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)

1 files changed, 42 insertions, 46 deletions

diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index cc46c2a..34e1029 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