mcs/class/corlib/System.Security.Permissions/FileDialogPermission.cs

   1 //
   2 // System.Security.Permissions.FileDialogPermission.cs
   3 //
   4 // Author
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2003 Motus Technologies. http://www.motus.com
   8 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Runtime.InteropServices;
  31 \r
  32 namespace System.Security.Permissions {\r
  33 \r
  34 #if NET_2_0
  35         [ComVisible (true)]
  36 #endif
  37         [Serializable]
  38         public sealed class FileDialogPermission : CodeAccessPermission, IUnrestrictedPermission, IBuiltInPermission {
  39
  40                 private const int version = 1;
  41
  42                 private FileDialogPermissionAccess _access;
  43
  44                 // Constructors
  45
  46                 public FileDialogPermission (PermissionState state)
  47                 {
  48                         if (CheckPermissionState (state, true) == PermissionState.Unrestricted)
  49                                 _access = FileDialogPermissionAccess.OpenSave;
  50                         else
  51                                 _access = FileDialogPermissionAccess.None;
  52                 }
  53
  54                 public FileDialogPermission (FileDialogPermissionAccess access)
  55                 {
  56                         // reuse validation by the Flags property
  57                         Access = access;
  58                 }
  59
  60                 // Properties
  61
  62                 public FileDialogPermissionAccess Access {
  63                         get { return _access; }
  64                         set {
  65                                 if (!Enum.IsDefined (typeof (FileDialogPermissionAccess), value)) {
  66                                         string msg = String.Format (Locale.GetText ("Invalid enum {0}"), value);
  67                                         throw new ArgumentException (msg, "FileDialogPermissionAccess");
  68                                 }
  69                                 _access = value;
  70                         }
  71                 }
  72
  73                 // Methods
  74
  75                 public override IPermission Copy ()
  76                 {
  77                         return new FileDialogPermission (_access);
  78                 }
  79
  80                 public override void FromXml (SecurityElement esd)
  81                 {
  82                         // General validation in CodeAccessPermission
  83                         CheckSecurityElement (esd, "esd", version, version);
  84                         // Note: we do not (yet) care about the return value
  85                         // as we only accept version 1 (min/max values)
  86
  87                         if (IsUnrestricted (esd)) {
  88                                 _access = FileDialogPermissionAccess.OpenSave;
  89                         }
  90                         else {
  91                                 string a = esd.Attribute ("Access");
  92                                 if (a == null)
  93                                         _access = FileDialogPermissionAccess.None;
  94                                 else {
  95                                         _access = (FileDialogPermissionAccess) Enum.Parse (
  96                                                 typeof (FileDialogPermissionAccess), a);
  97                                 }
  98                         }
  99                 }
 100
 101                 public override IPermission Intersect (IPermission target)
 102                 {
 103                         FileDialogPermission fdp = Cast (target);
 104                         if (fdp == null)
 105                                 return null;
 106
 107                         FileDialogPermissionAccess a = (_access & fdp._access);
 108                         return ((a == FileDialogPermissionAccess.None) ? null : new FileDialogPermission (a));
 109                 }
 110
 111                 public override bool IsSubsetOf (IPermission target)
 112                 {
 113                         FileDialogPermission fdp = Cast (target);
 114                         if (fdp == null)
 115                                 return false;
 116
 117                         return ((_access & fdp._access) == _access);
 118                 }
 119
 120                 public bool IsUnrestricted ()
 121                 {
 122                         return (_access == FileDialogPermissionAccess.OpenSave);
 123                 }
 124
 125 #if !NET_2_0
 126                 // Same results as base class - so why is it overrided ?
 127                 public override string ToString ()
 128                 {
 129                         return base.ToString ();
 130                 }
 131 #endif
 132
 133                 public override SecurityElement ToXml ()
 134                 {
 135                         SecurityElement se = Element (1);
 136                         switch (_access) {
 137                                 case FileDialogPermissionAccess.Open:
 138                                         se.AddAttribute ("Access", "Open");
 139                                         break;
 140                                 case FileDialogPermissionAccess.Save:
 141                                         se.AddAttribute ("Access", "Save");
 142                                         break;
 143                                 case FileDialogPermissionAccess.OpenSave:
 144                                         se.AddAttribute ("Unrestricted", "true");
 145                                         break;
 146                         }
 147                         return se;
 148                 }
 149
 150                 public override IPermission Union (IPermission target)
 151                 {
 152                         FileDialogPermission fdp = Cast (target);
 153                         if (fdp == null)
 154                                 return Copy ();
 155
 156                         if (IsUnrestricted () || fdp.IsUnrestricted ())
 157                                 return new FileDialogPermission (PermissionState.Unrestricted);
 158
 159                         return new FileDialogPermission (_access | fdp._access);
 160                 }
 161
 162                 // IBuiltInPermission
 163                 int IBuiltInPermission.GetTokenIndex ()
 164                 {
 165                         return (int) BuiltInToken.FileDialog;
 166                 }
 167
 168                 // helpers
 169
 170                 private FileDialogPermission Cast (IPermission target)
 171                 {
 172                         if (target == null)
 173                                 return null;
 174
 175                         FileDialogPermission fdp = (target as FileDialogPermission);
 176                         if (fdp == null) {
 177                                 ThrowInvalidPermission (target, typeof (FileDialogPermission));
 178                         }
 179
 180                         return fdp;
 181                 }
 182         }
 183 }