| /*- |
| * Fowler / Noll / Vo Hash (FNV Hash) |
| * http://www.isthe.com/chongo/tech/comp/fnv/ |
| * |
| * This is an implementation of the algorithms posted above. |
| * This file is placed in the public domain by Peter Wemm. |
| * |
| * $FreeBSD$ |
| */ |
| |
| typedef u_int32_t Fnv32_t; |
| typedef u_int64_t Fnv64_t; |
| |
| #define FNV1_32_INIT ((Fnv32_t) 33554467UL) |
| #define FNV1_64_INIT ((Fnv64_t) 0xcbf29ce484222325ULL) |
| |
| #define FNV_32_PRIME ((Fnv32_t) 0x01000193UL) |
| #define FNV_64_PRIME ((Fnv64_t) 0x100000001b3ULL) |
| |
| static __inline Fnv32_t |
| fnv_32_buf(const void *buf, size_t len, Fnv32_t hval) |
| { |
| const u_int8_t *s = (const u_int8_t *)buf; |
| |
| while (len-- != 0) { |
| hval *= FNV_32_PRIME; |
| hval ^= *s++; |
| } |
| return hval; |
| } |
| |
| static __inline Fnv32_t |
| fnv_32_str(const char *str, Fnv32_t hval) |
| { |
| const u_int8_t *s = (const u_int8_t *)str; |
| Fnv32_t c; |
| |
| while ((c = *s++) != 0) { |
| hval *= FNV_32_PRIME; |
| hval ^= c; |
| } |
| return hval; |
| } |
| |
| static __inline Fnv64_t |
| fnv_64_buf(const void *buf, size_t len, Fnv64_t hval) |
| { |
| const u_int8_t *s = (const u_int8_t *)buf; |
| |
| while (len-- != 0) { |
| hval *= FNV_64_PRIME; |
| hval ^= *s++; |
| } |
| return hval; |
| } |
| |
| static __inline Fnv64_t |
| fnv_64_str(const char *str, Fnv64_t hval) |
| { |
| const u_int8_t *s = (const u_int8_t *)str; |
| u_register_t c; /* 32 bit on i386, 64 bit on alpha,ia64 */ |
| |
| while ((c = *s++) != 0) { |
| hval *= FNV_64_PRIME; |
| hval ^= c; |
| } |
| return hval; |
| } |