frm_driver.c

ncurses 库 可能有用酒用 没用就算了 我觉得还可以用

  assert(buf && blen >= 0);
  while ((p > buf) && !ISBLANK(p[-1]))
    p--;
  return (p);
}

/* Set this to 1 to use the div_t version. This is a good idea if your
   compiler has an intrinsic div() support. Unfortunately GNU-C has it
   not yet.
   N.B.: This only works if form->curcol follows immediately form->currow
         and both are of type int.
*/
#define USE_DIV_T (0)

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static void Adjust_Cursor_Position(
|                                       FORM * form, const char * pos)
|
|   Description   :  Set current row and column of the form to values
|                    corresponding to the buffer position.
|
|   Return Values :  -
+--------------------------------------------------------------------------*/
INLINE static void
Adjust_Cursor_Position(FORM *form, const FIELD_CELL *pos)
{
  FIELD *field;
  int idx;

  field = form->current;
  assert(pos >= field->buf && field->dcols > 0);
  idx = (int)(pos - field->buf);
#if USE_DIV_T
  *((div_t *) & (form->currow)) = div(idx, field->dcols);
#else
  form->currow = idx / field->dcols;
  form->curcol = idx - field->cols * form->currow;
#endif
  if (field->drows < form->currow)
    form->currow = 0;
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static void Buffer_To_Window(
|                                      const FIELD  * field,
|                                      WINDOW * win)
|
|   Description   :  Copy the buffer to the window. If it is a multi-line
|                    field, the buffer is split to the lines of the
|                    window without any editing.
|
|   Return Values :  -
+--------------------------------------------------------------------------*/
static void
Buffer_To_Window(const FIELD *field, WINDOW *win)
{
  int width, height;
  int y, x;
  int len;
  int row;
  FIELD_CELL *pBuffer;

  assert(win && field);

  getyx(win, y, x);
  width = getmaxx(win);
  height = getmaxy(win);

  for (row = 0, pBuffer = field->buf;
       row < height;
       row++, pBuffer += width)
    {
      if ((len = (int)(After_End_Of_Data(pBuffer, width) - pBuffer)) > 0)
	{
	  wmove(win, row, 0);
	  myADDNSTR(win, pBuffer, len);
	}
    }
  wmove(win, y, x);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static void Window_To_Buffer(
|                                          WINDOW * win,
|                                          FIELD  * field)
|
|   Description   :  Copy the content of the window into the buffer.
|                    The multiple lines of a window are simply
|                    concatenated into the buffer. Pad characters in
|                    the window will be replaced by blanks in the buffer.
|
|   Return Values :  -
+--------------------------------------------------------------------------*/
static void
Window_To_Buffer(WINDOW *win, FIELD *field)
{
  int pad;
  int len = 0;
  FIELD_CELL *p;
  int row, height;

  assert(win && field && field->buf);

  pad = field->pad;
  p = field->buf;
  height = getmaxy(win);

  for (row = 0; (row < height) && (row < field->drows); row++)
    {
      wmove(win, row, 0);
      len += myINNSTR(win, p + len, field->dcols);
    }
  p[len] = myZEROS;

  /* replace visual padding character by blanks in buffer */
  if (pad != C_BLANK)
    {
      int i;

      for (i = 0; i < len; i++, p++)
	{
	  if ((unsigned long)CharOf(*p) == ChCharOf(pad)
#if USE_WIDEC_SUPPORT
	      && p->chars[1] == 0
#endif
	      && AttrOf(*p) == ChAttrOf(pad))
	    *p = myBLANK;
	}
    }
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static void Synchronize_Buffer(FORM * form)
|
|   Description   :  If there was a change, copy the content of the
|                    window into the buffer, so the buffer is synchronized
|                    with the windows content. We have to indicate that the
|                    buffer needs validation due to the change.
|
|   Return Values :  -
+--------------------------------------------------------------------------*/
INLINE static void
Synchronize_Buffer(FORM *form)
{
  if (form->status & _WINDOW_MODIFIED)
    {
      form->status &= ~_WINDOW_MODIFIED;
      form->status |= _FCHECK_REQUIRED;
      Window_To_Buffer(form->w, form->current);
      wmove(form->w, form->currow, form->curcol);
    }
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static bool Field_Grown( FIELD *field, int amount)
|
|   Description   :  This function is called for growable dynamic fields
|                    only. It has to increase the buffers and to allocate
|                    a new window for this field.
|                    This function has the side effect to set a new
|                    field-buffer pointer, the dcols and drows values
|                    as well as a new current Window for the field.
|
|   Return Values :  TRUE     - field successfully increased
|                    FALSE    - there was some error
+--------------------------------------------------------------------------*/
static bool
Field_Grown(FIELD *field, int amount)
{
  bool result = FALSE;

  if (field && Growable(field))
    {
      bool single_line_field = Single_Line_Field(field);
      int old_buflen = Buffer_Length(field);
      int new_buflen;
      int old_dcols = field->dcols;
      int old_drows = field->drows;
      FIELD_CELL *oldbuf = field->buf;
      FIELD_CELL *newbuf;

      int growth;
      FORM *form = field->form;
      bool need_visual_update = ((form != (FORM *)0) &&
				 (form->status & _POSTED) &&
				 (form->current == field));

      if (need_visual_update)
	Synchronize_Buffer(form);

      if (single_line_field)
	{
	  growth = field->cols * amount;
	  if (field->maxgrow)
	    growth = Minimum(field->maxgrow - field->dcols, growth);
	  field->dcols += growth;
	  if (field->dcols == field->maxgrow)
	    field->status &= ~_MAY_GROW;
	}
      else
	{
	  growth = (field->rows + field->nrow) * amount;
	  if (field->maxgrow)
	    growth = Minimum(field->maxgrow - field->drows, growth);
	  field->drows += growth;
	  if (field->drows == field->maxgrow)
	    field->status &= ~_MAY_GROW;
	}
      /* drows, dcols changed, so we get really the new buffer length */
      new_buflen = Buffer_Length(field);
      newbuf = (FIELD_CELL *)malloc(Total_Buffer_Size(field));
      if (!newbuf)
	{
	  /* restore to previous state */
	  field->dcols = old_dcols;
	  field->drows = old_drows;
	  if ((single_line_field && (field->dcols != field->maxgrow)) ||
	      (!single_line_field && (field->drows != field->maxgrow)))
	    field->status |= _MAY_GROW;
	}
      else
	{
	  /* Copy all the buffers.  This is the reason why we can't just use
	   * realloc().
	   */
	  int i, j;
	  FIELD_CELL *old_bp;
	  FIELD_CELL *new_bp;

	  result = TRUE;	/* allow sharing of recovery on failure */

	  field->buf = newbuf;
	  for (i = 0; i <= field->nbuf; i++)
	    {
	      new_bp = Address_Of_Nth_Buffer(field, i);
	      old_bp = oldbuf + i * (1 + old_buflen);
	      for (j = 0; j < old_buflen; ++j)
		new_bp[j] = old_bp[j];
	      while (j < new_buflen)
		new_bp[j++] = myBLANK;
	      new_bp[new_buflen] = myZEROS;
	    }

#if USE_WIDEC_SUPPORT
	  if (wresize(field->working, 1, Buffer_Length(field) + 1) == ERR)
	    result = FALSE;
#endif

	  if (need_visual_update && result)
	    {
	      WINDOW *new_window = newpad(field->drows, field->dcols);

	      if (new_window != 0)
		{
		  assert(form != (FORM *)0);
		  if (form->w)
		    delwin(form->w);
		  form->w = new_window;
		  Set_Field_Window_Attributes(field, form->w);
		  werase(form->w);
		  Buffer_To_Window(field, form->w);
		  untouchwin(form->w);
		  wmove(form->w, form->currow, form->curcol);
		}
	      else
		result = FALSE;
	    }

	  if (result)
	    {
	      free(oldbuf);
	      /* reflect changes in linked fields */
	      if (field != field->link)
		{
		  FIELD *linked_field;

		  for (linked_field = field->link;
		       linked_field != field;
		       linked_field = linked_field->link)
		    {
		      linked_field->buf = field->buf;
		      linked_field->drows = field->drows;
		      linked_field->dcols = field->dcols;
		    }
		}
	    }
	  else
	    {
	      /* restore old state */
	      field->dcols = old_dcols;
	      field->drows = old_drows;
	      field->buf = oldbuf;
	      if ((single_line_field &&
		   (field->dcols != field->maxgrow)) ||
		  (!single_line_field &&
		   (field->drows != field->maxgrow)))
		field->status |= _MAY_GROW;
	      free(newbuf);
	    }
	}
    }
  return (result);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  int _nc_Position_Form_Cursor(FORM * form)
|
|   Description   :  Position the cursor in the window for the current
|                    field to be in sync. with the currow and curcol
|                    values.
|
|   Return Values :  E_OK              - success
|                    E_BAD_ARGUMENT    - invalid form pointer
|                    E_SYSTEM_ERROR    - form has no current field or
|                                        field-window
+--------------------------------------------------------------------------*/
NCURSES_EXPORT(int)
_nc_Position_Form_Cursor(FORM *form)
{
  FIELD *field;
  WINDOW *formwin;

  if (!form)
    return (E_BAD_ARGUMENT);

  if (!form->w || !form->current)
    return (E_SYSTEM_ERROR);

  field = form->current;
  formwin = Get_Form_Window(form);

  wmove(form->w, form->currow, form->curcol);
  if (Has_Invisible_Parts(field))
    {
      /* in this case fieldwin isn't derived from formwin, so we have
         to move the cursor in formwin by hand... */
      wmove(formwin,
	    field->frow + form->currow - form->toprow,
	    field->fcol + form->curcol - form->begincol);
      wcursyncup(formwin);
    }
  else
    wcursyncup(form->w);
  return (E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  int _nc_Refresh_Current_Field(FORM * form)
|
|   Description   :  Propagate the changes in the fields window to the
|                    window of the form.
|
|   Return Values :  E_OK              - on success
|                    E_BAD_ARGUMENT    - invalid form pointer
|                    E_SYSTEM_ERROR    - general error
+--------------------------------------------------------------------------*/
NCURSES_EXPORT(int)
_nc_Refresh_Current_Field(FORM *form)
{
  WINDOW *formwin;
  FIELD *field;

  T((T_CALLED("_nc_Refresh_Current_Field(%p)"), form));

  if (!form)
    RETURN(E_BAD_ARGUMENT);

  if (!form->w || !form->current)
    RETURN(E_SYSTEM_ERROR);

  field = form->current;
  formwin = Get_Form_Window(form);

  if (field->opts & O_PUBLIC)
    {
      if (Is_Scroll_Field(field))
	{
	  /* Again, in this case the fieldwin isn't derived from formwin,
	     so we have to perform a copy operation. */
	  if (Single_Line_Field(field))
	    {
	      /* horizontal scrolling */
	      if (form->curcol < form->begincol)
		form->begincol = form->curcol;
	      else
		{
		  if (form->curcol >= (form->begincol + field->cols))
		    form->begincol = form->curcol - field->cols + 1;
		}
	      copywin(form->w,
		      formwin,
		      0,
		      form->begincol,
		      field->frow,
		      field->fcol,
		      field->frow,
		      field->cols + field->fcol - 1,
		      0);
	    }
	  else
	    {
	      /* A multi-line, i.e. vertical scrolling field */
	      int row_after_bottom, first_modified_row, first_unmodified_row;

	      if (field->drows > field->rows)
		{
		  row_after_bottom = form->toprow + field->rows;
		  if (form->currow < form->toprow)
		    {
		      form->toprow = form->currow;