|                                           FIELDTYPE * typ,|                                           int ch,|                                           TypeArgument *argp)|   |   Description   :  Perform a single character check for character ch|                    according to the fieldtype instance.  ||   Return Values :  TRUE             - Character is valid|                    FALSE            - Character is invalid+--------------------------------------------------------------------------*/static bool Check_Char(FIELDTYPE * typ, int ch, TypeArgument *argp){  if (typ)     {      if (typ->status & _LINKED_TYPE)	{	  assert(argp);	  return(	    Check_Char(typ->left ,ch,argp->left ) ||	    Check_Char(typ->right,ch,argp->right) );	}       else 	{	  if (typ->ccheck)	    return typ->ccheck(ch,(void *)argp);	}    }  return (isprint((unsigned char)ch) ? TRUE : FALSE);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int Display_Or_Erase_Field(|                                           FIELD * field,|                                           bool bEraseFlag)|   |   Description   :  Create a subwindow for the field and display the|                    buffer contents (apply justification if required)|                    or simply erase the field.||   Return Values :  E_OK           - on success|                    E_SYSTEM_ERROR - some error (typical no memory)+--------------------------------------------------------------------------*/static int Display_Or_Erase_Field(FIELD * field, bool bEraseFlag){  WINDOW *win;  WINDOW *fwin;  if (!field)    return E_SYSTEM_ERROR;  fwin = Get_Form_Window(field->form);  win  = derwin(fwin,		field->rows,field->cols,field->frow,field->fcol);  if (!win)     return E_SYSTEM_ERROR;  else    {      if (field->opts & O_VISIBLE)	Set_Field_Window_Attributes(field,win);      else	wattrset(win,getattrs(fwin));      werase(win);    }  if (!bEraseFlag)    {      if (field->opts & O_PUBLIC)	{	  if (Justification_Allowed(field))	    Perform_Justification(field,win);	  else	    Buffer_To_Window(field,win);	}      field->status &= ~_NEWTOP;    }  wsyncup(win);  delwin(win);  return E_OK;}/* Macros to preset the bEraseFlag */#define Display_Field(field) Display_Or_Erase_Field(field,FALSE)#define Erase_Field(field)   Display_Or_Erase_Field(field,TRUE)/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int Synchronize_Field(FIELD * field)|   |   Description   :  Synchronize the windows content with the value in|                    the buffer.||   Return Values :  E_OK                - success|                    E_BAD_ARGUMENT      - invalid field pointer |                    E_SYSTEM_ERROR      - some severe basic error+--------------------------------------------------------------------------*/static int Synchronize_Field(FIELD * field){  FORM *form;  int res = E_OK;  if (!field)    return(E_BAD_ARGUMENT);  if (((form=field->form) != (FORM *)0)      && Field_Really_Appears(field))    {      if (field == form->current)	{ 	  form->currow  = form->curcol = form->toprow = form->begincol = 0;	  werase(form->w);      	  if ( (field->opts & O_PUBLIC) && Justification_Allowed(field) )	    Undo_Justification( field, form->w );	  else	    Buffer_To_Window( field, form->w );	  	  field->status |= _NEWTOP;	  res = _nc_Refresh_Current_Field( form );	}      else	res = Display_Field( field );    }  field->status |= _CHANGED;  return(res);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  static int Synchronize_Linked_Fields(FIELD * field)|   |   Description   :  Propagate the Synchronize_Field function to all linked|                    fields. The first error that occurs in the sequence|                    of updates is the return value.||   Return Values :  E_OK                - success|                    E_BAD_ARGUMENT      - invalid field pointer |                    E_SYSTEM_ERROR      - some severe basic error+--------------------------------------------------------------------------*/static int Synchronize_Linked_Fields(FIELD * field){  FIELD *linked_field;  int res = E_OK;  int syncres;  if (!field)    return(E_BAD_ARGUMENT);  if (!field->link)    return(E_SYSTEM_ERROR);  for(linked_field = field->link;       linked_field!= field;      linked_field = linked_field->link )    {      if (((syncres=Synchronize_Field(linked_field)) != E_OK) &&	  (res==E_OK))	res = syncres;    }  return(res);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  int _nc_Synchronize_Attributes(FIELD * field)|   |   Description   :  If a fields visual attributes have changed, this|                    routine is called to propagate those changes to the|                    screen.  ||   Return Values :  E_OK             - success|                    E_BAD_ARGUMENT   - invalid field pointer|                    E_SYSTEM_ERROR   - some severe basic error+--------------------------------------------------------------------------*/NCURSES_EXPORT(int)_nc_Synchronize_Attributes (FIELD * field){  FORM *form;  int res = E_OK;  WINDOW *formwin;  if (!field)    return(E_BAD_ARGUMENT);  if (((form=field->form) != (FORM *)0)      && Field_Really_Appears(field))    {          if (form->current==field)	{	  Synchronize_Buffer(form);	  Set_Field_Window_Attributes(field,form->w);	  werase(form->w);	  if (field->opts & O_PUBLIC)	    {	      if (Justification_Allowed(field))		Undo_Justification(field,form->w);	      else 		Buffer_To_Window(field,form->w);	    }	  else 	    {	      formwin = Get_Form_Window(form); 	      copywin(form->w,formwin,		      0,0,		      field->frow,field->fcol,		      field->rows-1,field->cols-1,0);	      wsyncup(formwin);	      Buffer_To_Window(field,form->w);	      field->status |= _NEWTOP; /* fake refresh to paint all */	      _nc_Refresh_Current_Field(form);	    }	}      else 	{	  res = Display_Field(field);	}    }  return(res);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  int _nc_Synchronize_Options(FIELD * field,|                                                Field_Options newopts)|   |   Description   :  If a fields options have changed, this routine is|                    called to propagate these changes to the screen and|                    to really change the behavior of the field.||   Return Values :  E_OK                - success|                    E_BAD_ARGUMENT      - invalid field pointer |                    E_SYSTEM_ERROR      - some severe basic error+--------------------------------------------------------------------------*/NCURSES_EXPORT(int)_nc_Synchronize_Options(FIELD *field, Field_Options newopts){  Field_Options oldopts;  Field_Options changed_opts;  FORM *form;  int res = E_OK;  if (!field)    return(E_BAD_ARGUMENT);  oldopts      = field->opts;  changed_opts = oldopts ^ newopts;  field->opts  = newopts;  form         = field->form;  if (form)    {      if (form->current == field)	{	  field->opts = oldopts;	  return(E_CURRENT);	}      if (form->status & _POSTED)	{	  if ((form->curpage == field->page))	    {	      if (changed_opts & O_VISIBLE)		{		  if (newopts & O_VISIBLE)		    res = Display_Field(field);		  else		    res = Erase_Field(field);		}	      else		{		  if ((changed_opts & O_PUBLIC) &&		      (newopts & O_VISIBLE))		    res = Display_Field(field);		}	    }	}    }  if (changed_opts & O_STATIC)    {      bool single_line_field = Single_Line_Field(field);      int res2 = E_OK;      if (newopts & O_STATIC)	{ /* the field becomes now static */	  field->status &= ~_MAY_GROW;	  /* if actually we have no hidden columns, justification may	     occur again */	  if (single_line_field                 &&	      (field->cols == field->dcols)     &&	      (field->just != NO_JUSTIFICATION) &&	      Field_Really_Appears(field))	    {	      res2 = Display_Field(field);	    }	}      else	{ /* field is no longer static */	  if ((field->maxgrow==0) ||	      ( single_line_field && (field->dcols < field->maxgrow)) ||	      (!single_line_field && (field->drows < field->maxgrow)))	    {	      field->status |= _MAY_GROW;	      /* a field with justification now changes its behavior,		 so we must redisplay it */	      if (single_line_field                 &&		  (field->just != NO_JUSTIFICATION) &&		  Field_Really_Appears(field))		{		  res2 = Display_Field(field);		}	 	    }     	}      if (res2 != E_OK)	res = res2;    }  return(res);}/*---------------------------------------------------------------------------|   Facility      :  libnform  |   Function      :  int _nc_Set_Current_Field(FORM  * form,|                                              FIELD * newfield)|   |   Description   :  Make the newfield the new current field.||   Return Values :  E_OK                - success|                    E_BAD_ARGUMENT      - invalid form or field pointer |                    E_SYSTEM_ERROR      - some severe basic error+--------------------------------------------------------------------------*/NCURSES_EXPORT(int)_nc_Set_Current_Field(FORM  *form, FIELD *newfield){  FIELD  *field;  WINDOW *new_window;  if (!form || !newfield || !form->current || (newfield->form!=form))    return(E_BAD_ARGUMENT);  if ( (form->status & _IN_DRIVER) )    return(E_BAD_STATE);  if (!(form->field))    return(E_NOT_CONNECTED);  field = form->current;   if ((field!=newfield) ||       !(form->status & _POSTED))    {      if ((form->w) && 	  (field->opts & O_VISIBLE) &&	  (field->form->curpage == field->page))	{	  _nc_Refresh_Current_Field(form);	  if (field->opts & O_PUBLIC)	    {	      if (field->drows > field->rows)		{		  if (form->toprow==0)		    field->status &= ~_NEWTOP;		  else 		    field->status |= _NEWTOP;		} 	      else 		{		  if (Justification_Allowed(field))		    {		      Window_To_Buffer(form->w,field);		      werase(form->w);		      Perform_Justification(field,form->w);		      wsyncup(form->w);		    }		}	    }	  delwin(form->w);	  form->w = (WINDOW *)0;	}            field = newfield;      if (Has_Invisible_Parts(field))	new_window = newpad(field->drows,field->dcols);      else 	new_window = derwin(Get_Form_Window(form),			    field->rows,field->cols,field->frow,field->fcol);      if (!new_window) 	return(E_SYSTEM_ERROR);