From b5e878b40249e4541bb93a4b059056ce01d40e8d Mon Sep 17 00:00:00 2001
From: julian <julian@FreeBSD.org>
Date: Tue, 17 Aug 1999 23:08:51 +0000
Subject: [PATCH] Devfs isn't quite dead yet... Add back devfs support to
 ptys.. When you use pty(N) it creates pty(N+1) ready for your use in the
 DEVFS, so DEVFS is not cluttered up with hundreds of ptys you are never going
 to use.

---
 sys/kern/tty_pty.c | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index 160693f7bf9a..f2b2da747d6e 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 1.62 1999/08/08 19:28:50 phk Exp $
+ * $Id: tty_pty.c,v 1.63 1999/08/08 19:47:32 phk Exp $
  */
 
 /*
@@ -40,6 +40,7 @@
  */
 #include "pty.h"		/* XXX */
 #include "opt_compat.h"
+#include "opt_devfs.h"
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -56,6 +57,10 @@
 #include <sys/signalvar.h>
 #include <sys/malloc.h>
 
+#ifdef DEVFS
+#include <sys/devfsext.h>
+#endif /*DEVFS*/
+
 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
 
 static void ptsstart __P((struct tty *tp));
@@ -129,6 +134,10 @@ struct	pt_ioctl {
 	u_char	pt_send;
 	u_char	pt_ucntl;
 	struct tty pt_tty;
+#ifdef DEVFS
+	void    *devfs_token_pts;
+	void    *devfs_token_ptc;
+#endif /* DEVFS */
 };
 
 #define	PF_PKT		0x08		/* packet mode */
@@ -168,6 +177,14 @@ ptyinit(n)
 	devs->si_drv1 = devc->si_drv1 = pt;
 	devs->si_tty_tty = devc->si_tty_tty = &pt->pt_tty;
 	ttyregister(&pt->pt_tty);
+#ifdef DEVFS
+	pt->devfs_token_pts = devfs_add_devswf(&pts_cdevsw,n,
+				DV_CHR,0,0,0666,
+				devs->si_name);
+	pt->devfs_token_ptc = devfs_add_devswf(&ptc_cdevsw,n,
+				DV_CHR,0,0,0666,
+				devc->si_name);
+#endif /* DEVFS */
 }
 
 /*ARGSUSED*/
@@ -179,7 +196,22 @@ ptsopen(dev, flag, devtype, p)
 {
 	register struct tty *tp;
 	int error;
+#ifdef	DEVFS
+	int minr;
+	dev_t nextdev;
 
+	/*
+	 * If we openned this device, ensure we have the
+	 * next ready in the DEVFS (up to 256 of them).
+	 */
+	minr = lminor(dev);
+	if (minr < 255) {
+		nextdev = makedev(major(dev), minr + 1);
+		if (!nextdev->si_drv1) {
+			ptyinit(minr + 1);
+		}
+	}
+#endif /* DEVFS */
 	if (!dev->si_drv1)
 		ptyinit(minor(dev));
 	if (!dev->si_drv1)
@@ -827,6 +859,9 @@ ptc_drvinit(unused)
 		cdevsw_add(&ptc_cdevsw);
 		ptc_devsw_installed = 1;
     	}
+#ifdef	DEVFS
+	ptyinit(0); /* Add the first pty into the system.. prime the pump */
+#endif	/* DEVFS */
 }
 
 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)