date and time created 83/08/09 18:37:52 by edward

[unix-history] / usr / src / usr.bin / window / wwclreol.c

#ifndef lint
static  char *sccsid = "@(#)wwclreol.c  3.1 83/08/09";
#endif

#include "ww.h"

/*
* Clear w to the end of line.
* If cleared is true, then the screen line has already been cleared
* previously.
*/
wwclreol(w, line, col, cleared)
register struct ww *w;
int line;
{
       register i;
       int row = line - w->ww_scroll;
       int srow = w->ww_w.t + row;
       int scol = w->ww_w.l + col;
       register union ww_char *s, *buf;
       register char *smap, *win;
       int nblank, ncleared;

       if (row < 0 || row >= w->ww_w.nr) {
               /* can't even see it, so just clear the buffer */
               buf = &w->ww_buf[line][col]; 
               for (i = w->ww_w.nc - col; --i >= 0;)
                       buf++->c_w = ' ';
               return;
       }
       smap = &wwsmap[srow][scol];
       s = &wwns[srow][scol];
       win = &w->ww_win[row][col];
       buf = &w->ww_buf[row][col];
       ncleared = nblank = 0;
       for (i = w->ww_w.nc - col; --i >= 0;) {
               if (*smap++ != w->ww_index) {
                       if (s++->c_w == ' ')
                               nblank++;
                       buf++;
                       win++;
                       continue;
               }
               ncleared++; 
               buf++->c_w = ' ';
               if (*win == 0) {
                       nblank++;
                       s++->c_w = ' ';
                       win++;
               } else
                       s++->c_w = ' ' | *win++ << WWC_MSHIFT;
       }
       if (!cleared && tt.tt_clreol != 0
           && ncleared > wwncol - scol - nblank
           && nblank > (wwncol - scol) / 2) {
               /* clear to the end */
               (*tt.tt_move)(srow, scol);
               (*tt.tt_clreol)();
               s = &wwos[srow][scol];
               for (i = w->ww_w.nc - col; --i >= 0;)
                       s++->c_w = ' ';
       }
}