1 /* $NetBSD: ttyname.c,v 1.26 2012/06/12 18:17:04 joerg 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 1.26 2012/06/12 18:17:04 joerg Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/ioctl.h> 43 #include <sys/stat.h> 44 45 #include <assert.h> 46 #include <errno.h> 47 #include <limits.h> 48 #include <paths.h> 49 #include <string.h> 50 #include <stdlib.h> 51 #include <termios.h> 52 #include <unistd.h> 53 54 #ifdef __weak_alias 55 __weak_alias(ttyname,_ttyname) 56 __weak_alias(ttyname_r,_ttyname_r) 57 #endif 58 59 #if defined(__minix) 60 /* LSC: We do not have devname functionality on Minix, so re-import for now 61 * old, manual way of doing it.*/ 62 #include <dirent.h> 63 static int 64 oldttyname(const struct stat *sb, char *buf, size_t len) 65 { 66 struct dirent *dirp; 67 DIR *dp; 68 struct stat dsb; 69 size_t dlen; 70 71 _DIAGASSERT(sb != NULL); 72 73 if ((dp = opendir(_PATH_DEV)) == NULL) 74 return -1; 75 76 while ((dirp = readdir(dp)) != NULL) { 77 #define DEVSZ (sizeof(_PATH_DEV) - 1) 78 if (dirp->d_fileno != sb->st_ino) 79 continue; 80 dlen = strlen(dirp->d_name); 81 if (len - DEVSZ <= dlen) { 82 /* 83 * XXX: we return an error if *any* entry does not 84 * fit 85 */ 86 errno = ERANGE; 87 (void)closedir(dp); 88 return -1; 89 } 90 (void)memcpy(buf + DEVSZ, dirp->d_name, dlen); 91 if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev || 92 sb->st_ino != dsb.st_ino) 93 continue; 94 (void)closedir(dp); 95 return 0; 96 #undef DEVSZ 97 } 98 (void)closedir(dp); 99 /* 100 * XXX: Documented by TOG to return EBADF or ENOTTY only; neither are 101 * applicable here. 102 */ 103 errno = ENOENT; 104 return -1; 105 } 106 107 #endif /* defined(__minix) */ 108 109 int 110 ttyname_r(int fd, char *buf, size_t len) 111 { 112 struct stat sb; 113 struct termios ttyb; 114 #if !defined(__minix) 115 struct ptmget ptm; 116 #endif /* !defined(__minix) */ 117 118 _DIAGASSERT(fd != -1); 119 120 #if !defined(__minix) 121 /* If it is a pty, deal with it quickly */ 122 if (ioctl(fd, TIOCPTSNAME, &ptm) != -1) { 123 if (strlcpy(buf, ptm.sn, len) >= len) { 124 return ERANGE; 125 } 126 return 0; 127 } 128 #endif /* !defined(__minix) */ 129 130 /* Must be a terminal. */ 131 if (tcgetattr(fd, &ttyb) == -1) 132 return errno; 133 134 if (fstat(fd, &sb)) 135 return errno; 136 137 if (strlcpy(buf, _PATH_DEV, len) >= len) 138 return ERANGE; 139 140 #if defined(__minix) 141 if (oldttyname(&sb, buf, len) == -1) 142 return errno; 143 return 0; 144 #else 145 buf += strlen(_PATH_DEV); 146 len -= strlen(_PATH_DEV); 147 return devname_r(sb.st_rdev, sb.st_mode & S_IFMT, buf, len); 148 #endif /* defined(__minix) */ 149 } 150 151 char * 152 ttyname(int fd) 153 { 154 static char buf[PATH_MAX]; 155 int rv; 156 157 rv = ttyname_r(fd, buf, sizeof(buf)); 158 if (rv != 0) { 159 errno = rv; 160 return NULL; 161 } 162 return buf; 163 } 164