Merge pull request #6 from YimingZhanshen/copilot/add-screen-mirror-detection

Auto-launch ffplay on mirroring, fix reconnection port leak, fix audio seq wraparound, optimize CI

Author: YimingZhanshen

.github/workflows/build.yml

@@ -31,18 +31,40 @@ jobs:
     - name: Publish
       run: dotnet publish AirPlay/AirPlay.csproj --configuration Release --runtime win-x64 --self-contained true --output ./publish/win-x64
 
+    - name: Cache FFmpeg
+      id: cache-ffmpeg
+      uses: actions/cache@v4
+      with:
+        path: ffmpeg-cache
+        key: ffmpeg-win64-gpl-v1
+
     - name: Download FFmpeg
+      if: steps.cache-ffmpeg.outputs.cache-hit != 'true'
       shell: pwsh
       run: |
         $ffmpegUrl = "https://github.com/BtbN/FFmpeg-Builds/releases/download/latest/ffmpeg-master-latest-win64-gpl.zip"
         Invoke-WebRequest -Uri $ffmpegUrl -OutFile ffmpeg.zip
         Expand-Archive -Path ffmpeg.zip -DestinationPath ffmpeg-tmp
-        # Copy ffmpeg.exe and ffplay.exe to publish directory
         $binDir = Get-ChildItem -Path ffmpeg-tmp -Recurse -Directory -Filter "bin" | Select-Object -First 1
-        Copy-Item "$($binDir.FullName)\ffmpeg.exe" -Destination ./publish/win-x64/
-        Copy-Item "$($binDir.FullName)\ffplay.exe" -Destination ./publish/win-x64/
+        New-Item -ItemType Directory -Force -Path ffmpeg-cache
+        Copy-Item "$($binDir.FullName)\ffmpeg.exe" -Destination ffmpeg-cache/
+        Copy-Item "$($binDir.FullName)\ffplay.exe" -Destination ffmpeg-cache/
+
+    - name: Copy FFmpeg to publish
+      shell: pwsh
+      run: |
+        Copy-Item "ffmpeg-cache\ffmpeg.exe" -Destination ./publish/win-x64/
+        Copy-Item "ffmpeg-cache\ffplay.exe" -Destination ./publish/win-x64/
+
+    - name: Cache libfdk-aac
+      id: cache-fdkaac
+      uses: actions/cache@v4
+      with:
+        path: fdkaac-cache
+        key: fdkaac-win64-v1
 
     - name: Build libfdk-aac from source
+      if: steps.cache-fdkaac.outputs.cache-hit != 'true'
       shell: bash
       run: |
         # Build FDK-AAC from official source using MSYS2 (pre-installed on windows-latest)
@@ -61,16 +83,21 @@ jobs:
         cmake -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=ON ..
         cmake --build . --config Release
 
-        # Find and copy the DLL
+        # Find and copy the DLL to cache
         echo "Built files:"
         find . -name "*.dll" -type f
         DLL_PATH=$(find . -name "fdk-aac*.dll" -o -name "libfdk-aac*.dll" | head -1)
         if [ -z "$DLL_PATH" ]; then
           echo "ERROR: No FDK-AAC DLL found after build"
           exit 1
         fi
-        cp -v "$DLL_PATH" ../../publish/win-x64/libfdk-aac-2.dll
-        echo "Successfully built and copied libfdk-aac-2.dll"
+        mkdir -p ../../fdkaac-cache
+        cp -v "$DLL_PATH" ../../fdkaac-cache/libfdk-aac-2.dll
+        echo "Successfully built and cached libfdk-aac-2.dll"
+
+    - name: Copy libfdk-aac to publish
+      shell: bash
+      run: cp -v fdkaac-cache/libfdk-aac-2.dll publish/win-x64/libfdk-aac-2.dll
 
     - name: Upload build artifacts
       uses: actions/upload-artifact@v4

AirPlay/AirPlayReceiver.cs

@@ -19,6 +19,8 @@ public class AirPlayReceiver : IRtspReceiver, IAirPlayReceiver, IDisposable
         public event EventHandler<H264Data> OnH264DataReceived;
         public event EventHandler<PcmData> OnPCMDataReceived;
         public event EventHandler OnAudioFlushReceived;
+        public event EventHandler OnMirroringStartedReceived;
+        public event EventHandler OnMirroringStoppedReceived;
 
         public const string AirPlayType = "_airplay._tcp";
         public const string AirTunesType = "_raop._tcp";
@@ -147,6 +149,16 @@ public void OnAudioFlush()
             OnAudioFlushReceived?.Invoke(this, EventArgs.Empty);
         }
 
+        public void OnMirroringStarted()
+        {
+            OnMirroringStartedReceived?.Invoke(this, EventArgs.Empty);
+        }
+
+        public void OnMirroringStopped()
+        {
+            OnMirroringStoppedReceived?.Invoke(this, EventArgs.Empty);
+        }
+
         public void Dispose()
         {
             _mdns?.Stop();

AirPlay/AirPlayService.cs

@@ -96,18 +96,9 @@ public async Task StartAsync(CancellationToken cancellationToken)
                 }
             }
 
-            // Initialize video output (named pipe for external player)
-            try
-            {
-                _videoOutput = new VideoOutputService();
-                _videoOutput.Initialize();
-                Console.WriteLine("Video output initialized successfully");
-            }
-            catch (Exception ex)
-            {
-                Console.WriteLine($"Failed to initialize video output: {ex.Message}");
-                Console.WriteLine("Continuing without video output...");
-            }
+            // Initialize video output service (will be started/stopped per mirroring session)
+            _videoOutput = new VideoOutputService();
+            Console.WriteLine("Video output service ready (will auto-launch ffplay when mirroring starts)");
 
             await _airPlayReceiver.StartListeners(cancellationToken);
             await _airPlayReceiver.StartMdnsAsync().ConfigureAwait(false);
@@ -129,6 +120,24 @@ public async Task StartAsync(CancellationToken cancellationToken)
                 }
             };
 
+            _airPlayReceiver.OnMirroringStartedReceived += (s, e) =>
+            {
+                Console.WriteLine("Mirroring started - launching video player...");
+                lock (_videoOutputLock)
+                {
+                    _videoOutput?.StartMirroring();
+                }
+            };
+
+            _airPlayReceiver.OnMirroringStoppedReceived += (s, e) =>
+            {
+                Console.WriteLine("Mirroring stopped - closing video player...");
+                lock (_videoOutputLock)
+                {
+                    _videoOutput?.StopMirroring();
+                }
+            };
+
             // H264 VIDEO OUTPUT
             _airPlayReceiver.OnH264DataReceived += (s, e) =>
             {

AirPlay/IAirPlayReceiver.cs

@@ -11,6 +11,8 @@ public interface IAirPlayReceiver
         event EventHandler<H264Data> OnH264DataReceived;
         event EventHandler<PcmData> OnPCMDataReceived;
         event EventHandler OnAudioFlushReceived;
+        event EventHandler OnMirroringStartedReceived;
+        event EventHandler OnMirroringStoppedReceived;
 
         Task StartListeners(CancellationToken cancellationToken);
 

AirPlay/IRtspReceiver.cs

@@ -11,5 +11,7 @@ public interface IRtspReceiver
         void OnData(H264Data data);
         void OnPCMData(PcmData data);
         void OnAudioFlush();
+        void OnMirroringStarted();
+        void OnMirroringStopped();
     }
 }

AirPlay/Listeners/AirTunesListener.cs

@@ -450,6 +450,7 @@ public override async Task OnDataReceivedAsync(Request request, Response respons
                             await mirroring.StartAsync(cancellationToken).ConfigureAwait(false);
 
                             session.MirroringListener = mirroring;
+                            _receiver.OnMirroringStarted();
                         }
                         if (session.FairPlayReady && (!session.MirroringSession.HasValue || !session.MirroringSession.Value))
                         {
@@ -612,6 +613,7 @@ public override async Task OnDataReceivedAsync(Request request, Response respons
                             session.SpsPps = null;
                             session.StreamConnectionId = null;
                             session.MirroringSession = null;
+                            _receiver.OnMirroringStopped();
                         }
                         // If audio session
                         if (type == 96)

AirPlay/Listeners/AudioListener.cs

@@ -444,16 +444,17 @@ public int RaopBufferQueue(RaopBuffer raop_buffer, byte[] data, ushort datalen,
             if (_queueCallCount <= 10 || _queueCallCount % 500 == 0)
                 Console.WriteLine($"[DEBUG-QUEUE] #{_queueCallCount}: seqnum={seqnum}, datalen={datalen}, payloadSize={datalen - 12}, bufferEmpty={raop_buffer.IsEmpty}, firstSeq={raop_buffer.FirstSeqNum}, lastSeq={raop_buffer.LastSeqNum}");
 
-            // Ignore, old
-            if (!raop_buffer.IsEmpty && seqnum < raop_buffer.FirstSeqNum && seqnum != 0)
+            // Ignore, old (use wraparound-aware comparison for 16-bit sequence numbers)
+            if (!raop_buffer.IsEmpty && SeqBefore(seqnum, raop_buffer.FirstSeqNum))
             {
                 if (_queueCallCount <= 10)
                     Console.WriteLine($"[DEBUG-QUEUE] #{_queueCallCount}: SKIP old seqnum={seqnum} < firstSeqNum={raop_buffer.FirstSeqNum}");
                 return 0;
             }
 
             /* Check that there is always space in the buffer, otherwise flush */
-            if (raop_buffer.FirstSeqNum + RAOP_BUFFER_LENGTH < seqnum || seqnum == 0)
+            /* Use wraparound-aware gap detection: if seqnum is more than RAOP_BUFFER_LENGTH ahead of FirstSeqNum, flush */
+            if (!raop_buffer.IsEmpty && (ushort)(seqnum - raop_buffer.FirstSeqNum) >= RAOP_BUFFER_LENGTH)
             {
                 RaopBufferFlush(raop_buffer, seqnum);
             }
@@ -543,7 +544,7 @@ public int RaopBufferQueue(RaopBuffer raop_buffer, byte[] data, ushort datalen,
                 raop_buffer.IsEmpty = false;
             }
 
-            if (raop_buffer.LastSeqNum < seqnum)
+            if (SeqBefore(raop_buffer.LastSeqNum, seqnum))
             {
                 raop_buffer.LastSeqNum = seqnum;
             }
@@ -686,6 +687,16 @@ private int RaopRtpResendCallback(Socket cSocket, ushort control_seqnum, ushort
             return 0;
         }
 
+        /// <summary>
+        /// Wraparound-aware comparison for 16-bit sequence numbers.
+        /// Returns true if s1 is strictly before s2 in the circular sequence space.
+        /// When (s1 - s2) interpreted as signed 16-bit is negative, s1 is before s2.
+        /// </summary>
+        private static bool SeqBefore(ushort s1, ushort s2)
+        {
+            return ((short)(s1 - s2)) < 0;
+        }
+
         private void InitializeDecoder (Session session)
         {
             lock (_decoderLock)

AirPlay/Listeners/Bases/BaseTcpListener.cs

@@ -42,6 +42,7 @@ public override Task StartAsync(CancellationToken cancellationToken)
         public override Task StopAsync()
         {
             _cancellationTokenSource.Cancel();
+            try { _listener.Stop(); } catch { }
             return Task.CompletedTask;
         }
 
@@ -59,17 +60,23 @@ private async Task AcceptClientsAsync(CancellationToken cancellationToken)
         {
             _listener.Start();
 
-            while (!cancellationToken.IsCancellationRequested)
+            try
             {
-                var client = await _listener.AcceptTcpClientAsync().ConfigureAwait(false);
-                var task = HandleClientAsync(client, cancellationToken);
-
-                var remoteEndpoint = client.Client.RemoteEndPoint.ToString();
-                if (!_connections.TryAdd(remoteEndpoint, task))
+                while (!cancellationToken.IsCancellationRequested)
                 {
-                    client.Close();
+                    var client = await _listener.AcceptTcpClientAsync().ConfigureAwait(false);
+                    var task = HandleClientAsync(client, cancellationToken);
+
+                    var remoteEndpoint = client.Client.RemoteEndPoint.ToString();
+                    if (!_connections.TryAdd(remoteEndpoint, task))
+                    {
+                        client.Close();
+                    }
                 }
             }
+            catch (ObjectDisposedException) { }
+            catch (InvalidOperationException) { }
+            catch (System.Net.Sockets.SocketException) { }
         }
 
         private async Task HandleClientAsync(TcpClient client, CancellationToken cancellationToken)