mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-10-30 10:45:40 +03:00 
			
		
		
		
	
		
			
				
	
	
		
			99 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			99 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 1993-2025 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>
 | |
| 
 | |
| FILE *
 | |
| freopen64 (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;
 | |
|   _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;
 | |
|   fp->_flags2 &= ~(_IO_FLAGS2_MMAP
 | |
| 		   | _IO_FLAGS2_NOTCANCEL
 | |
| 		   | _IO_FLAGS2_CLOEXEC);
 | |
|   fp->_mode = 0;
 | |
|   result = _IO_file_fopen (fp, gfilename, mode, 0);
 | |
|   fp->_flags2 &= ~_IO_FLAGS2_NOCLOSE;
 | |
|   if (result != NULL)
 | |
|     result = __fopen_maybe_mmap (result);
 | |
|   if (result != NULL)
 | |
|     {
 | |
|       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);
 | |
|   if (result == NULL && (fp->_flags & _IO_IS_FILEBUF) != 0)
 | |
|     _IO_deallocate_file (fp);
 | |
|   return result;
 | |
| }
 |