mcs/class/System.Web/System.Web/TempFileStream.cs

   1 //
   2 // System.Web.TempFileStream.cs
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // Copyright (C) 2006 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System.IO;
  30 using System.Runtime.InteropServices;
  31 namespace System.Web {
  32         public class TempFileStream : FileStream {
  33                 bool read_mode;
  34                 bool disposed;
  35                 long saved_position;
  36
  37                 public TempFileStream (string name)
  38                         : base (name, FileMode.Create, FileAccess.ReadWrite, FileShare.None, 8192)
  39                 {
  40                 }
  41
  42                 public override bool CanRead {
  43                         get { return read_mode; }
  44                 }
  45
  46                 public override bool CanWrite {
  47                         get { return !read_mode; }
  48                 }
  49
  50                 public void SavePosition ()
  51                 {
  52                         saved_position = Position;
  53                         Position = 0;
  54                 }
  55
  56                 public void RestorePosition ()
  57                 {
  58                         Position = saved_position;
  59                         saved_position = -1;
  60                 }
  61
  62                 public void SetReadOnly ()
  63                 {
  64                         read_mode = true;
  65                         Position = 0;
  66                 }
  67
  68                 public void SetWriteOnly ()
  69                 {
  70                         read_mode = false;
  71                         Position = 0;
  72                 }
  73
  74                 public override void Write (byte [] buffer, int offset, int count)
  75                 {
  76                         if (read_mode)
  77                                 throw new InvalidOperationException ("mode read");
  78
  79                         base.Write (buffer, offset, count);
  80                 }
  81
  82                 public override int Read ([In,Out] byte [] buffer, int offset, int count)
  83                 {
  84                         if (!read_mode)
  85                                 throw new InvalidOperationException ("mode write");
  86
  87                         return base.Read (buffer, offset, count);
  88                 }
  89
  90                 protected override void Dispose (bool disposing)
  91                 {
  92                         if (!disposed) {
  93                                 disposed = true;
  94                                 base.Dispose (disposing);
  95                                 try {
  96                                         File.Delete (Name);
  97                                 } catch {}
  98                         }
  99                 }
 100         }
 101 }
 102