1 /* 2 * Copyright (c) 1988, 1993 3 * The Regents of the University of California. 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 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char rcsid[] = "$OpenBSD: ttyname.c,v 1.9 2003/06/02 20:18:35 millert Exp $"; 32 #endif /* LIBC_SCCS and not lint */ 33 34 #include <sys/types.h> 35 #include <sys/stat.h> 36 #include <fcntl.h> 37 #include <dirent.h> 38 #include <termios.h> 39 #include <db.h> 40 #include <string.h> 41 #include <unistd.h> 42 #include <paths.h> 43 #include <limits.h> 44 #include <errno.h> 45 #include "thread_private.h" 46 47 static char buf[TTY_NAME_MAX]; 48 static int oldttyname(int, struct stat *, char *, size_t); 49 static int __ttyname_r_basic(int, char *, size_t); 50 51 int 52 ttyname_r(int fd, char *buf, size_t buflen) 53 { 54 int ret; 55 56 if ((ret = _FD_LOCK(fd, FD_READ, NULL)) == 0) { 57 ret = __ttyname_r_basic(fd, buf, buflen); 58 _FD_UNLOCK(fd, FD_READ); 59 } 60 return ret; 61 } 62 63 char * 64 ttyname(int fd) 65 { 66 _THREAD_PRIVATE_KEY(ttyname); 67 char * bufp = (char*) _THREAD_PRIVATE(ttyname, buf, NULL); 68 int err; 69 70 if (bufp == NULL) 71 return NULL; 72 err = ttyname_r(fd, bufp, sizeof buf); 73 if (err) { 74 errno = err; 75 return NULL; 76 } 77 else 78 return bufp; 79 } 80 81 static int 82 __ttyname_r_basic(fd, buf, len) 83 int fd; 84 char *buf; 85 size_t len; 86 { 87 struct stat sb; 88 struct termios ttyb; 89 DB *db; 90 DBT data, key; 91 struct { 92 mode_t type; 93 dev_t dev; 94 } bkey; 95 96 /* Must be a terminal. */ 97 if (tcgetattr(fd, &ttyb) < 0) 98 return (errno); 99 /* Must be a character device. */ 100 if (fstat(fd, &sb)) 101 return (errno); 102 if (!S_ISCHR(sb.st_mode)) 103 return (ENOTTY); 104 if (len < sizeof(_PATH_DEV)) 105 return (ERANGE); 106 107 memcpy(buf, _PATH_DEV, sizeof(_PATH_DEV)); 108 109 if ((db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL))) { 110 memset(&bkey, 0, sizeof(bkey)); 111 bkey.type = S_IFCHR; 112 bkey.dev = sb.st_rdev; 113 key.data = &bkey; 114 key.size = sizeof(bkey); 115 if (!(db->get)(db, &key, &data, 0)) { 116 if (data.size > len - (sizeof(_PATH_DEV) - 1)) { 117 (void)(db->close)(db); 118 return (ERANGE); 119 } 120 memcpy(buf + sizeof(_PATH_DEV) - 1, data.data, 121 data.size); 122 (void)(db->close)(db); 123 return (0); 124 } 125 (void)(db->close)(db); 126 } 127 return (oldttyname(fd, &sb, buf, len)); 128 } 129 130 /* ARGSUSED */ 131 static int 132 oldttyname(fd, sb, buf, len) 133 int fd; 134 struct stat *sb; 135 char *buf; 136 size_t len; 137 { 138 register struct dirent *dirp; 139 register DIR *dp; 140 struct stat dsb; 141 142 if ((dp = opendir(_PATH_DEV)) == NULL) 143 return (errno); 144 145 while ((dirp = readdir(dp))) { 146 if (dirp->d_fileno != sb->st_ino) 147 continue; 148 if (dirp->d_namlen > len - sizeof(_PATH_DEV)) { 149 (void)closedir(dp); 150 return (ERANGE); 151 } 152 memcpy(buf + sizeof(_PATH_DEV) - 1, dirp->d_name, 153 dirp->d_namlen + 1); 154 if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev || 155 sb->st_ino != dsb.st_ino) 156 continue; 157 (void)closedir(dp); 158 return (0); 159 } 160 (void)closedir(dp); 161 return (ENOTTY); 162 } 163