qreadwritelock.cpp

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4 ** Contact: http://www.qt.io/licensing/ -

5 ** -

6 ** This file is part of the QtCore module of the Qt Toolkit. -

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32 ****************************************************************************/ -

33 -

34 #include "qplatformdefs.h" -

35 #include "qreadwritelock.h" -

36 -

37 #ifndef QT_NO_THREAD -

38 #include "qmutex.h" -

39 #include "qthread.h" -

40 #include "qwaitcondition.h" -

41 -

42 #include "qreadwritelock_p.h" -

43 -

44 QT_BEGIN_NAMESPACE -

45 -

46 /*! \class QReadWriteLock -

47 \inmodule QtCore -

48 \brief The QReadWriteLock class provides read-write locking. -

49 -

50 \threadsafe -

51 -

52 \ingroup thread -

53 -

54 A read-write lock is a synchronization tool for protecting -

55 resources that can be accessed for reading and writing. This type -

56 of lock is useful if you want to allow multiple threads to have -

57 simultaneous read-only access, but as soon as one thread wants to -

58 write to the resource, all other threads must be blocked until -

59 the writing is complete. -

60 -

61 In many cases, QReadWriteLock is a direct competitor to QMutex. -

62 QReadWriteLock is a good choice if there are many concurrent -

63 reads and writing occurs infrequently. -

64 -

65 Example: -

66 -

67 \snippet code/src_corelib_thread_qreadwritelock.cpp 0 -

68 -

69 To ensure that writers aren't blocked forever by readers, readers -

70 attempting to obtain a lock will not succeed if there is a blocked -

71 writer waiting for access, even if the lock is currently only -

72 accessed by other readers. Also, if the lock is accessed by a -

73 writer and another writer comes in, that writer will have -

74 priority over any readers that might also be waiting. -

75 -

76 Like QMutex, a QReadWriteLock can be recursively locked by the -

77 same thread when constructed with \l{QReadWriteLock::Recursive} as -

78 \l{QReadWriteLock::RecursionMode}. In such cases, -

79 unlock() must be called the same number of times lockForWrite() or -

80 lockForRead() was called. Note that the lock type cannot be -

81 changed when trying to lock recursively, i.e. it is not possible -

82 to lock for reading in a thread that already has locked for -

83 writing (and vice versa). -

84 -

85 \sa QReadLocker, QWriteLocker, QMutex, QSemaphore -

86 */ -

87 -

88 /*! -

89 \enum QReadWriteLock::RecursionMode -

90 \since 4.4 -

91 -

92 \value Recursive In this mode, a thread can lock the same -

93 QReadWriteLock multiple times. The QReadWriteLock won't be unlocked -

94 until a corresponding number of unlock() calls have been made. -

95 -

96 \value NonRecursive In this mode, a thread may only lock a -

97 QReadWriteLock once. -

98 -

99 \sa QReadWriteLock() -

100 */ -

101 -

102 /*! -

103 \since 4.4 -

104 -

105 Constructs a QReadWriteLock object in the given \a recursionMode. -

106 -

107 The default recursion mode is NonRecursive. -

108 -

109 \sa lockForRead(), lockForWrite(), RecursionMode -

110 */ -

111 QReadWriteLock::QReadWriteLock(RecursionMode recursionMode) -

112 : d(new QReadWriteLockPrivate(recursionMode)) -

113

{

executed 39003 times by 297 tests: end of block

Executed by:

tst_Gestures
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
tst_QCalendarWidget
...

}

executed 39003 times by 297 tests: end of block

Executed by:

tst_Gestures
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
tst_QCalendarWidget
...

39003

114 -

115 /*! -

116 Destroys the QReadWriteLock object. -

117 -

118 \warning Destroying a read-write lock that is in use may result -

119 in undefined behavior. -

120 */ -

121 QReadWriteLock::~QReadWriteLock() -

122 { -

123 delete d; -

124

}

executed 39976 times by 552 tests: end of block

Executed by:

tst_QDBusAbstractInterface
tst_QDBusConnection
tst_QDBusConnection_NoApplication
tst_QDBusConnection_SpyHook
tst_QDBusServiceWatcher
tst_QDBusThreading
tst_QGlobalStatic
tst_QReadLocker
tst_QReadWriteLock
tst_QWaitCondition
tst_QWriteLocker
tst_collections - unknown status
tst_compiler - unknown status
tst_gestures - unknown status
tst_lancelot - unknown status
tst_languagechange - unknown status
tst_largefile - unknown status
tst_modeltest - unknown status
tst_networkselftest - unknown status
tst_platformsocketengine - unknown status
tst_q_func_info - unknown status
tst_qabstractanimation - unknown status
tst_qabstractbutton - unknown status
tst_qabstractfileengine - unknown status
tst_qabstractitemmodel - unknown status
...

39976

125 -

126 /*! -

127 Locks the lock for reading. This function will block the current -

128 thread if another thread has locked for writing. -

129 -

130 It is not possible to lock for read if the thread already has -

131 locked for write. -

132 -

133 \sa unlock(), lockForWrite(), tryLockForRead() -

134 */ -

135 void QReadWriteLock::lockForRead() -

136 { -

137 QMutexLocker lock(&d->mutex); -

138 -

139 Qt::HANDLE self = 0; -

140

if (d->recursive) {

d->recursive

Description

TRUE

evaluated 90 times by 5 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1685730 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

90-1685730

141 self = QThread::currentThreadId(); -

142 -

143 QHash<Qt::HANDLE, int>::iterator it = d->currentReaders.find(self); -

144

if (it != d->currentReaders.end()) {

it != d->currentReaders.end()	Description
TRUE	evaluated 8 times by 2 tests Evaluated by: tst_QAbstractFileEngine tst_QFile
FALSE	evaluated 82 times by 5 tests Evaluated by: tst_QAbstractFileEngine tst_QDirIterator tst_QFile tst_QReadWriteLock tst_QWaitCondition

8-82

145 ++it.value(); -

146 ++d->accessCount; -

147 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::lockForRead()", -

148 "Overflow in lock counter"); -

149

return;

executed 8 times by 2 tests: return;

Executed by:

tst_QAbstractFileEngine
tst_QFile

150 } -

151

}

executed 82 times by 5 tests: end of block

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

152 -

153

while (d->accessCount < 0 || d->waitingWriters) {

d->accessCount < 0

Description

TRUE

evaluated 61 times by 3 tests

Evaluated by:

tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1686319 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

d->waitingWriters

Description

TRUE

evaluated 507 times by 2 tests

Evaluated by:

tst_QMetaType
tst_QReadWriteLock

FALSE

evaluated 1685812 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

61-1686319

154 ++d->waitingReaders; -

155 d->readerWait.wait(&d->mutex); -

156 --d->waitingReaders; -

157

}

executed 568 times by 3 tests: end of block

Executed by:

tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

568

158

if (d->recursive)

d->recursive

Description

TRUE

evaluated 82 times by 5 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1685730 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

82-1685730

159

d->currentReaders.insert(self, 1);

executed 82 times by 5 tests: d->currentReaders.insert(self, 1);

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

160 -

161 ++d->accessCount; -

162 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::lockForRead()", "Overflow in lock counter"); -

163

}

executed 1685812 times by 357 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

1685812

164 -

165 /*! -

166 Attempts to lock for reading. If the lock was obtained, this -

167 function returns \c true, otherwise it returns \c false instead of -

168 waiting for the lock to become available, i.e. it does not block. -

169 -

170 The lock attempt will fail if another thread has locked for -

171 writing. -

172 -

173 If the lock was obtained, the lock must be unlocked with unlock() -

174 before another thread can successfully lock it for writing. -

175 -

176 It is not possible to lock for read if the thread already has -

177 locked for write. -

178 -

179 \sa unlock(), lockForRead() -

180 */ -

181 bool QReadWriteLock::tryLockForRead() -

182 { -

183 QMutexLocker lock(&d->mutex); -

184 -

185 Qt::HANDLE self = 0; -

186

if (d->recursive) {

d->recursive	Description
TRUE	evaluated 36 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 7 times by 1 test Evaluated by: tst_QReadWriteLock

7-36

187 self = QThread::currentThreadId(); -

188 -

189 QHash<Qt::HANDLE, int>::iterator it = d->currentReaders.find(self); -

190

if (it != d->currentReaders.end()) {

it != d->currentReaders.end()	Description
TRUE	evaluated 11 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 25 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition

11-25

191 ++it.value(); -

192 ++d->accessCount; -

193 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::tryLockForRead()", -

194 "Overflow in lock counter"); -

195

return true;

executed 11 times by 2 tests: return true;

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

196 } -

197

}

executed 25 times by 2 tests: end of block

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

198 -

199

if (d->accessCount < 0)

d->accessCount < 0	Description
TRUE	evaluated 23 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 9 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition

9-23

200

return false;

executed 23 times by 2 tests: return false;

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

201

if (d->recursive)

d->recursive	Description
TRUE	evaluated 4 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 5 times by 1 test Evaluated by: tst_QReadWriteLock

4-5

202

d->currentReaders.insert(self, 1);

executed 4 times by 2 tests: d->currentReaders.insert(self, 1);

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

203 -

204 ++d->accessCount; -

205 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::tryLockForRead()", "Overflow in lock counter"); -

206 -

207

return true;

executed 9 times by 2 tests: return true;

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

208 } -

209 -

210 /*! \overload -

211 -

212 Attempts to lock for reading. This function returns \c true if the -

213 lock was obtained; otherwise it returns \c false. If another thread -

214 has locked for writing, this function will wait for at most \a -

215 timeout milliseconds for the lock to become available. -

216 -

217 Note: Passing a negative number as the \a timeout is equivalent to -

218 calling lockForRead(), i.e. this function will wait forever until -

219 lock can be locked for reading when \a timeout is negative. -

220 -

221 If the lock was obtained, the lock must be unlocked with unlock() -

222 before another thread can successfully lock it for writing. -

223 -

224 It is not possible to lock for read if the thread already has -

225 locked for write. -

226 -

227 \sa unlock(), lockForRead() -

228 */ -

229 bool QReadWriteLock::tryLockForRead(int timeout) -

230 { -

231 QMutexLocker lock(&d->mutex); -

232 -

233 Qt::HANDLE self = 0; -

234

if (d->recursive) {

d->recursive	Description
TRUE	never evaluated
FALSE	evaluated 3 times by 1 test Evaluated by: tst_QReadWriteLock

0-3

235 self = QThread::currentThreadId(); -

236 -

237 QHash<Qt::HANDLE, int>::iterator it = d->currentReaders.find(self); -

238

if (it != d->currentReaders.end()) {

it != d->currentReaders.end()	Description
TRUE	never evaluated
FALSE	never evaluated

239 ++it.value(); -

240 ++d->accessCount; -

241 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::tryLockForRead()", -

242 "Overflow in lock counter"); -

243

return true;

never executed: return true;

244 } -

245

}

never executed: end of block

246 -

247

while (d->accessCount < 0 || d->waitingWriters) {

d->accessCount < 0	Description
TRUE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock
FALSE	evaluated 2 times by 1 test Evaluated by: tst_QReadWriteLock

d->waitingWriters	Description
TRUE	never evaluated
FALSE	evaluated 2 times by 1 test Evaluated by: tst_QReadWriteLock

0-2

248 ++d->waitingReaders; -

249 bool success = d->readerWait.wait(&d->mutex, timeout < 0 ? ULONG_MAX : ulong(timeout)); -

250 --d->waitingReaders; -

251

if (!success)

!success	Description
TRUE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock
FALSE	never evaluated

0-1

252

return false;

executed 1 time by 1 test: return false;

Executed by:

tst_QReadWriteLock

253

}

never executed: end of block

254

if (d->recursive)

d->recursive	Description
TRUE	never evaluated
FALSE	evaluated 2 times by 1 test Evaluated by: tst_QReadWriteLock

0-2

255

d->currentReaders.insert(self, 1);

never executed: d->currentReaders.insert(self, 1);

256 -

257 ++d->accessCount; -

258 Q_ASSERT_X(d->accessCount > 0, "QReadWriteLock::tryLockForRead()", "Overflow in lock counter"); -

259 -

260

return true;

executed 2 times by 1 test: return true;

Executed by:

tst_QReadWriteLock

261 } -

262 -

263 /*! -

264 Locks the lock for writing. This function will block the current -

265 thread if another thread (including the current) has locked for -

266 reading or writing (unless the lock has been created using the -

267 \l{QReadWriteLock::Recursive} mode). -

268 -

269 It is not possible to lock for write if the thread already has -

270 locked for read. -

271 -

272 \sa unlock(), lockForRead(), tryLockForWrite() -

273 */ -

274 void QReadWriteLock::lockForWrite() -

275 { -

276 QMutexLocker lock(&d->mutex); -

277 -

278 Qt::HANDLE self = 0; -

279

if (d->recursive) {

d->recursive

Description

TRUE

evaluated 37 times by 8 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition
tst_qabstractfileengine - unknown status
tst_qdiriterator - unknown status
tst_qfile - unknown status

FALSE

evaluated 330454 times by 559 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

37-330454

280 self = QThread::currentThreadId(); -

281 -

282

if (d->currentWriter == self) {

d->currentWriter == self	Description
TRUE	never evaluated
FALSE	evaluated 37 times by 8 tests Evaluated by: tst_QAbstractFileEngine tst_QDirIterator tst_QFile tst_QReadWriteLock tst_QWaitCondition tst_qabstractfileengine - unknown status tst_qdiriterator - unknown status tst_qfile - unknown status

0-37

283 --d->accessCount; -

284 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::lockForWrite()", -

285 "Overflow in lock counter"); -

286

return;

never executed: return;

287 } -

288

}

executed 37 times by 8 tests: end of block

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition
tst_qabstractfileengine - unknown status
tst_qdiriterator - unknown status
tst_qfile - unknown status

289 -

290

while (d->accessCount != 0) {

d->accessCount != 0

Description

TRUE

evaluated 261 times by 5 tests

Evaluated by:

tst_QDBusConnection
tst_QDBusThreading
tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 330491 times by 563 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

261-330491

291 ++d->waitingWriters; -

292 d->writerWait.wait(&d->mutex); -

293 --d->waitingWriters; -

294

}

executed 261 times by 5 tests: end of block

Executed by:

tst_QDBusConnection
tst_QDBusThreading
tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

261

295

if (d->recursive)

d->recursive

Description

TRUE

evaluated 37 times by 8 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition
tst_qabstractfileengine - unknown status
tst_qdiriterator - unknown status
tst_qfile - unknown status

FALSE

evaluated 330454 times by 559 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

37-330454

296

d->currentWriter = self;

executed 37 times by 8 tests: d->currentWriter = self;

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition
tst_qabstractfileengine - unknown status
tst_qdiriterator - unknown status
tst_qfile - unknown status

297 -

298 --d->accessCount; -

299 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::lockForWrite()", "Overflow in lock counter"); -

300

}

executed 330491 times by 563 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

330491

301 -

302 /*! -

303 Attempts to lock for writing. If the lock was obtained, this -

304 function returns \c true; otherwise, it returns \c false immediately. -

305 -

306 The lock attempt will fail if another thread has locked for -

307 reading or writing. -

308 -

309 If the lock was obtained, the lock must be unlocked with unlock() -

310 before another thread can successfully lock it. -

311 -

312 It is not possible to lock for write if the thread already has -

313 locked for read. -

314 -

315 \sa unlock(), lockForWrite() -

316 */ -

317 bool QReadWriteLock::tryLockForWrite() -

318 { -

319 QMutexLocker lock(&d->mutex); -

320 -

321 Qt::HANDLE self = 0; -

322

if (d->recursive) {

d->recursive	Description
TRUE	evaluated 39 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 23 times by 3 tests Evaluated by: tst_QReadLocker tst_QReadWriteLock tst_QWriteLocker

23-39

323 self = QThread::currentThreadId(); -

324 -

325

if (d->currentWriter == self) {

d->currentWriter == self	Description
TRUE	evaluated 12 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 27 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition

12-27

326 --d->accessCount; -

327 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::lockForWrite()", -

328 "Overflow in lock counter"); -

329

return true;

executed 12 times by 2 tests: return true;

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

330 } -

331

}

executed 27 times by 2 tests: end of block

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

332 -

333

if (d->accessCount != 0)

d->accessCount != 0	Description
TRUE	evaluated 32 times by 4 tests Evaluated by: tst_QReadLocker tst_QReadWriteLock tst_QWaitCondition tst_QWriteLocker
FALSE	evaluated 18 times by 4 tests Evaluated by: tst_QReadLocker tst_QReadWriteLock tst_QWaitCondition tst_QWriteLocker

18-32

334

return false;

executed 32 times by 4 tests: return false;

Executed by:

tst_QReadLocker
tst_QReadWriteLock
tst_QWaitCondition
tst_QWriteLocker

335

if (d->recursive)

d->recursive	Description
TRUE	evaluated 5 times by 2 tests Evaluated by: tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 13 times by 3 tests Evaluated by: tst_QReadLocker tst_QReadWriteLock tst_QWriteLocker

5-13

336

d->currentWriter = self;

executed 5 times by 2 tests: d->currentWriter = self;

Executed by:

tst_QReadWriteLock
tst_QWaitCondition

337 -

338 --d->accessCount; -

339 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::tryLockForWrite()", -

340 "Overflow in lock counter"); -

341 -

342

return true;

executed 18 times by 4 tests: return true;

Executed by:

tst_QReadLocker
tst_QReadWriteLock
tst_QWaitCondition
tst_QWriteLocker

343 } -

344 -

345 /*! \overload -

346 -

347 Attempts to lock for writing. This function returns \c true if the -

348 lock was obtained; otherwise it returns \c false. If another thread -

349 has locked for reading or writing, this function will wait for at -

350 most \a timeout milliseconds for the lock to become available. -

351 -

352 Note: Passing a negative number as the \a timeout is equivalent to -

353 calling lockForWrite(), i.e. this function will wait forever until -

354 lock can be locked for writing when \a timeout is negative. -

355 -

356 If the lock was obtained, the lock must be unlocked with unlock() -

357 before another thread can successfully lock it. -

358 -

359 It is not possible to lock for write if the thread already has -

360 locked for read. -

361 -

362 \sa unlock(), lockForWrite() -

363 */ -

364 bool QReadWriteLock::tryLockForWrite(int timeout) -

365 { -

366 QMutexLocker lock(&d->mutex); -

367 -

368 Qt::HANDLE self = 0; -

369

if (d->recursive) {

d->recursive	Description
TRUE	never evaluated
FALSE	evaluated 2 times by 1 test Evaluated by: tst_QReadWriteLock

0-2

370 self = QThread::currentThreadId(); -

371 -

372

if (d->currentWriter == self) {

d->currentWriter == self	Description
TRUE	never evaluated
FALSE	never evaluated

373 --d->accessCount; -

374 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::lockForWrite()", -

375 "Overflow in lock counter"); -

376

return true;

never executed: return true;

377 } -

378

}

never executed: end of block

379 -

380

while (d->accessCount != 0) {

d->accessCount != 0	Description
TRUE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock
FALSE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock

381 ++d->waitingWriters; -

382 bool success = d->writerWait.wait(&d->mutex, timeout < 0 ? ULONG_MAX : ulong(timeout)); -

383 --d->waitingWriters; -

384 -

385

if (!success)

!success	Description
TRUE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock
FALSE	never evaluated

0-1

386

return false;

executed 1 time by 1 test: return false;

Executed by:

tst_QReadWriteLock

387

}

never executed: end of block

388

if (d->recursive)

d->recursive	Description
TRUE	never evaluated
FALSE	evaluated 1 time by 1 test Evaluated by: tst_QReadWriteLock

0-1

389

d->currentWriter = self;

never executed: d->currentWriter = self;

390 -

391 --d->accessCount; -

392 Q_ASSERT_X(d->accessCount < 0, "QReadWriteLock::tryLockForWrite()", -

393 "Overflow in lock counter"); -

394 -

395

return true;

executed 1 time by 1 test: return true;

Executed by:

tst_QReadWriteLock

396 } -

397 -

398 /*! -

399 Unlocks the lock. -

400 -

401 Attempting to unlock a lock that is not locked is an error, and will result -

402 in program termination. -

403 -

404 \sa lockForRead(), lockForWrite(), tryLockForRead(), tryLockForWrite() -

405 */ -

406 void QReadWriteLock::unlock() -

407 { -

408 QMutexLocker lock(&d->mutex); -

409 -

410 Q_ASSERT_X(d->accessCount != 0, "QReadWriteLock::unlock()", "Cannot unlock an unlocked lock"); -

411 -

412 bool unlocked = false; -

413

if (d->accessCount > 0) {

d->accessCount > 0

Description

TRUE

evaluated 1685842 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

FALSE

evaluated 330522 times by 564 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

330522-1685842

414 // releasing a read lock -

415

if (d->recursive) {

d->recursive

Description

TRUE

evaluated 105 times by 5 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1685737 times by 357 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

105-1685737

416 Qt::HANDLE self = QThread::currentThreadId(); -

417 QHash<Qt::HANDLE, int>::iterator it = d->currentReaders.find(self); -

418

if (it != d->currentReaders.end()) {

it != d->currentReaders.end()	Description
TRUE	evaluated 105 times by 5 tests Evaluated by: tst_QAbstractFileEngine tst_QDirIterator tst_QFile tst_QReadWriteLock tst_QWaitCondition
FALSE	never evaluated

0-105

419

if (--it.value() <= 0)

--it.value() <= 0	Description
TRUE	evaluated 86 times by 5 tests Evaluated by: tst_QAbstractFileEngine tst_QDirIterator tst_QFile tst_QReadWriteLock tst_QWaitCondition
FALSE	evaluated 19 times by 4 tests Evaluated by: tst_QAbstractFileEngine tst_QFile tst_QReadWriteLock tst_QWaitCondition

19-86

420

d->currentReaders.erase(it);

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

421

}

executed 105 times by 5 tests: end of block

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

105

422

}

executed 105 times by 5 tests: end of block

Executed by:

tst_QAbstractFileEngine
tst_QDirIterator
tst_QFile
tst_QReadWriteLock
tst_QWaitCondition

105

423 -

424 unlocked = --d->accessCount == 0; -

425

} else if (d->accessCount < 0 && ++d->accessCount == 0) {

executed 1685842 times by 357 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
tst_QButtonGroup
...

d->accessCount < 0

Description

TRUE

evaluated 330522 times by 564 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

FALSE

never evaluated

++d->accessCount == 0

Description

TRUE

evaluated 330510 times by 564 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

FALSE

evaluated 12 times by 2 tests

Evaluated by:

tst_QReadWriteLock
tst_QWaitCondition

0-1685842

426 // released a write lock -

427 unlocked = true; -

428 d->currentWriter = 0; -

429

}

executed 330510 times by 564 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

330510

430 -

431

if (unlocked) {

unlocked

Description

TRUE

evaluated 1872432 times by 570 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

FALSE

evaluated 143932 times by 10 tests

Evaluated by:

tst_QAbstractFileEngine
tst_QDBusConnection
tst_QDBusThreading
tst_QFile
tst_QHttpNetworkConnection
tst_QMetaType
tst_QNetworkReply
tst_QReadWriteLock
tst_QWaitCondition
tst_Spdy

143932-1872432

432

if (d->waitingWriters) {

d->waitingWriters

Description

TRUE

evaluated 6953 times by 5 tests

Evaluated by:

tst_QDBusConnection
tst_QDBusThreading
tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1865479 times by 570 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

6953-1865479

433 d->writerWait.wakeOne(); -

434

} else if (d->waitingReaders) {

executed 6953 times by 5 tests: end of block

Executed by:

tst_QDBusConnection
tst_QDBusThreading
tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

d->waitingReaders

Description

TRUE

evaluated 217 times by 3 tests

Evaluated by:

tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

FALSE

evaluated 1865262 times by 570 tests

Evaluated by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

217-1865262

435 d->readerWait.wakeAll(); -

436

}

executed 217 times by 3 tests: end of block

Executed by:

tst_QMetaType
tst_QReadWriteLock
tst_QWaitCondition

217

437

}

executed 1872432 times by 570 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

1872432

438

}

executed 2016364 times by 570 tests: end of block

Executed by:

tst_Gestures
tst_Lancelot
tst_ModelTest
tst_NetworkSelfTest
tst_QAbstractButton
tst_QAbstractFileEngine
tst_QAbstractItemModel
tst_QAbstractItemView
tst_QAbstractNetworkCache
tst_QAbstractProxyModel
tst_QAbstractScrollArea
tst_QAbstractSlider
tst_QAbstractSpinBox
tst_QAbstractTextDocumentLayout
tst_QAccessibility
tst_QAction
tst_QActionGroup
tst_QAlgorithms
tst_QAnimationGroup
tst_QApplication
tst_QArrayData
tst_QArrayData_StrictIterators
tst_QAsn1Element
tst_QBackingStore
tst_QBoxLayout
...

2016364

439 -

440 /*! -

441 \class QReadLocker -

442 \inmodule QtCore -

443 \brief The QReadLocker class is a convenience class that -

444 simplifies locking and unlocking read-write locks for read access. -

445 -

446 \threadsafe -

447 -

448 \ingroup thread -

449 -

450 The purpose of QReadLocker (and QWriteLocker) is to simplify -

451 QReadWriteLock locking and unlocking. Locking and unlocking -

452 statements or in exception handling code is error-prone and -

453 difficult to debug. QReadLocker can be used in such situations -

454 to ensure that the state of the lock is always well-defined. -

455 -

456 Here's an example that uses QReadLocker to lock and unlock a -

457 read-write lock for reading: -

458 -

459 \snippet code/src_corelib_thread_qreadwritelock.cpp 1 -

460 -

461 It is equivalent to the following code: -

462 -

463 \snippet code/src_corelib_thread_qreadwritelock.cpp 2 -

464 -

465 The QMutexLocker documentation shows examples where the use of a -

466 locker object greatly simplifies programming. -

467 -

468 \sa QWriteLocker, QReadWriteLock -

469 */ -

470 -

471 /*! -

472 \fn QReadLocker::QReadLocker(QReadWriteLock *lock) -

473 -

474 Constructs a QReadLocker and locks \a lock for reading. The lock -

475 will be unlocked when the QReadLocker is destroyed. If \c lock is -

476 zero, QReadLocker does nothing. -

477 -

478 \sa QReadWriteLock::lockForRead() -

479 */ -

480 -

481 /*! -

482 \fn QReadLocker::~QReadLocker() -

483 -

484 Destroys the QReadLocker and unlocks the lock that was passed to -

485 the constructor. -

486 -

487 \sa QReadWriteLock::unlock() -

488 */ -

489 -

490 /*! -

491 \fn void QReadLocker::unlock() -

492 -

493 Unlocks the lock associated with this locker. -

494 -

495 \sa QReadWriteLock::unlock() -

496 */ -

497 -

498 /*! -

499 \fn void QReadLocker::relock() -

500 -

501 Relocks an unlocked lock. -

502 -

503 \sa unlock() -

504 */ -

505 -

506 /*! -

507 \fn QReadWriteLock *QReadLocker::readWriteLock() const -

508 -

509 Returns a pointer to the read-write lock that was passed -

510 to the constructor. -

511 */ -

512 -

513 /*! -

514 \class QWriteLocker -

515 \inmodule QtCore -

516 \brief The QWriteLocker class is a convenience class that -

517 simplifies locking and unlocking read-write locks for write access. -

518 -

519 \threadsafe -

520 -

521 \ingroup thread -

522 -

523 The purpose of QWriteLocker (and QReadLocker) is to simplify -

524 QReadWriteLock locking and unlocking. Locking and unlocking -

525 statements or in exception handling code is error-prone and -

526 difficult to debug. QWriteLocker can be used in such situations -

527 to ensure that the state of the lock is always well-defined. -

528 -

529 Here's an example that uses QWriteLocker to lock and unlock a -

530 read-write lock for writing: -

531 -

532 \snippet code/src_corelib_thread_qreadwritelock.cpp 3 -

533 -

534 It is equivalent to the following code: -

535 -

536 \snippet code/src_corelib_thread_qreadwritelock.cpp 4 -

537 -

538 The QMutexLocker documentation shows examples where the use of a -

539 locker object greatly simplifies programming. -

540 -

541 \sa QReadLocker, QReadWriteLock -

542 */ -

543 -

544 /*! -

545 \fn QWriteLocker::QWriteLocker(QReadWriteLock *lock) -

546 -

547 Constructs a QWriteLocker and locks \a lock for writing. The lock -

548 will be unlocked when the QWriteLocker is destroyed. If \c lock is -

549 zero, QWriteLocker does nothing. -

550 -

551 \sa QReadWriteLock::lockForWrite() -

552 */ -

553 -

554 /*! -

555 \fn QWriteLocker::~QWriteLocker() -

556 -

557 Destroys the QWriteLocker and unlocks the lock that was passed to -

558 the constructor. -

559 -

560 \sa QReadWriteLock::unlock() -

561 */ -

562 -

563 /*! -

564 \fn void QWriteLocker::unlock() -

565 -

566 Unlocks the lock associated with this locker. -

567 -

568 \sa QReadWriteLock::unlock() -

569 */ -

570 -

571 /*! -

572 \fn void QWriteLocker::relock() -

573 -

574 Relocks an unlocked lock. -

575 -

576 \sa unlock() -

577 */ -

578 -

579 /*! -

580 \fn QReadWriteLock *QWriteLocker::readWriteLock() const -

581 -

582 Returns a pointer to the read-write lock that was passed -

583 to the constructor. -

584 */ -

585 -

586 QT_END_NAMESPACE -

587 -

588 #endif // QT_NO_THREAD -

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