1 /* jhash.h: Jenkins hash support.
3 * Copyright (C) 1996 Bob Jenkins (bob_jenkins@burtleburtle.net)
5 * http://burtleburtle.net/bob/hash/
7 * These are the credits from Bob's sources:
9 * lookup2.c, by Bob Jenkins, December 1996, Public Domain.
10 * hash(), hash2(), hash3, and mix() are externally useful functions.
11 * Routines to test the hash are included if SELF_TEST is defined.
12 * You can use this free for any purpose. It has no warranty.
14 * Copyright (C) 2003 David S. Miller (davem@redhat.com)
16 * I've modified Bob's hash to be useful in the Linux kernel, and
17 * any bugs present are surely my fault. -DaveM
20 #ifndef _QUAGGA_JHASH_H
21 #define _QUAGGA_JHASH_H
23 /* The most generic version, hashes an arbitrary sequence
24 * of bytes. No alignment or length assumptions are made about
27 extern u_int32_t jhash(const void *key, u_int32_t length, u_int32_t initval);
29 /* A special optimized version that handles 1 or more of u_int32_ts.
30 * The length parameter here is the number of u_int32_ts in the key.
32 extern u_int32_t jhash2(const u_int32_t *k, u_int32_t length, u_int32_t initval);
34 /* A special ultra-optimized versions that knows they are hashing exactly
37 * NOTE: In partilar the "c += length; __jhash_mix(a,b,c);" normally
38 * done at the end is not done here.
40 extern u_int32_t jhash_3words(u_int32_t a, u_int32_t b, u_int32_t c, u_int32_t initval);
41 extern u_int32_t jhash_2words(u_int32_t a, u_int32_t b, u_int32_t initval);
42 extern u_int32_t jhash_1word(u_int32_t a, u_int32_t initval);
44 #endif /* _QUAGGA_JHASH_H */