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Diffstat (limited to 'indra/llcommon/llinstancetracker.h')
| -rwxr-xr-x[-rw-r--r--] | indra/llcommon/llinstancetracker.h | 377 |
1 files changed, 266 insertions, 111 deletions
diff --git a/indra/llcommon/llinstancetracker.h b/indra/llcommon/llinstancetracker.h index 9df7998273..9783644e66 100644..100755 --- a/indra/llcommon/llinstancetracker.h +++ b/indra/llcommon/llinstancetracker.h @@ -3,31 +3,25 @@ * @brief LLInstanceTracker is a mixin class that automatically tracks object * instances with or without an associated key * - * $LicenseInfo:firstyear=2000&license=viewergpl$ - * - * Copyright (c) 2000-2009, Linden Research, Inc. - * + * $LicenseInfo:firstyear=2000&license=viewerlgpl$ * Second Life Viewer Source Code - * The source code in this file ("Source Code") is provided by Linden Lab - * to you under the terms of the GNU General Public License, version 2.0 - * ("GPL"), unless you have obtained a separate licensing agreement - * ("Other License"), formally executed by you and Linden Lab. Terms of - * the GPL can be found in doc/GPL-license.txt in this distribution, or - * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2 + * Copyright (C) 2010, Linden Research, Inc. * - * There are special exceptions to the terms and conditions of the GPL as - * it is applied to this Source Code. View the full text of the exception - * in the file doc/FLOSS-exception.txt in this software distribution, or - * online at - * http://secondlifegrid.net/programs/open_source/licensing/flossexception + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License only. * - * By copying, modifying or distributing this software, you acknowledge - * that you have read and understood your obligations described above, - * and agree to abide by those obligations. + * 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. * - * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO - * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY, - * COMPLETENESS OR PERFORMANCE. + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA * $/LicenseInfo$ */ @@ -35,162 +29,323 @@ #define LL_LLINSTANCETRACKER_H #include <map> +#include <typeinfo> -#include "string_table.h" -#include <boost/utility.hpp> -#include <boost/function.hpp> -#include <boost/bind.hpp> +#include "llstringtable.h" #include <boost/iterator/transform_iterator.hpp> #include <boost/iterator/indirect_iterator.hpp> +/** + * Base class manages "class-static" data that must actually have singleton + * semantics: one instance per process, rather than one instance per module as + * sometimes happens with data simply declared static. + */ +class LL_COMMON_API LLInstanceTrackerBase +{ +protected: + /// It's not essential to derive your STATICDATA (for use with + /// getStatic()) from StaticBase; it's just that both known + /// implementations do. + struct StaticBase + { + StaticBase(): + sIterationNestDepth(0) + {} + + void incrementDepth(); + void decrementDepth(); + U32 getDepth(); + private: + U32 sIterationNestDepth; + }; +}; + +LL_COMMON_API void assert_main_thread(); + +enum EInstanceTrackerAllowKeyCollisions +{ + LLInstanceTrackerErrorOnCollision, + LLInstanceTrackerReplaceOnCollision +}; + /// This mix-in class adds support for tracking all instances of the specified class parameter T /// The (optional) key associates a value of type KEY with a given instance of T, for quick lookup /// If KEY is not provided, then instances are stored in a simple set -/// @NOTE: see explicit specialization below for default KEY==T* case -template<typename T, typename KEY = T*> -class LLInstanceTracker : boost::noncopyable +/// @NOTE: see explicit specialization below for default KEY==void case +/// @NOTE: this class is not thread-safe unless used as read-only +template<typename T, typename KEY = void, EInstanceTrackerAllowKeyCollisions KEY_COLLISION_BEHAVIOR = LLInstanceTrackerErrorOnCollision> +class LLInstanceTracker : public LLInstanceTrackerBase { - typedef typename std::map<KEY, T*> InstanceMap; - typedef boost::function<const KEY&(typename InstanceMap::value_type&)> KeyGetter; - typedef boost::function<T*(typename InstanceMap::value_type&)> InstancePtrGetter; + typedef LLInstanceTracker<T, KEY> self_t; + typedef typename std::multimap<KEY, T*> InstanceMap; + struct StaticData: public StaticBase + { + InstanceMap sMap; + }; + static StaticData& getStatic() { static StaticData sData; return sData;} + static InstanceMap& getMap_() { return getStatic().sMap; } + public: - /// Dereferencing key_iter gives you a const KEY& - typedef boost::transform_iterator<KeyGetter, typename InstanceMap::iterator> key_iter; - /// Dereferencing instance_iter gives you a T& - typedef boost::indirect_iterator< boost::transform_iterator<InstancePtrGetter, typename InstanceMap::iterator> > instance_iter; + class instance_iter : public boost::iterator_facade<instance_iter, T, boost::forward_traversal_tag> + { + public: + typedef boost::iterator_facade<instance_iter, T, boost::forward_traversal_tag> super_t; + + instance_iter(const typename InstanceMap::iterator& it) + : mIterator(it) + { + getStatic().incrementDepth(); + } + + ~instance_iter() + { + getStatic().decrementDepth(); + } + + + private: + friend class boost::iterator_core_access; + + void increment() { mIterator++; } + bool equal(instance_iter const& other) const + { + return mIterator == other.mIterator; + } + + T& dereference() const + { + return *(mIterator->second); + } + + typename InstanceMap::iterator mIterator; + }; + + class key_iter : public boost::iterator_facade<key_iter, KEY, boost::forward_traversal_tag> + { + public: + typedef boost::iterator_facade<key_iter, KEY, boost::forward_traversal_tag> super_t; + + key_iter(typename InstanceMap::iterator it) + : mIterator(it) + { + getStatic().incrementDepth(); + } + + key_iter(const key_iter& other) + : mIterator(other.mIterator) + { + getStatic().incrementDepth(); + } + + ~key_iter() + { + getStatic().decrementDepth(); + } + + + private: + friend class boost::iterator_core_access; + + void increment() { mIterator++; } + bool equal(key_iter const& other) const + { + return mIterator == other.mIterator; + } + + KEY& dereference() const + { + return const_cast<KEY&>(mIterator->first); + } + + typename InstanceMap::iterator mIterator; + }; static T* getInstance(const KEY& k) { - typename InstanceMap::const_iterator found = getMap_().find(k); - return (found == getMap_().end()) ? NULL : found->second; + const InstanceMap& map(getMap_()); + typename InstanceMap::const_iterator found = map.find(k); + return (found == map.end()) ? NULL : found->second; } - static key_iter beginKeys() - { - return boost::make_transform_iterator(getMap_().begin(), - boost::bind(&InstanceMap::value_type::first, _1)); + static instance_iter beginInstances() + { + return instance_iter(getMap_().begin()); } - static key_iter endKeys() + + static instance_iter endInstances() { - return boost::make_transform_iterator(getMap_().end(), - boost::bind(&InstanceMap::value_type::first, _1)); + return instance_iter(getMap_().end()); + } + + static S32 instanceCount() + { + return getMap_().size(); } - static instance_iter beginInstances() + + static key_iter beginKeys() { - return instance_iter(boost::make_transform_iterator(getMap_().begin(), - boost::bind(&InstanceMap::value_type::second, _1))); + return key_iter(getMap_().begin()); } - static instance_iter endInstances() + static key_iter endKeys() { - return instance_iter(boost::make_transform_iterator(getMap_().end(), - boost::bind(&InstanceMap::value_type::second, _1))); + return key_iter(getMap_().end()); } - static S32 instanceCount() { return getMap_().size(); } + protected: - LLInstanceTracker(KEY key) { add_(key); } - virtual ~LLInstanceTracker() { remove_(); } + LLInstanceTracker(const KEY& key) + { + // make sure static data outlives all instances + getStatic(); + add_(key); + } + virtual ~LLInstanceTracker() + { + // it's unsafe to delete instances of this type while all instances are being iterated over. + llassert_always(getStatic().getDepth() == 0); + remove_(); + } virtual void setKey(KEY key) { remove_(); add_(key); } - virtual const KEY& getKey() const { return mKey; } + virtual const KEY& getKey() const { return mInstanceKey; } private: - void add_(KEY key) + LLInstanceTracker( const LLInstanceTracker& ); + const LLInstanceTracker& operator=( const LLInstanceTracker& ); + + void add_(const KEY& key) { - mKey = key; - getMap_()[key] = static_cast<T*>(this); + mInstanceKey = key; + InstanceMap& map = getMap_(); + typename InstanceMap::iterator insertion_point_it = map.lower_bound(key); + if (insertion_point_it != map.end() + && insertion_point_it->first == key) + { // found existing entry with that key + switch(KEY_COLLISION_BEHAVIOR) + { + case LLInstanceTrackerErrorOnCollision: + { + // use assert here instead of LL_ERRS(), otherwise the error will be ignored since this call is made during global object initialization + llassert_always_msg(false, "Instance with this same key already exists!"); + break; + } + case LLInstanceTrackerReplaceOnCollision: + { + // replace pointer, but leave key (should have compared equal anyway) + insertion_point_it->second = static_cast<T*>(this); + break; + } + default: + break; + } + } + else + { // new key + map.insert(insertion_point_it, std::make_pair(key, static_cast<T*>(this))); + } } void remove_() { - getMap_().erase(mKey); + InstanceMap& map = getMap_(); + typename InstanceMap::iterator iter = map.find(mInstanceKey); + if (iter != map.end()) + { + map.erase(iter); + } } - static InstanceMap& getMap_() - { - if (! sInstances) - { - sInstances = new InstanceMap; - } - return *sInstances; - } - private: - - KEY mKey; - static InstanceMap* sInstances; + KEY mInstanceKey; }; -/// explicit specialization for default case where KEY is T* +/// explicit specialization for default case where KEY is void /// use a simple std::set<T*> -template<typename T> -class LLInstanceTracker<T, T*> +template<typename T, EInstanceTrackerAllowKeyCollisions KEY_COLLISION_BEHAVIOR> +class LLInstanceTracker<T, void, KEY_COLLISION_BEHAVIOR> : public LLInstanceTrackerBase { + typedef LLInstanceTracker<T, void> self_t; typedef typename std::set<T*> InstanceSet; + struct StaticData: public StaticBase + { + InstanceSet sSet; + }; + static StaticData& getStatic() { static StaticData sData; return sData; } + static InstanceSet& getSet_() { return getStatic().sSet; } + public: - /// Dereferencing key_iter gives you a T* (since T* is the key) - typedef typename InstanceSet::iterator key_iter; - /// Dereferencing instance_iter gives you a T& - typedef boost::indirect_iterator<key_iter> instance_iter; - /// for completeness of analogy with the generic implementation - static T* getInstance(T* k) { return k; } + /** + * Does a particular instance still exist? Of course, if you already have + * a T* in hand, you need not call getInstance() to @em locate the + * instance -- unlike the case where getInstance() accepts some kind of + * key. Nonetheless this method is still useful to @em validate a + * particular T*, since each instance's destructor removes itself from the + * underlying set. + */ + static T* getInstance(T* k) + { + const InstanceSet& set(getSet_()); + typename InstanceSet::const_iterator found = set.find(k); + return (found == set.end())? NULL : *found; + } static S32 instanceCount() { return getSet_().size(); } - // Instantiate this to get access to iterators for this type. It's a 'guard' in the sense - // that it treats deletes of this type as errors as long as there is an instance of - // this class alive in scope somewhere (i.e. deleting while iterating is bad). - class LLInstanceTrackerScopedGuard + class instance_iter : public boost::iterator_facade<instance_iter, T, boost::forward_traversal_tag> { public: - LLInstanceTrackerScopedGuard() + instance_iter(const typename InstanceSet::iterator& it) + : mIterator(it) { - ++sIterationNestDepth; + getStatic().incrementDepth(); } - ~LLInstanceTrackerScopedGuard() + instance_iter(const instance_iter& other) + : mIterator(other.mIterator) { - --sIterationNestDepth; + getStatic().incrementDepth(); } - static instance_iter beginInstances() { return instance_iter(getSet_().begin()); } - static instance_iter endInstances() { return instance_iter(getSet_().end()); } - static key_iter beginKeys() { return getSet_().begin(); } - static key_iter endKeys() { return getSet_().end(); } + ~instance_iter() + { + getStatic().decrementDepth(); + } + + private: + friend class boost::iterator_core_access; + + void increment() { mIterator++; } + bool equal(instance_iter const& other) const + { + return mIterator == other.mIterator; + } + + T& dereference() const + { + return **mIterator; + } + + typename InstanceSet::iterator mIterator; }; + static instance_iter beginInstances() { return instance_iter(getSet_().begin()); } + static instance_iter endInstances() { return instance_iter(getSet_().end()); } + protected: LLInstanceTracker() { - // it's safe but unpredictable to create instances of this type while all instances are being iterated over. I hate unpredictable. This assert will probably be turned on early in the next development cycle. - //llassert(sIterationNestDepth == 0); + // make sure static data outlives all instances + getStatic(); getSet_().insert(static_cast<T*>(this)); } virtual ~LLInstanceTracker() { // it's unsafe to delete instances of this type while all instances are being iterated over. - llassert(sIterationNestDepth == 0); + llassert_always(getStatic().getDepth() == 0); getSet_().erase(static_cast<T*>(this)); } LLInstanceTracker(const LLInstanceTracker& other) { - //llassert(sIterationNestDepth == 0); getSet_().insert(static_cast<T*>(this)); } - - static InstanceSet& getSet_() - { - if (! sInstances) - { - sInstances = new InstanceSet; - } - return *sInstances; - } - - static InstanceSet* sInstances; - static S32 sIterationNestDepth; }; -template <typename T, typename KEY> typename LLInstanceTracker<T, KEY>::InstanceMap* LLInstanceTracker<T, KEY>::sInstances = NULL; -template <typename T> typename LLInstanceTracker<T, T*>::InstanceSet* LLInstanceTracker<T, T*>::sInstances = NULL; -template <typename T> S32 LLInstanceTracker<T, T*>::sIterationNestDepth = 0; - #endif |