Adding upstream version 1:7.0.4.upstream/1%7.0.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 135 insertions, 0 deletions

diff --git a/dbaccess/source/sdbtools/inc/connectiondependent.hxx b/dbaccess/source/sdbtools/inc/connectiondependent.hxx
new file mode 100644
index 000000000..d315d7018
--- /dev/null
+++ b/dbaccess/source/sdbtools/inc/connectiondependent.hxx
@@ -0,0 +1,135 @@
+/* -*- 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 .
+ */
+
+#pragma once
+
+#include <com/sun/star/sdbc/XConnection.hpp>
+#include <com/sun/star/lang/DisposedException.hpp>
+#include <com/sun/star/uno/XComponentContext.hpp>
+
+#include <cppuhelper/weakref.hxx>
+#include <osl/mutex.hxx>
+
+namespace sdbtools
+{
+
+    // ConnectionDependentComponent
+    class ConnectionDependentComponent
+    {
+    private:
+        mutable ::osl::Mutex    m_aMutex;
+        css::uno::WeakReference< css::sdbc::XConnection >
+                                m_aConnection;
+        css::uno::Reference< css::uno::XComponentContext >
+                                m_aContext;
+
+        /** a hard reference to the connection we're working for
+
+            This member is only valid as long as a EntryGuard is on the stack.
+            The guard will, in its constructor, set the member, and reset it in its destructor.
+            This ensures that the connection is only held hard when it's needed, and weak otherwise.
+        */
+        css::uno::Reference< css::sdbc::XConnection >
+                                m_xConnection;
+
+    protected:
+        ::osl::Mutex&   getMutex() const { return m_aMutex; }
+
+        const css::uno::Reference< css::uno::XComponentContext >&
+                        getContext() const { return m_aContext; }
+
+    protected:
+        class EntryGuard;
+
+    protected:
+        explicit ConnectionDependentComponent( const css::uno::Reference< css::uno::XComponentContext > & _rContext )
+            :m_aContext( _rContext )
+        {
+        }
+
+        /** sets the connection we depend on.
+
+            To be called exactly once.
+
+            @param  _rxConnection
+                the connection to set
+        */
+        void    setWeakConnection( const css::uno::Reference< css::sdbc::XConnection >& _rxConnection )
+        {
+            m_aConnection = _rxConnection;
+        }
+
+        const css::uno::Reference< css::sdbc::XConnection >&
+                getConnection() const { return m_xConnection; }
+
+    public:
+    struct GuardAccess;
+    friend struct GuardAccess;
+        /** helper for granting exclusive access to various other methods
+        */
+        struct GuardAccess { friend class EntryGuard; private: GuardAccess() { } };
+
+        ::osl::Mutex&   getMutex( GuardAccess ) const { return m_aMutex; }
+
+        bool acquireConnection( GuardAccess )
+        {
+            m_xConnection.set(m_aConnection);
+            return m_xConnection.is();
+        }
+        void releaseConnection( GuardAccess )
+        {
+            m_xConnection.clear();
+        }
+    };
+
+    // ConnectionDependentComponent::EntryGuard
+    /** a class for guarding methods of a connection-dependent component
+
+        This class serves multiple purposes:
+        <ul><li>It ensures multi-threading safety by guarding the component's mutex
+                as long as it lives.</li>
+            <li>It ensures that the component's connection is alive. The constructor
+                throws a DisposedException if no hard reference to the connection can
+                be obtained.</li>
+        </ul>
+    */
+    class ConnectionDependentComponent::EntryGuard
+    {
+    private:
+        ::osl::MutexGuard               m_aMutexGuard;
+        ConnectionDependentComponent&   m_rComponent;
+
+    public:
+        explicit EntryGuard( ConnectionDependentComponent& _rComponent )
+            :m_aMutexGuard( _rComponent.getMutex( ConnectionDependentComponent::GuardAccess() ) )
+            ,m_rComponent( _rComponent )
+        {
+            if ( !m_rComponent.acquireConnection( ConnectionDependentComponent::GuardAccess() ) )
+                throw css::lang::DisposedException();
+        }
+
+        ~EntryGuard()
+        {
+            m_rComponent.releaseConnection( ConnectionDependentComponent::GuardAccess() );
+        }
+    };
+
+} // namespace sdbtools
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */