Imported existing code

indra/llcharacter/llstatemachine.h

@@ -0,0 +1,153 @@
+/** 
+ * @file llstatemachine.h
+ * @brief LLStateMachine class header file.
+ *
+ * $LicenseInfo:firstyear=2001&license=viewergpl$
+ * 
+ * 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 LL_LLSTATEMACHINE_H
+#define LL_LLSTATEMACHINE_H
+
+#include <string>
+
+#include "llerror.h"
+#include <map>
+
+class LLUniqueID
+{
+	friend bool	operator==(const LLUniqueID &a, const LLUniqueID &b);
+	friend bool	operator!=(const LLUniqueID &a, const LLUniqueID &b);
+protected:
+	static U32	sNextID;
+	U32			mId;
+public:
+	LLUniqueID(){mId = sNextID++;}
+	virtual ~LLUniqueID(){}
+	U32		getID() {return mId;}
+};
+
+class LLFSMTransition : public LLUniqueID
+{
+public:
+	LLFSMTransition() : LLUniqueID(){};
+	virtual std::string getName()const { return "unnamed"; }
+};
+
+class LLFSMState : public LLUniqueID
+{
+public:
+	LLFSMState() : LLUniqueID(){};
+	virtual void onEntry(void *){};
+	virtual void onExit(void *){};
+	virtual void execute(void *){};
+	virtual std::string getName() const { return "unnamed"; }
+};
+
+class LLStateDiagram
+{
+typedef std::map<LLFSMTransition*, LLFSMState*> Transitions;
+
+friend std::ostream& operator<<(std::ostream &s, LLStateDiagram &FSM);
+friend class LLStateMachine;
+
+protected:
+	typedef std::map<LLFSMState*, Transitions> StateMap;
+	StateMap			mStates;
+	Transitions			mDefaultTransitions;
+	LLFSMState*			mDefaultState;
+	BOOL				mUseDefaultState;
+
+public:
+	LLStateDiagram();
+	virtual ~LLStateDiagram();
+
+protected:
+	// add a state to the state graph, executed implicitly when adding transitions
+	BOOL addState(LLFSMState *state);
+
+	// add a directed transition between 2 states
+	BOOL addTransition(LLFSMState& start_state, LLFSMState& end_state, LLFSMTransition& transition);
+
+	// add an undirected transition between 2 states
+	BOOL addUndirectedTransition(LLFSMState& start_state, LLFSMState& end_state, LLFSMTransition& transition);
+
+	// add a transition that is taken if none other exist
+	void addDefaultTransition(LLFSMState& end_state, LLFSMTransition& transition);
+
+	// process a possible transition, and get the resulting state
+	LLFSMState* processTransition(LLFSMState& start_state, LLFSMTransition& transition);
+
+	// add a transition that exists for every state
+	void setDefaultState(LLFSMState& default_state);
+
+	// return total number of states with no outgoing transitions
+	S32 numDeadendStates();
+
+	// does this state exist in the state diagram?
+	BOOL stateIsValid(LLFSMState& state);
+
+	// get a state pointer by ID
+	LLFSMState* getState(U32 state_id);
+
+public:
+	// save the graph in a DOT file for rendering and visualization
+	BOOL saveDotFile(const std::string& filename);
+};
+
+class LLStateMachine
+{
+protected:
+	LLFSMState*			mCurrentState;
+	LLFSMState*			mLastState;
+	LLFSMTransition*	mLastTransition;
+	LLStateDiagram*		mStateDiagram;
+
+public:
+	LLStateMachine();
+	virtual ~LLStateMachine();
+
+	// set state diagram
+	void setStateDiagram(LLStateDiagram* diagram);
+
+	// process this transition
+	void processTransition(LLFSMTransition &transition, void* user_data);
+
+	// returns current state
+	LLFSMState*	getCurrentState() const;
+
+	// execute current state
+	void runCurrentState(void *data);
+
+	// set state by state pointer
+	BOOL setCurrentState(LLFSMState *initial_state, void* user_data, BOOL skip_entry = TRUE);
+
+	// set state by unique ID
+	BOOL setCurrentState(U32 state_id, void* user_data, BOOL skip_entry = TRUE);
+};
+
+#endif //_LL_LLSTATEMACHINE_H