check tt_retain in scrollling up, instead of down (for hp2621)

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

#ifndef lint
static  char *sccsid = "@(#)wwupdate.c  3.7 83/08/19";
#endif

#include "ww.h"
#include "tt.h"

wwupdate()
{
       int i;
       register j;
       int c, x;
       register union ww_char *ns, *os;
       register char *p, *q;
       char m;
       char *touched;
       register didit;
       char buf[512];                  /* > wwncol */
       union ww_char lastc;

       wwnupdate++;
       for (i = 0, touched = wwtouched; i < wwnrow; i++, touched++) {
               if (!*touched)
                       continue;
               wwntouched++;
               *touched = 0;

               ns = wwns[i];
               os = wwos[i];
               didit = 0;
               for (j = 0; j < wwncol;) {
                       for (; j++ < wwncol && ns++->c_w == os++->c_w;)
                               ;
                       if (j > wwncol)
                               break;
                       p = buf;
                       m = ns[-1].c_m;
                       c = j - 1;
                       os[-1] = ns[-1];
                       *p++ = ns[-1].c_c;
                       x = 5;
                       q = p;
                       while (j < wwncol && ns->c_m == m) {
                               *p++ = ns->c_c;
                               if (ns->c_w == os->c_w) {
                                       if (--x <= 0)
                                               break;
                                       os++;
                                       ns++;
                               } else {
                                       x = 5;
                                       q = p;
                                       lastc = *os;
                                       *os++ = *ns++;
                               }
                               j++;
                       }
                       if (wwwrap
                           && i == wwnrow - 1 && q - buf + c == wwncol) {
                               if (tt.tt_setinsert != 0) {
                                       (*tt.tt_move)(i, c);
                                       (*tt.tt_setmodes)(m);
                                       (*tt.tt_write)(buf + 1, q - 1);
                                       (*tt.tt_move)(i, c);
                                       (*tt.tt_setinsert)(1);
                                       (*tt.tt_write)(buf, buf);
                                       (*tt.tt_setinsert)(0);
                               } else {
                                       os[-1] = lastc;
                                       (*tt.tt_move)(i, c);
                                       (*tt.tt_setmodes)(m);
                                       (*tt.tt_write)(buf, q - 2);
                               }
                       } else {
                               (*tt.tt_move)(i, c);
                               (*tt.tt_setmodes)(m);
                               (*tt.tt_write)(buf, q - 1);
                       }
                       didit++;
               }
               if (!didit)
                       wwnmiss++;
       }
}