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 * 4. 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 * @(#)ttyname.c 8.2 (Berkeley) 1/27/94 30 * $FreeBSD: src/lib/libc/gen/ttyname.c,v 1.24 2007/01/09 00:27:55 imp Exp $ 31 * $DragonFly: src/lib/libc/gen/ttyname.c,v 1.14 2005/11/19 22:32:53 swildner Exp $ 32 */ 33 34 #include "namespace.h" 35 #include <sys/types.h> 36 #include <fcntl.h> 37 #include <dirent.h> 38 #include <stdlib.h> 39 #include <termios.h> 40 #include <unistd.h> 41 #include <string.h> 42 #include <paths.h> 43 #include <errno.h> 44 #include <machine/stdint.h> 45 #include <sys/stat.h> 46 #include <sys/ioctl.h> 47 #include "reentrant.h" 48 #include "un-namespace.h" 49 50 #include "libc_private.h" 51 52 #define TTYNAME_DEVFS_COMPAT 1 53 54 static char ttyname_buf[sizeof(_PATH_DEV) + NAME_MAX]; 55 56 static once_t ttyname_init_once = ONCE_INITIALIZER; 57 static thread_key_t ttyname_key; 58 static int ttyname_keycreated = 0; 59 60 int 61 ttyname_r(int fd, char *buf, size_t len) 62 { 63 struct stat sb; 64 struct fiodname_args fa; 65 size_t used; 66 67 *buf = '\0'; 68 69 /* Must be a terminal. */ 70 if (!isatty(fd)) 71 return (ENOTTY); 72 /* Must be a character device. */ 73 if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode)) 74 return (ENOTTY); 75 /* Must have enough room */ 76 if (len <= sizeof(_PATH_DEV)) 77 return (ERANGE); 78 79 strcpy(buf, _PATH_DEV); 80 used = strlen(buf); 81 fa.len = len - used; 82 fa.name = buf + used; 83 if (_ioctl(fd, FIODNAME, &fa) == -1) { 84 #ifdef TTYNAME_DEVFS_COMPAT 85 /* If compat mode is set, fall back to old method */ 86 devname_r(sb.st_rdev, S_IFCHR, buf + used, len - used); 87 #else 88 return ERANGE; 89 #endif 90 } 91 return (0); 92 } 93 94 static void 95 ttyname_keycreate(void) 96 { 97 ttyname_keycreated = (thr_keycreate(&ttyname_key, free) == 0); 98 } 99 100 char * 101 ttyname(int fd) 102 { 103 char *buf; 104 105 if (thr_main() != 0) 106 buf = ttyname_buf; 107 else { 108 if (thr_once(&ttyname_init_once, ttyname_keycreate) != 0 || 109 !ttyname_keycreated) 110 return (NULL); 111 if ((buf = thr_getspecific(ttyname_key)) == NULL) { 112 if ((buf = malloc(sizeof ttyname_buf)) == NULL) 113 return (NULL); 114 if (thr_setspecific(ttyname_key, buf) != 0) { 115 free(buf); 116 return (NULL); 117 } 118 } 119 } 120 121 if (ttyname_r(fd, buf, sizeof ttyname_buf) != 0) 122 return (NULL); 123 return (buf); 124 } 125