1 /* 2 * This is the CRC32c polynomial, as outlined by Castagnoli. 3 * x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+x^11+x^10+x^9+ 4 * x^8+x^6+x^0 5 */ 6 #define CRCPOLY_LE 0x82F63B78 7 #define CRCPOLY_BE 0x1EDC6F41 8 9 /* How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64. */ 10 /* For less performance-sensitive, use 4 */ 11 #ifndef CRC_LE_BITS 12 # define CRC_LE_BITS 64 13 #endif 14 #ifndef CRC_BE_BITS 15 # define CRC_BE_BITS 64 16 #endif 17 18 /* 19 * Little-endian CRC computation. Used with serial bit streams sent 20 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC. 21 */ 22 #if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \ 23 CRC_LE_BITS & CRC_LE_BITS-1 24 # error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}" 25 #endif 26 27 /* 28 * Big-endian CRC computation. Used with serial bit streams sent 29 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. 30 */ 31 #if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \ 32 CRC_BE_BITS & CRC_BE_BITS-1 33 # error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}" 34 #endif 35 36 37 #define ___constant_swab32(x) \ 38 ((uint32_t)( \ 39 (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \ 40 (((uint32_t)(x) & (uint32_t)0x0000ff00UL) << 8) | \ 41 (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >> 8) | \ 42 (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24))) 43 44 45 #if (__GNUC__ >= 3) 46 #define likely(x) __builtin_expect(!!(x), 1) 47 #define unlikely(x) __builtin_expect(!!(x), 0) 48 #else 49 #define likely(x) (x) 50 #define unlikely(x) (x) 51 #endif 52