From bc524d70253a4ab2fe40c3ca3e5666e267c0a4d1 Mon Sep 17 00:00:00 2001 From: Lexi Winter Date: Sun, 29 Jun 2025 19:25:29 +0100 Subject: import catch2 3.8.1 --- .../internal/catch_random_number_generator.hpp | 59 ++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 src/catch2/internal/catch_random_number_generator.hpp (limited to 'src/catch2/internal/catch_random_number_generator.hpp') diff --git a/src/catch2/internal/catch_random_number_generator.hpp b/src/catch2/internal/catch_random_number_generator.hpp new file mode 100644 index 0000000..e4129be --- /dev/null +++ b/src/catch2/internal/catch_random_number_generator.hpp @@ -0,0 +1,59 @@ + +// Copyright Catch2 Authors +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE.txt or copy at +// https://www.boost.org/LICENSE_1_0.txt) + +// SPDX-License-Identifier: BSL-1.0 +#ifndef CATCH_RANDOM_NUMBER_GENERATOR_HPP_INCLUDED +#define CATCH_RANDOM_NUMBER_GENERATOR_HPP_INCLUDED + +#include + +namespace Catch { + + // This is a simple implementation of C++11 Uniform Random Number + // Generator. It does not provide all operators, because Catch2 + // does not use it, but it should behave as expected inside stdlib's + // distributions. + // The implementation is based on the PCG family (http://pcg-random.org) + class SimplePcg32 { + using state_type = std::uint64_t; + public: + using result_type = std::uint32_t; + static constexpr result_type (min)() { + return 0; + } + static constexpr result_type (max)() { + return static_cast(-1); + } + + // Provide some default initial state for the default constructor + SimplePcg32():SimplePcg32(0xed743cc4U) {} + + explicit SimplePcg32(result_type seed_); + + void seed(result_type seed_); + void discard(uint64_t skip); + + result_type operator()(); + + private: + friend bool operator==(SimplePcg32 const& lhs, SimplePcg32 const& rhs); + friend bool operator!=(SimplePcg32 const& lhs, SimplePcg32 const& rhs); + + // In theory we also need operator<< and operator>> + // In practice we do not use them, so we will skip them for now + + + std::uint64_t m_state; + // This part of the state determines which "stream" of the numbers + // is chosen -- we take it as a constant for Catch2, so we only + // need to deal with seeding the main state. + // Picked by reading 8 bytes from `/dev/random` :-) + static const std::uint64_t s_inc = (0x13ed0cc53f939476ULL << 1ULL) | 1ULL; + }; + +} // end namespace Catch + +#endif // CATCH_RANDOM_NUMBER_GENERATOR_HPP_INCLUDED -- cgit v1.2.3