mcs/class/System.Data/System.Data.SqlClient/SqlXmlTextReader.cs

   1 //
   2 // System.Data.SqlClient.SqlXmlTextReader.cs
   3 //
   4 // Author:
   5 //   Rodrigo Moya (rodrigo@ximian.com)
   6 //   Daniel Morgan (danmorg@sc.rr.com)
   7 //   Tim Coleman (tim@timcoleman.com)
   8 //
   9 // (C) Ximian, Inc 2002
  10 // (C) Daniel Morgan 2002
  11 // Copyright (C) Tim Coleman, 2002
  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 using Mono.Data.Tds.Protocol;
  38 using System;
  39 using System.IO;
  40 using System.Text;
  41
  42 namespace System.Data.SqlClient {
  43         internal sealed class SqlXmlTextReader : TextReader, IDisposable
  44         {
  45                 #region Fields
  46
  47                 bool disposed = false;
  48                 bool eof = false;
  49                 SqlDataReader reader;
  50                 string localBuffer = "<results>";
  51                 int position;
  52
  53                 #endregion // Fields
  54
  55                 #region Constructors
  56
  57                 internal SqlXmlTextReader (SqlDataReader reader)
  58                         : base ()
  59                 {
  60                         this.reader = reader;
  61                 }
  62
  63                 #endregion
  64
  65                 #region Methods
  66
  67                 public override void Close()
  68                 {
  69                         reader.Close ();
  70                 }
  71
  72                 protected override void Dispose (bool disposing)
  73                 {
  74                         if (!disposed) {
  75                                 if (disposing) {
  76                                         Close ();
  77                                         ((IDisposable) reader).Dispose ();
  78                                 }
  79                                 disposed = true;
  80                         }
  81                 }
  82
  83                 void IDisposable.Dispose ()
  84                 {
  85                         Dispose (true);
  86                         GC.SuppressFinalize (this);
  87                 }
  88
  89                 private bool GetNextBuffer ()
  90                 {
  91                         if (eof) {
  92                                 localBuffer = null;
  93                                 return false;
  94                         }
  95
  96                         position = 0;
  97                         if (reader.Read ())
  98                                 localBuffer = reader.GetString (0);
  99                         else if (reader.NextResult () && reader.Read ())
 100                                 localBuffer = reader.GetString (0);
 101                         else {
 102                                 eof = true;
 103                                 localBuffer = "</results>";
 104                         }
 105                         return true;
 106                 }
 107
 108                 public override int Peek ()
 109                 {
 110                         bool moreResults;
 111                         if (localBuffer == null || localBuffer.Length == 0) {
 112                                 moreResults = GetNextBuffer ();
 113                                 if (!moreResults)
 114                                         return -1;
 115                         }
 116                         if (eof && position >= localBuffer.Length)
 117                                 return -1;
 118                         return (int) localBuffer[position];
 119                 }
 120
 121                 public override int Read ()
 122                 {
 123                         int result = Peek ();
 124                         position += 1;
 125                         if (!eof && position >= localBuffer.Length)
 126                                 GetNextBuffer ();
 127                         return result;
 128                 }
 129
 130                 public override int Read (char[] buffer, int index, int count)
 131                 {
 132                         bool moreResults = true;
 133                         int countRead = 0;
 134
 135                         if (localBuffer == null)
 136                                 moreResults = GetNextBuffer ();
 137
 138                         while (moreResults && count - countRead > localBuffer.Length - position) {
 139                                 localBuffer.CopyTo (position, buffer, index + countRead, localBuffer.Length);
 140                                 countRead += localBuffer.Length;
 141                                 moreResults = GetNextBuffer ();
 142                         }
 143                         if (moreResults && countRead < count) {
 144                                 localBuffer.CopyTo (position, buffer, index + countRead, count - countRead);
 145                                 position += count - countRead;
 146                         }
 147
 148                         return countRead;
 149                 }
 150
 151                 public override int ReadBlock (char[] buffer, int index, int count)
 152                 {
 153                         return Read (buffer, index, count);
 154                 }
 155
 156                 public override string ReadLine ()
 157                 {
 158                         bool moreResults = true;
 159                         string outBuffer;
 160                         if (localBuffer == null)
 161                                 moreResults = GetNextBuffer ();
 162                         if (!moreResults)
 163                                 return null;
 164                         outBuffer = localBuffer;
 165                         GetNextBuffer ();
 166                         return outBuffer;
 167                 }
 168
 169                 public override string ReadToEnd ()
 170                 {
 171                         string outBuffer = String.Empty;
 172
 173                         bool moreResults = true;
 174                         if (localBuffer == null)
 175                                 moreResults = GetNextBuffer ();
 176                         while (moreResults) {
 177                                 outBuffer += localBuffer;
 178                                 moreResults = GetNextBuffer ();
 179                         }
 180                         return outBuffer;
 181                 }
 182
 183                 #endregion // Methods
 184         }
 185 }