mcs/class/referencesource/System/net/System/Net/_WinHttpWebProxyDataBuilder.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.Text;
   4 using System.Runtime.InteropServices;
   5 using System.Runtime.CompilerServices;
   6
   7 namespace System.Net
   8 {
   9     internal sealed class WinHttpWebProxyBuilder : WebProxyDataBuilder
  10     {
  11         protected override void BuildInternal()
  12         {
  13             GlobalLog.Enter("WinHttpWebProxyBuilder#" + ValidationHelper.HashString(this) + "::BuildInternal()");
  14
  15             UnsafeNclNativeMethods.WinHttp.WINHTTP_CURRENT_USER_IE_PROXY_CONFIG ieProxyConfig =
  16                 new UnsafeNclNativeMethods.WinHttp.WINHTTP_CURRENT_USER_IE_PROXY_CONFIG();
  17
  18             // Make sure the native strings get freed, even if some unexpected exception occurs.
  19             RuntimeHelpers.PrepareConstrainedRegions();
  20             try
  21             {
  22                 if (UnsafeNclNativeMethods.WinHttp.WinHttpGetIEProxyConfigForCurrentUser(ref ieProxyConfig))
  23                 {
  24                     string proxy = null;
  25                     string proxyByPass = null;
  26                     string autoConfigUrl = null;
  27
  28                     proxy = Marshal.PtrToStringUni(ieProxyConfig.Proxy);
  29                     proxyByPass = Marshal.PtrToStringUni(ieProxyConfig.ProxyBypass);
  30                     autoConfigUrl = Marshal.PtrToStringUni(ieProxyConfig.AutoConfigUrl);
  31
  32                     // note that ieProxyConfig.Proxy will be null if "use a proxy server" flag is turned off, even if
  33                     // the user specified a proxy address. When we read directly from the Registry we need to check
  34                     // for ProxyTypeFlags.PROXY_TYPE_PROXY. WinHttp does this for us and if the flag is not set,
  35                     // ieProxyConfig.Proxy will be null.
  36                     SetProxyAndBypassList(proxy, proxyByPass);
  37
  38                     SetAutoDetectSettings(ieProxyConfig.AutoDetect);
  39
  40                     // similar to comment above: ieProxyConfig.AutoConfigUrl will only be set if "automatically detect
  41                     // settings" flag is set. We don't need to check ProxyTypeFlags.PROXY_TYPE_AUTO_PROXY_URL; WinHttp
  42                     // takes care of it and sets AutoConfigUrl to null if the flag is not set, regardless of the actual
  43                     // config script string.
  44                     SetAutoProxyUrl(autoConfigUrl);
  45                 }
  46                 else
  47                 {
  48                     int errorCode = Marshal.GetLastWin32Error();
  49
  50                     if (errorCode == Microsoft.Win32.NativeMethods.ERROR_NOT_ENOUGH_MEMORY)
  51                     {
  52                         throw new OutOfMemoryException();
  53                     }
  54
  55                     // if API call fails, rely on automatic detection
  56                     SetAutoDetectSettings(true);
  57                 }
  58             }
  59             finally
  60             {
  61                 Marshal.FreeHGlobal(ieProxyConfig.Proxy);
  62                 Marshal.FreeHGlobal(ieProxyConfig.ProxyBypass);
  63                 Marshal.FreeHGlobal(ieProxyConfig.AutoConfigUrl);
  64             }
  65
  66             GlobalLog.Leave("WinHttpWebProxyBuilder#" + ValidationHelper.HashString(this) + "::BuildInternal()");
  67         }
  68     }
  69 }