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author | tpearson <tpearson@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2010-01-05 00:01:18 +0000 |
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committer | tpearson <tpearson@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2010-01-05 00:01:18 +0000 |
commit | 42995d7bf396933ee60c5f89c354ea89cf13df0d (patch) | |
tree | cfdcea0ac57420e7baf570bfe435e107bb842541 /flow/cache.cc | |
download | arts-42995d7bf396933ee60c5f89c354ea89cf13df0d.tar.gz arts-42995d7bf396933ee60c5f89c354ea89cf13df0d.zip |
Copy of aRts for Trinity modifications
git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/dependencies/arts@1070145 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'flow/cache.cc')
-rw-r--r-- | flow/cache.cc | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/flow/cache.cc b/flow/cache.cc new file mode 100644 index 0000000..0c7cfcc --- /dev/null +++ b/flow/cache.cc @@ -0,0 +1,274 @@ + /* + + Copyright (C) 2000 Stefan Westerfeld + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public License + along with this library; see the file COPYING.LIB. If not, write to + the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. + + */ + +#include "cache.h" +#include "debug.h" +#include "iomanager.h" +#include "dispatcher.h" +#include <iostream> +#include <assert.h> + +using namespace std; +using namespace Arts; + +bool CachedObject::isValid() +{ + return true; +} + +void CachedObject::setKey(string key) +{ + _object_key = key; +} + +string CachedObject::getKey() +{ + return _object_key; +} + +void CachedObject::decRef() +{ + _ref_cnt--; + time(&_lastAccess); +} + +void CachedObject::incRef() +{ + _ref_cnt++; +} + +int CachedObject::refCnt() +{ + return _ref_cnt; +} + +time_t CachedObject::lastAccess() +{ + return(_lastAccess); +} + +CachedObject::CachedObject(Cache *cache) +{ + _ref_cnt = 1; + cache->add(this); +} + +CachedObject::~CachedObject() +{ + assert(_ref_cnt == 0); +} + +//------------------------- Cache implementation --------------------------- +long Cache::memused = 0; + +CachedObject *Cache::get(string key) +{ + list<CachedObject *>::iterator i; + + for(i=objects.begin();i != objects.end(); i++) + { + if((*i)->getKey() == key && (*i)->isValid()) + { + (*i)->incRef(); + return(*i); + } + } + return 0; +} + +void Cache::add(CachedObject *object) +{ + objects.push_back(object); +} + +long Cache::cleanUp(long cacheLimit) +{ + time_t lastAccess; + + list<CachedObject *>::iterator i; + long memory = 0; + + // delete all invalid unused entries (invalid entries that are still + // in use, e.g. cached wav files which have changed on disk but are + // still played can't be deleted!) + + for(i=objects.begin();i != objects.end(); i++) + { + CachedObject *co = (*i); + + if(co->refCnt() == 0 && !co->isValid()) + { + objects.remove(co); + delete co; + i = objects.begin(); + } + } + + for(i=objects.begin();i != objects.end(); i++) + { + memory += (*i)->memoryUsage(); + } + + bool freeok = true; + while(memory > cacheLimit && freeok) + { + CachedObject *freeme; + + freeok = false; + + // only start freeing objects which have not been accessed + // in the last 5 seconds + + time(&lastAccess); + lastAccess -= 5; + + + for(i=objects.begin();!freeok && (i != objects.end()); i++) + { + CachedObject *co = (*i); + + assert(co->refCnt() >= 0); + if(co->refCnt() == 0 && (co->lastAccess() < lastAccess)) + { + lastAccess = co->lastAccess(); + freeme = co; + freeok = true; + } + else + { + //artsdebug("%d => %ld\n",co->refCnt(),co->lastAccess()); + } + } + + if(freeok) + { + memory -= freeme->memoryUsage(); + objects.remove(freeme); + delete(freeme); + } + else + { + //artsdebug("cache problem: memory overused, but nothing there to free\n"); + } + } + + memused = memory/1024; + return(memory); +} + +Cache *Cache::_instance = 0; + +Cache::Cache() +{ + assert(!_instance); + _instance = this; +} + +Cache::~Cache() +{ + list<CachedObject *>::iterator i; + for(i=objects.begin(); i != objects.end(); i++) + delete (*i); + objects.clear(); + + assert(_instance); + _instance = 0; +} + + +Cache *Cache::the() +{ + if(!_instance) _instance = new Cache(); + return _instance; +} + +void Cache::shutdown() +{ + if(_instance) + { + list<CachedObject *>::iterator i; + long rcnt = 0; + for(i=_instance->objects.begin(); i != _instance->objects.end(); i++) + rcnt += (*i)->refCnt(); + + if(rcnt == 0) + { + delete _instance; + _instance = 0; + } + else + { + arts_warning("cache shutdown while still active objects in cache"); + } + } +} + +namespace Arts { // internal helpers + +// periodic cache clean +class CacheClean : public TimeNotify { +public: + CacheClean(); + void notifyTime(); + virtual ~CacheClean(); +}; + +// cache startup & shutdown +class CacheStartup :public StartupClass +{ +public: + void startup(); + void shutdown(); +private: + CacheClean *cacheClean; +}; + +} + +CacheClean::CacheClean() +{ + Dispatcher::the()->ioManager()->addTimer(5000, this); +} + +void CacheClean::notifyTime() +{ + // TODO: make this configurable + Cache::the()->cleanUp(8192*1024); +} + +CacheClean::~CacheClean() +{ + Dispatcher::the()->ioManager()->removeTimer(this); +} + +void CacheStartup::startup() +{ + cacheClean = new CacheClean; +} + +void CacheStartup::shutdown() +{ + delete cacheClean; + Cache::shutdown(); +} + +static CacheStartup cacheStartup; |