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 using System;
  16 using System.Security;
  17 using System.Security.Permissions;
  18
  19 namespace System.IO
  20 {
  21         /// <summary>
  22         /// A utility class to assist with various permission validation in System.IO
  23         /// </summary>
  24         internal sealed class CheckPermission
  25         {
  26                 /// <summary>
  27                 /// Generates and exception if caller doesn't have flags access to filesystem item specified by path
  28                 /// </summary>
  29                 [MonoTODO]
  30                 public static void Demand(FileIOPermissionAccess flags, string path)
  31                 {
  32                         FileIOPermission ioPerm = new FileIOPermission(flags, path);
  33                         // FIXME: FileIOPermission is not yet implemented
  34                         //ioPerm.Demand();
  35                 }
  36
  37                 public static void Access(FileAccess access, string path)
  38                 {
  39                         switch(access)
  40                         {
  41                         case FileAccess.Read:
  42                                 Demand(FileIOPermissionAccess.Read, path);
  43                                 break;
  44                         case FileAccess.Write:
  45                                 Demand(FileIOPermissionAccess.Write, path);
  46                                 break;
  47                         case FileAccess.ReadWrite:
  48                                 Demand(FileIOPermissionAccess.Read | FileIOPermissionAccess.Write, path);
  49                                 break;
  50                         default:
  51                                 // TODO: determine what best to do here
  52                                 throw new ArgumentException("Invalid FileAccess parameter");
  53                         }
  54                 }
  55
  56                 [MonoTODO]
  57                 public static void ModeAccess(FileMode mode, FileAccess access, string path, bool exists)
  58                 {
  59 #if false
  60                         // TODO: this logic isn't entirely complete and accurate, yet
  61                         if((mode & (FileMode.CreateNew | FileMode.Create)) != 0)
  62                         {
  63                                 CheckPermission.Demand(FileIOPermissionAccess.Write, Path.GetDirectoryName(path));
  64                         }
  65                         else if((mode & FileMode.OpenOrCreate) != 0)
  66                         {
  67                                 if(!exists)
  68                                 {
  69                                         CheckPermission.Demand(FileIOPermissionAccess.Write, Path.GetDirectoryName(path));
  70                                 }
  71                                 else
  72                                 {
  73                                         CheckPermission.Access(access, path);
  74                                 }
  75                         }
  76                         else if(exists)
  77                         {
  78                                 CheckPermission.Access(access, path);
  79                         }
  80                         else
  81                         {
  82                                 throw new FileNotFoundException();
  83                         }
  84 #endif
  85                 }
  86         }
  87 }       // namespace System.IO.Private