include/QtCore/qsharedmemory.h

0001 // Copyright (C) 2016 The Qt Company Ltd.
0002 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
0003
0004 #ifndef QSHAREDMEMORY_H
0005 #define QSHAREDMEMORY_H
0006
0007 #include <QtCore/qtipccommon.h>
0008 #ifndef QT_NO_QOBJECT
0009 # include <QtCore/qobject.h>
0010 #else
0011 # include <QtCore/qobjectdefs.h>
0012 # include <QtCore/qscopedpointer.h>
0013 # include <QtCore/qstring.h>
0014 #endif
0015
0016 QT_BEGIN_NAMESPACE
0017
0018 #if QT_CONFIG(sharedmemory)
0019
0020 class QSharedMemoryPrivate;
0021
0022 class Q_CORE_EXPORT QSharedMemory : public QObject
0023 {
0024     Q_OBJECT
0025     Q_DECLARE_PRIVATE(QSharedMemory)
0026
0027 public:
0028     enum AccessMode
0029     {
0030         ReadOnly,
0031         ReadWrite
0032     };
0033     Q_ENUM(AccessMode)
0034
0035     enum SharedMemoryError
0036     {
0037         NoError,
0038         PermissionDenied,
0039         InvalidSize,
0040         KeyError,
0041         AlreadyExists,
0042         NotFound,
0043         LockError,
0044         OutOfResources,
0045         UnknownError
0046     };
0047     Q_ENUM(SharedMemoryError)
0048
0049     QSharedMemory(QObject *parent = nullptr);
0050     QSharedMemory(const QNativeIpcKey &key, QObject *parent = nullptr);
0051     ~QSharedMemory();
0052
0053     QSharedMemory(const QString &key, QObject *parent = nullptr);
0054     void setKey(const QString &key);
0055     QString key() const;
0056
0057     void setNativeKey(const QNativeIpcKey &key);
0058     void setNativeKey(const QString &key, QNativeIpcKey::Type type = QNativeIpcKey::legacyDefaultTypeForOs())
0059     { setNativeKey({ key, type }); }
0060     QString nativeKey() const;
0061     QNativeIpcKey nativeIpcKey() const;
0062 #if QT_CORE_REMOVED_SINCE(6, 5)
0063     void setNativeKey(const QString &key);
0064 #endif
0065
0066     bool create(qsizetype size, AccessMode mode = ReadWrite);
0067     qsizetype size() const;
0068
0069     bool attach(AccessMode mode = ReadWrite);
0070     bool isAttached() const;
0071     bool detach();
0072
0073     void *data();
0074     const void* constData() const;
0075     const void *data() const;
0076
0077 #if QT_CONFIG(systemsemaphore)
0078     bool lock();
0079     bool unlock();
0080 #endif
0081
0082     SharedMemoryError error() const;
0083     QString errorString() const;
0084
0085     static bool isKeyTypeSupported(QNativeIpcKey::Type type) Q_DECL_CONST_FUNCTION;
0086     static QNativeIpcKey platformSafeKey(const QString &key,
0087             QNativeIpcKey::Type type = QNativeIpcKey::DefaultTypeForOs);
0088     static QNativeIpcKey legacyNativeKey(const QString &key,
0089             QNativeIpcKey::Type type = QNativeIpcKey::legacyDefaultTypeForOs());
0090
0091 private:
0092     Q_DISABLE_COPY(QSharedMemory)
0093 };
0094
0095 #endif // QT_CONFIG(sharedmemory)
0096
0097 QT_END_NAMESPACE
0098
0099 #endif // QSHAREDMEMORY_H