shithub: riscv

Info  •  Files  •  Log  •  Branches

mothra: fix integer overflow on textview scroll

--- a/sys/src/cmd/mothra/libpanel/textview.c

+++ b/sys/src/cmd/mothra/libpanel/textview.c

@@ -153,6 +153,7 @@

 	Textview *tp;

 	Rectangle r;

 	if(dir!=VERT) return;

+

 	tp=p->data;

 	ul=p->r.min;

 	size=subpt(p->r.max, p->r.min);

@@ -162,14 +163,14 @@

 		SET(yoffs);

 		break;

 	case 1:		/* left -- top moves to pointer */

-		yoffs=tp->yoffs-num*size.y/den;

+		yoffs=(vlong)tp->yoffs-num*size.y/den;

 		if(yoffs<0) yoffs=0;

 		break;

 	case 2:		/* middle -- absolute index of file */

-		yoffs=tp->thgt*num/den;

+		yoffs=(vlong)tp->thgt*num/den;

 		break;

 	case 4:		/* right -- line pointed at moves to top */

-		yoffs=tp->yoffs+num*size.y/den;

+		yoffs=tp->yoffs+(vlong)num*size.y/den;

 		if(yoffs>tp->thgt) yoffs=tp->thgt;

 		break;

 	}

@@ -177,7 +178,7 @@

 		pl_hiliteword(p, tp->hitword, 0);

 		r=pl_outline(p->b, p->r, p->state);

 		pl_rtredraw(p->b, r, tp->text, yoffs, tp->yoffs);

-		tp->yoffs=yoffs;

+		p->scr.pos.y=tp->yoffs=yoffs;

 		pl_fixtextview(p, tp, r);

 	}

 }

--- a/sys/src/cmd/mothra/mothra.c

+++ b/sys/src/cmd/mothra/mothra.c

@@ -171,7 +171,6 @@

 	if(s.pos.y > s.size.y)

 		s.pos.y = s.size.y;

 	plsetscroll(text, s);

-	pldraw(root, screen);

 }

 void mkpanels(void){