File: qiomanager.cc

package info (click to toggle)
arts 1.5.9-3
  • links: PTS, VCS
  • area: main
  • in suites: squeeze
  • size: 8,436 kB
  • ctags: 9,848
  • sloc: ansic: 44,670; cpp: 33,776; sh: 10,486; perl: 3,470; makefile: 372; yacc: 347; lex: 160
file content (299 lines) | stat: -rw-r--r-- 6,677 bytes parent folder | download | duplicates (3)
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
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
    /*

    Copyright (C) 1999-2001 Stefan Westerfeld
                            stefan@space.twc.de

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
  
    This library 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
    Library General Public License for more details.
   
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.

    */

#include "qiomanager.h"
#include "qiomanager_p.h"
#include <qsocketnotifier.h>
#include <qapplication.h>
#include "debug.h"
#include "dispatcher.h"
#include "thread.h"

using namespace std;
using namespace Arts;

/* 
 * Collected incompatibilities of QIOManager (compared against StdIOManager):
 *
 * - StdIOManager catches up timers (i.e. if a 100ms timer hasn't been
 *   notified for half a second, it will get notified five times to
 *   catch up the lost time
 * - StdIOManager is able to watch the same filedescriptor twice for reading
 * - StdIOManager sends notifications soon after they have been produced,
 *   whereas we use a hackish 50ms timer to deliver them
 */

/*
 * Fallback for the case where we should perform blocking
 */
namespace Arts {
class QIOManagerBlocking : public StdIOManager {
public:
	void setLevel(int newLevel) { level = newLevel; }
};
}

/*
 * QIOManager is a singleton (or at least supposed to be used only once at
 * most, and the behaviour would pretty undefined if you violate this), so we
 * use static variables for private data here.
 */
static int qioLevel;
static QIOManager *qioManager = 0;
static QIOManagerBlocking *qioManagerBlocking = 0;
static bool qioBlocking;

/*
 * QIOWatch:
 */
QIOWatch::QIOWatch(int fd, int type, IONotify *notify,
	QSocketNotifier::Type qtype, bool reentrant)
	: _fd(fd), _type(type), _client(notify), _reentrant(reentrant)
{
	qsocketnotify = new QSocketNotifier(fd,qtype,this);
	connect(qsocketnotify,SIGNAL(activated(int)),this,SLOT(notify(int)));
}

void QIOWatch::notify(int socket)
{
	arts_assert(socket == _fd);
	qioManager->dispatch(this);
}

/*
 * QTimeWatch:
 */
QTimeWatch::QTimeWatch(int milliseconds, TimeNotify *notify)
{
	timer = new QTimer(this);
	connect( timer, SIGNAL(timeout()), this, SLOT(notify()) );
	timer->start(milliseconds);
	_client = notify;
}

void QTimeWatch::notify()
{
	qioManager->dispatch(this);
}

/*
 * Handle NotificationManager::the()->run() from time to time
 */
namespace Arts {

class HandleNotifications : public TimeNotify {
public:
	void notifyTime()
	{
		Arts::Dispatcher::the()->ioManager()->removeTimer(this);
		NotificationManager::the()->run();
		delete this;
	}
};
}

/*
 * QIOManager:
 */
QIOManager::QIOManager()
{
	assert(!qioManager);
	qioManager = this;
	qioLevel = 0;
	qioBlocking = true;
	qioManagerBlocking = new QIOManagerBlocking();
}

QIOManager::~QIOManager()
{
	assert(qioManager);
	qioManager = 0;

	delete qioManagerBlocking;
	qioManagerBlocking = 0;
}

void QIOManager::processOneEvent(bool blocking)
{
	assert(SystemThreads::the()->isMainThread());

	if(qioBlocking)
	{
		qioLevel++;
		if(qioLevel == 1)
			Dispatcher::lock();

		/*
		 * we explicitly take the level to qioManagerBlocking, so that it
		 * will process reentrant watchFDs only
		 */
		qioManagerBlocking->setLevel(qioLevel);
		qioManagerBlocking->processOneEvent(blocking);

		if(qioLevel == 1)
			Dispatcher::unlock();
		qioLevel--;
	}
	else
	{
		if(blocking)
			qApp->processOneEvent();
		else
			qApp->processEvents(0);
	}
}

void QIOManager::run()
{
	arts_warning("QIOManager::run() not implemented.");
}

void QIOManager::terminate()
{
	arts_warning("QIOManager::terminate() not implemented.");
}

void QIOManager::watchFD(int fd, int types, IONotify *notify)
{
	bool r = (types & IOType::reentrant) != 0;

	if(types & IOType::read)
	{
		fdList.push_back(
			new QIOWatch(fd, IOType::read, notify, QSocketNotifier::Read, r)
		);
	}
	if(types & IOType::write)
	{
		fdList.push_back(
			new QIOWatch(fd, IOType::write, notify, QSocketNotifier::Write, r)
		);
	}
	if(types & IOType::except)
	{
		fdList.push_back(
			new QIOWatch(fd, IOType::except, notify, QSocketNotifier::Exception,
						 r)
		);
	}
	if(r) qioManagerBlocking->watchFD(fd, types, notify);
}

void QIOManager::remove(IONotify *notify, int types)
{
	list<QIOWatch *>::iterator i;

	i = fdList.begin();
	while(i != fdList.end())
	{
		QIOWatch *w = *i;

		if(w->type() & types && w->client() == notify)
		{
			delete w;
			fdList.erase(i);
			i = fdList.begin();
		}
		else i++;
	}
	qioManagerBlocking->remove(notify, types);
}

void QIOManager::addTimer(int milliseconds, TimeNotify *notify)
{
	if (milliseconds == -1 && notify == 0)
	{
		// HACK: in order to not add a virtual function to IOManager we're calling addTimer with
		// magic values. This call tells the ioManager that notifications are pending and
		// NotificationManager::run() should get called soon.
		notify = new HandleNotifications();
		milliseconds = 0;
	}
	timeList.push_back(new QTimeWatch(milliseconds,notify));
}

void QIOManager::removeTimer(TimeNotify *notify)
{
	list<QTimeWatch *>::iterator i;

	i = timeList.begin();
	while(i != timeList.end())
	{
		QTimeWatch *w = *i;

		if(w->client() == notify)
		{
			delete w;
			timeList.erase(i);
			i = timeList.begin();
		}
		else i++;
	}
}

void QIOManager::dispatch(QIOWatch *ioWatch)
{
	qioLevel++;
	if(qioLevel == 1)
		Dispatcher::lock();

	/*
	 * FIXME: there is main loop pollution for (qioBlocking == false) here:
	 *
	 * As QIOManager will never disable the socket notifiers that are not
	 * to be carried out reentrant, these will (maybe) fire again and again,
	 * so that CPU is wasted.
	 */
	if(qioLevel == 1 || ioWatch->reentrant())
		ioWatch->client()->notifyIO(ioWatch->fd(),ioWatch->type());
	
	if(qioLevel == 1)
		Dispatcher::unlock();
	qioLevel--;
}

void QIOManager::dispatch(QTimeWatch *timeWatch)
{
	qioLevel++;
	if(qioLevel == 1)
		Dispatcher::lock();

	// timers are never done reentrant
	if(qioLevel == 1)
		timeWatch->client()->notifyTime();
	
	if(qioLevel == 1)
		Dispatcher::unlock();
	qioLevel--;
}

bool QIOManager::blocking()
{
	return qioBlocking;
}

void QIOManager::setBlocking(bool blocking)
{
	qioBlocking = blocking;
}

#include "qiomanager_p.moc"