gen/FreeBSD/ttyname.c

   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: src/lib/libc/gen/ttyname.c,v 1.16 2004/01/06 18:26:14 nectar Exp $");
  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 <errno.h>
  52 #include "un-namespace.h"
  53
  54 #include "libc_private.h"
  55
  56 #ifndef BUILDING_VARIANT
  57 static pthread_once_t ttyname_buf_control = PTHREAD_ONCE_INIT;
  58 static char *buf = NULL;
  59 static char *ttyname_threaded(int fd);
  60 static char *ttyname_unthreaded(int fd);
  61
  62 static pthread_mutex_t  ttyname_lock = PTHREAD_MUTEX_INITIALIZER;
  63 static pthread_key_t    ttyname_key;
  64 static int              ttyname_init = 0;
  65
  66 char *
  67 ttyname(int fd)
  68 {
  69         char           *ret;
  70
  71         if (__isthreaded == 0)
  72                 ret = ttyname_unthreaded(fd);
  73         else
  74                 ret = ttyname_threaded(fd);
  75         return (ret);
  76 }
  77 #endif /* !BUILDING_VARIANT */
  78
  79 #if __DARWIN_UNIX03
  80 int
  81 #else /* !__DARWIN_UNIX03 */
  82 char *
  83 #endif /* __DARWIN_UNIX03 */
  84 ttyname_r(int fd, char *thrbuf, size_t len)
  85 {
  86         struct stat     sb;
  87
  88 #if __DARWIN_UNIX03
  89         if (_fstat(fd, &sb) < 0)
  90                 return (EBADF);
  91         /* Must be a terminal. */
  92         if (!isatty(fd))
  93                 return (ENOTTY);
  94         /* Must be a character device. */
  95         if (!S_ISCHR(sb.st_mode))
  96                 return (ENOTTY);
  97         /* Must have enough room */
  98         if (len <= sizeof(_PATH_DEV))
  99                 return (ERANGE);
 100 #else /* !__DARWIN_UNIX03 */
 101         /* Must be a terminal. */
 102         if (!isatty(fd))
 103                 return (NULL);
 104         /* Must be a character device. */
 105         if (_fstat(fd, &sb))
 106                 return (NULL);
 107         if (!S_ISCHR(sb.st_mode)) {
 108                 errno = ENOTTY;
 109                 return (NULL);
 110         }
 111         /* Must have enough room */
 112         if (len <= sizeof(_PATH_DEV)) {
 113                 errno = ERANGE;
 114                 return (NULL);
 115         }
 116 #endif /* __DARWIN_UNIX03 */
 117
 118         strlcpy(thrbuf, _PATH_DEV, len);
 119         if (devname_r(sb.st_rdev, S_IFCHR,
 120             thrbuf + strlen(thrbuf), len - strlen(thrbuf)) == NULL)
 121 #if __DARWIN_UNIX03
 122                 return (ERANGE);
 123         return (0);
 124 #else /* !__DARWIN_UNIX03 */
 125         {
 126                 errno = ERANGE;
 127                 return (NULL);
 128         }
 129         return (thrbuf);
 130 #endif /* __DARWIN_UNIX03 */
 131 }
 132
 133 #ifndef BUILDING_VARIANT
 134 static char *
 135 ttyname_threaded(int fd)
 136 {
 137         char    *buf;
 138
 139         if (ttyname_init == 0) {
 140                 _pthread_mutex_lock(&ttyname_lock);
 141                 if (ttyname_init == 0) {
 142                         /* __PTK_LIBC_TTYNAME_KEY */
 143                         ttyname_key = __LIBC_PTHREAD_KEY_TTYNAME;
 144                         if (pthread_key_init_np(ttyname_key, free)) {
 145                                 int save = errno;
 146                                 _pthread_mutex_unlock(&ttyname_lock);
 147                                 errno = save;
 148                                 return (NULL);
 149                         }
 150                         ttyname_init = 1;
 151                 }
 152                 _pthread_mutex_unlock(&ttyname_lock);
 153         }
 154
 155         /* Must have thread specific data field to put data */
 156         if ((buf = _pthread_getspecific(ttyname_key)) == NULL) {
 157                 if ((buf = malloc(sizeof(_PATH_DEV) + MAXNAMLEN)) != NULL) {
 158                         if (_pthread_setspecific(ttyname_key, buf) != 0) {
 159                                 int save = errno;
 160                                 free(buf);
 161                                 errno = save;
 162                                 return (NULL);
 163                         }
 164                 } else {
 165                         return (NULL);
 166                 }
 167         }
 168 #if __DARWIN_UNIX03
 169         return (ttyname_r(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN) == 0 ? buf : NULL);
 170 #else /* !__DARWIN_UNIX03 */
 171         return (ttyname_r(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN));
 172 #endif /* __DARWIN_UNIX03 */
 173 }
 174
 175 static void
 176 ttyname_buf_allocate(void)
 177 {
 178         buf = malloc(sizeof(_PATH_DEV) + MAXNAMLEN);
 179 }
 180
 181 static char *
 182 ttyname_unthreaded(int fd)
 183 {
 184         struct stat     sb;
 185         struct termios  ttyb;
 186
 187         /* Must be a terminal. */
 188         if (tcgetattr(fd, &ttyb) < 0)
 189                 return (NULL);
 190         /* Must be a character device. */
 191         if (_fstat(fd, &sb))
 192                 return (NULL);
 193         if (!S_ISCHR(sb.st_mode)) {
 194                 errno = ENOTTY;
 195                 return (NULL);
 196         }
 197
 198         if (pthread_once(&ttyname_buf_control, ttyname_buf_allocate)
 199                 || !buf) {
 200                 errno = ENOMEM;
 201                 return (NULL);
 202         }
 203
 204         strlcpy(buf, _PATH_DEV, sizeof(_PATH_DEV) + MAXNAMLEN);
 205         if (devname_r(sb.st_rdev, S_IFCHR,
 206                 buf + strlen(buf), sizeof(_PATH_DEV) + MAXNAMLEN - strlen(buf)) == NULL) {
 207                 errno = ERANGE;
 208                 return (NULL);
 209         }
 210         return (buf);
 211 }
 212 #endif /* !BUILDING_VARIANT */