gecko-dev/mfbt/HashFunctions.cpp

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
2012-05-21 11:12:37 +00:00
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Implementations of hash functions. */
#include "mozilla/HashFunctions.h"
#include "mozilla/Types.h"
#include <string.h>
namespace mozilla {
uint32_t
HashBytes(const void* aBytes, size_t aLength)
{
uint32_t hash = 0;
const char* b = reinterpret_cast<const char*>(aBytes);
/* Walk word by word. */
size_t i = 0;
for (; i < aLength - (aLength % sizeof(size_t)); i += sizeof(size_t)) {
/* Do an explicitly unaligned load of the data. */
size_t data;
memcpy(&data, b + i, sizeof(size_t));
hash = AddToHash(hash, data, sizeof(data));
}
/* Get the remaining bytes. */
for (; i < aLength; i++) {
hash = AddToHash(hash, b[i]);
}
return hash;
}
} /* namespace mozilla */