e5aa87aeeb
Seeing as since:
commit e9531b792d
Date: Tue Feb 6 14:39:47 2024 +0100
sal: rtlRandomPool: require OS random device, abort if not present
Both rtl_random_createPool() and rtl_random_getBytes() first try to get
random data from the OS, via /dev/urandom or rand_s() (documented to
call RtlGenRandom(), see [1]).
we don't use the initial arg to rtl_random_getBytes anymore, drop the
requirement to have one. Then simplify our usages of that, and
addtionally deprecate rtl_random_createPool and rtl_random_destroyPool.
Change-Id: I13dcc067714a8a741a4e8f2bfcf2006373f832c4
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/167067
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolan.mcnamara@collabora.com>
124 lines
3.7 KiB
C++
124 lines
3.7 KiB
C++
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
|
|
/*
|
|
* This file is part of the LibreOffice project.
|
|
*
|
|
* 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/.
|
|
*
|
|
* Contributor(s):
|
|
* Copyright (C) 2012 Tino Kluge <tino.kluge@hrz.tu-chemnitz.de>
|
|
*/
|
|
|
|
#include <comphelper/random.hxx>
|
|
#include <sal/log.hxx>
|
|
#include <assert.h>
|
|
#include <time.h>
|
|
#include <mutex>
|
|
#include <random>
|
|
#include <rtl/random.h>
|
|
#include <stdexcept>
|
|
#if defined HAVE_VALGRIND_HEADERS
|
|
#include <valgrind/memcheck.h>
|
|
#endif
|
|
|
|
// this is nothing but a simple wrapper around
|
|
// the std::random generators
|
|
|
|
namespace comphelper::rng
|
|
{
|
|
// underlying random number generator
|
|
// std::mt19937 implements the Mersenne twister algorithm which
|
|
// is fast and has good statistical properties, it produces integers
|
|
// in the range of [0, 2^32-1] internally
|
|
// memory requirement: 625*sizeof(uint32_t)
|
|
// http://en.wikipedia.org/wiki/Mersenne_twister
|
|
#define STD_RNG_ALGO std::mt19937
|
|
|
|
namespace
|
|
{
|
|
struct RandomNumberGenerator
|
|
{
|
|
std::mutex mutex;
|
|
STD_RNG_ALGO global_rng;
|
|
RandomNumberGenerator() { reseed(); }
|
|
|
|
void reseed()
|
|
{
|
|
// make RR easier to use, breaks easily without the RNG being repeatable
|
|
bool bRepeatable = (getenv("SAL_RAND_REPEATABLE") != nullptr) || (getenv("RR") != nullptr);
|
|
// valgrind on some platforms (e.g.Ubuntu16.04) does not support the new Intel RDRAND instructions,
|
|
// which leads to "Illegal Opcode" errors, so just turn off randomness.
|
|
#if defined HAVE_VALGRIND_HEADERS
|
|
if (RUNNING_ON_VALGRIND)
|
|
bRepeatable = true;
|
|
#endif
|
|
if (bRepeatable)
|
|
{
|
|
global_rng.seed(42);
|
|
return;
|
|
}
|
|
|
|
size_t seed = 0;
|
|
if (rtl_random_getBytes(nullptr, &seed, sizeof(seed)) != rtl_Random_E_None)
|
|
seed = 0;
|
|
|
|
// initialises the state of the global random number generator
|
|
// should only be called once.
|
|
// (note, a few std::variate_generator<> (like normal) have their
|
|
// own state which would need a reset as well to guarantee identical
|
|
// sequence of numbers, e.g. via myrand.distribution().reset())
|
|
global_rng.seed(seed ^ time(nullptr));
|
|
}
|
|
};
|
|
|
|
RandomNumberGenerator& GetTheRandomNumberGenerator()
|
|
{
|
|
static RandomNumberGenerator RANDOM;
|
|
return RANDOM;
|
|
}
|
|
}
|
|
|
|
void reseed() { GetTheRandomNumberGenerator().reseed(); }
|
|
|
|
// uniform ints [a,b] distribution
|
|
int uniform_int_distribution(int a, int b)
|
|
{
|
|
std::uniform_int_distribution<int> dist(a, b);
|
|
auto& gen = GetTheRandomNumberGenerator();
|
|
std::scoped_lock<std::mutex> g(gen.mutex);
|
|
return dist(gen.global_rng);
|
|
}
|
|
|
|
// uniform ints [a,b] distribution
|
|
unsigned int uniform_uint_distribution(unsigned int a, unsigned int b)
|
|
{
|
|
std::uniform_int_distribution<unsigned int> dist(a, b);
|
|
auto& gen = GetTheRandomNumberGenerator();
|
|
std::scoped_lock<std::mutex> g(gen.mutex);
|
|
return dist(gen.global_rng);
|
|
}
|
|
|
|
// uniform size_t [a,b] distribution
|
|
size_t uniform_size_distribution(size_t a, size_t b)
|
|
{
|
|
std::uniform_int_distribution<size_t> dist(a, b);
|
|
auto& gen = GetTheRandomNumberGenerator();
|
|
std::scoped_lock<std::mutex> g(gen.mutex);
|
|
return dist(gen.global_rng);
|
|
}
|
|
|
|
// uniform size_t [a,b) distribution
|
|
double uniform_real_distribution(double a, double b)
|
|
{
|
|
assert(a < b);
|
|
std::uniform_real_distribution<double> dist(a, b);
|
|
auto& gen = GetTheRandomNumberGenerator();
|
|
std::scoped_lock<std::mutex> g(gen.mutex);
|
|
return dist(gen.global_rng);
|
|
}
|
|
|
|
} // namespace
|
|
|
|
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|