/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ /* * This file is part of the LibreOffice project. * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. * * This file incorporates work covered by the following license notice: * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed * with this work for additional information regarding copyright * ownership. The ASF licenses this file to you under the Apache * License, Version 2.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.apache.org/licenses/LICENSE-2.0 . */ #ifndef INCLUDED_FRAMEWORK_UNDOMANAGERHELPER_HXX #define INCLUDED_FRAMEWORK_UNDOMANAGERHELPER_HXX #include #include #include #include #include namespace com::sun::star::document { class XUndoAction; } namespace com::sun::star::document { class XUndoManager; } namespace com::sun::star::document { class XUndoManagerListener; } namespace com::sun::star::util { class XModifyListener; } namespace framework { class IMutex; } class SfxUndoManager; namespace framework { //= IMutexGuard class SAL_NO_VTABLE IMutexGuard { public: /** clears the lock. If the guard does not currently hold the lock, nothing happens. */ virtual void clear() = 0; /** returns the mutex guarded by the instance. Even if the guard currently has not a lock on the mutex, this method must succeed. */ virtual IMutex& getGuardedMutex() = 0; protected: ~IMutexGuard() {} }; //= IUndoManagerImplementation class SAL_NO_VTABLE IUndoManagerImplementation { public: /** returns the SfxUndoManager interface to the actual Undo stack @throws css::lang::DisposedException when the instance is already disposed, and no SfxUndoManager can be provided @throws css::lang::NotInitializedException when the instance is not initialized, yet, and no SfxUndoManager can be provided */ virtual SfxUndoManager& getImplUndoManager() = 0; /** provides access to a UNO interface for the XUndoManager implementation. Used when throwing exceptions. */ virtual css::uno::Reference< css::document::XUndoManager > getThis() = 0; protected: ~IUndoManagerImplementation() {} }; //= UndoManagerHelper class UndoManagerHelper_Impl; /** helper class for implementing an XUndoManager Several of the methods of the class take an IMutexGuard instance. It is assumed that this guard has a lock on its mutex at the moment the method is entered. The lock will be released before any notifications to the registered XUndoManagerListeners happen. The following locking strategy is used for this mutex:

Any notifications to the registered XUndoManagerListeners are after the guard has been cleared. i.e. without the mutex being locked.
Any calls into the SfxUndoManager implementation is made without the mutex being locked. Note that this implies that the SfxUndoManager implementation must be thread-safe in itself (which is true for the default implementation, SfxUndoManager).
An exception to the previous item are the SfxUndoManager::Undo and SfxUndoManager::Redo methods: They're called with the given external mutex being locked.

The reason for the exception for SfxUndoManager::Undo and SfxUndoManager::Redo is that those are expected to modify the actual document which the UndoManager works for. And as long as our documents are not thread-safe, and as long as we do not re-fit all existing SfxUndoImplementations to not expect the dreaded SolarMutex being locked when they're called, the above behavior is a compromise between "how it should be" and "how it can realistically be". */ class UNLESS_MERGELIBS_MORE(FWK_DLLPUBLIC) UndoManagerHelper { public: UndoManagerHelper( IUndoManagerImplementation& i_undoManagerImpl ); ~UndoManagerHelper(); // life time control void disposing(); // XUndoManager equivalents void enterUndoContext( const OUString& i_title, IMutexGuard& i_instanceLock ); void enterHiddenUndoContext( IMutexGuard& i_instanceLock ); void leaveUndoContext( IMutexGuard& i_instanceLock ); void addUndoAction( const css::uno::Reference< css::document::XUndoAction >& i_action, IMutexGuard& i_instanceLock ); void undo( IMutexGuard& i_instanceLock ); void redo( IMutexGuard& i_instanceLock ); bool isUndoPossible() const; bool isRedoPossible() const; OUString getCurrentUndoActionTitle() const; OUString getCurrentRedoActionTitle() const; css::uno::Sequence< OUString > getAllUndoActionTitles() const; css::uno::Sequence< OUString > getAllRedoActionTitles() const; void clear( IMutexGuard& i_instanceLock ); void clearRedo( IMutexGuard& i_instanceLock ); void reset( IMutexGuard& i_instanceLock ); void addUndoManagerListener( const css::uno::Reference< css::document::XUndoManagerListener >& i_listener ); void removeUndoManagerListener( const css::uno::Reference< css::document::XUndoManagerListener >& i_listener ); // XLockable, base of XUndoManager, equivalents void lock(); void unlock(); bool isLocked(); // XModifyBroadcaster equivalents void addModifyListener( const css::uno::Reference< css::util::XModifyListener >& i_listener ); void removeModifyListener( const css::uno::Reference< css::util::XModifyListener >& i_listener ); private: std::unique_ptr< UndoManagerHelper_Impl > m_xImpl; }; } // namespace framework #endif // INCLUDED_FRAMEWORK_UNDOMANAGERHELPER_HXX /* vim:set shiftwidth=4 softtabstop=4 expandtab: */ e-7-4+backports LibreOffice 核心代码仓库文档基金会

path: root/dbaccess/README.md

Age	Commit message (Expand)	Author
2021-04-07	Updated README.md files to represent current code / use Markdown format	Hossein
2021-03-24	Using .md extension/Markdown syntax for modules README	Hossein