frm_driver.c

ncurses 库 可能有用酒用 没用就算了 我觉得还可以用

  FIELD *field = form->current;
  FIELD_CELL *pos;

  T((T_CALLED("IFN_End_Of_Field(%p)"), form));
  Synchronize_Buffer(form);
  pos = After_End_Of_Data(field->buf, Buffer_Length(field));
  if (pos == (field->buf + Buffer_Length(field)))
    pos--;
  Adjust_Cursor_Position(form, pos);
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_Beginning_Of_Line(FORM * form)
|
|   Description   :  Place the cursor on the first non-pad character in
|                    the current line of the field.
|
|   Return Values :  E_OK         - success
+--------------------------------------------------------------------------*/
static int
IFN_Beginning_Of_Line(FORM *form)
{
  FIELD *field = form->current;

  T((T_CALLED("IFN_Beginning_Of_Line(%p)"), form));
  Synchronize_Buffer(form);
  Adjust_Cursor_Position(form,
			 Get_Start_Of_Data(Address_Of_Current_Row_In_Buffer(form),
					   field->dcols));
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_End_Of_Line(FORM * form)
|
|   Description   :  Place the cursor after the last non-pad character in the
|                    current line of the field. If the field occupies the
|                    last column in the line, the cursor is positioned on the
|                    last character of the line.
|
|   Return Values :  E_OK        - success
+--------------------------------------------------------------------------*/
static int
IFN_End_Of_Line(FORM *form)
{
  FIELD *field = form->current;
  FIELD_CELL *pos;
  FIELD_CELL *bp;

  T((T_CALLED("IFN_End_Of_Line(%p)"), form));
  Synchronize_Buffer(form);
  bp = Address_Of_Current_Row_In_Buffer(form);
  pos = After_End_Of_Data(bp, field->dcols);
  if (pos == (bp + field->dcols))
    pos--;
  Adjust_Cursor_Position(form, pos);
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_Left_Character(FORM * form)
|
|   Description   :  Move one character to the left in the current line.
|                    This doesn't cycle.
|
|   Return Values :  E_OK             - success
|                    E_REQUEST_DENIED - already in first column
+--------------------------------------------------------------------------*/
static int
IFN_Left_Character(FORM *form)
{
  int amount = myWCWIDTH(form->w, form->currow, form->curcol - 1);
  int oldcol = form->curcol;

  T((T_CALLED("IFN_Left_Character(%p)"), form));
  if ((form->curcol -= amount) < 0)
    {
      form->curcol = oldcol;
      returnCode(E_REQUEST_DENIED);
    }
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_Right_Character(FORM * form)
|
|   Description   :  Move one character to the right in the current line.
|                    This doesn't cycle.
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - already in last column
+--------------------------------------------------------------------------*/
static int
IFN_Right_Character(FORM *form)
{
  int amount = myWCWIDTH(form->w, form->currow, form->curcol);
  int oldcol = form->curcol;

  T((T_CALLED("IFN_Right_Character(%p)"), form));
  if ((form->curcol += amount) >= form->current->dcols)
    {
#if GROW_IF_NAVIGATE
      FIELD *field = form->current;

      if (Single_Line_Field(field) && Field_Grown(field, 1))
	returnCode(E_OK);
#endif
      form->curcol = oldcol;
      returnCode(E_REQUEST_DENIED);
    }
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_Up_Character(FORM * form)
|
|   Description   :  Move one line up. This doesn't cycle through the lines
|                    of the field.
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - already in last column
+--------------------------------------------------------------------------*/
static int
IFN_Up_Character(FORM *form)
{
  T((T_CALLED("IFN_Up_Character(%p)"), form));
  if ((--(form->currow)) < 0)
    {
      form->currow++;
      returnCode(E_REQUEST_DENIED);
    }
  returnCode(E_OK);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int IFN_Down_Character(FORM * form)
|
|   Description   :  Move one line down. This doesn't cycle through the
|                    lines of the field.
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - already in last column
+--------------------------------------------------------------------------*/
static int
IFN_Down_Character(FORM *form)
{
  FIELD *field = form->current;

  T((T_CALLED("IFN_Down_Character(%p)"), form));
  if ((++(form->currow)) == field->drows)
    {
#if GROW_IF_NAVIGATE
      if (!Single_Line_Field(field) && Field_Grown(field, 1))
	returnCode(E_OK);
#endif
      --(form->currow);
      returnCode(E_REQUEST_DENIED);
    }
  returnCode(E_OK);
}
/*----------------------------------------------------------------------------
  END of Intra-Field Navigation routines
  --------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
  Vertical scrolling helper routines
  --------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Generic(FORM *form, int nlines)
|
|   Description   :  Scroll multi-line field forward (nlines>0) or
|                    backward (nlines<0) this many lines.
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - can't scroll
+--------------------------------------------------------------------------*/
static int
VSC_Generic(FORM *form, int nlines)
{
  FIELD *field = form->current;
  int res = E_REQUEST_DENIED;
  int rows_to_go = (nlines > 0 ? nlines : -nlines);

  if (nlines > 0)
    {
      if ((rows_to_go + form->toprow) > (field->drows - field->rows))
	rows_to_go = (field->drows - field->rows - form->toprow);

      if (rows_to_go > 0)
	{
	  form->currow += rows_to_go;
	  form->toprow += rows_to_go;
	  res = E_OK;
	}
    }
  else
    {
      if (rows_to_go > form->toprow)
	rows_to_go = form->toprow;

      if (rows_to_go > 0)
	{
	  form->currow -= rows_to_go;
	  form->toprow -= rows_to_go;
	  res = E_OK;
	}
    }
  return (res);
}
/*----------------------------------------------------------------------------
  End of Vertical scrolling helper routines
  --------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
  Vertical scrolling routines
  --------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int Vertical_Scrolling(
|                                           int (* const fct) (FORM *),
|                                           FORM * form)
|
|   Description   :  Performs the generic vertical scrolling routines.
|                    This has to check for a multi-line field and to set
|                    the _NEWTOP flag if scrolling really occurred.
|
|   Return Values :  Propagated error code from low-level driver calls
+--------------------------------------------------------------------------*/
static int
Vertical_Scrolling(int (*const fct) (FORM *), FORM *form)
{
  int res = E_REQUEST_DENIED;

  if (!Single_Line_Field(form->current))
    {
      res = fct(form);
      if (res == E_OK)
	form->current->status |= _NEWTOP;
    }
  return (res);
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Line_Forward(FORM * form)
|
|   Description   :  Scroll multi-line field forward a line
|
|   Return Values :  E_OK                - success
|                    E_REQUEST_DENIED    - no data ahead
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Line_Forward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Line_Forward(%p)"), form));
  returnCode(VSC_Generic(form, 1));
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Line_Backward(FORM * form)
|
|   Description   :  Scroll multi-line field backward a line
|
|   Return Values :  E_OK                - success
|                    E_REQUEST_DENIED    - no data behind
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Line_Backward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Line_Backward(%p)"), form));
  returnCode(VSC_Generic(form, -1));
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Page_Forward(FORM * form)
|
|   Description   :  Scroll a multi-line field forward a page
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - no data ahead
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Page_Forward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Page_Forward(%p)"), form));
  returnCode(VSC_Generic(form, form->current->rows));
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Half_Page_Forward(FORM * form)
|
|   Description   :  Scroll a multi-line field forward half a page
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - no data ahead
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Half_Page_Forward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Half_Page_Forward(%p)"), form));
  returnCode(VSC_Generic(form, (form->current->rows + 1) / 2));
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Page_Backward(FORM * form)
|
|   Description   :  Scroll a multi-line field backward a page
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - no data behind
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Page_Backward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Page_Backward(%p)"), form));
  returnCode(VSC_Generic(form, -(form->current->rows)));
}

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int VSC_Scroll_Half_Page_Backward(FORM * form)
|
|   Description   :  Scroll a multi-line field backward half a page
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - no data behind
+--------------------------------------------------------------------------*/
static int
VSC_Scroll_Half_Page_Backward(FORM *form)
{
  T((T_CALLED("VSC_Scroll_Half_Page_Backward(%p)"), form));
  returnCode(VSC_Generic(form, -((form->current->rows + 1) / 2)));
}
/*----------------------------------------------------------------------------
  End of Vertical scrolling routines
  --------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
  Horizontal scrolling helper routines
  --------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int HSC_Generic(FORM *form, int ncolumns)
|
|   Description   :  Scroll single-line field forward (ncolumns>0) or
|                    backward (ncolumns<0) this many columns.
|
|   Return Values :  E_OK              - success
|                    E_REQUEST_DENIED  - can't scroll
+--------------------------------------------------------------------------*/
static int
HSC_Generic(FORM *form, int ncolumns)
{
  FIELD *field = form->current;
  int res = E_REQUEST_DENIED;
  int cols_to_go = (ncolumns > 0 ? ncolumns : -ncolumns);

  if (ncolumns > 0)
    {
      if ((cols_to_go + form->begincol) > (field->dcols - field->cols))
	cols_to_go = field->dcols - field->cols - form->begincol;

      if (cols_to_go > 0)
	{
	  form->curcol += cols_to_go;
	  form->begincol += cols_to_go;
	  res = E_OK;
	}
    }
  else
    {
      if (cols_to_go > form->begincol)
	cols_to_go = form->begincol;

      if (cols_to_go > 0)
	{
	  form->curcol -= cols_to_go;
	  form->begincol -= cols_to_go;
	  res = E_OK;
	}
    }
  return (res);
}
/*----------------------------------------------------------------------------
  End of Horizontal scrolling helper routines
  --------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
  Horizontal scrolling routines
  --------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------
|   Facility      :  libnform
|   Function      :  static int Horizontal_Scrolling(
|                                          int (* const fct) (FORM *),
|                                          FORM * form)
|
|   Description   :  Performs the generic horizontal scrolling routines.
|                    This has to check for a single-line field.
|
|   Return Values :  Propagated error code from low