| /* 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 <termios.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <stdlib.h> |
| |
| #include <_itoa.h> |
| #include <kernel-features.h> |
| |
| #if 0 |
| /* Is this used anywhere? It is not exported. */ |
| char *__ttyname; |
| #endif |
| |
| static char *getttyname (const char *dev, dev_t mydev, |
| ino64_t myino, int save, int *dostat) |
| internal_function; |
| |
| |
| libc_freeres_ptr (static char *getttyname_name); |
| |
| static char * |
| internal_function attribute_compat_text_section |
| getttyname (const char *dev, dev_t mydev, ino64_t myino, int save, int *dostat) |
| { |
| static size_t namelen; |
| struct stat64 st; |
| DIR *dirstream; |
| struct dirent64 *d; |
| size_t devlen = strlen (dev) + 1; |
| |
| dirstream = __opendir (dev); |
| if (dirstream == NULL) |
| { |
| *dostat = -1; |
| return NULL; |
| } |
| |
| /* Prepare for the loop. If we already have a buffer copy the directory |
| name we look at into it. */ |
| if (devlen < namelen) |
| *((char *) __mempcpy (getttyname_name, dev, devlen - 1)) = '/'; |
| |
| while ((d = __readdir64 (dirstream)) != NULL) |
| if ((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 (devlen + dlen > namelen) |
| { |
| free (getttyname_name); |
| namelen = 2 * (devlen + 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, devlen - 1)) = '/'; |
| } |
| memcpy (&getttyname_name[devlen], d->d_name, dlen); |
| if (__xstat64 (_STAT_VER, getttyname_name, &st) == 0 |
| #ifdef _STATBUF_ST_RDEV |
| && S_ISCHR (st.st_mode) && st.st_rdev == mydev |
| #else |
| && d->d_fileno == myino && st.st_dev == mydev |
| #endif |
| ) |
| { |
| (void) __closedir (dirstream); |
| #if 0 |
| __ttyname = getttyname_name; |
| #endif |
| __set_errno (save); |
| return getttyname_name; |
| } |
| } |
| |
| (void) __closedir (dirstream); |
| __set_errno (save); |
| return NULL; |
| } |
| |
| |
| /* Static buffer in `ttyname'. */ |
| libc_freeres_ptr (static char *ttyname_buf); |
| |
| |
| /* 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 (int fd) |
| { |
| static size_t buflen; |
| char procname[30]; |
| struct stat64 st, st1; |
| int dostat = 0; |
| char *name; |
| int save = errno; |
| struct termios term; |
| |
| /* isatty check, tcgetattr is used because it sets the correct |
| errno (EBADF resp. ENOTTY) on error. */ |
| if (__builtin_expect (__tcgetattr (fd, &term) < 0, 0)) |
| return NULL; |
| |
| if (__fxstat64 (_STAT_VER, fd, &st) < 0) |
| return NULL; |
| |
| /* We try using the /proc filesystem. */ |
| *_fitoa_word (fd, __stpcpy (procname, "/proc/self/fd/"), 10, 0) = '\0'; |
| |
| if (buflen == 0) |
| { |
| buflen = 4095; |
| ttyname_buf = (char *) malloc (buflen + 1); |
| if (ttyname_buf == NULL) |
| { |
| buflen = 0; |
| return NULL; |
| } |
| } |
| |
| ssize_t len = __readlink (procname, ttyname_buf, buflen); |
| if (__builtin_expect (len != -1, 1)) |
| { |
| if ((size_t) len >= buflen) |
| return NULL; |
| |
| #define UNREACHABLE_LEN strlen ("(unreachable)") |
| if (len > UNREACHABLE_LEN |
| && memcmp (ttyname_buf, "(unreachable)", UNREACHABLE_LEN) == 0) |
| { |
| memmove (ttyname_buf, ttyname_buf + UNREACHABLE_LEN, |
| len - UNREACHABLE_LEN); |
| len -= UNREACHABLE_LEN; |
| } |
| |
| /* readlink need not terminate the string. */ |
| ttyname_buf[len] = '\0'; |
| |
| /* Verify readlink result, fall back on iterating through devices. */ |
| if (ttyname_buf[0] == '/' |
| && __xstat64 (_STAT_VER, ttyname_buf, &st1) == 0 |
| #ifdef _STATBUF_ST_RDEV |
| && S_ISCHR (st1.st_mode) |
| && st1.st_rdev == st.st_rdev |
| #else |
| && st1.st_ino == st.st_ino |
| && st1.st_dev == st.st_dev |
| #endif |
| ) |
| return ttyname_buf; |
| } |
| |
| if (__xstat64 (_STAT_VER, "/dev/pts", &st1) == 0 && S_ISDIR (st1.st_mode)) |
| { |
| #ifdef _STATBUF_ST_RDEV |
| name = getttyname ("/dev/pts", st.st_rdev, st.st_ino, save, &dostat); |
| #else |
| name = getttyname ("/dev/pts", st.st_dev, st.st_ino, save, &dostat); |
| #endif |
| } |
| else |
| { |
| __set_errno (save); |
| name = NULL; |
| } |
| |
| if (!name && dostat != -1) |
| { |
| #ifdef _STATBUF_ST_RDEV |
| name = getttyname ("/dev", st.st_rdev, st.st_ino, save, &dostat); |
| #else |
| name = getttyname ("/dev", st.st_dev, st.st_ino, save, &dostat); |
| #endif |
| } |
| |
| if (!name && dostat != -1) |
| { |
| dostat = 1; |
| #ifdef _STATBUF_ST_RDEV |
| name = getttyname ("/dev", st.st_rdev, st.st_ino, save, &dostat); |
| #else |
| name = getttyname ("/dev", st.st_dev, st.st_ino, save, &dostat); |
| #endif |
| } |
| |
| return name; |
| } |