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Diffstat (limited to 'framework/source/fwi/threadhelp')
-rw-r--r-- | framework/source/fwi/threadhelp/transactionmanager.cxx | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/framework/source/fwi/threadhelp/transactionmanager.cxx b/framework/source/fwi/threadhelp/transactionmanager.cxx new file mode 100644 index 000000000..7b6f930b5 --- /dev/null +++ b/framework/source/fwi/threadhelp/transactionmanager.cxx @@ -0,0 +1,219 @@ +/* -*- 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 . + */ + +#include <sal/config.h> +#include <sal/log.hxx> + +#include <threadhelp/transactionmanager.hxx> + +#include <com/sun/star/lang/DisposedException.hpp> + +namespace framework{ + +/*-************************************************************************************************************ + @short standard ctor + @descr Initialize instance with right start values for correct working. +*//*-*************************************************************************************************************/ +TransactionManager::TransactionManager() + : m_eWorkingMode ( E_INIT ) + , m_nTransactionCount ( 0 ) +{ + m_aBarrier.open(); +} + +/*-************************************************************************************************************ + @short standard dtor +*//*-*************************************************************************************************************/ +TransactionManager::~TransactionManager() +{ +} + +/*-**************************************************************************************************** + @short set new working mode + @descr These implementation knows for states of working: E_INIT, E_WORK, E_BEFORECLOSE, E_CLOSE + You can step during this ones only from the left to the right side and start at left side again! + (This is necessary e.g. for refcounted objects!) + This call will block till all current existing transactions was finished. + Following results can occur: + E_INIT : All requests on this implementation are refused. + It's your decision to react in a right way. + + E_WORK : The object can work now. The full functionality is available. + + E_BEFORECLOSE : The object start the closing mechanism ... but sometimes + e.g. the dispose() method need to call some private methods. + These some special methods should use E_SOFTEXCEPTIONS + to detect this special case! + + E_CLOSE : Object is already dead! All further requests will be refused. + It's your decision to react in a right way. + @param "eMode", is the new mode - but we don't accept setting mode in wrong order! + @onerror We do nothing. +*//*-*****************************************************************************************************/ +void TransactionManager::setWorkingMode( EWorkingMode eMode ) +{ + // Safe member access. + bool bWaitFor = false; + { + osl::MutexGuard aAccessGuard(m_aAccessLock); + // Change working mode first! + if ( + (m_eWorkingMode == E_INIT && eMode == E_WORK) || + ((m_eWorkingMode == E_WORK || m_eWorkingMode == E_INIT) && eMode == E_BEFORECLOSE) || + (m_eWorkingMode == E_BEFORECLOSE && eMode == E_CLOSE) || + (m_eWorkingMode == E_CLOSE && eMode == E_INIT) + ) + { + m_eWorkingMode = eMode; + if (m_eWorkingMode == E_BEFORECLOSE || m_eWorkingMode == E_CLOSE) + { + bWaitFor = true; + } + } + } + // Wait for current existing transactions then! + // (Only necessary for changing to E_BEFORECLOSE or E_CLOSE!... + // otherwise; if you wait at setting E_WORK another thread could finish an acquire-call during our unlock() and wait() call + // ... and we will wait forever here!!!) + // Don't forget to release access mutex before. + if( bWaitFor ) + { + m_aBarrier.wait(); + } +} + +/*-**************************************************************************************************** + @short get current working mode + @descr If you stand in your close() or init() method ... but don't know + if you called more than ones(!) ... you can use this function to get + right information. + e.g: You have a method init() which is used to change working mode from + E_INIT to E_WORK and should be used to initialize some member too ... + What should you do: + + void init( sal_Int32 nValue ) + { + // Reject this call if our transaction manager say: "Object already initialized!" + // Otherwise initialize your member. + if( m_aTransactionManager.getWorkingMode() == E_INIT ) + { + // Object is uninitialized ... + // Make member access threadsafe! + Guard aGuard( m_aMutex ); + + // Check working mode again .. because another instance could be faster. + // (It's possible to set this guard at first of this method too!) + if( m_aTransactionManager.getWorkingMode() == E_INIT ) + { + m_aMember = nValue; + + // Object is initialized now ... set working mode to E_WORK! + m_aTransactionManager.setWorkingMode( E_WORK ); + } + } + } + + @seealso method setWorkingMode() + @return Current set mode. + + @onerror No error should occur. +*//*-*****************************************************************************************************/ +EWorkingMode TransactionManager::getWorkingMode() const +{ + // Synchronize access to internal member! + ::osl::MutexGuard aAccessLock( m_aAccessLock ); + return m_eWorkingMode; +} + +/*-**************************************************************************************************** + @short start new transaction + @descr A guard should use this method to start a new transaction. He should look for rejected + calls to by using parameter eMode and eReason. + If call was not rejected your transaction will be non breakable during releasing your transaction + guard! BUT ... your code isn't threadsafe then! It's a transaction manager only... + + @seealso method unregisterTransaction() + + @param "eMode" ,used to enable/disable throwing exceptions automatically for rejected calls +*//*-*****************************************************************************************************/ +void TransactionManager::registerTransaction( EExceptionMode eMode ) +{ + ::osl::MutexGuard aAccessGuard( m_aAccessLock ); + switch( m_eWorkingMode ) + { + case E_INIT: + if( eMode == E_HARDEXCEPTIONS ) + { + // Help programmer to find out, why this exception is thrown! + SAL_WARN( "fwk", "TransactionManager...: Owner instance not correctly initialized yet. Call was rejected! Normally it's an algorithm error ... wrong use of class!" ); + //ATTENTION: temp. disabled - till all bad code positions are detected and changed! */ + // throw css::uno::RuntimeException( "TransactionManager.: Owner instance not right initialized yet. Call was rejected! Normally it's an algorithm error... wrong using of class!\n", css::uno::Reference< css::uno::XInterface >() ); + } + break; + case E_WORK: + break; + case E_BEFORECLOSE: + if( eMode == E_HARDEXCEPTIONS ) + { + // Help programmer to find out, why this exception is thrown! + SAL_WARN( "fwk", "TransactionManager...: Owner instance stand in close method. Call was rejected!" ); + throw css::lang::DisposedException( "TransactionManager: Owner instance stand in close method. Call was rejected!" ); + } + break; + case E_CLOSE: + // Help programmer to find out, why this exception is thrown! + SAL_WARN( "fwk", "TransactionManager...: Owner instance already closed. Call was rejected!" ); + throw css::lang::DisposedException( "TransactionManager: Owner instance already closed. Call was rejected!" ); + } + + // Register this new transaction. + // If it is the first one .. close gate to disable changing of working mode. + ++m_nTransactionCount; + if( m_nTransactionCount == 1 ) + { + m_aBarrier.close(); + } +} + +/*-**************************************************************************************************** + @short finish transaction + @descr A guard should call this method to release current transaction. + + @seealso method registerTransaction() +*//*-*****************************************************************************************************/ +void TransactionManager::unregisterTransaction() +{ + // This call could not rejected! + // Safe access to internal member. + ::osl::MutexGuard aAccessGuard( m_aAccessLock ); + + // Deregister this transaction. + // If it was the last one ... open gate to enable changing of working mode! + // (see setWorkingMode()) + + --m_nTransactionCount; + if( m_nTransactionCount == 0 ) + { + m_aBarrier.open(); + } +} + +} // namespace framework + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |