[unix-history] / usr / src / sys / kern / sys_generic.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.
 *
 *	@(#)sys_generic.c	7.1 (Berkeley) %G%
 */

#include "param.h"
#include "systm.h"
#include "dir.h"
#include "user.h"
#include "ioctl.h"
#include "file.h"
#include "proc.h"
#include "uio.h"
#include "kernel.h"
#include "stat.h"

/*
 * Read system call.
 */
read()
{
	register struct a {
		int	fdes;
		char	*cbuf;
		unsigned count;
	} *uap = (struct a *)u.u_ap;
	struct uio auio;
	struct iovec aiov;

	aiov.iov_base = (caddr_t)uap->cbuf;
	aiov.iov_len = uap->count;
	auio.uio_iov = &aiov;
	auio.uio_iovcnt = 1;
	rwuio(&auio, UIO_READ);
}

readv()
{
	register struct a {
		int	fdes;
		struct	iovec *iovp;
		unsigned iovcnt;
	} *uap = (struct a *)u.u_ap;
	struct uio auio;
	struct iovec aiov[16];		/* XXX */

	if (uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
		u.u_error = EINVAL;
		return;
	}
	auio.uio_iov = aiov;
	auio.uio_iovcnt = uap->iovcnt;
	u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
	    uap->iovcnt * sizeof (struct iovec));
	if (u.u_error)
		return;
	rwuio(&auio, UIO_READ);
}

/*
 * Write system call
 */
write()
{
	register struct a {
		int	fdes;
		char	*cbuf;
		unsigned count;
	} *uap = (struct a *)u.u_ap;
	struct uio auio;
	struct iovec aiov;

	auio.uio_iov = &aiov;
	auio.uio_iovcnt = 1;
	aiov.iov_base = uap->cbuf;
	aiov.iov_len = uap->count;
	rwuio(&auio, UIO_WRITE);
}

writev()
{
	register struct a {
		int	fdes;
		struct	iovec *iovp;
		unsigned iovcnt;
	} *uap = (struct a *)u.u_ap;
	struct uio auio;
	struct iovec aiov[16];		/* XXX */

	if (uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
		u.u_error = EINVAL;
		return;
	}
	auio.uio_iov = aiov;
	auio.uio_iovcnt = uap->iovcnt;
	u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
	    uap->iovcnt * sizeof (struct iovec));
	if (u.u_error)
		return;
	rwuio(&auio, UIO_WRITE);
}

rwuio(uio, rw)
	register struct uio *uio;
	enum uio_rw rw;
{
	struct a {
		int	fdes;
	};
	register struct file *fp;
	register struct iovec *iov;
	int i, count;

	GETF(fp, ((struct a *)u.u_ap)->fdes);
	if ((fp->f_flag&(rw==UIO_READ ? FREAD : FWRITE)) == 0) {
		u.u_error = EBADF;
		return;
	}
	uio->uio_resid = 0;
	uio->uio_segflg = UIO_USERSPACE;
	iov = uio->uio_iov;
	for (i = 0; i < uio->uio_iovcnt; i++) {
		if (iov->iov_len < 0) {
			u.u_error = EINVAL;
			return;
		}
		uio->uio_resid += iov->iov_len;
		if (uio->uio_resid < 0) {
			u.u_error = EINVAL;
			return;
		}
		iov++;
	}
	count = uio->uio_resid;
	uio->uio_offset = fp->f_offset;
	if (setjmp(&u.u_qsave)) {
		if (uio->uio_resid == count) {
			if ((u.u_sigintr & sigmask(u.u_procp->p_cursig)) != 0)
				u.u_error = EINTR;
			else
				u.u_eosys = RESTARTSYS;
		}
	} else
		u.u_error = (*fp->f_ops->fo_rw)(fp, rw, uio);
	u.u_r.r_val1 = count - uio->uio_resid;
	fp->f_offset += u.u_r.r_val1;
}

/*
 * Ioctl system call
 */
ioctl()
{
	register struct file *fp;
	struct a {
		int	fdes;
		int	cmd;
		caddr_t	cmarg;
	} *uap;
	register int com;
	register u_int size;
	char data[IOCPARM_MASK+1];

	uap = (struct a *)u.u_ap;
	GETF(fp, uap->fdes);
	if ((fp->f_flag & (FREAD|FWRITE)) == 0) {
		u.u_error = EBADF;
		return;
	}
	com = uap->cmd;

#if defined(vax) && defined(COMPAT)
	/*
	 * Map old style ioctl's into new for the
	 * sake of backwards compatibility (sigh).
	 */
	if ((com&~0xffff) == 0) {
		com = mapioctl(com);
		if (com == 0) {
			u.u_error = EINVAL;
			return;
		}
	}
#endif
	if (com == FIOCLEX) {
		u.u_pofile[uap->fdes] |= UF_EXCLOSE;
		return;
	}
	if (com == FIONCLEX) {
		u.u_pofile[uap->fdes] &= ~UF_EXCLOSE;
		return;
	}

	/*
	 * Interpret high order word to find
	 * amount of data to be copied to/from the
	 * user's address space.
	 */
	size = (com &~ (IOC_INOUT|IOC_VOID)) >> 16;
	if (size > sizeof (data)) {
		u.u_error = EFAULT;
		return;
	}
	if (com&IOC_IN) {
		if (size) {
			u.u_error =
			    copyin(uap->cmarg, (caddr_t)data, (u_int)size);
			if (u.u_error)
				return;
		} else
			*(caddr_t *)data = uap->cmarg;
	} else if ((com&IOC_OUT) && size)
		/*
		 * Zero the buffer on the stack so the user
		 * always gets back something deterministic.
		 */
		bzero((caddr_t)data, size);
	else if (com&IOC_VOID)
		*(caddr_t *)data = uap->cmarg;

	switch (com) {

	case FIONBIO:
		u.u_error = fset(fp, FNDELAY, *(int *)data);
		return;

	case FIOASYNC:
		u.u_error = fset(fp, FASYNC, *(int *)data);
		return;

	case FIOSETOWN:
		u.u_error = fsetown(fp, *(int *)data);
		return;

	case FIOGETOWN:
		u.u_error = fgetown(fp, (int *)data);
		return;
	}
	u.u_error = (*fp->f_ops->fo_ioctl)(fp, com, data);
	/*
	 * Copy any data to user, size was
	 * already set and checked above.
	 */
	if (u.u_error == 0 && (com&IOC_OUT) && size)
		u.u_error = copyout(data, uap->cmarg, (u_int)size);
}

int	unselect();
int	nselcoll;

/*
 * Select system call.
 */
select()
{
	register struct uap  {
		int	nd;
		fd_set	*in, *ou, *ex;
		struct	timeval *tv;
	} *uap = (struct uap *)u.u_ap;
	fd_set ibits[3], obits[3];
	struct timeval atv;
	int s, ncoll, ni;
	label_t lqsave;

	bzero((caddr_t)ibits, sizeof(ibits));
	bzero((caddr_t)obits, sizeof(obits));
	if (uap->nd > NOFILE)
		uap->nd = NOFILE;	/* forgiving, if slightly wrong */
	ni = howmany(uap->nd, NFDBITS);

#define	getbits(name, x) \
	if (uap->name) { \
		u.u_error = copyin((caddr_t)uap->name, (caddr_t)&ibits[x], \
		    (unsigned)(ni * sizeof(fd_mask))); \
		if (u.u_error) \
			goto done; \
	}
	getbits(in, 0);
	getbits(ou, 1);
	getbits(ex, 2);
#undef	getbits

	if (uap->tv) {
		u.u_error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
			sizeof (atv));
		if (u.u_error)
			goto done;
		if (itimerfix(&atv)) {
			u.u_error = EINVAL;
			goto done;
		}
		s = splhigh(); timevaladd(&atv, &time); splx(s);
	}
retry:
	ncoll = nselcoll;
	u.u_procp->p_flag |= SSEL;
	u.u_r.r_val1 = selscan(ibits, obits, uap->nd);
	if (u.u_error || u.u_r.r_val1)
		goto done;
	s = splhigh();
	/* this should be timercmp(&time, &atv, >=) */
	if (uap->tv && (time.tv_sec > atv.tv_sec ||
	    time.tv_sec == atv.tv_sec && time.tv_usec >= atv.tv_usec)) {
		splx(s);
		goto done;
	}
	if ((u.u_procp->p_flag & SSEL) == 0 || nselcoll != ncoll) {
		u.u_procp->p_flag &= ~SSEL;
		splx(s);
		goto retry;
	}
	u.u_procp->p_flag &= ~SSEL;
	if (uap->tv) {
		lqsave = u.u_qsave;
		if (setjmp(&u.u_qsave)) {
			untimeout(unselect, (caddr_t)u.u_procp);
			u.u_error = EINTR;
			splx(s);
			goto done;
		}
		timeout(unselect, (caddr_t)u.u_procp, hzto(&atv));
	}
	sleep((caddr_t)&selwait, PZERO+1);
	if (uap->tv) {
		u.u_qsave = lqsave;
		untimeout(unselect, (caddr_t)u.u_procp);
	}
	splx(s);
	goto retry;
done:
#define	putbits(name, x) \
	if (uap->name) { \
		int error = copyout((caddr_t)&obits[x], (caddr_t)uap->name, \
		    (unsigned)(ni * sizeof(fd_mask))); \
		if (error) \
			u.u_error = error; \
	}
	if (u.u_error == 0) {
		putbits(in, 0);
		putbits(ou, 1);
		putbits(ex, 2);
#undef putbits
	}
}

unselect(p)
	register struct proc *p;
{
	register int s = splhigh();

	switch (p->p_stat) {

	case SSLEEP:
		setrun(p);
		break;

	case SSTOP:
		unsleep(p);
		break;
	}
	splx(s);
}

selscan(ibits, obits, nfd)
	fd_set *ibits, *obits;
{
	register int which, i, j;
	register fd_mask bits;
	int flag;
	struct file *fp;
	int n = 0;

	for (which = 0; which < 3; which++) {
		switch (which) {

		case 0:
			flag = FREAD; break;

		case 1:
			flag = FWRITE; break;

		case 2:
			flag = 0; break;
		}
		for (i = 0; i < nfd; i += NFDBITS) {
			bits = ibits[which].fds_bits[i/NFDBITS];
			while ((j = ffs(bits)) && i + --j < nfd) {
				bits &= ~(1 << j);
				fp = u.u_ofile[i + j];
				if (fp == NULL) {
					u.u_error = EBADF;
					break;
				}
				if ((*fp->f_ops->fo_select)(fp, flag)) {
					FD_SET(i + j, &obits[which]);
					n++;
				}
			}
		}
	}
	return (n);
}

/*ARGSUSED*/
seltrue(dev, flag)
	dev_t dev;
	int flag;
{

	return (1);
}

selwakeup(p, coll)
	register struct proc *p;
	int coll;
{

	if (coll) {
		nselcoll++;
		wakeup((caddr_t)&selwait);
	}
	if (p) {
		int s = splhigh();
		if (p->p_wchan == (caddr_t)&selwait) {
			if (p->p_stat == SSLEEP)
				setrun(p);
			else
				unsleep(p);
		} else if (p->p_flag & SSEL)
			p->p_flag &= ~SSEL;
		splx(s);
	}
}
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	*
0880b18e	6	* @(#)sys_generic.c 7.1 (Berkeley) %G%
da7c5cc6	7	*/
ffe28cfe	8
94368568 JB	9	#include "param.h"
	10	#include "systm.h"
	11	#include "dir.h"
	12	#include "user.h"
	13	#include "ioctl.h"
	14	#include "file.h"
	15	#include "proc.h"
	16	#include "uio.h"
	17	#include "kernel.h"
	18	#include "stat.h"
ffe28cfe BJ	19
	20	/*
	21	* Read system call.
	22	*/
	23	read()
	24	{
ffe28cfe BJ	25	register struct a {
	26	int fdes;
	27	char *cbuf;
	28	unsigned count;
b9429893	29	} uap = (struct a )u.u_ap;
32a43ee2 BJ	30	struct uio auio;
32a43ee2 BJ	31	struct iovec aiov;
ffe28cfe	32
32a43ee2 BJ	33	aiov.iov_base = (caddr_t)uap->cbuf;
	34	aiov.iov_len = uap->count;
	35	auio.uio_iov = &aiov;
	36	auio.uio_iovcnt = 1;
b9429893 BJ	37	rwuio(&auio, UIO_READ);
	38	}
	39
	40	readv()
	41	{
	42	register struct a {
	43	int fdes;
	44	struct iovec *iovp;
31286ce2	45	unsigned iovcnt;
b9429893 BJ	46	} uap = (struct a )u.u_ap;
	47	struct uio auio;
	48	struct iovec aiov[16]; /* XXX */
	49
31286ce2	50	if (uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
b9429893 BJ	51	u.u_error = EINVAL;
	52	return;
	53	}
	54	auio.uio_iov = aiov;
	55	auio.uio_iovcnt = uap->iovcnt;
127f7d76	56	u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
31286ce2	57	uap->iovcnt * sizeof (struct iovec));
127f7d76	58	if (u.u_error)
b9429893	59	return;
b9429893	60	rwuio(&auio, UIO_READ);
ffe28cfe BJ	61	}
	62
	63	/*
	64	* Write system call
	65	*/
	66	write()
	67	{
ffe28cfe BJ	68	register struct a {
	69	int fdes;
	70	char *cbuf;
31286ce2	71	unsigned count;
b9429893 BJ	72	} uap = (struct a )u.u_ap;
	73	struct uio auio;
	74	struct iovec aiov;
ffe28cfe	75
b9429893 BJ	76	auio.uio_iov = &aiov;
	77	auio.uio_iovcnt = 1;
	78	aiov.iov_base = uap->cbuf;
	79	aiov.iov_len = uap->count;
	80	rwuio(&auio, UIO_WRITE);
	81	}
	82
	83	writev()
	84	{
	85	register struct a {
	86	int fdes;
	87	struct iovec *iovp;
31286ce2	88	unsigned iovcnt;
b9429893 BJ	89	} uap = (struct a )u.u_ap;
	90	struct uio auio;
	91	struct iovec aiov[16]; /* XXX */
	92
31286ce2	93	if (uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
ffe28cfe BJ	94	u.u_error = EINVAL;
	95	return;
	96	}
b9429893 BJ	97	auio.uio_iov = aiov;
b9429893 BJ	98	auio.uio_iovcnt = uap->iovcnt;
127f7d76	99	u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
31286ce2	100	uap->iovcnt * sizeof (struct iovec));
127f7d76	101	if (u.u_error)
b9429893	102	return;
b9429893 BJ	103	rwuio(&auio, UIO_WRITE);
	104	}
	105
	106	rwuio(uio, rw)
	107	register struct uio *uio;
	108	enum uio_rw rw;
	109	{
	110	struct a {
	111	int fdes;
	112	};
	113	register struct file *fp;
	114	register struct iovec *iov;
b9429893 BJ	115	int i, count;
	116
	117	GETF(fp, ((struct a *)u.u_ap)->fdes);
	118	if ((fp->f_flag&(rw==UIO_READ ? FREAD : FWRITE)) == 0) {
ffe28cfe BJ	119	u.u_error = EBADF;
	120	return;
	121	}
b9429893	122	uio->uio_resid = 0;
c41770c0	123	uio->uio_segflg = UIO_USERSPACE;
b9429893 BJ	124	iov = uio->uio_iov;
	125	for (i = 0; i < uio->uio_iovcnt; i++) {
	126	if (iov->iov_len < 0) {
	127	u.u_error = EINVAL;
	128	return;
	129	}
	130	uio->uio_resid += iov->iov_len;
	131	if (uio->uio_resid < 0) {
	132	u.u_error = EINVAL;
	133	return;
	134	}
2a0114a8	135	iov++;
b9429893 BJ	136	}
b9429893 BJ	137	count = uio->uio_resid;
88a7a62a	138	uio->uio_offset = fp->f_offset;
fe7f81f4 KM	139	if (setjmp(&u.u_qsave)) {
fe7f81f4 KM	140	if (uio->uio_resid == count) {
9f49ba41	141	if ((u.u_sigintr & sigmask(u.u_procp->p_cursig)) != 0)
fe7f81f4 KM	142	u.u_error = EINTR;
	143	else
	144	u.u_eosys = RESTARTSYS;
	145	}
b9429893	146	} else
88a7a62a SL	147	u.u_error = (*fp->f_ops->fo_rw)(fp, rw, uio);
	148	u.u_r.r_val1 = count - uio->uio_resid;
	149	fp->f_offset += u.u_r.r_val1;
4147b3f6	150	}
ffe28cfe BJ	151
	152	/*
	153	* Ioctl system call
ffe28cfe BJ	154	*/
	155	ioctl()
	156	{
	157	register struct file *fp;
4b72e2f9	158	struct a {
ffe28cfe BJ	159	int fdes;
	160	int cmd;
	161	caddr_t cmarg;
	162	} *uap;
b9429893 BJ	163	register int com;
b9429893 BJ	164	register u_int size;
4b72e2f9	165	char data[IOCPARM_MASK+1];
ffe28cfe BJ	166
ffe28cfe BJ	167	uap = (struct a *)u.u_ap;
21e0a474	168	GETF(fp, uap->fdes);
ffe28cfe BJ	169	if ((fp->f_flag & (FREAD\|FWRITE)) == 0) {
	170	u.u_error = EBADF;
	171	return;
	172	}
4b72e2f9 SL	173	com = uap->cmd;
4b72e2f9 SL	174
75a02b8d	175	#if defined(vax) && defined(COMPAT)
4b72e2f9 SL	176	/*
	177	* Map old style ioctl's into new for the
	178	* sake of backwards compatibility (sigh).
	179	*/
	180	if ((com&~0xffff) == 0) {
	181	com = mapioctl(com);
	182	if (com == 0) {
	183	u.u_error = EINVAL;
	184	return;
	185	}
	186	}
	187	#endif
	188	if (com == FIOCLEX) {
3650c37d	189	u.u_pofile[uap->fdes] \|= UF_EXCLOSE;
ffe28cfe BJ	190	return;
ffe28cfe BJ	191	}
4b72e2f9	192	if (com == FIONCLEX) {
3650c37d	193	u.u_pofile[uap->fdes] &= ~UF_EXCLOSE;
ffe28cfe BJ	194	return;
ffe28cfe BJ	195	}
4b72e2f9 SL	196
	197	/*
	198	* Interpret high order word to find
	199	* amount of data to be copied to/from the
	200	* user's address space.
4b72e2f9 SL	201	*/
	202	size = (com &~ (IOC_INOUT\|IOC_VOID)) >> 16;
	203	if (size > sizeof (data)) {
	204	u.u_error = EFAULT;
ffe28cfe BJ	205	return;
ffe28cfe BJ	206	}
471f17ed SL	207	if (com&IOC_IN) {
	208	if (size) {
	209	u.u_error =
	210	copyin(uap->cmarg, (caddr_t)data, (u_int)size);
	211	if (u.u_error)
	212	return;
	213	} else
	214	(caddr_t )data = uap->cmarg;
	215	} else if ((com&IOC_OUT) && size)
	216	/*
	217	* Zero the buffer on the stack so the user
	218	* always gets back something deterministic.
	219	*/
4b72e2f9	220	bzero((caddr_t)data, size);
a76b60f6 SL	221	else if (com&IOC_VOID)
a76b60f6 SL	222	(caddr_t )data = uap->cmarg;
4b72e2f9	223
88a7a62a SL	224	switch (com) {
	225
	226	case FIONBIO:
	227	u.u_error = fset(fp, FNDELAY, (int )data);
	228	return;
	229
	230	case FIOASYNC:
	231	u.u_error = fset(fp, FASYNC, (int )data);
	232	return;
	233
	234	case FIOSETOWN:
	235	u.u_error = fsetown(fp, (int )data);
	236	return;
4b72e2f9	237
88a7a62a SL	238	case FIOGETOWN:
	239	u.u_error = fgetown(fp, (int *)data);
	240	return;
	241	}
	242	u.u_error = (*fp->f_ops->fo_ioctl)(fp, com, data);
4b72e2f9 SL	243	/*
	244	* Copy any data to user, size was
	245	* already set and checked above.
	246	*/
127f7d76 SL	247	if (u.u_error == 0 && (com&IOC_OUT) && size)
127f7d76 SL	248	u.u_error = copyout(data, uap->cmarg, (u_int)size);
ffe28cfe BJ	249	}
ffe28cfe BJ	250
88a7a62a SL	251	int unselect();
88a7a62a SL	252	int nselcoll;
d441e5bc	253
ffe28cfe	254	/*
88a7a62a	255	* Select system call.
ffe28cfe	256	*/
88a7a62a SL	257	select()
	258	{
	259	register struct uap {
	260	int nd;
b8e71e77	261	fd_set in, ou, *ex;
88a7a62a SL	262	struct timeval *tv;
88a7a62a SL	263	} uap = (struct uap )u.u_ap;
b8e71e77	264	fd_set ibits[3], obits[3];
88a7a62a	265	struct timeval atv;
d441e5bc	266	int s, ncoll, ni;
88a7a62a SL	267	label_t lqsave;
88a7a62a SL	268
01b0e233 MK	269	bzero((caddr_t)ibits, sizeof(ibits));
01b0e233 MK	270	bzero((caddr_t)obits, sizeof(obits));
88a7a62a SL	271	if (uap->nd > NOFILE)
88a7a62a SL	272	uap->nd = NOFILE; /* forgiving, if slightly wrong */
b8e71e77	273	ni = howmany(uap->nd, NFDBITS);
88a7a62a SL	274
	275	#define getbits(name, x) \
	276	if (uap->name) { \
b8e71e77	277	u.u_error = copyin((caddr_t)uap->name, (caddr_t)&ibits[x], \
01b0e233	278	(unsigned)(ni * sizeof(fd_mask))); \
88a7a62a SL	279	if (u.u_error) \
88a7a62a SL	280	goto done; \
d441e5bc	281	}
88a7a62a SL	282	getbits(in, 0);
	283	getbits(ou, 1);
	284	getbits(ex, 2);
	285	#undef getbits
	286
	287	if (uap->tv) {
	288	u.u_error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
	289	sizeof (atv));
	290	if (u.u_error)
	291	goto done;
	292	if (itimerfix(&atv)) {
	293	u.u_error = EINVAL;
	294	goto done;
	295	}
c4e1f1e5	296	s = splhigh(); timevaladd(&atv, &time); splx(s);
88a7a62a SL	297	}
	298	retry:
	299	ncoll = nselcoll;
	300	u.u_procp->p_flag \|= SSEL;
d441e5bc	301	u.u_r.r_val1 = selscan(ibits, obits, uap->nd);
88a7a62a SL	302	if (u.u_error \|\| u.u_r.r_val1)
88a7a62a SL	303	goto done;
c4e1f1e5	304	s = splhigh();
e394e134 SL	305	/* this should be timercmp(&time, &atv, >=) */
	306	if (uap->tv && (time.tv_sec > atv.tv_sec \|\|
	307	time.tv_sec == atv.tv_sec && time.tv_usec >= atv.tv_usec)) {
88a7a62a SL	308	splx(s);
	309	goto done;
	310	}
	311	if ((u.u_procp->p_flag & SSEL) == 0 \|\| nselcoll != ncoll) {
	312	u.u_procp->p_flag &= ~SSEL;
	313	splx(s);
	314	goto retry;
	315	}
	316	u.u_procp->p_flag &= ~SSEL;
	317	if (uap->tv) {
	318	lqsave = u.u_qsave;
	319	if (setjmp(&u.u_qsave)) {
	320	untimeout(unselect, (caddr_t)u.u_procp);
	321	u.u_error = EINTR;
	322	splx(s);
	323	goto done;
	324	}
	325	timeout(unselect, (caddr_t)u.u_procp, hzto(&atv));
	326	}
	327	sleep((caddr_t)&selwait, PZERO+1);
	328	if (uap->tv) {
	329	u.u_qsave = lqsave;
	330	untimeout(unselect, (caddr_t)u.u_procp);
	331	}
	332	splx(s);
	333	goto retry;
	334	done:
	335	#define putbits(name, x) \
	336	if (uap->name) { \
b8e71e77	337	int error = copyout((caddr_t)&obits[x], (caddr_t)uap->name, \
01b0e233	338	(unsigned)(ni * sizeof(fd_mask))); \
88a7a62a SL	339	if (error) \
	340	u.u_error = error; \
	341	}
87a3ba07	342	if (u.u_error == 0) {
79f403fc MK	343	putbits(in, 0);
	344	putbits(ou, 1);
	345	putbits(ex, 2);
88a7a62a	346	#undef putbits
79f403fc	347	}
88a7a62a SL	348	}
	349
	350	unselect(p)
	351	register struct proc *p;
	352	{
c4e1f1e5	353	register int s = splhigh();
88a7a62a SL	354
	355	switch (p->p_stat) {
	356
	357	case SSLEEP:
	358	setrun(p);
	359	break;
	360
	361	case SSTOP:
	362	unsleep(p);
	363	break;
	364	}
	365	splx(s);
	366	}
	367
d441e5bc	368	selscan(ibits, obits, nfd)
b8e71e77	369	fd_set ibits, obits;
88a7a62a	370	{
b8e71e77 MK	371	register int which, i, j;
b8e71e77 MK	372	register fd_mask bits;
88a7a62a SL	373	int flag;
	374	struct file *fp;
	375	int n = 0;
	376
	377	for (which = 0; which < 3; which++) {
88a7a62a SL	378	switch (which) {
	379
	380	case 0:
	381	flag = FREAD; break;
	382
	383	case 1:
	384	flag = FWRITE; break;
	385
	386	case 2:
	387	flag = 0; break;
	388	}
b8e71e77 MK	389	for (i = 0; i < nfd; i += NFDBITS) {
b8e71e77 MK	390	bits = ibits[which].fds_bits[i/NFDBITS];
d441e5bc MK	391	while ((j = ffs(bits)) && i + --j < nfd) {
	392	bits &= ~(1 << j);
	393	fp = u.u_ofile[i + j];
	394	if (fp == NULL) {
	395	u.u_error = EBADF;
	396	break;
	397	}
	398	if ((*fp->f_ops->fo_select)(fp, flag)) {
b8e71e77	399	FD_SET(i + j, &obits[which]);
d441e5bc MK	400	n++;
d441e5bc MK	401	}
88a7a62a SL	402	}
	403	}
	404	}
	405	return (n);
	406	}
	407
ffe28cfe	408	/ARGSUSED/
88a7a62a SL	409	seltrue(dev, flag)
	410	dev_t dev;
	411	int flag;
ffe28cfe BJ	412	{
ffe28cfe BJ	413
88a7a62a	414	return (1);
ffe28cfe	415	}
1edb1cf8	416
88a7a62a SL	417	selwakeup(p, coll)
	418	register struct proc *p;
	419	int coll;
1edb1cf8 BJ	420	{
1edb1cf8 BJ	421
88a7a62a SL	422	if (coll) {
	423	nselcoll++;
	424	wakeup((caddr_t)&selwait);
	425	}
	426	if (p) {
c4e1f1e5	427	int s = splhigh();
6bc3aba9 MK	428	if (p->p_wchan == (caddr_t)&selwait) {
	429	if (p->p_stat == SSLEEP)
	430	setrun(p);
	431	else
	432	unsleep(p);
	433	} else if (p->p_flag & SSEL)
88a7a62a SL	434	p->p_flag &= ~SSEL;
	435	splx(s);
	436	}
1edb1cf8	437	}