1 /* $NetBSD: ttyname.c,v 1.9 1995/05/02 01:45:33 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1993 5 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)ttyname.c 8.2 (Berkeley) 1/27/94"; 39 #else 40 static char rcsid[] = "$NetBSD: ttyname.c,v 1.9 1995/05/02 01:45:33 mycroft Exp $"; 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include <sys/types.h> 45 #include <sys/stat.h> 46 #include <fcntl.h> 47 #include <dirent.h> 48 #include <termios.h> 49 #include <db.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include <paths.h> 53 54 static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV; 55 static char *oldttyname __P((int, struct stat *)); 56 57 char * 58 ttyname(fd) 59 int fd; 60 { 61 struct stat sb; 62 struct termios ttyb; 63 DB *db; 64 DBT data, key; 65 struct { 66 mode_t type; 67 dev_t dev; 68 } bkey; 69 70 /* Must be a terminal. */ 71 if (tcgetattr(fd, &ttyb) < 0) 72 return (NULL); 73 /* Must be a character device. */ 74 if (fstat(fd, &sb) || !S_ISCHR(sb.st_mode)) 75 return (NULL); 76 77 if (db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL)) { 78 memset(&bkey, 0, sizeof(bkey)); 79 bkey.type = S_IFCHR; 80 bkey.dev = sb.st_rdev; 81 key.data = &bkey; 82 key.size = sizeof(bkey); 83 if (!(db->get)(db, &key, &data, 0)) { 84 bcopy(data.data, 85 buf + sizeof(_PATH_DEV) - 1, data.size); 86 (void)(db->close)(db); 87 return (buf); 88 } 89 (void)(db->close)(db); 90 } 91 return (oldttyname(fd, &sb)); 92 } 93 94 static char * 95 oldttyname(fd, sb) 96 int fd; 97 struct stat *sb; 98 { 99 register struct dirent *dirp; 100 register DIR *dp; 101 struct stat dsb; 102 103 if ((dp = opendir(_PATH_DEV)) == NULL) 104 return (NULL); 105 106 while (dirp = readdir(dp)) { 107 if (dirp->d_fileno != sb->st_ino) 108 continue; 109 bcopy(dirp->d_name, buf + sizeof(_PATH_DEV) - 1, 110 dirp->d_namlen + 1); 111 if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev || 112 sb->st_ino != dsb.st_ino) 113 continue; 114 (void)closedir(dp); 115 return (buf); 116 } 117 (void)closedir(dp); 118 return (NULL); 119 } 120