Do not use panic!s and assert!s for erroring

Fixes #29

Signed-off-by: Šimon Brandner <[email protected]>

Author: SimonBrandner

crates/oblichey-cli/src/camera/mod.rs

@@ -18,7 +18,7 @@ use v4l::{Device, FourCC};
 
 /// Some (at least mine) IR cameras occasionally produce very dark frames which we ignore
 const MAX_BRIGHTNESS_DECREASE: f32 = 24.0;
-/// How many times we are allowed to fail getting a frame before we panic
+/// How many times we are allowed to fail getting a frame before we return an error
 const MAX_FAILED_FRAMES_IN_ROW: u8 = 10;
 
 /// The type of a frame coming from the camera
@@ -79,7 +79,7 @@ pub struct Camera {
 impl Camera {
 	/// Creates a new Camera which can be used to get frames from the given device.
 	///
-	/// This is going to panic if a supported output pixel format cannot be found
+	/// This is going to return an error if a supported output pixel format cannot be found
 	pub fn new(camera_path: &str) -> Result<Self, Error> {
 		trace!("Creating Camera");
 
@@ -120,17 +120,20 @@ impl Camera {
 }
 
 /// Starts the camera loop
-pub fn start(frame: &Arc<Mutex<Option<Frame>>>, finished: &Arc<AtomicBool>, camera_path: &str) {
+pub fn start(
+	frame: &Arc<Mutex<Option<Frame>>>,
+	finished: &Arc<AtomicBool>,
+	camera_path: &str,
+) -> Result<(), String> {
 	let mut camera = match Camera::new(camera_path) {
 		Ok(c) => c,
-		Err(e) => panic!("Failed construct camera: {e}"),
+		Err(e) => return Err(format!("Failed to create camera: {e}")),
 	};
-
 	let mut failed_frames_in_row = 0;
 	let mut last_brightness = 255.0;
 	loop {
 		if finished.load(Ordering::SeqCst) {
-			return;
+			return Ok(());
 		}
 
 		let new_frame = match camera.get_frame() {
@@ -139,10 +142,9 @@ pub fn start(frame: &Arc<Mutex<Option<Frame>>>, finished: &Arc<AtomicBool>, came
 				error!("Failed to get frame: {e}");
 
 				failed_frames_in_row += 1;
-				assert!(
-					failed_frames_in_row < MAX_FAILED_FRAMES_IN_ROW,
-					"Failed to get {MAX_FAILED_FRAMES_IN_ROW} frames in row: {e}"
-				);
+				if failed_frames_in_row < MAX_FAILED_FRAMES_IN_ROW {
+					return Err(String::from("Failed to get too many frames in a row"));
+				}
 				continue;
 			}
 		};

crates/oblichey-cli/src/gui/mod.rs

@@ -55,7 +55,7 @@ pub fn start(
 	frame: Arc<Mutex<Option<Frame>>>,
 	faces: Arc<Mutex<Vec<FaceForGUI>>>,
 	finished: Arc<AtomicBool>,
-) {
+) -> Result<(), String> {
 	trace!("Creating GUI");
 
 	let event_loop_builder: Option<EventLoopBuilderHook> = Some(Box::new(|event_loop_builder| {
@@ -79,8 +79,10 @@ pub fn start(
 		},
 		Box::new(|_| Ok(Box::new(Gui::new(frame, faces, finished)))),
 	) {
-		panic!("Running eframe failed: {e}");
+		return Err(format!("Running eframe failed: {e}"));
 	};
+
+	Ok(())
 }
 
 struct Gui {

crates/oblichey-cli/src/main.rs

@@ -201,7 +201,7 @@ fn start_threads(
 	let finished_clone = finished.clone();
 	let camera_path_clone = config.camera.path.clone();
 	thread_handles.push(thread::spawn(move || {
-		camera::start(&frame_clone, &finished_clone, &camera_path_clone);
+		camera::start(&frame_clone, &finished_clone, &camera_path_clone)
 	}));
 
 	let faces_for_gui_clone = faces_for_gui.clone();
@@ -213,13 +213,13 @@ fn start_threads(
 			&faces_for_gui_clone,
 			&finished_clone,
 			&face_processor,
-		);
+		)
 	}));
 
 	if gui {
 		let finished_clone = finished.clone();
 		thread_handles.push(thread::spawn(move || {
-			gui::start(frame, faces_for_gui, finished_clone);
+			gui::start(frame, faces_for_gui, finished_clone)
 		}));
 	}
 
@@ -236,11 +236,17 @@ fn start_threads(
 
 	// Join all threads and print any errors
 	for thread_handle in thread_handles {
-		if let Err(e) = thread_handle.join() {
-			if let Some(panic_msg) = e.downcast_ref::<String>() {
-				println!("{panic_msg}");
-			} else {
-				println!("Thread panicked but with an unknown error");
+		match thread_handle.join() {
+			Ok(Ok(())) => (),
+			Ok(Err(e)) => {
+				log_and_print_error!("Thread returned an error: {e}");
+			}
+			Err(e) => {
+				if let Some(panic_msg) = e.downcast_ref::<String>() {
+					log_and_print_error!("Thread panicked: {panic_msg}");
+				} else {
+					log_and_print_error!("Thread panicked but with an unknown error");
+				}
 			}
 		}
 	}

crates/oblichey-cli/src/processors/mod.rs

@@ -19,12 +19,12 @@ pub fn start(
 	faces_for_gui: &Arc<Mutex<Vec<FaceForGUI>>>,
 	finished: &Arc<AtomicBool>,
 	face_processor: &Arc<Mutex<dyn FaceProcessor + Send + Sync>>,
-) {
+) -> Result<(), String> {
 	let frame_processor = FrameProcessor::new();
 
 	loop {
 		if finished.load(Ordering::SeqCst) {
-			return;
+			return Ok(());
 		}
 
 		let frame_lock = match frame.lock() {
@@ -44,7 +44,7 @@ pub fn start(
 		};
 		let new_faces_for_gui = face_processor_lock.process_faces(faces_for_processing);
 		if face_processor_lock.is_finished() {
-			return;
+			return Ok(());
 		}
 		drop(face_processor_lock);