/*!
|
|
* ws: a node.js websocket client
|
|
* Copyright(c) 2011 Einar Otto Stangvik <einaros@gmail.com>
|
|
* MIT Licensed
|
|
*/
|
|
|
|
module.exports.BufferUtil = {
|
|
merge: function(mergedBuffer, buffers) {
|
|
var offset = 0;
|
|
for (var i = 0, l = buffers.length; i < l; ++i) {
|
|
var buf = buffers[i];
|
|
buf.copy(mergedBuffer, offset);
|
|
offset += buf.length;
|
|
}
|
|
},
|
|
mask: function(source, mask, output, offset, length) {
|
|
var maskNum = mask.readUInt32LE(0, true);
|
|
var i = 0;
|
|
for (; i < length - 3; i += 4) {
|
|
var num = maskNum ^ source.readUInt32LE(i, true);
|
|
if (num < 0) num = 4294967296 + num;
|
|
output.writeUInt32LE(num, offset + i, true);
|
|
}
|
|
switch (length % 4) {
|
|
case 3: output[offset + i + 2] = source[i + 2] ^ mask[2];
|
|
case 2: output[offset + i + 1] = source[i + 1] ^ mask[1];
|
|
case 1: output[offset + i] = source[i] ^ mask[0];
|
|
case 0:;
|
|
}
|
|
},
|
|
unmask: function(data, mask) {
|
|
var maskNum = mask.readUInt32LE(0, true);
|
|
var length = data.length;
|
|
var i = 0;
|
|
for (; i < length - 3; i += 4) {
|
|
var num = maskNum ^ data.readUInt32LE(i, true);
|
|
if (num < 0) num = 4294967296 + num;
|
|
data.writeUInt32LE(num, i, true);
|
|
}
|
|
switch (length % 4) {
|
|
case 3: data[i + 2] = data[i + 2] ^ mask[2];
|
|
case 2: data[i + 1] = data[i + 1] ^ mask[1];
|
|
case 1: data[i] = data[i] ^ mask[0];
|
|
case 0:;
|
|
}
|
|
}
|
|
}
|