Thread: Not consistent coroutines code results

Hi,

I was learning about coroutines and I like it beside I did a similar code using void pointers which contain a lot of casting, so I for now like the coroutines more.

I did a small example on desktop compiler.
Codeblocks, 64-bit machine, running on Windows 10.

This is the code parts.

1. Example functions:

Code:

bool function1(void){
    BeginCoroutine;
    printf("\n1 part1\n");
    co_delay(500);
    printf("\n1 part2\n");
    co_delay(500);
    EndCoroutine;
}


bool function2(void){
    BeginCoroutine;
    printf("\n2 part1\n");
    co_delay(500);
    printf("\n2 part2\n");
    co_delay(500);
    EndCoroutine;
}




// in function5 and function6, I on purpose doing one delay
bool function5(void){
    BeginCoroutine;
    printf("\n5 part1\n");
    co_delay(500);
    printf("\n5 part2\n");
    EndCoroutine;
}


bool function6(void){
    BeginCoroutine;
    printf("\n6 part1\n");
    co_delay(500);
    printf("\n6 part2\n");
    EndCoroutine;
}

2. Coroutines header:

Code:

//////////////////////////////////////////////////////////////////////////////////
// definitions


#define START_TASK_COUNTER(c) task_counter = c;


#define BeginCoroutine  static int state = 0;                               \
                        switch(state)                                       \
                        {                                                   \
                            case 0:


#define co_delay(prd)	do												    \
                        {												    \
							static unsigned long st_millis = 0;			    \
                            for(st_millis = millis();millis() - st_millis < prd;)\
                            {                                               \
								do			                                \
								{			                                \
									state = __LINE__;			            \
									return Yielding;                        \
									case __LINE__:			                \
									;           			                \
								}while (0);			                        \
                            }			                                    \
                        }			                                        \
                        while (0)


#define EndCoroutine    }                                                   \
                        task_counter--; 					            	\
                        printf("task %d finished\n",task_counter); 		\
                        state = 0; 					            			\
                        return Done




//////////////////////////////////////////////////////////////////////////////////
// enumerations
typedef enum { Done, Yielding } RoutineState;


// variables
uint8_t task_counter;

3. Coroutines source:

Code:

unsigned long millis(void){
    unsigned long t_val;
    t_val = GetTickCount();
    return t_val;
}

4. main

Code:

void coroutine1(void){
    START_TASK_COUNTER(2);
    printf("\ncoroutine1 -------------------------------\n");
    printf("tasks counts# %d\n",task_counter);
    while(task_counter)
    {
        function1();
        function2();
    }
}


void coroutine2(void){
    START_TASK_COUNTER(2);
    printf("\ncoroutine2 -------------------------------\n");
    printf("tasks counts# %d\n",task_counter);
    while(task_counter)
    {
        function5();
        function6();
    }
}


int main(){


    RunCoroutine(coroutine1);
    RunCoroutine(coroutine2);


    return 0;
}

=========================================

Now here 2 console outputs, one is perfect and the next one is different.

Example console output:


run#1: Perfect run time, no extra executions and each function part is in order:

Code:

coroutine1 -------------------------------
tasks counts# 2


1 part1


2 part1


1 part2


2 part2
task 1 finished
task 0 finished


coroutine2 -------------------------------
tasks counts# 2


5 part1


6 part1


5 part2
task 1 finished


6 part2
task 0 finished

run#2: Here, note that

coroutine1

has executed

2 part1

again, after the coroutine should be finished:

Code:

coroutine1 -------------------------------
tasks counts# 2


1 part1


2 part1


1 part2


2 part2
task 1 finished
task 0 finished


2 part1


coroutine2 -------------------------------
tasks counts# 2


5 part1


6 part1


5 part2
task 1 finished


6 part2
task 0 finished

What could be the problem ?