mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 04:50:07 +00:00
113 lines
3.7 KiB
C
113 lines
3.7 KiB
C
/* Copyright (C) 1993-2024 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
|
|
<https://www.gnu.org/licenses/>.
|
|
|
|
As a special exception, if you link the code in this file with
|
|
files compiled with a GNU compiler to produce an executable,
|
|
that does not cause the resulting executable to be covered by
|
|
the GNU Lesser General Public License. This exception does not
|
|
however invalidate any other reasons why the executable file
|
|
might be covered by the GNU Lesser General Public License.
|
|
This exception applies to code released by its copyright holders
|
|
in files containing the exception. */
|
|
|
|
#include <stdio.h>
|
|
#include <fcntl.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#include <libioP.h>
|
|
#include <fd_to_filename.h>
|
|
#include <shlib-compat.h>
|
|
|
|
FILE *
|
|
freopen (const char *filename, const char *mode, FILE *fp)
|
|
{
|
|
FILE *result = NULL;
|
|
struct fd_to_filename fdfilename;
|
|
|
|
CHECK_FILE (fp, NULL);
|
|
|
|
_IO_acquire_lock (fp);
|
|
/* First flush the stream (failure should be ignored). */
|
|
_IO_SYNC (fp);
|
|
|
|
if (!(fp->_flags & _IO_IS_FILEBUF))
|
|
goto end;
|
|
|
|
int fd = _IO_fileno (fp);
|
|
const char *gfilename
|
|
= filename != NULL ? filename : __fd_to_filename (fd, &fdfilename);
|
|
|
|
fp->_flags2 |= _IO_FLAGS2_NOCLOSE;
|
|
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
|
|
if (&_IO_stdin_used == NULL)
|
|
{
|
|
/* If the shared C library is used by the application binary which
|
|
was linked against the older version of libio, we just use the
|
|
older one even for internal use to avoid trouble since a pointer
|
|
to the old libio may be passed into shared C library and wind
|
|
up here. */
|
|
_IO_old_file_close_it (fp);
|
|
_IO_JUMPS_FUNC_UPDATE (fp, &_IO_old_file_jumps);
|
|
result = _IO_old_file_fopen (fp, gfilename, mode);
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
_IO_file_close_it (fp);
|
|
_IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps;
|
|
if (_IO_vtable_offset (fp) == 0 && fp->_wide_data != NULL)
|
|
fp->_wide_data->_wide_vtable = &_IO_wfile_jumps;
|
|
result = _IO_file_fopen (fp, gfilename, mode, 1);
|
|
if (result != NULL)
|
|
result = __fopen_maybe_mmap (result);
|
|
}
|
|
fp->_flags2 &= ~_IO_FLAGS2_NOCLOSE;
|
|
if (result != NULL)
|
|
{
|
|
/* unbound stream orientation */
|
|
result->_mode = 0;
|
|
|
|
if (fd != -1 && _IO_fileno (result) != fd)
|
|
{
|
|
/* At this point we have both file descriptors already allocated,
|
|
so __dup3 will not fail with EBADF, EINVAL, or EMFILE. But
|
|
we still need to check for EINVAL and, due Linux internal
|
|
implementation, EBUSY. It is because on how it internally opens
|
|
the file by splitting the buffer allocation operation and VFS
|
|
opening (a dup operation may run when a file is still pending
|
|
'install' on VFS). */
|
|
if (__dup3 (_IO_fileno (result), fd,
|
|
(result->_flags2 & _IO_FLAGS2_CLOEXEC) != 0
|
|
? O_CLOEXEC : 0) == -1)
|
|
{
|
|
_IO_file_close_it (result);
|
|
result = NULL;
|
|
goto end;
|
|
}
|
|
__close (_IO_fileno (result));
|
|
_IO_fileno (result) = fd;
|
|
}
|
|
}
|
|
else if (fd != -1)
|
|
__close (fd);
|
|
|
|
end:
|
|
_IO_release_lock (fp);
|
|
return result;
|
|
}
|