usr/src/lib/libcurses/addch.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)addch.c     5.1 (Berkeley) %G%";
#endif not lint

# include       "curses.ext"

/*
 *      This routine adds the character to the current position
 *
 */
waddch(win, c)
reg WINDOW      *win;
char            c;
{
        reg int         x, y;
        reg WINDOW      *wp;
        reg int         newx;

        x = win->_curx;
        y = win->_cury;
# ifdef FULLDEBUG
        fprintf(outf, "ADDCH('%c') at (%d, %d)\n", c, y, x);
# endif
        switch (c) {
          case '\t':
                for (newx = x + (8 - (x & 07)); x < newx; x++)
                        if (waddch(win, ' ') == ERR)
                                return ERR;
                return OK;

          default:
# ifdef FULLDEBUG
                fprintf(outf, "ADDCH: 1: y = %d, x = %d, firstch = %d, lastch = %d\n", y, x, win->_firstch[y], win->_lastch[y]);
# endif
                if (win->_flags & _STANDOUT)
                        c |= _STANDOUT;
                set_ch(win, y, x, c);
                win->_y[y][x++] = c;
                if (x >= win->_maxx) {
                        x = 0;
newline:
                        if (++y >= win->_maxy)
                                if (win->_scroll) {
                                        scroll(win);
                                        --y;
                                }
                                else
                                        return ERR;
                }
# ifdef FULLDEBUG
                fprintf(outf, "ADDCH: 2: y = %d, x = %d, firstch = %d, lastch = %d\n", y, x, win->_firstch[y], win->_lastch[y]);
# endif
                break;
          case '\n':
                wclrtoeol(win);
                if (!NONL)
                        x = 0;
                goto newline;
          case '\r':
                x = 0;
                break;
          case '\b':
                if (--x < 0)
                        x = 0;
                break;
        }
        win->_curx = x;
        win->_cury = y;
        return OK;
}

/*
 * set_ch:
 *      Set the first and last change flags for this window.
 */
static
set_ch(win, y, x, ch)
reg WINDOW      *win;
int             y, x;
{
# ifdef FULLDEBUG
        fprintf(outf, "SET_CH(%0.2o, %d, %d)\n", win, y, x);
# endif
        if (win->_y[y][x] != ch) {
                x += win->_ch_off;
                if (win->_firstch[y] == _NOCHANGE)
                        win->_firstch[y] = win->_lastch[y] = x;
                else if (x < win->_firstch[y])
                        win->_firstch[y] = x;
                else if (x > win->_lastch[y])
                        win->_lastch[y] = x;
# ifdef FULLDEBUG
                fprintf(outf, "SET_CH: change gives f/l: %d/%d [%d/%d]\n",
                        win->_firstch[y], win->_lastch[y],
                        win->_firstch[y] - win->_ch_off,
                        win->_lastch[y] - win->_ch_off);
# endif
        }
}