Support UTF8 filenames in FFmpeg reader

nativesrc/aurioffmpegproxy/proxy.c

@@ -671,7 +671,7 @@ static void pi_free(ProxyInstance **pi) {
 static void pi_set_error(ProxyInstance *pi, const char* fmt, ...)
 {
 	va_list args;
-	int error_message_length = 100;
+	int error_message_length = 500;
 	char *error_message = malloc(error_message_length);
 
 	// Print the string with the argument list into the error message char array

src/Aurio.FFmpeg.UnitTest/FFmpegReaderTests.cs

@@ -52,5 +52,13 @@ public void SignalEOF()
             // -1 signals EOF
             Assert.Equal(-1, result);
         }
+
+        [Fact]
+        public void Utf8FileName()
+        {
+            var fileInfo = new FileInfo("./Resources/utf8 special ° character.wav");
+
+            var reader = new FFmpegReader(fileInfo, Type.Audio);
+        }
     }
 }

src/Aurio.FFmpeg.UnitTest/Properties/launchSettings.json

@@ -0,0 +1,8 @@
+{
+  "profiles": {
+    "Aurio.FFmpeg.UnitTest": {
+      "commandName": "Project",
+      "nativeDebugging": true
+    }
+  }
+}

src/Aurio.FFmpeg/Aurio.FFmpeg.csproj

@@ -42,6 +42,9 @@
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
       <PackagePath>runtimes/win-x64/native</PackagePath>
     </Content>
+    <Content Include="$(FFmpegProxyWindowsPath)\aurioffmpegproxy.pdb" Condition="$(Configuration.Contains('Debug'))">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
   </ItemGroup>
   <ItemGroup Condition="$(Configuration.Contains('Linux')) Or $(Configuration.Contains('NugetPack'))">
     <Content Include="$(FFmpegProxyLinuxPath)\libaurioffmpegproxy.so">

src/Aurio.FFmpeg/FFmpegReader.cs

@@ -162,7 +162,7 @@ private void CheckAndHandleOpeningError()
         {
             if (InteropWrapper.stream_has_error(instance))
             {
-                string errorMessage = Marshal.PtrToStringAnsi(
+                string errorMessage = Marshal.PtrToStringUTF8(
                     InteropWrapper.stream_get_error(instance)
                 );
                 throw new IOException("Error opening the FFmpeg stream: " + errorMessage);

src/Aurio.FFmpeg/Interop64.cs

@@ -26,15 +26,18 @@ internal class Interop64
         private const string FFMPEGPROXYLIB = "aurioffmpegproxy";
 
         [DllImport(FFMPEGPROXYLIB, CallingConvention = InteropWrapper.CC)]
-        public static extern IntPtr stream_open_file(Type mode, string filename);
+        public static extern IntPtr stream_open_file(
+            Type mode,
+            [MarshalAs(UnmanagedType.LPUTF8Str)] string filename
+        );
 
         [DllImport(FFMPEGPROXYLIB, CallingConvention = InteropWrapper.CC)]
         public static extern IntPtr stream_open_bufferedio(
             Type mode,
             IntPtr opaque,
             InteropWrapper.CallbackDelegateReadPacket readPacket,
             InteropWrapper.CallbackDelegateSeek seek,
-            string filename
+            [MarshalAs(UnmanagedType.LPUTF8Str)] string filename
         );
 
         [DllImport(FFMPEGPROXYLIB, CallingConvention = InteropWrapper.CC)]

src/Aurio/Aurio.csproj

@@ -23,7 +23,7 @@ overlap-adding (OLA/COLA), fingerprinting, and WPF UI controls for visualization
     <PackageReference Include="NAudio.Core" Version="2.2.1" />
   </ItemGroup>
   <Target Name="PreBuild" BeforeTargets="PreBuildEvent">
-    <Exec Command="cp &quot;$(ProjectDir)/../../NOTICE&quot; &quot;$(ProjectDir)/licenseinfo.txt&quot;" />
+	<Copy SourceFiles="$(ProjectDir)..\..\NOTICE" DestinationFiles="$(ProjectDir)licenseinfo.txt" />
     <ItemGroup>
       <None Include="./README.nuget.md" Pack="true" PackagePath="/README.md" />
     </ItemGroup>