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40
41#ifndef QLIBRARY_P_H
42#define QLIBRARY_P_H
43
44//
45// W A R N I N G
46// -------------
47//
48// This file is not part of the Qt API. It exists for the convenience
49// of the QLibrary class. This header file may change from
50// version to version without notice, or even be removed.
51//
52// We mean it.
53//
54
55#include <QtCore/private/qglobal_p.h>
56#include "QtCore/qlibrary.h"
57#include "QtCore/qmutex.h"
58#include "QtCore/qpointer.h"
59#include "QtCore/qstringlist.h"
60#include "QtCore/qplugin.h"
61#ifdef Q_OS_WIN
62# include "QtCore/qt_windows.h"
63#endif
64
65QT_REQUIRE_CONFIG(library);
66
67QT_BEGIN_NAMESPACE
68
69bool qt_debug_component();
70
71class QLibraryStore;
72class QLibraryPrivate
73{
74public:
75#ifdef Q_OS_WIN
76 using Handle = HINSTANCE;
77#else
78 using Handle = void *;
79#endif
80 enum UnloadFlag { UnloadSys, NoUnloadSys };
81
82 const QString fileName;
83 const QString fullVersion;
84
85 bool load();
86 QtPluginInstanceFunction loadPlugin(); // loads and resolves instance
87 bool unload(UnloadFlag flag = UnloadSys);
88 void release();
89 QFunctionPointer resolve(const char *);
90
91 QLibrary::LoadHints loadHints() const
92 { return QLibrary::LoadHints(loadHintsInt.loadRelaxed()); }
93 void setLoadHints(QLibrary::LoadHints lh);
94 QObject *pluginInstance();
95
96 static QLibraryPrivate *findOrCreate(const QString &fileName, const QString &version = QString(),
97 QLibrary::LoadHints loadHints = { });
98 static QStringList suffixes_sys(const QString &fullVersion);
99 static QStringList prefixes_sys();
100
101 QAtomicPointer<std::remove_pointer<QtPluginInstanceFunction>::type> instanceFactory;
102 QAtomicPointer<std::remove_pointer<Handle>::type> pHnd;
103
104 // the mutex protects the fields below
105 QMutex mutex;
106 QPointer<QObject> inst; // used by QFactoryLoader
107 QJsonObject metaData;
108 QString errorString;
109 QString qualifiedFileName;
110
111 void updatePluginState();
112 bool isPlugin();
113
114private:
115 explicit QLibraryPrivate(const QString &canonicalFileName, const QString &version, QLibrary::LoadHints loadHints);
116 ~QLibraryPrivate();
117 void mergeLoadHints(QLibrary::LoadHints loadHints);
118
119 bool load_sys();
120 bool unload_sys();
121 QFunctionPointer resolve_sys(const char *);
122
123 QAtomicInt loadHintsInt;
124
125 /// counts how many QLibrary or QPluginLoader are attached to us, plus 1 if it's loaded
126 QAtomicInt libraryRefCount;
127 /// counts how many times load() or loadPlugin() were called
128 QAtomicInt libraryUnloadCount;
129
130 enum { IsAPlugin, IsNotAPlugin, MightBeAPlugin } pluginState;
131 friend class QLibraryStore;
132};
133
134QT_END_NAMESPACE
135
136#endif // QLIBRARY_P_H
137

source code of qtbase/src/corelib/plugin/qlibrary_p.h