mcs/class/System/System.Net/GlobalProxySelection.cs

   1 //
   2 // System.Net.GlobalProxySelection
   3 //
   4 // Author:
   5 //   Lawrence Pit (loz@cable.a2000.nl)
   6 //
   7
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Collections;
  31 using System.Configuration;
  32 using System.IO;
  33 using System.Runtime.Serialization;
  34
  35 namespace System.Net
  36 {
  37         public class GlobalProxySelection
  38         {
  39                 private static IWebProxy proxy;
  40
  41                 // Constructors
  42                 public GlobalProxySelection() { }
  43
  44                 // Properties
  45
  46                 static IWebProxy GetProxy ()
  47                 {
  48                         if (proxy != null)
  49                                 return proxy;
  50
  51                         lock (typeof (GlobalProxySelection)) {
  52                                 if (proxy != null)
  53                                         return proxy;
  54
  55                                 object p = ConfigurationSettings.GetConfig ("system.net/defaultProxy");
  56                                 if (p == null)
  57                                         p = new EmptyWebProxy ();
  58
  59                                 proxy = (IWebProxy) p;
  60                         }
  61
  62                         return proxy;
  63                 }
  64
  65                 public static IWebProxy Select {
  66                         get { return GetProxy (); }
  67                         set {
  68                                 if (value == null)
  69                                         throw new ArgumentNullException ("GlobalProxySelection.Select",
  70                                                         "null IWebProxy not allowed. Use GetEmptyWebProxy ()");
  71
  72                                 lock (typeof (GlobalProxySelection))
  73                                         proxy = value;
  74                         }
  75                 }
  76
  77                 // Methods
  78
  79                 public static IWebProxy GetEmptyWebProxy()
  80                 {
  81                         // must return a new one each time, as the credentials
  82                         // can be set
  83                         return new EmptyWebProxy ();
  84                 }
  85
  86                 // Internal Classes
  87
  88                 internal class EmptyWebProxy : IWebProxy {
  89                         private ICredentials credentials = null;
  90
  91                         internal EmptyWebProxy () { }
  92
  93                         public ICredentials Credentials {
  94                                 get { return credentials; }
  95                                 set { credentials = value; }
  96                         }
  97
  98                         public Uri GetProxy (Uri destination)
  99                         {
 100                                 return destination;
 101                         }
 102
 103                         public bool IsBypassed (Uri host)
 104                         {
 105                                 return true; // pass directly to host
 106                         }
 107                 }
 108         }
 109 }