1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/mfbt/HashFunctions.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,38 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/* Implementations of hash functions. */
1.10 +
1.11 +#include "mozilla/HashFunctions.h"
1.12 +#include "mozilla/Types.h"
1.13 +
1.14 +#include <string.h>
1.15 +
1.16 +namespace mozilla {
1.17 +
1.18 +uint32_t
1.19 +HashBytes(const void* bytes, size_t length)
1.20 +{
1.21 + uint32_t hash = 0;
1.22 + const char* b = reinterpret_cast<const char*>(bytes);
1.23 +
1.24 + /* Walk word by word. */
1.25 + size_t i = 0;
1.26 + for (; i < length - (length % sizeof(size_t)); i += sizeof(size_t)) {
1.27 + /* Do an explicitly unaligned load of the data. */
1.28 + size_t data;
1.29 + memcpy(&data, b + i, sizeof(size_t));
1.30 +
1.31 + hash = AddToHash(hash, data, sizeof(data));
1.32 + }
1.33 +
1.34 + /* Get the remaining bytes. */
1.35 + for (; i < length; i++)
1.36 + hash = AddToHash(hash, b[i]);
1.37 +
1.38 + return hash;
1.39 +}
1.40 +
1.41 +} /* namespace mozilla */
