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 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char sccsid[] = "@(#)ttyname.c 8.2 (Berkeley) 1/27/94"; 32 #endif /* LIBC_SCCS and not lint */ 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include "namespace.h" 37 #include <sys/types.h> 38 #include <sys/ioctl.h> 39 #include <sys/filio.h> 40 #include <fcntl.h> 41 #include <dirent.h> 42 #include <stdlib.h> 43 #include <termios.h> 44 #include <unistd.h> 45 #include <string.h> 46 #include <paths.h> 47 #include <errno.h> 48 #include "reentrant.h" 49 #include "un-namespace.h" 50 51 #include "libc_private.h" 52 53 static char ttyname_buf[sizeof(_PATH_DEV) + MAXNAMLEN]; 54 55 static once_t ttyname_init_once = ONCE_INITIALIZER; 56 static thread_key_t ttyname_key; 57 static int ttyname_keycreated = 0; 58 59 int 60 ttyname_r(int fd, char *buf, size_t len) 61 { 62 size_t used; 63 64 *buf = '\0'; 65 66 /* Must be a terminal. */ 67 if (!isatty(fd)) 68 return (ENOTTY); 69 /* Must have enough room */ 70 if (len <= sizeof(_PATH_DEV)) 71 return (ERANGE); 72 73 strcpy(buf, _PATH_DEV); 74 used = strlen(buf); 75 if (fdevname_r(fd, buf + used, len - used) == NULL) 76 return (ENOTTY); 77 return (0); 78 } 79 80 static void 81 ttyname_keycreate(void) 82 { 83 ttyname_keycreated = (thr_keycreate(&ttyname_key, free) == 0); 84 } 85 86 char * 87 ttyname(int fd) 88 { 89 char *buf; 90 91 if (thr_main() != 0) 92 buf = ttyname_buf; 93 else { 94 if (thr_once(&ttyname_init_once, ttyname_keycreate) != 0 || 95 !ttyname_keycreated) 96 return (NULL); 97 if ((buf = thr_getspecific(ttyname_key)) == NULL) { 98 if ((buf = malloc(sizeof ttyname_buf)) == NULL) 99 return (NULL); 100 if (thr_setspecific(ttyname_key, buf) != 0) { 101 free(buf); 102 return (NULL); 103 } 104 } 105 } 106 107 if (ttyname_r(fd, buf, sizeof ttyname_buf) != 0) 108 return (NULL); 109 return (buf); 110 } 111