#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

// state dft

enum states {INIT,LEDON,LEDOFF};

// you just define your need
#define MSGARSIZE 4
typedef struct {
	int data[MSGARSIZE];
} msgTp;	

// state functions

enum states init(msgTp *msg)
{
	printf("\ninit\n");
	sleep(1);
	return LEDON; // return next state
}


enum states ledOn(msgTp *msg)
{
	printf("\nledOn\n");
	
	sleep(1);
	
	return LEDOFF;
}

enum states ledOff(msgTp *msg)
{
	printf("\nledOff\n");
	
	sleep(1);
	
	return LEDON;
}

int main()
{
	msgTp m; // for getting data to from a state
	
	enum states state = INIT;
	
	while (1) {
		switch (state) {
			case INIT:
				state = init(&m);
				break;
			case LEDON:
				state = ledOn(&m);
				break;
			case LEDOFF:
				state = ledOff(&m);
				break;
			default:
				state = INIT;
		}
	}
}

/**
 * case-switch considerations
 * Finding of the proper case can be carried out 
 * in two ways.
 * 
 * 1) if (..) else if (..) ..
 * So if you do have 100 case then in average you 
 * will do 50 if (...)
 * 
 * 2) if you order your cases in numerical order like
 * case 0:
 * ...
 * break;
 * case 1: 
 * ...
 * break;
 * and so forth
 * a jump table will be generated you just jump to the right case entry.
 * so no performance lack even in a case with several 100 entries.
 * 
 * By using the enum state above we are guaranteed the states are numbered 0,1,2,..
 * Then you just need to code our case switch in numerical order. 
 * 
 */