libusb: fix a crash with picolcd driver.

The implementation of libusb is not complete, and the missing functions
can lead to crashes. At least stub out this one, which is enough to get
the picolcd working.

dev-libs/libusb/libusb-1.0.21.recipe

@@ -20,9 +20,10 @@ COPYRIGHT="2001 Johannes Erdfelt
 	2012-2013 Toby Gray
 	2013-2015 Chris Dickens"
 LICENSE="GNU LGPL v2.1"
-REVISION="2"
+REVISION="3"
 SOURCE_URI="https://github.com/libusb/libusb/archive/v$portVersion.tar.gz"
 SOURCE_FILENAME="libusb-$portVersion.tar.gz"
+PATCHES="libusb-$portVersion.patchset"
 CHECKSUM_SHA256="1a5b08c05bc5e38c81c2d59c29954d5916646f4ff46f51381b3f624384e4ac01"
 ARCHITECTURES="x86 x86_64 x86_gcc2"
 SECONDARY_ARCHITECTURES="x86_gcc2 x86"

dev-libs/libusb/patches/libusb-1.0.21.patchset

@@ -0,0 +1,37 @@
+From 6272b5474073c90978488ec441270ed3511c09b4 Mon Sep 17 00:00:00 2001
+From: Adrien Destugues <pulkomandy@pulkomandy.tk>
+Date: Fri, 14 Jul 2017 14:51:19 +0200
+Subject: Add a stub for clear_halt.
+
+Fixes a crash in picolcd driver.
+
+diff --git a/libusb/os/haiku_usb_raw.cpp b/libusb/os/haiku_usb_raw.cpp
+index 77adbd1..44bf4c3 100644
+--- a/libusb/os/haiku_usb_raw.cpp
++++ b/libusb/os/haiku_usb_raw.cpp
+@@ -128,6 +128,13 @@ haiku_set_altsetting(struct libusb_device_handle *dev_handle, int interface_numb
+ }
+ 
+ static int
++haiku_clear_halt(libusb_device_handle*, unsigned char)
++{
++	/* TODO */
++	return 0;
++}
++
++static int
+ haiku_release_interface(struct libusb_device_handle *dev_handle, int interface_number)
+ {
+ 	USBDeviceHandle *handle = *((USBDeviceHandle **)dev_handle->os_priv);
+@@ -216,7 +223,7 @@ const struct usbi_os_backend haiku_usb_raw_backend = {
+ 	/*.release_interface =*/ haiku_release_interface,
+ 
+ 	/*.set_interface_altsetting =*/ haiku_set_altsetting,
+-	/*.clear_halt =*/ NULL,
++	/*.clear_halt =*/ haiku_clear_halt,
+ 	/*.reset_device =*/ NULL,
+ 
+ 	/*.alloc_streams =*/ NULL,
+-- 
+2.7.0
+