[unix-history] / usr / src / sys / kern / kern_exit.c

/*
 * Copyright (c) 1982, 1986 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 *
 *	@(#)kern_exit.c	7.4 (Berkeley) %G%
 */

#include "../machine/reg.h"
#include "../machine/psl.h"

#include "param.h"
#include "systm.h"
#include "map.h"
#include "dir.h"
#include "user.h"
#include "kernel.h"
#include "proc.h"
#include "buf.h"
#include "wait.h"
#include "vm.h"
#include "file.h"
#include "inode.h"
#include "syslog.h"
#include "malloc.h"

/*
 * Exit system call: pass back caller's arg
 */
rexit()
{
	register struct a {
		int	rval;
	} *uap;

	uap = (struct a *)u.u_ap;
	exit((uap->rval & 0377) << 8);
}

/*
 * Release resources.
 * Save u. area for parent to look at.
 * Enter zombie state.
 * Wake up parent and init processes,
 * and dispose of children.
 */
exit(rv)
	int rv;
{
	register int i;
	register struct proc *p, *q, *nq;
	register int x;

#ifdef PGINPROF
	vmsizmon();
#endif
	p = u.u_procp;
	MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage),
		M_ZOMBIE, M_WAITOK);
	p->p_flag &= ~(STRC|SULOCK);
	p->p_flag |= SWEXIT;
	p->p_sigignore = ~0;
	p->p_cpticks = 0;
	p->p_pctcpu = 0;
	for (i = 0; i < NSIG; i++)
		u.u_signal[i] = SIG_IGN;
	untimeout(realitexpire, (caddr_t)p);
	/*
	 * Release virtual memory.  If we resulted from
	 * a vfork(), instead give the resources back to
	 * the parent.
	 */
	if ((p->p_flag & SVFORK) == 0)
		vrelvm();
	else {
		p->p_flag &= ~SVFORK;
		wakeup((caddr_t)p);
		while ((p->p_flag & SVFDONE) == 0)
			sleep((caddr_t)p, PZERO - 1);
		p->p_flag &= ~SVFDONE;
	}
	for (i = 0; i <= u.u_lastfile; i++) {
		struct file *f;

		f = u.u_ofile[i];
		if (f) {
			u.u_ofile[i] = NULL;
			u.u_pofile[i] = 0;
			closef(f);
		}
	}
	ilock(u.u_cdir);
	iput(u.u_cdir);
	if (u.u_rdir) {
		ilock(u.u_rdir);
		iput(u.u_rdir);
	}
	u.u_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
	acct();
#ifdef QUOTA
	qclean();
#endif
	/*
	 * Freeing the user structure and kernel stack
	 * for the current process: have to run a bit longer
	 * using the pages which are about to be freed...
	 * vrelu will block memory allocation by raising ipl.
	 */
	vrelu(u.u_procp, 0);
	vrelpt(u.u_procp);
	if (*p->p_prev = p->p_nxt)		/* off allproc queue */
		p->p_nxt->p_prev = p->p_prev;
	if (p->p_nxt = zombproc)		/* onto zombproc */
		p->p_nxt->p_prev = &p->p_nxt;
	p->p_prev = &zombproc;
	zombproc = p;
	multprog--;
	p->p_stat = SZOMB;
	noproc = 1;
	i = PIDHASH(p->p_pid);
	x = p - proc;
	if (pidhash[i] == x)
		pidhash[i] = p->p_idhash;
	else {
		for (i = pidhash[i]; i != 0; i = proc[i].p_idhash)
			if (proc[i].p_idhash == x) {
				proc[i].p_idhash = p->p_idhash;
				goto done;
			}
		panic("exit");
	}
	if (p->p_pid == 1) {
		if (p->p_dsize == 0) {
			printf("Can't exec /etc/init (errno %d)\n", rv >> 8);
			for (;;)
				;
		} else
			panic("init died");
	}
done:
	p->p_xstat = rv;
	*p->p_ru = u.u_ru;
	ruadd(p->p_ru, &u.u_cru);
	if (p->p_cptr)		/* only need this if any child is S_ZOMB */
		wakeup((caddr_t)&proc[1]);
	for (q = p->p_cptr; q != NULL; q = nq) {
		nq = q->p_osptr;
		if (nq != NULL)
			nq->p_ysptr = NULL;
		if (proc[1].p_cptr)
			proc[1].p_cptr->p_ysptr = q;
		q->p_osptr = proc[1].p_cptr;
		q->p_ysptr = NULL;
		proc[1].p_cptr = q;

		q->p_pptr = &proc[1];
		q->p_ppid = 1;
		/*
		 * Traced processes are killed
		 * since their existence means someone is screwing up.
		 * Stopped processes are sent a hangup and a continue.
		 * This is designed to be ``safe'' for setuid
		 * processes since they must be willing to tolerate
		 * hangups anyways.
		 */
		if (q->p_flag&STRC) {
			q->p_flag &= ~STRC;
			psignal(q, SIGKILL);
		} else if (q->p_stat == SSTOP) {
			psignal(q, SIGHUP);
			psignal(q, SIGCONT);
		}
		/*
		 * Protect this process from future
		 * tty signals, clear TSTP/TTIN/TTOU if pending.
		 */
		(void) spgrp(q);
	}
	p->p_cptr = NULL;
	psignal(p->p_pptr, SIGCHLD);
	wakeup((caddr_t)p->p_pptr);
#if defined(tahoe)
	dkeyrelease(p->p_dkey), p->p_dkey = 0;
	ckeyrelease(p->p_ckey), p->p_ckey = 0;
	u.u_pcb.pcb_savacc.faddr = (float *)NULL;
#endif
	swtch();
}

wait()
{
	struct rusage ru, *rup;

	if ((u.u_ar0[PS] & PSL_ALLCC) != PSL_ALLCC) {
		u.u_error = wait1(0, (struct rusage *)0);
		return;
	}
	rup = (struct rusage *)u.u_ar0[R1];
	u.u_error = wait1(u.u_ar0[R0], &ru);
	if (u.u_error)
		return;
	if (rup != (struct rusage *)0)
		u.u_error = copyout((caddr_t)&ru, (caddr_t)rup,
		    sizeof (struct rusage));
}

/*
 * Wait system call.
 * Search for a terminated (zombie) child,
 * finally lay it to rest, and collect its status.
 * Look also for stopped (traced) children,
 * and pass back status from them.
 */
wait1(options, ru)
	register int options;
	struct rusage *ru;
{
	register f;
	register struct proc *p, *q;

	f = 0;
loop:
	q = u.u_procp;
	for (p = q->p_cptr; p; p = p->p_osptr) {
		f++;
		if (p->p_stat == SZOMB) {
			u.u_r.r_val1 = p->p_pid;
			u.u_r.r_val2 = p->p_xstat;
			p->p_xstat = 0;
			if (ru && p->p_ru)
				*ru = *p->p_ru;
			if (p->p_ru) {
				ruadd(&u.u_cru, p->p_ru);
				FREE(p->p_ru, M_ZOMBIE);
				p->p_ru = 0;
			}
			p->p_stat = NULL;
			p->p_pid = 0;
			p->p_ppid = 0;
			if (*p->p_prev = p->p_nxt)	/* off zombproc */
				p->p_nxt->p_prev = p->p_prev;
			p->p_nxt = freeproc;		/* onto freeproc */
			freeproc = p;
			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;
			p->p_pptr = 0;
			p->p_ysptr = 0;
			p->p_osptr = 0;
			p->p_cptr = 0;
			p->p_sig = 0;
			p->p_sigcatch = 0;
			p->p_sigignore = 0;
			p->p_sigmask = 0;
			p->p_pgrp = 0;
			p->p_flag = 0;
			p->p_wchan = 0;
			p->p_cursig = 0;
			return (0);
		}
		if (p->p_stat == SSTOP && (p->p_flag&SWTED)==0 &&
		    (p->p_flag&STRC || options&WUNTRACED)) {
			p->p_flag |= SWTED;
			u.u_r.r_val1 = p->p_pid;
			u.u_r.r_val2 = (p->p_cursig<<8) | WSTOPPED;
			return (0);
		}
	}
	if (f == 0)
		return (ECHILD);
	if (options&WNOHANG) {
		u.u_r.r_val1 = 0;
		return (0);
	}
	if (setjmp(&u.u_qsave)) {
		p = u.u_procp;
		if ((u.u_sigintr & sigmask(p->p_cursig)) != 0)
			return(EINTR);
		u.u_eosys = RESTARTSYS;
		return (0);
	}
	sleep((caddr_t)u.u_procp, PWAIT);
	goto loop;
}
Commit	Line	Data
da7c5cc6	1	/*
0880b18e	2	* Copyright (c) 1982, 1986 Regents of the University of California.
da7c5cc6 KM	3	* All rights reserved. The Berkeley software License Agreement
	4	* specifies the terms and conditions for redistribution.
	5	*
34d8c233	6	* @(#)kern_exit.c 7.4 (Berkeley) %G%
da7c5cc6	7	*/
a8560fa0 SL	8
	9	#include "../machine/reg.h"
	10	#include "../machine/psl.h"
	11
94368568 JB	12	#include "param.h"
	13	#include "systm.h"
	14	#include "map.h"
	15	#include "dir.h"
	16	#include "user.h"
	17	#include "kernel.h"
	18	#include "proc.h"
	19	#include "buf.h"
	20	#include "wait.h"
	21	#include "vm.h"
	22	#include "file.h"
94368568	23	#include "inode.h"
5e63dd78	24	#include "syslog.h"
61d22ffc	25	#include "malloc.h"
a8560fa0 SL	26
	27	/*
	28	* Exit system call: pass back caller's arg
	29	*/
	30	rexit()
	31	{
	32	register struct a {
	33	int rval;
	34	} *uap;
	35
	36	uap = (struct a *)u.u_ap;
	37	exit((uap->rval & 0377) << 8);
	38	}
	39
	40	/*
	41	* Release resources.
	42	* Save u. area for parent to look at.
	43	* Enter zombie state.
	44	* Wake up parent and init processes,
	45	* and dispose of children.
	46	*/
	47	exit(rv)
	48	int rv;
	49	{
	50	register int i;
1d348849	51	register struct proc p, q, *nq;
a8560fa0	52	register int x;
a8560fa0 SL	53
	54	#ifdef PGINPROF
	55	vmsizmon();
	56	#endif
	57	p = u.u_procp;
61d22ffc KM	58	MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage),
61d22ffc KM	59	M_ZOMBIE, M_WAITOK);
a8560fa0 SL	60	p->p_flag &= ~(STRC\|SULOCK);
a8560fa0 SL	61	p->p_flag \|= SWEXIT;
dd012d1e	62	p->p_sigignore = ~0;
a8560fa0 SL	63	p->p_cpticks = 0;
a8560fa0 SL	64	p->p_pctcpu = 0;
dd012d1e	65	for (i = 0; i < NSIG; i++)
a8560fa0 SL	66	u.u_signal[i] = SIG_IGN;
	67	untimeout(realitexpire, (caddr_t)p);
	68	/*
	69	* Release virtual memory. If we resulted from
	70	* a vfork(), instead give the resources back to
	71	* the parent.
	72	*/
	73	if ((p->p_flag & SVFORK) == 0)
	74	vrelvm();
	75	else {
	76	p->p_flag &= ~SVFORK;
	77	wakeup((caddr_t)p);
	78	while ((p->p_flag & SVFDONE) == 0)
	79	sleep((caddr_t)p, PZERO - 1);
	80	p->p_flag &= ~SVFDONE;
	81	}
48faa1e9	82	for (i = 0; i <= u.u_lastfile; i++) {
a8560fa0	83	struct file *f;
a8560fa0 SL	84
a8560fa0 SL	85	f = u.u_ofile[i];
48faa1e9 MK	86	if (f) {
	87	u.u_ofile[i] = NULL;
	88	u.u_pofile[i] = 0;
	89	closef(f);
	90	}
a8560fa0 SL	91	}
	92	ilock(u.u_cdir);
	93	iput(u.u_cdir);
	94	if (u.u_rdir) {
	95	ilock(u.u_rdir);
	96	iput(u.u_rdir);
	97	}
	98	u.u_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
	99	acct();
	100	#ifdef QUOTA
	101	qclean();
a8560fa0	102	#endif
db8289b8 MK	103	/*
	104	* Freeing the user structure and kernel stack
	105	* for the current process: have to run a bit longer
	106	* using the pages which are about to be freed...
	107	* vrelu will block memory allocation by raising ipl.
	108	*/
a8560fa0	109	vrelu(u.u_procp, 0);
db8289b8	110	vrelpt(u.u_procp);
1d348849 MK	111	if (p->p_prev = p->p_nxt) / off allproc queue */
	112	p->p_nxt->p_prev = p->p_prev;
	113	if (p->p_nxt = zombproc) /* onto zombproc */
	114	p->p_nxt->p_prev = &p->p_nxt;
	115	p->p_prev = &zombproc;
	116	zombproc = p;
a8560fa0 SL	117	multprog--;
	118	p->p_stat = SZOMB;
	119	noproc = 1;
	120	i = PIDHASH(p->p_pid);
	121	x = p - proc;
	122	if (pidhash[i] == x)
	123	pidhash[i] = p->p_idhash;
	124	else {
	125	for (i = pidhash[i]; i != 0; i = proc[i].p_idhash)
	126	if (proc[i].p_idhash == x) {
	127	proc[i].p_idhash = p->p_idhash;
	128	goto done;
	129	}
	130	panic("exit");
	131	}
48faa1e9 MK	132	if (p->p_pid == 1) {
48faa1e9 MK	133	if (p->p_dsize == 0) {
81cc52fa	134	printf("Can't exec /etc/init (errno %d)\n", rv >> 8);
48faa1e9 MK	135	for (;;)
	136	;
	137	} else
	138	panic("init died");
	139	}
a8560fa0 SL	140	done:
a8560fa0 SL	141	p->p_xstat = rv;
48faa1e9 MK	142	*p->p_ru = u.u_ru;
48faa1e9 MK	143	ruadd(p->p_ru, &u.u_cru);
1d348849 MK	144	if (p->p_cptr) /* only need this if any child is S_ZOMB */
	145	wakeup((caddr_t)&proc[1]);
	146	for (q = p->p_cptr; q != NULL; q = nq) {
	147	nq = q->p_osptr;
	148	if (nq != NULL)
	149	nq->p_ysptr = NULL;
	150	if (proc[1].p_cptr)
	151	proc[1].p_cptr->p_ysptr = q;
	152	q->p_osptr = proc[1].p_cptr;
	153	q->p_ysptr = NULL;
	154	proc[1].p_cptr = q;
a8560fa0	155
1d348849 MK	156	q->p_pptr = &proc[1];
	157	q->p_ppid = 1;
	158	/*
	159	* Traced processes are killed
	160	* since their existence means someone is screwing up.
	161	* Stopped processes are sent a hangup and a continue.
	162	* This is designed to be ``safe'' for setuid
	163	* processes since they must be willing to tolerate
	164	* hangups anyways.
	165	*/
	166	if (q->p_flag&STRC) {
	167	q->p_flag &= ~STRC;
	168	psignal(q, SIGKILL);
	169	} else if (q->p_stat == SSTOP) {
	170	psignal(q, SIGHUP);
	171	psignal(q, SIGCONT);
a8560fa0	172	}
1d348849 MK	173	/*
	174	* Protect this process from future
	175	* tty signals, clear TSTP/TTIN/TTOU if pending.
	176	*/
f6ab5a0c	177	(void) spgrp(q);
1d348849	178	}
bdf8c113	179	p->p_cptr = NULL;
a8560fa0 SL	180	psignal(p->p_pptr, SIGCHLD);
a8560fa0 SL	181	wakeup((caddr_t)p->p_pptr);
fb1db32c MK	182	#if defined(tahoe)
	183	dkeyrelease(p->p_dkey), p->p_dkey = 0;
	184	ckeyrelease(p->p_ckey), p->p_ckey = 0;
	185	u.u_pcb.pcb_savacc.faddr = (float *)NULL;
	186	#endif
a8560fa0 SL	187	swtch();
	188	}
	189
	190	wait()
	191	{
	192	struct rusage ru, *rup;
	193
	194	if ((u.u_ar0[PS] & PSL_ALLCC) != PSL_ALLCC) {
	195	u.u_error = wait1(0, (struct rusage *)0);
	196	return;
	197	}
	198	rup = (struct rusage *)u.u_ar0[R1];
	199	u.u_error = wait1(u.u_ar0[R0], &ru);
	200	if (u.u_error)
	201	return;
326bf897 SL	202	if (rup != (struct rusage *)0)
	203	u.u_error = copyout((caddr_t)&ru, (caddr_t)rup,
	204	sizeof (struct rusage));
a8560fa0 SL	205	}
a8560fa0 SL	206
a8560fa0 SL	207	/*
	208	* Wait system call.
	209	* Search for a terminated (zombie) child,
	210	* finally lay it to rest, and collect its status.
	211	* Look also for stopped (traced) children,
	212	* and pass back status from them.
	213	*/
	214	wait1(options, ru)
	215	register int options;
	216	struct rusage *ru;
	217	{
	218	register f;
	219	register struct proc p, q;
	220
	221	f = 0;
	222	loop:
1d348849 MK	223	q = u.u_procp;
1d348849 MK	224	for (p = q->p_cptr; p; p = p->p_osptr) {
a8560fa0 SL	225	f++;
	226	if (p->p_stat == SZOMB) {
	227	u.u_r.r_val1 = p->p_pid;
	228	u.u_r.r_val2 = p->p_xstat;
	229	p->p_xstat = 0;
5e63dd78	230	if (ru && p->p_ru)
a8560fa0	231	ru = p->p_ru;
5e63dd78 SL	232	if (p->p_ru) {
5e63dd78 SL	233	ruadd(&u.u_cru, p->p_ru);
61d22ffc	234	FREE(p->p_ru, M_ZOMBIE);
5e63dd78 SL	235	p->p_ru = 0;
5e63dd78 SL	236	}
a8560fa0 SL	237	p->p_stat = NULL;
	238	p->p_pid = 0;
	239	p->p_ppid = 0;
1d348849 MK	240	if (p->p_prev = p->p_nxt) / off zombproc */
	241	p->p_nxt->p_prev = p->p_prev;
	242	p->p_nxt = freeproc; /* onto freeproc */
	243	freeproc = p;
a8560fa0 SL	244	if (q = p->p_ysptr)
	245	q->p_osptr = p->p_osptr;
	246	if (q = p->p_osptr)
	247	q->p_ysptr = p->p_ysptr;
	248	if ((q = p->p_pptr)->p_cptr == p)
	249	q->p_cptr = p->p_osptr;
	250	p->p_pptr = 0;
	251	p->p_ysptr = 0;
	252	p->p_osptr = 0;
	253	p->p_cptr = 0;
	254	p->p_sig = 0;
dd012d1e SL	255	p->p_sigcatch = 0;
	256	p->p_sigignore = 0;
	257	p->p_sigmask = 0;
a8560fa0 SL	258	p->p_pgrp = 0;
	259	p->p_flag = 0;
	260	p->p_wchan = 0;
	261	p->p_cursig = 0;
	262	return (0);
	263	}
	264	if (p->p_stat == SSTOP && (p->p_flag&SWTED)==0 &&
	265	(p->p_flag&STRC \|\| options&WUNTRACED)) {
	266	p->p_flag \|= SWTED;
	267	u.u_r.r_val1 = p->p_pid;
	268	u.u_r.r_val2 = (p->p_cursig<<8) \| WSTOPPED;
	269	return (0);
	270	}
	271	}
dd012d1e	272	if (f == 0)
a8560fa0	273	return (ECHILD);
a8560fa0 SL	274	if (options&WNOHANG) {
	275	u.u_r.r_val1 = 0;
	276	return (0);
	277	}
fe7f81f4 KM	278	if (setjmp(&u.u_qsave)) {
fe7f81f4 KM	279	p = u.u_procp;
9f49ba41	280	if ((u.u_sigintr & sigmask(p->p_cursig)) != 0)
fe7f81f4	281	return(EINTR);
a8560fa0 SL	282	u.u_eosys = RESTARTSYS;
	283	return (0);
	284	}
	285	sleep((caddr_t)u.u_procp, PWAIT);
	286	goto loop;
	287	}