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"

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 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;
}

// Halt (shutdown) the system.
int
sys_halt(void) {
    //TODO: serial_flush,filesys_done
    cprintf("** Shutting down system **\n");
    char *p = "Shutdown";
    for (; *p; p++) {
        outw(0xB004, (uchar) *p);
        outb(0x8900, (uchar) *p);
    }
    return 0;
}