Externals: update libusb to version 1.0.19

Externals/libusb/msvc/missing.h

@@ -0,0 +1,32 @@
+/*
+ * Header file for missing WinCE functionality
+ * Copyright © 2012-2013 RealVNC Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef MISSING_H
+#define MISSING_H
+
+/* Windows CE doesn't have SleepEx() - Fallback to Sleep() */
+#define SleepEx(m, a) Sleep(m)
+
+/* Windows CE doesn't have any APIs to query environment variables.
+ *
+ * This contains a registry based implementation of getenv.
+ */
+char *getenv(const char *name);
+
+#endif