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-rw-r--r--csu/check_fds.c102
1 files changed, 0 insertions, 102 deletions
diff --git a/csu/check_fds.c b/csu/check_fds.c
deleted file mode 100644
index 10ba3da..0000000
--- a/csu/check_fds.c
+++ /dev/null
@@ -1,102 +0,0 @@
-/* Copyright (C) 2000, 2002, 2003, 2005 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 <fcntl.h>
-#include <paths.h>
-#include <unistd.h>
-#include <sys/stat.h>
-#include <sys/sysmacros.h>
-
-/* Try to get a machine dependent instruction which will make the
- program crash. This is used in case everything else fails. */
-#include <abort-instr.h>
-#ifndef ABORT_INSTRUCTION
-/* No such instruction is available. */
-# define ABORT_INSTRUCTION
-#endif
-
-#include <device-nrs.h>
-#include <not-cancel.h>
-
-
-/* Should other OSes (e.g., Hurd) have different versions which can
- be written in a better way? */
-static void
-check_one_fd (int fd, int mode)
-{
- /* Note that fcntl() with this parameter is not a cancellation point. */
- if (__builtin_expect (__libc_fcntl (fd, F_GETFD), 0) == -1
- && errno == EBADF)
- {
- const char *name;
- dev_t dev;
-
- /* For writable descriptors we use /dev/full. */
- if ((mode & O_ACCMODE) == O_WRONLY)
- {
- name = _PATH_DEV "full";
- dev = makedev (DEV_FULL_MAJOR, DEV_FULL_MINOR);
- }
- else
- {
- name = _PATH_DEVNULL;
- dev = makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR);
- }
-
- /* Something is wrong with this descriptor, it's probably not
- opened. Open /dev/null so that the SUID program we are
- about to start does not accidently use this descriptor. */
- int nullfd = open_not_cancel (name, mode, 0);
-
- /* We are very paranoid here. With all means we try to ensure
- that we are actually opening the /dev/null device and nothing
- else.
-
- Note that the following code assumes that STDIN_FILENO,
- STDOUT_FILENO, STDERR_FILENO are the three lowest file
- decsriptor numbers, in this order. */
- struct stat64 st;
- if (__builtin_expect (nullfd != fd, 0)
- || __builtin_expect (__fxstat64 (_STAT_VER, fd, &st), 0) != 0
- || __builtin_expect (S_ISCHR (st.st_mode), 1) == 0
- || st.st_rdev != dev)
- /* We cannot even give an error message here since it would
- run into the same problems. */
- while (1)
- /* Try for ever and ever. */
- ABORT_INSTRUCTION;
- }
-}
-
-
-void
-__libc_check_standard_fds (void)
-{
- /* This is really paranoid but some people actually are. If /dev/null
- should happen to be a symlink to somewhere else and not the device
- commonly known as "/dev/null" we bail out. We can detect this with
- the O_NOFOLLOW flag for open() but only on some system. */
-#ifndef O_NOFOLLOW
-# define O_NOFOLLOW 0
-#endif
- /* Check all three standard file descriptors. */
- check_one_fd (STDIN_FILENO, O_WRONLY | O_NOFOLLOW);
- check_one_fd (STDOUT_FILENO, O_RDONLY | O_NOFOLLOW);
- check_one_fd (STDERR_FILENO, O_RDONLY | O_NOFOLLOW);
-}