xref: /freebsd/sbin/comcontrol/comcontrol.c (revision 4b4cf0d52c43e33c32983df60a8ea16b3d9e2f20)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1992 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote
16  *    products derived from this software without specific written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 #include <ctype.h>
33 #include <err.h>
34 #include <errno.h>
35 #include <fcntl.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <sys/types.h>
41 #include <sys/ioctl.h>
42 
43 static void usage(void) __dead2;
44 
45 static void
usage(void)46 usage(void)
47 {
48 	fprintf(stderr,
49 	"usage: comcontrol <filename> [drainwait <n>]\n");
50 	exit(1);
51 }
52 
53 int
main(int argc,char * argv[])54 main(int argc, char *argv[])
55 {
56 	int	fd;
57 	int     res = 0;
58 	int     print_drainwait = 1;
59 	int     drainwait = -1;
60 
61 	if (argc < 2)
62 		usage();
63 
64 	if (strcmp(argv[1], "-") == 0)
65 		fd = STDIN_FILENO;
66 	else {
67 		fd = open(argv[1], O_RDONLY|O_NONBLOCK, 0);
68 		if (fd < 0) {
69 			warn("couldn't open file %s", argv[1]);
70 			return 1;
71 		}
72 	}
73 	if (argc == 2) {
74 		if (ioctl(fd, TIOCGDRAINWAIT, &drainwait) < 0) {
75 			print_drainwait = 0;
76 			if (errno != ENOTTY) {
77 				res = 1;
78 				warn("TIOCGDRAINWAIT");
79 			}
80 		}
81 		if (print_drainwait)
82 			printf("drainwait %d ", drainwait);
83 		printf("\n");
84 	} else {
85 		while (argv[2] != NULL) {
86 			if (!strcmp(argv[2],"drainwait")) {
87 				if (drainwait >= 0)
88 					usage();
89 				if (argv[3] == NULL || !isdigit(argv[3][0]))
90 					usage();
91 				drainwait = atoi(argv[3]);
92 				argv += 2;
93 			} else
94 				usage();
95 		}
96 		if (drainwait >= 0) {
97 			if (ioctl(fd, TIOCSDRAINWAIT, &drainwait) < 0) {
98 				res = 1;
99 				warn("TIOCSDRAINWAIT");
100 			}
101 		}
102 	}
103 
104 	close(fd);
105 	return res;
106 }
107