Chris@16: //
Chris@16: // ssl/detail/openssl_init.hpp
Chris@16: // ~~~~~~~~~~~~~~~~~~~~~~~~~~~
Chris@16: //
Chris@101: // Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: 
Chris@16: #ifndef BOOST_ASIO_SSL_DETAIL_OPENSSL_INIT_HPP
Chris@16: #define BOOST_ASIO_SSL_DETAIL_OPENSSL_INIT_HPP
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: # pragma once
Chris@16: #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: 
Chris@16: #include <boost/asio/detail/config.hpp>
Chris@16: #include <cstring>
Chris@16: #include <boost/asio/detail/noncopyable.hpp>
Chris@16: #include <boost/asio/detail/shared_ptr.hpp>
Chris@16: #include <boost/asio/ssl/detail/openssl_types.hpp>
Chris@16: 
Chris@16: #include <boost/asio/detail/push_options.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace asio {
Chris@16: namespace ssl {
Chris@16: namespace detail {
Chris@16: 
Chris@16: class openssl_init_base
Chris@16:   : private noncopyable
Chris@16: {
Chris@16: protected:
Chris@16:   // Class that performs the actual initialisation.
Chris@16:   class do_init;
Chris@16: 
Chris@16:   // Helper function to manage a do_init singleton. The static instance of the
Chris@16:   // openssl_init object ensures that this function is always called before
Chris@16:   // main, and therefore before any other threads can get started. The do_init
Chris@16:   // instance must be static in this function to ensure that it gets
Chris@16:   // initialised before any other global objects try to use it.
Chris@16:   BOOST_ASIO_DECL static boost::asio::detail::shared_ptr<do_init> instance();
Chris@16: 
Chris@16: #if !defined(SSL_OP_NO_COMPRESSION) \
Chris@16:   && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
Chris@16:   // Get an empty stack of compression methods, to be used when disabling
Chris@16:   // compression.
Chris@16:   BOOST_ASIO_DECL static STACK_OF(SSL_COMP)* get_null_compression_methods();
Chris@16: #endif // !defined(SSL_OP_NO_COMPRESSION)
Chris@16:        // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
Chris@16: };
Chris@16: 
Chris@16: template <bool Do_Init = true>
Chris@16: class openssl_init : private openssl_init_base
Chris@16: {
Chris@16: public:
Chris@16:   // Constructor.
Chris@16:   openssl_init()
Chris@16:     : ref_(instance())
Chris@16:   {
Chris@16:     using namespace std; // For memmove.
Chris@16: 
Chris@16:     // Ensure openssl_init::instance_ is linked in.
Chris@16:     openssl_init* tmp = &instance_;
Chris@16:     memmove(&tmp, &tmp, sizeof(openssl_init*));
Chris@16:   }
Chris@16: 
Chris@16:   // Destructor.
Chris@16:   ~openssl_init()
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16: #if !defined(SSL_OP_NO_COMPRESSION) \
Chris@16:   && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
Chris@16:   using openssl_init_base::get_null_compression_methods;
Chris@16: #endif // !defined(SSL_OP_NO_COMPRESSION)
Chris@16:        // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
Chris@16: 
Chris@16: private:
Chris@16:   // Instance to force initialisation of openssl at global scope.
Chris@16:   static openssl_init instance_;
Chris@16: 
Chris@16:   // Reference to singleton do_init object to ensure that openssl does not get
Chris@16:   // cleaned up until the last user has finished with it.
Chris@16:   boost::asio::detail::shared_ptr<do_init> ref_;
Chris@16: };
Chris@16: 
Chris@16: template <bool Do_Init>
Chris@16: openssl_init<Do_Init> openssl_init<Do_Init>::instance_;
Chris@16: 
Chris@16: } // namespace detail
Chris@16: } // namespace ssl
Chris@16: } // namespace asio
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #include <boost/asio/detail/pop_options.hpp>
Chris@16: 
Chris@16: #if defined(BOOST_ASIO_HEADER_ONLY)
Chris@16: # include <boost/asio/ssl/detail/impl/openssl_init.ipp>
Chris@16: #endif // defined(BOOST_ASIO_HEADER_ONLY)
Chris@16: 
Chris@16: #endif // BOOST_ASIO_SSL_DETAIL_OPENSSL_INIT_HPP