Imported existing code

indra/llcommon/llpriqueuemap.h

@@ -0,0 +1,151 @@
+/** 
+ * @file llpriqueuemap.h
+ * @brief Priority queue implementation
+ *
+ * $LicenseInfo:firstyear=2003&license=viewergpl$
+ * 
+ * Copyright (c) 2003-2009, 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 LL_LLPRIQUEUEMAP_H
+#define LL_LLPRIQUEUEMAP_H
+
+#include <map>
+
+//
+// Priority queue, implemented under the hood as a
+// map.  Needs to be done this way because none of the
+// standard STL containers provide a representation
+// where it's easy to reprioritize.
+//
+
+template <class DATA>
+class LLPQMKey
+{
+public:
+	LLPQMKey(const F32 priority, DATA data) : mPriority(priority), mData(data)
+	{
+	}
+
+	bool operator<(const LLPQMKey &b) const
+	{
+		if (mPriority > b.mPriority)
+		{
+			return TRUE;
+		}
+		if (mPriority < b.mPriority)
+		{
+			return FALSE;
+		}
+		if (mData > b.mData)
+		{
+			return TRUE;
+		}
+		return FALSE;
+	}
+
+	F32 mPriority;
+	DATA mData;
+};
+
+template <class DATA_TYPE>
+class LLPriQueueMap
+{
+public:
+	typedef typename std::map<LLPQMKey<DATA_TYPE>, DATA_TYPE>::iterator pqm_iter;
+	typedef std::pair<LLPQMKey<DATA_TYPE>, DATA_TYPE> pqm_pair;
+	typedef void (*set_pri_fn)(DATA_TYPE &data, const F32 priority);
+	typedef F32 (*get_pri_fn)(DATA_TYPE &data);
+
+
+	LLPriQueueMap(set_pri_fn set_pri, get_pri_fn get_pri) : mSetPriority(set_pri), mGetPriority(get_pri)
+	{
+	}
+
+	void push(const F32 priority, DATA_TYPE data)
+	{
+#ifdef _DEBUG
+		pqm_iter iter = mMap.find(LLPQMKey<DATA_TYPE>(priority, data));
+		if (iter != mMap.end())
+		{
+			llerrs << "Pushing already existing data onto queue!" << llendl;
+		}
+#endif
+		mMap.insert(pqm_pair(LLPQMKey<DATA_TYPE>(priority, data), data));
+	}
+
+	BOOL pop(DATA_TYPE *datap)
+	{
+		pqm_iter iter;
+		iter = mMap.begin();
+		if (iter == mMap.end())
+		{
+			return FALSE;
+		}
+		*datap = (*(iter)).second;
+		mMap.erase(iter);
+
+		return TRUE;
+	}
+
+	void reprioritize(const F32 new_priority, DATA_TYPE data)
+	{
+		pqm_iter iter;
+		F32 cur_priority = mGetPriority(data);
+		LLPQMKey<DATA_TYPE> cur_key(cur_priority, data);
+		iter = mMap.find(cur_key);
+		if (iter == mMap.end())
+		{
+			llwarns << "Data not on priority queue!" << llendl;
+			// OK, try iterating through all of the data and seeing if we just screwed up the priority
+			// somehow.
+			for (iter = mMap.begin(); iter != mMap.end(); iter++)
+			{
+				if ((*(iter)).second == data)
+				{
+					llerrs << "Data on priority queue but priority not matched!" << llendl;
+				}
+			}
+			return;
+		}
+
+		mMap.erase(iter);
+		mSetPriority(data, new_priority);
+		push(new_priority, data);
+	}
+
+	S32 getLength() const
+	{
+		return (S32)mMap.size();
+	}
+
+	// Hack: public for use by the transfer manager, ugh.
+	std::map<LLPQMKey<DATA_TYPE>, DATA_TYPE> mMap;
+protected:
+	void (*mSetPriority)(DATA_TYPE &data, const F32 priority);
+	F32 (*mGetPriority)(DATA_TYPE &data);
+};
+
+#endif // LL_LLPRIQUEUEMAP_H