static int udev_builtin_hwdb_search(struct udev_device *dev, struct udev_device *srcdev,
                                    const char *subsystem, const char *prefix,
                                    const char *filter, bool test) {
        struct udev_device *d;
        char s[16];
        bool last = false;
        int r = 0;

        assert(dev);

        if (!srcdev)
                srcdev = dev;

        for (d = srcdev; d && !last; d = udev_device_get_parent(d)) {
                const char *dsubsys;
                const char *modalias = NULL;

                dsubsys = udev_device_get_subsystem(d);
                if (!dsubsys)
                        continue;

                /* look only at devices of a specific subsystem */
                if (subsystem && !streq(dsubsys, subsystem))
                        continue;

                modalias = udev_device_get_property_value(d, "MODALIAS");

                if (streq(dsubsys, "usb") && streq_ptr(udev_device_get_devtype(d), "usb_device")) {
                        /* if the usb_device does not have a modalias, compose one */
                        if (!modalias)
                                modalias = modalias_usb(d, s, sizeof(s));

                        /* avoid looking at any parent device, they are usually just a USB hub */
                        last = true;
                }

                if (!modalias)
                        continue;

                r = udev_builtin_hwdb_lookup(dev, prefix, modalias, filter, test);
                if (r > 0)
                        break;
        }

        return r;
}
static int udev_builtin_hwdb_search(struct udev_device *dev, struct udev_device *srcdev,
                                    const char *subsystem, const char *prefix,
                                    const char *filter, bool test) {
        struct udev_device *d;
        char s[16];
        int n = 0;

        for (d = srcdev; d; d = udev_device_get_parent(d)) {
                const char *dsubsys;
                const char *modalias = NULL;

                dsubsys = udev_device_get_subsystem(d);
                if (!dsubsys)
                        continue;

                /* look only at devices of a specific subsystem */
                if (subsystem && !streq(dsubsys, subsystem))
                        continue;

                /* the usb_device does not have a modalias, compose one */
                if (streq(dsubsys, "usb"))
                        modalias = modalias_usb(d, s, sizeof(s));

                if (!modalias)
                        modalias = udev_device_get_property_value(d, "MODALIAS");

                if (!modalias)
                        continue;

                n = udev_builtin_hwdb_lookup(dev, prefix, modalias, filter, test);
                if (n > 0)
                        break;
        }

        return n;
}