mcs/class/System.Web/System.Web/HttpRequestStream.cs

   1 //
   2 // System.Web.HttpRequestStream
   3 //
   4 // Author:
   5 //   Patrik Torstensson (Patrik.Torstensson@labs2.com)
   6 //
   7
   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 using System;
  29 using System.IO;
  30
  31 namespace System.Web
  32 {
  33         class HttpRequestStream : Stream
  34         {
  35                 byte [] _arrData;
  36                 int _iLength;
  37                 int _iOffset;
  38                 int _iPos;
  39
  40                 internal HttpRequestStream ()
  41                 {
  42                 }
  43
  44                 internal HttpRequestStream (byte [] buffer, int offset, int length)
  45                 {
  46                         Set (buffer, offset, length);
  47                 }
  48
  49                 void Reset ()
  50                 {
  51                         Set (null, 0, 0);
  52                 }
  53
  54                 internal void Set (byte [] buffer, int offset, int length)
  55                 {
  56                         _iPos = 0;
  57                         _iOffset = offset;
  58                         _iLength = length;
  59                         _arrData = buffer;
  60                 }
  61
  62                 public override void Flush ()
  63                 {
  64                 }
  65
  66                 public override void Close ()
  67                 {
  68                         Reset ();
  69                 }
  70
  71                 public override int Read (byte [] buffer, int offset, int length)
  72                 {
  73                         int iBytes = length;
  74
  75                         if (_iPos < _iOffset)
  76                                 _iPos = _iOffset;
  77
  78                         if (_iPos + length > _iOffset + _iLength) {
  79                                 iBytes = (int) _iOffset + _iLength - _iPos;
  80                         }
  81
  82                         if (iBytes <= 0) {
  83                                 return 0;
  84                         }
  85
  86                         Buffer.BlockCopy (_arrData, _iPos, buffer, offset, iBytes);
  87                         _iPos += iBytes;
  88
  89                         return iBytes;
  90                 }
  91
  92                 public override long Seek (long offset, SeekOrigin origin)
  93                 {
  94                         switch (origin) {
  95                         case SeekOrigin.Begin:
  96                                 if (offset > _arrData.Length) {
  97                                         throw new ArgumentException ();
  98                                 }
  99                                 _iPos = (int) offset;
 100                                 break;
 101                         case SeekOrigin.Current:
 102                                 if (((long) _iPos + offset > _arrData.Length) || (_iPos + (int) offset < 0)) {
 103                                         throw new ArgumentException ();
 104                                 }
 105                                 _iPos += Convert.ToInt32 (offset);
 106                                 break;
 107
 108                         case SeekOrigin.End:
 109                                 if (_arrData.Length - offset < 0) {
 110                                         throw new ArgumentException();
 111                                 }
 112
 113                                 _iPos = Convert.ToInt32 ( _arrData.Length - offset);
 114                                 break;
 115                         }
 116
 117                         return (long) _iPos;
 118                 }
 119
 120                 public override void SetLength (long length)
 121                 {
 122                         throw new NotSupportedException ();
 123                 }
 124
 125                 public override void Write (byte [] buffer, int offset, int length)
 126                 {
 127                         throw new NotSupportedException ();
 128                 }
 129
 130                 public override bool CanRead {
 131                         get { return true; }
 132                 }
 133
 134                 public override bool CanSeek {
 135                         get { return true; }
 136                 }
 137
 138                 public override bool CanWrite {
 139                         get { return false; }
 140                 }
 141
 142                 public byte [] Data {
 143                         get { return _arrData; }
 144                 }
 145
 146                 public int DataLength {
 147                         get { return _iLength; }
 148                 }
 149
 150                 public int DataOffset {
 151                         get { return _iOffset; }
 152                 }
 153
 154                 public override long Length {
 155                         get { return (long) _arrData.Length; }
 156                 }
 157
 158                 public override long Position {
 159                         get { return (long) _iPos; }
 160
 161                         set { Seek (value, SeekOrigin.Begin); }
 162                 }
 163         }
 164 }
 165