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// Note: we can't get significant speed boost here.
// So write code to minimize size - no pregenerated tables
// and array tools dependencies.
// Use ordinary array, since untyped makes no boost here
export default function makeTable() {
var c, table = [];
for (var n = 0; n < 256; n++) {
c = n;
for (var k = 0; k < 8; k++) {
c = ((c & 1) ? (0xEDB88320 ^ (c >>> 1)) : (c >>> 1));
}
table[n] = c;
}
return table;
}
// Create table on load. Just 255 signed longs. Not a problem.
var crcTable = makeTable();
function crc32(crc, buf, len, pos) {
var t = crcTable,
end = pos + len;
crc ^= -1;
for (var i = pos; i < end; i++) {
crc = (crc >>> 8) ^ t[(crc ^ buf[i]) & 0xFF];
}
return (crc ^ (-1)); // >>> 0;
}
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