1 files changed, 152 insertions, 0 deletions
diff --git a/src/corelib/ipc/qsystemsemaphore_p.h b/src/corelib/ipc/qsystemsemaphore_p.h
new file mode 100644
index 0000000000..788c4fb784
--- /dev/null
+++ b/src/corelib/ipc/qsystemsemaphore_p.h
@@ -0,0 +1,152 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2022 Intel Corporation.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QSYSTEMSEMAPHORE_P_H
+#define QSYSTEMSEMAPHORE_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qsystemsemaphore.h"
+
+#if QT_CONFIG(systemsemaphore)
+
+#include "qcoreapplication.h"
+#include "qtipccommon_p.h"
+#include "private/qtcore-config_p.h"
+
+#include <sys/types.h>
+#if QT_CONFIG(posix_sem)
+#  include <semaphore.h>
+#endif
+#ifndef SEM_FAILED
+#  define SEM_FAILED     nullptr
+struct sem_t;
+#endif
+#if QT_CONFIG(sysv_sem)
+#  include <sys/sem.h>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+class QSystemSemaphorePrivate;
+
+struct QSystemSemaphorePosix
+{
+    static constexpr bool Enabled = QT_CONFIG(posix_sem);
+    static bool supports(QNativeIpcKey::Type type)
+    { return type == QNativeIpcKey::Type::PosixRealtime; }
+    static bool runtimeSupportCheck();
+
+    bool handle(QSystemSemaphorePrivate *self, QSystemSemaphore::AccessMode mode);
+    void cleanHandle(QSystemSemaphorePrivate *self);
+    bool modifySemaphore(QSystemSemaphorePrivate *self, int count);
+
+    sem_t *semaphore = SEM_FAILED;
+    bool createdSemaphore = false;
+};
+
+struct QSystemSemaphoreSystemV
+{
+    static constexpr bool Enabled = QT_CONFIG(sysv_sem);
+    static bool supports(QNativeIpcKey::Type type)
+    { return quint16(type) <= 0xff; }
+    static bool runtimeSupportCheck();
+
+#if QT_CONFIG(sysv_sem)
+    key_t handle(QSystemSemaphorePrivate *self, QSystemSemaphore::AccessMode mode);
+    void cleanHandle(QSystemSemaphorePrivate *self);
+    bool modifySemaphore(QSystemSemaphorePrivate *self, int count);
+
+    QByteArray nativeKeyFile;
+    key_t unix_key = -1;
+    int semaphore = -1;
+    bool createdFile = false;
+    bool createdSemaphore = false;
+#endif
+};
+
+struct QSystemSemaphoreWin32
+{
+#ifdef Q_OS_WIN32
+    static constexpr bool Enabled = true;
+#else
+    static constexpr bool Enabled = false;
+#endif
+    static bool supports(QNativeIpcKey::Type type)
+    { return type == QNativeIpcKey::Type::Windows; }
+    static bool runtimeSupportCheck() { return Enabled; }
+
+    // we can declare the members without the #if
+    Qt::HANDLE handle(QSystemSemaphorePrivate *self, QSystemSemaphore::AccessMode mode);
+    void cleanHandle(QSystemSemaphorePrivate *self);
+    bool modifySemaphore(QSystemSemaphorePrivate *self, int count);
+
+    Qt::HANDLE semaphore = nullptr;
+};
+
+class QSystemSemaphorePrivate
+{
+public:
+    QSystemSemaphorePrivate(QNativeIpcKey::Type type) : nativeKey(type)
+    { constructBackend(); }
+    ~QSystemSemaphorePrivate() { destructBackend(); }
+
+    void setWindowsErrorString(QLatin1StringView function);    // Windows only
+    void setUnixErrorString(QLatin1StringView function);
+    inline void setError(QSystemSemaphore::SystemSemaphoreError e, const QString &message)
+    { error = e; errorString = message; }
+    inline void clearError()
+    { setError(QSystemSemaphore::NoError, QString()); }
+
+    QNativeIpcKey nativeKey;
+    QString errorString;
+    int initialValue;
+    QSystemSemaphore::SystemSemaphoreError error = QSystemSemaphore::NoError;
+
+    union Backend {
+        Backend() {}
+        ~Backend() {}
+        QSystemSemaphorePosix posix;
+        QSystemSemaphoreSystemV sysv;
+        QSystemSemaphoreWin32 win32;
+    };
+    QtIpcCommon::IpcStorageVariant<&Backend::posix, &Backend::sysv, &Backend::win32> backend;
+
+    void constructBackend();
+    void destructBackend();
+
+    template <typename Lambda> auto visit(const Lambda &lambda)
+    {
+        return backend.visit(nativeKey.type(), lambda);
+    }
+
+    void handle(QSystemSemaphore::AccessMode mode)
+    {
+        visit([&](auto p) { p->handle(this, mode); });
+    }
+    void cleanHandle()
+    {
+        visit([&](auto p) { p->cleanHandle(this); });
+    }
+    bool modifySemaphore(int count)
+    {
+        return visit([&](auto p) { return p->modifySemaphore(this, count); });
+    }
+};
+
+QT_END_NAMESPACE
+
+#endif // QT_CONFIG(systemsemaphore)
+
+#endif // QSYSTEMSEMAPHORE_P_H
+