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Diffstat (limited to 'stoc/source/tdmanager/lrucache.hxx')
| -rw-r--r-- | stoc/source/tdmanager/lrucache.hxx | 242 |
1 files changed, 0 insertions, 242 deletions
diff --git a/stoc/source/tdmanager/lrucache.hxx b/stoc/source/tdmanager/lrucache.hxx deleted file mode 100644 index 0ab1712fb793..000000000000 --- a/stoc/source/tdmanager/lrucache.hxx +++ /dev/null @@ -1,242 +0,0 @@ -/* -*- 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 . - */ -#ifndef _LRU_CACHE_HXX_ -#define _LRU_CACHE_HXX_ - -// __CACHE_DIAGNOSE forces cache size to 4 and works only for OUString keys -// #define __CACHE_DIAGNOSE 1 - -#include <osl/mutex.hxx> -#include "rtl/ustring.hxx" -#include "sal/log.hxx" - -#include <boost/unordered_map.hpp> - - -/** Implementation of a least recently used (lru) cache. - <br> - @author Daniel Boelzle -*/ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -class LRU_Cache -{ - struct CacheEntry - { - t_Key aKey; - t_Val aVal; - CacheEntry * pPred; - CacheEntry * pSucc; - }; - typedef ::boost::unordered_map< t_Key, CacheEntry *, t_KeyHash, t_KeyEqual > t_Key2Element; - - mutable ::osl::Mutex _aCacheMutex; - sal_Int32 _nCachedElements; - t_Key2Element _aKey2Element; - - CacheEntry * _pBlock; - mutable CacheEntry * _pHead; - mutable CacheEntry * _pTail; - inline void toFront( CacheEntry * pEntry ) const; - -public: - /** Constructor: - <br> - @param nCachedElements number of elements to be cached; default param set to 128 - */ - inline LRU_Cache( sal_Int32 nCachedElements = 128 ); - /** Destructor: releases all cached elements and keys. - <br> - */ - inline ~LRU_Cache(); - - /** Retrieves a value from the cache. Returns default constructed value, - if none was found. - <br> - @param rKey a key - @return value - */ - inline t_Val getValue( t_Key const & rKey ) const; - /** Sets a value to be cached for given key. - <br> - @param rKey a key - @param rValue a value - */ - inline void setValue( t_Key const & rKey, t_Val const & rValue ); - /** Tests whether a value is cached for given key. - <br> - @param rKey a key - @return true, if value is cached - */ - inline sal_Bool hasValue( t_Key const & rKey ) const; - /** Clears the cache, thus releasing all cached elements and keys. - <br> - */ - inline void clear(); -}; -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::LRU_Cache( sal_Int32 nCachedElements ) -#ifdef __CACHE_DIAGNOSE - : _nCachedElements( 4 ) -#else - : _nCachedElements( nCachedElements ) -#endif - , _pBlock( 0 ) -{ - if (_nCachedElements > 0) - { - _pBlock = new CacheEntry[_nCachedElements]; - _pHead = _pBlock; - _pTail = _pBlock + _nCachedElements -1; - for ( sal_Int32 nPos = _nCachedElements; nPos--; ) - { - _pBlock[nPos].pPred = _pBlock + nPos -1; - _pBlock[nPos].pSucc = _pBlock + nPos +1; - } - } -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::~LRU_Cache() -{ - delete [] _pBlock; -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline void LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::toFront( - CacheEntry * pEntry ) const -{ - if (pEntry != _pHead) - { - // cut out element - if (pEntry == _pTail) - { - _pTail = pEntry->pPred; - } - else - { - pEntry->pSucc->pPred = pEntry->pPred; - pEntry->pPred->pSucc = pEntry->pSucc; - } - // push to front - _pHead->pPred = pEntry; - pEntry->pSucc = _pHead; - _pHead = pEntry; - } -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline sal_Bool LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::hasValue( - t_Key const & rKey ) const -{ - ::osl::MutexGuard aGuard( _aCacheMutex ); - typename t_Key2Element::const_iterator const iFind( _aKey2Element.find( rKey ) ); - return (iFind != _aKey2Element.end()); -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline t_Val LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::getValue( - t_Key const & rKey ) const -{ - ::osl::MutexGuard aGuard( _aCacheMutex ); - const typename t_Key2Element::const_iterator iFind( _aKey2Element.find( rKey ) ); - if (iFind != _aKey2Element.end()) - { - CacheEntry * pEntry = (*iFind).second; - toFront( pEntry ); -#ifdef __CACHE_DIAGNOSE - SAL_INFO("stoc.tdmanager", "> retrieved element \"" ); - SAL_INFO("stoc.tdmanager", "" << pEntry->aKey); - SAL_INFO("stoc.tdmanager", "\" from cache <" ); -#endif - return pEntry->aVal; - } - return t_Val(); -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline void LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::setValue( - t_Key const & rKey, t_Val const & rValue ) -{ - if (_nCachedElements > 0) - { - ::osl::MutexGuard aGuard( _aCacheMutex ); - typename t_Key2Element::const_iterator const iFind( _aKey2Element.find( rKey ) ); - - CacheEntry * pEntry; - if (iFind == _aKey2Element.end()) - { - pEntry = _pTail; // erase last element -#ifdef __CACHE_DIAGNOSE - if (pEntry->aKey.getLength()) - { - SAL_INFO("stoc.tdmanager", "> kicking element \"" ); - SAL_INFO("stoc.tdmanager", "" << pEntry->aKey); - SAL_INFO("stoc.tdmanager", "\" from cache <" ); - } -#endif - _aKey2Element.erase( pEntry->aKey ); - _aKey2Element[ pEntry->aKey = rKey ] = pEntry; - } - else - { - pEntry = (*iFind).second; -#ifdef __CACHE_DIAGNOSE - SAL_INFO("stoc.tdmanager", "> replacing element \"" ); - SAL_INFO("stoc.tdmanager", "" << pEntry->aKey); - SAL_INFO("stoc.tdmanager", "\" in cache <" ); -#endif - } - pEntry->aVal = rValue; - toFront( pEntry ); - } -} -//__________________________________________________________________________________________________ -template< class t_Key, class t_Val, class t_KeyHash, class t_KeyEqual > -inline void LRU_Cache< t_Key, t_Val, t_KeyHash, t_KeyEqual >::clear() -{ - ::osl::MutexGuard aGuard( _aCacheMutex ); - _aKey2Element.clear(); - for ( sal_Int32 nPos = _nCachedElements; nPos--; ) - { - _pBlock[nPos].aKey = t_Key(); - _pBlock[nPos].aVal = t_Val(); - } -#ifdef __CACHE_DIAGNOSE - SAL_INFO("stoc.tdmanager", "> cleared cache <" ); -#endif -} - -//================================================================================================== -struct FctHashOUString : public ::std::unary_function< OUString const &, size_t > -{ - size_t operator()( OUString const & rKey ) const - { return (size_t)rKey.hashCode(); } -}; - -/** Template instance for OUString keys, Any values.<br> -*/ -typedef LRU_Cache< OUString, ::com::sun::star::uno::Any, - FctHashOUString, ::std::equal_to< OUString > > - LRU_CacheAnyByOUString; - - -#endif - -/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |