# All files crc.js

100% Statements 26/26
100% Branches 2/2
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100% Lines 22/22

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     "use strict";

    let crcTable = [];

    (function () {
      for (let i = 0; i < 256; i++) {
        let currentCrc = i;
        for (let j = 0; j < 8; j++) {
          if (currentCrc & 1) {
            currentCrc = 0xedb88320 ^ (currentCrc >>> 1);
          } else {
            currentCrc = currentCrc >>> 1;
          }
        }
        crcTable[i] = currentCrc;
      }
    })();

    let CrcCalculator = (module.exports = function () {
      this._crc = -1;
    });

    CrcCalculator.prototype.write = function (data) {
      for (let i = 0; i < data.length; i++) {
        this._crc = crcTable[(this._crc ^ data[i]) & 0xff] ^ (this._crc >>> 8);
      }
      return true;
    };

    CrcCalculator.prototype.crc32 = function () {
      return this._crc ^ -1;
    };

    CrcCalculator.crc32 = function (buf) {
      let crc = -1;
      for (let i = 0; i < buf.length; i++) {
        crc = crcTable[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8);
      }
      return crc ^ -1;
    };