#include "schedos-app.h"

#include "x86sync.h"

/*****************************************************************************

* schedos-1

*

* This tiny application prints red "1"s to the console.

* It yields the CPU to the kernel after each "1" using the sys_yield()

* system call. This lets the kernel (schedos-kern.c) pick another

* application to run, if it wants.

*

* The other schedos-* processes simply #include this file after defining

* PRINTCHAR appropriately.

*

*****************************************************************************/

#ifndef PRINTCHAR

#define PRINTCHAR ('1' | 0x0C00)

#endif

// UNCOMMENT THE NEXT LINE TO USE EXERCISE 8 CODE INSTEAD OF EXERCISE 6

//#define __EXERCISE_8__

// Use the following structure to choose between them:

#ifndef __EXERCISE_8__

#define __EXERCISE_6__

#endif

void

start(void)

{

int i;

for (i = 0; i < RUNCOUNT; i++) {

// Write characters to the console, yielding after each one.

//*cursorpos++ = PRINTCHAR;

// Atomic syscall version

#ifdef __EXERCISE_6__

sys_print(PRINTCHAR);

#endif

// Atomic lock version

#ifdef __EXERCISE_8__

while (atomic_swap(&lock, 1) != 0)

continue;

*cursorpos++ = PRINTCHAR;

atomic_swap(&lock, 0);

#endif

sys_yield();

}

/*// Yield forever.

while (1)

sys_yield();*/

sys_exit(0);

}