text: //
  // ssl/detail/verify_callback.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2017 Christopher M. Kohlhoff (chris at kohlhoff dot com)
  //
  // Distributed under the Boost Software License, Version 1.0. (See accompanying
  // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  //
  
  #ifndef ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
  #define ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include "asio/detail/config.hpp"
  
  #include "asio/ssl/verify_context.hpp"
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  namespace ssl {
  namespace detail {
  
  class verify_callback_base
  {
  public:
    virtual ~verify_callback_base()
    {
    }
  
    virtual bool call(bool preverified, verify_context& ctx) = 0;
  };
  
  template <typename VerifyCallback>
  class verify_callback : public verify_callback_base
  {
  public:
    explicit verify_callback(VerifyCallback callback)
      : callback_(callback)
    {
    }
  
    virtual bool call(bool preverified, verify_context& ctx)
    {
      return callback_(preverified, ctx);
    }
  
  private:
    VerifyCallback callback_;
  };
  
  } // namespace detail
  } // namespace ssl
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #endif // ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
  