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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)ttyname.c 8.2 (Berkeley) 1/27/94"; 36 #endif /* LIBC_SCCS and not lint */ 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "namespace.h" 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 #include <fcntl.h> 44 #include <dirent.h> 45 #include <stdlib.h> 46 #include <termios.h> 47 #include <unistd.h> 48 #include <string.h> 49 #include <paths.h> 50 #include <pthread.h> 51 #include "un-namespace.h" 52 53 #include "libc_private.h" 54 55 static char buf[sizeof(_PATH_DEV) + MAXNAMLEN]; 56 static char *oldttyname(int, struct stat *); 57 static char *ttyname_threaded(int fd); 58 static char *ttyname_unthreaded(int fd); 59 60 static pthread_mutex_t ttyname_lock = PTHREAD_MUTEX_INITIALIZER; 61 static pthread_key_t ttyname_key; 62 static int ttyname_init = 0; 63 64 char * 65 ttyname(int fd) 66 { 67 char *ret; 68 69 if (__isthreaded == 0) 70 ret = ttyname_unthreaded(fd); 71 else 72 ret = ttyname_threaded(fd); 73 return (ret); 74 } 75 76 char * 77 ttyname_r(int fd, char *buf, size_t len) 78 { 79 struct stat dsb; 80 struct stat sb; 81 char *rval; 82 int minlen; 83 84 rval = NULL; 85 86 /* Must be a terminal. */ 87 if (!isatty(fd)) 88 return (rval); 89 /* Must be a character device. */ 90 if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode)) 91 return (rval); 92 /* Must have enough room */ 93 if (len <= sizeof(_PATH_DEV)) 94 return (rval); 95 96 strcpy(buf, _PATH_DEV); 97 devname_r(sb.st_rdev, S_IFCHR, 98 buf + strlen(buf), sizeof(buf) - strlen(buf)); 99 return (buf); 100 } 101 102 static char * 103 ttyname_threaded(int fd) 104 { 105 char *buf; 106 107 if (ttyname_init == 0) { 108 _pthread_mutex_lock(&ttyname_lock); 109 if (ttyname_init == 0) { 110 if (_pthread_key_create(&ttyname_key, free)) { 111 _pthread_mutex_unlock(&ttyname_lock); 112 return (NULL); 113 } 114 ttyname_init = 1; 115 } 116 _pthread_mutex_unlock(&ttyname_lock); 117 } 118 119 /* Must have thread specific data field to put data */ 120 if ((buf = _pthread_getspecific(ttyname_key)) == NULL) { 121 if ((buf = malloc(sizeof(_PATH_DEV) + MAXNAMLEN)) != NULL) { 122 if (_pthread_setspecific(ttyname_key, buf) != 0) { 123 free(buf); 124 return (NULL); 125 } 126 } else { 127 return (NULL); 128 } 129 } 130 return (ttyname_r(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN)); 131 } 132 133 static char * 134 ttyname_unthreaded(int fd) 135 { 136 struct stat sb; 137 struct termios ttyb; 138 139 /* Must be a terminal. */ 140 if (tcgetattr(fd, &ttyb) < 0) 141 return (NULL); 142 /* Must be a character device. */ 143 if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode)) 144 return (NULL); 145 146 strcpy(buf, _PATH_DEV); 147 devname_r(sb.st_rdev, S_IFCHR, 148 buf + strlen(buf), sizeof(buf) - strlen(buf)); 149 return (buf); 150 } 151