static long hidraw_ioctl()

in hidraw.c [363:492]

• 116 lines of code
• 28 McCabe index (conditional complexity)

static long hidraw_ioctl(struct file *file, unsigned int cmd,
							unsigned long arg)
{
	struct inode *inode = file_inode(file);
	unsigned int minor = iminor(inode);
	long ret = 0;
	struct hidraw *dev;
	void __user *user_arg = (void __user*) arg;

	down_read(&minors_rwsem);
	dev = hidraw_table[minor];
	if (!dev || !dev->exist) {
		ret = -ENODEV;
		goto out;
	}

	switch (cmd) {
		case HIDIOCGRDESCSIZE:
			if (put_user(dev->hid->rsize, (int __user *)arg))
				ret = -EFAULT;
			break;

		case HIDIOCGRDESC:
			{
				__u32 len;

				if (get_user(len, (int __user *)arg))
					ret = -EFAULT;
				else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
					ret = -EINVAL;
				else if (copy_to_user(user_arg + offsetof(
					struct hidraw_report_descriptor,
					value[0]),
					dev->hid->rdesc,
					min(dev->hid->rsize, len)))
					ret = -EFAULT;
				break;
			}
		case HIDIOCGRAWINFO:
			{
				struct hidraw_devinfo dinfo;

				dinfo.bustype = dev->hid->bus;
				dinfo.vendor = dev->hid->vendor;
				dinfo.product = dev->hid->product;
				if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
					ret = -EFAULT;
				break;
			}
		default:
			{
				struct hid_device *hid = dev->hid;
				if (_IOC_TYPE(cmd) != 'H') {
					ret = -EINVAL;
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
					break;
				}
				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSINPUT(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
					break;
				}
				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGINPUT(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSOUTPUT(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
					break;
				}
				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGOUTPUT(0))) {
					int len = _IOC_SIZE(cmd);
					ret = hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
					break;
				}

				/* Begin Read-only ioctls. */
				if (_IOC_DIR(cmd) != _IOC_READ) {
					ret = -EINVAL;
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
					int len = strlen(hid->name) + 1;
					if (len > _IOC_SIZE(cmd))
						len = _IOC_SIZE(cmd);
					ret = copy_to_user(user_arg, hid->name, len) ?
						-EFAULT : len;
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
					int len = strlen(hid->phys) + 1;
					if (len > _IOC_SIZE(cmd))
						len = _IOC_SIZE(cmd);
					ret = copy_to_user(user_arg, hid->phys, len) ?
						-EFAULT : len;
					break;
				}

				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWUNIQ(0))) {
					int len = strlen(hid->uniq) + 1;
					if (len > _IOC_SIZE(cmd))
						len = _IOC_SIZE(cmd);
					ret = copy_to_user(user_arg, hid->uniq, len) ?
						-EFAULT : len;
					break;
				}
			}

		ret = -ENOTTY;
	}
out:
	up_read(&minors_rwsem);
	return ret;
}