|                    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;  if ( (++(form->currow)) == field->drows )    {#if GROW_IF_NAVIGATE      if (!Single_Line_Field(field) && Field_Grown(field,1))	return(E_OK);#endif      --(form->currow);      return(E_REQUEST_DENIED);    }  return(E_OK);}/*----------------------------------------------------------------------------  END of Intra-Field Navigation routines   --------------------------------------------------------------------------*//*----------------------------------------------------------------------------  Vertical scrolling helper routines  --------------------------------------------------------------------------*//*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int VSC_Generic(FORM *form, int lines)||   Description   :  Scroll multi-line field forward (lines>0) or|                    backward (lines<0) this many lines.||   Return Values :  E_OK              - success |                    E_REQUEST_DENIED  - can't scroll+--------------------------------------------------------------------------*/static int VSC_Generic(FORM *form, int lines){  FIELD *field = form->current;  int res = E_REQUEST_DENIED;  int rows_to_go = (lines > 0 ? lines : -lines);  if (lines > 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){  return 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){  return 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){  return 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){  return 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){  return 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){  return 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 columns)||   Description   :  Scroll single-line field forward (columns>0) or|                    backward (columns<0) this many columns.||   Return Values :  E_OK              - success |                    E_REQUEST_DENIED  - can't scroll+--------------------------------------------------------------------------*/static int HSC_Generic(FORM *form, int columns){  FIELD *field = form->current;  int res = E_REQUEST_DENIED;  int cols_to_go = (columns > 0 ? columns : -columns);  if (columns > 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-level driver calls+--------------------------------------------------------------------------*/static int Horizontal_Scrolling(int (* const fct) (FORM *), FORM * form){  if (Single_Line_Field(form->current))    return fct(form);  else    return(E_REQUEST_DENIED);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Scroll_Char_Forward(FORM * form)|   |   Description   :  Scroll single-line field forward a character||   Return Values :  E_OK                - success|                    E_REQUEST_DENIED    - no data ahead+--------------------------------------------------------------------------*/static int HSC_Scroll_Char_Forward(FORM *form){  return HSC_Generic(form,1);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Scroll_Char_Backward(FORM * form)|   |   Description   :  Scroll single-line field backward a character||   Return Values :  E_OK                - success|                    E_REQUEST_DENIED    - no data behind+--------------------------------------------------------------------------*/static int HSC_Scroll_Char_Backward(FORM *form){  return HSC_Generic(form,-1);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Horizontal_Line_Forward(FORM* form)|   |   Description   :  Scroll single-line field forward a line||   Return Values :  E_OK                - success|                    E_REQUEST_DENIED    - no data ahead+--------------------------------------------------------------------------*/static int HSC_Horizontal_Line_Forward(FORM * form){  return HSC_Generic(form,form->current->cols);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Horizontal_Half_Line_Forward(FORM* form)|   |   Description   :  Scroll single-line field forward half a line||   Return Values :  E_OK               - success|                    E_REQUEST_DENIED   - no data ahead+--------------------------------------------------------------------------*/static int HSC_Horizontal_Half_Line_Forward(FORM * form){  return HSC_Generic(form,(form->current->cols + 1)/2);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Horizontal_Line_Backward(FORM* form)|   |   Description   :  Scroll single-line field backward a line||   Return Values :  E_OK                - success|                    E_REQUEST_DENIED    - no data behind+--------------------------------------------------------------------------*/static int HSC_Horizontal_Line_Backward(FORM * form){  return HSC_Generic(form,-(form->current->cols));}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int HSC_Horizontal_Half_Line_Backward(FORM* form)|   |   Description   :  Scroll single-line field backward half a line||   Return Values :  E_OK                - success|                    E_REQUEST_DENIED    - no data behind+--------------------------------------------------------------------------*/static int HSC_Horizontal_Half_Line_Backward(FORM * form){  return HSC_Generic(form,-((form->current->cols + 1)/2));}/*----------------------------------------------------------------------------  End of Horizontal scrolling routines  --------------------------------------------------------------------------*//*----------------------------------------------------------------------------  Helper routines for Field Editing  --------------------------------------------------------------------------*//*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static bool Is_There_Room_For_A_Line(FORM * form)|   |   Description   :  Check whether or not there is enough room in the|                    buffer to enter a whole line.||   Return Values :  TRUE   - there is enough space|                    FALSE  - there is not enough space+--------------------------------------------------------------------------*/INLINE static bool Is_There_Room_For_A_Line(FORM * form){  FIELD *field = form->current;  char *begin_of_last_line, *s;    Synchronize_Buffer(form);  begin_of_last_line = Address_Of_Row_In_Buffer(field,(field->drows-1));  s  = After_End_Of_Data(begin_of_last_line,field->dcols);  return ((s==begin_of_last_line) ? TRUE : FALSE);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static bool Is_There_Room_For_A_Char_In_Line(FORM * form)|   |   Description   :  Checks whether or not there is room for a new character|                    in the current line.||   Return Values :  TRUE    - there is room|                    FALSE   - there is not enough room (line full)+--------------------------------------------------------------------------*/INLINE static bool Is_There_Room_For_A_Char_In_Line(FORM * form){  int last_char_in_