commit 99f78fa553f9ddb23fab73e47a408d66ca7f974c
from: Hiltjo Posthuma <hiltjo@codemadness.org>
date: Fri Nov  3 20:14:58 2017 UTC

gettextprop: check result of XGetTextProperty (undefined behaviour for XFree)

commit - a9b6a312a77b9cc81ca8b08a95c09e9f7948d7a6
commit + 99f78fa553f9ddb23fab73e47a408d66ca7f974c
blob - b0d99c05ffed432638a943610625fa5adbbfb400
blob + 650d19f8ebe0d07160ed5a1f79d6b267eb6baf52
--- dwm.c
+++ dwm.c
@@ -910,8 +910,7 @@ gettextprop(Window w, Atom atom, char *text, unsigned 
 	if (!text || size == 0)
 		return 0;
 	text[0] = '\0';
-	XGetTextProperty(dpy, w, &name, atom);
-	if (!name.nitems)
+	if (!XGetTextProperty(dpy, w, &name, atom) || !name.nitems)
 		return 0;
 	if (name.encoding == XA_STRING)
 		strncpy(text, (char *)name.value, size - 1);