usb_osx.c

Android 一些工具

    kr = IOCreatePlugInInterfaceForService(device,
            kIOUSBDeviceUserClientTypeID,
            kIOCFPlugInInterfaceID,
            &plugin, &score);

    if ((kr != 0) || (plugin == NULL)) {
        ERR("Unable to create a plug-in (%08x)\n", kr);
        goto error;
    }

    // Now create the device interface.
    result = (*plugin)->QueryInterface(plugin,
            CFUUIDGetUUIDBytes(kIOUSBDeviceInterfaceID), (LPVOID) &dev);
    if ((result != 0) || (dev == NULL)) {
        ERR("Couldn't create a device interface (%08x)\n", (int) result);
        goto error;
    }

    /* 
     * We don't need the intermediate interface after the device interface
     * is created.
     */
    IODestroyPlugInInterface(plugin);

    // So, we have a device, finally. Grab its vitals.

    kr = (*dev)->GetDeviceVendor(dev, &handle->info.dev_vendor);
    if (kr != 0) {
        ERR("GetDeviceVendor");
        goto error;
    }

    kr = (*dev)->GetDeviceProduct(dev, &handle->info.dev_product);
    if (kr != 0) {
        ERR("GetDeviceProduct");
        goto error;
    }

    kr = (*dev)->GetDeviceClass(dev, &handle->info.dev_class);
    if (kr != 0) {
        ERR("GetDeviceClass");
        goto error;
    }

    kr = (*dev)->GetDeviceSubClass(dev, &handle->info.dev_subclass);
    if (kr != 0) {
        ERR("GetDeviceSubClass");
        goto error;
    }

    kr = (*dev)->GetDeviceProtocol(dev, &handle->info.dev_protocol);
    if (kr != 0) {
        ERR("GetDeviceProtocol");
        goto error;
    }

    kr = (*dev)->USBGetSerialNumberStringIndex(dev, &serialIndex);

    if (serialIndex > 0) {
        IOUSBDevRequest req;
        UInt16  buffer[256];

        req.bmRequestType = USBmakebmRequestType(kUSBIn, kUSBStandard, kUSBDevice);
        req.bRequest = kUSBRqGetDescriptor;
        req.wValue = (kUSBStringDesc << 8) | serialIndex;
        req.wIndex = 0;
        req.pData = buffer;
        req.wLength = sizeof(buffer);
        kr = (*dev)->DeviceRequest(dev, &req);

        if (kr == kIOReturnSuccess && req.wLenDone > 0) {
            int i, count;
            
            // skip first word, and copy the rest to the serial string, changing shorts to bytes.
            count = (req.wLenDone - 1) / 2;
            for (i = 0; i < count; i++)
              handle->info.serial_number[i] = buffer[i + 1];
            handle->info.serial_number[i] = 0;
        }
    } else {
        // device has no serial number
        handle->info.serial_number[0] = 0;
    }

    if (try_interfaces(dev, handle)) {
        goto error;
    }

    (*dev)->Release(dev);
    return 0;

    error:

    if (dev != NULL) {
        (*dev)->Release(dev);
    }
    
    return -1;    
}


/** Initializes the USB system. Returns 0 on success, -1 on error. */
static int init_usb(ifc_match_func callback, usb_handle **handle) {
    int ret = -1;
    CFMutableDictionaryRef matchingDict;
    kern_return_t result;
    io_iterator_t iterator;
    usb_handle h;

    h.success = 0;
    h.callback = callback;

    /*
     * Create our matching dictionary to find appropriate devices.
     * IOServiceAddMatchingNotification consumes the reference, so we
     * do not need to release it.
     */
    matchingDict = IOServiceMatching(kIOUSBDeviceClassName);

    if (matchingDict == NULL) {
        ERR("Couldn't create USB matching dictionary.\n");
        return -1;
    }

    result = IOServiceGetMatchingServices(
            kIOMasterPortDefault, matchingDict, &iterator);

    if (result != 0) {
        ERR("Could not create iterator.");
        return -1;
    }
    
    for (;;) {
        if (! IOIteratorIsValid(iterator)) {
            /*
             * Apple documentation advises resetting the iterator if
             * it should become invalid during iteration.
             */
            IOIteratorReset(iterator);
            continue;
        }
                
        io_service_t device = IOIteratorNext(iterator);

        if (device == 0) {
            break;
        }

        usb_ifc_info info;

        if (try_device(device, &h) != 0) {
            IOObjectRelease(device);
            ret = -1;
            break;
        }

        if (h.success) {
            *handle = calloc(1, sizeof(usb_handle));
            memcpy(*handle, &h, sizeof(usb_handle));
            ret = 0;
            break;
        }

        IOObjectRelease(device);
    }

    IOObjectRelease(iterator);

    return ret;
}



/*
 * Definitions of this file's public functions.
 */

usb_handle *usb_open(ifc_match_func callback) {
    usb_handle *handle = NULL;

    if (init_usb(callback, &handle) < 0) {
        /* Something went wrong initializing USB. */
        return NULL;
    }

    return handle;
}

int usb_close(usb_handle *h) {
    /* TODO: Something better here? */
    return 0;
}

int usb_read(usb_handle *h, void *data, int len) {
    IOReturn result;
    UInt32 numBytes = len;

    if (len == 0) {
        return 0;
    }

    if (h == NULL) {
        return -1;
    }

    if (h->interface == NULL) {
        ERR("usb_read interface was null\n");
        return -1;
    }

    if (h->bulkIn == 0) {
        ERR("bulkIn endpoint not assigned\n");
        return -1;
    }

    result = (*h->interface)->ReadPipe(
            h->interface, h->bulkIn, data, &numBytes);

    if (result == 0) {
        return (int) numBytes;
    } else {
        ERR("usb_read failed with status %x\n", result);
    }

    return -1;
}

int usb_write(usb_handle *h, const void *data, int len) {
    IOReturn result;

    if (len == 0) {
        return 0;
    }

    if (h == NULL) {
        return -1;
    }

    if (h->interface == NULL) {
        ERR("usb_write interface was null\n");
        return -1;
    }

    if (h->bulkOut == 0) {
        ERR("bulkOut endpoint not assigned\n");
        return -1;
    }

    result = (*h->interface)->WritePipe(
            h->interface, h->bulkOut, (void *)data, len);

    #if 0
    if ((result == 0) && (h->zero_mask)) {
        /* we need 0-markers and our transfer */
        if(!(len & h->zero_mask)) {
            result = (*h->interface)->WritePipe(
                    h->interface, h->bulkOut, (void *)data, 0);
        }
    }
    #endif

    if (result != 0) {
        ERR("usb_write failed with status %x\n", result);
        return -1;
    }

    return len;
}