#ifndef _SCHED_H
#define _SCHED_H

#include <signal.h>
#include <stdint.h>
#include <unistd.h>

/* TODO: change const 10 to tick rate */
#define uptime() ((long) (ticks * 10))

#define TSTATE_RUNNING          0
#define TSTATE_INTERRUPTIBLE    1
#define TSTATE_UNINTERRUPTIBLE  2
#define TSTATE_ZOMBIE           3
#define TSTATE_STOPPED          4

struct tss_struct {
  uint32_t prevt;
  uint32_t esp0;
  uint32_t ss0;
  uint32_t esp1;
  uint32_t ss1;
  uint32_t esp2;
  uint32_t ss2;
  uint32_t cr3;
  uint32_t eip;
  uint32_t eflags;
  uint32_t eax;
  uint32_t ecx;
  uint32_t edx;
  uint32_t ebx;
  uint32_t esp;
  uint32_t ebp;
  uint32_t esi;
  uint32_t edi;
  uint32_t es;
  uint32_t cs;
  uint32_t ss;
  uint32_t ds;
  uint32_t fs;
  uint32_t gs;
  uint32_t ldt;
  uint32_t io_map;
} __attribute__((packed));

/*
 * WARNING: do not modify this structure
 * unless the offsets defined in traps.s
 * are updated
 */

struct task_struct {
  pid_t pid;
  int state;
  uint32_t signal;
  int ctty;
  unsigned int alarm;
  void *sig_handlers[NRSIG];
  struct tss_struct tss;
} __attribute__((packed));

extern struct task_struct *ctask;
extern uint32_t ticks;

void sched_init(void);
void reschedule(void);

void wake_up(struct task_struct**);
void sleep_on(struct task_struct**);
void interruptible_sleep_on(struct task_struct**);

#endif