1/* 2 * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/) 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef WTF_RandomNumberSeed_h 27#define WTF_RandomNumberSeed_h 28 29#include "RandomNumber.h" 30#include <stdlib.h> 31#include <time.h> 32 33#if HAVE(SYS_TIME_H) 34#include <sys/time.h> 35#endif 36 37#if OS(UNIX) 38#include <sys/types.h> 39#include <unistd.h> 40#endif 41 42namespace WTF { 43 44inline void initializeRandomNumberGenerator() 45{ 46#if OS(DARWIN) 47 // On Darwin we use arc4random which initialises itself. 48#elif OS(WINCE) 49 // initialize rand() 50 srand(GetTickCount()); 51#elif COMPILER(MSVC) && defined(_CRT_RAND_S) 52 // On Windows we use rand_s which initialises itself 53#elif OS(UNIX) 54 // srandomdev is not guaranteed to exist on linux so we use this poor seed, this should be improved 55 timeval time; 56 gettimeofday(&time, 0); 57 srandom(static_cast<unsigned>(time.tv_usec * getpid())); 58#else 59 srand(static_cast<unsigned>(time(0))); 60#endif 61 62} 63 64} 65 66#endif 67