/// <summary> /// Decodes a BEncodedList from the given StreamReader /// </summary> /// <param name="reader"></param> internal override void DecodeInternal(RawReader reader) { try { if (reader.ReadByte() != 'l') // Remove the leading 'l' { throw new BEncodingException("Invalid data found. Aborting"); } while ((reader.PeekChar() != -1) && ((char)reader.PeekChar() != 'e')) { list.Add(BEncodedValue.Decode(reader)); } if (reader.ReadByte() != 'e') // Remove the trailing 'e' { throw new BEncodingException("Invalid data found. Aborting"); } } catch (BEncodingException ex) { throw new BEncodingException("Couldn't decode list", ex); } catch { throw new BEncodingException("Couldn't decode list"); } }
/// <summary> /// Decodes a BEncoded number from the supplied RawReader /// </summary> /// <param name="reader">RawReader containing a BEncoded Number</param> internal override void DecodeInternal(RawReader reader) { var sign = 1; if (reader == null) { throw new ArgumentNullException("reader"); } try { if (reader.ReadByte() != 'i') // remove the leading 'i' { throw new BEncodingException("Invalid data found. Aborting."); } if (reader.PeekChar() == '-') { sign = -1; reader.ReadChar(); } int letter; while (((letter = reader.PeekChar()) != -1) && letter != 'e') { if (letter < '0' || letter > '9') { throw new BEncodingException("Invalid number found."); } number = number * 10 + (letter - '0'); reader.ReadChar(); } if (reader.ReadByte() != 'e') //remove the trailing 'e' { throw new BEncodingException("Invalid data found. Aborting."); } number *= sign; } catch (BEncodingException ex) { throw new BEncodingException("Couldn't decode number", ex); } catch { throw new BEncodingException("Couldn't decode number"); } }
/// <summary> /// Special decoding method for torrent files - allows dictionary attributes to be out of order for the /// overall torrent file, but imposes strict rules on the info dictionary. /// </summary> /// <returns></returns> public static BEncodedDictionary DecodeTorrent(RawReader reader) { BEncodedString key = null; BEncodedValue value = null; var torrent = new BEncodedDictionary(); try { if (reader.ReadByte() != 'd') { throw new BEncodingException("Invalid data found. Aborting"); // Remove the leading 'd' } while ((reader.PeekChar() != -1) && ((char)reader.PeekChar() != 'e')) { key = (BEncodedString)Decode(reader); // keys have to be BEncoded strings if (reader.PeekChar() == 'd') { value = new BEncodedDictionary(); if (key.Text.ToLower().Equals("info")) { ((BEncodedDictionary)value).DecodeInternal(reader, true); } else { ((BEncodedDictionary)value).DecodeInternal(reader, false); } } else { value = Decode(reader); // the value is a BEncoded value } torrent.dictionary.Add(key, value); } if (reader.ReadByte() != 'e') // remove the trailing 'e' { throw new BEncodingException("Invalid data found. Aborting"); } return(torrent); } catch (Exception ex) { throw new BEncodingException("Couldn't decode dictionary", ex); } }
/// <summary> /// Decodes a BEncodedString from the supplied StreamReader /// </summary> /// <param name="reader">The StreamReader containing the BEncodedString</param> internal override void DecodeInternal(RawReader reader) { if (reader == null) { throw new ArgumentNullException("reader"); } int letterCount; var length = string.Empty; try { while ((reader.PeekChar() != -1) && (reader.PeekChar() != ':')) // read in how many characters { length += (char)reader.ReadChar(); // the string is } if (reader.ReadChar() != ':') // remove the ':' { throw new BEncodingException("Invalid data found. Aborting"); } if (!int.TryParse(length, out letterCount)) { throw new BEncodingException(string.Format("Invalid BEncodedString. Length was '{0}' instead of a number", length)); } textBytes = new byte[letterCount]; if (reader.Read(textBytes, 0, letterCount) != letterCount) { throw new BEncodingException("Couldn't decode string"); } } catch (Exception ex) { if (ex is BEncodingException) { throw; } else { throw new BEncodingException("Couldn't decode string", ex); } } }
void DecodeInternal(RawReader reader, bool strictDecoding) { BEncodedString key = null; BEncodedValue value = null; BEncodedString oldkey = null; try { if (reader.ReadByte() != 'd') { throw new BEncodingException("Invalid data found. Aborting"); // Remove the leading 'd' } while ((reader.PeekChar() != -1) && ((char)reader.PeekChar() != 'e')) { key = (BEncodedString)Decode(reader); // keys have to be BEncoded strings if (oldkey != null && oldkey.CompareTo(key) > 0) { if (strictDecoding) { throw new BEncodingException(String.Format("Illegal BEncodedDictionary. The attributes are not ordered correctly. Old key: {0}, New key: {1}", oldkey, key)); } } oldkey = key; value = Decode(reader); // the value is a BEncoded value dictionary.Add(key, value); } if (reader.ReadByte() != 'e') // remove the trailing 'e' { throw new BEncodingException("Invalid data found. Aborting"); } } catch (Exception ex) { throw new BEncodingException("Couldn't decode dictionary", ex); } }
/// <summary> /// Decode BEncoded data in the given RawReader /// </summary> /// <param name="reader">The RawReader containing the BEncoded data</param> /// <returns>BEncodedValue containing the data that was in the stream</returns> public static BEncodedValue Decode(RawReader reader) { if (reader == null) { throw new ArgumentNullException("reader"); } BEncodedValue data; switch ((char)reader.PeekChar()) { case ('i'): // Integer data = new BEncodedNumber(); break; case ('d'): // Dictionary data = new BEncodedDictionary(); break; case ('l'): // List data = new BEncodedList(); break; case ('1'): // String case ('2'): case ('3'): case ('4'): case ('5'): case ('6'): case ('7'): case ('8'): case ('9'): case ('0'): data = new BEncodedString(); break; default: throw new BEncodingException("Could not find what value to decode"); } data.DecodeInternal(reader); return(data); }