Chris@16: // Boost.Signals2 library
Chris@16: 
Chris@16: // Copyright Douglas Gregor 2001-2004.
Chris@16: // Copyright Frank Mori Hess 2007-2008.
Chris@16: // Use, modification and
Chris@16: // distribution is subject to the Boost Software License, Version
Chris@16: // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: // For more information, see http://www.boost.org
Chris@16: 
Chris@16: #ifndef BOOST_SIGNALS2_SLOT_CALL_ITERATOR_HPP
Chris@16: #define BOOST_SIGNALS2_SLOT_CALL_ITERATOR_HPP
Chris@16: 
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <boost/aligned_storage.hpp>
Chris@16: #include <boost/iterator/iterator_facade.hpp>
Chris@16: #include <boost/optional.hpp>
Chris@16: #include <boost/scoped_ptr.hpp>
Chris@16: #include <boost/signals2/connection.hpp>
Chris@16: #include <boost/signals2/slot_base.hpp>
Chris@16: #include <boost/signals2/detail/auto_buffer.hpp>
Chris@16: #include <boost/signals2/detail/unique_lock.hpp>
Chris@16: #include <boost/weak_ptr.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16:   namespace signals2 {
Chris@16:     namespace detail {
Chris@16:       template<typename ResultType, typename Function>
Chris@16:         class slot_call_iterator_cache
Chris@16:       {
Chris@16:       public:
Chris@16:         slot_call_iterator_cache(const Function &f_arg):
Chris@16:           f(f_arg),
Chris@16:           connected_slot_count(0),
Chris@16:           disconnected_slot_count(0)
Chris@16:         {}
Chris@16:         optional<ResultType> result;
Chris@16:         typedef auto_buffer<void_shared_ptr_variant, store_n_objects<10> > tracked_ptrs_type;
Chris@16:         tracked_ptrs_type tracked_ptrs;
Chris@16:         Function f;
Chris@16:         unsigned connected_slot_count;
Chris@16:         unsigned disconnected_slot_count;
Chris@16:       };
Chris@16: 
Chris@16:       // Generates a slot call iterator. Essentially, this is an iterator that:
Chris@16:       //   - skips over disconnected slots in the underlying list
Chris@16:       //   - calls the connected slots when dereferenced
Chris@16:       //   - caches the result of calling the slots
Chris@16:       template<typename Function, typename Iterator, typename ConnectionBody>
Chris@16:       class slot_call_iterator_t
Chris@16:         : public boost::iterator_facade<slot_call_iterator_t<Function, Iterator, ConnectionBody>,
Chris@16:         typename Function::result_type,
Chris@16:         boost::single_pass_traversal_tag,
Chris@16:         typename Function::result_type const&>
Chris@16:       {
Chris@16:         typedef boost::iterator_facade<slot_call_iterator_t<Function, Iterator, ConnectionBody>,
Chris@16:           typename Function::result_type,
Chris@16:           boost::single_pass_traversal_tag,
Chris@16:           typename Function::result_type const&>
Chris@16:         inherited;
Chris@16: 
Chris@16:         typedef typename Function::result_type result_type;
Chris@16: 
Chris@16:         friend class boost::iterator_core_access;
Chris@16: 
Chris@16:       public:
Chris@16:         slot_call_iterator_t(Iterator iter_in, Iterator end_in,
Chris@16:           slot_call_iterator_cache<result_type, Function> &c):
Chris@16:           iter(iter_in), end(end_in),
Chris@16:           cache(&c), callable_iter(end_in)
Chris@16:         {
Chris@16:           lock_next_callable();
Chris@16:         }
Chris@16: 
Chris@16:         typename inherited::reference
Chris@16:         dereference() const
Chris@16:         {
Chris@16:           if (!cache->result) {
Chris@16:             try
Chris@16:             {
Chris@16:               cache->result.reset(cache->f(*iter));
Chris@16:             }
Chris@16:             catch(expired_slot &)
Chris@16:             {
Chris@16:               (*iter)->disconnect();
Chris@16:               throw;
Chris@16:             }
Chris@16:           }
Chris@16:           return cache->result.get();
Chris@16:         }
Chris@16: 
Chris@16:         void increment()
Chris@16:         {
Chris@16:           ++iter;
Chris@16:           lock_next_callable();
Chris@16:           cache->result.reset();
Chris@16:         }
Chris@16: 
Chris@16:         bool equal(const slot_call_iterator_t& other) const
Chris@16:         {
Chris@16:           return iter == other.iter;
Chris@16:         }
Chris@16: 
Chris@16:       private:
Chris@16:         typedef unique_lock<connection_body_base> lock_type;
Chris@16: 
Chris@16:         void lock_next_callable() const
Chris@16:         {
Chris@16:           if(iter == callable_iter)
Chris@16:           {
Chris@16:             return;
Chris@16:           }
Chris@16:           for(;iter != end; ++iter)
Chris@16:           {
Chris@101:             cache->tracked_ptrs.clear();
Chris@16:             lock_type lock(**iter);
Chris@16:             (*iter)->nolock_grab_tracked_objects(std::back_inserter(cache->tracked_ptrs));
Chris@16:             if((*iter)->nolock_nograb_connected())
Chris@16:             {
Chris@16:               ++cache->connected_slot_count;
Chris@16:             }else
Chris@16:             {
Chris@16:               ++cache->disconnected_slot_count;
Chris@16:             }
Chris@16:             if((*iter)->nolock_nograb_blocked() == false)
Chris@16:             {
Chris@16:               callable_iter = iter;
Chris@16:               break;
Chris@16:             }
Chris@16:           }
Chris@16:           if(iter == end)
Chris@16:           {
Chris@16:             callable_iter = end;
Chris@16:           }
Chris@16:         }
Chris@16: 
Chris@16:         mutable Iterator iter;
Chris@16:         Iterator end;
Chris@16:         slot_call_iterator_cache<result_type, Function> *cache;
Chris@16:         mutable Iterator callable_iter;
Chris@16:       };
Chris@16:     } // end namespace detail
Chris@16:   } // end namespace BOOST_SIGNALS_NAMESPACE
Chris@16: } // end namespace boost
Chris@16: 
Chris@16: #endif // BOOST_SIGNALS2_SLOT_CALL_ITERATOR_HPP