Add static assertions for Request and Response size

The Request and Response types have to have a size of 64 bytes.
Previously, we only verified this property by visual inspection.
Accidental changes to the size could lead to runtime errors.  This patch
adds static assertions using the static_assertions crate to enforce this
property at compile time.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/device.rs b/src/device.rs
index b25cfb7..8f6f6ef 100644
--- a/src/device.rs
+++ b/src/device.rs
@@ -3,6 +3,7 @@
 
 use serde::{Deserialize, Serialize};
 use serde_big_array::big_array;
+use static_assertions::assert_eq_size;
 use usb_device::bus::{UsbBus, UsbBusAllocator};
 use usb_device::device::{UsbDevice, UsbDeviceBuilder, UsbVidPid};
 
@@ -65,6 +66,8 @@ struct Request {
     pub crc: u32,
 }
 
+assert_eq_size!(request; [u8; REPORT_LEN], Request);
+
 #[derive(Serialize)]
 struct Response {
     pub device_status: DeviceStatus,
@@ -76,6 +79,8 @@ struct Response {
     pub crc: u32,
 }
 
+assert_eq_size!(response; [u8; REPORT_LEN], Response);
+
 impl Response {
     fn new(device_status: DeviceStatus, command_id: u8, last_crc: u32) -> Response {
         Response {