Add get_firmware_version method

This patch combines the get_{major,minor}_firmware_version methods into
the new get_firmware_version method that returns a FirmwareVersion
struct.  Currently, this requires casting from i32 to u8.  But this will
be fixed with the next libnitrokey version as we change the return types
for the firmware getters.

3 files changed, 20 insertions, 33 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 25a8c31..c51727e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@ SPDX-License-Identifier: MIT
 - Implement `From<(T: Device, Error)>` for `Error`.
 - Fix timing issues with the `totp_no_pin` and `totp_pin` test cases.
 - Always return a `Result` in functions that communicate with a device.
+- Combine `get_{major,minor}_firmware_version` into `get_firmware_version`.
 
 # v0.3.4 (2019-01-20)
 - Fix authentication methods that assumed that `char` is signed.
diff --git a/src/device.rs b/src/device.rs
index 4178922..2fac4f2 100644
--- a/src/device.rs
+++ b/src/device.rs
@@ -379,7 +379,7 @@ pub trait Device: Authenticate + GetPasswordSafe + GenerateOtp + fmt::Debug {
         result_or_error(unsafe { nitrokey_sys::NK_get_admin_retry_count() })
     }
 
-    /// Returns the major part of the firmware version (should be zero).
+    /// Returns the firmware version.
     ///
     /// # Example
     ///
@@ -389,37 +389,24 @@ pub trait Device: Authenticate + GetPasswordSafe + GenerateOtp + fmt::Debug {
     ///
     /// # fn try_main() -> Result<(), Error> {
     /// let device = nitrokey::connect()?;
-    /// println!(
-    ///     "Firmware version: {}.{}",
-    ///     device.get_major_firmware_version().unwrap(),
-    ///     device.get_minor_firmware_version().unwrap(),
-    /// );
+    /// match device.get_firmware_version() {
+    ///     Ok(version) => println!("Firmware version: {}", version),
+    ///     Err(err) => println!("Could not access firmware version: {}", err),
+    /// };
     /// #     Ok(())
     /// # }
     /// ```
-    fn get_major_firmware_version(&self) -> Result<i32, Error> {
-        result_or_error(unsafe { nitrokey_sys::NK_get_major_firmware_version() })
-    }
-
-    /// Returns the minor part of the firmware version (for example 8 for version 0.8).
-    ///
-    /// # Example
-    ///
-    /// ```no_run
-    /// use nitrokey::Device;
-    /// # use nitrokey::Error;
-    ///
-    /// # fn try_main() -> Result<(), Error> {
-    /// let device = nitrokey::connect()?;
-    /// println!(
-    ///     "Firmware version: {}.{}",
-    ///     device.get_major_firmware_version().unwrap(),
-    ///     device.get_minor_firmware_version().unwrap(),
-    /// );
-    /// #     Ok(())
-    /// # }
-    fn get_minor_firmware_version(&self) -> Result<i32, Error> {
-        result_or_error(unsafe { nitrokey_sys::NK_get_minor_firmware_version() })
+    fn get_firmware_version(&self) -> Result<FirmwareVersion, Error> {
+        let major = result_or_error(unsafe { nitrokey_sys::NK_get_major_firmware_version() })?;
+        let minor = result_or_error(unsafe { nitrokey_sys::NK_get_minor_firmware_version() })?;
+        let max = i32::from(u8::max_value());
+        if major < 0 || minor < 0 || major > max || minor > max {
+            return Err(Error::UnexpectedError);
+        }
+        Ok(FirmwareVersion {
+            major: major as u8,
+            minor: minor as u8,
+        })
     }
 
     /// Returns the current configuration of the Nitrokey device.
diff --git a/tests/device.rs b/tests/device.rs
index 7ab4d66..d80f011 100644
--- a/tests/device.rs
+++ b/tests/device.rs
@@ -95,10 +95,9 @@ fn get_serial_number(device: DeviceWrapper) {
 }
 #[test_device]
 fn get_firmware_version(device: Pro) {
-    assert_ok!(0, device.get_major_firmware_version());
-    let minor = device.get_minor_firmware_version();
-    assert!(minor.is_ok());
-    assert!(minor.unwrap() > 0);
+    let version = device.get_firmware_version().unwrap();
+    assert_eq!(0, version.major);
+    assert!(version.minor > 0);
 }
 
 fn admin_retry<T: Authenticate + Device>(device: T, suffix: &str, count: u8) -> T {