mcs/class/corlib/System.IO/TextReader.cs

   1 //\r
   2 // System.IO.TextReader\r
   3 //\r
   4 // Authors:\r
   5 //   Marcin Szczepanski (marcins@zipworld.com.au)\r
   6 //   Miguel de Icaza (miguel@gnome.org)\r
   7 //\r
   8
   9 //
  10 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31 \r
  32 using System;\r
  33 using System.Runtime.InteropServices;\r
  34 \r
  35 namespace System.IO {\r
  36 \r
  37         [Serializable]\r
  38         public abstract class TextReader : MarshalByRefObject, IDisposable {\r
  39                 \r
  40                 protected TextReader() { }\r
  41                 \r
  42                 public static readonly TextReader Null;\r
  43                 \r
  44                 public virtual void Close()\r
  45                 { \r
  46                         Dispose(true);\r
  47                 }\r
  48 \r
  49                 void System.IDisposable.Dispose()\r
  50                 {\r
  51                         Dispose(true);\r
  52                 }\r
  53 \r
  54                 protected virtual void Dispose( bool disposing )\r
  55                 {\r
  56                         return;\r
  57                 }\r
  58                 \r
  59                 public virtual int Peek()\r
  60                 {\r
  61                         return -1;\r
  62                 }\r
  63                 \r
  64                 public virtual int Read()\r
  65                 {\r
  66                         return -1;\r
  67                 }\r
  68                 \r
  69
  70                 public virtual int Read ([In, Out] char[] buffer, int index, int count)\r
  71                 {\r
  72                         int c, i;\r
  73                         \r
  74                         for (i = 0; i < count; i++) {\r
  75                                 if ((c = Read ()) == -1)\r
  76                                         return i;\r
  77                                 buffer [index + i] = (char)c;\r
  78                         }\r
  79                         \r
  80                         return i;\r
  81                 }\r
  82                 \r
  83                 public virtual int ReadBlock ([In, Out] char [] buffer, int index, int count)\r
  84                 {\r
  85                         int total_read_count = 0;\r
  86                         int current_read_count = 0;\r
  87 \r
  88                         do {\r
  89                                 current_read_count = Read (buffer, index, count);\r
  90                                 index += current_read_count;\r
  91                                 total_read_count += current_read_count;\r
  92                                 count -= current_read_count;\r
  93                         } while (current_read_count != 0 && count > 0);\r
  94 \r
  95                         return total_read_count;\r
  96                 }\r
  97 \r
  98                 public virtual string ReadLine()\r
  99                 { \r
 100                         return String.Empty;\r
 101                 }\r
 102 \r
 103                 public virtual string ReadToEnd()\r
 104                 { \r
 105                         return String.Empty;\r
 106                 }\r
 107 \r
 108                 public static TextReader Synchronized (TextReader reader)\r
 109                 {\r
 110                         if (reader == null)\r
 111                                 throw new ArgumentNullException ("reader is null");\r
 112                         if (reader is SynchronizedReader)\r
 113                                 return reader;\r
 114 \r
 115                         return new SynchronizedReader (reader);\r
 116                 }       \r
 117         }\r
 118 \r
 119         //\r
 120         // Synchronized Reader implementation, used internally.\r
 121         //\r
 122         [Serializable]\r
 123         internal class SynchronizedReader : TextReader {\r
 124                 TextReader reader;\r
 125                 \r
 126                 public SynchronizedReader (TextReader reader)\r
 127                 {\r
 128                         this.reader = reader;\r
 129                 }\r
 130 \r
 131                 public override void Close ()\r
 132                 {\r
 133                         lock (this){\r
 134                                 reader.Close ();\r
 135                         }\r
 136                 }\r
 137 \r
 138                 public override int Peek ()\r
 139                 {\r
 140                         lock (this){\r
 141                                 return reader.Peek ();\r
 142                         }\r
 143                 }\r
 144 \r
 145                 public override int ReadBlock (char [] buffer, int index, int count)\r
 146                 {\r
 147                         lock (this){\r
 148                                 return reader.ReadBlock (buffer, index, count);\r
 149                         }\r
 150                 }\r
 151 \r
 152                 public override string ReadLine ()\r
 153                 {\r
 154                         lock (this){\r
 155                                 return reader.ReadLine ();\r
 156                         }\r
 157                 }\r
 158 \r
 159                 public override string ReadToEnd ()\r
 160                 {\r
 161                         lock (this){\r
 162                                 return reader.ReadToEnd ();\r
 163                         }\r
 164                 }\r
 165 #region Read Methods\r
 166                 public override int Read ()\r
 167                 {\r
 168                         lock (this){\r
 169                                 return reader.Read ();\r
 170                         }\r
 171                 }\r
 172 \r
 173                 public override int Read (char [] buffer, int index, int count)\r
 174                 {\r
 175                         lock (this){\r
 176                                 return reader.Read (buffer, index, count);\r
 177                         }\r
 178                 }\r
 179 #endregion\r
 180                 \r
 181         }\r
 182 }\r