newlib-cygwin/newlib/libc/sys/linux/ttyname_r.c

193 lines
4.6 KiB
C

/* Copyright (C) 1991,92,93,1995-1999,2000,2001 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#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 <stdio.h>
#include <stdlib.h>
#include <machine/weakalias.h>
static int getttyname_r (char *buf, size_t buflen,
dev_t mydev, ino64_t myino, int save,
int *dostat);
extern struct dirent64 *__readdir64 (DIR *);
static int
getttyname_r (char *buf, size_t buflen, dev_t mydev, ino64_t myino,
int save, int *dostat)
{
struct stat64 st;
DIR *dirstream;
struct dirent64 *d;
size_t devlen = strlen (buf);
dirstream = opendir (buf);
if (dirstream == NULL)
{
*dostat = -1;
return errno;
}
while ((d = __readdir64 (dirstream)) != NULL)
{
if ((d->d_ino == myino || *dostat)
&& strcmp (d->d_name, "stdin")
&& strcmp (d->d_name, "stdout")
&& strcmp (d->d_name, "stderr"))
{
size_t needed = strlen (d->d_name) + 1;
if (needed > buflen)
{
*dostat = -1;
(void) closedir (dirstream);
__set_errno (ERANGE);
return ERANGE;
}
strncpy (buf + devlen, d->d_name, needed);
if (stat64 (buf, &st) == 0
#ifdef _STATBUF_ST_RDEV
&& S_ISCHR (st.st_mode) && st.st_rdev == mydev
#else
&& d->d_ino == myino && st.st_dev == mydev
#endif
)
{
(void) closedir (dirstream);
__set_errno (save);
return 0;
}
}
}
(void) closedir (dirstream);
__set_errno (save);
/* It is not clear what to return in this case. `isatty' says FD
refers to a TTY but no entry in /dev has this inode. */
return ENOTTY;
}
/* Store at most BUFLEN character of the pathname of the terminal FD is
open on in BUF. Return 0 on success, otherwise an error number. */
int
__ttyname_r (int fd, char *buf, size_t buflen)
{
char procname[30];
struct stat64 st, st1;
int dostat = 0;
int save = errno;
int ret;
/* Test for the absolute minimal size. This makes life easier inside
the loop. */
if (!buf)
{
__set_errno (EINVAL);
return EINVAL;
}
if (buflen < sizeof ("/dev/pts/"))
{
__set_errno (ERANGE);
return ERANGE;
}
if (!isatty (fd))
{
__set_errno (ENOTTY);
return ENOTTY;
}
/* We try using the /proc filesystem. */
sprintf (procname, "/proc/self/fd/%d", fd);
ret = readlink (procname, buf, buflen - 1);
if (ret != -1 && buf[0] != '[')
{
buf[ret] = '\0';
return 0;
}
if (ret == -1 && errno == ENAMETOOLONG)
{
__set_errno (ERANGE);
return ERANGE;
}
if (fstat64 (fd, &st) < 0)
return errno;
/* Prepare the result buffer. */
memcpy (buf, "/dev/pts/", sizeof ("/dev/pts/"));
buflen -= sizeof ("/dev/pts/") - 1;
if (stat64 (buf, &st1) == 0 && S_ISDIR (st1.st_mode))
{
#ifdef _STATBUF_ST_RDEV
ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino, save,
&dostat);
#else
ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino, save,
&dostat);
#endif
}
else
{
__set_errno (save);
ret = ENOENT;
}
if (ret && dostat != -1)
{
buf[sizeof ("/dev/") - 1] = '\0';
buflen += sizeof ("pts/") - 1;
#ifdef _STATBUF_ST_RDEV
ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino, save,
&dostat);
#else
ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino, save,
&dostat);
#endif
}
if (ret && dostat != -1)
{
buf[sizeof ("/dev/") - 1] = '\0';
dostat = 1;
#ifdef _STATBUF_ST_RDEV
ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino,
save, &dostat);
#else
ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino,
save, &dostat);
#endif
}
return ret;
}
weak_alias (__ttyname_r, ttyname_r)