| // Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file | 
 | // for details. All rights reserved. Use of this source code is governed by a | 
 | // BSD-style license that can be found in the LICENSE file. | 
 |  | 
 | const List<int> _crc32Table = [ | 
 |   0x00000000, | 
 |   0x77073096, | 
 |   0xEE0E612C, | 
 |   0x990951BA, | 
 |   0x076DC419, | 
 |   0x706AF48F, | 
 |   0xE963A535, | 
 |   0x9E6495A3, | 
 |   0x0EDB8832, | 
 |   0x79DCB8A4, | 
 |   0xE0D5E91E, | 
 |   0x97D2D988, | 
 |   0x09B64C2B, | 
 |   0x7EB17CBD, | 
 |   0xE7B82D07, | 
 |   0x90BF1D91, | 
 |   0x1DB71064, | 
 |   0x6AB020F2, | 
 |   0xF3B97148, | 
 |   0x84BE41DE, | 
 |   0x1ADAD47D, | 
 |   0x6DDDE4EB, | 
 |   0xF4D4B551, | 
 |   0x83D385C7, | 
 |   0x136C9856, | 
 |   0x646BA8C0, | 
 |   0xFD62F97A, | 
 |   0x8A65C9EC, | 
 |   0x14015C4F, | 
 |   0x63066CD9, | 
 |   0xFA0F3D63, | 
 |   0x8D080DF5, | 
 |   0x3B6E20C8, | 
 |   0x4C69105E, | 
 |   0xD56041E4, | 
 |   0xA2677172, | 
 |   0x3C03E4D1, | 
 |   0x4B04D447, | 
 |   0xD20D85FD, | 
 |   0xA50AB56B, | 
 |   0x35B5A8FA, | 
 |   0x42B2986C, | 
 |   0xDBBBC9D6, | 
 |   0xACBCF940, | 
 |   0x32D86CE3, | 
 |   0x45DF5C75, | 
 |   0xDCD60DCF, | 
 |   0xABD13D59, | 
 |   0x26D930AC, | 
 |   0x51DE003A, | 
 |   0xC8D75180, | 
 |   0xBFD06116, | 
 |   0x21B4F4B5, | 
 |   0x56B3C423, | 
 |   0xCFBA9599, | 
 |   0xB8BDA50F, | 
 |   0x2802B89E, | 
 |   0x5F058808, | 
 |   0xC60CD9B2, | 
 |   0xB10BE924, | 
 |   0x2F6F7C87, | 
 |   0x58684C11, | 
 |   0xC1611DAB, | 
 |   0xB6662D3D, | 
 |   0x76DC4190, | 
 |   0x01DB7106, | 
 |   0x98D220BC, | 
 |   0xEFD5102A, | 
 |   0x71B18589, | 
 |   0x06B6B51F, | 
 |   0x9FBFE4A5, | 
 |   0xE8B8D433, | 
 |   0x7807C9A2, | 
 |   0x0F00F934, | 
 |   0x9609A88E, | 
 |   0xE10E9818, | 
 |   0x7F6A0DBB, | 
 |   0x086D3D2D, | 
 |   0x91646C97, | 
 |   0xE6635C01, | 
 |   0x6B6B51F4, | 
 |   0x1C6C6162, | 
 |   0x856530D8, | 
 |   0xF262004E, | 
 |   0x6C0695ED, | 
 |   0x1B01A57B, | 
 |   0x8208F4C1, | 
 |   0xF50FC457, | 
 |   0x65B0D9C6, | 
 |   0x12B7E950, | 
 |   0x8BBEB8EA, | 
 |   0xFCB9887C, | 
 |   0x62DD1DDF, | 
 |   0x15DA2D49, | 
 |   0x8CD37CF3, | 
 |   0xFBD44C65, | 
 |   0x4DB26158, | 
 |   0x3AB551CE, | 
 |   0xA3BC0074, | 
 |   0xD4BB30E2, | 
 |   0x4ADFA541, | 
 |   0x3DD895D7, | 
 |   0xA4D1C46D, | 
 |   0xD3D6F4FB, | 
 |   0x4369E96A, | 
 |   0x346ED9FC, | 
 |   0xAD678846, | 
 |   0xDA60B8D0, | 
 |   0x44042D73, | 
 |   0x33031DE5, | 
 |   0xAA0A4C5F, | 
 |   0xDD0D7CC9, | 
 |   0x5005713C, | 
 |   0x270241AA, | 
 |   0xBE0B1010, | 
 |   0xC90C2086, | 
 |   0x5768B525, | 
 |   0x206F85B3, | 
 |   0xB966D409, | 
 |   0xCE61E49F, | 
 |   0x5EDEF90E, | 
 |   0x29D9C998, | 
 |   0xB0D09822, | 
 |   0xC7D7A8B4, | 
 |   0x59B33D17, | 
 |   0x2EB40D81, | 
 |   0xB7BD5C3B, | 
 |   0xC0BA6CAD, | 
 |   0xEDB88320, | 
 |   0x9ABFB3B6, | 
 |   0x03B6E20C, | 
 |   0x74B1D29A, | 
 |   0xEAD54739, | 
 |   0x9DD277AF, | 
 |   0x04DB2615, | 
 |   0x73DC1683, | 
 |   0xE3630B12, | 
 |   0x94643B84, | 
 |   0x0D6D6A3E, | 
 |   0x7A6A5AA8, | 
 |   0xE40ECF0B, | 
 |   0x9309FF9D, | 
 |   0x0A00AE27, | 
 |   0x7D079EB1, | 
 |   0xF00F9344, | 
 |   0x8708A3D2, | 
 |   0x1E01F268, | 
 |   0x6906C2FE, | 
 |   0xF762575D, | 
 |   0x806567CB, | 
 |   0x196C3671, | 
 |   0x6E6B06E7, | 
 |   0xFED41B76, | 
 |   0x89D32BE0, | 
 |   0x10DA7A5A, | 
 |   0x67DD4ACC, | 
 |   0xF9B9DF6F, | 
 |   0x8EBEEFF9, | 
 |   0x17B7BE43, | 
 |   0x60B08ED5, | 
 |   0xD6D6A3E8, | 
 |   0xA1D1937E, | 
 |   0x38D8C2C4, | 
 |   0x4FDFF252, | 
 |   0xD1BB67F1, | 
 |   0xA6BC5767, | 
 |   0x3FB506DD, | 
 |   0x48B2364B, | 
 |   0xD80D2BDA, | 
 |   0xAF0A1B4C, | 
 |   0x36034AF6, | 
 |   0x41047A60, | 
 |   0xDF60EFC3, | 
 |   0xA867DF55, | 
 |   0x316E8EEF, | 
 |   0x4669BE79, | 
 |   0xCB61B38C, | 
 |   0xBC66831A, | 
 |   0x256FD2A0, | 
 |   0x5268E236, | 
 |   0xCC0C7795, | 
 |   0xBB0B4703, | 
 |   0x220216B9, | 
 |   0x5505262F, | 
 |   0xC5BA3BBE, | 
 |   0xB2BD0B28, | 
 |   0x2BB45A92, | 
 |   0x5CB36A04, | 
 |   0xC2D7FFA7, | 
 |   0xB5D0CF31, | 
 |   0x2CD99E8B, | 
 |   0x5BDEAE1D, | 
 |   0x9B64C2B0, | 
 |   0xEC63F226, | 
 |   0x756AA39C, | 
 |   0x026D930A, | 
 |   0x9C0906A9, | 
 |   0xEB0E363F, | 
 |   0x72076785, | 
 |   0x05005713, | 
 |   0x95BF4A82, | 
 |   0xE2B87A14, | 
 |   0x7BB12BAE, | 
 |   0x0CB61B38, | 
 |   0x92D28E9B, | 
 |   0xE5D5BE0D, | 
 |   0x7CDCEFB7, | 
 |   0x0BDBDF21, | 
 |   0x86D3D2D4, | 
 |   0xF1D4E242, | 
 |   0x68DDB3F8, | 
 |   0x1FDA836E, | 
 |   0x81BE16CD, | 
 |   0xF6B9265B, | 
 |   0x6FB077E1, | 
 |   0x18B74777, | 
 |   0x88085AE6, | 
 |   0xFF0F6A70, | 
 |   0x66063BCA, | 
 |   0x11010B5C, | 
 |   0x8F659EFF, | 
 |   0xF862AE69, | 
 |   0x616BFFD3, | 
 |   0x166CCF45, | 
 |   0xA00AE278, | 
 |   0xD70DD2EE, | 
 |   0x4E048354, | 
 |   0x3903B3C2, | 
 |   0xA7672661, | 
 |   0xD06016F7, | 
 |   0x4969474D, | 
 |   0x3E6E77DB, | 
 |   0xAED16A4A, | 
 |   0xD9D65ADC, | 
 |   0x40DF0B66, | 
 |   0x37D83BF0, | 
 |   0xA9BCAE53, | 
 |   0xDEBB9EC5, | 
 |   0x47B2CF7F, | 
 |   0x30B5FFE9, | 
 |   0xBDBDF21C, | 
 |   0xCABAC28A, | 
 |   0x53B39330, | 
 |   0x24B4A3A6, | 
 |   0xBAD03605, | 
 |   0xCDD70693, | 
 |   0x54DE5729, | 
 |   0x23D967BF, | 
 |   0xB3667A2E, | 
 |   0xC4614AB8, | 
 |   0x5D681B02, | 
 |   0x2A6F2B94, | 
 |   0xB40BBE37, | 
 |   0xC30C8EA1, | 
 |   0x5A05DF1B, | 
 |   0x2D02EF8D | 
 | ]; | 
 |  | 
 | /// Get the CRC-32 checksum of the given array. You can append bytes to an | 
 | /// already computed crc by specifying the previous [crc] value. | 
 | int getCrc32(List<int> array, [int crc = 0]) { | 
 |   int len = array.length; | 
 |   crc = crc ^ 0xffffffff; | 
 |   int ip = 0; | 
 |   while (len >= 8) { | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     len -= 8; | 
 |   } | 
 |   if (len > 0) { | 
 |     do { | 
 |       crc = _crc32Table[(crc ^ array[ip++]) & 0xff] ^ (crc >> 8); | 
 |     } while (--len > 0); | 
 |   } | 
 |   return crc ^ 0xffffffff; | 
 | } |