1 /* $NetBSD: ttyname.c,v 1.24 2008/06/25 11:47:29 ad 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)ttyname.c 8.2 (Berkeley) 1/27/94"; 36 #else 37 __RCSID("$NetBSD: ttyname.c,v 1.24 2008/06/25 11:47:29 ad Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/types.h> 43 #include <sys/param.h> 44 #include <sys/stat.h> 45 46 #include <assert.h> 47 #include <db.h> 48 #include <dirent.h> 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <paths.h> 52 #include <string.h> 53 #include <termios.h> 54 #include <unistd.h> 55 #include <sys/ioctl.h> 56 57 #ifdef __weak_alias 58 __weak_alias(ttyname,_ttyname) 59 __weak_alias(ttyname_r,_ttyname_r) 60 #endif 61 62 static int oldttyname(const struct stat *, char *, size_t); 63 64 int 65 ttyname_r(int fd, char *buf, size_t len) 66 { 67 struct stat sb; 68 struct termios ttyb; 69 DB *db; 70 DBT data, key; 71 struct { 72 mode_t type; 73 dev_t dev; 74 } bkey; 75 #ifndef __minix 76 struct ptmget ptm; 77 #endif 78 #define DEVSZ (sizeof(_PATH_DEV) - 1) 79 80 _DIAGASSERT(fd != -1); 81 82 if (len <= DEVSZ) { 83 return ERANGE; 84 } 85 86 #ifndef __minix 87 /* If it is a pty, deal with it quickly */ 88 if (ioctl(fd, TIOCPTSNAME, &ptm) != -1) { 89 if (strlcpy(buf, ptm.sn, len) >= len) { 90 return ERANGE; 91 } 92 return 0; 93 } 94 #endif 95 /* Must be a terminal. */ 96 if (tcgetattr(fd, &ttyb) == -1) 97 return errno; 98 99 /* Must be a character device. */ 100 if (fstat(fd, &sb)) 101 return errno; 102 if (!S_ISCHR(sb.st_mode)) 103 return ENOTTY; 104 105 (void)memcpy(buf, _PATH_DEV, DEVSZ); 106 if ((db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL)) != NULL) { 107 (void)memset(&bkey, 0, sizeof(bkey)); 108 bkey.type = S_IFCHR; 109 bkey.dev = sb.st_rdev; 110 key.data = &bkey; 111 key.size = sizeof(bkey); 112 if (!(db->get)(db, &key, &data, 0)) { 113 if (len - DEVSZ <= data.size) { 114 return ERANGE; 115 } 116 (void)memcpy(buf + DEVSZ, data.data, data.size); 117 (void)(db->close)(db); 118 return 0; 119 } 120 (void)(db->close)(db); 121 } 122 if (oldttyname(&sb, buf, len) == -1) 123 return errno; 124 return 0; 125 } 126 127 static int 128 oldttyname(const struct stat *sb, char *buf, size_t len) 129 { 130 struct dirent *dirp; 131 DIR *dp; 132 struct stat dsb; 133 size_t dlen; 134 135 _DIAGASSERT(sb != NULL); 136 137 if ((dp = opendir(_PATH_DEV)) == NULL) 138 return -1; 139 140 while ((dirp = readdir(dp)) != NULL) { 141 if (dirp->d_fileno != sb->st_ino) 142 continue; 143 #ifdef __minix 144 dlen = strlen(dirp->d_name); 145 #else 146 dlen = dirp->d_namlen + 1; 147 #endif 148 if (len - DEVSZ <= dlen) { 149 /* 150 * XXX: we return an error if *any* entry does not 151 * fit 152 */ 153 errno = ERANGE; 154 (void)closedir(dp); 155 return -1; 156 } 157 (void)memcpy(buf + DEVSZ, dirp->d_name, dlen); 158 if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev || 159 sb->st_ino != dsb.st_ino) 160 continue; 161 (void)closedir(dp); 162 return 0; 163 } 164 (void)closedir(dp); 165 /* 166 * XXX: Documented by TOG to return EBADF or ENOTTY only; neither are 167 * applicable here. 168 */ 169 errno = ENOENT; 170 return -1; 171 } 172 173 char * 174 ttyname(int fd) 175 { 176 static char buf[MAXPATHLEN]; 177 int rv; 178 179 rv = ttyname_r(fd, buf, sizeof(buf)); 180 if (rv != 0) { 181 errno = rv; 182 return NULL; 183 } 184 return buf; 185 } 186