State machine using function pointers

state_machine.c

#include <stdio.h>

long stateStart = 0;

// fun_ptr is a pointer to function fun()  
void (*UpdateFunction)(void); 

void ManualMode(){
    //Acoes de exibir e controlar o modo manual
    if(selectButton && option == 2){ //opção 2 cancelar
        UpdateFunction = &MainMenu;
    }
}

void MainMenu(){
    // funções de exibir as opções na tela
    //...
    if(selectButton && option == 1){ // opção 1 manual
        UpdateFunction = &ManualMode;
    }
}

void SplashScreen() 
{ 
    if(millis() - stateStart < 3000){
        PrintSplash();
    }else{
        UpdateFunction = &MainMenu;
    }
}


int main()
{
    //setup
    UpdateFunction = &SplashScreen;
    
    //loop
    while(1){
        UpdateFunction();
    }
    
    return 0;
}