diff options
author | Oz Linden <oz@lindenlab.com> | 2013-11-19 17:59:55 -0500 |
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committer | Oz Linden <oz@lindenlab.com> | 2013-11-19 17:59:55 -0500 |
commit | 0031e9a97be1bf6e9fe773c23506494d09ce91ae (patch) | |
tree | 220f195c82174b7cc8e94dceb2553e59fe5837a5 /indra/llcommon/llsingleton.h | |
parent | b7edc965bc77ab21e9a1e3f6b424299a50053529 (diff) | |
parent | ebc9bcbf69f7a519677a6522979a6bf6cbb04bb8 (diff) |
merge up to 3.6.10-release; some of the storm-68 changes lost
Diffstat (limited to 'indra/llcommon/llsingleton.h')
-rwxr-xr-x[-rw-r--r--] | indra/llcommon/llsingleton.h | 143 |
1 files changed, 60 insertions, 83 deletions
diff --git a/indra/llcommon/llsingleton.h b/indra/llcommon/llsingleton.h index 49d99f2cd0..40002313f1 100644..100755 --- a/indra/llcommon/llsingleton.h +++ b/indra/llcommon/llsingleton.h @@ -30,38 +30,6 @@ #include <typeinfo> #include <boost/noncopyable.hpp> -/// @brief A global registry of all singletons to prevent duplicate allocations -/// across shared library boundaries -class LL_COMMON_API LLSingletonRegistry { - private: - typedef std::map<std::string, void *> TypeMap; - static TypeMap * sSingletonMap; - - static void checkInit() - { - if(sSingletonMap == NULL) - { - sSingletonMap = new TypeMap(); - } - } - - public: - template<typename T> static void * & get() - { - std::string name(typeid(T).name()); - - checkInit(); - - // the first entry of the pair returned by insert will be either the existing - // iterator matching our key, or the newly inserted NULL initialized entry - // see "Insert element" in http://www.sgi.com/tech/stl/UniqueAssociativeContainer.html - TypeMap::iterator result = - sSingletonMap->insert(std::make_pair(name, (void*)NULL)).first; - - return result->second; - } -}; - // LLSingleton implements the getInstance() method part of the Singleton // pattern. It can't make the derived class constructors protected, though, so // you have to do that yourself. @@ -101,20 +69,23 @@ private: } EInitState; // stores pointer to singleton instance - // and tracks initialization state of singleton - struct SingletonInstanceData + struct SingletonLifetimeManager { - EInitState mInitState; - DERIVED_TYPE* mSingletonInstance; - - SingletonInstanceData() - : mSingletonInstance(NULL), - mInitState(UNINITIALIZED) - {} - - ~SingletonInstanceData() + SingletonLifetimeManager() + { + construct(); + } + + static void construct() { - if (mInitState != DELETED) + sData.mInitState = CONSTRUCTING; + sData.mInstance = new DERIVED_TYPE(); + sData.mInitState = INITIALIZING; + } + + ~SingletonLifetimeManager() + { + if (sData.mInitState != DELETED) { deleteSingleton(); } @@ -124,9 +95,8 @@ private: public: virtual ~LLSingleton() { - SingletonInstanceData& data = getData(); - data.mSingletonInstance = NULL; - data.mInitState = DELETED; + sData.mInstance = NULL; + sData.mInitState = DELETED; } /** @@ -151,50 +121,46 @@ public: */ static void deleteSingleton() { - delete getData().mSingletonInstance; - getData().mSingletonInstance = NULL; - getData().mInitState = DELETED; + delete sData.mInstance; + sData.mInstance = NULL; + sData.mInitState = DELETED; } - static SingletonInstanceData& getData() - { - // this is static to cache the lookup results - static void * & registry = LLSingletonRegistry::get<DERIVED_TYPE>(); - - // *TODO - look into making this threadsafe - if(NULL == registry) - { - static SingletonInstanceData data; - registry = &data; - } - - return *static_cast<SingletonInstanceData *>(registry); - } static DERIVED_TYPE* getInstance() { - SingletonInstanceData& data = getData(); + static SingletonLifetimeManager sLifeTimeMgr; - if (data.mInitState == CONSTRUCTING) + switch (sData.mInitState) { + case UNINITIALIZED: + // should never be uninitialized at this point + llassert(false); + return NULL; + case CONSTRUCTING: llerrs << "Tried to access singleton " << typeid(DERIVED_TYPE).name() << " from singleton constructor!" << llendl; - } - - if (data.mInitState == DELETED) - { + return NULL; + case INITIALIZING: + // go ahead and flag ourselves as initialized so we can be reentrant during initialization + sData.mInitState = INITIALIZED; + sData.mInstance->initSingleton(); + return sData.mInstance; + case INITIALIZED: + return sData.mInstance; + case DELETED: llwarns << "Trying to access deleted singleton " << typeid(DERIVED_TYPE).name() << " creating new instance" << llendl; + SingletonLifetimeManager::construct(); + sData.mInitState = INITIALIZED; + sData.mInstance->initSingleton(); + return sData.mInstance; } - - if (!data.mSingletonInstance) - { - data.mInitState = CONSTRUCTING; - data.mSingletonInstance = new DERIVED_TYPE(); - data.mInitState = INITIALIZING; - data.mSingletonInstance->initSingleton(); - data.mInitState = INITIALIZED; - } - - return data.mSingletonInstance; + + return NULL; + } + + static DERIVED_TYPE* getIfExists() + { + return sData.mInstance; } // Reference version of getInstance() @@ -208,18 +174,29 @@ public: // Use this to avoid accessing singletons before the can safely be constructed static bool instanceExists() { - return getData().mInitState == INITIALIZED; + return sData.mInitState == INITIALIZED; } // Has this singleton already been deleted? // Use this to avoid accessing singletons from a static object's destructor static bool destroyed() { - return getData().mInitState == DELETED; + return sData.mInitState == DELETED; } private: + virtual void initSingleton() {} + + struct SingletonData + { + EInitState mInitState; + DERIVED_TYPE* mInstance; + }; + static SingletonData sData; }; +template<typename T> +typename LLSingleton<T>::SingletonData LLSingleton<T>::sData; + #endif |