src/beacons/detail/signal_base.hpp

   1 /**
   2  * beacon
   3  * Author: Lukas Krejci <krejci.l@centrum.cz>, (C) 2008
   4  * Copyright: See COPYING file that comes with this distribution
   5  */
   6
   7 #ifndef BEACONS_signal_base_H
   8 #define BEACONS_signal_base_H
   9
  10 #include <beacons/event_queue.hpp>
  11 #include <beacons/intrusive_ptr.hpp>
  12 #include <beacons/reference_countable.hpp>
  13 #include <beacons/detail/slot.hpp>
  14 #include <beacons/trackable.hpp>
  15 #include <beacons/detail/connection_impl_base.hpp>
  16 #include <beacons/detail/quick_wait.hpp>
  17 #include <list>
  18 #include <utility>
  19
  20 extern "C" {
  21 #include <atomic_ops.h>
  22 }
  23
  24 namespace beacons {
  25
  26 namespace detail {
  27
  28 //forward decl
  29 class connection_impl;
  30
  31 class signal_base : public reference_countable {
  32     friend class connection_impl;
  33     public:
  34
  35         //we represent the slot as just a slot_base * so that this
  36         //class doesn't have to be templated. The subclasses will
  37         //know what concrete slot type to cast it to...
  38         struct slot_list_item {
  39             intrusive_ptr<slot_base> slot;
  40             intrusive_ptr<connection_impl_base> connection;
  41             event_queue * queue;
  42
  43             slot_list_item() : slot(0), connection(), queue(0) {}
  44         };
  45         typedef std::list<slot_list_item> slot_list_type;
  46
  47         ~signal_base() {
  48             clear();
  49         }
  50
  51         /**
  52          * Disconnects all slots from this signal.
  53          */
  54         void clear();
  55
  56     protected:
  57
  58         signal_base() : _slots(), _slots_guard(AO_TS_INITIALIZER) {}
  59
  60         /**
  61          * Initializes the connection.
  62          */
  63         intrusive_ptr<connection_impl_base> do_connect(intrusive_ptr<slot_base> slot, trackable * obj);
  64
  65         /**
  66          * Initializes the connection.
  67          */
  68         intrusive_ptr<connection_impl_base> do_connect(intrusive_ptr<slot_base> slot, event_queue & queue);
  69
  70         /**
  71          * Removes the connection record identified by the iterator from the
  72          * slot list.
  73          */
  74         void do_disconnect(slot_list_type::iterator pos);
  75
  76         /**
  77          * Returns a copy of the slot list as it was at the time
  78          * of the call. This operation is thread safe as it made sure
  79          * that no modifications are possible while making this copy.
  80          */
  81         slot_list_type get_slots_copy();
  82     private:
  83
  84         intrusive_ptr<connection_impl_base> _init_connection(slot_list_item & item);
  85
  86         slot_list_type _slots;
  87
  88         AO_TS_t _slots_guard;
  89 };
  90
  91 } //namespace detail
  92
  93 } //namespace beacons
  94
  95 #endif