commit 6818e07291f3b2913e687c8ec3d3fe4711724050
from: NRK <nrk@disroot.org>
via: Hiltjo Posthuma <hiltjo@codemadness.org>
date: Fri Mar 25 21:53:50 2022 UTC

avoid redraw when there's no change

while i was timing the performance issue, i noticed that there was lots
of random redrawing going on.

turns out there were coming from here; if someone presses CTRL/ALT etc
without pressing anything else, nothing will be inserted, so nothing
will change. but the code will `break`, go down and do a needless redraw.

this patch changes it to simply return if the keypress iscntrl()

also avoid potential UB by casting *buf into an unsigned char.

commit - b43ec0577f2ad8ad33a0b893fe5360d966036786
commit + 6818e07291f3b2913e687c8ec3d3fe4711724050
blob - 085dc292631e72778c05c31f4c4840d9ab0b0856
blob + 19f6385367133c72bccb2432f549b0a5466497aa
--- dmenu.c
+++ dmenu.c
@@ -415,8 +415,9 @@ keypress(XKeyEvent *ev)
 	switch(ksym) {
 	default:
 insert:
-		if (!iscntrl(*buf))
-			insert(buf, len);
+		if (iscntrl((unsigned char)*buf))
+			return;
+		insert(buf, len);
 		break;
 	case XK_Delete:
 	case XK_KP_Delete: