Re: avoid uninitialised attr in rasops_scrollback()

[Jonathan Gray]

On Tue, May 01, 2018 at 05:03:26PM +0000, Miod Vallat wrote:
> > scrollback isn't part of wsdisplay_emulops but rather wsdisplay_accessops.
> > It isn't clear how to properly get an attr in wsscrollback()
> > GETCHAR/getchar is part of wsmoused and sc->sc_accessops->getchar
> > may be NULL.
> 
> Ok, ignore that. There is a simpler solution.

Thanks, looks good/ok.  Shouldn't the eraserows call in
rasops_doswitch() also use scr->rs_defattr for the attr argument?

Index: rasops.c
===================================================================
RCS file: /cvs/src/sys/dev/rasops/rasops.c,v
retrieving revision 1.53
diff -u -p -r1.53 rasops.c
--- rasops.c    27 Apr 2018 21:36:12 -0000      1.53
+++ rasops.c    2 May 2018 01:53:38 -0000
@@ -1373,6 +1373,7 @@ struct rasops_screen {
        int rs_visible;
        int rs_crow;
        int rs_ccol;
+       long rs_defattr;
 
        int rs_sbscreens;
 #define RS_SCROLLBACK_SCREENS 5
@@ -1412,10 +1413,11 @@ rasops_alloc_screen(void *v, void **cook
        scr->rs_visible = (ri->ri_nscreens == 0);
        scr->rs_crow = -1;
        scr->rs_ccol = -1;
+       scr->rs_defattr = *attrp;
 
        for (i = 0; i < scr->rs_dispoffset; i++) {
                scr->rs_bs[i].uc = ' ';
-               scr->rs_bs[i].attr = *attrp;
+               scr->rs_bs[i].attr = scr->rs_defattr;
        }
 
        if (ri->ri_bs && scr->rs_visible) {
@@ -1425,7 +1427,8 @@ rasops_alloc_screen(void *v, void **cook
        } else {
                for (i = 0; i < ri->ri_rows * ri->ri_cols; i++) {
                        scr->rs_bs[scr->rs_dispoffset + i].uc = ' ';
-                       scr->rs_bs[scr->rs_dispoffset + i].attr = *attrp;
+                       scr->rs_bs[scr->rs_dispoffset + i].attr =
+                           scr->rs_defattr;
                }
        }
 
@@ -1474,12 +1477,10 @@ rasops_doswitch(void *v)
        struct rasops_info *ri = v;
        struct rasops_screen *scr = ri->ri_switchcookie;
        int row, col;
-       long attr;
 
        rasops_cursor(ri, 0, 0, 0);
        ri->ri_active->rs_visible = 0;
-       ri->ri_alloc_attr(ri, 0, 0, 0, &attr);
-       ri->ri_eraserows(ri, 0, ri->ri_rows, attr);
+       ri->ri_eraserows(ri, 0, ri->ri_rows, scr->rs_defattr);
        ri->ri_active = scr;
        ri->ri_active->rs_visible = 1;
        ri->ri_active->rs_visibleoffset = ri->ri_active->rs_dispoffset;
@@ -1906,7 +1907,6 @@ rasops_scrollback(void *v, void *cookie,
        struct rasops_info *ri = v;
        struct rasops_screen *scr = cookie;
        int row, col, oldvoff;
-       long attr;
 
        oldvoff = scr->rs_visibleoffset;
 
@@ -1927,7 +1927,7 @@ rasops_scrollback(void *v, void *cookie,
                return;
 
        rasops_cursor(ri, 0, 0, 0);
-       ri->ri_eraserows(ri, 0, ri->ri_rows, attr);
+       ri->ri_eraserows(ri, 0, ri->ri_rows, scr->rs_defattr);
        for (row = 0; row < ri->ri_rows; row++) {
                for (col = 0; col < ri->ri_cols; col++) {
                        int off = row * scr->rs_ri->ri_cols + col +