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41
42 #include "qplatformdefs.h"
43 #include "qapplication.h"
44 #include "qeventdispatcher_qpa_p.h"
45 #include "private/qeventdispatcher_unix_p.h"
46 #include "qapplication_p.h"
47 #include "qplatformeventloopintegration_qpa.h"
48
49 #include <QWindowSystemInterface>
50 #include <QtCore/QElapsedTimer>
51 #include <QtCore/QAtomicInt>
52 #include <QtCore/QSemaphore>
53
54 #include <QtCore/QDebug>
55
56 #include <errno.h>
57 #include <limits.h>
58
59 QT_BEGIN_NAMESPACE
60
61 QT_USE_NAMESPACE
62
63 class Rendezvous
64 {
65 public:
checkpoint()66 void checkpoint()
67 {
68 if (state.testAndSetOrdered(0,1)) {
69 semaphore.acquire();
70 } else if (state.testAndSetAcquire(1,0)) {
71 semaphore.release();
72 } else {
73 qWarning("Barrier internal error");
74 }
75 }
76 private:
77 QSemaphore semaphore;
78 QAtomicInt state;
79 };
80
81 class SelectWorker : public QThread
82 {
83 public:
SelectWorker(QEventDispatcherQPAPrivate * eventDispatcherPrivate)84 SelectWorker(QEventDispatcherQPAPrivate *eventDispatcherPrivate)
85 : QThread(),
86 m_edPrivate(eventDispatcherPrivate),
87 m_retVal(0)
88 {
89 }
90
setSelectValues(int nfds,fd_set * readfds,fd_set * writefds,fd_set * exceptfds)91 void setSelectValues(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds)
92 {
93 m_nfds = nfds;
94 m_readfds = readfds;
95 m_writefds = writefds;
96 m_exceptfds = exceptfds;
97
98
99 }
100
retVal() const101 int retVal() const {
102 return m_retVal;
103 }
104
105 protected:
106 void run();
107
108 private:
109 QEventDispatcherQPAPrivate *m_edPrivate;
110 int m_retVal;
111
112 int m_nfds;
113 fd_set *m_readfds, *m_writefds, *m_exceptfds;
114 };
115
116 class QEventDispatcherQPAPrivate : public QEventDispatcherUNIXPrivate
117 {
118 Q_DECLARE_PUBLIC(QEventDispatcherQPA)
119 public:
QEventDispatcherQPAPrivate()120 QEventDispatcherQPAPrivate()
121 : eventLoopIntegration(0),
122 barrierBeforeBlocking(0),
123 barrierReturnValue(0),
124 selectReturnMutex(0),
125 selectWorkerNeedsSync(true),
126 selectWorkerHasResult(false),
127 selectWorker(0),
128 m_integrationInitialised(false),
129 m_hasIntegration(false),
130 m_isEventLoopIntegrationRunning(false)
131 {
132
133 }
134
~QEventDispatcherQPAPrivate()135 ~QEventDispatcherQPAPrivate()
136 {
137 delete selectWorker;
138 delete eventLoopIntegration;
139 delete barrierBeforeBlocking;
140 delete barrierReturnValue;
141 delete selectReturnMutex;
142 }
143
hasIntegration() const144 bool hasIntegration() const
145 {
146 if (!m_integrationInitialised) {
147 QEventDispatcherQPAPrivate *that = const_cast<QEventDispatcherQPAPrivate *>(this);
148 if (qApp && (qApp->thread() == QThread::currentThread())) { // guiThread
149 if (QApplicationPrivate::platformIntegration()) {
150 that->eventLoopIntegration = QApplicationPrivate::platformIntegration()->createEventLoopIntegration();
151 if (that->eventLoopIntegration) {
152 that->selectWorker = new SelectWorker(that);
153 that->barrierBeforeBlocking = new Rendezvous;
154 that->barrierReturnValue = new Rendezvous;
155 that->selectReturnMutex = new QMutex;
156 that->selectWorker->start();
157 that->m_hasIntegration = true;
158 if (!QElapsedTimer::isMonotonic())
159 qWarning("Having eventloop integration without monotonic timers can lead to undefined behaviour");
160 }
161 }
162 }
163 that->m_integrationInitialised = true;
164 }
165 return m_hasIntegration;
166 }
167
isEventLoopIntegrationRunning() const168 bool isEventLoopIntegrationRunning() const
169 {
170 return m_isEventLoopIntegrationRunning;
171 }
172
runEventLoopIntegration()173 void runEventLoopIntegration()
174 {
175 if (qApp && (qApp->thread() == QThread::currentThread())) {
176 m_isEventLoopIntegrationRunning = true;
177 eventLoopIntegration->startEventLoop();
178 }
179 }
180
181 QPlatformEventLoopIntegration *eventLoopIntegration;
182 Rendezvous *barrierBeforeBlocking;
183 Rendezvous *barrierReturnValue;
184
185 QMutex *selectReturnMutex;
186 bool selectWorkerNeedsSync;
187 bool selectWorkerHasResult;
188
189 SelectWorker *selectWorker;
190 private:
191 bool m_integrationInitialised;
192 bool m_hasIntegration;
193 bool m_isEventLoopIntegrationRunning;
194 };
195
QEventDispatcherQPA(QObject * parent)196 QEventDispatcherQPA::QEventDispatcherQPA(QObject *parent)
197 : QEventDispatcherUNIX(*new QEventDispatcherQPAPrivate, parent)
198 { }
199
~QEventDispatcherQPA()200 QEventDispatcherQPA::~QEventDispatcherQPA()
201 { }
202
processEvents(QEventLoop::ProcessEventsFlags flags)203 bool QEventDispatcherQPA::processEvents(QEventLoop::ProcessEventsFlags flags)
204 {
205 Q_D(QEventDispatcherQPA);
206
207 if (d->hasIntegration()) {
208 if (!d->isEventLoopIntegrationRunning()) {
209 d->runEventLoopIntegration();
210 }
211 if (d->threadData->quitNow) {
212 d->eventLoopIntegration->quitEventLoop();
213 return false;
214 }
215 }
216
217 int nevents = 0;
218
219 // handle gui and posted events
220 d->interrupt = false;
221 QApplication::sendPostedEvents();
222
223 while (!d->interrupt) { // also flushes output buffer ###can be optimized
224 QWindowSystemInterfacePrivate::WindowSystemEvent *event;
225 if (!(flags & QEventLoop::ExcludeUserInputEvents)
226 && QWindowSystemInterfacePrivate::windowSystemEventsQueued() > 0) {
227 // process a pending user input event
228 event = QWindowSystemInterfacePrivate::getWindowSystemEvent();
229 if (!event)
230 break;
231 } else {
232 break;
233 }
234
235 if (filterEvent(event)) {
236 delete event;
237 continue;
238 }
239 nevents++;
240
241 QApplicationPrivate::processWindowSystemEvent(event);
242 delete event;
243 }
244
245 if (!d->interrupt) {
246 if (QEventDispatcherUNIX::processEvents(flags))
247 return true;
248 }
249
250 return (nevents > 0);
251 }
252
hasPendingEvents()253 bool QEventDispatcherQPA::hasPendingEvents()
254 {
255 extern uint qGlobalPostedEventsCount(); // from qapplication.cpp
256 return qGlobalPostedEventsCount() || QWindowSystemInterfacePrivate::windowSystemEventsQueued();
257 }
258
registerSocketNotifier(QSocketNotifier * notifier)259 void QEventDispatcherQPA::registerSocketNotifier(QSocketNotifier *notifier)
260 {
261 Q_D(QEventDispatcherQPA);
262 QEventDispatcherUNIX::registerSocketNotifier(notifier);
263 if (d->hasIntegration())
264 wakeUp();
265
266 }
267
unregisterSocketNotifier(QSocketNotifier * notifier)268 void QEventDispatcherQPA::unregisterSocketNotifier(QSocketNotifier *notifier)
269 {
270 Q_D(QEventDispatcherQPA);
271 QEventDispatcherUNIX::unregisterSocketNotifier(notifier);
272 if (d->hasIntegration())
273 wakeUp();
274 }
275
flush()276 void QEventDispatcherQPA::flush()
277 {
278 if(qApp)
279 qApp->sendPostedEvents();
280 }
281
select(int nfds,fd_set * readfds,fd_set * writefds,fd_set * exceptfds,timeval * timeout)282 int QEventDispatcherQPA::select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
283 timeval *timeout)
284 {
285 Q_D(QEventDispatcherQPA);
286 int retVal = 0;
287 if (d->hasIntegration()) {
288 qint64 timeoutmsec = LONG_MAX; // wait if we don't have timers
289 if (timeout)
290 timeoutmsec = timeout->tv_sec * 1000 + (timeout->tv_usec/1000);
291 d->selectReturnMutex->lock();
292 if (d->selectWorkerNeedsSync) {
293 if (d->selectWorkerHasResult) {
294 retVal = d->selectWorker->retVal();
295 d->selectWorkerHasResult = false;
296
297 d->selectReturnMutex->unlock();
298 d->barrierReturnValue->checkpoint();
299 d->eventLoopIntegration->setNextTimerEvent(0);
300 return retVal;
301 } else {
302 d->selectWorkerNeedsSync = false;
303 d->selectWorker->setSelectValues(nfds,readfds, writefds, exceptfds);
304 d->barrierBeforeBlocking->checkpoint();
305 }
306 }
307 d->selectReturnMutex->unlock();
308 d->eventLoopIntegration->setNextTimerEvent(timeoutmsec);
309 retVal = 0; //is 0 if select has not returned
310 } else {
311 retVal = QEventDispatcherUNIX::select(nfds, readfds, writefds, exceptfds, timeout);
312 }
313 return retVal;
314 }
315
316
run()317 void SelectWorker::run()
318 {
319
320 while(true) {
321 m_retVal = 0;
322 m_edPrivate->barrierBeforeBlocking->checkpoint(); // wait for mainthread
323 int tmpRet = qt_safe_select(m_nfds,m_readfds,m_writefds,m_exceptfds,0);
324 m_edPrivate->selectReturnMutex->lock();
325 m_edPrivate->eventLoopIntegration->qtNeedsToProcessEvents();
326
327 m_edPrivate->selectWorkerNeedsSync = true;
328 m_edPrivate->selectWorkerHasResult = true;
329 m_retVal = tmpRet;
330
331 m_edPrivate->selectReturnMutex->unlock();
332 m_edPrivate->barrierReturnValue->checkpoint();
333 }
334 }
335 QT_END_NAMESPACE
336