Fix SonarCloud code smells in Socket and SslStream

- SslStream
  + remove unnecessary boolean literals in Length/DataAvailable getters.
  + rename Read/Write parameter size → count to match Stream.
  + fix garbled Length/DataAvailable summaries and a typo.
- Socket
  + add XML doc to finalizer.
  + fix ambiguous Send/Receive cref references.
- Socket.ReceiveFrom: remove unreachable endpoint snapshot/store block; clarify comments.

Author: josesimoes

nanoFramework.System.Net/Security/SslStream.cs

@@ -325,27 +325,27 @@ internal void Authenticate(bool isServer, string targetHost, X509Certificate cer
         public bool IsServer { get { return _isServer; } }
 
         /// <summary>
-        /// Gets the length of the stream. (Overrides NetworkStream. . :: . .Length.)
+        /// Gets the number of bytes of decrypted data available to be read from the stream.
         /// </summary>
         public override long Length
         {
             get
             {
-                if (_disposed == true) throw new ObjectDisposedException();
+                if (_disposed) throw new ObjectDisposedException();
                 if (_socket == null) throw new IOException();
 
                 return SslNative.DataAvailable(_socket);
             }
         }
 
         /// <summary>
-        /// Gets a value the indicates whether data is available in the stream. (Overrides NetworkStream. . :: . .DataAvailable.)
+        /// Gets a value that indicates whether decrypted data is available on the stream to be read.
         /// </summary>
         public override bool DataAvailable
         {
             get
             {
-                if (_disposed == true) throw new ObjectDisposedException();
+                if (_disposed) throw new ObjectDisposedException();
                 if (_socket == null) throw new IOException();
 
                 return (SslNative.DataAvailable(_socket) > 0);
@@ -393,9 +393,9 @@ protected override void Dispose(bool disposing)
         /// </summary>
         /// <param name="buffer">An array that receives the bytes read from this stream.</param>
         /// <param name="offset">An integer that contains the zero-based location in buffer at which to begin storing the data read from this stream.</param>
-        /// <param name="size">The maximum number of bytes to read from this stream.</param>
+        /// <param name="count">The maximum number of bytes to read from this stream.</param>
         /// <returns></returns>
-        public override int Read(byte[] buffer, int offset, int size)
+        public override int Read(byte[] buffer, int offset, int count)
         {
             if (buffer == null)
             {
@@ -412,24 +412,24 @@ public override int Read(byte[] buffer, int offset, int size)
                 throw new ArgumentOutOfRangeException();
             }
 
-            if (size < 0 || size > buffer.Length - offset)
+            if (count < 0 || count > buffer.Length - offset)
             {
                 throw new ArgumentOutOfRangeException();
             }
 
-            return SslNative.SecureRead(_socket, buffer, offset, size, _socket.ReceiveTimeout);
+            return SslNative.SecureRead(_socket, buffer, offset, count, _socket.ReceiveTimeout);
         }
 
         /// <summary>
         /// Write the specified number of bytes to the underlying stream using the specified buffer and offset.
         /// </summary>
         /// <param name="buffer">An array that supplies the bytes written to the stream.</param>
-        /// <param name="offset">he zero-based location in buffer at which to begin reading bytes to be written to the stream.</param>
-        /// <param name="size">The number of bytes to read from buffer.</param>
+        /// <param name="offset">The zero-based location in buffer at which to begin reading bytes to be written to the stream.</param>
+        /// <param name="count">The number of bytes to read from buffer.</param>
         /// <exception cref="ArgumentNullException"><paramref name="buffer"/> is <see langword="null"/>.</exception>
         /// <exception cref="ArgumentOutOfRangeException">
         /// <para>
-        /// <paramref name="offset"/> or <paramref name="size"/> is less than zero
+        /// <paramref name="offset"/> or <paramref name="count"/> is less than zero
         /// </para>
         /// <para>
         /// -or-
@@ -441,15 +441,15 @@ public override int Read(byte[] buffer, int offset, int size)
         /// -or-
         /// </para>
         /// <para>
-        /// <paramref name="offset"/> + <paramref name="size"/> is greater than the length of <paramref name="buffer"/>.
+        /// <paramref name="offset"/> + <paramref name="count"/> is greater than the length of <paramref name="buffer"/>.
         /// </para>
         /// </exception>
         /// <exception cref="ObjectDisposedException">The stream has been disposed.</exception>
         /// <exception cref="IOException">The write operation failed.</exception>
         public override void Write(
             byte[] buffer,
             int offset,
-            int size)
+            int count)
         {
             if (buffer == null)
             {
@@ -466,14 +466,14 @@ public override void Write(
                 throw new ArgumentOutOfRangeException();
             }
 
-            if (size < 0 || size > buffer.Length - offset)
+            if (count < 0 || count > buffer.Length - offset)
             {
                 throw new ArgumentOutOfRangeException();
             }
 
-            int written = SslNative.SecureWrite(_socket, buffer, offset, size, _socket.SendTimeout);
+            int written = SslNative.SecureWrite(_socket, buffer, offset, count, _socket.SendTimeout);
 
-            if (written <= 0 && size > 0)
+            if (written <= 0 && count > 0)
             {
                 throw new IOException();
             }

nanoFramework.System.Net/Sockets/Socket.cs

@@ -181,7 +181,7 @@ public EndPoint RemoteEndPoint
         }
 
         /// <summary>
-        /// Gets a value that indicates whether a <see cref="Socket"/> is connected to a remote host as of the last <see cref="Send"/> or <see cref="Receive"/> operation.
+        /// Gets a value that indicates whether a <see cref="Socket"/> is connected to a remote host as of the last <see cref="Send(byte[])"/> or <see cref="Receive(byte[])"/> operation.
         /// </summary>
         /// <value>
         /// <see langword="true"/> if the <see cref="Socket"/> was connected to a remote resource as of the most recent operation; otherwise, <see langword="false"/>.
@@ -766,30 +766,12 @@ public int ReceiveFrom(byte[] buffer, int offset, int size, SocketFlags socketFl
 
             if (_rightEndPoint == null)
             {
-                // socket must have connection established or previously accepted a connection 
+                // socket must be bound (by Bind, Connect or SendTo)
                 throw new SocketException(SocketError.NotConnected);
             }
 
-            EndPoint endPointSnapshot = remoteEP;
-            Snapshot(ref endPointSnapshot);
-
-            int bytesTransferred = 0;
-
-            bytesTransferred = NativeSocket.recvfrom(this, buffer, offset, size, (int)socketFlags, m_recvTimeout, ref remoteEP);
-
-            if (!remoteEP.Equals(endPointSnapshot))
-            {
-                // no need to create a new EndPoint here if it's different from the orignal
-                // because the interpreter has already created a new instance of an IPEndPoint
-
-                if (_rightEndPoint == null)
-                {
-                    // save a copy of the EndPoint
-                    _rightEndPoint = remoteEP;
-                }
-            }
-
-            return bytesTransferred;
+            // recvfrom always replaces remoteEP with a new IPEndPoint holding the sender's address; the caller's instance is never modified
+            return NativeSocket.recvfrom(this, buffer, offset, size, (int)socketFlags, m_recvTimeout, ref remoteEP);
         }
 
         /// <summary>
@@ -1091,6 +1073,9 @@ void IDisposable.Dispose()
             GC.SuppressFinalize(this);
         }
 
+        /// <summary>
+        /// Releases unmanaged resources used by the <see cref="Socket"/> before it is reclaimed by garbage collection.
+        /// </summary>
         ~Socket()
         {
             Dispose(false);