Extend to use poll backend. If memory serves correctly, most of this was

adapted from NetBSD..  However, there are some differences in the tty
system that are big enough to cause their code to not fit comfortably.

Obtained from:  NetBSD (I think)

3 files changed, 73 insertions, 75 deletions

diff --git a/sys/kern/tty.c b/sys/kern/tty.c
index 0c023ea24a57..0be04a0c3553 100644
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty.c	8.8 (Berkeley) 1/21/94
- * $Id: tty.c,v 1.94 1997/03/24 12:02:59 bde Exp $
+ * $Id: tty.c,v 1.95 1997/09/02 20:05:54 bde Exp $
  */
 
 /*-
@@ -83,6 +83,7 @@
 #include <sys/fcntl.h>
 #include <sys/conf.h>
 #include <sys/dkstat.h>
+#include <sys/poll.h>
 #include <sys/kernel.h>
 #include <sys/vnode.h>
 #include <sys/signalvar.h>
@@ -1031,35 +1032,34 @@ ttioctl(tp, cmd, data, flag)
 }
 
 int
-ttyselect(tp, rw, p)
+ttypoll(tp, events, p)
 	struct tty *tp;
-	int rw;
+	int events;
 	struct proc *p;
 {
 	int s;
+	int revents = 0;
 
-	if (tp == NULL)
-		return (ENXIO);
+	if (tp == NULL)	/* XXX used to return ENXIO, but that means true! */
+		return ((events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM))
+			| POLLHUP);
 
 	s = spltty();
-	switch (rw) {
-	case FREAD:
+	if (events & (POLLIN | POLLRDNORM))
 		if (ttnread(tp) > 0 || ISSET(tp->t_state, TS_ZOMBIE))
-			goto win;
-		selrecord(p, &tp->t_rsel);
-		break;
-	case FWRITE:
+			revents |= events & (POLLIN | POLLRDNORM);
+		else
+			selrecord(p, &tp->t_rsel);
+
+	if (events & (POLLOUT | POLLWRNORM))
 		if ((tp->t_outq.c_cc <= tp->t_lowat &&
 		     ISSET(tp->t_state, TS_CONNECTED))
-		    || ISSET(tp->t_state, TS_ZOMBIE)) {
-win:			splx(s);
-			return (1);
-		}
-		selrecord(p, &tp->t_wsel);
-		break;
-	}
+		    || ISSET(tp->t_state, TS_ZOMBIE))
+			revents |= events & (POLLOUT | POLLWRNORM);
+		else
+			selrecord(p, &tp->t_wsel);
 	splx(s);
-	return (0);
+	return (revents);
 }
 
 /*
@@ -1067,12 +1067,12 @@ win:			splx(s);
  * cdevsw.  It relies on a proper xxxdevtotty routine.
  */
 int
-ttselect(dev, rw, p)
+ttpoll(dev, events, p)
 	dev_t dev;
-	int rw;
+	int events;
 	struct proc *p;
 {
-	return ttyselect((*cdevsw[major(dev)]->d_devtotty)(dev), rw, p);
+	return ttypoll((*cdevsw[major(dev)]->d_devtotty)(dev), events, p);
 }
 
 /*
diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index cc46c2ae03a8..34e10294bfde 100644
--- a/sys/kern/tty_pty.c
+++ b/sys/kern/tty_pty.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty_pty.c	8.4 (Berkeley) 2/20/95
- * $Id: tty_pty.c,v 1.44 1997/07/30 10:05:18 jmg Exp $
+ * $Id: tty_pty.c,v 1.45 1997/09/02 20:05:55 bde Exp $
  */
 
 /*
@@ -49,6 +49,7 @@
 #include <sys/tty.h>
 #include <sys/conf.h>
 #include <sys/fcntl.h>
+#include <sys/poll.h>
 #include <sys/kernel.h>
 #include <sys/vnode.h>
 #include <sys/signalvar.h>
@@ -74,19 +75,19 @@ static	d_open_t	ptcopen;
 static	d_close_t	ptcclose;
 static	d_read_t	ptcread;
 static	d_write_t	ptcwrite;
-static	d_select_t	ptcselect;
+static	d_poll_t	ptcpoll;
 
 #define CDEV_MAJOR_S 5
 #define CDEV_MAJOR_C 6
 static struct cdevsw pts_cdevsw = 
 	{ ptsopen,	ptsclose,	ptsread,	ptswrite,	/*5*/
 	  ptyioctl,	ptsstop,	nullreset,	ptydevtotty,/* ttyp */
-	  ttselect,	nommap,		NULL,	"pts",	NULL,	-1 };
+	  ttpoll,	nommap,		NULL,	"pts",	NULL,	-1 };
 
 static struct cdevsw ptc_cdevsw = 
 	{ ptcopen,	ptcclose,	ptcread,	ptcwrite,	/*6*/
 	  ptyioctl,	nullstop,	nullreset,	ptydevtotty,/* ptyp */
-	  ptcselect,	nommap,		NULL,	"ptc",	NULL,	-1 };
+	  ptcpoll,	nommap,		NULL,	"ptc",	NULL,	-1 };
 
 
 #if NPTY == 1
@@ -459,58 +460,53 @@ ptsstop(tp, flush)
 }
 
 static	int
-ptcselect(dev, rw, p)
+ptcpoll(dev, events, p)
 	dev_t dev;
-	int rw;
+	int events;
 	struct proc *p;
 {
 	register struct tty *tp = &pt_tty[minor(dev)];
 	struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	int revents = 0;
 	int s;
 
 	if ((tp->t_state & TS_CONNECTED) == 0)
-		return (1);
-	switch (rw) {
-
-	case FREAD:
-		/*
-		 * Need to block timeouts (ttrstart).
-		 */
-		s = spltty();
-		if ((tp->t_state&TS_ISOPEN) &&
-		     tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0) {
-			splx(s);
-			return (1);
-		}
-		splx(s);
-		/* FALLTHROUGH */
-
-	case 0:					/* exceptional */
-		if ((tp->t_state&TS_ISOPEN) &&
-		    ((pti->pt_flags&PF_PKT && pti->pt_send) ||
-		     (pti->pt_flags&PF_UCNTL && pti->pt_ucntl)))
-			return (1);
-		selrecord(p, &pti->pt_selr);
-		break;
-
-
-	case FWRITE:
-		if (tp->t_state&TS_ISOPEN) {
-			if (pti->pt_flags & PF_REMOTE) {
-			    if (tp->t_canq.c_cc == 0)
-				return (1);
-			} else {
-			    if (tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2)
-				    return (1);
-			    if (tp->t_canq.c_cc == 0 && (tp->t_iflag&ICANON))
-				    return (1);
-			}
-		}
-		selrecord(p, &pti->pt_selw);
-		break;
+		return (seltrue(dev, events, p) | POLLHUP);
 
+	/*
+	 * Need to block timeouts (ttrstart).
+	 */
+	s = spltty();
+
+	if (events & (POLLIN | POLLRDNORM))
+		if ((tp->t_state & TS_ISOPEN) &&
+		    ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
+		     ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
+		     ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)))
+			revents |= events & (POLLIN | POLLRDNORM);
+
+	if (events & (POLLOUT | POLLWRNORM))
+		if (tp->t_state & TS_ISOPEN &&
+		    ((pti->pt_flags & PF_REMOTE) ?
+		     (tp->t_canq.c_cc == 0) : 
+		     ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
+		      (tp->t_canq.c_cc == 0 && (tp->t_iflag & ICANON)))))
+			revents |= events & (POLLOUT | POLLWRNORM);
+
+	if (events & POLLHUP)
+		if ((tp->t_state & TS_CARR_ON) == 0)
+			revents |= POLLHUP;
+
+	if (revents == 0) {
+		if (events & (POLLIN | POLLRDNORM))
+			selrecord(p, &pti->pt_selr);
+
+		if (events & (POLLOUT | POLLWRNORM)) 
+			selrecord(p, &pti->pt_selw);
 	}
-	return (0);
+	splx(s);
+
+	return (revents);
 }
 
 static	int
diff --git a/sys/kern/tty_tty.c b/sys/kern/tty_tty.c
index bc0de91dd528..fb648b1f4557 100644
--- a/sys/kern/tty_tty.c
+++ b/sys/kern/tty_tty.c
@@ -31,13 +31,14 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty_tty.c	8.2 (Berkeley) 9/23/93
- * $Id: tty_tty.c,v 1.16 1997/03/24 11:24:38 bde Exp $
+ * $Id: tty_tty.c,v 1.17 1997/09/02 20:05:56 bde Exp $
  */
 
 /*
  * Indirect driver for controlling tty.
  */
 #include <sys/param.h>
+#include <sys/systm.h>
 #include <sys/conf.h>
 #include <sys/proc.h>
 #include <sys/tty.h>
@@ -52,14 +53,14 @@ static	d_open_t	cttyopen;
 static	d_read_t	cttyread;
 static	d_write_t	cttywrite;
 static	d_ioctl_t	cttyioctl;
-static	d_select_t	cttyselect;
+static	d_poll_t	cttypoll;
 
 #define CDEV_MAJOR 1
 /* Don't make static, fdesc_vnops uses this. */
 struct cdevsw ctty_cdevsw = 
 	{ cttyopen,	nullclose,	cttyread,	cttywrite,	/*1*/
 	  cttyioctl,	nullstop,	nullreset,	nodevtotty,/* tty */
-	  cttyselect,	nommap,		NULL,	"ctty",	NULL,	-1 };
+	  cttypoll,	nommap,		NULL,	"ctty",	NULL,	-1 };
 
 
 #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
@@ -160,16 +161,17 @@ cttyioctl(dev, cmd, addr, flag, p)
 
 /*ARGSUSED*/
 static	int
-cttyselect(dev, flag, p)
+cttypoll(dev, events, p)
 	dev_t dev;
-	int flag;
+	int events;
 	struct proc *p;
 {
 	struct vnode *ttyvp = cttyvp(p);
 
 	if (ttyvp == NULL)
-		return (1);	/* try operation to get EOF/failure */
-	return (VOP_SELECT(ttyvp, flag, FREAD|FWRITE, NOCRED, p));
+		/* try operation to get EOF/failure */
+		return (seltrue(dev, events, p));
+	return (VOP_POLL(ttyvp, events, p->p_ucred, p));
 }
 
 static ctty_devsw_installed = 0;