source: mainline/uspace/lib/usbvirt/src/ctrltransfer.c@ 84b240f

#include "private.h"
#include <usb/request.h>
#include <usb/debug.h>
#include <assert.h>
#include <errno.h>

int process_control_transfer(usbvirt_device_t *dev,
    usbvirt_control_request_handler_t *control_handlers,
    usb_device_request_setup_packet_t *setup,
    uint8_t *data, size_t *data_sent_size)
{
        assert(dev);
        assert(setup);

        if (control_handlers == NULL) {
                return EFORWARD;
        }

        usb_direction_t direction = setup->request_type & 128 ?
            USB_DIRECTION_IN : USB_DIRECTION_OUT;
        usb_request_recipient_t req_recipient = setup->request_type & 31;
        usb_request_type_t req_type = (setup->request_type >> 5) & 3;

        usbvirt_control_request_handler_t *handler = control_handlers;
        while (handler->callback != NULL) {
                if (handler->req_direction != direction) {
                        goto next;
                }
                if (handler->req_recipient != req_recipient) {
                        goto next;
                }
                if (handler->req_type != req_type) {
                        goto next;
                }
                if (handler->request != setup->request) {
                        goto next;
                }

                usb_log_debug("Control transfer: %s(%s)\n", handler->name,
                    usb_debug_str_buffer((uint8_t*) setup, sizeof(*setup), 0));
                int rc = handler->callback(dev, setup, data, data_sent_size);
                if (rc == EFORWARD) {
                        goto next;
                }

                return rc;

next:
                handler++;
        }

        return EFORWARD;
}