Add an -S option that allows the user to disable vty switching. It is

implemented using a new VT_LOCKSWITCH ioctl.  Although it is possible
to implement something like this by VT_SETMODEing to VT_PROCESS and
never releasing the vty, that method has a number of downsides, the
biggest of which is that some program has to stay resident for the
lock to be in effect.

Reviewed by:	roam, sheldonh

2 files changed, 29 insertions, 3 deletions

diff --git a/usr.sbin/vidcontrol/vidcontrol.1 b/usr.sbin/vidcontrol/vidcontrol.1
index 332643c..0fca733 100644
--- a/usr.sbin/vidcontrol/vidcontrol.1
+++ b/usr.sbin/vidcontrol/vidcontrol.1
@@ -13,7 +13,7 @@
 .\"     @(#)vidcontrol.1
 .\" $FreeBSD$
 .\"
-.Dd May 27, 2001
+.Dd May 27, 2002
 .Dt VIDCONTROL 1
 .Os
 .Sh NAME
@@ -36,6 +36,7 @@
 .Op Fl M Ar char
 .Op Fl m Cm on | off
 .Op Fl r Ar foreground Ar background
+.Op Fl S Cm on | off
 .Op Fl s Ar number
 .Op Fl t Ar N | Cm off
 .Op Ar mode
@@ -213,6 +214,11 @@ Change reverse mode colors to
 .Ar foreground
 and
 .Ar background .
+.It Fl S Cm on | off
+Turn vty switching on or off.
+When vty switching is off,
+attempts to switch to a different virtual terminal will fail.
+(The default is to permit vty switching.)
 .It Fl s Ar number
 Set the current vty to
 .Ar number .
diff --git a/usr.sbin/vidcontrol/vidcontrol.c b/usr.sbin/vidcontrol/vidcontrol.c
index 3bc73d1..5f0d018 100644
--- a/usr.sbin/vidcontrol/vidcontrol.c
+++ b/usr.sbin/vidcontrol/vidcontrol.c
@@ -76,7 +76,7 @@ usage()
 "usage: vidcontrol [-CdLPpx] [-b color] [-c appearance] [-f [size] file]",
 "                  [-g geometry] [-h size] [-i adapter | mode] [-l screen_map]",
 "                  [-m on | off] [-M char] [-r foreground background] [-s num]",
-"                  [-t N | off] [mode] [foreground [background]] [show]");
+"                  [-S on | off] [-t N | off] [mode] [foreground [background]] [show]");
 	exit(1);
 }
 
@@ -518,6 +518,23 @@ set_mouse(char *arg)
 	ioctl(0, CONS_MOUSECTL, &mouse);
 }
 
+void
+set_lockswitch(char *arg)
+{
+	int data;
+
+	if (!strcmp(arg, "off"))
+		data = 0x01;
+	else if (!strcmp(arg, "on"))
+		data = 0x02;
+	else {
+		warnx("argument to -S must either on or off");
+		return;
+	}
+	if (ioctl(0, VT_LOCKSWITCH, &data) == -1)
+		warn("ioctl(VT_LOCKSWITCH)");
+}
+
 static char
 *adapter_name(int type)
 {
@@ -749,7 +766,7 @@ main(int argc, char **argv)
 		/* Not reached */
 	if (ioctl(0, CONS_GETINFO, &info) < 0)
 		err(1, "must be on a virtual console");
-	while((opt = getopt(argc, argv, "b:Cc:df:g:h:i:l:LM:m:pPr:s:t:x")) != -1)
+	while((opt = getopt(argc, argv, "b:Cc:df:g:h:i:l:LM:m:pPr:S:s:t:x")) != -1)
 		switch(opt) {
 		case 'b':
 			set_border_color(optarg);
@@ -806,6 +823,9 @@ main(int argc, char **argv)
 		case 'r':
 			set_reverse_colors(argc, argv, &optind);
 			break;
+		case 'S':
+			set_lockswitch(optarg);
+			break;
 		case 's':
 			set_console(optarg);
 			break;