From bf3b23ccd2986ffafe48bcc57d65b79b8a96ce4b Mon Sep 17 00:00:00 2001
From: Sebastian Zagrodzki <sebek@zagrodzki.net>
Date: Thu, 23 Feb 2017 10:45:35 +0100
Subject: [PATCH] move all transfer C parts to libusb.go to alloc()

---
 usb/libusb.go   |  9 +++++++--
 usb/transfer.go | 11 ++---------
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/usb/libusb.go b/usb/libusb.go
index 00951d4..d5412a9 100644
--- a/usb/libusb.go
+++ b/usb/libusb.go
@@ -71,7 +71,7 @@ type libusbIntf interface {
 	setAlt(*libusbDevHandle, uint8, uint8) error
 
 	// endpoint
-	alloc(*libusbDevHandle, int) (*libusbTransfer, error)
+	alloc(*libusbDevHandle, uint8, TransferType, time.Duration, int, []byte) (*libusbTransfer, error)
 	cancel(*libusbTransfer) error
 	submit(*libusbTransfer) error
 	free(*libusbTransfer)
@@ -327,13 +327,18 @@ func (libusbImpl) setAlt(d *libusbDevHandle, iface, setup uint8) error {
 	return fromUSBError(C.libusb_set_interface_alt_setting((*C.libusb_device_handle)(d), C.int(iface), C.int(setup)))
 }
 
-func (libusbImpl) alloc(d *libusbDevHandle, isoPackets int) (*libusbTransfer, error) {
+func (libusbImpl) alloc(d *libusbDevHandle, addr uint8, tt TransferType, timeout time.Duration, isoPackets int, buf []byte) (*libusbTransfer, error) {
 	xfer := C.libusb_alloc_transfer(C.int(isoPackets))
 	if xfer == nil {
 		return nil, fmt.Errorf("libusb_alloc_transfer(%d) failed", isoPackets)
 	}
 	xfer.dev_handle = (*C.libusb_device_handle)(d)
+	xfer.endpoint = C.uchar(addr)
+	xfer.timeout = C.uint(timeout / time.Millisecond)
+	xfer._type = C.uchar(tt)
 	xfer.num_iso_packets = C.int(isoPackets)
+	xfer.buffer = (*C.uchar)((unsafe.Pointer)(&buf[0]))
+	xfer.length = C.int(len(buf))
 	return (*libusbTransfer)(xfer), nil
 }
 
diff --git a/usb/transfer.go b/usb/transfer.go
index 81f3da7..fcc0afb 100644
--- a/usb/transfer.go
+++ b/usb/transfer.go
@@ -133,24 +133,17 @@ func newUSBTransfer(dev *libusbDevHandle, ei EndpointInfo, buf []byte, timeout t
 		}
 	}
 
-	xfer, err := libusb.alloc(dev, isoPackets)
+	xfer, err := libusb.alloc(dev, ei.Address, tt, timeout, isoPackets, buf)
 	if err != nil {
 		return nil, err
 	}
 
-	xfer.timeout = C.uint(timeout / time.Millisecond)
-	xfer.endpoint = C.uchar(ei.Address)
-	xfer._type = C.uchar(tt)
-
-	xfer.buffer = (*C.uchar)((unsafe.Pointer)(&buf[0]))
-	xfer.length = C.int(len(buf))
-
 	if tt == TRANSFER_TYPE_ISOCHRONOUS {
 		libusb.setIsoPacketLengths(xfer, ei.MaxIsoPacket)
 	}
 
 	t := &usbTransfer{
-		xfer: (*libusbTransfer)(xfer),
+		xfer: xfer,
 		buf:  buf,
 	}
 	runtime.SetFinalizer(t, func(t *usbTransfer) {