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Diffstat (limited to 'src/corelib/ipc/qtipccommon_p.h')
| -rw-r--r-- | src/corelib/ipc/qtipccommon_p.h | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/src/corelib/ipc/qtipccommon_p.h b/src/corelib/ipc/qtipccommon_p.h new file mode 100644 index 0000000000..72762c5ba7 --- /dev/null +++ b/src/corelib/ipc/qtipccommon_p.h @@ -0,0 +1,173 @@ +// 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 QTIPCCOMMON_P_H +#define QTIPCCOMMON_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 "qtipccommon.h" +#include <private/qglobal_p.h> +#include <private/qtcore-config_p.h> + +#if QT_CONFIG(sharedmemory) || QT_CONFIG(systemsemaphore) + +#if defined(Q_OS_UNIX) +# include <qfile.h> +# include <private/qcore_unix_p.h> +#endif + +QT_BEGIN_NAMESPACE + +class QNativeIpcKeyPrivate +{ +public: + QString legacyKey_; + + static QString legacyKey(const QNativeIpcKey &key) + { + if (key.isSlowPath()) + return key.d->legacyKey_; + return QString(); + } + static void setLegacyKey(QNativeIpcKey &key, const QString &legacyKey) + { + QNativeIpcKeyPrivate::makeExtended(key)->legacyKey_ = legacyKey; + } + static void setNativeAndLegacyKeys(QNativeIpcKey &key, const QString &nativeKey, + const QString &legacyKey) + { + key.setNativeKey(nativeKey); + setLegacyKey(key, legacyKey); + } + +private: + static QNativeIpcKeyPrivate *makeExtended(QNativeIpcKey &key) + { + if (!key.isSlowPath()) + key.d = new QNativeIpcKeyPrivate; + return key.d; + } +}; + +namespace QtIpcCommon { +enum class IpcType { + SharedMemory, + SystemSemaphore +}; + +static constexpr bool isIpcSupported(IpcType ipcType, QNativeIpcKey::Type type) +{ + switch (type) { + case QNativeIpcKey::Type::SystemV: + break; + + case QNativeIpcKey::Type::PosixRealtime: + if (ipcType == IpcType::SharedMemory) + return QT_CONFIG(posix_shm); + return QT_CONFIG(posix_sem); + + case QNativeIpcKey::Type::Windows: +#ifdef Q_OS_WIN + return true; +#else + return false; +#endif + } + + if (ipcType == IpcType::SharedMemory) + return QT_CONFIG(sysv_shm); + return QT_CONFIG(sysv_sem); +} + +template <auto Member1, auto... Members> class IpcStorageVariant +{ + template <typename T, typename C> static C extractClass(T C::*); + template <typename T, typename C> static T extractObject(T C::*); + + template <auto M> + static constexpr bool IsEnabled = decltype(extractObject(M))::Enabled; + + static_assert(std::is_member_object_pointer_v<decltype(Member1)>); + using StorageType = decltype(extractClass(Member1)); + StorageType d; + +public: + template <typename Lambda> static auto + visit_internal(StorageType &storage, QNativeIpcKey::Type keyType, const Lambda &lambda) + { + if constexpr ((IsEnabled<Member1> || ... || IsEnabled<Members>)) { + if constexpr (IsEnabled<Member1>) { + using MemberType1 = decltype(extractObject(Member1)); + if (MemberType1::supports(keyType)) + return lambda(&(storage.*Member1)); + } + if constexpr ((... || IsEnabled<Members>)) + return IpcStorageVariant<Members...>::visit_internal(storage, keyType, lambda); + Q_UNREACHABLE(); + } else { + // no backends enabled, but we can't return void + return false; + } + } + + template <typename Lambda> auto visit(QNativeIpcKey::Type keyType, const Lambda &lambda) + { + return visit_internal(d, keyType, lambda); + } + + template <typename Lambda> static auto + staticVisit(QNativeIpcKey::Type keyType, const Lambda &lambda) + { + if constexpr ((IsEnabled<Member1> || ... || IsEnabled<Members>)) { + if constexpr (IsEnabled<Member1>) { + using MemberType1 = decltype(extractObject(Member1)); + if (MemberType1::supports(keyType)) + return lambda(static_cast<MemberType1 *>(nullptr)); + } + if constexpr ((... || IsEnabled<Members>)) + return IpcStorageVariant<Members...>::staticVisit(keyType, lambda); + Q_UNREACHABLE(); + } else { + // no backends enabled, but we can't return void + return false; + } + } +}; + +QNativeIpcKey legacyPlatformSafeKey(const QString &key, IpcType ipcType, QNativeIpcKey::Type type); +QNativeIpcKey platformSafeKey(const QString &key, IpcType ipcType, QNativeIpcKey::Type type); + +#ifdef Q_OS_UNIX +// Convenience function to create the file if needed +inline int createUnixKeyFile(const QByteArray &fileName) +{ + int fd = qt_safe_open(fileName.constData(), O_EXCL | O_CREAT | O_RDWR, 0640); + if (fd < 0) { + if (errno == EEXIST) + return 0; + return -1; + } else { + close(fd); + } + return 1; + +} +#endif // Q_OS_UNIX +} // namespace QtIpcCommon + +QT_END_NAMESPACE + +#endif // QT_CONFIG(sharedmemory) || QT_CONFIG(systemsemaphore) + + +#endif // QTIPCCOMMON_P_H |