diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/ttyname.c')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/ttyname.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/ttyname.c b/REORG.TODO/sysdeps/unix/sysv/linux/ttyname.c new file mode 100644 index 0000000000..5909cb765f --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/ttyname.c @@ -0,0 +1,223 @@ +/* Copyright (C) 1991-2017 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 "ttyname.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 (__glibc_unlikely (__tcgetattr (fd, &term) < 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 (__glibc_likely (len != -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 +#endif + && st1.st_ino == st.st_ino + && st1.st_dev == st.st_dev) + return ttyname_buf; + + /* If the link doesn't exist, then it points to a device in another + namespace. */ + if (is_pty (&st)) + { + __set_errno (ENODEV); + return NULL; + } + } + + 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; +} |