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boost/uuid/detail/random_provider_getentropy.ipp

//
// Copyright (c) 2017 James E. King III
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
//   https://www.boost.org/LICENSE_1_0.txt)
//
// getentropy() capable platforms
//

#include <boost/config.hpp>
#include <boost/throw_exception.hpp>
#include <cerrno>
#include <cstddef>
#include <unistd.h>

namespace boost {
namespace uuids {
namespace detail {

class random_provider_base
{
public:
    //! Obtain entropy and place it into a memory location
    //! \param[in]  buf  the location to write entropy
    //! \param[in]  siz  the number of bytes to acquire
    void get_random_bytes(void *buf, std::size_t siz)
    {
        int res = getentropy(buf, siz);
        if (BOOST_UNLIKELY(-1 == res))
        {
            int err = errno;
            BOOST_THROW_EXCEPTION(entropy_error(err, "getentropy"));
        }
    }
};

} // detail
} // uuids
} // boost