#include "types.h"
#include "x86.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "proc.h"

int
sys_fork(void)
{
  return fork();
}

int
sys_clone(){
    int stack;
    int size;
    int routine;
    int arg;

    if(argint(1,&size) < 0 || size <=0 || argint(0,&stack) <0 ||
            argint(2,&routine) < 0 || argint(3,&arg)<0){
        return -1;
    }
    return clone(stack,size,routine,arg);
}

int
sys_exit(void)
{
  exit();
  return 0;  // not reached
}

int
sys_texit(void)
{
    texit();
    return 0;
}

int
sys_wait(void)
{
  return wait();
}

int
sys_kill(void)
{
  int pid;

  if(argint(0, &pid) < 0)
    return -1;
  return kill(pid);
}

int
sys_getpid(void)
{
  return proc->pid;
}

int
sys_sbrk(void)
{
  int addr;
  int n;

  if(argint(0, &n) < 0)
    return -1;
  addr = proc->sz;
  if(growproc(n) < 0)
    return -1;
  return addr;
}

int
sys_sleep(void)
{
  int n;
  uint ticks0;
  
  if(argint(0, &n) < 0)
    return -1;
  acquire(&tickslock);
  ticks0 = ticks;
  while(ticks - ticks0 < n){
    if(proc->killed){
      release(&tickslock);
      return -1;
    }
    sleep(&ticks, &tickslock);
  }
  release(&tickslock);
  return 0;
}

// return how many clock tick interrupts have occurred
// since start.
int
sys_uptime(void)
{
  uint xticks;
  
  acquire(&tickslock);
  xticks = ticks;
  release(&tickslock);
  return xticks;
}

int
sys_tsleep(void)
{
    tsleep();
    return 0;
}

int 
sys_twakeup(void)
{
    int tid;
    if(argint(0,&tid) < 0){
        return -1;
    }
        twakeup(tid);
        return 0;
}
