Mercurial > hg > CbC > CbC_gcc
view libstdc++-v3/testsuite/26_numerics/random/random_device/94087.cc @ 152:2b5abeee2509
update gcc11
author | anatofuz |
---|---|
date | Mon, 25 May 2020 07:50:57 +0900 |
parents | |
children |
line wrap: on
line source
// Copyright (C) 2020 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library 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 3, or (at your option) // any later version. // This library 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 library; see the file COPYING3. If not see // <http://www.gnu.org/licenses/>. // { dg-do run } // { dg-options "-pthread" } // { dg-require-effective-target c++11 } // { dg-require-effective-target pthread } // { dg-require-gthreads "" } #include <random> #include <memory> #include <thread> #include <cstdio> bool random_device_available(const char* token) noexcept { try { std::random_device dev(token); return true; } catch (...) { std::printf("random_device(\"%s\") not available\n", token); return false; } } void read_random_device(const char* token, int iterations) { std::random_device dev(token); for (int i = 0; i != iterations; ++i) (void) dev(); } int main() { std::thread workers[8]; // N.B. don't test /dev/random as it might block, and /dev/urandom // "can incur an appreciable delay when requesting large amounts of data". for (const char* dev : { "default", "rdrand", "rdseed", "rand_s" }) { if (random_device_available(dev)) { for (auto& w : workers) w = std::thread{read_random_device, dev, 1000}; for (auto& w : workers) w.join(); } } }