State machine program framework

state.h

#ifndef __STATE_H
#define __STATE_H

// Define state machine function pointers 
typedef void (*state_func_p)(void);    

#endif

state.c

#include "state.h"

// Record the current status , Implement state loop 
static state_func_p g_state_cur = NULL; 

//func： The state to jump to 
void main_setState(state_func_p func){
    
    g_state_cur = func;
}
//  Get current status 
state_func_p main_getState(void){
    
    return g_state_funcCur;
}

Encapsulated into get、set Function for the upper layer to call

main.c

#include "state.h"

// Idle state 
void main_stateIdle(void){
    

	// Function realization 
	
	if( Began to run ){
    
		main_setState(main_stateRun);
	}
	if( An error occurred ){
    
		main_setState(main_stateError);
	}	
}
// Running state 
void main_stateRun(void){
    

	// Function realization 
	
	if( Stop running ){
    
		main_setState(main_stateIdle);
	}
	if( An error occurred ){
    
		main_setState(main_stateError);
	}	
}

// Error status 
void main_stateError(void){
    
	
	// Function realization 
	
	if( Error elimination ){
    
		main_setState(main_stateIdle);
	}
		
}

int main(void){
    
    // Set to idle state initially 
    main_setState(main_stateIdle);
    while(1){
    
    
        (*(main_getState()))();
    }
}