sl@0: // (C) Copyright Jonathan Turkanis 2003.
sl@0: // Distributed under the Boost Software License, Version 1.0. (See accompanying
sl@0: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
sl@0: 
sl@0: // See http://www.boost.org/libs/iostreams for documentation.
sl@0: 
sl@0: #ifndef BOOST_IOSTREAMS_DETAIL_CLOSER_HPP_INCLUDED
sl@0: #define BOOST_IOSTREAMS_DETAIL_CLOSER_HPP_INCLUDED
sl@0: 
sl@0: #if defined(_MSC_VER) && (_MSC_VER >= 1020)
sl@0: # pragma once
sl@0: #endif
sl@0: 
sl@0: #include <exception>                       // exception.
sl@0: #include <boost/iostreams/detail/ios.hpp>  // openmode.
sl@0: #include <boost/iostreams/operations.hpp>  // close
sl@0: #include <boost/iostreams/traits.hpp>      // is_device.
sl@0: #include <boost/mpl/if.hpp>
sl@0: 
sl@0: namespace boost { namespace iostreams { namespace detail {
sl@0: 
sl@0: template<typename T>
sl@0: struct closer {
sl@0:     closer(T& t) : t_(&t) { }
sl@0:     ~closer() { try { t_->close(); } catch (std::exception&) { } }
sl@0:     T* t_;
sl@0: };
sl@0: 
sl@0: template<typename Device>
sl@0: struct external_device_closer {
sl@0:     external_device_closer(Device& dev, BOOST_IOS::openmode which)
sl@0:         : device_(&dev), which_(which),
sl@0:           dummy_(true), nothrow_(dummy_)
sl@0:         { }
sl@0:     external_device_closer(Device& dev, BOOST_IOS::openmode which, bool& nothrow)
sl@0:         : device_(&dev), which_(which), 
sl@0:           dummy_(true), nothrow_(nothrow)
sl@0:         { }
sl@0:     ~external_device_closer() 
sl@0:     { 
sl@0:         try { 
sl@0:             boost::iostreams::close(*device_, which_); 
sl@0:         } catch (...) {
sl@0:             if (!nothrow_) {
sl@0:                 nothrow_ = true;
sl@0:                 throw;
sl@0:             }
sl@0:         } 
sl@0:     }
sl@0:     Device*               device_;
sl@0:     BOOST_IOS::openmode   which_;
sl@0:     bool                  dummy_;
sl@0:     bool&                 nothrow_;
sl@0: };
sl@0: 
sl@0: template<typename Filter, typename Device>
sl@0: struct external_filter_closer {
sl@0:     external_filter_closer(Filter& flt, Device& dev, BOOST_IOS::openmode which)
sl@0:         : filter_(flt), device_(dev), which_(which), 
sl@0:           dummy_(true), nothrow_(dummy_) 
sl@0:         { }
sl@0:     external_filter_closer( Filter& flt, Device& dev, 
sl@0:                             BOOST_IOS::openmode which, bool& nothrow )
sl@0:         : filter_(flt), device_(dev), which_(which), 
sl@0:           dummy_(true), nothrow_(nothrow) 
sl@0:         { }
sl@0:     ~external_filter_closer() 
sl@0:     { 
sl@0:         try { 
sl@0:             boost::iostreams::close(filter_, device_, which_); 
sl@0:         } catch (...) { 
sl@0:             if (!nothrow_) {
sl@0:                 nothrow_ = true;
sl@0:                 throw;
sl@0:             }
sl@0:         } 
sl@0:     }
sl@0:     Filter&               filter_;
sl@0:     Device&               device_;
sl@0:     BOOST_IOS::openmode   which_;
sl@0:     bool                  dummy_;
sl@0:     bool&                 nothrow_;
sl@0: };
sl@0: 
sl@0: template<typename FilterOrDevice, typename DeviceOrDummy = int>
sl@0: struct external_closer_traits {
sl@0:     typedef typename 
sl@0:             mpl::if_<
sl@0:                 is_device<FilterOrDevice>,
sl@0:                 external_device_closer<FilterOrDevice>,
sl@0:                 external_filter_closer<FilterOrDevice, DeviceOrDummy>
sl@0:             >::type type;
sl@0: };
sl@0: 
sl@0: template<typename FilterOrDevice, typename DeviceOrDummy = int>
sl@0: struct external_closer 
sl@0:     : external_closer_traits<FilterOrDevice, DeviceOrDummy>::type
sl@0: { 
sl@0:     typedef typename 
sl@0:             external_closer_traits<
sl@0:                 FilterOrDevice, DeviceOrDummy
sl@0:             >::type base_type;
sl@0:     external_closer(FilterOrDevice& dev, BOOST_IOS::openmode which)
sl@0:         : base_type(dev, which)
sl@0:     { BOOST_STATIC_ASSERT(is_device<FilterOrDevice>::value); };
sl@0:     external_closer( FilterOrDevice& dev, BOOST_IOS::openmode which,
sl@0:                      bool& nothrow )
sl@0:         : base_type(dev, which, nothrow)
sl@0:     { BOOST_STATIC_ASSERT(is_device<FilterOrDevice>::value); };
sl@0:     external_closer( FilterOrDevice& flt, DeviceOrDummy& dev,
sl@0:                      BOOST_IOS::openmode which )
sl@0:         : base_type(flt, dev, which)
sl@0:     { BOOST_STATIC_ASSERT(is_filter<FilterOrDevice>::value); };
sl@0:     external_closer( FilterOrDevice& flt, DeviceOrDummy& dev,
sl@0:                      BOOST_IOS::openmode which, bool& nothrow )
sl@0:         : base_type(flt, dev, which, nothrow)
sl@0:     { BOOST_STATIC_ASSERT(is_filter<FilterOrDevice>::value); };
sl@0: };
sl@0: 
sl@0: } } } // End namespaces detail, iostreams, boost.
sl@0: 
sl@0: #endif // #ifndef BOOST_IOSTREAMS_DETAIL_CLOSER_HPP_INCLUDED