mcs/class/System.Web/System.Web/StaticFileHandler.cs

   1 //
   2 // System.Web.StaticFileHandler
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2002 Ximian, Inc (http://www.ximian.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Globalization;
  33 using System.IO;
  34 using System.Web.Util;
  35
  36 namespace System.Web
  37 {
  38         class StaticFileHandler : IHttpHandler
  39         {
  40                 static bool runningWindows = RunningOnWindows ();
  41
  42                 static bool RunningOnWindows ()
  43                 {
  44                         int pid = (int)Environment.OSVersion.Platform;
  45                         return (pid != 4 && pid != 128);
  46                 }
  47
  48                 static bool ValidFileName (string fileName)
  49                 {
  50                         if (!runningWindows)
  51                                 return true;
  52
  53                         if (fileName == null || fileName.Length == 0)
  54                                 return false;
  55
  56                         return (!StrUtils.EndsWith (fileName, " ") && !StrUtils.EndsWith (fileName, "."));
  57                 }
  58
  59                 public void ProcessRequest (HttpContext context)
  60                 {
  61                         HttpRequest request = context.Request;
  62                         HttpResponse response = context.Response;
  63                         string fileName = request.PhysicalPath;
  64                         FileInfo fi = new FileInfo (fileName);
  65                         if (!fi.Exists || !ValidFileName (fileName))
  66                                 throw new HttpException (404, "File '" + request.FilePath + "' not found.");
  67
  68                         if ((fi.Attributes & FileAttributes.Directory) != 0) {
  69                                 response.Redirect (request.Path + '/');
  70                                 return;
  71                         }
  72
  73                         string strHeader = request.Headers ["If-Modified-Since"];
  74                         try {
  75                                 if (strHeader != null) {
  76                                         DateTime dtIfModifiedSince = DateTime.ParseExact (strHeader, "r", null);
  77                                         DateTime ftime;
  78 #if TARGET_JVM
  79                                         try
  80                                         {
  81                                                 ftime = fi.LastWriteTime.ToUniversalTime ();
  82                                         }
  83                                         catch (NotSupportedException)
  84                                         {
  85                                                 // The file is in a WAR, it might be modified with last redeploy.
  86                                                 try {
  87                                                         ftime = (DateTime) AppDomain.CurrentDomain.GetData (".appStartTime");
  88                                                 }
  89                                                 catch {
  90                                                         ftime = DateTime.MaxValue;
  91                                                 }
  92                                         }
  93 #else
  94                                         ftime = fi.LastWriteTime.ToUniversalTime ();
  95 #endif
  96                                         if (ftime <= dtIfModifiedSince) {
  97                                                 response.StatusCode = 304;
  98                                                 return;
  99                                         }
 100                                 }
 101                         } catch { }
 102
 103                         try {
 104                                 DateTime lastWT = fi.LastWriteTime.ToUniversalTime ();
 105                                 response.AddHeader ("Last-Modified", lastWT.ToString ("r"));
 106
 107                                 response.ContentType = MimeTypes.GetMimeType (fileName);
 108                                 response.TransmitFile (fileName, true);
 109                         } catch (Exception) {
 110                                 throw new HttpException (403, "Forbidden.");
 111                         }
 112                 }
 113
 114                 public bool IsReusable {
 115                         get { return true; }
 116                 }
 117         }
 118 }
 119