X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fhash.c;h=41ad1bf2fc96ba8a9d041ef8a1281176cf1e1819;hb=3e34fbdd62bcd79dad4f62ba6ec920d8f3be71bb;hp=61e17b2786416a87535a7739278454d761ba83ba;hpb=1f26e79678c9601477c072021598d4d1f5abfb43;p=openvswitch diff --git a/lib/hash.c b/lib/hash.c index 61e17b27..41ad1bf2 100644 --- a/lib/hash.c +++ b/lib/hash.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2012 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -16,6 +16,7 @@ #include #include "hash.h" #include +#include "unaligned.h" /* Returns the hash of the 'n' 32-bit words at 'p', starting from 'basis'. * 'p' must be properly aligned. */ @@ -30,7 +31,7 @@ hash_words(const uint32_t *p, size_t n, uint32_t basis) a += p[0]; b += p[1]; c += p[2]; - HASH_MIX(a, b, c); + hash_mix(&a, &b, &c); n -= 3; p += 3; } @@ -44,7 +45,7 @@ hash_words(const uint32_t *p, size_t n, uint32_t basis) /* fall through */ case 1: a += p[0]; - HASH_FINAL(a, b, c); + hash_final(&a, &b, &c); /* fall through */ case 0: break; @@ -59,7 +60,7 @@ hash_3words(uint32_t a, uint32_t b, uint32_t c) a += 0xdeadbeef; b += 0xdeadbeef; c += 0xdeadbeef; - HASH_FINAL(a, b, c); + hash_final(&a, &b, &c); return c; } @@ -76,28 +77,43 @@ hash_bytes(const void *p_, size_t n, uint32_t basis) { const uint8_t *p = p_; uint32_t a, b, c; - uint32_t tmp[3]; a = b = c = 0xdeadbeef + n + basis; - while (n >= sizeof tmp) { - memcpy(tmp, p, sizeof tmp); - a += tmp[0]; - b += tmp[1]; - c += tmp[2]; - HASH_MIX(a, b, c); - n -= sizeof tmp; - p += sizeof tmp; + while (n >= 12) { + a += get_unaligned_u32((uint32_t *) p); + b += get_unaligned_u32((uint32_t *) (p + 4)); + c += get_unaligned_u32((uint32_t *) (p + 8)); + hash_mix(&a, &b, &c); + n -= 12; + p += 12; } if (n) { + uint32_t tmp[3]; + tmp[0] = tmp[1] = tmp[2] = 0; memcpy(tmp, p, n); a += tmp[0]; b += tmp[1]; c += tmp[2]; - HASH_FINAL(a, b, c); + hash_final(&a, &b, &c); } return c; } + +/* Returns the hash of the 'n' 32-bit words at 'p', starting from 'basis'. + * 'p' must be properly aligned. */ +uint32_t +mhash_words(const uint32_t p[], size_t n_words, uint32_t basis) +{ + uint32_t hash; + size_t i; + + hash = basis; + for (i = 0; i < n_words; i++) { + hash = mhash_add(hash, p[i]); + } + return mhash_finish(hash, n_words); +}