Cleanup: private embedded types and readonly where appropriate (#187).

src/Microsoft.AspNet.Server.Kestrel/Http/FrameContext.cs

@@ -7,12 +7,10 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
     {
         public FrameContext()
         {
-
         }
 
         public FrameContext(ConnectionContext context) : base(context)
         {
-
         }
 
         public IFrameControl FrameControl { get; set; }

src/Microsoft.AspNet.Server.Kestrel/Http/FrameRequestHeaders.cs

@@ -21,11 +21,11 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
 
         public partial struct Enumerator : IEnumerator<KeyValuePair<string, StringValues>>
         {
-            private FrameRequestHeaders _collection;
+            private readonly FrameRequestHeaders _collection;
-            private long _bits;
+            private readonly long _bits;
             private int _state;
             private KeyValuePair<string, StringValues> _current;
-            private bool _hasUnknown;
+            private readonly bool _hasUnknown;
             private Dictionary<string, StringValues>.Enumerator _unknownEnumerator;
 
             internal Enumerator(FrameRequestHeaders collection)

src/Microsoft.AspNet.Server.Kestrel/Http/FrameResponseHeaders.cs

@@ -10,8 +10,8 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
 {
     public partial class FrameResponseHeaders : FrameHeaders
     {
-        private static byte[] _CrLf = new[] { (byte)'\r', (byte)'\n' };
+        private static readonly byte[] _CrLf = new[] { (byte)'\r', (byte)'\n' };
-        private static byte[] _colonSpace = new[] { (byte)':', (byte)' ' };
+        private static readonly byte[] _colonSpace = new[] { (byte)':', (byte)' ' };
 
         public bool HasConnection => HeaderConnection.Count != 0;
 
@@ -53,11 +53,11 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
 
         public partial struct Enumerator : IEnumerator<KeyValuePair<string, StringValues>>
         {
-            private FrameResponseHeaders _collection;
+            private readonly FrameResponseHeaders _collection;
-            private long _bits;
+            private readonly long _bits;
             private int _state;
             private KeyValuePair<string, StringValues> _current;
-            private bool _hasUnknown;
+            private readonly bool _hasUnknown;
             private Dictionary<string, StringValues>.Enumerator _unknownEnumerator;
 
             internal Enumerator(FrameResponseHeaders collection)

src/Microsoft.AspNet.Server.Kestrel/Http/Listener.cs

@@ -3,7 +3,6 @@
 
 using System;
 using System.Threading.Tasks;
-using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Networking;
 using Microsoft.Extensions.Logging;
 

src/Microsoft.AspNet.Server.Kestrel/Http/ListenerPrimary.cs

@@ -14,9 +14,9 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
     /// A primary listener waits for incoming connections on a specified socket. Incoming 
     /// connections may be passed to a secondary listener to handle.
     /// </summary>
-    abstract public class ListenerPrimary : Listener
+    public abstract class ListenerPrimary : Listener
     {
-        private List<UvPipeHandle> _dispatchPipes = new List<UvPipeHandle>();
+        private readonly List<UvPipeHandle> _dispatchPipes = new List<UvPipeHandle>();
         private int _dispatchIndex;
         private string _pipeName;
 
@@ -28,7 +28,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
         {
         }
 
-        UvPipeHandle ListenPipe { get; set; }
+        private UvPipeHandle ListenPipe { get; set; }
 
         public async Task StartAsync(
             string pipeName,

src/Microsoft.AspNet.Server.Kestrel/Http/MessageBody.cs

@@ -12,7 +12,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
 {
     public abstract class MessageBody
     {
-        private FrameContext _context;
+        private readonly FrameContext _context;
         private int _send100Continue = 1;
 
         protected MessageBody(FrameContext context)
@@ -130,7 +130,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
         }
 
 
-        class ForRemainingData : MessageBody
+        private class ForRemainingData : MessageBody
         {
             public ForRemainingData(FrameContext context)
                 : base(context)
@@ -143,7 +143,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
             }
         }
 
-        class ForContentLength : MessageBody
+        private class ForContentLength : MessageBody
         {
             private readonly int _contentLength;
             private int _inputLength;
@@ -182,7 +182,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
         /// <summary>
         ///   http://tools.ietf.org/html/rfc2616#section-3.6.1
         /// </summary>
-        class ForChunkedEncoding : MessageBody
+        private class ForChunkedEncoding : MessageBody
         {
             private int _inputLength;
 

src/Microsoft.AspNet.Server.Kestrel/Http/SocketOutput.cs

@@ -21,7 +21,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Http
         private const int _initialTaskQueues = 64;
         private const int _maxPooledWriteContexts = 32;
 
-        private static WaitCallback _returnBlocks = (state) => ReturnBlocks((MemoryPoolBlock2)state);
+        private static readonly WaitCallback _returnBlocks = (state) => ReturnBlocks((MemoryPoolBlock2)state);
 
         private readonly KestrelThread _thread;
         private readonly UvStreamHandle _socket;

src/Microsoft.AspNet.Server.Kestrel/Infrastructure/KestrelThread.cs

@@ -30,21 +30,21 @@ namespace Microsoft.AspNet.Server.Kestrel
         private static readonly Action<object, object> _listenerPrimaryCallbackAdapter = (callback, state) => ((Action<ListenerPrimary>)callback).Invoke((ListenerPrimary)state);
         private static readonly Action<object, object> _listenerSecondaryCallbackAdapter = (callback, state) => ((Action<ListenerSecondary>)callback).Invoke((ListenerSecondary)state);
 
-        private KestrelEngine _engine;
+        private readonly KestrelEngine _engine;
         private readonly IApplicationLifetime _appLifetime;
-        private Thread _thread;
+        private readonly Thread _thread;
-        private UvLoopHandle _loop;
+        private readonly UvLoopHandle _loop;
-        private UvAsyncHandle _post;
+        private readonly UvAsyncHandle _post;
         private Queue<Work> _workAdding = new Queue<Work>(1024);
         private Queue<Work> _workRunning = new Queue<Work>(1024);
         private Queue<CloseHandle> _closeHandleAdding = new Queue<CloseHandle>(256);
         private Queue<CloseHandle> _closeHandleRunning = new Queue<CloseHandle>(256);
-        private object _workSync = new Object();
+        private readonly object _workSync = new Object();
         private bool _stopImmediate = false;
         private bool _initCompleted = false;
         private ExceptionDispatchInfo _closeError;
-        private IKestrelTrace _log;
+        private readonly IKestrelTrace _log;
-        private IThreadPool _threadPool;
+        private readonly IThreadPool _threadPool;
 
         public KestrelThread(KestrelEngine engine)
         {

src/Microsoft.AspNet.Server.Kestrel/Infrastructure/KestrelTrace.cs

@@ -12,15 +12,15 @@ namespace Microsoft.AspNet.Server.Kestrel
     /// </summary>
     public class KestrelTrace : IKestrelTrace
     {
-        private static Action<ILogger, long, Exception> _connectionStart;
+        private static readonly Action<ILogger, long, Exception> _connectionStart;
-        private static Action<ILogger, long, Exception> _connectionStop;
+        private static readonly Action<ILogger, long, Exception> _connectionStop;
-        private static Action<ILogger, long, Exception> _connectionPause;
+        private static readonly Action<ILogger, long, Exception> _connectionPause;
-        private static Action<ILogger, long, Exception> _connectionResume;
+        private static readonly Action<ILogger, long, Exception> _connectionResume;
-        private static Action<ILogger, long, Exception> _connectionReadFin;
+        private static readonly Action<ILogger, long, Exception> _connectionReadFin;
-        private static Action<ILogger, long, Exception> _connectionWriteFin;
+        private static readonly Action<ILogger, long, Exception> _connectionWriteFin;
-        private static Action<ILogger, long, int, Exception> _connectionWroteFin;
+        private static readonly Action<ILogger, long, int, Exception> _connectionWroteFin;
-        private static Action<ILogger, long, Exception> _connectionKeepAlive;
+        private static readonly Action<ILogger, long, Exception> _connectionKeepAlive;
-        private static Action<ILogger, long, Exception> _connectionDisconnect;
+        private static readonly Action<ILogger, long, Exception> _connectionDisconnect;
 
         protected readonly ILogger _logger;
 

src/Microsoft.AspNet.Server.Kestrel/Infrastructure/MemoryPoolIterator2Extensions.cs

@@ -11,7 +11,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Infrastructure
     {
         private const int _maxStackAllocBytes = 16384;
 
-        private static Encoding _utf8 = Encoding.UTF8;
+        private static readonly Encoding _utf8 = Encoding.UTF8;
 
         public const string HttpConnectMethod = "CONNECT";
         public const string HttpDeleteMethod = "DELETE";
@@ -41,7 +41,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Infrastructure
         private readonly static long _http11VersionLong = GetAsciiStringAsLong("HTTP/1.1");
 
         private const int PerfectHashDivisor = 37;
-        private static Tuple<long, string>[] _knownStrings = new Tuple<long, string>[PerfectHashDivisor];
+        private static readonly Tuple<long, string>[] _knownStrings = new Tuple<long, string>[PerfectHashDivisor];
 
         static MemoryPoolIterator2Extensions()
         {

src/Microsoft.AspNet.Server.Kestrel/Networking/Libuv.cs

@@ -103,7 +103,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
             }
         }
 
-        public bool IsWindows;
+        public readonly bool IsWindows;
 
         public int Check(int statusCode)
         {

src/Microsoft.AspNet.Server.Kestrel/Networking/UvAsyncHandle.cs

@@ -8,7 +8,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
 {
     public class UvAsyncHandle : UvHandle
     {
-        private static Libuv.uv_async_cb _uv_async_cb = (handle) => AsyncCb(handle);
+        private static readonly Libuv.uv_async_cb _uv_async_cb = (handle) => AsyncCb(handle);
         private Action _callback;
 
         public UvAsyncHandle(IKestrelTrace logger) : base(logger)

src/Microsoft.AspNet.Server.Kestrel/Networking/UvHandle.cs

@@ -9,7 +9,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
 {
     public abstract class UvHandle : UvMemory
     {
-        private static Libuv.uv_close_cb _destroyMemory = (handle) => DestroyMemory(handle);
+        private static readonly Libuv.uv_close_cb _destroyMemory = (handle) => DestroyMemory(handle);
         private Action<Action<IntPtr>, IntPtr> _queueCloseHandle;
 
         protected UvHandle(IKestrelTrace logger) : base (logger)

src/Microsoft.AspNet.Server.Kestrel/Networking/UvMemory.cs

@@ -16,7 +16,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
     {
         protected Libuv _uv;
         protected int _threadId;
-        protected IKestrelTrace _log;
+        protected readonly IKestrelTrace _log;
 
         protected UvMemory(IKestrelTrace logger) : base(IntPtr.Zero, true)
         {

test/Microsoft.AspNet.Server.Kestrel.FunctionalTests/IPv6SupportedConditionAttribute.cs

@@ -11,7 +11,7 @@ namespace Microsoft.AspNet.Server.Kestrel.FunctionalTests
     [AttributeUsage(AttributeTargets.Method, AllowMultiple = false)]
     public class IPv6SupportedConditionAttribute : Attribute, ITestCondition
     {
-        private static Lazy<bool> _ipv6Supported = new Lazy<bool>(CanBindToIPv6Address);
+        private static readonly Lazy<bool> _ipv6Supported = new Lazy<bool>(CanBindToIPv6Address);
 
         public bool IsMet
         {