Exemple #1
0
_IO_FILE *
_IO_new_fdopen (int fd, const char *mode)
{
  int read_write;
  struct locked_FILE
  {
    struct _IO_FILE_plus fp;
#ifdef _IO_MTSAFE_IO
    _IO_lock_t lock;
#endif
    struct _IO_wide_data wd;
  } *new_f;
  int i;
  int use_mmap = 0;

  /* Decide whether we modify the offset of the file we attach to and seek to
     the end of file.  We only do this if the mode is 'a' and if the file
     descriptor did not have O_APPEND in its flags already.  */
  bool do_seek = false;

  switch (*mode)
    {
    case 'r':
      read_write = _IO_NO_WRITES;
      break;
    case 'w':
      read_write = _IO_NO_READS;
      break;
    case 'a':
      read_write = _IO_NO_READS|_IO_IS_APPENDING;
      break;
    default:
      MAYBE_SET_EINVAL;
      return NULL;
  }
  for (i = 1; i < 5; ++i)
    {
      switch (*++mode)
	{
	case '\0':
	  break;
	case '+':
	  read_write &= _IO_IS_APPENDING;
	  break;
	case 'm':
	  use_mmap = 1;
	  continue;
	case 'x':
	case 'b':
	default:
	  /* Ignore */
	  continue;
	}
      break;
    }
#ifdef F_GETFL
  int fd_flags = _IO_fcntl (fd, F_GETFL);
#ifndef O_ACCMODE
#define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR)
#endif
  if (fd_flags == -1)
    return NULL;

  if (((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES))
      || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS)))
    {
      MAYBE_SET_EINVAL;
      return NULL;
    }

  /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b)
     [System Application Program Interface (API) Amendment 1:
     Realtime Extensions], Rationale B.8.3.3
     Open a Stream on a File Descriptor says:

	 Although not explicitly required by POSIX.1, a good
	 implementation of append ("a") mode would cause the
	 O_APPEND flag to be set.

     (Historical implementations [such as Solaris2] do a one-time
     seek in fdopen.)

     However, we do not turn O_APPEND off if the mode is "w" (even
     though that would seem consistent) because that would be more
     likely to break historical programs.
     */
  if ((read_write & _IO_IS_APPENDING) && !(fd_flags & O_APPEND))
    {
      do_seek = true;
#ifdef F_SETFL
      if (_IO_fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1)
#endif
	return NULL;
    }
#endif

  new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
  if (new_f == NULL)
    return NULL;
#ifdef _IO_MTSAFE_IO
  new_f->fp.file._lock = &new_f->lock;
#endif
  _IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd,
#ifdef _G_HAVE_MMAP
	       (use_mmap && (read_write & _IO_NO_WRITES))
	       ? &_IO_wfile_jumps_maybe_mmap :
#endif
	       &_IO_wfile_jumps);
  _IO_JUMPS (&new_f->fp) =
#ifdef _G_HAVE_MMAP
    (use_mmap && (read_write & _IO_NO_WRITES)) ? &_IO_file_jumps_maybe_mmap :
#endif
      &_IO_file_jumps;
  _IO_new_file_init_internal (&new_f->fp);
#if  !_IO_UNIFIED_JUMPTABLES
  new_f->fp.vtable = NULL;
#endif
  /* We only need to record the fd because _IO_file_init_internal will
     have unset the offset.  It is important to unset the cached
     offset because the real offset in the file could change between
     now and when the handle is activated and we would then mislead
     ftell into believing that we have a valid offset.  */
  new_f->fp.file._fileno = fd;
  new_f->fp.file._flags &= ~_IO_DELETE_DONT_CLOSE;

  _IO_mask_flags (&new_f->fp.file, read_write,
		  _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);

  /* For append mode, set the file offset to the end of the file if we added
     O_APPEND to the file descriptor flags.  Don't update the offset cache
     though, since the file handle is not active.  */
  if (do_seek && ((read_write & (_IO_IS_APPENDING | _IO_NO_READS))
		  == (_IO_IS_APPENDING | _IO_NO_READS)))
    {
      _IO_off64_t new_pos = _IO_SYSSEEK (&new_f->fp.file, 0, _IO_seek_end);
      if (new_pos == _IO_pos_BAD && errno != ESPIPE)
	return NULL;
    }
  return &new_f->fp.file;
}
Exemple #2
0
attribute_compat_text_section
_IO_old_fdopen (int fd, const char *mode)
{
  int read_write;
  int posix_mode = 0;
  struct locked_FILE
  {
    struct _IO_FILE_complete_plus fp;
#ifdef _IO_MTSAFE_IO
    _IO_lock_t lock;
#endif
  } *new_f;
  int fd_flags;

  switch (*mode++)
    {
    case 'r':
      read_write = _IO_NO_WRITES;
      break;
    case 'w':
      read_write = _IO_NO_READS;
      break;
    case 'a':
      posix_mode = O_APPEND;
      read_write = _IO_NO_READS|_IO_IS_APPENDING;
      break;
    default:
      MAYBE_SET_EINVAL;
      return NULL;
  }
  if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
    read_write &= _IO_IS_APPENDING;
#ifdef F_GETFL
  fd_flags = _IO_fcntl (fd, F_GETFL);
#ifndef O_ACCMODE
#define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR)
#endif
  if (fd_flags == -1
      || ((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES))
      || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS)))
    return NULL;

  /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b)
     [System Application Program Interface (API) Amendment 1:
     Realtime Extensions], Rationale B.8.3.3
     Open a Stream on a File Descriptor says:

         Although not explicitly required by POSIX.1, a good
         implementation of append ("a") mode would cause the
         O_APPEND flag to be set.

     (Historical implementations [such as Solaris2] do a one-time
     seek in fdopen.)

     However, we do not turn O_APPEND off if the mode is "w" (even
     though that would seem consistent) because that would be more
     likely to break historical programs.
     */
  if ((posix_mode & O_APPEND) && !(fd_flags & O_APPEND))
    {
#ifdef F_SETFL
      if (_IO_fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1)
#endif
	return NULL;
    }
#endif

  new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
  if (new_f == NULL)
    return NULL;
#ifdef _IO_MTSAFE_IO
  new_f->fp.file._file._lock = &new_f->lock;
#endif
  _IO_old_init (&new_f->fp.file._file, 0);
  _IO_JUMPS_FILE_plus (&new_f->fp) = &_IO_old_file_jumps;
  _IO_old_file_init ((struct _IO_FILE_plus *) &new_f->fp);
#if  !_IO_UNIFIED_JUMPTABLES
  new_f->fp.vtable = NULL;
#endif
  if (_IO_old_file_attach (&new_f->fp.file._file, fd) == NULL)
    {
      _IO_un_link ((struct _IO_FILE_plus *) &new_f->fp);
      free (new_f);
      return NULL;
    }
  new_f->fp.file._file._flags &= ~_IO_DELETE_DONT_CLOSE;

  _IO_mask_flags (&new_f->fp.file._file, read_write,
		  _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);

  return (_IO_FILE *) &new_f->fp;
}