nuttx-apps/graphics/pdcurs34/pdcurses/pdc_clear.c

/****************************************************************************
 * apps/graphics/pdcurses/pdc_clear.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Adapted from the original public domain pdcurses by Gregory Nutt
 ****************************************************************************/

/* Name: clear
 *
 * Synopsis:
 *       int clear(void);
 *       int wclear(WINDOW *win);
 *       int erase(void);
 *       int werase(WINDOW *win);
 *       int clrtobot(void);
 *       int wclrtobot(WINDOW *win);
 *       int clrtoeol(void);
 *       int wclrtoeol(WINDOW *win);
 *
 * Description:
 *       erase() and werase() copy blanks (i.e. the background chtype) to
 *       every cell of the window.
 *
 *       clear() and wclear() are similar to erase() and werase(), but
 *       they also call clearok() to ensure that the the window is
 *       cleared on the next wrefresh().
 *
 *       clrtobot() and wclrtobot() clear the window from the current
 *       cursor position to the end of the window.
 *
 *       clrtoeol() and wclrtoeol() clear the window from the current
 *       cursor position to the end of the current line.
 *
 * Return Value:
 *       All functions return OK on success and ERR on error.
 *
 * Portability                                X/Open    BSD    SYS V
 *       clear                                   Y       Y       Y
 *       wclear                                  Y       Y       Y
 *       erase                                   Y       Y       Y
 *       werase                                  Y       Y       Y
 *       clrtobot                                Y       Y       Y
 *       wclrtobot                               Y       Y       Y
 *       clrtoeol                                Y       Y       Y
 *       wclrtoeol                               Y       Y       Y
 */

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include "curspriv.h"

/****************************************************************************
 * Public Functions
 ****************************************************************************/

int wclrtoeol(WINDOW *win)
{
  chtype blank;
  chtype *ptr;
  int x;
  int y;
  int minx;

  PDC_LOG(("wclrtoeol() - called: Row: %d Col: %d\n", win->_cury, win->_curx));

  if (!win)
    {
      return ERR;
    }

  y = win->_cury;
  x = win->_curx;

  /* wrs (4/10/93) account for window background */

  blank = win->_bkgd;

  for (minx = x, ptr = &win->_y[y][x]; minx < win->_maxx; minx++, ptr++)
    {
      *ptr = blank;
    }

  if (x < win->_firstch[y] || win->_firstch[y] == _NO_CHANGE)
    {
      win->_firstch[y] = x;
    }

  win->_lastch[y] = win->_maxx - 1;

  PDC_sync(win);
  return OK;
}

int clrtoeol(void)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#endif
  PDC_LOG(("clrtoeol() - called\n"));

  return wclrtoeol(stdscr);
}

int wclrtobot(WINDOW *win)
{
  int savey = win->_cury;
  int savex = win->_curx;

  PDC_LOG(("wclrtobot() - called\n"));

  if (!win)
    {
      return ERR;
    }

  /* should this involve scrolling region somehow ? */

  if (win->_cury + 1 < win->_maxy)
    {
      win->_curx = 0;
      win->_cury++;

      for (; win->_maxy > win->_cury; win->_cury++)
        {
          wclrtoeol(win);
        }

      win->_cury = savey;
      win->_curx = savex;
    }

  wclrtoeol(win);

  PDC_sync(win);
  return OK;
}

int clrtobot(void)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#endif
  PDC_LOG(("clrtobot() - called\n"));

  return wclrtobot(stdscr);
}

int werase(WINDOW *win)
{
  PDC_LOG(("werase() - called\n"));

  if (wmove(win, 0, 0) == ERR)
    {
      return ERR;
    }

  return wclrtobot(win);
}

int erase(void)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#endif
  PDC_LOG(("erase() - called\n"));

  return werase(stdscr);
}

int wclear(WINDOW *win)
{
  PDC_LOG(("wclear() - called\n"));

  if (!win)
    {
      return ERR;
    }

  win->_clear = true;
  return werase(win);
}

int clear(void)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#endif
  PDC_LOG(("clear() - called\n"));

  return wclear(stdscr);
}