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/*! * 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:; } } }
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