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         [ComVisible (true)]
  35         [Serializable]
  36         public sealed class FileDialogPermission : CodeAccessPermission, IUnrestrictedPermission, IBuiltInPermission {
  37
  38                 private const int version = 1;
  39
  40                 private FileDialogPermissionAccess _access;
  41
  42                 // Constructors
  43
  44                 public FileDialogPermission (PermissionState state)
  45                 {
  46                         if (CheckPermissionState (state, true) == PermissionState.Unrestricted)
  47                                 _access = FileDialogPermissionAccess.OpenSave;
  48                         else
  49                                 _access = FileDialogPermissionAccess.None;
  50                 }
  51
  52                 public FileDialogPermission (FileDialogPermissionAccess access)
  53                 {
  54                         // reuse validation by the Flags property
  55                         Access = access;
  56                 }
  57
  58                 // Properties
  59
  60                 public FileDialogPermissionAccess Access {
  61                         get { return _access; }
  62                         set {
  63                                 if (!Enum.IsDefined (typeof (FileDialogPermissionAccess), value)) {
  64                                         string msg = String.Format (Locale.GetText ("Invalid enum {0}"), value);
  65                                         throw new ArgumentException (msg, "FileDialogPermissionAccess");
  66                                 }
  67                                 _access = value;
  68                         }
  69                 }
  70
  71                 // Methods
  72
  73                 public override IPermission Copy ()
  74                 {
  75                         return new FileDialogPermission (_access);
  76                 }
  77
  78                 public override void FromXml (SecurityElement esd)
  79                 {
  80                         // General validation in CodeAccessPermission
  81                         CheckSecurityElement (esd, "esd", version, version);
  82                         // Note: we do not (yet) care about the return value
  83                         // as we only accept version 1 (min/max values)
  84
  85                         if (IsUnrestricted (esd)) {
  86                                 _access = FileDialogPermissionAccess.OpenSave;
  87                         }
  88                         else {
  89                                 string a = esd.Attribute ("Access");
  90                                 if (a == null)
  91                                         _access = FileDialogPermissionAccess.None;
  92                                 else {
  93                                         _access = (FileDialogPermissionAccess) Enum.Parse (
  94                                                 typeof (FileDialogPermissionAccess), a);
  95                                 }
  96                         }
  97                 }
  98
  99                 public override IPermission Intersect (IPermission target)
 100                 {
 101                         FileDialogPermission fdp = Cast (target);
 102                         if (fdp == null)
 103                                 return null;
 104
 105                         FileDialogPermissionAccess a = (_access & fdp._access);
 106                         return ((a == FileDialogPermissionAccess.None) ? null : new FileDialogPermission (a));
 107                 }
 108
 109                 public override bool IsSubsetOf (IPermission target)
 110                 {
 111                         FileDialogPermission fdp = Cast (target);
 112                         if (fdp == null)
 113                                 return false;
 114
 115                         return ((_access & fdp._access) == _access);
 116                 }
 117
 118                 public bool IsUnrestricted ()
 119                 {
 120                         return (_access == FileDialogPermissionAccess.OpenSave);
 121                 }
 122
 123                 public override SecurityElement ToXml ()
 124                 {
 125                         SecurityElement se = Element (1);
 126                         switch (_access) {
 127                                 case FileDialogPermissionAccess.Open:
 128                                         se.AddAttribute ("Access", "Open");
 129                                         break;
 130                                 case FileDialogPermissionAccess.Save:
 131                                         se.AddAttribute ("Access", "Save");
 132                                         break;
 133                                 case FileDialogPermissionAccess.OpenSave:
 134                                         se.AddAttribute ("Unrestricted", "true");
 135                                         break;
 136                         }
 137                         return se;
 138                 }
 139
 140                 public override IPermission Union (IPermission target)
 141                 {
 142                         FileDialogPermission fdp = Cast (target);
 143                         if (fdp == null)
 144                                 return Copy ();
 145
 146                         if (IsUnrestricted () || fdp.IsUnrestricted ())
 147                                 return new FileDialogPermission (PermissionState.Unrestricted);
 148
 149                         return new FileDialogPermission (_access | fdp._access);
 150                 }
 151
 152                 // IBuiltInPermission
 153                 int IBuiltInPermission.GetTokenIndex ()
 154                 {
 155                         return (int) BuiltInToken.FileDialog;
 156                 }
 157
 158                 // helpers
 159
 160                 private FileDialogPermission Cast (IPermission target)
 161                 {
 162                         if (target == null)
 163                                 return null;
 164
 165                         FileDialogPermission fdp = (target as FileDialogPermission);
 166                         if (fdp == null) {
 167                                 ThrowInvalidPermission (target, typeof (FileDialogPermission));
 168                         }
 169
 170                         return fdp;
 171                 }
 172         }
 173 }