mfbt/HashFunctions.cpp
author Mike Hommey <mh+mozilla@glandium.org>
Mon, 11 Jun 2012 08:10:28 +0200
changeset 101188 a78601d88586dfae6ce4a8b1912413cdb3b57c14
parent 100672 1a0f4431003105008d31616e75b8db2d3291d54f
child 102045 617cb36ead5971a182c09298ea2d457aeaf3fd9f
permissions -rw-r--r--
Bug 759115 - Move Android SDK/NDK checks in build/autoconf/android.m4, and bump minimum Android SDK API level we require to 14 for mobile/android. r=ted

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * 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 <string.h>

namespace mozilla {

MFBT_API(uint32_t)
HashBytes(const void* bytes, size_t length)
{
  uint32_t hash = 0;
  const char* b = reinterpret_cast<const char*>(bytes);

  /* Walk word by word. */
  size_t i = 0;
  for (; i < length - (length % 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 < length; i++)
    hash = AddToHash(hash, b[i]);

  return hash;
}

} /* namespace mozilla */