+/*
+ * Copyright (c) 1982, 1986, 1989, 1991 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)kern_exit.c 7.35 (Berkeley) 6/27/91
+ */
+
+#include "param.h"
+#include "systm.h"
+#include "ioctl.h"
+#include "tty.h"
+#include "time.h"
+#include "resource.h"
+#include "kernel.h"
+#include "proc.h"
+#include "buf.h"
+#include "wait.h"
+#include "file.h"
+#include "vnode.h"
+#include "syslog.h"
+#include "malloc.h"
+#include "resourcevar.h"
+
+#include "machine/cpu.h"
+#ifdef COMPAT_43
+#include "machine/reg.h"
+#include "machine/psl.h"
+#endif
+
+#include "vm/vm.h"
+#include "vm/vm_kern.h"
+
+/*
+ * Exit system call: pass back caller's arg
+ */
+/* ARGSUSED */
+rexit(p, uap, retval)
+ struct proc *p;
+ struct args {
+ int rval;
+ } *uap;
+ int *retval;
+{
+
+ exit(p, W_EXITCODE(uap->rval, 0));
+ /* NOTREACHED */
+}
+
+/*
+ * Exit: deallocate address space and other resources,
+ * change proc state to zombie, and unlink proc from allproc
+ * and parent's lists. Save exit status and rusage for wait().
+ * Check for child processes and orphan them.
+ */
+exit(p, rv)
+ register struct proc *p;
+ int rv;
+{
+ register struct proc *q, *nq;
+ register struct proc **pp;
+ int s;
+
+#ifdef PGINPROF
+ vmsizmon();
+#endif
+ MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage),
+ M_ZOMBIE, M_WAITOK);
+ /*
+ * If parent is waiting for us to exit or exec,
+ * SPPWAIT is set; we will wakeup the parent below.
+ */
+ p->p_flag &= ~(STRC|SPPWAIT);
+ p->p_flag |= SWEXIT;
+ p->p_sigignore = ~0;
+ p->p_sig = 0;
+ untimeout(realitexpire, (caddr_t)p);
+
+ /*
+ * Close open files and release open-file table.
+ * This may block!
+ */
+ fdfree(p);
+
+ /* The next two chunks should probably be moved to vmspace_exit. */
+#ifdef SYSVSHM
+ if (p->p_vmspace->vm_shm)
+ shmexit(p);
+#endif
+ /*
+ * Release user portion of address space.
+ * This releases references to vnodes,
+ * which could cause I/O if the file has been unlinked.
+ * Need to do this early enough that we can still sleep.
+ * Can't free the entire vmspace as the kernel stack
+ * may be mapped within that space also.
+ */
+ if (p->p_vmspace->vm_refcnt == 1)
+ (void) vm_map_remove(&p->p_vmspace->vm_map, VM_MIN_ADDRESS,
+ VM_MAXUSER_ADDRESS);
+
+ if (p->p_pid == 1)
+ panic("init died");
+
+ if (SESS_LEADER(p)) {
+ register struct session *sp = p->p_session;
+
+ if (sp->s_ttyvp) {
+ /*
+ * Controlling process.
+ * Signal foreground pgrp,
+ * drain controlling terminal
+ * and revoke access to controlling terminal.
+ */
+ if (sp->s_ttyp->t_session == sp) {
+ if (sp->s_ttyp->t_pgrp)
+ pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1);
+ (void) ttywait(sp->s_ttyp);
+ vgoneall(sp->s_ttyvp);
+ }
+ vrele(sp->s_ttyvp);
+ sp->s_ttyvp = NULL;
+ /*
+ * s_ttyp is not zero'd; we use this to indicate
+ * that the session once had a controlling terminal.
+ * (for logging and informational purposes)
+ */
+ }
+ sp->s_leader = NULL;
+ }
+ fixjobc(p, p->p_pgrp, 0);
+ p->p_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+#ifdef KTRACE
+ /*
+ * release trace file
+ */
+ if (p->p_tracep)
+ vrele(p->p_tracep);
+#endif
+
+ /* current process does not exist, as far as other parts of the
+ * system (clock) is concerned, since parts of it might not be
+ * there anymore */
+ curproc = NULL;
+
+ if (--p->p_limit->p_refcnt == 0) {
+ FREE(p->p_limit, M_SUBPROC);
+ p->p_limit = (struct plimit *) -1;
+ }
+
+ /*
+ * Remove proc from allproc queue and pidhash chain.
+ * Place onto zombproc. Unlink from parent's child list.
+ */
+ if (*p->p_prev = p->p_nxt)
+ p->p_nxt->p_prev = p->p_prev;
+ if (p->p_nxt = zombproc)
+ p->p_nxt->p_prev = &p->p_nxt;
+ p->p_prev = &zombproc;
+ zombproc = p;
+ p->p_stat = SZOMB;
+ for (pp = &pidhash[PIDHASH(p->p_pid)]; *pp; pp = &(*pp)->p_hash)
+ if (*pp == p) {
+ *pp = p->p_hash;
+ goto done;
+ }
+ panic("exit");
+done:
+
+ if (p->p_cptr) /* only need this if any child is S_ZOMB */
+ wakeup((caddr_t) initproc);
+ for (q = p->p_cptr; q != NULL; q = nq) {
+ nq = q->p_osptr;
+ if (nq != NULL)
+ nq->p_ysptr = NULL;
+ if (initproc->p_cptr)
+ initproc->p_cptr->p_ysptr = q;
+ q->p_osptr = initproc->p_cptr;
+ q->p_ysptr = NULL;
+ initproc->p_cptr = q;
+
+ q->p_pptr = initproc;
+ /*
+ * Traced processes are killed
+ * since their existence means someone is screwing up.
+ */
+ if (q->p_flag&STRC) {
+ q->p_flag &= ~STRC;
+ psignal(q, SIGKILL);
+ }
+ }
+ p->p_cptr = NULL;
+
+ /*
+ * Save exit status and final rusage info,
+ * adding in child rusage info and self times.
+ */
+ p->p_xstat = rv;
+ *p->p_ru = p->p_stats->p_ru;
+ p->p_ru->ru_stime = p->p_stime;
+ p->p_ru->ru_utime = p->p_utime;
+ ruadd(p->p_ru, &p->p_stats->p_cru);
+
+ /*
+ * Notify parent that we're gone.
+ */
+ psignal(p->p_pptr, SIGCHLD);
+ wakeup((caddr_t)p->p_pptr);
+#if defined(tahoe)
+ /* move this to cpu_exit */
+ p->p_addr->u_pcb.pcb_savacc.faddr = (float *)NULL;
+#endif
+ /*
+ * Finally, call machine-dependent code to release the remaining
+ * resources including address space, the kernel stack and pcb.
+ * The address space is released by "vmspace_free(p->p_vmspace)";
+ * This is machine-dependent, as we may have to change stacks
+ * or ensure that the current one isn't reallocated before we
+ * finish. cpu_exit will end with a call to swtch(), finishing
+ * our execution (pun intended).
+ */
+ cpu_exit(p);
+ /* NOTREACHED */
+}
+
+#ifdef COMPAT_43
+owait(p, uap, retval)
+ struct proc *p;
+ register struct args {
+ int pid;
+ int *status;
+ int options;
+ struct rusage *rusage;
+ int compat;
+ } *uap;
+ int *retval;
+{
+
+ uap->options = 0;
+ uap->rusage = 0;
+ uap->pid = WAIT_ANY;
+ uap->status = 0;
+ uap->compat = 1;
+ return (wait1(p, uap, retval));
+}
+
+wait4(p, uap, retval)
+ struct proc *p;
+ struct args {
+ int pid;
+ int *status;
+ int options;
+ struct rusage *rusage;
+ int compat;
+ } *uap;
+ int *retval;
+{
+
+ uap->compat = 0;
+ return (wait1(p, uap, retval));
+}
+#else
+#define wait1 wait4
+#endif
+
+/*
+ * Wait: check child processes to see if any have exited,
+ * stopped under trace, or (optionally) stopped by a signal.
+ * Pass back status and deallocate exited child's proc structure.
+ */
+wait1(q, uap, retval)
+ register struct proc *q;
+ register struct args {
+ int pid;
+ int *status;
+ int options;
+ struct rusage *rusage;
+#ifdef COMPAT_43
+ int compat;
+#endif
+ } *uap;
+ int retval[];
+{
+ register int nfound;
+ register struct proc *p;
+ int status, error;
+
+ if (uap->pid == 0)
+ uap->pid = -q->p_pgid;
+#ifdef notyet
+ if (uap->options &~ (WUNTRACED|WNOHANG))
+ return (EINVAL);
+#endif
+loop:
+ nfound = 0;
+ for (p = q->p_cptr; p; p = p->p_osptr) {
+ if (uap->pid != WAIT_ANY &&
+ p->p_pid != uap->pid && p->p_pgid != -uap->pid)
+ continue;
+ nfound++;
+ if (p->p_stat == SZOMB) {
+ retval[0] = p->p_pid;
+#ifdef COMPAT_43
+ if (uap->compat)
+ retval[1] = p->p_xstat;
+ else
+#endif
+ if (uap->status) {
+ status = p->p_xstat; /* convert to int */
+ if (error = copyout((caddr_t)&status,
+ (caddr_t)uap->status, sizeof(status)))
+ return (error);
+ }
+ if (uap->rusage && (error = copyout((caddr_t)p->p_ru,
+ (caddr_t)uap->rusage, sizeof (struct rusage))))
+ return (error);
+ p->p_xstat = 0;
+ ruadd(&q->p_stats->p_cru, p->p_ru);
+ FREE(p->p_ru, M_ZOMBIE);
+ if (--p->p_cred->p_refcnt == 0) {
+ crfree(p->p_cred->pc_ucred);
+ FREE(p->p_cred, M_SUBPROC);
+ p->p_cred = (struct pcred *) -1;
+ }
+
+ /*
+ * Finally finished with old proc entry.
+ * Unlink it from its process group and free it.
+ */
+ leavepgrp(p);
+ if (*p->p_prev = p->p_nxt) /* off zombproc */
+ p->p_nxt->p_prev = p->p_prev;
+ if (q = p->p_ysptr)
+ q->p_osptr = p->p_osptr;
+ if (q = p->p_osptr)
+ q->p_ysptr = p->p_ysptr;
+ if ((q = p->p_pptr)->p_cptr == p)
+ q->p_cptr = p->p_osptr;
+
+ /*
+ * Give machine-dependent layer a chance
+ * to free anything that cpu_exit couldn't
+ * release while still running in process context.
+ */
+ cpu_wait(p);
+ FREE(p, M_PROC);
+ nprocs--;
+ return (0);
+ }
+ if (p->p_stat == SSTOP && (p->p_flag & SWTED) == 0 &&
+ (p->p_flag & STRC || uap->options & WUNTRACED)) {
+ p->p_flag |= SWTED;
+ retval[0] = p->p_pid;
+#ifdef COMPAT_43
+ if (uap->compat) {
+ retval[1] = W_STOPCODE(p->p_xstat);
+ error = 0;
+ } else
+#endif
+ if (uap->status) {
+ status = W_STOPCODE(p->p_xstat);
+ error = copyout((caddr_t)&status,
+ (caddr_t)uap->status, sizeof(status));
+ } else
+ error = 0;
+ return (error);
+ }
+ }
+ if (nfound == 0)
+ return (ECHILD);
+ if (uap->options & WNOHANG) {
+ retval[0] = 0;
+ return (0);
+ }
+ if (error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 0))
+ return (error);
+ goto loop;
+}
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