video: add tests

Add test for all modules, with dev-dependencies
(including rstest [1] for parametrized tests), and
infrastructure.

[1] - https://docs.rs/rstest/latest/rstest/

Signed-off-by: Albert Esteve <[email protected]>

crates/video/src/main.rs

@@ -121,3 +121,76 @@ fn main() -> Result<()> {
 
     start_backend(VuVideoConfig::try_from(VideoArgs::parse()).unwrap())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use assert_matches::assert_matches;
+    use rstest::*;
+    use tempfile::tempdir;
+
+    #[rstest]
+    // No device specified defaults to /dev/video0
+    #[case::no_device(vec!["", "-s", "video.sock", "-b", "null"],
+    VideoArgs {
+        socket_path: "video.sock".into(),
+        v4l2_device: "/dev/video0".into(),
+        backend: BackendType::Null,
+    })]
+    // Specifying device overwrite the default value
+    #[case::set_device(vec!["", "-s" , "video.sock", "-d", "/dev/video1", "-b", "null"],
+    VideoArgs {
+        socket_path: "video.sock".into(),
+        v4l2_device: "/dev/video1".into(),
+        backend: BackendType::Null,
+    })]
+    // Selecting different decoder
+    #[case::set_v4l2_decoder(vec![" ", "--socket-path", "long-video.sock", "-b", "v4l2-decoder"],
+    VideoArgs {
+        socket_path: "long-video.sock".into(),
+        v4l2_device: "/dev/video0".into(),
+        backend: BackendType::V4L2Decoder,
+    })]
+    fn test_command_line_arguments(#[case] args: Vec<&str>, #[case] command_line: VideoArgs) {
+        let args: VideoArgs = Parser::parse_from(args.as_slice());
+
+        assert_eq!(
+            VuVideoConfig::try_from(command_line).unwrap(),
+            VuVideoConfig::try_from(args).unwrap()
+        );
+    }
+
+    #[test]
+    fn test_fail_create_backend() {
+        use vhu_video::VuVideoError;
+        let config = VideoArgs {
+            socket_path: "video.sock".into(),
+            v4l2_device: "/path/invalid/video.dev".into(),
+            backend: BackendType::V4L2Decoder,
+        };
+        assert_matches!(
+            start_backend(VuVideoConfig::try_from(config.clone()).unwrap()).unwrap_err(),
+            Error::CouldNotCreateBackend(VuVideoError::AccessVideoDeviceFile)
+        );
+    }
+
+    #[test]
+    fn test_fail_listener() {
+        use std::fs::File;
+        let test_dir = tempdir().expect("Could not create a temp test directory.");
+        let v4l2_device = test_dir.path().join("video.dev");
+        File::create(&v4l2_device).expect("Could not create a test device file.");
+        let config = VideoArgs {
+            socket_path: "~/path/invalid/video.sock".into(),
+            v4l2_device: v4l2_device.to_owned(),
+            backend: BackendType::Null,
+        };
+        assert_matches!(
+            start_backend(VuVideoConfig::try_from(config).unwrap()).unwrap_err(),
+            Error::FailedCreatingListener(_)
+        );
+        // cleanup
+        std::fs::remove_file(v4l2_device).expect("Failed to clean up");
+        test_dir.close().unwrap();
+    }
+}

crates/video/src/stream.rs

@@ -375,3 +375,91 @@ impl Stream {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::vhu_video::tests::{test_dir, VideoDeviceMock};
+    use assert_matches::assert_matches;
+    use rstest::*;
+    use tempfile::TempDir;
+
+    const TEST_PLANES: [ResourcePlane; 1] = [ResourcePlane {
+        offset: 0,
+        address: 0x100,
+        length: 1024,
+    }];
+    const INVALID_MEM_TYPE: u32 = (MemoryType::VirtioObject as u32) + 1;
+    const INVALID_FORMAT: u32 = (Format::Fwht as u32) + 1;
+
+    #[rstest]
+    fn test_video_stream(test_dir: TempDir) {
+        let stream_id: u32 = 1;
+        let v4l2_device = VideoDeviceMock::new(&test_dir);
+        let resource_id: u32 = 1;
+        let mut stream = Stream::new(
+            stream_id,
+            Path::new(&v4l2_device.path),
+            MemoryType::GuestPages as u32,
+            MemoryType::VirtioObject as u32,
+            Format::Fwht as u32,
+        )
+        .expect("Failed to create stream");
+        assert_matches!(stream.memory(QueueType::InputQueue), MemoryType::GuestPages);
+        assert_matches!(
+            stream.memory(QueueType::OutputQueue),
+            MemoryType::VirtioObject
+        );
+
+        // Add resource
+        let planes_layout = 0;
+        let res = stream.add_resource(
+            resource_id,
+            planes_layout,
+            Vec::from(TEST_PLANES),
+            QueueType::InputQueue,
+        );
+        assert!(res.is_none());
+        // Resource is retrievable
+        let res = stream.find_resource_mut(resource_id, QueueType::InputQueue);
+        assert!(res.is_some());
+        let res = res.unwrap();
+        assert_eq!(res.planes_layout, planes_layout);
+        assert_eq!(res.queue_type, QueueType::InputQueue);
+        assert_eq!(res.state(), ResourceState::Created);
+        // Change resource state
+        res.set_queued();
+        assert!(stream.all_queued(QueueType::InputQueue));
+        // Clean resources
+        stream.empty_resources(QueueType::InputQueue);
+        assert!(stream.resources_mut(QueueType::InputQueue).is_empty());
+    }
+
+    #[rstest]
+    #[case::invalid_in_mem(
+        INVALID_MEM_TYPE, MemoryType::GuestPages as u32, Format::Fwht as u32)]
+    #[case::invalid_out_mem(
+        MemoryType::VirtioObject as u32, INVALID_MEM_TYPE, Format::Nv12 as u32)]
+    #[case::invalid_format(
+        MemoryType::VirtioObject as u32, MemoryType::VirtioObject as u32, INVALID_FORMAT)]
+    fn test_video_stream_failures(
+        test_dir: TempDir,
+        #[case] in_mem: u32,
+        #[case] out_mem: u32,
+        #[case] format: u32,
+    ) {
+        let stream_id: u32 = 1;
+        let v4l2_device = VideoDeviceMock::new(&test_dir);
+        assert_matches!(
+            Stream::new(
+                stream_id,
+                Path::new(&v4l2_device.path),
+                in_mem,
+                out_mem,
+                format
+            )
+            .unwrap_err(),
+            VuVideoError::VideoStreamCreate
+        );
+    }
+}

crates/video/src/vhu_video.rs

@@ -264,3 +264,121 @@ impl VhostUserBackendMut<VringRwLock, ()> for VuVideoBackend {
         self.exit_event.try_clone().ok()
     }
 }
+
+#[cfg(test)]
+pub mod tests {
+    use super::*;
+    use rstest::*;
+    use std::fs::File;
+    use std::path::PathBuf;
+    use tempfile::{tempdir, TempDir};
+    use vm_memory::GuestAddress;
+
+    pub struct VideoDeviceMock {
+        pub path: PathBuf,
+        _dev: File,
+    }
+
+    impl VideoDeviceMock {
+        pub fn new(test_dir: &TempDir) -> Self {
+            let v4l2_device = test_dir.path().join("video.dev");
+            Self {
+                path: v4l2_device.to_owned(),
+                _dev: File::create(v4l2_device.as_path())
+                    .expect("Could not create a test device file."),
+            }
+        }
+    }
+
+    impl Drop for VideoDeviceMock {
+        fn drop(&mut self) {
+            std::fs::remove_file(&self.path).expect("Failed to clean up test device file.");
+        }
+    }
+
+    fn setup_backend_memory(backend: &mut VuVideoBackend) -> [VringRwLock; 2] {
+        let mem = GuestMemoryAtomic::new(
+            GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap(),
+        );
+        let vrings = [
+            VringRwLock::new(mem.clone(), 0x1000).unwrap(),
+            VringRwLock::new(mem.clone(), 0x2000).unwrap(),
+        ];
+        vrings[0].set_queue_info(0x100, 0x200, 0x300).unwrap();
+        vrings[0].set_queue_ready(true);
+        vrings[1].set_queue_info(0x1100, 0x1200, 0x1300).unwrap();
+        vrings[1].set_queue_ready(true);
+
+        assert!(backend.update_memory(mem).is_ok());
+
+        vrings
+    }
+
+    /// Creates a new test dir. There is no need to clean it after, since Drop is implemented for TempDir.
+    #[fixture]
+    pub fn test_dir() -> TempDir {
+        tempdir().expect("Could not create a temp test directory.")
+    }
+
+    #[rstest]
+    fn test_video_backend(test_dir: TempDir) {
+        let v4l2_device = VideoDeviceMock::new(&test_dir);
+        let backend = VuVideoBackend::new(Path::new(&v4l2_device.path), BackendType::Null);
+
+        assert!(backend.is_ok());
+        let mut backend = backend.unwrap();
+
+        assert_eq!(backend.num_queues(), NUM_QUEUES);
+        assert_eq!(backend.max_queue_size(), QUEUE_SIZE);
+        assert_ne!(backend.features(), 0);
+        assert!(!backend.protocol_features().is_empty());
+        backend.set_event_idx(false);
+
+        let vrings = setup_backend_memory(&mut backend);
+
+        let config = backend.get_config(0, 4);
+        assert_eq!(config.len(), 4);
+        let version = u32::from_le_bytes(config.try_into().unwrap());
+        assert_eq!(version, 0);
+
+        let exit = backend.exit_event(0);
+        assert!(exit.is_some());
+        exit.unwrap().write(1).unwrap();
+        for queue in COMMAND_Q..VIDEO_EVENT {
+            // Skip exit event
+            if queue == NUM_QUEUES as u16 {
+                continue;
+            }
+            let ret = backend.handle_event(queue, EventSet::IN, &vrings, 0);
+            assert!(ret.is_ok());
+            assert!(!ret.unwrap());
+        }
+    }
+
+    #[rstest]
+    fn test_video_backend_failures(test_dir: TempDir) {
+        let v4l2_device = VideoDeviceMock::new(&test_dir);
+        let mut backend = VuVideoBackend::new(Path::new(&v4l2_device.path), BackendType::Null)
+            .expect("Could not create backend");
+        let vrings = setup_backend_memory(&mut backend);
+
+        // reading out of the config space, expecting empty config
+        let config = backend.get_config(44, 1);
+        assert_eq!(config.len(), 0);
+
+        assert_eq!(
+            backend
+                .handle_event(COMMAND_Q, EventSet::OUT, &vrings, 0)
+                .unwrap_err()
+                .to_string(),
+            VuVideoError::HandleEventNotEpollIn.to_string()
+        );
+        assert_eq!(
+            backend
+                .handle_event(VIDEO_EVENT + 1, EventSet::IN, &vrings, 0)
+                .unwrap_err()
+                .to_string(),
+            VuVideoError::HandleUnknownEvent.to_string()
+        );
+    }
+}