Allow "-" for working with STDIN

Allow printing of each option separately when keyword specified without a
number

2 files changed, 50 insertions, 16 deletions

diff --git a/sbin/comcontrol/comcontrol.8 b/sbin/comcontrol/comcontrol.8
index 4b12b6e0be0c..84ef5b5817c3 100644
--- a/sbin/comcontrol/comcontrol.8
+++ b/sbin/comcontrol/comcontrol.8
@@ -4,22 +4,26 @@
 .Os FreeBSD
 .Sh NAME
 .Nm comcontrol
-.Nd control an sio device.
+.Nd control an special tty device.
 .Sh SYNOPSIS
 .Nm comcontrol
-.Ar sio_special_device
-.Op options
+.Ar special_device | -
+.Op dtrwait Op number
+.Op drainwait Op number
 .Sh DESCRIPTION
 .Nm Comcontrol
 is used to examine and modify some of the special characteristics
-of the specified sio device.
-If no arguments other than the device are specified,
+of the specified tty device.
+If no arguments other than the device (or "-" for stdin)
+are specified,
 it prints the settings of all controllable characteristics.
 This usage requires only read access on the device.
 Only the superuser can change the settings.
 .Pp
 The following options are available:
 .Bl -tag -width indent
+.It Cm dtrwait
+Print current DTR wait time.
 .It Cm dtrwait Ar number
 Set the time to wait after dropping DTR
 to the given number.
@@ -27,11 +31,14 @@ The units are hundredths of a second.
 The default is 300 hundredths, i.e., 3 seconds.
 This option needed mainly to set proper recover time after
 modem reset.
+.It Cm drainwait
+Print current output drain timeout.
 .It Cm drainwait Ar number
 Set the time to wait for output drain
 to the given number.
 The units are seconds.
-The default is 0, i.e. wait forever.
+The default is 5 minutes, 0 means
+waiting forever.
 This option needed mainly to specify upper limit of minutes
 to prevent modem hanging.
 .El
diff --git a/sbin/comcontrol/comcontrol.c b/sbin/comcontrol/comcontrol.c
index 671551e07d60..7de222513b28 100644
--- a/sbin/comcontrol/comcontrol.c
+++ b/sbin/comcontrol/comcontrol.c
@@ -44,7 +44,7 @@ static void
 usage()
 {
 	fprintf(stderr,
-	"usage: comcontrol <filename> [dtrwait <n>] [drainwait <n>]\n");
+	"usage: comcontrol <filename|-> [dtrwait [<n>]] [drainwait [<n>]]\n");
 	exit(1);
 }
 
@@ -54,14 +54,20 @@ main(int argc, char *argv[])
 	int	fd;
 	int     res = 0;
 	int     dtrwait = -1, drainwait = -1;
+	int     temp;
+	int     output = 0;
 
 	if (argc < 2)
 		usage();
 
-	fd = open(argv[1], O_RDONLY|O_NONBLOCK, 0);
-	if (fd < 0) {
-		warn("couldn't open file %s", argv[1]);
-		return 1;
+	if (strcmp(argv[1], "-") == 0)
+		fd = STDIN_FILENO;
+	else {
+		fd = open(argv[1], O_RDONLY|O_NONBLOCK, 0);
+		if (fd < 0) {
+			warn("couldn't open file %s", argv[1]);
+			return 1;
+		}
 	}
 
 	if (argc == 2) {
@@ -73,21 +79,40 @@ main(int argc, char *argv[])
 			res = 1;
 			warn("TIOCGDRAINWAIT");
 		}
-		printf("dtrwait %d drainwait %d\n", dtrwait, drainwait);
+		printf("dtrwait %d drainwait %d ", dtrwait, drainwait);
+		output = 1;
 	} else {
 		while (argv[2] != NULL) {
 			if (!strcmp(argv[2],"dtrwait")) {
+				if (argv[3] == NULL || !isdigit(argv[3][0])) {
+					if (ioctl(fd, TIOCMGDTRWAIT, &temp) < 0) {
+						res = 1;
+						temp = -1;
+						warn("TIOCMGDTRWAIT");
+					}
+					printf("dtrwait %d ", temp);
+					output = 1;
+					argv++;
+					continue;
+				}
 				if (dtrwait >= 0)
 					usage();
-				if (argv[3] == NULL || !isdigit(argv[3][0]))
-					usage();
 				dtrwait = atoi(argv[3]);
 				argv += 2;
 			} else if (!strcmp(argv[2],"drainwait")) {
+				if (argv[3] == NULL || !isdigit(argv[3][0])) {
+					if (ioctl(fd, TIOCGDRAINWAIT, &temp) < 0) {
+						res = 1;
+						temp = -1;
+						warn("TIOCGDRAINWAIT");
+					}
+					printf("drainwait %d ", temp);
+					argv++;
+					output = 1;
+					continue;
+				}
 				if (drainwait >= 0)
 					usage();
-				if (argv[3] == NULL || !isdigit(argv[3][0]))
-					usage();
 				drainwait = atoi(argv[3]);
 				argv += 2;
 			} else
@@ -108,5 +133,7 @@ main(int argc, char *argv[])
 	}
 
 	close(fd);
+	if (output)
+		printf("\n");
 	return res;
 }