+/*
+ * This is an implementation of CRC32 & CRC16. The polynomials have been
+ * offline computed for faster generation at the cost of larger code size.
+ *
+ * CRC32 Polynomial: 0xEDB88320
+ * CRC16 Polynomial: 0x00001021
+ */
+static const uint32_t util_crc32_table[] = {
+ 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
+};
+static const uint16_t util_crc16_table[] = {
+ 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5,
+ 0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B,
+ 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210,
+ 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
+ 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C,
+ 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401,
+ 0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B,
+ 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
+ 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6,
+ 0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738,
+ 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5,
+ 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
+ 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969,
+ 0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96,
+ 0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC,
+ 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
+ 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03,
+ 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD,
+ 0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6,
+ 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
+ 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A,
+ 0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB,
+ 0xD10C, 0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1,
+ 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
+ 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C,
+ 0xE37F, 0xF35E, 0x02B1, 0x1290, 0x22F3, 0x32D2,
+ 0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB,
+ 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
+ 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447,
+ 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8,
+ 0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2,
+ 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
+ 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9,
+ 0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827,
+ 0x18C0, 0x08E1, 0x3882, 0x28A3, 0xCB7D, 0xDB5C,
+ 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
+ 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0,
+ 0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D,
+ 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07,
+ 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
+ 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA,
+ 0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74,
+ 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
+};
+
+/*
+ * Implements a CRC function for X worth bits using (uint[X]_t)
+ * as type. and util_crc[X]_table.
+ */
+#define CRC(X) \
+uint##X##_t util_crc##X(const char *k, int len, const short clamp) { \
+ register uint##X##_t h= (uint##X##_t)0xFFFFFFFF; \
+ for (; len; --len, ++k) \
+ h = util_crc##X##_table[(h^((unsigned char)*k))&0xFF]^(h>>8); \
+ return (~h)%clamp; \
+}
+CRC(32)
+CRC(16)
+#undef CRC