| /************************************************************** |
| * |
| * 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. |
| * |
| *************************************************************/ |
| |
| |
| |
| #ifndef __FRAMEWORK_THREADHELP_READGUARD_HXX_ |
| #define __FRAMEWORK_THREADHELP_READGUARD_HXX_ |
| |
| //_________________________________________________________________________________________________________________ |
| // my own includes |
| //_________________________________________________________________________________________________________________ |
| |
| #include <threadhelp/inoncopyable.h> |
| #include <threadhelp/irwlock.h> |
| |
| //#ifndef __FRAMEWORK_THREADHELP_THREADHELPBASE_HXX_ |
| //#include <threadhelp/threadhelpbase.hxx> |
| //#endif |
| |
| //_________________________________________________________________________________________________________________ |
| // interface includes |
| //_________________________________________________________________________________________________________________ |
| |
| //_________________________________________________________________________________________________________________ |
| // other includes |
| //_________________________________________________________________________________________________________________ |
| #include <sal/types.h> |
| |
| //_________________________________________________________________________________________________________________ |
| // namespace |
| //_________________________________________________________________________________________________________________ |
| |
| namespace framework{ |
| |
| //_________________________________________________________________________________________________________________ |
| // const |
| //_________________________________________________________________________________________________________________ |
| |
| //_________________________________________________________________________________________________________________ |
| // declarations |
| //_________________________________________________________________________________________________________________ |
| |
| /*-************************************************************************************************************//** |
| @short implement a guard to set read locks |
| @descr This guard should be used to set a lock for reading object internal member. |
| Nobody can control it but don't use member after successfuly locking for writing! |
| We never need a own mutex to safe our internal member access - because |
| a guard is used as function-local member only. There exists no multithreaded access to it really ... |
| |
| @attention a) To prevent us against wrong using, the default ctor, copy ctor and the =operator are maked private! |
| b) Use interface "IRWLock" of set LockHelper only - because we must support a finer granularity of locking. |
| Interface "IMutex" should be used by easier guard implementations ... like "ResetableGuard"! |
| |
| @implements - |
| @base INonCopyable |
| |
| @devstatus ready to use |
| *//*-*************************************************************************************************************/ |
| class ReadGuard : private INonCopyable |
| { |
| //------------------------------------------------------------------------------------------------------------- |
| // public methods |
| //------------------------------------------------------------------------------------------------------------- |
| public: |
| |
| /*-****************************************************************************************************//** |
| @short ctor |
| @descr These ctors initialize the guard with a reference to used lock member of object to protect. |
| Null isn't allowed as value! |
| |
| @seealso - |
| |
| @param "pLock" ,reference to used lock member of object to protect |
| @param "rLock" ,reference to used lock member of object to protect |
| @return - |
| |
| @onerror - |
| *//*-*****************************************************************************************************/ |
| inline ReadGuard( IRWLock* pLock ) |
| : m_pLock ( pLock ) |
| , m_bLocked ( sal_False ) |
| { |
| lock(); |
| } |
| |
| //********************************************************************************************************* |
| inline ReadGuard( IRWLock& rLock ) |
| : m_pLock ( &rLock ) |
| , m_bLocked ( sal_False ) |
| { |
| lock(); |
| } |
| |
| /*-****************************************************************************************************//** |
| @short dtor |
| @descr We unlock the used lock member automatically if user forgets it. |
| |
| @seealso - |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*****************************************************************************************************/ |
| inline ~ReadGuard() |
| { |
| unlock(); |
| } |
| |
| /*-****************************************************************************************************//** |
| @short set read lock |
| @descr Call this method to set the read lock. The call will block till all current threads are synchronized! |
| |
| @seealso method unlock() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*****************************************************************************************************/ |
| inline void lock() |
| { |
| if( m_bLocked == sal_False ) |
| { |
| m_pLock->acquireReadAccess(); |
| m_bLocked = sal_True; |
| } |
| } |
| |
| /*-****************************************************************************************************//** |
| @short unset read lock |
| @descr Call this method to unlock the rw-lock temp.! |
| Normaly we do it at dtor automatically for you ... |
| |
| @seealso method lock() |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*****************************************************************************************************/ |
| inline void unlock() |
| { |
| if( m_bLocked == sal_True ) |
| { |
| m_pLock->releaseReadAccess(); |
| m_bLocked = sal_False; |
| } |
| } |
| |
| //------------------------------------------------------------------------------------------------------------- |
| // private methods |
| //------------------------------------------------------------------------------------------------------------- |
| private: |
| |
| /*-****************************************************************************************************//** |
| @short disable using of these functions! |
| @descr It's not allowed to use this methods. Different problems can occur otherwise. |
| Thats why we disable it by make it private. |
| |
| @seealso other ctor |
| |
| @param - |
| @return - |
| |
| @onerror - |
| *//*-*****************************************************************************************************/ |
| ReadGuard(); |
| |
| //------------------------------------------------------------------------------------------------------------- |
| // private member |
| //------------------------------------------------------------------------------------------------------------- |
| private: |
| |
| IRWLock* m_pLock ; /// reference to lock-member of protected object |
| sal_Bool m_bLocked ; /// protection against multiple lock calls without unlock! |
| |
| }; // class ReadGuard |
| |
| } // namespace framework |
| |
| #endif // #ifndef __FRAMEWORK_THREADHELP_READGUARD_HXX_ |