genops.c

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    return fp;
}

_IO_pos_t
_IO_default_seekpos (fp, pos, mode)
     _IO_FILE *fp;
     _IO_pos_t pos;
     int mode;
{
  return _IO_SEEKOFF (fp, _IO_pos_as_off (pos), 0, mode);
}

int
_IO_default_doallocate (fp)
     _IO_FILE *fp;
{
  char *buf;

  ALLOC_BUF (buf, _IO_BUFSIZ, EOF);
  _IO_setb (fp, buf, buf+_IO_BUFSIZ, 1);
  return 1;
}

void
_IO_init (fp, flags)
     _IO_FILE *fp;
     int flags;
{
  fp->_flags = _IO_MAGIC|flags;
  fp->_IO_buf_base = NULL;
  fp->_IO_buf_end = NULL;
  fp->_IO_read_base = NULL;
  fp->_IO_read_ptr = NULL;
  fp->_IO_read_end = NULL;
  fp->_IO_write_base = NULL;
  fp->_IO_write_ptr = NULL;
  fp->_IO_write_end = NULL;
  fp->_chain = NULL; /* Not necessary. */

  fp->_IO_save_base = NULL;
  fp->_IO_backup_base = NULL;
  fp->_IO_save_end = NULL;
  fp->_markers = NULL;
  fp->_cur_column = 0;
#ifdef _IO_MTSAFE_IO
  _IO_lock_init (*fp->_lock);
#endif
}

int
_IO_default_sync (fp)
     _IO_FILE *fp;
{
  return 0;
}

/* The way the C++ classes are mapped into the C functions in the
   current implementation, this function can get called twice! */

void
_IO_default_finish (fp, dummy)
     _IO_FILE *fp;
     int dummy;
{
  struct _IO_marker *mark;
  if (fp->_IO_buf_base && !(fp->_flags & _IO_USER_BUF))
    {
      FREE_BUF (fp->_IO_buf_base, _IO_blen (fp));
      fp->_IO_buf_base = fp->_IO_buf_end = NULL;
    }

  for (mark = fp->_markers; mark != NULL; mark = mark->_next)
    mark->_sbuf = NULL;

  if (fp->_IO_save_base)
    {
      free (fp->_IO_save_base);
      fp->_IO_save_base = NULL;
    }

#ifdef _IO_MTSAFE_IO
  _IO_lock_fini (*fp->_lock);
#endif

  _IO_un_link (fp);
}

_IO_pos_t
_IO_default_seekoff (fp, offset, dir, mode)
     _IO_FILE *fp;
     _IO_off_t offset;
     int dir;
     int mode;
{
    return _IO_pos_BAD;
}

int
_IO_sputbackc (fp, c)
     _IO_FILE *fp;
     int c;
{
  int result;

  if (fp->_IO_read_ptr > fp->_IO_read_base
      && (unsigned char)fp->_IO_read_ptr[-1] == (unsigned char)c)
    {
      fp->_IO_read_ptr--;
      result = (unsigned char) c;
    }
  else
    result = _IO_PBACKFAIL (fp, c);

  if (result != EOF)
    fp->_flags &= ~_IO_EOF_SEEN;

  return result;
}

int
_IO_sungetc (fp)
     _IO_FILE *fp;
{
  int result;

  if (fp->_IO_read_ptr > fp->_IO_read_base)
    {
      fp->_IO_read_ptr--;
      result = (unsigned char) *fp->_IO_read_ptr;
    }
  else
    result = _IO_PBACKFAIL (fp, EOF);

  if (result != EOF)
    fp->_flags &= ~_IO_EOF_SEEN;

  return result;
}

#if 0 /* Work in progress */
/* Seems not to be needed.  */
#if 0
void
_IO_set_column (fp, c)
     _IO_FILE *fp;
     int c;
{
  if (c == -1)
    fp->_column = -1;
  else
    fp->_column = c - (fp->_IO_write_ptr - fp->_IO_write_base);
}
#else
int
_IO_set_column (fp, i)
     _IO_FILE *fp;
     int i;
{
  fp->_cur_column = i + 1;
  return 0;
}
#endif
#endif


unsigned
_IO_adjust_column (start, line, count)
     unsigned start;
     const char *line;
     int count;
{
  const char *ptr = line + count;
  while (ptr > line)
    if (*--ptr == '\n')
      return line + count - ptr - 1;
  return start + count;
}

#if 0
/* Seems not to be needed. --drepper */
int
_IO_get_column (fp)
     _IO_FILE *fp;
{
  if (fp->_cur_column)
    return _IO_adjust_column (fp->_cur_column - 1,
			      fp->_IO_write_base,
			      fp->_IO_write_ptr - fp->_IO_write_base);
  return -1;
}
#endif

int
_IO_flush_all ()
{
  int result = 0;
  _IO_FILE *fp;
  for (fp = _IO_list_all; fp != NULL; fp = fp->_chain)
    if (fp->_IO_write_ptr > fp->_IO_write_base
	&& _IO_OVERFLOW (fp, EOF) == EOF)
      result = EOF;
  return result;
}

void
_IO_flush_all_linebuffered ()
{
  _IO_FILE *fp;
  for (fp = _IO_list_all; fp != NULL; fp = fp->_chain)
    if ((fp->_flags & _IO_NO_WRITES) == 0 && fp->_flags & _IO_LINE_BUF)
      _IO_OVERFLOW (fp, EOF);
}

static void _IO_unbuffer_all __P ((void));

static void
_IO_unbuffer_all ()
{
  _IO_FILE *fp;
  for (fp = _IO_list_all; fp != NULL; fp = fp->_chain)
    if (! (fp->_flags & _IO_UNBUFFERED))
      _IO_SETBUF (fp, NULL, 0);
}

void
_IO_cleanup ()
{
  _IO_flush_all ();

  /* We currently don't have a reliable mechanism for making sure that
     C++ static destructors are executed in the correct order.
     So it is possible that other static destructors might want to
     write to cout - and they're supposed to be able to do so.

     The following will make the standard streambufs be unbuffered,
     which forces any output from late destructors to be written out. */
  _IO_unbuffer_all ();
}

void
_IO_init_marker (marker, fp)
     struct _IO_marker *marker;
     _IO_FILE *fp;
{
  marker->_sbuf = fp;
  if (_IO_in_put_mode (fp))
    _IO_switch_to_get_mode (fp);
  if (_IO_in_backup (fp))
    marker->_pos = fp->_IO_read_ptr - fp->_IO_read_end;
  else
    marker->_pos = fp->_IO_read_ptr - fp->_IO_read_base;

  /* Should perhaps sort the chain? */
  marker->_next = fp->_markers;
  fp->_markers = marker;
}

void
_IO_remove_marker (marker)
     struct _IO_marker *marker;
{
  /* Unlink from sb's chain. */
  struct _IO_marker **ptr = &marker->_sbuf->_markers;
  for (; ; ptr = &(*ptr)->_next)
    {
      if (*ptr == NULL)
	break;
      else if (*ptr == marker)
	{
	  *ptr = marker->_next;
	  return;
	}
    }
#if 0
    if _sbuf has a backup area that is no longer needed, should we delete
    it now, or wait until the next underflow?
#endif
}

#define BAD_DELTA EOF

int
_IO_marker_difference (mark1, mark2)
     struct _IO_marker *mark1;
     struct _IO_marker *mark2;
{
  return mark1->_pos - mark2->_pos;
}

/* Return difference between MARK and current position of MARK's stream. */
int
_IO_marker_delta (mark)
     struct _IO_marker *mark;
{
  int cur_pos;
  if (mark->_sbuf == NULL)
    return BAD_DELTA;
  if (_IO_in_backup (mark->_sbuf))
    cur_pos = mark->_sbuf->_IO_read_ptr - mark->_sbuf->_IO_read_end;
  else
    cur_pos = mark->_sbuf->_IO_read_ptr - mark->_sbuf->_IO_read_base;
  return mark->_pos - cur_pos;
}

int
_IO_seekmark (fp, mark, delta)
     _IO_FILE *fp;
     struct _IO_marker *mark;
     int delta;
{
  if (mark->_sbuf != fp)
    return EOF;
 if (mark->_pos >= 0)
    {
      if (_IO_in_backup (fp))
	_IO_switch_to_main_get_area (fp);
      fp->_IO_read_ptr = fp->_IO_read_base + mark->_pos;
    }
  else
    {
      if (!_IO_in_backup (fp))
	_IO_switch_to_backup_area (fp);
      fp->_IO_read_ptr = fp->_IO_read_end + mark->_pos;
    }
  return 0;
}

void
_IO_unsave_markers (fp)
     _IO_FILE *fp;
{
  struct _IO_marker *mark = fp->_markers;
  if (mark)
    {
#ifdef TODO
      streampos offset = seekoff (0, ios::cur, ios::in);
      if (offset != EOF)
	{
	  offset += eGptr () - Gbase ();
	  for ( ; mark != NULL; mark = mark->_next)
	    mark->set_streampos (mark->_pos + offset);
	}
    else
      {
	for ( ; mark != NULL; mark = mark->_next)
	  mark->set_streampos (EOF);
      }
#endif
      fp->_markers = 0;
    }

  if (_IO_have_backup (fp))
    _IO_free_backup_area (fp);
}

#if 0
/* Seems not to be needed. --drepper */
int
_IO_nobackup_pbackfail (fp, c)
     _IO_FILE *fp;
     int c;
{
  if (fp->_IO_read_ptr > fp->_IO_read_base)
	fp->_IO_read_ptr--;
  if (c != EOF && *fp->_IO_read_ptr != c)
      *fp->_IO_read_ptr = c;
  return (unsigned char) c;
}
#endif

int
_IO_default_pbackfail (fp, c)
     _IO_FILE *fp;
     int c;
{
  if (fp->_IO_read_ptr <= fp->_IO_read_base)
    {
      /* Need to handle a filebuf in write mode (switch to read mode). FIXME!*/
      if (_IO_have_backup (fp) && !_IO_in_backup (fp))
	_IO_switch_to_backup_area (fp);

      if (!_IO_have_backup (fp))
	{
	  /* No backup buffer: allocate one. */
	  /* Use nshort buffer, if unused? (probably not)  FIXME */
	  int backup_size = 128;
	  char *bbuf = (char *) malloc (backup_size);
	  if (bbuf == NULL)
	    return EOF;
	  fp->_IO_save_base = bbuf;
	  fp->_IO_save_end = fp->_IO_save_base + backup_size;
	  fp->_IO_backup_base = fp->_IO_save_end;
	  _IO_switch_to_backup_area (fp);
	}
      else if (fp->_IO_read_ptr <= fp->_IO_read_base)
	{
	  /* Increase size of existing backup buffer. */
	  _IO_size_t new_size;
	  _IO_size_t old_size = fp->_IO_read_end - fp->_IO_read_base;
	  char *new_buf;
	  new_size = 2 * old_size;
	  new_buf = (char *) malloc (new_size);
	  if (new_buf == NULL)
	    return EOF;
	  memcpy (new_buf + (new_size - old_size), fp->_IO_read_base,
		  old_size);
	  free (fp->_IO_read_base);
	  _IO_setg (fp, new_buf, new_buf + (new_size - old_size),
		    new_buf + new_size);
	  fp->_IO_backup_base = fp->_IO_read_ptr;
	}
    }
  --fp->_IO_read_ptr;
  if (c != EOF && *fp->_IO_read_ptr != c)
    *fp->_IO_read_ptr = c;
  return (unsigned char) *fp->_IO_read_ptr;
}

_IO_pos_t
_IO_default_seek (fp, offset, dir)
     _IO_FILE *fp;
     _IO_off_t offset;
     int dir;
{
  return _IO_pos_BAD;
}

int
_IO_default_stat (fp, st)
     _IO_FILE *fp;
     void* st;
{
  return EOF;
}

_IO_ssize_t
_IO_default_read (fp, data, n)
     _IO_FILE* fp;
     void *data;
     _IO_ssize_t n;
{
  return -1;
}

_IO_ssize_t
_IO_default_write (fp, data, n)
     _IO_FILE *fp;
     const void *data;
     _IO_ssize_t n;
{
  return 0;
}


#ifdef TODO
#if defined(linux)
#define IO_CLEANUP ;
#endif

#ifdef IO_CLEANUP
  IO_CLEANUP
#else
struct __io_defs {
    __io_defs() { }
    ~__io_defs() { _IO_cleanup (); }
};
__io_defs io_defs__;
#endif

#endif /* TODO */

#ifdef weak_alias
weak_alias (_IO_cleanup, _cleanup)
#endif

#ifdef text_set_element
text_set_element(__libc_atexit, _cleanup);
#endif