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/*
* Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef WTF_RandomNumberSeed_h
#define WTF_RandomNumberSeed_h
#include <stdlib.h>
#include <time.h>
#if HAVE(SYS_TIME_H)
#include <sys/time.h>
#endif
#if OS(UNIX)
#include <sys/types.h>
#include <unistd.h>
#endif
#if USE(MERSENNE_TWISTER_19937)
extern "C" {
void init_by_array(unsigned long init_key[],int key_length);
}
#endif
// Internal JavaScriptCore usage only
namespace WTF {
inline void initializeRandomNumberGenerator()
{
#if OS(DARWIN)
// On Darwin we use arc4random which initialises itself.
#elif OS(WINCE)
// initialize rand()
srand(GetTickCount());
#elif COMPILER(MSVC) && defined(_CRT_RAND_S)
// On Windows we use rand_s which initialises itself
#elif OS(UNIX) && !defined(__LB_SHELL__)
// srandomdev is not guaranteed to exist on linux so we use this poor seed, this should be improved
timeval time;
gettimeofday(&time, 0);
srandom(static_cast<unsigned>(time.tv_usec * getpid()));
#elif OS(STARBOARD)
// Starboard's random initializes itself.
#else
srand(static_cast<unsigned>(time(0)));
#endif
#if USE(MERSENNE_TWISTER_19937)
// use rand() to initialize the Mersenne Twister random number generator.
unsigned long initializationBuffer[4];
initializationBuffer[0] = (rand() << 16) | rand();
initializationBuffer[1] = (rand() << 16) | rand();
initializationBuffer[2] = (rand() << 16) | rand();
initializationBuffer[3] = (rand() << 16) | rand();
init_by_array(initializationBuffer, 4);
#endif
}
}
#endif