocket.onmessage = function (e) { return; };
+ this._websocket.onmessage = () => {};
}
- },
+ }
// private methods
- _encode_message: function () {
+ _encode_message() {
// Put in a binary arraybuffer
// according to the spec, you can send ArrayBufferViews with the send method
return new Uint8Array(this._sQ.buffer, 0, this._sQlen);
- },
+ }
+
+ // We want to move all the unread data to the start of the queue,
+ // e.g. compacting.
+ // The function also expands the receive que if needed, and for
+ // performance reasons we combine these two actions to avoid
+ // unneccessary copying.
+ _expand_compact_rQ(min_fit) {
+ // if we're using less than 1/8th of the buffer even with the incoming bytes, compact in place
+ // instead of resizing
+ const required_buffer_size = (this._rQlen - this._rQi + min_fit) * 8;
+ const resizeNeeded = this._rQbufferSize < required_buffer_size;
- _expand_compact_rQ: function (min_fit) {
- var resizeNeeded = min_fit || this._rQlen - this._rQi > this._rQbufferSize / 2;
if (resizeNeeded) {
- if (!min_fit) {
- // just double the size if we need to do compaction
- this._rQbufferSize *= 2;
- } else {
- // otherwise, make sure we satisy rQlen - rQi + min_fit < rQbufferSize / 8
- this._rQbufferSize = (this._rQlen - this._rQi + min_fit) * 8;
- }
+ // Make sure we always *at least* double the buffer size, and have at least space for 8x
+ // the current amount of data
+ this._rQbufferSize = Math.max(this._rQbufferSize * 2, required_buffer_size);
}
// we don't want to grow unboundedly
if (this._rQbufferSize > MAX_RQ_GROW_SIZE) {
this._rQbufferSize = MAX_RQ_GROW_SIZE;
- if (this._rQbufferSize - this._rQlen - this._rQi < min_fit) {
+ if (this._rQbufferSize - this.rQlen < min_fit) {
throw new Error("Receive Queue buffer exceeded " + MAX_RQ_GROW_SIZE + " bytes, and the new message could not fit");
}
}
if (resizeNeeded) {
- var old_rQbuffer = this._rQ.buffer;
- this._rQmax = this._rQbufferSize / 8;
+ const old_rQbuffer = this._rQ.buffer;
this._rQ = new Uint8Array(this._rQbufferSize);
- this._rQ.set(new Uint8Array(old_rQbuffer, this._rQi));
+ this._rQ.set(new Uint8Array(old_rQbuffer, this._rQi, this._rQlen - this._rQi));
} else {
if (ENABLE_COPYWITHIN) {
- this._rQ.copyWithin(0, this._rQi);
+ this._rQ.copyWithin(0, this._rQi, this._rQlen);
} else {
- this._rQ.set(new Uint8Array(this._rQ.buffer, this._rQi));
+ this._rQ.set(new Uint8Array(this._rQ.buffer, this._rQi, this._rQlen - this._rQi));
}
}
this._rQlen = this._rQlen - this._rQi;
this._rQi = 0;
- },
+ }
- _decode_message: function (data) {
- // push arraybuffer values onto the end
- var u8 = new Uint8Array(data);
+ // push arraybuffer values onto the end of the receive que
+ _decode_message(data) {
+ const u8 = new Uint8Array(data);
if (u8.length > this._rQbufferSize - this._rQlen) {
this._expand_compact_rQ(u8.length);
}
this._rQ.set(u8, this._rQlen);
this._rQlen += u8.length;
- },
+ }
- _recv_message: function (e) {
+ _recv_message(e) {
this._decode_message(e.data);
- if (this.rQlen() > 0) {
+ if (this.rQlen > 0) {
this._eventHandlers.message();
- // Compact the receive queue
if (this._rQlen == this._rQi) {
+ // All data has now been processed, this means we
+ // can reset the receive queue.
this._rQlen = 0;
this._rQi = 0;
- } else if (this._rQlen > this._rQmax) {
- this._expand_compact_rQ();
}
} else {
Log.Debug("Ignoring empty message");
}
}
-};
+}