1 /*- 2 * Copyright (c) 2008 Bruce Simpson. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/param.h> 28 #include <sys/types.h> 29 #include <sys/ioctl.h> 30 31 #include <stdlib.h> 32 #include <stdio.h> 33 #include <string.h> 34 #include <errno.h> 35 #include <err.h> 36 #include <fcntl.h> 37 #include <unistd.h> 38 39 #include <libgen.h> 40 #include <sysexits.h> 41 42 #define DEVPATHNAME "/dev" 43 44 int 45 main(int argc, char *argv[]) 46 { 47 char *progname; 48 char *ttyname; 49 int fd; 50 int dofree; 51 52 dofree = 0; 53 54 progname = basename(argv[0]); 55 if (argc != 2) 56 errx(EX_USAGE, "usage: %s <ttyname>\n", progname); 57 if (geteuid() != 0) 58 errx(EX_NOPERM, "Sorry\n"); 59 60 if (argv[1][0] == '/') { 61 ttyname = argv[1]; 62 } else { 63 size_t len, maxpath, result; 64 65 len = strlen(argv[1]) + sizeof(DEVPATHNAME) + 1; 66 67 maxpath = pathconf(DEVPATHNAME, _PC_PATH_MAX); 68 if (len > maxpath) { 69 warnc(ENAMETOOLONG, ttyname); 70 exit(EX_DATAERR); 71 } 72 73 ttyname = malloc(len); 74 if (ttyname == NULL) { 75 warnc(ENOMEM, "malloc"); 76 exit(EX_OSERR); 77 } 78 dofree = 1; 79 80 result = snprintf(ttyname, len, "%s/%s", DEVPATHNAME, argv[1]); 81 if (result >= len) 82 warnc(ENOMEM, "snprintf"); 83 } 84 85 fd = open(ttyname, O_RDWR); 86 if (fd == -1) { 87 warnc(errno, "open %s", ttyname); 88 if (dofree) 89 free(ttyname); 90 exit(EX_OSERR); 91 } 92 93 if (0 != ioctl(fd, TIOCNXCL, 0)) 94 warnc(errno, "ioctl TIOCNXCL %s", ttyname); 95 96 if (dofree) 97 free(ttyname); 98 exit(0); 99 } 100