Safer handling of DeviceType value coming from FFI

includes/wooting-analog-common.h

@@ -130,7 +130,7 @@ typedef struct WootingAnalog_DeviceInfo_FFI {
    */
   WootingAnalog_DeviceID device_id;
   /**
-   * Hardware type of the Device
+   * Hardware type of the Device see `DeviceType` enum
    */
-  enum WootingAnalog_DeviceType device_type;
+  WootingAnalog_DeviceType device_type;
 } WootingAnalog_DeviceInfo_FFI;

wooting-analog-common/cbindgen.toml

@@ -4,17 +4,25 @@ header = "/* This is a generated header file providing the common items to every
 autogen_warning = "/* Warning, this file is autogenerated by cbindgen. Don't modify this manually. */"
 
 [export]
-include = ["DeviceInfoBlank", "DeviceInfo_FFI", "DeviceEventType", "WootingAnalogResult", "KeycodeType"]
+include = [
+    "DeviceInfoBlank",
+    "DeviceInfo_FFI",
+    "DeviceEventType",
+    "WootingAnalogResult",
+    "KeycodeType",
+    "DeviceType",
+]
 prefix = "WootingAnalog_"
 renaming_overrides_prefixing = true
 item_types = ["enums", "structs", "typedefs", "functions", "opaque"]
 
 [export.rename]
 "FfiStr" = "const char*"
 "WootingAnalogResult" = "WootingAnalogResult"
+"DeviceType_FFI" = "WootingAnalog_DeviceType"
 
 [parse]
 expand = ["wooting-analog-common"]
 
 [enum]
-prefix_with_name=true
+prefix_with_name = true

wooting-analog-common/src/lib.rs

@@ -39,6 +39,12 @@ pub struct DeviceInfo {
     pub device_type: DeviceType,
 }
 
+// We do this little alias so that we can force cbindgen to rename it to point to the DeviceType enum.
+// For the rust side, we want to have it as a c_int so we can ensure it's valid and within bounds.
+// As just taking it as the enum straight up can cause undefined behaviour if an invalid value is provided
+/// cbindgen:ignore
+type DeviceType_FFI = c_int;
+
 /// The core `DeviceInfo` struct which contains all the interesting information
 /// for a particular device. This is the version which the consumer of the SDK will receive
 /// through the wrapper. This is not for use in the Internal workings of the SDK, that is what
@@ -55,8 +61,8 @@ pub struct DeviceInfo_FFI {
     pub device_name: *mut c_char,
     /// Unique device ID, which should be generated using `generate_device_id`
     pub device_id: DeviceID,
-    /// Hardware type of the Device
-    pub device_type: DeviceType,
+    /// Hardware type of the Device see `DeviceType` enum
+    pub device_type: DeviceType_FFI,
 }
 
 impl From<DeviceInfo> for DeviceInfo_FFI {
@@ -67,7 +73,7 @@ impl From<DeviceInfo> for DeviceInfo_FFI {
             manufacturer_name: CString::new(device.manufacturer_name).unwrap().into_raw(),
             device_name: CString::new(device.device_name).unwrap().into_raw(),
             device_id: device.device_id,
-            device_type: device.device_type,
+            device_type: device.device_type as c_int,
         }
     }
 }
@@ -84,6 +90,14 @@ impl Drop for DeviceInfo_FFI {
 
 impl DeviceInfo_FFI {
     pub fn into_device_info(&self) -> DeviceInfo {
+        let device_type = DeviceType::from_i32(self.device_type);
+        if device_type.is_none() {
+            log::error!(
+                "Invalid Device Type when converting DeviceInfo_FFI into DeviceInfo: {}",
+                self.device_type
+            );
+        }
+
         DeviceInfo {
             vendor_id: self.vendor_id.clone(),
             product_id: self.product_id.clone(),
@@ -102,7 +116,7 @@ impl DeviceInfo_FFI {
                     .to_owned()
             },
             device_id: self.device_id.clone(),
-            device_type: self.device_type.clone(),
+            device_type: device_type.unwrap_or(DeviceType::Other),
         }
     }
 }