From 8f7ec64899c54dcee6caa0307510cc4003ba7bdd Mon Sep 17 00:00:00 2001 From: James Cook Date: Mon, 27 Jul 2009 17:56:26 +0000 Subject: Merged skinning-17 into viewer-2 for bug fixes. Commented out new IM window for now, not complete. Merging revisions 127913-128319 of svn+ssh://svn.lindenlab.com/svn/linden/branches/skinning/skinning-17 into D:\viewer-2.0.0-3, respecting ancestry --- indra/llui/llhandle.h | 171 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 171 insertions(+) create mode 100644 indra/llui/llhandle.h (limited to 'indra/llui/llhandle.h') diff --git a/indra/llui/llhandle.h b/indra/llui/llhandle.h new file mode 100644 index 0000000000..10a7fd4544 --- /dev/null +++ b/indra/llui/llhandle.h @@ -0,0 +1,171 @@ +/** +* @file llhandle.h +* @brief "Handle" to an object (usually a floater) whose lifetime you don't +* control. +* +* $LicenseInfo:firstyear=2001&license=viewergpl$ +* +* Copyright (c) 2001-2009, Linden Research, Inc. +* +* 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 +* +* 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 +* +* 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. +* +* ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO +* WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY, +* COMPLETENESS OR PERFORMANCE. +* $/LicenseInfo$ +*/ +#ifndef LLHANDLE_H +#define LLHANDLE_H + +#include "llpointer.h" + +template +class LLTombStone : public LLRefCount +{ +public: + LLTombStone(T* target = NULL) : mTarget(target) {} + + void setTarget(T* target) { mTarget = target; } + T* getTarget() const { return mTarget; } +private: + T* mTarget; +}; + +// LLHandles are used to refer to objects whose lifetime you do not control or influence. +// Calling get() on a handle will return a pointer to the referenced object or NULL, +// if the object no longer exists. Note that during the lifetime of the returned pointer, +// you are assuming that the object will not be deleted by any action you perform, +// or any other thread, as normal when using pointers, so avoid using that pointer outside of +// the local code block. +// +// https://wiki.lindenlab.com/mediawiki/index.php?title=LLHandle&oldid=79669 + +template +class LLHandle +{ +public: + LLHandle() : mTombStone(sDefaultTombStone) {} + const LLHandle& operator =(const LLHandle& other) + { + mTombStone = other.mTombStone; + return *this; + } + + bool isDead() const + { + return mTombStone->getTarget() == NULL; + } + + void markDead() + { + mTombStone = sDefaultTombStone; + } + + T* get() const + { + return mTombStone->getTarget(); + } + + friend bool operator== (const LLHandle& lhs, const LLHandle& rhs) + { + return lhs.mTombStone == rhs.mTombStone; + } + friend bool operator!= (const LLHandle& lhs, const LLHandle& rhs) + { + return !(lhs == rhs); + } + friend bool operator< (const LLHandle& lhs, const LLHandle& rhs) + { + return lhs.mTombStone < rhs.mTombStone; + } + friend bool operator> (const LLHandle& lhs, const LLHandle& rhs) + { + return lhs.mTombStone > rhs.mTombStone; + } +protected: + +protected: + LLPointer > mTombStone; + +private: + static LLPointer > sDefaultTombStone; +}; + +// initialize static "empty" tombstone pointer +template LLPointer > LLHandle::sDefaultTombStone = new LLTombStone(); + + +template +class LLRootHandle : public LLHandle +{ +public: + LLRootHandle(T* object) { bind(object); } + LLRootHandle() {}; + ~LLRootHandle() { unbind(); } + + // this is redundant, since a LLRootHandle *is* an LLHandle + LLHandle getHandle() { return LLHandle(*this); } + + void bind(T* object) + { + // unbind existing tombstone + if (LLHandle::mTombStone.notNull()) + { + if (LLHandle::mTombStone->getTarget() == object) return; + LLHandle::mTombStone->setTarget(NULL); + } + // tombstone reference counted, so no paired delete + LLHandle::mTombStone = new LLTombStone(object); + } + + void unbind() + { + LLHandle::mTombStone->setTarget(NULL); + } + + //don't allow copying of root handles, since there should only be one +private: + LLRootHandle(const LLRootHandle& other) {}; +}; + +// Use this as a mixin for simple classes that need handles and when you don't +// want handles at multiple points of the inheritance hierarchy +template +class LLHandleProvider +{ +protected: + typedef LLHandle handle_type_t; + LLHandleProvider() + { + // provided here to enforce T deriving from LLHandleProvider + } + + LLHandle getHandle() + { + // perform lazy binding to avoid small tombstone allocations for handle + // providers whose handles are never referenced + mHandle.bind(static_cast(this)); + return mHandle; + } + +private: + LLRootHandle mHandle; +}; + +#endif -- cgit v1.2.3