X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fhash.c;h=f7aa9163363a85386fee596d8c5f115006a9df61;hb=410698cf7d0c9364a2ecb61b692e60da737bec78;hp=af8f21bb1bdf22832b2e58c515afffb44704ccbb;hpb=064af42167bf4fc9aaea2702d80ce08074b889c0;p=sliver-openvswitch.git diff --git a/lib/hash.c b/lib/hash.c index af8f21bb1..f7aa91633 100644 --- a/lib/hash.c +++ b/lib/hash.c @@ -1,21 +1,22 @@ /* - * Copyright (c) 2008, 2009 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2012 Nicira, Inc. * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR - * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN - * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF - * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. */ #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; @@ -52,33 +53,51 @@ hash_words(const uint32_t *p, size_t n, uint32_t basis) return c; } +/* Returns the hash of 'a', 'b', and 'c'. */ +uint32_t +hash_3words(uint32_t a, uint32_t b, uint32_t c) +{ + a += 0xdeadbeef; + b += 0xdeadbeef; + c += 0xdeadbeef; + hash_final(&a, &b, &c); + return c; +} + +/* Returns the hash of 'a' and 'b'. */ +uint32_t +hash_2words(uint32_t a, uint32_t b) +{ + return hash_3words(a, b, 0); +} + /* Returns the hash of the 'n' bytes at 'p', starting from 'basis'. */ uint32_t 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;