78 lines
2.2 KiB
C
78 lines
2.2 KiB
C
/* Copyright (C) 1991, 1992 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 Library General Public License as
|
|
published by the Free Software Foundation; either version 2 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
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
|
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
#include <ansidecl.h>
|
|
#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>
|
|
|
|
|
|
char *__ttyname = 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 *
|
|
DEFUN(ttyname, (fd), int fd)
|
|
{
|
|
static char dev[] = "/dev";
|
|
char name[NAME_MAX];
|
|
char *CONST np = &name[sizeof(dev)];
|
|
struct stat st;
|
|
dev_t mydev;
|
|
ino_t myino;
|
|
DIR *dirstream;
|
|
struct dirent *d;
|
|
|
|
if (fstat(fd, &st) < 0)
|
|
return NULL;
|
|
if (!S_ISCHR(st.st_mode))
|
|
{
|
|
errno = EINVAL;
|
|
return NULL;
|
|
}
|
|
mydev = st.st_dev;
|
|
myino = st.st_ino;
|
|
|
|
dirstream = opendir(dev);
|
|
if (dirstream == NULL)
|
|
return NULL;
|
|
|
|
(void) memcpy(name, dev, sizeof(dev) - 1);
|
|
np[-1] = '/';
|
|
while ((d = readdir(dirstream)) != NULL)
|
|
if (d->d_fileno == myino)
|
|
{
|
|
(void) memcpy(np, d->d_name, d->d_namlen + 1);
|
|
if (stat(name, &st) == 0 && st.st_dev == mydev)
|
|
{
|
|
static char result[sizeof (dev) + NAME_MAX];
|
|
(void) memcpy(result, name, (np - name) + d->d_namlen + 1);
|
|
(void) closedir(dirstream);
|
|
__ttyname = result;
|
|
return result;
|
|
}
|
|
}
|
|
(void) closedir(dirstream);
|
|
return NULL;
|
|
}
|