| /************************************************************** |
| * |
| * 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 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| *************************************************************/ |
| |
| |
| |
| // MARKER(update_precomp.py): autogen include statement, do not remove |
| #include "precompiled_framework.hxx" |
| |
| //_________________________________________________________________________________________________________________ |
| // my own includes |
| //_________________________________________________________________________________________________________________ |
| #include <threadhelp/lockhelper.hxx> |
| #include <general.h> |
| #include <macros/debug.hxx> |
| |
| #include <macros/generic.hxx> |
| |
| //_________________________________________________________________________________________________________________ |
| // interface includes |
| //_________________________________________________________________________________________________________________ |
| |
| //_________________________________________________________________________________________________________________ |
| // other includes |
| //_________________________________________________________________________________________________________________ |
| #include <vos/process.hxx> |
| |
| //_________________________________________________________________________________________________________________ |
| // namespace |
| //_________________________________________________________________________________________________________________ |
| |
| namespace framework{ |
| |
| //_________________________________________________________________________________________________________________ |
| // const |
| //_________________________________________________________________________________________________________________ |
| |
| //_________________________________________________________________________________________________________________ |
| // declarations |
| //_________________________________________________________________________________________________________________ |
| |
| /*-************************************************************************************************************//** |
| @short use ctor to initialize instance |
| @descr We must initialize our member "m_eLockType". This value specify handling of locking. |
| User use this helper as parameter for a guard creation. |
| These guard use "m_eLockType" to set lock in the right way by using right mutex or rw-lock. |
| |
| @seealso enum ELockType |
| @seealso class ReadGuard |
| @seealso class WriteGuard |
| |
| @param "rSolarMutex", for some components we must be "vcl-free"! So we can't work with our solar mutex |
| directly. User must set his reference at this instance - so we can work with it! |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| LockHelper::LockHelper( ::vos::IMutex* pSolarMutex ) |
| : m_pFairRWLock ( NULL ) |
| , m_pOwnMutex ( NULL ) |
| , m_pSolarMutex ( NULL ) |
| , m_pShareableOslMutex( NULL ) |
| , m_bDummySolarMutex ( sal_False ) |
| { |
| m_eLockType = implts_getLockType(); |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex = new ::osl::Mutex; |
| } |
| break; |
| case E_SOLARMUTEX : { |
| if( pSolarMutex == NULL ) |
| { |
| m_pSolarMutex = new ::vos::OMutex; |
| m_bDummySolarMutex = sal_True; |
| } |
| else |
| { |
| m_pSolarMutex = pSolarMutex; |
| } |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock = new FairRWLock; |
| } |
| break; |
| #ifdef ENABLE_ASSERTIONS |
| default : LOG_ASSERT2( m_eLockType!=E_NOTHING, "LockHelper::ctor()", "Invalid lock type found .. so code will not be threadsafe!" ) |
| #endif |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @short default dtor to release safed pointer |
| @descr We have created dynamical mutex- or lock-member ... or we hold a pointer to external objects. |
| We must release it! |
| |
| @seealso ctor() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| LockHelper::~LockHelper() |
| { |
| if( m_pShareableOslMutex != NULL ) |
| { |
| // Sometimes we hold two pointer to same object! |
| // (e.g. if m_eLockType==E_OWNMUTEX!) |
| // So we should forget it ... but don't delete it twice! |
| if( m_pShareableOslMutex != m_pOwnMutex ) |
| { |
| delete m_pShareableOslMutex; |
| } |
| m_pShareableOslMutex = NULL; |
| } |
| if( m_pOwnMutex != NULL ) |
| { |
| delete m_pOwnMutex; |
| m_pOwnMutex = NULL; |
| } |
| if( m_pSolarMutex != NULL ) |
| { |
| if (m_bDummySolarMutex) |
| { |
| delete static_cast<vos::OMutex*>(m_pSolarMutex); |
| m_bDummySolarMutex = sal_False; |
| } |
| m_pSolarMutex = NULL; |
| } |
| if( m_pFairRWLock != NULL ) |
| { |
| delete m_pFairRWLock; |
| m_pFairRWLock = NULL; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IMutex |
| @short set an exclusiv lock |
| @descr We must match this lock call with current set lock type and used lock member. |
| If a mutex should be used - it will be easy ... but if a rw-lock should be used |
| we must simulate it as a write access! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method acquireWriteAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::acquire() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->acquire(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->acquire(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->acquireWriteAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IMutex |
| @short release exclusiv lock |
| @descr We must match this unlock call with current set lock type and used lock member. |
| If a mutex should be used - it will be easy ... but if a rw-lock should be used |
| we must simulate it as a write access! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method releaseWriteAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::release() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->release(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->release(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->releaseWriteAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IRWLock |
| @short set lock for reading |
| @descr A guard should call this method to acquire read access on your member. |
| Writing isn't allowed then - but nobody could check it for you! |
| We use m_eLockType to differ between all possible "lock-member"!!! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method releaseReadAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::acquireReadAccess() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->acquire(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->acquire(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->acquireReadAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IRWLock |
| @short reset lock for reading |
| @descr A guard should call this method to release read access on your member. |
| We use m_eLockType to differ between all possible "lock-member"!!! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method acquireReadAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::releaseReadAccess() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->release(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->release(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->releaseReadAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IRWLock |
| @short set lock for writing |
| @descr A guard should call this method to acquire write access on your member. |
| Reading is allowed too - of course. |
| After successfully calling of this method you are the only writer. |
| We use m_eLockType to differ between all possible "lock-member"!!! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method releaseWriteAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::acquireWriteAccess() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->acquire(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->acquire(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->acquireWriteAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IRWLock |
| @short reset lock for writing |
| @descr A guard should call this method to release write access on your member. |
| We use m_eLockType to differ between all possible "lock-member"!!! |
| |
| @attention If a shareable osl mutex exist, he must be used as twice! |
| It's necessary for some cppu-helper classes ... |
| |
| @seealso method acquireWriteAccess() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::releaseWriteAccess() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : { |
| m_pOwnMutex->release(); |
| } |
| break; |
| case E_SOLARMUTEX : { |
| m_pSolarMutex->release(); |
| } |
| break; |
| case E_FAIRRWLOCK : { |
| m_pFairRWLock->releaseWriteAccess(); |
| } |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @interface IRWLock |
| @short downgrade a write access to a read access |
| @descr A guard should call this method to change a write to a read access. |
| New readers can work too - new writer are blocked! |
| We use m_eLockType to differ between all possible "lock-member"!!! |
| |
| @attention Ignore shareable mutex(!) - because this call never should release a lock completly! |
| We change a write access to a read access only. |
| |
| @attention a) Don't call this method if you are not a writer! |
| Results are not defined then ... |
| An upgrade can't be implemented really ... because acquiring new access |
| will be the same - there no differences! |
| b) Without function if m_eLockTyp is different from E_FAIRRWLOCK(!) ... |
| because, a mutex don't support it really. |
| |
| @seealso - |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*************************************************************************************************************/ |
| void LockHelper::downgradeWriteAccess() |
| { |
| switch( m_eLockType ) |
| { |
| case E_NOTHING : break; // There is nothing to do ... |
| case E_OWNMUTEX : break; // Not supported for mutex! |
| case E_SOLARMUTEX : break; // Not supported for mutex! |
| case E_FAIRRWLOCK : m_pFairRWLock->downgradeWriteAccess(); |
| break; |
| } |
| } |
| |
| /*-************************************************************************************************************//** |
| @short return a reference to a static lock helper |
| @descr Sometimes we need the global mutex or rw-lock! (e.g. in our own static methods) |
| But it's not a good idea to use these global one very often ... |
| That's why we use this little helper method. |
| We create our own "class global static" lock. |
| It will be created at first call only! |
| All other requests use these created one then directly. |
| |
| @seealso - |
| |
| @param - |
| @return A reference to a static mutex/lock member. |
| |
| @onerror No error should occur. |
| *//*-*************************************************************************************************************/ |
| LockHelper& LockHelper::getGlobalLock( ::vos::IMutex* pSolarMutex ) |
| { |
| // Initialize static "member" only for one time! |
| // Algorithm: |
| // a) Start with an invalid lock (NULL pointer) |
| // b) If these method first called (lock not already exist!) ... |
| // c) ... we must create a new one. Protect follow code with the global mutex - |
| // (It must be - we create a static variable!) |
| // d) Check pointer again - because ... another instance of our class could be faster then these one! |
| // e) Create the new lock and set it for return on static variable. |
| // f) Return new created or already existing lock object. |
| static LockHelper* pLock = NULL; |
| if( pLock == NULL ) |
| { |
| ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() ); |
| if( pLock == NULL ) |
| { |
| static LockHelper aLock( pSolarMutex ); |
| pLock = &aLock; |
| } |
| } |
| return *pLock; |
| } |
| |
| /*-************************************************************************************************************//** |
| @short return a reference to shared mutex member |
| @descr Sometimes we need a osl-mutex for sharing with our uno helper ... |
| What can we do? |
| a) If we have an initialized "own mutex" ... we can use it! |
| b) Otherwise we must use a different mutex member :-( |
| I HOPE IT WORKS! |
| |
| @seealso - |
| |
| @param - |
| @return A reference to a shared mutex. |
| |
| @onerror No error should occur. |
| *//*-*************************************************************************************************************/ |
| ::osl::Mutex& LockHelper::getShareableOslMutex() |
| { |
| if( m_pShareableOslMutex == NULL ) |
| { |
| ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() ); |
| if( m_pShareableOslMutex == NULL ) |
| { |
| switch( m_eLockType ) |
| { |
| case E_OWNMUTEX : { |
| m_pShareableOslMutex = m_pOwnMutex; |
| } |
| break; |
| default : { |
| m_pShareableOslMutex = new ::osl::Mutex; |
| } |
| break; |
| } |
| } |
| } |
| return *m_pShareableOslMutex; |
| } |
| |
| /*-************************************************************************************************************//** |
| @short search for right lock type, which should be used by an instance of this struct |
| @descr We must initialize our member "m_eLockType". This value specify handling of locking. |
| How we can do that? We search for an environment variable. We do it only for one time .... |
| because the environment is fix. So we safe this value and use it for all further requests. |
| If no variable could be found - we use a fallback! |
| |
| @attention We have numbered all our enum values for ELockType. So we can use it as value of searched |
| environment variable too! |
| |
| @seealso enum ELockType |
| @seealso environment LOCKTYPE |
| |
| @param - |
| @return A reference to a created and right initialized lock type! |
| |
| @onerror We use a fallback! |
| *//*-*************************************************************************************************************/ |
| ELockType& LockHelper::implts_getLockType() |
| { |
| // Initialize static "member" only for one time! |
| // Algorithm: |
| // a) Start with an invalid variable (NULL pointer) |
| // b) If these method first called (value not already exist!) ... |
| // c) ... we must create a new one. Protect follow code with the global mutex - |
| // (It must be - we create a static variable!) |
| // d) Check pointer again - because ... another instance of our class could be faster then these one! |
| // e) Create the new static variable, get value from the environment and set it |
| // f) Return new created or already existing static variable. |
| static ELockType* pType = NULL; |
| if( pType == NULL ) |
| { |
| ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() ); |
| if( pType == NULL ) |
| { |
| static ELockType eType = FALLBACK_LOCKTYPE; |
| |
| ::vos::OStartupInfo aEnvironment; |
| ::rtl::OUString sValue ; |
| if( aEnvironment.getEnvironment( ENVVAR_LOCKTYPE, sValue ) == ::vos::OStartupInfo::E_None ) |
| { |
| eType = (ELockType)(sValue.toInt32()); |
| } |
| |
| LOG_LOCKTYPE( FALLBACK_LOCKTYPE, eType ) |
| |
| pType = &eType; |
| } |
| } |
| return *pType; |
| } |
| |
| } // namespace framework |