beacon/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 BEACON_signal_base_H
   8 #define BEACON_signal_base_H
   9
  10 #include <beacon/event_loop.hpp>
  11 #include <beacon/intrusive_ptr.hpp>
  12 #include <beacon/reference_countable.hpp>
  13 #include <beacon/detail/slot.hpp>
  14 #include <beacon/trackable.hpp>
  15 #include <beacon/detail/connection_impl_base.hpp>
  16 #include <beacon/detail/quick_wait.hpp>
  17 #include <list>
  18 #include <utility>
  19
  20 extern "C" {
  21 #include <atomic_ops.h>
  22 }
  23
  24 namespace beacon {
  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             slot_base * slot;
  40             intrusive_ptr<connection_impl_base> connection;
  41             event_loop * loop;
  42
  43             slot_list_item() : slot(0), connection(), loop(0) {}
  44         };
  45         typedef std::list<slot_list_item> slot_list_type;
  46
  47         /**
  48          * Disconnects all slots from this signal.
  49          */
  50         void clear();
  51
  52     protected:
  53
  54         signal_base() : _slots(), _slots_guard(AO_TS_INITIALIZER) {}
  55
  56         /**
  57          * Initializes the connection.
  58          */
  59         intrusive_ptr<connection_impl_base> do_connect(slot_base * slot, trackable * obj);
  60
  61         /**
  62          * Removes the connection record identified by the iterator from the
  63          * slot list.
  64          */
  65         void do_disconnect(slot_list_type::iterator pos);
  66
  67         /**
  68          * Returns a copy of the slot list as it was at the time
  69          * of the call. This operation is thread safe as it made sure
  70          * that no modifications are possible while making this copy.
  71          */
  72         slot_list_type get_slots_copy();
  73     private:
  74
  75         slot_list_type _slots;
  76
  77         AO_TS_t _slots_guard;
  78 };
  79
  80 } //namespace detail
  81
  82 } //namespace beacon
  83
  84 #endif