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

   1 //
   2 // ContentDispositionHeaderValue.cs
   3 //
   4 // Authors:
   5 //      Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (C) 2012 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 using System.Globalization;
  32
  33 namespace System.Net.Http.Headers
  34 {
  35         public class ContentDispositionHeaderValue : ICloneable
  36         {
  37                 string dispositionType;
  38                 List<NameValueHeaderValue> parameters;
  39
  40                 private ContentDispositionHeaderValue ()
  41                 {
  42                 }
  43
  44                 public ContentDispositionHeaderValue (string dispositionType)
  45                 {
  46                         DispositionType = dispositionType;
  47                 }
  48
  49                 protected ContentDispositionHeaderValue (ContentDispositionHeaderValue source)
  50                 {
  51                         if (source == null)
  52                                 throw new ArgumentNullException ("source");
  53
  54                         dispositionType = source.dispositionType;
  55                         if (source.parameters != null) {
  56                                 foreach (var item in source.parameters)
  57                                         Parameters.Add (new NameValueHeaderValue (item));
  58                         }
  59                 }
  60
  61                 public DateTimeOffset? CreationDate {
  62                         get {
  63                                 return GetDateValue ("creation-date");
  64                         }
  65                         set {
  66                                 SetDateValue ("creation-date", value);
  67                         }
  68                 }
  69
  70                 public string DispositionType {
  71                         get {
  72                                 return dispositionType;
  73                         }
  74                         set {
  75                                 Parser.Token.Check (value);
  76                                 dispositionType = value;
  77                         }
  78                 }
  79
  80                 public string FileName {
  81                         get {
  82                                 var value = FindParameter ("filename");
  83                                 if (value == null)
  84                                         return null;
  85
  86                                 return DecodeValue (value, false);
  87                         }
  88                         set {
  89                                 if (value != null)
  90                                         value = EncodeBase64Value (value);
  91
  92                                 SetValue ("filename", value);
  93                         }
  94                 }
  95
  96                 public string FileNameStar {
  97                         get {
  98                                 var value = FindParameter ("filename*");
  99                                 if (value == null)
 100                                         return null;
 101
 102                                 return DecodeValue (value, true);
 103                         }
 104                         set {
 105                                 if (value != null)
 106                                         value = EncodeRFC5987 (value);
 107
 108                                 SetValue ("filename*", value);
 109                         }
 110                 }
 111
 112                 public DateTimeOffset? ModificationDate {
 113                         get {
 114                                 return GetDateValue ("modification-date");
 115                         }
 116                         set {
 117                                 SetDateValue ("modification-date", value);
 118                         }
 119                 }
 120
 121                 public string Name {
 122                         get {
 123                                 return FindParameter ("name");
 124                         }
 125                         set {
 126                                 SetValue ("name", value);
 127                         }
 128                 }
 129
 130                 public ICollection<NameValueHeaderValue> Parameters {
 131                         get {
 132                                 return parameters ?? (parameters = new List<NameValueHeaderValue> ());
 133                         }
 134                 }
 135
 136                 public DateTimeOffset? ReadDate {
 137                         get {
 138                                 return GetDateValue ("read-date");
 139                         }
 140                         set {
 141                                 SetDateValue ("read-date", value);
 142                         }
 143                 }
 144
 145                 public long? Size {
 146                         get {
 147                                 var found = FindParameter ("size");
 148                                 long result;
 149                                 if (Parser.Long.TryParse (found, out result))
 150                                         return result;
 151
 152                                 return null;
 153                         }
 154                         set {
 155                                 if (value == null) {
 156                                         SetValue ("size", null);
 157                                         return;
 158                                 }
 159
 160                                 if (value < 0)
 161                                         throw new ArgumentOutOfRangeException ("value");
 162
 163                                 SetValue ("size", value.Value.ToString (CultureInfo.InvariantCulture));
 164                         }
 165                 }
 166
 167                 object ICloneable.Clone ()
 168                 {
 169                         return new ContentDispositionHeaderValue (this);
 170                 }
 171
 172                 public override bool Equals (object obj)
 173                 {
 174                         var source = obj as ContentDispositionHeaderValue;
 175                         return source != null &&
 176                                 string.Equals (source.dispositionType, dispositionType, StringComparison.OrdinalIgnoreCase) &&
 177                                 source.parameters.SequenceEqual (parameters);
 178                 }
 179
 180                 string FindParameter (string name)
 181                 {
 182                         if (parameters == null)
 183                                 return null;
 184
 185                         foreach (var entry in parameters) {
 186                                 if (string.Equals (entry.Name, name, StringComparison.OrdinalIgnoreCase))
 187                                         return entry.Value;
 188                         }
 189
 190                         return null;
 191                 }
 192
 193                 DateTimeOffset? GetDateValue (string name)
 194                 {
 195                         var value = FindParameter (name);
 196                         if (value == null || value == null)
 197                                 return null;
 198
 199                         if (value.Length < 3)
 200                                 return null;
 201
 202                         if (value[0] == '\"')
 203                                 value = value.Substring (1, value.Length - 2);
 204
 205                         DateTimeOffset offset;
 206                         if (Lexer.TryGetDateValue (value, out offset))
 207                                 return offset;
 208
 209                         return null;
 210                 }
 211
 212                 static string EncodeBase64Value (string value)
 213                 {
 214                         for (int i = 0; i < value.Length; ++i) {
 215                                 var ch = value[i];
 216                                 if (ch > 127) {
 217                                         var encoding = Encoding.UTF8;
 218                                         return string.Format ("\"=?{0}?B?{1}?=\"",
 219                                                 encoding.WebName, Convert.ToBase64String (encoding.GetBytes (value)));
 220                                 }
 221                         }
 222
 223                         if (!Lexer.IsValidToken (value))
 224                                 return "\"" + value + "\"";
 225
 226                         return value;
 227                 }
 228
 229                 static string EncodeRFC5987 (string value)
 230                 {
 231                         var encoding = Encoding.UTF8;
 232                         StringBuilder sb = new StringBuilder (value.Length + 11);
 233                         sb.Append (encoding.WebName);
 234                         sb.Append ('\'');
 235                         sb.Append ('\'');
 236
 237                         for (int i = 0; i < value.Length; ++i) {
 238                                 var ch = value[i];
 239                                 if (ch > 127) {
 240                                         foreach (var b in encoding.GetBytes (new[] { ch })) {
 241                                                 sb.Append ('%');
 242                                                 sb.Append (b.ToString ("X2"));
 243                                         }
 244
 245                                         continue;
 246                                 }
 247
 248                                 sb.Append (ch);
 249                         }
 250
 251                         return sb.ToString ();
 252                 }
 253
 254                 static string DecodeValue (string value, bool extendedNotation)
 255                 {
 256                         //
 257                         // A short (length <= 78 characters)
 258                         // parameter value containing only non-`tspecials' characters SHOULD be
 259                         // represented as a single `token'.  A short parameter value containing
 260                         // only ASCII characters, but including `tspecials' characters, SHOULD
 261                         // be represented as `quoted-string'.  Parameter values longer than 78
 262                         // characters, or which contain non-ASCII characters, MUST be encoded as
 263                         // specified in [RFC 2184].
 264                         //
 265                         if (value.Length < 2)
 266                                 return value;
 267
 268                         string[] sep;
 269                         Encoding encoding;
 270
 271                         // Quoted string
 272                         if (value[0] == '\"') {
 273                                 //
 274                                 // Is Base64 encoded ?
 275                                 // encoded-word := "=?" charset "?" encoding "?" encoded-text "?="
 276                                 //
 277                                 sep = value.Split ('?');
 278                                 if (sep.Length != 5 || sep[0] != "\"=" || sep[4] != "=\"" || (sep[2] != "B" && sep[2] != "b"))
 279                                         return value;
 280
 281                                 try {
 282                                         encoding = Encoding.GetEncoding (sep[1]);
 283                                         return encoding.GetString (Convert.FromBase64String (sep[3]));
 284                                 } catch {
 285                                         return value;
 286                                 }
 287                         }
 288
 289                         if (!extendedNotation)
 290                                 return value;
 291
 292                         //
 293                         // RFC 5987: Charset/Language Encoding
 294                         //
 295                         sep = value.Split ('\'');
 296                         if (sep.Length != 3)
 297                                 return null;
 298
 299                         try {
 300                                 encoding = Encoding.GetEncoding (sep[0]);
 301                         } catch {
 302                                 return null;
 303                         }
 304
 305                         // TODO: What to do with sep[1] language
 306
 307                         value = sep[2];
 308
 309                         int pct_encoded = value.IndexOf ('%');
 310                         if (pct_encoded < 0)
 311                                 return value;
 312
 313                         StringBuilder sb = new StringBuilder ();
 314                         byte[] buffer = null;
 315                         int buffer_pos = 0;
 316
 317                         for (int i = 0; i < value.Length;) {
 318                                 var ch = value[i];
 319                                 if (ch == '%') {
 320                                         var unescaped = ch;
 321                                         ch = Uri.HexUnescape (value, ref i);
 322                                         if (ch != unescaped) {
 323                                                 if (buffer == null)
 324                                                         buffer = new byte[value.Length - i + 1];
 325
 326                                                 buffer[buffer_pos++] = (byte) ch;
 327                                                 continue;
 328                                         }
 329                                 } else {
 330                                         ++i;
 331                                 }
 332
 333                                 if (buffer_pos != 0) {
 334                                         sb.Append (encoding.GetChars (buffer, 0, buffer_pos));
 335                                         buffer_pos = 0;
 336                                 }
 337
 338                                 sb.Append (ch);
 339                         }
 340
 341                         if (buffer_pos != 0) {
 342                                 sb.Append (encoding.GetChars (buffer, 0, buffer_pos));
 343                         }
 344
 345                         return sb.ToString ();
 346                 }
 347
 348                 public override int GetHashCode ()
 349                 {
 350                         return dispositionType.ToLowerInvariant ().GetHashCode () ^
 351                                 HashCodeCalculator.Calculate (parameters);
 352                 }
 353
 354                 public static ContentDispositionHeaderValue Parse (string input)
 355                 {
 356                         ContentDispositionHeaderValue value;
 357                         if (TryParse (input, out value))
 358                                 return value;
 359
 360                         throw new FormatException (input);
 361                 }
 362
 363                 void SetDateValue (string key, DateTimeOffset? value)
 364                 {
 365                         SetValue (key, value == null ? null : ("\"" + value.Value.ToString ("r", CultureInfo.InvariantCulture)) + "\"");
 366                 }
 367
 368                 void SetValue (string key, string value)
 369                 {
 370                         if (parameters == null)
 371                                 parameters = new List<NameValueHeaderValue> ();
 372
 373                         parameters.SetValue (key, value);
 374                 }
 375
 376                 public override string ToString ()
 377                 {
 378                         return dispositionType + CollectionExtensions.ToString (parameters);
 379                 }
 380
 381                 public static bool TryParse (string input, out ContentDispositionHeaderValue parsedValue)
 382                 {
 383                         parsedValue = null;
 384
 385                         var lexer = new Lexer (input);
 386                         var t = lexer.Scan ();
 387                         if (t.Kind != Token.Type.Token)
 388                                 return false;
 389
 390                         List<NameValueHeaderValue> parameters = null;
 391                         var type = lexer.GetStringValue (t);
 392
 393                         t = lexer.Scan ();
 394
 395                         switch (t.Kind) {
 396                         case Token.Type.SeparatorSemicolon:
 397                                 if (!NameValueHeaderValue.TryParseParameters (lexer, out parameters, out t) || t != Token.Type.End)
 398                                         return false;
 399                                 break;
 400                         case Token.Type.End:
 401                                 break;
 402                         default:
 403                                 return false;
 404                         }
 405
 406                         parsedValue = new ContentDispositionHeaderValue () {
 407                                 dispositionType = type,
 408                                 parameters = parameters
 409                         };
 410
 411                         return true;
 412                 }
 413         }
 414 }