From 212b4456282afc1100643beebb861155002ac62e Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Fri, 6 Sep 2019 01:37:00 +0200
Subject: [PATCH] Shuttle Surface: handle libusb_init() failure

USB stack may not be available on some systems, e.g. unit-test VM.
When libusb_init(0) fails to create default context, further calls
into the libusb API will cause segfaults.
---
 libs/surfaces/contourdesign/contourdesign.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libs/surfaces/contourdesign/contourdesign.cc b/libs/surfaces/contourdesign/contourdesign.cc
index ac7ed0b536..1e4471b56b 100644
--- a/libs/surfaces/contourdesign/contourdesign.cc
+++ b/libs/surfaces/contourdesign/contourdesign.cc
@@ -89,7 +89,11 @@ ContourDesignControlProtocol::~ContourDesignControlProtocol ()
 bool
 ContourDesignControlProtocol::probe ()
 {
-	return true;
+	bool rv = LIBUSB_SUCCESS == libusb_init (0);
+	if (rv) {
+		libusb_exit (0);
+	}
+	return rv;
 }
 
 void*