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/*	uint32 sched(uint32 esp)
 *	Called by the timer IRQ0 handler,
 *	returns the stack of the next task */
uint32 sched(uint32 esp)
{
	AtomicIncrement(&timer_ticks);	// Increment tick count
	if (sched_active == 0)			// Is multitasking enabled?
		return esp;					// Scheduler turned off

	tasks[current_pid].stack = esp;	// Save old esp
	switch_pid();					// Find next pid
		
	if (tasks[current_pid].state)	// Is task still running?
	{
		tasks[current_pid].spins++;
		return tasks[current_pid].stack;
	}
	else							// No active tasks
	{
		return esp;					// Don't switch - no active tasks
	}
}

Code: Select all

int exit()
{
	// We are modifying kernel structures, and so cannot interrupt
	asm volatile("cli");
	// Set up some basic task structs
	task_t *task_d = 0;
	task_t *task_r = (task_t*)ready_queue;
	//task_r is already initalized
	//While the next task is not NULL (end of Linked List)
	//Set test_r to the next task
	for(;task_r->next!=0;task_r=task_r->next)
	{
		if(task_r->next == current_task)
			task_d=task_r; // Now we have the previous task
	}
	if(!task_d) //Make sure that the above worked
		return -1;
	task_d->next = current_task->next; //Remove current_task from the list
	kfree(current_task); //Free up the memory
	switch_task(); //We must update the scheduler, or current_task will run for a bit more
	asm volatile("sti"); //Restart interrupts
	return 0;
}