websocket-sharp/websocket-sharp/Net/ListenerPrefix.cs

//
// ListenerPrefix.cs
//	Copied from System.ListenerPrefix.cs
//
// Author:
//	Gonzalo Paniagua Javier (gonzalo@novell.com)
//	Oleg Mihailik (mihailik gmail co_m)
//
// Copyright (c) 2005 Novell, Inc. (http://www.novell.com)
// Copyright (c) 2012-2013 sta.blockhead
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Net;

namespace WebSocketSharp.Net
{
	internal sealed class ListenerPrefix
	{
		#region Private Fields

		IPAddress [] _addresses;
		string       _host;
		string       _original;
		string       _path;
		ushort       _port;
		bool         _secure;

		#endregion

		#region Public Fields

		public HttpListener Listener;

		#endregion

		#region Public Constructors

		// Must be called after calling ListenerPrefix.CheckUriPrefix.
		public ListenerPrefix (string uriPrefix)
		{
			_original = uriPrefix;
			parse (uriPrefix);
		}

		#endregion

		#region Public Properties

		public IPAddress [] Addresses {
			get {
				return _addresses;
			}

			set {
				_addresses = value;
			}
		}

		public string Host {
			get {
				return _host;
			}
		}

		public string Path {
			get {
				return _path;
			}
		}

		public int Port {
			get {
				return (int) _port;
			}
		}

		public bool Secure {
			get {
				return _secure;
			}
		}

		#endregion

		#region Private Methods

		private void parse (string uriPrefix)
		{
			int default_port = uriPrefix.StartsWith ("http://") ? 80 : 443;
			if (default_port == 443)
				_secure = true;

			int length = uriPrefix.Length;
			int start_host = uriPrefix.IndexOf (':') + 3;
			int colon = uriPrefix.IndexOf (':', start_host, length - start_host);
			int root;
			if (colon > 0)
			{
				root = uriPrefix.IndexOf ('/', colon, length - colon);
				_host = uriPrefix.Substring (start_host, colon - start_host);
				_port = (ushort) Int32.Parse (uriPrefix.Substring (colon + 1, root - colon - 1));
				_path = uriPrefix.Substring (root);
			}
			else
			{
				root = uriPrefix.IndexOf ('/', start_host, length - start_host);
				_host = uriPrefix.Substring (start_host, root - start_host);
				_port = (ushort) default_port;
				_path = uriPrefix.Substring (root);
			}

			if (_path.Length != 1)
				_path = _path.Substring (0, _path.Length - 1);
		}

		#endregion

		#region public Methods

		public static void CheckUriPrefix (string uriPrefix)
		{
			if (uriPrefix == null)
				throw new ArgumentNullException ("uriPrefix");

			int default_port = uriPrefix.StartsWith ("http://") ? 80 : -1;
			if (default_port == -1)
				default_port = uriPrefix.StartsWith ("https://") ? 443 : -1;

			if (default_port == -1)
				throw new ArgumentException ("Only 'http' and 'https' schemes are supported.");

			int length = uriPrefix.Length;
			int start_host = uriPrefix.IndexOf (':') + 3;
			if (start_host >= length)
				throw new ArgumentException ("No host specified.");

			int colon = uriPrefix.IndexOf (':', start_host, length - start_host);
			if (start_host == colon)
				throw new ArgumentException ("No host specified.");

			int root;
			if (colon > 0)
			{
				root = uriPrefix.IndexOf ('/', colon, length - colon);
				if (root == -1)
					throw new ArgumentException ("No path specified.");

				try {
					int port = Int32.Parse (uriPrefix.Substring (colon + 1, root - colon - 1));
					if (port <= 0 || port >= 65536)
						throw new Exception ();
				}
				catch {
					throw new ArgumentException ("Invalid port.");
				}
			}
			else
			{
				root = uriPrefix.IndexOf ('/', start_host, length - start_host);
				if (root == -1)
					throw new ArgumentException ("No path specified.");
			}

			if (uriPrefix [uriPrefix.Length - 1] != '/')
				throw new ArgumentException ("The URI prefix must end with '/'.");
		}

		// Equals and GetHashCode are required to detect duplicates in HttpListenerPrefixCollection.
		public override bool Equals (object obj)
		{
			var other = obj as ListenerPrefix;
			if (other == null)
				return false;

			return _original == other._original;
		}

		public override int GetHashCode ()
		{
			return _original.GetHashCode ();
		}

		public override string ToString ()
		{
			return _original;
		}

		#endregion
	}
}