csprng.h

#pragma once
 
#include <mutex>
 
namespace xrpl {
 
class csprng_engine
{
private:
    std::mutex mutex_;
 
public:
    using result_type = std::uint64_t;
 
    csprng_engine(csprng_engine const&) = delete;
    csprng_engine&
    operator=(csprng_engine const&) = delete;
 
    csprng_engine(csprng_engine&&) = delete;
    csprng_engine&
    operator=(csprng_engine&&) = delete;
 
    csprng_engine();
    ~csprng_engine();
 
    void
    mix_entropy(void* buffer = nullptr, std::size_t count = 0);
 
    result_type
    operator()();
 
    void
    operator()(void* ptr, std::size_t count);
 
    /* The smallest possible value that can be returned */
    static constexpr result_type
    min()
    {
        return std::numeric_limits<result_type>::min();
    }
 
    /* The largest possible value that can be returned */
    static constexpr result_type
    max()
    {
        return std::numeric_limits<result_type>::max();
    }
};
 
csprng_engine&
crypto_prng();
 
}  // namespace xrpl