mcs/class/corlib/System.IO/CheckPermission.cs

   1 //------------------------------------------------------------------------------
   2 //
   3 // System.IO.CheckPermission.cs
   4 //
   5 // Copyright (C) 2001 Moonlight Enterprises, All Rights Reserved
   6 //
   7 // Author:         Jim Richardson, develop@wtfo-guru.com
   8 // Created:        Saturday, August 25, 2001
   9 //
  10 // NOTE: All contributors can freely add to this class or make modifications
  11 //       that do not break existing usage of methods
  12 //------------------------------------------------------------------------------
  13
  14 //
  15 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  16 //
  17 // Permission is hereby granted, free of charge, to any person obtaining
  18 // a copy of this software and associated documentation files (the
  19 // "Software"), to deal in the Software without restriction, including
  20 // without limitation the rights to use, copy, modify, merge, publish,
  21 // distribute, sublicense, and/or sell copies of the Software, and to
  22 // permit persons to whom the Software is furnished to do so, subject to
  23 // the following conditions:
  24 //
  25 // The above copyright notice and this permission notice shall be
  26 // included in all copies or substantial portions of the Software.
  27 //
  28 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  29 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  30 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  31 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  32 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  33 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  34 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  35 //
  36
  37
  38 using System;
  39 using System.Security;
  40 using System.Security.Permissions;
  41
  42 namespace System.IO
  43 {
  44         /// <summary>
  45         /// A utility class to assist with various permission validation in System.IO
  46         /// </summary>
  47         internal sealed class CheckPermission
  48         {
  49                 /// <summary>
  50                 /// Generates and exception if caller doesn't have flags access to filesystem item specified by path
  51                 /// </summary>
  52                 [MonoTODO]
  53                 public static void Demand(FileIOPermissionAccess flags, string path)
  54                 {
  55                         FileIOPermission ioPerm = new FileIOPermission(flags, path);
  56                         // FIXME: FileIOPermission is not yet implemented
  57                         //ioPerm.Demand();
  58                 }
  59
  60                 public static void Access(FileAccess access, string path)
  61                 {
  62                         switch(access)
  63                         {
  64                         case FileAccess.Read:
  65                                 Demand(FileIOPermissionAccess.Read, path);
  66                                 break;
  67                         case FileAccess.Write:
  68                                 Demand(FileIOPermissionAccess.Write, path);
  69                                 break;
  70                         case FileAccess.ReadWrite:
  71                                 Demand(FileIOPermissionAccess.Read | FileIOPermissionAccess.Write, path);
  72                                 break;
  73                         default:
  74                                 // TODO: determine what best to do here
  75                                 throw new ArgumentException("Invalid FileAccess parameter");
  76                         }
  77                 }
  78
  79                 [MonoTODO]
  80                 public static void ModeAccess(FileMode mode, FileAccess access, string path, bool exists)
  81                 {
  82 #if false
  83                         // TODO: this logic isn't entirely complete and accurate, yet
  84                         if((mode & (FileMode.CreateNew | FileMode.Create)) != 0)
  85                         {
  86                                 CheckPermission.Demand(FileIOPermissionAccess.Write, Path.GetDirectoryName(path));
  87                         }
  88                         else if((mode & FileMode.OpenOrCreate) != 0)
  89                         {
  90                                 if(!exists)
  91                                 {
  92                                         CheckPermission.Demand(FileIOPermissionAccess.Write, Path.GetDirectoryName(path));
  93                                 }
  94                                 else
  95                                 {
  96                                         CheckPermission.Access(access, path);
  97                                 }
  98                         }
  99                         else if(exists)
 100                         {
 101                                 CheckPermission.Access(access, path);
 102                         }
 103                         else
 104                         {
 105                                 throw new FileNotFoundException("File not found", path);
 106                         }
 107 #endif
 108                 }
 109         }
 110 }       // namespace System.IO.Private