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

/*	kern_proc.c	3.21	%G%	*/

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/map.h"
#include "../h/mtpr.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/proc.h"
#include "../h/buf.h"
#include "../h/reg.h"
#include "../h/inode.h"
#include "../h/seg.h"
#include "../h/acct.h"
#include "/usr/include/wait.h"
#include "../h/pte.h"
#include "../h/vm.h"
#include "../h/text.h"
#include "../h/psl.h"
#include "../h/vlimit.h"
#include "../h/file.h"

/*
 * exec system call, with and without environments.
 */
struct execa {
	char	*fname;
	char	**argp;
	char	**envp;
};

exec()
{
	((struct execa *)u.u_ap)->envp = NULL;
	exece();
}

exece()
{
	register nc;
	register char *cp;
	register struct buf *bp;
	register struct execa *uap;
	int na, ne, ucp, ap, c;
	struct inode *ip;
	swblk_t bno;

	if ((ip = namei(uchar, 0)) == NULL)
		return;
	bno = 0;
	bp = 0;
	if(access(ip, IEXEC))
		goto bad;
	if((ip->i_mode & IFMT) != IFREG ||
	   (ip->i_mode & (IEXEC|(IEXEC>>3)|(IEXEC>>6))) == 0) {
		u.u_error = EACCES;
		goto bad;
	}
	/*
	 * Collect arguments on "file" in swap space.
	 */
	na = 0;
	ne = 0;
	nc = 0;
	uap = (struct execa *)u.u_ap;
	if ((bno = malloc(argmap, ctod(clrnd((int) btoc(NCARGS))))) == 0) {
		swkill(u.u_procp, "exece");
		goto bad;
	}
	if (bno % CLSIZE)
		panic("execa malloc");
	if (uap->argp) for (;;) {
		ap = NULL;
		if (uap->argp) {
			ap = fuword((caddr_t)uap->argp);
			uap->argp++;
		}
		if (ap==NULL && uap->envp) {
			uap->argp = NULL;
			if ((ap = fuword((caddr_t)uap->envp)) == NULL)
				break;
			uap->envp++;
			ne++;
		}
		if (ap==NULL)
			break;
		na++;
		if(ap == -1)
			u.u_error = EFAULT;
		do {
			if (nc >= NCARGS-1)
				u.u_error = E2BIG;
			if ((c = fubyte((caddr_t)ap++)) < 0)
				u.u_error = EFAULT;
			if (u.u_error) {
				if (bp)
					brelse(bp);
				bp = 0;
				goto badarg;
			}
			if ((nc&BMASK) == 0) {
				if (bp)
					bdwrite(bp);
				bp = getblk(argdev,
				    (daddr_t)(dbtofsb(bno)+(nc>>BSHIFT)));
				cp = bp->b_un.b_addr;
			}
			nc++;
			*cp++ = c;
		} while (c>0);
	}
	if (bp)
		bdwrite(bp);
	bp = 0;
	nc = (nc + NBPW-1) & ~(NBPW-1);
	if (getxfile(ip, nc) || u.u_error) {
badarg:
		for (c = 0; c < nc; c += BSIZE)
			if (bp = baddr(argdev, dbtofsb(bno)+(c>>BSHIFT))) {
				bp->b_flags |= B_AGE;		/* throw away */
				bp->b_flags &= ~B_DELWRI;	/* cancel io */
				brelse(bp);
				bp = 0;
			}
		goto bad;
	}

	/*
	 * copy back arglist
	 */

	ucp = USRSTACK - nc - NBPW;
	ap = ucp - na*NBPW - 3*NBPW;
	u.u_ar0[SP] = ap;
	(void) suword((caddr_t)ap, na-ne);
	nc = 0;
	for (;;) {
		ap += NBPW;
		if (na==ne) {
			(void) suword((caddr_t)ap, 0);
			ap += NBPW;
		}
		if (--na < 0)
			break;
		(void) suword((caddr_t)ap, ucp);
		do {
			if ((nc&BMASK) == 0) {
				if (bp)
					brelse(bp);
				bp = bread(argdev,
				    (daddr_t)(dbtofsb(bno)+(nc>>BSHIFT)));
				bp->b_flags |= B_AGE;		/* throw away */
				bp->b_flags &= ~B_DELWRI;	/* cancel io */
				cp = bp->b_un.b_addr;
			}
			(void) subyte((caddr_t)ucp++, (c = *cp++));
			nc++;
		} while(c&0377);
	}
	(void) suword((caddr_t)ap, 0);
	(void) suword((caddr_t)ucp, 0);
	setregs();
bad:
	if (bp)
		brelse(bp);
	if (bno)
		mfree(argmap, ctod(clrnd((int) btoc(NCARGS))), bno);
	iput(ip);
}

/*
 * Read in and set up memory for executed file.
 * Zero return is normal;
 * non-zero means only the text is being replaced
 */
getxfile(ip, nargc)
register struct inode *ip;
{
	register sep;
	register size_t ts, ds, ss;
	int overlay;
	int pagi = 0;

	/*
	 * read in first few bytes
	 * of file for segment
	 * sizes:
	 * ux_mag = 407/410/411/405
	 *  407 is plain executable
	 *  410 is RO text
	 *  411 is separated ID
	 *  405 is overlaid text
	 *  412 is demand paged plain executable (NOT IMPLEMENTED)
	 *  413 is demand paged RO text
	 */

	u.u_base = (caddr_t)&u.u_exdata;
	u.u_count = sizeof(u.u_exdata);
	u.u_offset = 0;
	u.u_segflg = 1;
	readi(ip);
	u.u_segflg = 0;
	if(u.u_error)
		goto bad;
	if (u.u_count!=0) {
		u.u_error = ENOEXEC;
		goto bad;
	}
	sep = 0;
	overlay = 0;
	switch (u.u_exdata.ux_mag) {

	case 0405:
		overlay++;
		break;

	case 0412:
		u.u_error = ENOEXEC;
		goto bad;

	case 0407:
		u.u_exdata.ux_dsize += u.u_exdata.ux_tsize;
		u.u_exdata.ux_tsize = 0;
		break;

	case 0413:
		pagi = SPAGI;
		/* fall into ... */

	case 0410:
		if (u.u_exdata.ux_tsize == 0) {
			u.u_error = ENOEXEC;
			goto bad;
		}
		break;

	case 0411:
		u.u_error = ENOEXEC;
		goto bad;

	default:
		u.u_error = ENOEXEC;
		goto bad;
	}
	if(u.u_exdata.ux_tsize!=0 && (ip->i_flag&ITEXT)==0 && ip->i_count!=1) {
		register struct file *fp;

		for (fp = file; fp < &file[NFILE]; fp++)
			if (fp->f_inode == ip && (fp->f_flag&FWRITE)) {
				u.u_error = ETXTBSY;
				goto bad;
			}
	}

	/*
	 * find text and data sizes
	 * try them out for possible
	 * exceed of max sizes
	 */

	ts = clrnd(btoc(u.u_exdata.ux_tsize));
	ds = clrnd(btoc((u.u_exdata.ux_dsize+u.u_exdata.ux_bsize)));
	ss = clrnd(SSIZE + btoc(nargc));
	if (overlay) {
		if ((u.u_procp->p_flag & SPAGI) ||
		    u.u_sep==0 && ctos(ts) != ctos(u.u_tsize) || nargc) {
			u.u_error = ENOMEM;
			goto bad;
		}
		ds = u.u_dsize;
		ss = u.u_ssize;
		sep = u.u_sep;
		xfree();
		xalloc(ip, pagi);
		u.u_ar0[PC] = u.u_exdata.ux_entloc + 2; /* skip over entry mask */
	} else {
		if (chksize(ts, ds, ss))
			goto bad;
		u.u_cdmap = zdmap;
		u.u_csmap = zdmap;
		if (swpexpand(ds, ss, &u.u_cdmap, &u.u_csmap) == NULL)
			goto bad;

		/*
		 * At this point, committed to the new image!
		 * Release virtual memory resources of old process, and
		 * initialize the virtual memory of the new process.
		 * If we resulted from vfork(), instead wakeup our
		 * parent who will set SVFDONE when he has taken back
		 * our resources.
		 */
		u.u_prof.pr_scale = 0;
		if ((u.u_procp->p_flag & SVFORK) == 0)
			vrelvm();
		else {
			u.u_procp->p_flag &= ~SVFORK;
			u.u_procp->p_flag |= SKEEP;
			wakeup((caddr_t)u.u_procp);
			while ((u.u_procp->p_flag & SVFDONE) == 0)
				sleep((caddr_t)u.u_procp, PZERO - 1);
			u.u_procp->p_flag &= ~(SVFDONE|SKEEP);
		}
		u.u_procp->p_flag &= ~(SPAGI|SANOM|SUANOM);
		u.u_procp->p_flag |= pagi;
		u.u_dmap = u.u_cdmap;
		u.u_smap = u.u_csmap;
		vgetvm(ts, ds, ss);

		if (pagi == 0) {
			/*
			 * Read in data segment.
			 */
			u.u_base = (char *)ctob(ts);
			u.u_offset = sizeof(u.u_exdata)+u.u_exdata.ux_tsize;
			u.u_count = u.u_exdata.ux_dsize;
			readi(ip);
		}
		xalloc(ip, pagi);
		if (pagi && u.u_procp->p_textp)
			vinifod((struct fpte *)dptopte(u.u_procp, 0),
			    PG_FTEXT, u.u_procp->p_textp->x_iptr,
			    1 + ts/CLSIZE, (int)btoc(u.u_exdata.ux_dsize));

		/* THIS SHOULD BE DONE AT A LOWER LEVEL, IF AT ALL */
		mtpr(TBIA, 0);

		/*
		 * set SUID/SGID protections, if no tracing
		 */
		if ((u.u_procp->p_flag&STRC)==0) {
			if(ip->i_mode&ISUID)
				if(u.u_uid != 0) {
					u.u_uid = ip->i_uid;
					u.u_procp->p_uid = ip->i_uid;
				}
			if(ip->i_mode&ISGID)
				u.u_gid = ip->i_gid;
		} else
			psignal(u.u_procp, SIGTRAP);
	}
	u.u_tsize = ts;
	u.u_dsize = ds;
	u.u_ssize = ss;
	u.u_sep = sep;
bad:
	return(overlay);
}

/*
 * Clear registers on exec
 */
setregs()
{
	register int (**rp)();
	register i;
	long sigmask;

	for(rp = &u.u_signal[0], sigmask = 1L; rp < &u.u_signal[NSIG];
	    sigmask <<= 1, rp++) {
		switch (*rp) {

		case SIG_IGN:
		case SIG_DFL:
		case SIG_HOLD:
			continue;

		default:
			/*
			 * Normal or deferring catch; revert to default.
			 */
			(void) spl6();
			*rp = SIG_DFL;
			if ((int)*rp & 1)
				u.u_procp->p_siga0 |= sigmask;
			else
				u.u_procp->p_siga1 &= ~sigmask;
			if ((int)*rp & 2)
				u.u_procp->p_siga1 |= sigmask;
			else
				u.u_procp->p_siga1 &= ~sigmask;
			(void) spl0();
			continue;
		}
	}
/*
	for(rp = &u.u_ar0[0]; rp < &u.u_ar0[16];)
		*rp++ = 0;
*/
	u.u_ar0[PC] = u.u_exdata.ux_entloc + 2; /* skip over entry mask */
	for(i=0; i<NOFILE; i++) {
		if (u.u_pofile[i]&EXCLOSE) {
			closef(u.u_ofile[i]);
			u.u_ofile[i] = NULL;
			u.u_pofile[i] &= ~EXCLOSE;
		}
	}
	/*
	 * Remember file name for accounting.
	 */
	u.u_acflag &= ~AFORK;
	bcopy((caddr_t)u.u_dbuf, (caddr_t)u.u_comm, DIRSIZ);
}

/*
 * 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)
{
	register int i;
	register struct proc *p, *q;
	register struct file *f;
	register int x;

#ifdef PGINPROF
	vmsizmon();
#endif
	p = u.u_procp;
	p->p_flag &= ~(STRC|SULOCK);
	p->p_flag |= SWEXIT;
	p->p_clktim = 0;
	(void) spl6();
	if ((int)SIG_IGN & 1)
		p->p_siga0 = ~0;
	else
		p->p_siga0 = 0;
	if ((int)SIG_IGN & 2)
		p->p_siga1 = ~0;
	else
		p->p_siga1 = 0;
	(void) spl0();
	p->p_aveflt = 0;
	for(i=0; i<NSIG; i++)
		u.u_signal[i] = SIG_IGN;
	/*
	 * 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<NOFILE; i++) {
		f = u.u_ofile[i];
		u.u_ofile[i] = NULL;
		closef(f);
	}
	plock(u.u_cdir);
	iput(u.u_cdir);
	if (u.u_rdir) {
		plock(u.u_rdir);
		iput(u.u_rdir);
	}
	u.u_limit[LIM_FSIZE] = INFINITY;
	acct();
	vrelpt(u.u_procp);
	vrelu(u.u_procp, 0);
	multprog--;
/*	spl7();			/* clock will get mad because of overlaying */
	noproc = 1;
	p->p_stat = SZOMB;
	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");
	}
done:
	((struct xproc *)p)->xp_xstat = rv;		/* overlay */
	((struct xproc *)p)->xp_vm = u.u_vm;		/* overlay */
	vmsadd(&((struct xproc *)p)->xp_vm, &u.u_cvm);
	for(q = &proc[0]; q < &proc[NPROC]; q++)
		if(q->p_pptr == p) {
			q->p_pptr = &proc[1];
			q->p_ppid = 1;
			wakeup((caddr_t)&proc[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,
			 * and set SDETACH bit on procs.
			 */
			spgrp(q, -1);
		}
	wakeup((caddr_t)p->p_pptr);
	psignal(p->p_pptr, SIGCHLD);
	swtch();
}

wait()
{
	struct vtimes vm;
	struct vtimes *vp;

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

/*
 * 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, vp)
	register options;
	struct vtimes *vp;
{
	register f;
	register struct proc *p;

	f = 0;
loop:
	for(p = &proc[0]; p < &proc[NPROC]; p++)
	if(p->p_pptr == u.u_procp) {
		f++;
		if(p->p_stat == SZOMB) {
			u.u_r.r_val1 = p->p_pid;
			u.u_r.r_val2 = ((struct xproc *)p)->xp_xstat;
			((struct xproc *)p)->xp_xstat = 0;
			if (vp)
				*vp = ((struct xproc *)p)->xp_vm;
			vmsadd(&u.u_cvm, &((struct xproc *)p)->xp_vm);
			((struct xproc *)p)->xp_vm = zvms;
			p->p_stat = NULL;
			p->p_pid = 0;
			p->p_ppid = 0;
			p->p_pptr = 0;
			p->p_sig = 0;
			p->p_siga0 = 0;
			p->p_siga1 = 0;
			p->p_pgrp = 0;
			p->p_flag = 0;
			p->p_wchan = 0;
			p->p_cursig = 0;
			return;
		}
		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;
		}
	}
	if (f==0) {
		u.u_error = ECHILD;
		return;
	}
	if (options&WNOHANG) {
		u.u_r.r_val1 = 0;
		return;
	}
/*
	if (setjmp(u.u_qsav)) {
		u.u_eosys = RESTARTSYS;
		return;
	}
*/
	sleep((caddr_t)u.u_procp, PWAIT);
	goto loop;
}

/*
 * fork system call.
 */
fork()
{

	u.u_cdmap = zdmap;
	u.u_csmap = zdmap;
	if (swpexpand(u.u_dsize, u.u_ssize, &u.u_cdmap, &u.u_csmap) == 0) {
		u.u_r.r_val2 = 0;
		return;
	}
	fork1(0);
}

fork1(isvfork)
{
	register struct proc *p1, *p2;
	register a;

	a = 0;
	p2 = NULL;
	for(p1 = &proc[0]; p1 < &proc[NPROC]; p1++) {
		if (p1->p_stat==NULL && p2==NULL)
			p2 = p1;
		else {
			if (p1->p_uid==u.u_uid && p1->p_stat!=NULL)
				a++;
		}
	}
	/*
	 * Disallow if
	 *  No processes at all;
	 *  not su and too many procs owned; or
	 *  not su and would take last slot.
	 */
	if (p2==NULL || (u.u_uid!=0 && (p2==&proc[NPROC-1] || a>MAXUPRC))) {
		u.u_error = EAGAIN;
		if (!isvfork) {
			(void) vsexpand(0, &u.u_cdmap, 1);
			(void) vsexpand(0, &u.u_csmap, 1);
		}
		goto out;
	}
	p1 = u.u_procp;
	if(newproc(isvfork)) {
		u.u_r.r_val1 = p1->p_pid;
		u.u_r.r_val2 = 1;  /* child */
		u.u_start = time;
		u.u_acflag = AFORK;
		return;
	}
	u.u_r.r_val1 = p2->p_pid;

out:
	u.u_r.r_val2 = 0;
}

/*
 * break system call.
 *  -- bad planning: "break" is a dirty word in C.
 */
sbreak()
{
	struct a {
		char	*nsiz;
	};
	register int n, d;

	/*
	 * set n to new data size
	 * set d to new-old
	 */

	n = btoc(((struct a *)u.u_ap)->nsiz);
	if (!u.u_sep)
		n -= ctos(u.u_tsize) * stoc(1);
	if (n < 0)
		n = 0;
	d = clrnd(n - u.u_dsize);
	if (ctob(u.u_dsize+d) > u.u_limit[LIM_DATA]) {
		u.u_error = ENOMEM;
		return;
	}
	if (chksize(u.u_tsize, u.u_dsize+d, u.u_ssize))
		return;
	if (swpexpand(u.u_dsize+d, u.u_ssize, &u.u_dmap, &u.u_smap)==0)
		return;
	expand(d, P0BR);
}
Commit	Line	Data
3ca1542b	1	/* kern_proc.c 3.21 %G% */
29dd101b BJ	2
	3	#include "../h/param.h"
	4	#include "../h/systm.h"
	5	#include "../h/map.h"
	6	#include "../h/mtpr.h"
	7	#include "../h/dir.h"
	8	#include "../h/user.h"
	9	#include "../h/proc.h"
	10	#include "../h/buf.h"
	11	#include "../h/reg.h"
	12	#include "../h/inode.h"
	13	#include "../h/seg.h"
	14	#include "../h/acct.h"
8643403f	15	#include "/usr/include/wait.h"
29dd101b BJ	16	#include "../h/pte.h"
	17	#include "../h/vm.h"
	18	#include "../h/text.h"
bdfe5b0f	19	#include "../h/psl.h"
b07c4d64	20	#include "../h/vlimit.h"
3ca1542b	21	#include "../h/file.h"
29dd101b BJ	22
	23	/*
	24	* exec system call, with and without environments.
	25	*/
	26	struct execa {
	27	char *fname;
	28	char **argp;
	29	char **envp;
	30	};
	31
	32	exec()
	33	{
	34	((struct execa *)u.u_ap)->envp = NULL;
	35	exece();
	36	}
	37
	38	exece()
	39	{
	40	register nc;
	41	register char *cp;
	42	register struct buf *bp;
	43	register struct execa *uap;
	44	int na, ne, ucp, ap, c;
	45	struct inode *ip;
	46	swblk_t bno;
	47
	48	if ((ip = namei(uchar, 0)) == NULL)
	49	return;
	50	bno = 0;
	51	bp = 0;
	52	if(access(ip, IEXEC))
	53	goto bad;
	54	if((ip->i_mode & IFMT) != IFREG \|\|
	55	(ip->i_mode & (IEXEC\|(IEXEC>>3)\|(IEXEC>>6))) == 0) {
	56	u.u_error = EACCES;
	57	goto bad;
	58	}
	59	/*
	60	* Collect arguments on "file" in swap space.
	61	*/
	62	na = 0;
	63	ne = 0;
	64	nc = 0;
	65	uap = (struct execa *)u.u_ap;
41888f16	66	if ((bno = malloc(argmap, ctod(clrnd((int) btoc(NCARGS))))) == 0) {
29dd101b BJ	67	swkill(u.u_procp, "exece");
	68	goto bad;
	69	}
	70	if (bno % CLSIZE)
	71	panic("execa malloc");
	72	if (uap->argp) for (;;) {
	73	ap = NULL;
	74	if (uap->argp) {
	75	ap = fuword((caddr_t)uap->argp);
	76	uap->argp++;
	77	}
	78	if (ap==NULL && uap->envp) {
	79	uap->argp = NULL;
	80	if ((ap = fuword((caddr_t)uap->envp)) == NULL)
	81	break;
	82	uap->envp++;
	83	ne++;
	84	}
	85	if (ap==NULL)
	86	break;
	87	na++;
	88	if(ap == -1)
	89	u.u_error = EFAULT;
	90	do {
	91	if (nc >= NCARGS-1)
	92	u.u_error = E2BIG;
	93	if ((c = fubyte((caddr_t)ap++)) < 0)
	94	u.u_error = EFAULT;
64d6118b BJ	95	if (u.u_error) {
	96	if (bp)
	97	brelse(bp);
	98	bp = 0;
29dd101b	99	goto badarg;
64d6118b	100	}
29dd101b BJ	101	if ((nc&BMASK) == 0) {
	102	if (bp)
	103	bdwrite(bp);
41888f16 BJ	104	bp = getblk(argdev,
41888f16 BJ	105	(daddr_t)(dbtofsb(bno)+(nc>>BSHIFT)));
29dd101b BJ	106	cp = bp->b_un.b_addr;
	107	}
	108	nc++;
	109	*cp++ = c;
	110	} while (c>0);
	111	}
	112	if (bp)
	113	bdwrite(bp);
	114	bp = 0;
	115	nc = (nc + NBPW-1) & ~(NBPW-1);
	116	if (getxfile(ip, nc) \|\| u.u_error) {
	117	badarg:
	118	for (c = 0; c < nc; c += BSIZE)
41888f16	119	if (bp = baddr(argdev, dbtofsb(bno)+(c>>BSHIFT))) {
29dd101b BJ	120	bp->b_flags \|= B_AGE; /* throw away */
	121	bp->b_flags &= ~B_DELWRI; /* cancel io */
	122	brelse(bp);
	123	bp = 0;
	124	}
	125	goto bad;
	126	}
	127
	128	/*
	129	* copy back arglist
	130	*/
	131
	132	ucp = USRSTACK - nc - NBPW;
	133	ap = ucp - naNBPW - 3NBPW;
	134	u.u_ar0[SP] = ap;
81263dba	135	(void) suword((caddr_t)ap, na-ne);
29dd101b BJ	136	nc = 0;
	137	for (;;) {
	138	ap += NBPW;
	139	if (na==ne) {
81263dba	140	(void) suword((caddr_t)ap, 0);
29dd101b BJ	141	ap += NBPW;
	142	}
	143	if (--na < 0)
	144	break;
81263dba	145	(void) suword((caddr_t)ap, ucp);
29dd101b BJ	146	do {
	147	if ((nc&BMASK) == 0) {
	148	if (bp)
	149	brelse(bp);
41888f16 BJ	150	bp = bread(argdev,
41888f16 BJ	151	(daddr_t)(dbtofsb(bno)+(nc>>BSHIFT)));
29dd101b BJ	152	bp->b_flags \|= B_AGE; /* throw away */
	153	bp->b_flags &= ~B_DELWRI; /* cancel io */
	154	cp = bp->b_un.b_addr;
	155	}
81263dba	156	(void) subyte((caddr_t)ucp++, (c = *cp++));
29dd101b BJ	157	nc++;
	158	} while(c&0377);
	159	}
81263dba BJ	160	(void) suword((caddr_t)ap, 0);
81263dba BJ	161	(void) suword((caddr_t)ucp, 0);
29dd101b BJ	162	setregs();
	163	bad:
	164	if (bp)
	165	brelse(bp);
	166	if (bno)
41888f16	167	mfree(argmap, ctod(clrnd((int) btoc(NCARGS))), bno);
29dd101b BJ	168	iput(ip);
	169	}
	170
	171	/*
	172	* Read in and set up memory for executed file.
	173	* Zero return is normal;
	174	* non-zero means only the text is being replaced
	175	*/
	176	getxfile(ip, nargc)
	177	register struct inode *ip;
	178	{
	179	register sep;
	180	register size_t ts, ds, ss;
3ca1542b	181	int overlay;
29dd101b BJ	182	int pagi = 0;
	183
	184	/*
	185	* read in first few bytes
	186	* of file for segment
	187	* sizes:
	188	* ux_mag = 407/410/411/405
	189	* 407 is plain executable
	190	* 410 is RO text
	191	* 411 is separated ID
	192	* 405 is overlaid text
	193	* 412 is demand paged plain executable (NOT IMPLEMENTED)
	194	* 413 is demand paged RO text
	195	*/
	196
	197	u.u_base = (caddr_t)&u.u_exdata;
	198	u.u_count = sizeof(u.u_exdata);
	199	u.u_offset = 0;
	200	u.u_segflg = 1;
	201	readi(ip);
	202	u.u_segflg = 0;
	203	if(u.u_error)
	204	goto bad;
	205	if (u.u_count!=0) {
	206	u.u_error = ENOEXEC;
	207	goto bad;
	208	}
	209	sep = 0;
	210	overlay = 0;
	211	switch (u.u_exdata.ux_mag) {
	212
	213	case 0405:
	214	overlay++;
	215	break;
	216
	217	case 0412:
	218	u.u_error = ENOEXEC;
	219	goto bad;
	220
	221	case 0407:
	222	u.u_exdata.ux_dsize += u.u_exdata.ux_tsize;
	223	u.u_exdata.ux_tsize = 0;
	224	break;
	225
	226	case 0413:
	227	pagi = SPAGI;
	228	/* fall into ... */
	229
	230	case 0410:
	231	if (u.u_exdata.ux_tsize == 0) {
	232	u.u_error = ENOEXEC;
	233	goto bad;
	234	}
	235	break;
	236
	237	case 0411:
	238	u.u_error = ENOEXEC;
	239	goto bad;
	240
	241	default:
	242	u.u_error = ENOEXEC;
	243	goto bad;
	244	}
	245	if(u.u_exdata.ux_tsize!=0 && (ip->i_flag&ITEXT)==0 && ip->i_count!=1) {
3ca1542b BJ	246	register struct file *fp;
	247
	248	for (fp = file; fp < &file[NFILE]; fp++)
	249	if (fp->f_inode == ip && (fp->f_flag&FWRITE)) {
	250	u.u_error = ETXTBSY;
	251	goto bad;
	252	}
29dd101b BJ	253	}
	254
	255	/*
	256	* find text and data sizes
	257	* try them out for possible
	258	* exceed of max sizes
	259	*/
	260
	261	ts = clrnd(btoc(u.u_exdata.ux_tsize));
	262	ds = clrnd(btoc((u.u_exdata.ux_dsize+u.u_exdata.ux_bsize)));
	263	ss = clrnd(SSIZE + btoc(nargc));
	264	if (overlay) {
8643403f BJ	265	if ((u.u_procp->p_flag & SPAGI) \|\|
8643403f BJ	266	u.u_sep==0 && ctos(ts) != ctos(u.u_tsize) \|\| nargc) {
29dd101b BJ	267	u.u_error = ENOMEM;
	268	goto bad;
	269	}
	270	ds = u.u_dsize;
	271	ss = u.u_ssize;
	272	sep = u.u_sep;
	273	xfree();
	274	xalloc(ip, pagi);
	275	u.u_ar0[PC] = u.u_exdata.ux_entloc + 2; /* skip over entry mask */
	276	} else {
	277	if (chksize(ts, ds, ss))
	278	goto bad;
	279	u.u_cdmap = zdmap;
	280	u.u_csmap = zdmap;
	281	if (swpexpand(ds, ss, &u.u_cdmap, &u.u_csmap) == NULL)
	282	goto bad;
	283
	284	/*
	285	* At this point, committed to the new image!
	286	* Release virtual memory resources of old process, and
	287	* initialize the virtual memory of the new process.
	288	* If we resulted from vfork(), instead wakeup our
	289	* parent who will set SVFDONE when he has taken back
	290	* our resources.
	291	*/
	292	u.u_prof.pr_scale = 0;
	293	if ((u.u_procp->p_flag & SVFORK) == 0)
	294	vrelvm();
	295	else {
	296	u.u_procp->p_flag &= ~SVFORK;
	297	u.u_procp->p_flag \|= SKEEP;
	298	wakeup((caddr_t)u.u_procp);
	299	while ((u.u_procp->p_flag & SVFDONE) == 0)
	300	sleep((caddr_t)u.u_procp, PZERO - 1);
	301	u.u_procp->p_flag &= ~(SVFDONE\|SKEEP);
	302	}
	303	u.u_procp->p_flag &= ~(SPAGI\|SANOM\|SUANOM);
	304	u.u_procp->p_flag \|= pagi;
	305	u.u_dmap = u.u_cdmap;
	306	u.u_smap = u.u_csmap;
	307	vgetvm(ts, ds, ss);
	308
	309	if (pagi == 0) {
	310	/*
	311	* Read in data segment.
	312	*/
	313	u.u_base = (char *)ctob(ts);
	314	u.u_offset = sizeof(u.u_exdata)+u.u_exdata.ux_tsize;
	315	u.u_count = u.u_exdata.ux_dsize;
	316	readi(ip);
	317	}
	318	xalloc(ip, pagi);
	319	if (pagi && u.u_procp->p_textp)
	320	vinifod((struct fpte *)dptopte(u.u_procp, 0),
	321	PG_FTEXT, u.u_procp->p_textp->x_iptr,
	322	1 + ts/CLSIZE, (int)btoc(u.u_exdata.ux_dsize));
	323
	324	/* THIS SHOULD BE DONE AT A LOWER LEVEL, IF AT ALL */
638352ae	325	mtpr(TBIA, 0);
29dd101b BJ	326
	327	/*
	328	* set SUID/SGID protections, if no tracing
	329	*/
	330	if ((u.u_procp->p_flag&STRC)==0) {
	331	if(ip->i_mode&ISUID)
	332	if(u.u_uid != 0) {
	333	u.u_uid = ip->i_uid;
	334	u.u_procp->p_uid = ip->i_uid;
	335	}
	336	if(ip->i_mode&ISGID)
	337	u.u_gid = ip->i_gid;
	338	} else
594ebedd	339	psignal(u.u_procp, SIGTRAP);
29dd101b BJ	340	}
	341	u.u_tsize = ts;
	342	u.u_dsize = ds;
	343	u.u_ssize = ss;
	344	u.u_sep = sep;
	345	bad:
	346	return(overlay);
	347	}
	348
	349	/*
	350	* Clear registers on exec
	351	*/
	352	setregs()
	353	{
594ebedd	354	register int (**rp)();
29dd101b	355	register i;
bdfe5b0f	356	long sigmask;
29dd101b	357
bdfe5b0f BJ	358	for(rp = &u.u_signal[0], sigmask = 1L; rp < &u.u_signal[NSIG];
	359	sigmask <<= 1, rp++) {
	360	switch (*rp) {
	361
	362	case SIG_IGN:
	363	case SIG_DFL:
	364	case SIG_HOLD:
	365	continue;
	366
	367	default:
	368	/*
99fa88a2	369	* Normal or deferring catch; revert to default.
bdfe5b0f	370	*/
99fa88a2 BJ	371	(void) spl6();
99fa88a2 BJ	372	*rp = SIG_DFL;
bdfe5b0f BJ	373	if ((int)*rp & 1)
	374	u.u_procp->p_siga0 \|= sigmask;
	375	else
	376	u.u_procp->p_siga1 &= ~sigmask;
	377	if ((int)*rp & 2)
	378	u.u_procp->p_siga1 \|= sigmask;
	379	else
	380	u.u_procp->p_siga1 &= ~sigmask;
99fa88a2	381	(void) spl0();
bdfe5b0f BJ	382	continue;
	383	}
	384	}
29dd101b BJ	385	/*
	386	for(rp = &u.u_ar0[0]; rp < &u.u_ar0[16];)
	387	*rp++ = 0;
	388	*/
	389	u.u_ar0[PC] = u.u_exdata.ux_entloc + 2; /* skip over entry mask */
	390	for(i=0; i<NOFILE; i++) {
	391	if (u.u_pofile[i]&EXCLOSE) {
	392	closef(u.u_ofile[i]);
	393	u.u_ofile[i] = NULL;
bdfe5b0f	394	u.u_pofile[i] &= ~EXCLOSE;
29dd101b	395	}
29dd101b BJ	396	}
	397	/*
	398	* Remember file name for accounting.
	399	*/
	400	u.u_acflag &= ~AFORK;
	401	bcopy((caddr_t)u.u_dbuf, (caddr_t)u.u_comm, DIRSIZ);
	402	}
	403
	404	/*
	405	* exit system call:
	406	* pass back caller's arg
	407	*/
	408	rexit()
	409	{
	410	register struct a {
	411	int rval;
	412	} *uap;
	413
	414	uap = (struct a *)u.u_ap;
	415	exit((uap->rval & 0377) << 8);
	416	}
	417
	418	/*
	419	* Release resources.
	420	* Save u. area for parent to look at.
	421	* Enter zombie state.
	422	* Wake up parent and init processes,
	423	* and dispose of children.
	424	*/
	425	exit(rv)
	426	{
	427	register int i;
	428	register struct proc p, q;
	429	register struct file *f;
	430	register int x;
	431
	432	#ifdef PGINPROF
	433	vmsizmon();
	434	#endif
	435	p = u.u_procp;
	436	p->p_flag &= ~(STRC\|SULOCK);
	437	p->p_flag \|= SWEXIT;
	438	p->p_clktim = 0;
bdfe5b0f BJ	439	(void) spl6();
	440	if ((int)SIG_IGN & 1)
	441	p->p_siga0 = ~0;
	442	else
	443	p->p_siga0 = 0;
	444	if ((int)SIG_IGN & 2)
	445	p->p_siga1 = ~0;
	446	else
99fa88a2	447	p->p_siga1 = 0;
bdfe5b0f	448	(void) spl0();
29dd101b BJ	449	p->p_aveflt = 0;
29dd101b BJ	450	for(i=0; i<NSIG; i++)
594ebedd	451	u.u_signal[i] = SIG_IGN;
29dd101b BJ	452	/*
	453	* Release virtual memory. If we resulted from
	454	* a vfork(), instead give the resources back to
	455	* the parent.
	456	*/
	457	if ((p->p_flag & SVFORK) == 0)
	458	vrelvm();
	459	else {
	460	p->p_flag &= ~SVFORK;
	461	wakeup((caddr_t)p);
	462	while ((p->p_flag & SVFDONE) == 0)
	463	sleep((caddr_t)p, PZERO - 1);
	464	p->p_flag &= ~SVFDONE;
	465	}
	466	for(i=0; i<NOFILE; i++) {
	467	f = u.u_ofile[i];
	468	u.u_ofile[i] = NULL;
	469	closef(f);
	470	}
	471	plock(u.u_cdir);
	472	iput(u.u_cdir);
	473	if (u.u_rdir) {
	474	plock(u.u_rdir);
	475	iput(u.u_rdir);
	476	}
054016e1	477	u.u_limit[LIM_FSIZE] = INFINITY;
29dd101b BJ	478	acct();
	479	vrelpt(u.u_procp);
	480	vrelu(u.u_procp, 0);
	481	multprog--;
41888f16 BJ	482	/* spl7(); /* clock will get mad because of overlaying */
41888f16 BJ	483	noproc = 1;
29dd101b BJ	484	p->p_stat = SZOMB;
	485	i = PIDHASH(p->p_pid);
	486	x = p - proc;
	487	if (pidhash[i] == x)
	488	pidhash[i] = p->p_idhash;
	489	else {
	490	for (i = pidhash[i]; i != 0; i = proc[i].p_idhash)
	491	if (proc[i].p_idhash == x) {
	492	proc[i].p_idhash = p->p_idhash;
	493	goto done;
	494	}
	495	panic("exit");
	496	}
	497	done:
	498	((struct xproc )p)->xp_xstat = rv; / overlay */
	499	((struct xproc )p)->xp_vm = u.u_vm; / overlay */
	500	vmsadd(&((struct xproc *)p)->xp_vm, &u.u_cvm);
	501	for(q = &proc[0]; q < &proc[NPROC]; q++)
bdfe5b0f BJ	502	if(q->p_pptr == p) {
bdfe5b0f BJ	503	q->p_pptr = &proc[1];
29dd101b	504	q->p_ppid = 1;
bdfe5b0f BJ	505	wakeup((caddr_t)&proc[1]);
bdfe5b0f BJ	506	/*
0dde1c43	507	* Traced processes are killed
bdfe5b0f	508	* since their existence means someone is screwing up.
62bac59f	509	* Stopped processes are sent a hangup and a continue.
0dde1c43 BJ	510	* This is designed to be ``safe'' for setuid
	511	* processes since they must be willing to tolerate
	512	* hangups anyways.
bdfe5b0f	513	*/
0dde1c43	514	if (q->p_flag&STRC) {
bdfe5b0f BJ	515	q->p_flag &= ~STRC;
bdfe5b0f BJ	516	psignal(q, SIGKILL);
0dde1c43 BJ	517	} else if (q->p_stat == SSTOP) {
	518	psignal(q, SIGHUP);
	519	psignal(q, SIGCONT);
bdfe5b0f	520	}
8643403f BJ	521	/*
8643403f BJ	522	* Protect this process from future
62bac59f BJ	523	* tty signals, clear TSTP/TTIN/TTOU if pending,
62bac59f BJ	524	* and set SDETACH bit on procs.
8643403f	525	*/
41888f16	526	spgrp(q, -1);
29dd101b	527	}
bdfe5b0f BJ	528	wakeup((caddr_t)p->p_pptr);
bdfe5b0f BJ	529	psignal(p->p_pptr, SIGCHLD);
29dd101b BJ	530	swtch();
	531	}
	532
	533	wait()
	534	{
bdfe5b0f BJ	535	struct vtimes vm;
bdfe5b0f BJ	536	struct vtimes *vp;
29dd101b	537
bdfe5b0f BJ	538	if ((u.u_ar0[PS] & PSL_ALLCC) != PSL_ALLCC) {
	539	wait1(0, (struct vtimes *)0);
	540	return;
	541	}
	542	vp = (struct vtimes *)u.u_ar0[R1];
	543	wait1(u.u_ar0[R0], &vm);
	544	if (u.u_error)
	545	return;
	546	(void) copyout((caddr_t)&vm, (caddr_t)vp, sizeof (struct vtimes));
29dd101b BJ	547	}
	548
	549	/*
	550	* Wait system call.
	551	* Search for a terminated (zombie) child,
	552	* finally lay it to rest, and collect its status.
	553	* Look also for stopped (traced) children,
	554	* and pass back status from them.
	555	*/
bdfe5b0f BJ	556	wait1(options, vp)
bdfe5b0f BJ	557	register options;
29dd101b BJ	558	struct vtimes *vp;
	559	{
	560	register f;
	561	register struct proc *p;
	562
	563	f = 0;
29dd101b BJ	564	loop:
29dd101b BJ	565	for(p = &proc[0]; p < &proc[NPROC]; p++)
bdfe5b0f	566	if(p->p_pptr == u.u_procp) {
29dd101b BJ	567	f++;
	568	if(p->p_stat == SZOMB) {
	569	u.u_r.r_val1 = p->p_pid;
	570	u.u_r.r_val2 = ((struct xproc *)p)->xp_xstat;
	571	((struct xproc *)p)->xp_xstat = 0;
	572	if (vp)
	573	vp = ((struct xproc )p)->xp_vm;
	574	vmsadd(&u.u_cvm, &((struct xproc *)p)->xp_vm);
	575	((struct xproc *)p)->xp_vm = zvms;
	576	p->p_stat = NULL;
	577	p->p_pid = 0;
	578	p->p_ppid = 0;
bdfe5b0f	579	p->p_pptr = 0;
29dd101b	580	p->p_sig = 0;
bdfe5b0f BJ	581	p->p_siga0 = 0;
bdfe5b0f BJ	582	p->p_siga1 = 0;
29dd101b BJ	583	p->p_pgrp = 0;
	584	p->p_flag = 0;
	585	p->p_wchan = 0;
bdfe5b0f	586	p->p_cursig = 0;
29dd101b BJ	587	return;
29dd101b BJ	588	}
bdfe5b0f BJ	589	if (p->p_stat == SSTOP && (p->p_flag&SWTED)==0 &&
	590	(p->p_flag&STRC \|\| options&WUNTRACED)) {
	591	p->p_flag \|= SWTED;
	592	u.u_r.r_val1 = p->p_pid;
	593	u.u_r.r_val2 = (p->p_cursig<<8) \| WSTOPPED;
	594	return;
29dd101b BJ	595	}
29dd101b BJ	596	}
bdfe5b0f BJ	597	if (f==0) {
	598	u.u_error = ECHILD;
	599	return;
	600	}
	601	if (options&WNOHANG) {
	602	u.u_r.r_val1 = 0;
	603	return;
	604	}
99fa88a2	605	/*
bdfe5b0f BJ	606	if (setjmp(u.u_qsav)) {
	607	u.u_eosys = RESTARTSYS;
	608	return;
29dd101b	609	}
99fa88a2	610	*/
bdfe5b0f BJ	611	sleep((caddr_t)u.u_procp, PWAIT);
bdfe5b0f BJ	612	goto loop;
29dd101b BJ	613	}
	614
	615	/*
	616	* fork system call.
	617	*/
	618	fork()
	619	{
	620
	621	u.u_cdmap = zdmap;
	622	u.u_csmap = zdmap;
	623	if (swpexpand(u.u_dsize, u.u_ssize, &u.u_cdmap, &u.u_csmap) == 0) {
	624	u.u_r.r_val2 = 0;
	625	return;
	626	}
	627	fork1(0);
	628	}
	629
	630	fork1(isvfork)
	631	{
	632	register struct proc p1, p2;
	633	register a;
	634
	635	a = 0;
	636	p2 = NULL;
	637	for(p1 = &proc[0]; p1 < &proc[NPROC]; p1++) {
	638	if (p1->p_stat==NULL && p2==NULL)
	639	p2 = p1;
	640	else {
	641	if (p1->p_uid==u.u_uid && p1->p_stat!=NULL)
	642	a++;
	643	}
	644	}
	645	/*
	646	* Disallow if
	647	* No processes at all;
	648	* not su and too many procs owned; or
	649	* not su and would take last slot.
	650	*/
	651	if (p2==NULL \|\| (u.u_uid!=0 && (p2==&proc[NPROC-1] \|\| a>MAXUPRC))) {
	652	u.u_error = EAGAIN;
	653	if (!isvfork) {
81263dba BJ	654	(void) vsexpand(0, &u.u_cdmap, 1);
81263dba BJ	655	(void) vsexpand(0, &u.u_csmap, 1);
29dd101b BJ	656	}
	657	goto out;
	658	}
	659	p1 = u.u_procp;
	660	if(newproc(isvfork)) {
	661	u.u_r.r_val1 = p1->p_pid;
	662	u.u_r.r_val2 = 1; /* child */
	663	u.u_start = time;
	664	u.u_acflag = AFORK;
	665	return;
	666	}
	667	u.u_r.r_val1 = p2->p_pid;
	668
	669	out:
	670	u.u_r.r_val2 = 0;
	671	}
	672
	673	/*
	674	* break system call.
	675	* -- bad planning: "break" is a dirty word in C.
	676	*/
	677	sbreak()
	678	{
	679	struct a {
	680	char *nsiz;
	681	};
	682	register int n, d;
	683
	684	/*
	685	* set n to new data size
	686	* set d to new-old
	687	*/
	688
	689	n = btoc(((struct a *)u.u_ap)->nsiz);
	690	if (!u.u_sep)
	691	n -= ctos(u.u_tsize) * stoc(1);
	692	if (n < 0)
	693	n = 0;
	694	d = clrnd(n - u.u_dsize);
5290ec92	695	if (ctob(u.u_dsize+d) > u.u_limit[LIM_DATA]) {
054016e1 BJ	696	u.u_error = ENOMEM;
	697	return;
	698	}
29dd101b BJ	699	if (chksize(u.u_tsize, u.u_dsize+d, u.u_ssize))
	700	return;
	701	if (swpexpand(u.u_dsize+d, u.u_ssize, &u.u_dmap, &u.u_smap)==0)
	702	return;
	703	expand(d, P0BR);
	704	}