Util/UnixListener.cs

   1 //
   2 // UnixListener.cs
   3 //
   4 // Authors:
   5 //      Joe Shaw (joeshaw@novell.com)
   6 //
   7 // Copyright (C) 2004-2005 Novell, Inc.
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining a
  12 // copy of this software and associated documentation files (the "Software"),
  13 // to deal in the Software without restriction, including without limitation
  14 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  15 // and/or sell copies of the Software, and to permit persons to whom the
  16 // Software is furnished to do so, subject to the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be included in
  19 // all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  26 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  27 // DEALINGS IN THE SOFTWARE.
  28 //
  29
  30
  31 using System;
  32 using System.Net;
  33 using System.Net.Sockets;
  34 using System.IO;
  35
  36 using Mono.Posix;
  37
  38 namespace Beagle.Util {
  39
  40         public class UnixListener : IDisposable {
  41                 bool disposed;
  42                 bool listening;
  43                 Socket server;
  44                 EndPoint savedEP;
  45
  46                 void Init (UnixEndPoint ep)
  47                 {
  48                         listening = false;
  49                         string filename = ep.Filename;
  50                         if (File.Exists (filename)) {
  51                                 Socket conn = new Socket (AddressFamily.Unix, SocketType.Stream, 0);
  52                                 try {
  53                                         conn.Connect (ep);
  54                                         conn.Close ();
  55                                         throw new InvalidOperationException ("There's already a server listening on " + filename);
  56                                 } catch (SocketException se) {
  57                                 }
  58                                 File.Delete (filename);
  59                         }
  60
  61                         server = new Socket (AddressFamily.Unix, SocketType.Stream, 0);
  62                         server.Bind (ep);
  63                         savedEP = server.LocalEndPoint;
  64                 }
  65
  66                 public UnixListener (string path)
  67                 {
  68                         if (!Directory.Exists (Path.GetDirectoryName (path)))
  69                                 Directory.CreateDirectory (Path.GetDirectoryName (path));
  70
  71                         Init (new UnixEndPoint (path));
  72                 }
  73
  74                 public UnixListener (UnixEndPoint localEndPoint)
  75                 {
  76                         if (localEndPoint == null)
  77                                 throw new ArgumentNullException ("localendPoint");
  78
  79                         Init (localEndPoint);
  80                 }
  81
  82                 public EndPoint LocalEndpoint {
  83                         get { return savedEP; }
  84                 }
  85
  86                 protected Socket Server {
  87                         get { return server; }
  88                 }
  89
  90                 public Socket AcceptSocket ()
  91                 {
  92                         CheckDisposed ();
  93                         if (!listening)
  94                                 throw new InvalidOperationException ("Socket is not listening");
  95
  96                         // FIXME: This is a hack to work around a mono bug.
  97                         // server.Accept() *should* throw a SocketException
  98                         // immediately if the listener's Stop() is called, but
  99                         // it doesn't.  So once that mono bug is fixed and
 100                         // reasonably deployed, we should remove the Poll()
 101                         // here and unconditionally return server.Accept().
 102                         //
 103                         // It is fixed in SVN post-1.1.7
 104
 105                         // Time out after one second
 106                         if (server.Poll (1000000, SelectMode.SelectRead)) // 1000000 microseconds = 1 second
 107                                 return server.Accept ();
 108                         else
 109                                 return null;
 110                 }
 111
 112                 public UnixClient AcceptUnixClient ()
 113                 {
 114                         CheckDisposed ();
 115                         if (!listening)
 116                                 throw new InvalidOperationException ("Socket is not listening");
 117
 118                         // FIXME: This is a hack to work around a mono bug.
 119                         // We shouldn't need to check for null, we should only
 120                         // need to "return new UnixClient (socket)".  Once the
 121                         // above FIXME is removed, fix this one too.
 122                         Socket socket = AcceptSocket ();
 123                         if (socket == null)
 124                                 return null;
 125                         return new UnixClient (socket);
 126                 }
 127
 128                 ~UnixListener ()
 129                 {
 130                         Dispose (false);
 131                 }
 132
 133                 public bool Pending ()
 134                 {
 135                         CheckDisposed ();
 136                         if (!listening)
 137                                 throw new InvalidOperationException ("Socket is not listening");
 138
 139                         return server.Poll (1000, SelectMode.SelectRead);
 140                 }
 141
 142                 public void Start ()
 143                 {
 144                         Start (5);
 145                 }
 146
 147                 public void Start (int backlog)
 148                 {
 149                         CheckDisposed ();
 150                         if (listening)
 151                                 return;
 152
 153                         server.Listen (backlog);
 154                         listening = true;
 155                 }
 156
 157                 public void Stop ()
 158                 {
 159                         CheckDisposed ();
 160                         Dispose (true);
 161                 }
 162
 163                 public void Dispose ()
 164                 {
 165                         Dispose (true);
 166                         GC.SuppressFinalize (this);
 167                 }
 168
 169                 protected void Dispose (bool disposing)
 170                 {
 171                         if (disposed)
 172                                 return;
 173
 174                         if (disposing) {
 175                                 if (server != null)
 176                                         server.Close ();
 177
 178                                 server = null;
 179                         }
 180
 181                         disposed = true;
 182                 }
 183
 184                 void CheckDisposed ()
 185                 {
 186                         if (disposed)
 187                                 throw new ObjectDisposedException (GetType().FullName);
 188                 }
 189         }
 190
 191 }