Checkpoint

usb/endpoint.go

@@ -0,0 +1,86 @@
+package usb
+
+// #include <libusb-1.0/libusb.h>
+import "C"
+
+import (
+	"fmt"
+	"reflect"
+	"unsafe"
+	"time"
+)
+
+type Endpoint interface {
+	Read(b []byte) (int, error)
+	Write(b []byte) (int, error)
+	Interface() InterfaceSetup
+	Info() EndpointInfo
+}
+
+type endpoint struct {
+	*Device
+	InterfaceSetup
+	EndpointInfo
+	xfer func(*endpoint, []byte, time.Duration) (int, error)
+}
+
+func (e *endpoint) Read(buf []byte) (int, error) {
+	if EndpointDirection(e.Address) & ENDPOINT_DIR_MASK != ENDPOINT_DIR_OUT {
+		return 0, fmt.Errorf("usb: read: not an IN endpoint")
+	}
+
+	return e.xfer(e, buf, e.ReadTimeout)
+}
+
+func (e *endpoint) Write(buf []byte) (int, error) {
+	if EndpointDirection(e.Address) & ENDPOINT_DIR_MASK != ENDPOINT_DIR_OUT {
+		return 0, fmt.Errorf("usb: write: not an OUT endpoint")
+	}
+
+	return e.xfer(e, buf, e.WriteTimeout)
+}
+
+func (e *endpoint) Interface() InterfaceSetup { return InterfaceSetup{} }
+func (e *endpoint) Info() EndpointInfo { return EndpointInfo{} }
+
+// TODO(kevlar): (*Endpoint).Close
+
+func bulk_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
+	if len(buf) == 0 {
+		return 0, nil
+	}
+
+	data := (*reflect.SliceHeader)(unsafe.Pointer(&buf)).Data
+
+	var cnt C.int
+	if errno := C.libusb_bulk_transfer(
+		e.handle,
+		C.uchar(e.Address),
+		(*C.uchar)(unsafe.Pointer(data)),
+		C.int(len(buf)),
+		&cnt,
+		C.uint(timeout/time.Millisecond)); errno < 0 {
+		return 0, usbError(errno)
+	}
+	return int(cnt), nil
+}
+
+func interrupt_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
+	if len(buf) == 0 {
+		return 0, nil
+	}
+
+	data := (*reflect.SliceHeader)(unsafe.Pointer(&buf)).Data
+
+	var cnt C.int
+	if errno := C.libusb_interrupt_transfer(
+		e.handle,
+		C.uchar(e.Address),
+		(*C.uchar)(unsafe.Pointer(data)),
+		C.int(len(buf)),
+		&cnt,
+		C.uint(timeout/time.Millisecond)); errno < 0 {
+		return 0, usbError(errno)
+	}
+	return int(cnt), nil
+}