mcs/class/System.Net.Http/System.Net.Http.Headers/RangeHeaderValue.cs

   1 //
   2 // RangeHeaderValue.cs
   3 //
   4 // Authors:
   5 //      Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (C) 2011 Xamarin Inc (http://www.xamarin.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.Collections.Generic;
  30 using System.Text;
  31
  32 namespace System.Net.Http.Headers
  33 {
  34         public class RangeHeaderValue : ICloneable
  35         {
  36                 List<RangeItemHeaderValue> ranges;
  37                 string unit;
  38
  39                 public RangeHeaderValue ()
  40                 {
  41                         unit = "bytes";
  42                 }
  43
  44                 public RangeHeaderValue (long? from, long? to)
  45                         : this ()
  46                 {
  47                         Ranges.Add (new RangeItemHeaderValue (from, to));
  48                 }
  49
  50                 private RangeHeaderValue (RangeHeaderValue source)
  51                         : this ()
  52                 {
  53                         if (source.ranges != null) {
  54                                 foreach (var item in source.ranges)
  55                                         Ranges.Add (item);
  56                         }
  57                 }
  58
  59                 public ICollection<RangeItemHeaderValue> Ranges {
  60                         get {
  61                                 return ranges ?? (ranges = new List<RangeItemHeaderValue> ());
  62                         }
  63                 }
  64
  65                 public string Unit {
  66                         get {
  67                                 return unit;
  68                         }
  69                         set {
  70                                 if (value == null)
  71                                         throw new ArgumentNullException ("Unit");
  72
  73                                 Parser.Token.Check (value);
  74
  75                                 unit = value;
  76                         }
  77                 }
  78
  79                 object ICloneable.Clone ()
  80                 {
  81                         return new RangeHeaderValue (this);
  82                 }
  83
  84                 public override bool Equals (object obj)
  85                 {
  86                         var source = obj as RangeHeaderValue;
  87                         if (source == null)
  88                                 return false;
  89
  90                         return string.Equals (source.Unit, Unit, StringComparison.OrdinalIgnoreCase) &&
  91                                 source.ranges.SequenceEqual (ranges);
  92                 }
  93
  94                 public override int GetHashCode ()
  95                 {
  96                         return Unit.ToLowerInvariant ().GetHashCode () ^ HashCodeCalculator.Calculate (ranges);
  97                 }
  98
  99                 public static RangeHeaderValue Parse (string input)
 100                 {
 101                         RangeHeaderValue value;
 102                         if (TryParse (input, out value))
 103                                 return value;
 104
 105                         throw new FormatException (input);
 106                 }
 107
 108                 public static bool TryParse (string input, out RangeHeaderValue parsedValue)
 109                 {
 110                         parsedValue = null;
 111
 112                         var lexer = new Lexer (input);
 113                         var t = lexer.Scan ();
 114                         if (t != Token.Type.Token)
 115                                 return false;
 116
 117                         var value = new RangeHeaderValue ();
 118                         value.unit = lexer.GetStringValue (t);
 119
 120                         t = lexer.Scan ();
 121                         if (t != Token.Type.SeparatorEqual)
 122                                 return false;
 123
 124                         bool token_read;
 125                         do {
 126                                 int? from = null, to = null;
 127                                 int number;
 128                                 token_read = false;
 129
 130                                 t = lexer.Scan ();
 131                                 switch (t.Kind) {
 132                                 case Token.Type.SeparatorDash:
 133                                         t = lexer.Scan ();
 134                                         if (!lexer.TryGetNumericValue (t, out number))
 135                                                 return false;
 136
 137                                         to = number;
 138                                         break;
 139                                 case Token.Type.Token:
 140                                         string s = lexer.GetStringValue (t);
 141                                         var values = s.Split (new [] { '-' }, StringSplitOptions.RemoveEmptyEntries);
 142                                         if (!int.TryParse (values[0], out number))
 143                                                 return false;
 144
 145                                         switch (values.Length) {
 146                                         case 1:
 147                                                 t = lexer.Scan ();
 148                                                 switch (t.Kind) {
 149                                                 case Token.Type.SeparatorDash:
 150                                                         from = number;
 151
 152                                                         t = lexer.Scan ();
 153                                                         if (t != Token.Type.Token) {
 154                                                                 token_read = true;
 155                                                                 break;
 156                                                         }
 157
 158                                                         if (!lexer.TryGetNumericValue (t, out number))
 159                                                                 return false;
 160
 161                                                         to = number;
 162                                                         if (to < from)
 163                                                                 return false;
 164
 165                                                         break;
 166                                                 default:
 167                                                         return false;
 168                                                 }
 169                                                 break;
 170                                         case 2:
 171                                                 from = number;
 172
 173                                                 if (!int.TryParse (values[1], out number))
 174                                                         return false;
 175
 176                                                 to = number;
 177                                                 if (to < from)
 178                                                         return false;
 179
 180                                                 break;
 181                                         default:
 182                                                 return false;
 183                                         }
 184
 185                                         break;
 186                                 default:
 187                                         return false;
 188                                 }
 189
 190                                 value.Ranges.Add (new RangeItemHeaderValue (from, to));
 191                                 if (!token_read)
 192                                         t = lexer.Scan ();
 193
 194                         } while (t == Token.Type.SeparatorComma);
 195
 196                         if (t != Token.Type.End)
 197                                 return false;
 198
 199                         parsedValue = value;
 200                         return true;
 201                 }
 202
 203                 public override string ToString ()
 204                 {
 205                         var sb = new StringBuilder (unit);
 206                         sb.Append ("=");
 207                         for (int i = 0; i < Ranges.Count; ++i) {
 208                                 if (i > 0)
 209                                         sb.Append (", ");
 210
 211                                 sb.Append (ranges[i]);
 212                         }
 213
 214                         return sb.ToString ();
 215                 }
 216         }
 217 }