source: bootcd/isolinux/syslinux-6.03/gpxe/src/hci/mucurses/clear.c

#include <curses.h>
#include "mucurses.h"
#include "cursor.h"

/** @file
 *
 * MuCurses clearing functions
 *
 */

FILE_LICENCE ( GPL2_OR_LATER );

/**
 * Clear a window to the bottom from current cursor position
 *
 * @v *win      subject window
 * @ret rc      return status code
 */
int wclrtobot ( WINDOW *win ) {
        struct cursor_pos pos;

        _store_curs_pos( win, &pos );
        do {
                _wputc( win, ' ', WRAP );
        } while ( win->curs_y + win->curs_x );
        _restore_curs_pos( win, &pos );

        return OK;
}

/**
 * Clear a window to the end of the current line
 *
 * @v *win      subject window
 * @ret rc      return status code
 */
int wclrtoeol ( WINDOW *win ) {
        struct cursor_pos pos;

        _store_curs_pos( win, &pos );
        while ( ( win->curs_y - pos.y ) == 0 ) {
                _wputc( win, ' ', WRAP );
        }
        _restore_curs_pos( win, &pos );

        return OK;
}

/**
 * Delete character under the cursor in a window
 *
 * @v *win      subject window
 * @ret rc      return status code
 */
int wdelch ( WINDOW *win ) {
        _wputc( win, ' ', NOWRAP );
        _wcursback( win );

        return OK;
}

/**
 * Delete line under a window's cursor
 *
 * @v *win      subject window
 * @ret rc      return status code
 */
int wdeleteln ( WINDOW *win ) {
        struct cursor_pos pos;

        _store_curs_pos( win, &pos );
        /* let's just set the cursor to the beginning of the line and
           let wclrtoeol do the work :) */
        wmove( win, win->curs_y, 0 );
        wclrtoeol( win );
        _restore_curs_pos( win, &pos );
        return OK;
}

/**
 * Completely clear a window
 *
 * @v *win      subject window
 * @ret rc      return status code
 */
int werase ( WINDOW *win ) {
        wmove( win, 0, 0 );
        wclrtobot( win );
        return OK;
}