| /* Copyright (C) 1991-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <errno.h> |
| #include <limits.h> |
| #include <stddef.h> |
| #include <dirent.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <stdlib.h> |
| |
| char *__ttyname; |
| |
| static char *getttyname (int fd, dev_t mydev, ino_t myino, |
| int save, int *dostat) internal_function; |
| |
| |
| libc_freeres_ptr (static char *getttyname_name); |
| |
| static char * |
| internal_function |
| getttyname (fd, mydev, myino, save, dostat) |
| int fd; |
| dev_t mydev; |
| ino_t myino; |
| int save; |
| int *dostat; |
| { |
| static const char dev[] = "/dev"; |
| static size_t namelen; |
| struct stat st; |
| DIR *dirstream; |
| struct dirent *d; |
| |
| dirstream = __opendir (dev); |
| if (dirstream == NULL) |
| { |
| *dostat = -1; |
| return NULL; |
| } |
| |
| while ((d = __readdir (dirstream)) != NULL) |
| if (((ino_t) d->d_fileno == myino || *dostat) |
| && strcmp (d->d_name, "stdin") |
| && strcmp (d->d_name, "stdout") |
| && strcmp (d->d_name, "stderr")) |
| { |
| size_t dlen = _D_ALLOC_NAMLEN (d); |
| if (sizeof (dev) + dlen > namelen) |
| { |
| free (getttyname_name); |
| namelen = 2 * (sizeof (dev) + dlen); /* Big enough. */ |
| getttyname_name = malloc (namelen); |
| if (! getttyname_name) |
| { |
| *dostat = -1; |
| /* Perhaps it helps to free the directory stream buffer. */ |
| (void) __closedir (dirstream); |
| return NULL; |
| } |
| *((char *) __mempcpy (getttyname_name, dev, sizeof (dev) - 1)) |
| = '/'; |
| } |
| (void) __mempcpy (&getttyname_name[sizeof (dev)], d->d_name, dlen); |
| if (stat (getttyname_name, &st) == 0 |
| #ifdef _STATBUF_ST_RDEV |
| && S_ISCHR (st.st_mode) && st.st_rdev == mydev |
| #else |
| && (ino_t) d->d_fileno == myino && st.st_dev == mydev |
| #endif |
| ) |
| { |
| (void) __closedir (dirstream); |
| __ttyname = getttyname_name; |
| __set_errno (save); |
| return getttyname_name; |
| } |
| } |
| |
| (void) __closedir (dirstream); |
| __set_errno (save); |
| return NULL; |
| } |
| |
| /* Return the pathname of the terminal FD is open on, or NULL on errors. |
| The returned storage is good only until the next call to this function. */ |
| char * |
| ttyname (fd) |
| int fd; |
| { |
| struct stat st; |
| int dostat = 0; |
| char *name; |
| int save = errno; |
| |
| if (!__isatty (fd)) |
| return NULL; |
| |
| if (fstat (fd, &st) < 0) |
| return NULL; |
| |
| #ifdef _STATBUF_ST_RDEV |
| name = getttyname (fd, st.st_rdev, st.st_ino, save, &dostat); |
| #else |
| name = getttyname (fd, st.st_dev, st.st_ino, save, &dostat); |
| #endif |
| |
| if (!name && dostat != -1) |
| { |
| dostat = 1; |
| #ifdef _STATBUF_ST_RDEV |
| name = getttyname (fd, st.st_rdev, st.st_ino, save, &dostat); |
| #else |
| name = getttyname (fd, st.st_dev, st.st_ino, save, &dostat); |
| #endif |
| } |
| |
| return name; |
| } |