1// Boost.Signals library
2
3// Copyright Douglas Gregor 2001-2004. Use, modification and
4// distribution is subject to the Boost Software License, Version
5// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
6// http://www.boost.org/LICENSE_1_0.txt)
7
8// For more information, see http://www.boost.org
9
10#ifndef BOOST_SIGNALS_SLOT_HEADER
11#define BOOST_SIGNALS_SLOT_HEADER
12
13#include <boost/signals/detail/signals_common.hpp>
14#include <boost/signals/connection.hpp>
15#include <boost/signals/trackable.hpp>
16#include <boost/visit_each.hpp>
17#include <boost/shared_ptr.hpp>
18#include <cassert>
19
20#ifdef BOOST_HAS_ABI_HEADERS
21# include BOOST_ABI_PREFIX
22#endif
23
24namespace boost {
25 namespace BOOST_SIGNALS_NAMESPACE {
26 namespace detail {
27 class BOOST_SIGNALS_DECL slot_base {
28 // We would have to enumerate all of the signalN classes here as
29 // friends to make this private (as it otherwise should be). We can't
30 // name all of them because we don't know how many there are.
31 public:
32 struct data_t {
33 std::vector<const trackable*> bound_objects;
34 connection watch_bound_objects;
35 };
36 shared_ptr<data_t> get_data() const { return data; }
37
38 // Get the set of bound objects
39 std::vector<const trackable*>& get_bound_objects() const
40 { return data->bound_objects; }
41
42 // Determine if this slot is still "active", i.e., all of the bound
43 // objects still exist
44 bool is_active() const
45 { return data->watch_bound_objects.connected(); }
46
47 protected:
48 // Create a connection for this slot
49 void create_connection();
50
51 shared_ptr<data_t> data;
52
53 private:
54 static void bound_object_destructed(void*, void*) {}
55 };
56 } // end namespace detail
57
58 // Get the slot so that it can be copied
59 template<typename F>
60 reference_wrapper<const F>
61 get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::signal_tag)
62 { return reference_wrapper<const F>(f); }
63
64 template<typename F>
65 const F&
66 get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::reference_tag)
67 { return f; }
68
69 template<typename F>
70 const F&
71 get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::value_tag)
72 { return f; }
73
74 // Get the slot so that it can be inspected for trackable objects
75 template<typename F>
76 const F&
77 get_inspectable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::signal_tag)
78 { return f; }
79
80 template<typename F>
81 const F&
82 get_inspectable_slot(const reference_wrapper<F>& f, BOOST_SIGNALS_NAMESPACE::detail::reference_tag)
83 { return f.get(); }
84
85 template<typename F>
86 const F&
87 get_inspectable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::value_tag)
88 { return f; }
89
90 // Determines the type of the slot - is it a signal, a reference to a
91 // slot or just a normal slot.
92 template<typename F>
93 typename BOOST_SIGNALS_NAMESPACE::detail::get_slot_tag<F>::type
94 tag_type(const F&)
95 {
96 typedef typename BOOST_SIGNALS_NAMESPACE::detail::get_slot_tag<F>::type
97 the_tag_type;
98 the_tag_type tag = the_tag_type();
99 return tag;
100 }
101
102 } // end namespace BOOST_SIGNALS_NAMESPACE
103
104 template<typename SlotFunction>
105 class slot : public BOOST_SIGNALS_NAMESPACE::detail::slot_base {
106 typedef BOOST_SIGNALS_NAMESPACE::detail::slot_base inherited;
107 typedef typename inherited::data_t data_t;
108
109 public:
110 template<typename F>
111 slot(const F& f) : slot_function(BOOST_SIGNALS_NAMESPACE::get_invocable_slot(f, BOOST_SIGNALS_NAMESPACE::tag_type(f)))
112 {
113 this->data.reset(new data_t);
114
115 // Visit each of the bound objects and store them for later use
116 // An exception thrown here will allow the basic_connection to be
117 // destroyed when this goes out of scope, and no other connections
118 // have been made.
119 BOOST_SIGNALS_NAMESPACE::detail::bound_objects_visitor
120 do_bind(this->data->bound_objects);
121 visit_each(do_bind,
122 BOOST_SIGNALS_NAMESPACE::get_inspectable_slot
123 (f, BOOST_SIGNALS_NAMESPACE::tag_type(f)));
124 create_connection();
125 }
126
127#ifdef __BORLANDC__
128 template<typename F>
129 slot(F* f) : slot_function(f)
130 {
131 this->data.reset(new data_t);
132 create_connection();
133 }
134#endif // __BORLANDC__
135
136 // We would have to enumerate all of the signalN classes here as friends
137 // to make this private (as it otherwise should be). We can't name all of
138 // them because we don't know how many there are.
139 public:
140 // Get the slot function to call the actual slot
141 const SlotFunction& get_slot_function() const { return slot_function; }
142
143 void release() const { data->watch_bound_objects.set_controlling(false); }
144
145 private:
146 slot(); // no default constructor
147 slot& operator=(const slot&); // no assignment operator
148
149 SlotFunction slot_function;
150 };
151} // end namespace boost
152
153#ifdef BOOST_HAS_ABI_HEADERS
154# include BOOST_ABI_SUFFIX
155#endif
156
157#endif // BOOST_SIGNALS_SLOT_HEADER
158

source code of boost/boost/signals/slot.hpp