blob: 90909b0f1680e20c8502e1423f5356b05f67f134 [file] [log] [blame] [edit]
/*
* grandom.cc
*
* This file is licensed under the GPLv2 or later
*
* Pseudo-random number generation
*
* Copyright (C) 2012 Fabio D'Urso <fabiodurso@hotmail.it>
* Copyright (C) 2018 Adam Reichold <adam.reichold@t-online.de>
* Copyright (C) 2022 Albert Astals Cid <aacid@kde.org>
*/
#include "grandom.h"
#include <random>
namespace {
auto &grandom_engine()
{
static thread_local std::default_random_engine engine { std::random_device {}() };
return engine;
}
}
void grandom_fill(unsigned char *buff, int size)
{
auto &engine = grandom_engine();
std::uniform_int_distribution<unsigned short> distribution { std::numeric_limits<unsigned char>::min(), std::numeric_limits<unsigned char>::max() };
for (int index = 0; index < size; ++index) {
buff[index] = static_cast<unsigned char>(distribution(engine));
}
}
double grandom_double()
{
auto &engine = grandom_engine();
return std::generate_canonical<double, std::numeric_limits<double>::digits>(engine);
}