systemvm/agent/noVNC/core/websock.js - cloudstack - Git at Google

 /*
  * Websock: high-performance binary WebSockets
  * Copyright (C) 2018 The noVNC Authors
  * Licensed under MPL 2.0 (see LICENSE.txt)
  *
  * Websock is similar to the standard WebSocket object but with extra
  * buffer handling.
  *
  * Websock has built-in receive queue buffering; the message event
  * does not contain actual data but is simply a notification that
  * there is new data available. Several rQ* methods are available to
  * read binary data off of the receive queue.
  */

 import * as Log from './util/logging.js';

 // 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.
 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)
         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: () => {},
             open: () => {},
             close: () => {},
             error: () => {}
         };
     }

     // Getters and Setters
     get sQ() {
         return this._sQ;
     }

     get rQ() {
         return this._rQ;
     }

     get rQi() {
         return this._rQi;
     }

     set rQi(val) {
         this._rQi = val;
     }

     // Receive Queue
     get rQlen() {
         return this._rQlen - this._rQi;
     }

     rQpeek8() {
         return this._rQ[this._rQi];
     }

     rQskipBytes(bytes) {
         this._rQi += bytes;
     }

     rQshift8() {
         return this._rQshift(1);
     }

     rQshift16() {
         return this._rQshift(2);
     }

     rQshift32() {
         return this._rQshift(4);
     }

     // TODO(directxman12): test performance with these vs a DataView
     _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(len) {
         if (typeof(len) === 'undefined') { len = this.rQlen; }
         this._rQi += len;
         return new Uint8Array(this._rQ.buffer, this._rQi - len, len);
     }

     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;
     }

     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(msg, num, goback) {
         if (this.rQlen < num) {
             if (goback) {
                 if (this._rQi < goback) {
                     throw new Error("rQwait cannot backup " + goback + " bytes");
                 }
                 this._rQi -= goback;
             }
             return true; // true means need more data
         }
         return false;
     }

     // Send Queue

     flush() {
         if (this._sQlen > 0 && this._websocket.readyState === WebSocket.OPEN) {
             this._websocket.send(this._encode_message());
             this._sQlen = 0;
         }
     }

     send(arr) {
         this._sQ.set(arr, this._sQlen);
         this._sQlen += arr.length;
         this.flush();
     }

     send_string(str) {
         this.send(str.split('').map(chr => chr.charCodeAt(0)));
     }

     // Event Handlers
     off(evt) {
         this._eventHandlers[evt] = () => {};
     }

     on(evt, handler) {
         this._eventHandlers[evt] = handler;
     }

     _allocate_buffers() {
         this._rQ = new Uint8Array(this._rQbufferSize);
         this._sQ = new Uint8Array(this._sQbufferSize);
     }

     init() {
         this._allocate_buffers();
         this._rQi = 0;
         this._websocket = null;
     }

     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 = () => {
             Log.Debug('>> WebSock.onopen');
             if (this._websocket.protocol) {
                 Log.Info("Server choose sub-protocol: " + this._websocket.protocol);
             }

             this._eventHandlers.open();
             Log.Debug("<< WebSock.onopen");
         };
         this._websocket.onclose = (e) => {
             Log.Debug(">> WebSock.onclose");
             this._eventHandlers.close(e);
             Log.Debug("<< WebSock.onclose");
         };
         this._websocket.onerror = (e) => {
             Log.Debug(">> WebSock.onerror: " + e);
             this._eventHandlers.error(e);
             Log.Debug("<< WebSock.onerror: " + e);
         };
     }

     close() {
         if (this._websocket) {
             if ((this._websocket.readyState === WebSocket.OPEN) ||
                     (this._websocket.readyState === WebSocket.CONNECTING)) {
                 Log.Info("Closing WebSocket connection");
                 this._websocket.close();
             }

             this._websocket.onmessage = () => {};
         }
     }

     // private methods
     _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);
     }

     _expand_compact_rQ(min_fit) {
         const resizeNeeded = min_fit || this.rQlen > 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 + min_fit) * 8;
             }
         }

         // 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 < min_fit) {
                 throw new Error("Receive Queue buffer exceeded " + MAX_RQ_GROW_SIZE + " bytes, and the new message could not fit");
             }
         }

         if (resizeNeeded) {
             const old_rQbuffer = this._rQ.buffer;
             this._rQmax = this._rQbufferSize / 8;
             this._rQ = new Uint8Array(this._rQbufferSize);
             this._rQ.set(new Uint8Array(old_rQbuffer, this._rQi));
         } else {
             if (ENABLE_COPYWITHIN) {
                 this._rQ.copyWithin(0, this._rQi);
             } else {
                 this._rQ.set(new Uint8Array(this._rQ.buffer, this._rQi));
             }
         }

         this._rQlen = this._rQlen - this._rQi;
         this._rQi = 0;
     }

     _decode_message(data) {
         // push arraybuffer values onto the end
         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(e) {
         this._decode_message(e.data);
         if (this.rQlen > 0) {
             this._eventHandlers.message();
             // Compact the receive queue
             if (this._rQlen == this._rQi) {
                 this._rQlen = 0;
                 this._rQi = 0;
             } else if (this._rQlen > this._rQmax) {
                 this._expand_compact_rQ();
             }
         } else {
             Log.Debug("Ignoring empty message");
         }
     }
 }
	/*
	* Websock: high-performance binary WebSockets
	* Copyright (C) 2018 The noVNC Authors
	* Licensed under MPL 2.0 (see LICENSE.txt)
	*
	* Websock is similar to the standard WebSocket object but with extra
	* buffer handling.
	*
	* Websock has built-in receive queue buffering; the message event
	* does not contain actual data but is simply a notification that
	* there is new data available. Several rQ* methods are available to
	* read binary data off of the receive queue.
	*/

	import * as Log from './util/logging.js';

	// 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.
	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)
	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: () => {},
	open: () => {},
	close: () => {},
	error: () => {}
	};
	}

	// Getters and Setters
	get sQ() {
	return this._sQ;
	}

	get rQ() {
	return this._rQ;
	}

	get rQi() {
	return this._rQi;
	}

	set rQi(val) {
	this._rQi = val;
	}

	// Receive Queue
	get rQlen() {
	return this._rQlen - this._rQi;
	}

	rQpeek8() {
	return this._rQ[this._rQi];
	}

	rQskipBytes(bytes) {
	this._rQi += bytes;
	}

	rQshift8() {
	return this._rQshift(1);
	}

	rQshift16() {
	return this._rQshift(2);
	}

	rQshift32() {
	return this._rQshift(4);
	}

	// TODO(directxman12): test performance with these vs a DataView
	_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(len) {
	if (typeof(len) === 'undefined') { len = this.rQlen; }
	this._rQi += len;
	return new Uint8Array(this._rQ.buffer, this._rQi - len, len);
	}

	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;
	}

	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(msg, num, goback) {
	if (this.rQlen < num) {
	if (goback) {
	if (this._rQi < goback) {
	throw new Error("rQwait cannot backup " + goback + " bytes");
	}
	this._rQi -= goback;
	}
	return true; // true means need more data
	}
	return false;
	}

	// Send Queue

	flush() {
	if (this._sQlen > 0 && this._websocket.readyState === WebSocket.OPEN) {
	this._websocket.send(this._encode_message());
	this._sQlen = 0;
	}
	}

	send(arr) {
	this._sQ.set(arr, this._sQlen);
	this._sQlen += arr.length;
	this.flush();
	}

	send_string(str) {
	this.send(str.split('').map(chr => chr.charCodeAt(0)));
	}

	// Event Handlers
	off(evt) {
	this._eventHandlers[evt] = () => {};
	}

	on(evt, handler) {
	this._eventHandlers[evt] = handler;
	}

	_allocate_buffers() {
	this._rQ = new Uint8Array(this._rQbufferSize);
	this._sQ = new Uint8Array(this._sQbufferSize);
	}

	init() {
	this._allocate_buffers();
	this._rQi = 0;
	this._websocket = null;
	}

	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 = () => {
	Log.Debug('>> WebSock.onopen');
	if (this._websocket.protocol) {
	Log.Info("Server choose sub-protocol: " + this._websocket.protocol);
	}

	this._eventHandlers.open();
	Log.Debug("<< WebSock.onopen");
	};
	this._websocket.onclose = (e) => {
	Log.Debug(">> WebSock.onclose");
	this._eventHandlers.close(e);
	Log.Debug("<< WebSock.onclose");
	};
	this._websocket.onerror = (e) => {
	Log.Debug(">> WebSock.onerror: " + e);
	this._eventHandlers.error(e);
	Log.Debug("<< WebSock.onerror: " + e);
	};
	}

	close() {
	if (this._websocket) {
	if ((this._websocket.readyState === WebSocket.OPEN) \|\|
	(this._websocket.readyState === WebSocket.CONNECTING)) {
	Log.Info("Closing WebSocket connection");
	this._websocket.close();
	}

	this._websocket.onmessage = () => {};
	}
	}

	// private methods
	_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);
	}

	_expand_compact_rQ(min_fit) {
	const resizeNeeded = min_fit \|\| this.rQlen > 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 + min_fit) * 8;
	}
	}

	// 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 < min_fit) {
	throw new Error("Receive Queue buffer exceeded " + MAX_RQ_GROW_SIZE + " bytes, and the new message could not fit");
	}
	}

	if (resizeNeeded) {
	const old_rQbuffer = this._rQ.buffer;
	this._rQmax = this._rQbufferSize / 8;
	this._rQ = new Uint8Array(this._rQbufferSize);
	this._rQ.set(new Uint8Array(old_rQbuffer, this._rQi));
	} else {
	if (ENABLE_COPYWITHIN) {
	this._rQ.copyWithin(0, this._rQi);
	} else {
	this._rQ.set(new Uint8Array(this._rQ.buffer, this._rQi));
	}
	}

	this._rQlen = this._rQlen - this._rQi;
	this._rQi = 0;
	}

	_decode_message(data) {
	// push arraybuffer values onto the end
	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(e) {
	this._decode_message(e.data);
	if (this.rQlen > 0) {
	this._eventHandlers.message();
	// Compact the receive queue
	if (this._rQlen == this._rQi) {
	this._rQlen = 0;
	this._rQi = 0;
	} else if (this._rQlen > this._rQmax) {
	this._expand_compact_rQ();
	}
	} else {
	Log.Debug("Ignoring empty message");
	}
	}
	}