mirror of
https://github.com/d47081/qBittorrent.git
synced 2025-01-16 01:30:09 +00:00
76 lines
2.8 KiB
C++
76 lines
2.8 KiB
C++
/*
|
|
* Bittorrent Client using Qt and libtorrent.
|
|
* Copyright (C) 2017 Mike Tzou
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*
|
|
* In addition, as a special exception, the copyright holders give permission to
|
|
* link this program with the OpenSSL project's "OpenSSL" library (or with
|
|
* modified versions of it that use the same license as the "OpenSSL" library),
|
|
* and distribute the linked executables. You must obey the GNU General Public
|
|
* License in all respects for all of the code used other than "OpenSSL". If you
|
|
* modify file(s), you may extend this exception to your version of the file(s),
|
|
* but you are not obligated to do so. If you do not wish to do so, delete this
|
|
* exception statement from your version.
|
|
*
|
|
*/
|
|
|
|
#include "random.h"
|
|
|
|
#include <cassert>
|
|
#include <chrono>
|
|
#include <random>
|
|
|
|
#include <QtGlobal>
|
|
|
|
#ifdef Q_OS_MAC
|
|
#include <QThreadStorage>
|
|
#endif
|
|
|
|
// on some platform `std::random_device` may generate the same number sequence
|
|
static bool hasTrueRandomDevice{ std::random_device{}() != std::random_device{}() };
|
|
|
|
uint32_t Utils::Random::rand(const uint32_t min, const uint32_t max)
|
|
{
|
|
#ifdef Q_OS_MAC // workaround for Apple xcode: https://stackoverflow.com/a/29929949
|
|
static QThreadStorage<std::mt19937> generator;
|
|
if (!generator.hasLocalData())
|
|
generator.localData().seed(
|
|
hasTrueRandomDevice
|
|
? std::random_device{}()
|
|
: (std::random_device::result_type) std::chrono::system_clock::now().time_since_epoch().count()
|
|
);
|
|
#else
|
|
static thread_local std::mt19937 generator{
|
|
hasTrueRandomDevice
|
|
? std::random_device{}()
|
|
: static_cast<std::random_device::result_type>(std::chrono::system_clock::now().time_since_epoch().count())
|
|
};
|
|
#endif
|
|
|
|
// better replacement for `std::rand`, don't use this for real cryptography application
|
|
// min <= returned_value <= max
|
|
assert(min <= max);
|
|
|
|
// new distribution is cheap: http://stackoverflow.com/a/19036349
|
|
std::uniform_int_distribution<uint32_t> uniform(min, max);
|
|
|
|
#ifdef Q_OS_MAC
|
|
return uniform(generator.localData());
|
|
#else
|
|
return uniform(generator);
|
|
#endif
|
|
}
|