/*
 * $Id: kern_sched.h,v 1.2 2007/11/20 12:57:37 nbrk Exp $
 */
#ifndef _SYS_KERN_SCHED_H
#define _SYS_KERN_SCHED_H
#include <sys/types.h>

/*
 * Task header is used by user to describe task in config.c
 */
struct taskheader {
	const char *th_name; 				/* task name */
	uint8_t 	th_priority; 			/* priority, bigger the value = higher priority */
	void 		(*th_enter)(void); 		/* entry point */
};

/*
 * Kernel sees each system task as struct task;
 * it is used for scheduling and context switches.
 */
struct task {
	struct taskheader 	*ta_theader; 	/* points to user-described data */
	uint8_t 			ta_taskid; 		/* task id (TID) */

	uint8_t 			ta_state; 		/* task state (running, blocked, etc.) */
	uint32_t 			ta_timeo; 		/* timeout (in HZ) if task is blocked */ 
	uint32_t 			*ta_stackptr; 	/* task stack addr (used to switch-back to that task) */

	struct task 		*ta_nextp;
};

/*
 * Tasks states.
 */
#define TASK_NOSCHED 	0x00 	/* task not ready or halted; will not schedule this */
#define TASK_READY 		0x01 	/* ready for schedule */
#define TASK_RUNNING 	0x02 	/* running now */
#define TASK_SLEEPING 	0x04 	/* task waits for (planned) timeout */


/*
 * Functions.
 */
void 	sched_init(void);


#endif /* not _SYS_KERN_SCHED_H */