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 * modification, are permitted provided that the following conditions
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 *
 * 1. Redistributions of source code must retain the above copyright
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 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
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 *    distribution.
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 *    used to endorse or promote products derived from this software
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 *
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/**
 * @file state_table.h
 *
 * Finite-State-Machine helper class for state table
 * @author: Julian Oes <julian@oes.ch>
 */

#ifndef __SYSTEMLIB_STATE_TABLE_H
#define __SYSTEMLIB_STATE_TABLE_H

class StateTable
{
public:
	typedef void (StateTable::*Action)();
	struct Tran {
		Action action;
		unsigned nextState;
	};

	StateTable(Tran const *table, unsigned nStates, unsigned nSignals)
	: myTable(table), myNsignals(nSignals), myNstates(nStates) {}

	#define NO_ACTION &StateTable::doNothing
	#define ACTION(_target) StateTable::Action(_target)

	virtual ~StateTable() {}

	void dispatch(unsigned const sig) {
		/* get transition using state table */
		Tran const *t = myTable + myState*myNsignals + sig;

		/* accept new state */
		myState = t->nextState;

		/*  */
		(this->*(t->action))();
	}
	void doNothing() {
		return;
	}
protected:
	unsigned myState;
private:
	Tran const *myTable;
	unsigned myNsignals;
	unsigned myNstates;
};

#endif