qsharedmemory.cpp

Absolute File Name:/home/qt/qt5_coco/qt5/qtbase/src/corelib/kernel/qsharedmemory.cpp
Source codeSwitch to Preprocessed file
LineSourceCount
1/****************************************************************************-
2**-
3** Copyright (C) 2016 The Qt Company Ltd.-
4** Contact: https://www.qt.io/licensing/-
5**-
6** This file is part of the QtCore module of the Qt Toolkit.-
7**-
8** $QT_BEGIN_LICENSE:LGPL$-
9** Commercial License Usage-
10** Licensees holding valid commercial Qt licenses may use this file in-
11** accordance with the commercial license agreement provided with the-
12** Software or, alternatively, in accordance with the terms contained in-
13** a written agreement between you and The Qt Company. For licensing terms-
14** and conditions see https://www.qt.io/terms-conditions. For further-
15** information use the contact form at https://www.qt.io/contact-us.-
16**-
17** GNU Lesser General Public License Usage-
18** Alternatively, this file may be used under the terms of the GNU Lesser-
19** General Public License version 3 as published by the Free Software-
20** Foundation and appearing in the file LICENSE.LGPL3 included in the-
21** packaging of this file. Please review the following information to-
22** ensure the GNU Lesser General Public License version 3 requirements-
23** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.-
24**-
25** GNU General Public License Usage-
26** Alternatively, this file may be used under the terms of the GNU-
27** General Public License version 2.0 or (at your option) the GNU General-
28** Public license version 3 or any later version approved by the KDE Free-
29** Qt Foundation. The licenses are as published by the Free Software-
30** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3-
31** included in the packaging of this file. Please review the following-
32** information to ensure the GNU General Public License requirements will-
33** be met: https://www.gnu.org/licenses/gpl-2.0.html and-
34** https://www.gnu.org/licenses/gpl-3.0.html.-
35**-
36** $QT_END_LICENSE$-
37**-
38****************************************************************************/-
39-
40#include "qsharedmemory.h"-
41#include "qsharedmemory_p.h"-
42#include "qsystemsemaphore.h"-
43#include <qdir.h>-
44#include <qcryptographichash.h>-
45#include <qdebug.h>-
46#ifdef Q_OS_WIN-
47# include <qt_windows.h>-
48#endif-
49-
50QT_BEGIN_NAMESPACE-
51-
52#if !(defined(QT_NO_SHAREDMEMORY) && defined(QT_NO_SYSTEMSEMAPHORE))-
53/*!-
54 \internal-
55-
56 Generate a string from the key which can be any unicode string into-
57 the subset that the win/unix kernel allows.-
58-
59 On Unix this will be a file name-
60 */-
61QString-
62QSharedMemoryPrivate::makePlatformSafeKey(const QString &key,-
63 const QString &prefix)-
64{-
65 if (key.isEmpty())
key.isEmpty()Description
TRUEevaluated 3737 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
FALSEevaluated 7354 times by 4 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_QSystemSemaphore
  • tst_qsharedmemory - unknown status
  • tst_qsystemsemaphore - unknown status
3737-7354
66 return QString();
executed 3737 times by 2 tests: return QString();
Executed by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
3737
67-
68 QString result = prefix;-
69-
70 QString part1 = key;-
71 part1.replace(QRegExp(QLatin1String("[^A-Za-z]")), QString());-
72 result.append(part1);-
73-
74 QByteArray hex = QCryptographicHash::hash(key.toUtf8(), QCryptographicHash::Sha1).toHex();-
75 result.append(QLatin1String(hex));-
76#ifdef Q_OS_WIN-
77 return result;-
78#elif defined(QT_POSIX_IPC)-
79 return QLatin1Char('/') + result;-
80#else-
81 return QDir::tempPath() + QLatin1Char('/') + result;
executed 7354 times by 4 tests: return QDir::tempPath() + QLatin1Char('/') + result;
Executed by:
  • tst_QSharedMemory
  • tst_QSystemSemaphore
  • tst_qsharedmemory - unknown status
  • tst_qsystemsemaphore - unknown status
7354
82#endif-
83}-
84#endif // QT_NO_SHAREDMEMORY && QT_NO_SHAREDMEMORY-
85-
86#ifndef QT_NO_SHAREDMEMORY-
87-
88/*!-
89 \class QSharedMemory-
90 \inmodule QtCore-
91 \since 4.4-
92-
93 \brief The QSharedMemory class provides access to a shared memory segment.-
94-
95 QSharedMemory provides access to a shared memory segment by multiple-
96 threads and processes. It also provides a way for a single thread or-
97 process to lock the memory for exclusive access.-
98-
99 When using this class, be aware of the following platform-
100 differences:-
101-
102 \list-
103-
104 \li Windows: QSharedMemory does not "own" the shared memory segment.-
105 When all threads or processes that have an instance of QSharedMemory-
106 attached to a particular shared memory segment have either destroyed-
107 their instance of QSharedMemory or exited, the Windows kernel-
108 releases the shared memory segment automatically.-
109-
110 \li Unix: QSharedMemory "owns" the shared memory segment. When the-
111 last thread or process that has an instance of QSharedMemory-
112 attached to a particular shared memory segment detaches from the-
113 segment by destroying its instance of QSharedMemory, the Unix kernel-
114 release the shared memory segment. But if that last thread or-
115 process crashes without running the QSharedMemory destructor, the-
116 shared memory segment survives the crash.-
117-
118 \li HP-UX: Only one attach to a shared memory segment is allowed per-
119 process. This means that QSharedMemory should not be used across-
120 multiple threads in the same process in HP-UX.-
121-
122 \endlist-
123-
124 Remember to lock the shared memory with lock() before reading from-
125 or writing to the shared memory, and remember to release the lock-
126 with unlock() after you are done.-
127-
128 QSharedMemory automatically destroys the shared memory segment when-
129 the last instance of QSharedMemory is detached from the segment, and-
130 no references to the segment remain.-
131-
132 \warning QSharedMemory changes the key in a Qt-specific way, unless otherwise-
133 specified. Interoperation with non-Qt applications is achieved by first creating-
134 a default shared memory with QSharedMemory() and then setting a native key with-
135 setNativeKey(). When using native keys, shared memory is not protected against-
136 multiple accesses on it (for example, unable to lock()) and a user-defined mechanism-
137 should be used to achieve such protection.-
138 */-
139-
140/*!-
141 \overload QSharedMemory()-
142-
143 Constructs a shared memory object with the given \a parent. The-
144 shared memory object's key is not set by the constructor, so the-
145 shared memory object does not have an underlying shared memory-
146 segment attached. The key must be set with setKey() or setNativeKey()-
147 before create() or attach() can be used.-
148-
149 \sa setKey()-
150 */-
151QSharedMemory::QSharedMemory(QObject *parent)-
152 : QObject(*new QSharedMemoryPrivate, parent)-
153{-
154}
executed 4 times by 3 tests: end of block
Executed by:
  • tst_QApplication
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
4
155-
156/*!-
157 Constructs a shared memory object with the given \a parent and with-
158 its key set to \a key. Because its key is set, its create() and-
159 attach() functions can be called.-
160-
161 \sa setKey(), create(), attach()-
162 */-
163QSharedMemory::QSharedMemory(const QString &key, QObject *parent)-
164 : QObject(*new QSharedMemoryPrivate, parent)-
165{-
166 setKey(key);-
167}
executed 3608 times by 1 test: end of block
Executed by:
  • tst_QSharedMemory
3608
168-
169/*!-
170 The destructor clears the key, which forces the shared memory object-
171 to \l {detach()} {detach} from its underlying shared memory-
172 segment. If this shared memory object is the last one connected to-
173 the shared memory segment, the detach() operation destroys the-
174 shared memory segment.-
175-
176 \sa detach(), isAttached()-
177 */-
178QSharedMemory::~QSharedMemory()-
179{-
180 setKey(QString());-
181}
executed 3611 times by 2 tests: end of block
Executed by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
3611
182-
183/*!-
184 Sets the platform independent \a key for this shared memory object. If \a key-
185 is the same as the current key, the function returns without doing anything.-
186-
187 You can call key() to retrieve the platform independent key. Internally,-
188 QSharedMemory converts this key into a platform specific key. If you instead-
189 call nativeKey(), you will get the platform specific, converted key.-
190-
191 If the shared memory object is attached to an underlying shared memory-
192 segment, it will \l {detach()} {detach} from it before setting the new key.-
193 This function does not do an attach().-
194-
195 \sa key(), nativeKey(), isAttached()-
196*/-
197void QSharedMemory::setKey(const QString &key)-
198{-
199 Q_D(QSharedMemory);-
200 if (key == d->key && d->makePlatformSafeKey(key) == d->nativeKey)
key == d->keyDescription
TRUEevaluated 129 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
FALSEevaluated 7101 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
d->makePlatfor...= d->nativeKeyDescription
TRUEevaluated 124 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
FALSEevaluated 5 times by 1 test
Evaluated by:
  • tst_QSharedMemory
5-7101
201 return;
executed 124 times by 2 tests: return;
Executed by:
  • tst_QSharedMemory
  • tst_qapplication - unknown status
124
202-
203 if (isAttached())
isAttached()Description
TRUEevaluated 3465 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3641 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
3465-3641
204 detach();
executed 3465 times by 1 test: detach();
Executed by:
  • tst_QSharedMemory
3465
205 d->cleanHandle();-
206 d->key = key;-
207 d->nativeKey = d->makePlatformSafeKey(key);-
208}
executed 7106 times by 2 tests: end of block
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
7106
209-
210/*!-
211 \since 4.8-
212-
213 Sets the native, platform specific, \a key for this shared memory object. If-
214 \a key is the same as the current native key, the function returns without-
215 doing anything. If all you want is to assign a key to a segment, you should-
216 call setKey() instead.-
217-
218 You can call nativeKey() to retrieve the native key. If a native key has been-
219 assigned, calling key() will return a null string.-
220-
221 If the shared memory object is attached to an underlying shared memory-
222 segment, it will \l {detach()} {detach} from it before setting the new key.-
223 This function does not do an attach().-
224-
225 The application will not be portable if you set a native key.-
226-
227 \sa nativeKey(), key(), isAttached()-
228*/-
229void QSharedMemory::setNativeKey(const QString &key)-
230{-
231 Q_D(QSharedMemory);-
232 if (key == d->nativeKey && d->key.isNull())
key == d->nativeKeyDescription
TRUEevaluated 2 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 7 times by 1 test
Evaluated by:
  • tst_QSharedMemory
d->key.isNull()Description
TRUEevaluated 2 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEnever evaluated
0-7
233 return;
executed 2 times by 1 test: return;
Executed by:
  • tst_QSharedMemory
2
234-
235 if (isAttached())
isAttached()Description
TRUEnever evaluated
FALSEevaluated 7 times by 1 test
Evaluated by:
  • tst_QSharedMemory
0-7
236 detach();
never executed: detach();
0
237 d->cleanHandle();-
238 d->key = QString();-
239 d->nativeKey = key;-
240}
executed 7 times by 1 test: end of block
Executed by:
  • tst_QSharedMemory
7
241-
242bool QSharedMemoryPrivate::initKey()-
243{-
244 if (!cleanHandle())
!cleanHandle()Description
TRUEnever evaluated
FALSEevaluated 3645 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
0-3645
245 return false;
never executed: return false;
0
246#ifndef QT_NO_SYSTEMSEMAPHORE-
247 systemSemaphore.setKey(QString(), 1);-
248 systemSemaphore.setKey(key, 1);-
249 if (systemSemaphore.error() != QSystemSemaphore::NoError) {
systemSemaphor...phore::NoErrorDescription
TRUEevaluated 54 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3591 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
54-3591
250 QString function = QLatin1String("QSharedMemoryPrivate::initKey");-
251 errorString = QSharedMemory::tr("%1: unable to set key on lock").arg(function);-
252 switch(systemSemaphore.error()) {-
253 case QSystemSemaphore::PermissionDenied:
never executed: case QSystemSemaphore::PermissionDenied:
0
254 error = QSharedMemory::PermissionDenied;-
255 break;
never executed: break;
0
256 case QSystemSemaphore::KeyError:
executed 52 times by 1 test: case QSystemSemaphore::KeyError:
Executed by:
  • tst_QSharedMemory
52
257 error = QSharedMemory::KeyError;-
258 break;
executed 52 times by 1 test: break;
Executed by:
  • tst_QSharedMemory
52
259 case QSystemSemaphore::AlreadyExists:
never executed: case QSystemSemaphore::AlreadyExists:
0
260 error = QSharedMemory::AlreadyExists;-
261 break;
never executed: break;
0
262 case QSystemSemaphore::NotFound:
never executed: case QSystemSemaphore::NotFound:
0
263 error = QSharedMemory::NotFound;-
264 break;
never executed: break;
0
265 case QSystemSemaphore::OutOfResources:
executed 2 times by 1 test: case QSystemSemaphore::OutOfResources:
Executed by:
  • tst_QSharedMemory
2
266 error = QSharedMemory::OutOfResources;-
267 break;
executed 2 times by 1 test: break;
Executed by:
  • tst_QSharedMemory
2
268 case QSystemSemaphore::UnknownError:
never executed: case QSystemSemaphore::UnknownError:
0
269 default:
never executed: default:
0
270 error = QSharedMemory::UnknownError;-
271 break;
never executed: break;
0
272 }-
273 return false;
executed 54 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
54
274 }-
275#endif-
276 errorString = QString();-
277 error = QSharedMemory::NoError;-
278 return true;
executed 3591 times by 2 tests: return true;
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
3591
279}-
280-
281/*!-
282 Returns the key assigned with setKey() to this shared memory, or a null key-
283 if no key has been assigned, or if the segment is using a nativeKey(). The-
284 key is the identifier used by Qt applications to identify the shared memory-
285 segment.-
286-
287 You can find the native, platform specific, key used by the operating system-
288 by calling nativeKey().-
289-
290 \sa setKey(), setNativeKey()-
291 */-
292QString QSharedMemory::key() const-
293{-
294 Q_D(const QSharedMemory);-
295 return d->key;
executed 48 times by 1 test: return d->key;
Executed by:
  • tst_QSharedMemory
48
296}-
297-
298/*!-
299 \since 4.8-
300-
301 Returns the native, platform specific, key for this shared memory object. The-
302 native key is the identifier used by the operating system to identify the-
303 shared memory segment.-
304-
305 You can use the native key to access shared memory segments that have not-
306 been created by Qt, or to grant shared memory access to non-Qt applications.-
307-
308 \sa setKey(), setNativeKey()-
309*/-
310QString QSharedMemory::nativeKey() const-
311{-
312 Q_D(const QSharedMemory);-
313 return d->nativeKey;
executed 39 times by 1 test: return d->nativeKey;
Executed by:
  • tst_QSharedMemory
39
314}-
315-
316/*!-
317 Creates a shared memory segment of \a size bytes with the key passed to the-
318 constructor, set with setKey() or set with setNativeKey(), then attaches to-
319 the new shared memory segment with the given access \a mode and returns-
320 \tt true. If a shared memory segment identified by the key already exists,-
321 the attach operation is not performed and \tt false is returned. When the-
322 return value is \tt false, call error() to determine which error occurred.-
323-
324 \sa error()-
325 */-
326bool QSharedMemory::create(int size, AccessMode mode)-
327{-
328 Q_D(QSharedMemory);-
329-
330 if (!d->initKey())
!d->initKey()Description
TRUEevaluated 1 time by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3521 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
1-3521
331 return false;
executed 1 time by 1 test: return false;
Executed by:
  • tst_QSharedMemory
1
332-
333#ifndef QT_NO_SYSTEMSEMAPHORE-
334#ifndef Q_OS_WIN-
335 // Take ownership and force set initialValue because the semaphore-
336 // might have already existed from a previous crash.-
337 d->systemSemaphore.setKey(d->key, 1, QSystemSemaphore::Create);-
338#endif-
339#endif-
340-
341 QString function = QLatin1String("QSharedMemory::create");-
342#ifndef QT_NO_SYSTEMSEMAPHORE-
343 QSharedMemoryLocker lock(this);-
344 if (!d->key.isNull() && !d->tryLocker(&lock, function))
!d->key.isNull()Description
TRUEevaluated 3468 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
FALSEevaluated 53 times by 1 test
Evaluated by:
  • tst_QSharedMemory
!d->tryLocker(&lock, function)Description
TRUEnever evaluated
FALSEevaluated 3468 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
0-3468
345 return false;
never executed: return false;
0
346#endif-
347-
348 if (size <= 0) {
size <= 0Description
TRUEevaluated 1 time by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3520 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
1-3520
349 d->error = QSharedMemory::InvalidSize;-
350 d->errorString =-
351 QSharedMemory::tr("%1: create size is less then 0").arg(function);-
352 return false;
executed 1 time by 1 test: return false;
Executed by:
  • tst_QSharedMemory
1
353 }-
354-
355 if (!d->create(size))
!d->create(size)Description
TRUEevaluated 55 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3465 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
55-3465
356 return false;
executed 55 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
55
357-
358 return d->attach(mode);
executed 3465 times by 2 tests: return d->attach(mode);
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
3465
359}-
360-
361/*!-
362 Returns the size of the attached shared memory segment. If no shared-
363 memory segment is attached, 0 is returned.-
364-
365 \sa create(), attach()-
366 */-
367int QSharedMemory::size() const-
368{-
369 Q_D(const QSharedMemory);-
370 return d->size;
executed 17 times by 1 test: return d->size;
Executed by:
  • tst_QSharedMemory
17
371}-
372-
373/*!-
374 \enum QSharedMemory::AccessMode-
375-
376 \value ReadOnly The shared memory segment is read-only. Writing to-
377 the shared memory segment is not allowed. An attempt to write to a-
378 shared memory segment created with ReadOnly causes the program to-
379 abort.-
380-
381 \value ReadWrite Reading and writing the shared memory segment are-
382 both allowed.-
383*/-
384-
385/*!-
386 Attempts to attach the process to the shared memory segment-
387 identified by the key that was passed to the constructor or to a-
388 call to setKey() or setNativeKey(). The access \a mode is \l {QSharedMemory::}-
389 {ReadWrite} by default. It can also be \l {QSharedMemory::}-
390 {ReadOnly}. Returns \c true if the attach operation is successful. If-
391 false is returned, call error() to determine which error occurred.-
392 After attaching the shared memory segment, a pointer to the shared-
393 memory can be obtained by calling data().-
394-
395 \sa isAttached(), detach(), create()-
396 */-
397bool QSharedMemory::attach(AccessMode mode)-
398{-
399 Q_D(QSharedMemory);-
400-
401 if (isAttached() || !d->initKey())
isAttached()Description
TRUEnever evaluated
FALSEevaluated 123 times by 1 test
Evaluated by:
  • tst_QSharedMemory
!d->initKey()Description
TRUEevaluated 53 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 70 times by 1 test
Evaluated by:
  • tst_QSharedMemory
0-123
402 return false;
executed 53 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
53
403#ifndef QT_NO_SYSTEMSEMAPHORE-
404 QSharedMemoryLocker lock(this);-
405 if (!d->key.isNull() && !d->tryLocker(&lock, QLatin1String("QSharedMemory::attach")))
!d->key.isNull()Description
TRUEevaluated 69 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 1 time by 1 test
Evaluated by:
  • tst_QSharedMemory
!d->tryLocker(...ory::attach"))Description
TRUEnever evaluated
FALSEevaluated 69 times by 1 test
Evaluated by:
  • tst_QSharedMemory
0-69
406 return false;
never executed: return false;
0
407#endif-
408-
409 if (isAttached() || !d->handle())
isAttached()Description
TRUEnever evaluated
FALSEevaluated 70 times by 1 test
Evaluated by:
  • tst_QSharedMemory
!d->handle()Description
TRUEevaluated 3 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 67 times by 1 test
Evaluated by:
  • tst_QSharedMemory
0-70
410 return false;
executed 3 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
3
411-
412 return d->attach(mode);
executed 67 times by 1 test: return d->attach(mode);
Executed by:
  • tst_QSharedMemory
67
413}-
414-
415/*!-
416 Returns \c true if this process is attached to the shared memory-
417 segment.-
418-
419 \sa attach(), detach()-
420 */-
421bool QSharedMemory::isAttached() const-
422{-
423 Q_D(const QSharedMemory);-
424 return (0 != d->memory);
executed 11064 times by 2 tests: return (0 != d->memory);
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
11064
425}-
426-
427/*!-
428 Detaches the process from the shared memory segment. If this was the-
429 last process attached to the shared memory segment, then the shared-
430 memory segment is released by the system, i.e., the contents are-
431 destroyed. The function returns \c true if it detaches the shared-
432 memory segment. If it returns \c false, it usually means the segment-
433 either isn't attached, or it is locked by another process.-
434-
435 \sa attach(), isAttached()-
436 */-
437bool QSharedMemory::detach()-
438{-
439 Q_D(QSharedMemory);-
440 if (!isAttached())
!isAttached()Description
TRUEevaluated 64 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 3531 times by 1 test
Evaluated by:
  • tst_QSharedMemory
64-3531
441 return false;
executed 64 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
64
442-
443#ifndef QT_NO_SYSTEMSEMAPHORE-
444 QSharedMemoryLocker lock(this);-
445 if (!d->key.isNull() && !d->tryLocker(&lock, QLatin1String("QSharedMemory::detach")))
!d->key.isNull()Description
TRUEevaluated 3531 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEnever evaluated
!d->tryLocker(...ory::detach"))Description
TRUEnever evaluated
FALSEevaluated 3531 times by 1 test
Evaluated by:
  • tst_QSharedMemory
0-3531
446 return false;
never executed: return false;
0
447#endif-
448-
449 return d->detach();
executed 3531 times by 1 test: return d->detach();
Executed by:
  • tst_QSharedMemory
3531
450}-
451-
452/*!-
453 Returns a pointer to the contents of the shared memory segment, if-
454 one is attached. Otherwise it returns null. Remember to lock the-
455 shared memory with lock() before reading from or writing to the-
456 shared memory, and remember to release the lock with unlock() after-
457 you are done.-
458-
459 \sa attach()-
460 */-
461void *QSharedMemory::data()-
462{-
463 Q_D(QSharedMemory);-
464 return d->memory;
executed 106 times by 2 tests: return d->memory;
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
106
465}-
466-
467/*!-
468 Returns a const pointer to the contents of the shared memory-
469 segment, if one is attached. Otherwise it returns null. Remember to-
470 lock the shared memory with lock() before reading from or writing to-
471 the shared memory, and remember to release the lock with unlock()-
472 after you are done.-
473-
474 \sa attach(), create()-
475 */-
476const void* QSharedMemory::constData() const-
477{-
478 Q_D(const QSharedMemory);-
479 return d->memory;
never executed: return d->memory;
0
480}-
481-
482/*!-
483 \overload data()-
484 */-
485const void *QSharedMemory::data() const-
486{-
487 Q_D(const QSharedMemory);-
488 return d->memory;
never executed: return d->memory;
0
489}-
490-
491#ifndef QT_NO_SYSTEMSEMAPHORE-
492/*!-
493 This is a semaphore that locks the shared memory segment for access-
494 by this process and returns \c true. If another process has locked the-
495 segment, this function blocks until the lock is released. Then it-
496 acquires the lock and returns \c true. If this function returns \c false,-
497 it means that you have ignored a false return from create() or attach(),-
498 that you have set the key with setNativeKey() or that-
499 QSystemSemaphore::acquire() failed due to an unknown system error.-
500-
501 \sa unlock(), data(), QSystemSemaphore::acquire()-
502 */-
503bool QSharedMemory::lock()-
504{-
505 Q_D(QSharedMemory);-
506 if (d->lockedByMe) {
d->lockedByMeDescription
TRUEevaluated 2 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 7581 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
2-7581
507 qWarning("QSharedMemory::lock: already locked");-
508 return true;
executed 2 times by 1 test: return true;
Executed by:
  • tst_QSharedMemory
2
509 }-
510 if (d->systemSemaphore.acquire()) {
d->systemSemaphore.acquire()Description
TRUEevaluated 7579 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
FALSEevaluated 2 times by 1 test
Evaluated by:
  • tst_QSharedMemory
2-7579
511 d->lockedByMe = true;-
512 return true;
executed 7579 times by 2 tests: return true;
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
7579
513 }-
514 QString function = QLatin1String("QSharedMemory::lock");-
515 d->errorString = QSharedMemory::tr("%1: unable to lock").arg(function);-
516 d->error = QSharedMemory::LockError;-
517 return false;
executed 2 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
2
518}-
519-
520/*!-
521 Releases the lock on the shared memory segment and returns \c true, if-
522 the lock is currently held by this process. If the segment is not-
523 locked, or if the lock is held by another process, nothing happens-
524 and false is returned.-
525-
526 \sa lock()-
527 */-
528bool QSharedMemory::unlock()-
529{-
530 Q_D(QSharedMemory);-
531 if (!d->lockedByMe)
!d->lockedByMeDescription
TRUEevaluated 54 times by 1 test
Evaluated by:
  • tst_QSharedMemory
FALSEevaluated 7578 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
54-7578
532 return false;
executed 54 times by 1 test: return false;
Executed by:
  • tst_QSharedMemory
54
533 d->lockedByMe = false;-
534 if (d->systemSemaphore.release())
d->systemSemaphore.release()Description
TRUEevaluated 7578 times by 2 tests
Evaluated by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
FALSEnever evaluated
0-7578
535 return true;
executed 7578 times by 2 tests: return true;
Executed by:
  • tst_QSharedMemory
  • tst_qsharedmemory - unknown status
7578
536 QString function = QLatin1String("QSharedMemory::unlock");-
537 d->errorString = QSharedMemory::tr("%1: unable to unlock").arg(function);-
538 d->error = QSharedMemory::LockError;-
539 return false;
never executed: return false;
0
540}-
541#endif // QT_NO_SYSTEMSEMAPHORE-
542-
543/*!-
544 \enum QSharedMemory::SharedMemoryError-
545-
546 \value NoError No error occurred.-
547-
548 \value PermissionDenied The operation failed because the caller-
549 didn't have the required permissions.-
550-
551 \value InvalidSize A create operation failed because the requested-
552 size was invalid.-
553-
554 \value KeyError The operation failed because of an invalid key.-
555-
556 \value AlreadyExists A create() operation failed because a shared-
557 memory segment with the specified key already existed.-
558-
559 \value NotFound An attach() failed because a shared memory segment-
560 with the specified key could not be found.-
561-
562 \value LockError The attempt to lock() the shared memory segment-
563 failed because create() or attach() failed and returned false, or-
564 because a system error occurred in QSystemSemaphore::acquire().-
565-
566 \value OutOfResources A create() operation failed because there was-
567 not enough memory available to fill the request.-
568-
569 \value UnknownError Something else happened and it was bad.-
570*/-
571-
572/*!-
573 Returns a value indicating whether an error occurred, and, if so,-
574 which error it was.-
575-
576 \sa errorString()-
577 */-
578QSharedMemory::SharedMemoryError QSharedMemory::error() const-
579{-
580 Q_D(const QSharedMemory);-
581 return d->error;
executed 23 times by 1 test: return d->error;
Executed by:
  • tst_QSharedMemory
23
582}-
583-
584/*!-
585 Returns a text description of the last error that occurred. If-
586 error() returns an \l {QSharedMemory::SharedMemoryError} {error-
587 value}, call this function to get a text string that describes the-
588 error.-
589-
590 \sa error()-
591 */-
592QString QSharedMemory::errorString() const-
593{-
594 Q_D(const QSharedMemory);-
595 return d->errorString;
executed 18 times by 1 test: return d->errorString;
Executed by:
  • tst_QSharedMemory
18
596}-
597-
598#endif // QT_NO_SHAREDMEMORY-
599-
600QT_END_NAMESPACE-
Source codeSwitch to Preprocessed file
Generated by Squish Coco Non-Commercial 4.3.0-BETA-master-30-08-2018-4cb69e9