#89253# ReadWriteMutex/ReadWriteGuard for more than one I18N wrapper
This commit is contained in:
Eike Rathke
parent
253c0cc293
commit
738731209b
2 changed files with 307 additions and 0 deletions
149
unotools/inc/unotools/readwritemutexguard.hxx
Normal file
149
unotools/inc/unotools/readwritemutexguard.hxx
Normal file
|
|
@ -0,0 +1,149 @@
|
|||
/*************************************************************************
|
||||
*
|
||||
* $RCSfile: readwritemutexguard.hxx,v $
|
||||
*
|
||||
* $Revision: 1.1 $
|
||||
*
|
||||
* last change: $ $
|
||||
*
|
||||
* The Contents of this file are made available subject to the terms of
|
||||
* either of the following licenses
|
||||
*
|
||||
* - GNU Lesser General Public License Version 2.1
|
||||
* - Sun Industry Standards Source License Version 1.1
|
||||
*
|
||||
* Sun Microsystems Inc., October, 2000
|
||||
*
|
||||
* GNU Lesser General Public License Version 2.1
|
||||
* =============================================
|
||||
* Copyright 2000 by Sun Microsystems, Inc.
|
||||
* 901 San Antonio Road, Palo Alto, CA 94303, USA
|
||||
*
|
||||
* This library is free software; you can redistribute it and/or
|
||||
* modify it under the terms of the GNU Lesser General Public
|
||||
* License version 2.1, as published by the Free Software Foundation.
|
||||
*
|
||||
* This library is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser General Public
|
||||
* License along with this library; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
||||
* MA 02111-1307 USA
|
||||
*
|
||||
*
|
||||
* Sun Industry Standards Source License Version 1.1
|
||||
* =================================================
|
||||
* The contents of this file are subject to the Sun Industry Standards
|
||||
* Source License Version 1.1 (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.openoffice.org/license.html.
|
||||
*
|
||||
* Software provided under this License is provided on an "AS IS" basis,
|
||||
* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
|
||||
* WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
|
||||
* MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
|
||||
* See the License for the specific provisions governing your rights and
|
||||
* obligations concerning the Software.
|
||||
*
|
||||
* The Initial Developer of the Original Code is: Sun Microsystems, Inc.
|
||||
*
|
||||
* Copyright: 2000 by Sun Microsystems, Inc.
|
||||
*
|
||||
* All Rights Reserved.
|
||||
*
|
||||
* Contributor(s): _______________________________________
|
||||
*
|
||||
*
|
||||
************************************************************************/
|
||||
|
||||
#ifndef INCLUDED_UNOTOOLS_READWRITEMUTEXGUARD_HXX
|
||||
#define INCLUDED_UNOTOOLS_READWRITEMUTEXGUARD_HXX
|
||||
|
||||
#ifndef _OSL_MUTEX_HXX_
|
||||
#include <osl/mutex.hxx>
|
||||
#endif
|
||||
|
||||
namespace utl {
|
||||
|
||||
class ReadWriteGuard;
|
||||
class ReadWriteMutex
|
||||
{
|
||||
friend class ReadWriteGuard;
|
||||
|
||||
sal_uInt32 nReadCount;
|
||||
sal_uInt32 nBlockCriticalCount;
|
||||
::osl::Mutex* pMutex;
|
||||
::osl::Mutex* pWriteMutex;
|
||||
|
||||
public:
|
||||
ReadWriteMutex()
|
||||
: nReadCount(0)
|
||||
, nBlockCriticalCount(0)
|
||||
, pMutex( new ::osl::Mutex )
|
||||
, pWriteMutex( new ::osl::Mutex )
|
||||
{}
|
||||
~ReadWriteMutex()
|
||||
{
|
||||
delete pMutex;
|
||||
delete pWriteMutex;
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
namespace ReadWriteGuardMode {
|
||||
const sal_Int32 nWrite = 0x01;
|
||||
const sal_Int32 nCriticalChange = 0x02 | nWrite;
|
||||
const sal_Int32 nBlockCritical = 0x04; // only a block, not a read, exclusive flag!
|
||||
}
|
||||
|
||||
/** Enable multiple threads to read simultaneously, but a write blocks all
|
||||
other reads and writes, and a read blocks any write.
|
||||
Used in I18N wrappers to be able to maintain a single instance of a wrapper
|
||||
for the standard Office locale.
|
||||
NEVER construct a writing guard if there is already a reading guard in the
|
||||
same context, the following will dead lock EVEN IN THE SAME THREAD!
|
||||
void foo()
|
||||
{
|
||||
ReadWriteGuard aGuard1( aMutex );
|
||||
bar();
|
||||
}
|
||||
void bar()
|
||||
{
|
||||
// waits forever for aGuard1
|
||||
ReadWriteGuard aGuard2( aMutex, ReadWriteGuardMode::nWrite );
|
||||
}
|
||||
*/
|
||||
class ReadWriteGuard
|
||||
{
|
||||
ReadWriteMutex& rMutex;
|
||||
sal_Int32 nMode;
|
||||
public:
|
||||
ReadWriteGuard(
|
||||
ReadWriteMutex& rMutex,
|
||||
sal_Int32 nRequestMode = 0 // read only
|
||||
);
|
||||
~ReadWriteGuard();
|
||||
|
||||
/** Be careful with this, it does wait for ANY read to complete.
|
||||
The following will dead lock EVEN IN THE SAME THREAD!
|
||||
void foo()
|
||||
{
|
||||
ReadWriteGuard aGuard1( aMutex );
|
||||
bar();
|
||||
}
|
||||
void bar()
|
||||
{
|
||||
ReadWriteGuard aGuard2( aMutex );
|
||||
aGuard2.changeReadToWrite(); // waits forever for aGuard1
|
||||
}
|
||||
*/
|
||||
void changeReadToWrite();
|
||||
};
|
||||
|
||||
} // namespace utl
|
||||
|
||||
#endif // INCLUDED_UNOTOOLS_READWRITEMUTEXGUARD_HXX
|
||||
|
||||
158
unotools/source/i18n/readwritemutexguard.cxx
Normal file
158
unotools/source/i18n/readwritemutexguard.cxx
Normal file
|
|
@ -0,0 +1,158 @@
|
|||
/*************************************************************************
|
||||
*
|
||||
* $RCSfile: readwritemutexguard.cxx,v $
|
||||
*
|
||||
* $Revision: 1.1 $
|
||||
*
|
||||
* last change: $ $
|
||||
*
|
||||
* The Contents of this file are made available subject to the terms of
|
||||
* either of the following licenses
|
||||
*
|
||||
* - GNU Lesser General Public License Version 2.1
|
||||
* - Sun Industry Standards Source License Version 1.1
|
||||
*
|
||||
* Sun Microsystems Inc., October, 2000
|
||||
*
|
||||
* GNU Lesser General Public License Version 2.1
|
||||
* =============================================
|
||||
* Copyright 2000 by Sun Microsystems, Inc.
|
||||
* 901 San Antonio Road, Palo Alto, CA 94303, USA
|
||||
*
|
||||
* This library is free software; you can redistribute it and/or
|
||||
* modify it under the terms of the GNU Lesser General Public
|
||||
* License version 2.1, as published by the Free Software Foundation.
|
||||
*
|
||||
* This library is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser General Public
|
||||
* License along with this library; if not, write to the Free Software
|
||||
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
||||
* MA 02111-1307 USA
|
||||
*
|
||||
*
|
||||
* Sun Industry Standards Source License Version 1.1
|
||||
* =================================================
|
||||
* The contents of this file are subject to the Sun Industry Standards
|
||||
* Source License Version 1.1 (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.openoffice.org/license.html.
|
||||
*
|
||||
* Software provided under this License is provided on an "AS IS" basis,
|
||||
* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
|
||||
* WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
|
||||
* MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
|
||||
* See the License for the specific provisions governing your rights and
|
||||
* obligations concerning the Software.
|
||||
*
|
||||
* The Initial Developer of the Original Code is: Sun Microsystems, Inc.
|
||||
*
|
||||
* Copyright: 2000 by Sun Microsystems, Inc.
|
||||
*
|
||||
* All Rights Reserved.
|
||||
*
|
||||
* Contributor(s): _______________________________________
|
||||
*
|
||||
*
|
||||
************************************************************************/
|
||||
|
||||
#pragma hdrstop
|
||||
|
||||
#ifndef INCLUDED_UNOTOOLS_READWRITEMUTEXGUARD_HXX
|
||||
#include "unotools/readwritemutexguard.hxx"
|
||||
#endif
|
||||
#ifndef _TOOLS_DEBUG_HXX
|
||||
#include <tools/debug.hxx>
|
||||
#endif
|
||||
|
||||
|
||||
namespace utl {
|
||||
|
||||
ReadWriteGuard::ReadWriteGuard( ReadWriteMutex& rMutexP,
|
||||
sal_Int32 nRequestMode )
|
||||
: rMutex( rMutexP )
|
||||
{
|
||||
// don't do anything until a pending write completed (or another
|
||||
// ReadWriteGuard leaves the ctor phase)
|
||||
::osl::MutexGuard aGuard( rMutex.pWriteMutex );
|
||||
nMode = nRequestMode;
|
||||
if ( nMode & ReadWriteGuardMode::nWrite )
|
||||
{
|
||||
rMutex.pWriteMutex->acquire();
|
||||
// wait for any read to complete
|
||||
// TODO: set up a waiting thread instead of a loop
|
||||
sal_Bool bWait = sal_True;
|
||||
do
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
bWait = (rMutex.nReadCount != 0);
|
||||
if ( nMode & ReadWriteGuardMode::nCriticalChange )
|
||||
bWait |= (rMutex.nBlockCriticalCount != 0);
|
||||
rMutex.pMutex->release();
|
||||
} while ( bWait );
|
||||
}
|
||||
else if ( nMode & ReadWriteGuardMode::nBlockCritical )
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
++rMutex.nBlockCriticalCount;
|
||||
rMutex.pMutex->release();
|
||||
}
|
||||
else
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
++rMutex.nReadCount;
|
||||
rMutex.pMutex->release();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
ReadWriteGuard::~ReadWriteGuard()
|
||||
{
|
||||
if ( nMode & ReadWriteGuardMode::nWrite )
|
||||
rMutex.pWriteMutex->release();
|
||||
else if ( nMode & ReadWriteGuardMode::nBlockCritical )
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
--rMutex.nBlockCriticalCount;
|
||||
rMutex.pMutex->release();
|
||||
}
|
||||
else
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
--rMutex.nReadCount;
|
||||
rMutex.pMutex->release();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
void ReadWriteGuard::changeReadToWrite()
|
||||
{
|
||||
sal_Bool bOk = !(nMode & (ReadWriteGuardMode::nWrite | ReadWriteGuardMode::nBlockCritical));
|
||||
DBG_ASSERT( bOk, "ReadWriteGuard::changeReadToWrite: can't" );
|
||||
if ( bOk )
|
||||
{
|
||||
// MUST release read before acquiring write mutex or dead lock would
|
||||
// occur if there was a write in another thread waiting for this read
|
||||
// to complete.
|
||||
rMutex.pMutex->acquire();
|
||||
--rMutex.nReadCount;
|
||||
rMutex.pMutex->release();
|
||||
|
||||
rMutex.pWriteMutex->acquire();
|
||||
nMode |= ReadWriteGuardMode::nWrite;
|
||||
// wait for any other read to complete
|
||||
// TODO: set up a waiting thread instead of a loop
|
||||
sal_Bool bWait = sal_True;
|
||||
do
|
||||
{
|
||||
rMutex.pMutex->acquire();
|
||||
bWait = (rMutex.nReadCount != 0);
|
||||
rMutex.pMutex->release();
|
||||
} while ( bWait );
|
||||
}
|
||||
}
|
||||
|
||||
} // namespace utl
|
||||
Loading…
Reference in a new issue