NxTIC/public_html/js/lib/crc32.js

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var makeCRCTable = function(){
var c;
var crcTable = [];
for(var n =0; n < 256; n++){
c = n;
for(var k =0; k < 8; k++){
c = ((c&1) ? (0xEDB88320 ^ (c >>> 1)) : (c >>> 1));
}
crcTable[n] = c;
}
return crcTable;
};
var crc32 = function(str) {
var crcTable = window.crcTable || (window.crcTable = makeCRCTable());
var crc = 0 ^ (-1);
for (var i = 0; i < str.length; i++ ) {
crc = (crc >>> 8) ^ crcTable[(crc ^ str.charCodeAt(i)) & 0xFF];
}
return (crc ^ (-1)) >>> 0;
};