sysproc.c

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

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

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

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 myproc()->pid;
}

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

  if(argint(0, &n) < 0)
    return -1;
  addr = myproc()->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(myproc()->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_set_priority(void){
  int priority;
  if(argint(0, &priority) < 0)
    return -1;
  myproc()->priority = priority;
  return 0;
}


int sys_shutdown(void){
  outw(0xB004, 0x0 | 0x2000);
  return 0;
}

int sys_reboot(void){
  outb(0x64, 0xfe);
  return 0;
}

int sys_signal(void){
  int signum;
  int function;
  if(argint(0, &signum) < 0){
    return -1;
  }
  if(argint(1, &function) < 0){
    return -1;
  }
 
   if (signum > 0 && signum <= 4)
   {
     int value = (int)myproc()->signals[signum-1];
     myproc()->signals[signum-1] = (sighandler_t)function;
     return value;
   }
   else{
    return -1;
  };
 }
 
 int sys_getppid(void){
 return myproc()->parent->pid;
  }