From 54165a84754ce51c88cabcc585647ef28b6ee1a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mario=20H=C3=BCttel?= <mario.huettel@gmx.net>
Date: Sun, 12 May 2019 14:16:36 +0200
Subject: [PATCH] conv-settings-dialog: harden number2eng function against null
 pointer

---
 widgets/conv-settings-dialog.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/widgets/conv-settings-dialog.c b/widgets/conv-settings-dialog.c
index 7884cb2..b502bc5 100644
--- a/widgets/conv-settings-dialog.c
+++ b/widgets/conv-settings-dialog.c
@@ -191,6 +191,10 @@ static double convert_number_to_engineering(double input, const char **out_prefi
 					1E2, 1E3, 1E6, 1E9, 1E12, 1E15, 1E18, 1E21, 1E24};
 	const int prefix_count = (int)(sizeof(prefixes)/sizeof(char *));
 
+	/* If pointer is invalid, return NaN */
+	if (!out_prefix)
+		return 0.0 / 0.0;
+
 	/* Start with the 2nd smallest prefix */
 	for (idx = 1; idx < prefix_count; idx++) {
 		if (input < scale[idx]) {