1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
/*
Copyright (C) 2009-2012 Paul Davis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef __pbd_signals_h__
#define __pbd_signals_h__
#include <csignal>
#include <list>
#include <map>
#ifdef nil
#undef nil
#endif
#include <glibmm/threads.h>
#include <boost/noncopyable.hpp>
#include <boost/bind.hpp>
#include <boost/bind/protect.hpp>
#include <boost/function.hpp>
#include <boost/enable_shared_from_this.hpp>
#include <boost/optional.hpp>
#include "pbd/libpbd_visibility.h"
#include "pbd/event_loop.h"
#ifndef NDEBUG
#define DEBUG_PBD_SIGNAL_CONNECTIONS
#endif
#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
#include "pbd/stacktrace.h"
#include <iostream>
#endif
namespace PBD {
class LIBPBD_API Connection;
class LIBPBD_API SignalBase
{
public:
SignalBase ()
#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
: _debug_connection (false)
#endif
{}
virtual ~SignalBase () {}
virtual void disconnect (boost::shared_ptr<Connection>) = 0;
#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
void set_debug_connection (bool yn) { _debug_connection = yn; }
#endif
protected:
mutable Glib::Threads::Mutex _mutex;
#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
bool _debug_connection;
#endif
};
class LIBPBD_API Connection : public boost::enable_shared_from_this<Connection>
{
public:
Connection (SignalBase* b, PBD::EventLoop::InvalidationRecord* ir) : _signal (b), _invalidation_record (ir)
{
if (_invalidation_record) {
_invalidation_record->ref ();
}
}
void disconnect ()
{
Glib::Threads::Mutex::Lock lm (_mutex);
if (_signal) {
_signal->disconnect (shared_from_this ());
_signal = 0;
}
}
void disconnected ()
{
if (_invalidation_record) {
_invalidation_record->unref ();
}
}
void signal_going_away ()
{
Glib::Threads::Mutex::Lock lm (_mutex);
if (_invalidation_record) {
_invalidation_record->unref ();
}
_signal = 0;
}
private:
Glib::Threads::Mutex _mutex;
SignalBase* _signal;
PBD::EventLoop::InvalidationRecord* _invalidation_record;
};
template<typename R>
class /*LIBPBD_API*/ OptionalLastValue
{
public:
typedef boost::optional<R> result_type;
template <typename Iter>
result_type operator() (Iter first, Iter last) const {
result_type r;
while (first != last) {
r = *first;
++first;
}
return r;
}
};
typedef boost::shared_ptr<Connection> UnscopedConnection;
class LIBPBD_API ScopedConnection
{
public:
ScopedConnection () {}
ScopedConnection (UnscopedConnection c) : _c (c) {}
~ScopedConnection () {
disconnect ();
}
void disconnect ()
{
if (_c) {
_c->disconnect ();
}
}
ScopedConnection& operator= (UnscopedConnection const & o)
{
if (_c == o) {
return *this;
}
disconnect ();
_c = o;
return *this;
}
private:
UnscopedConnection _c;
};
class LIBPBD_API ScopedConnectionList : public boost::noncopyable
{
public:
ScopedConnectionList();
virtual ~ScopedConnectionList ();
void add_connection (const UnscopedConnection& c);
void drop_connections ();
private:
/* this class is not copyable */
ScopedConnectionList(const ScopedConnectionList&);
/* Even though our signals code is thread-safe, this additional list of
scoped connections needs to be protected in 2 cases:
(1) (unlikely) we make a connection involving a callback on the
same object from 2 threads. (wouldn't that just be appalling
programming style?)
(2) where we are dropping connections in one thread and adding
one from another.
*/
Glib::Threads::Mutex _scoped_connection_lock;
typedef std::list<ScopedConnection*> ConnectionList;
ConnectionList _scoped_connection_list;
};
#include "pbd/signals_generated.h"
} /* namespace */
#endif /* __pbd_signals_h__ */
|
