Example #1
0
        /// <summary>
        /// Parses the next <see cref="BList"/> from the stream.
        /// </summary>
        /// <param name="stream">The stream to parse from.</param>
        /// <returns>The parsed <see cref="BList"/>.</returns>
        /// <exception cref="InvalidBencodeException{BList}">Invalid bencode</exception>
        public override BList Parse(BencodeStream stream)
        {
            if (stream == null)
            {
                throw new ArgumentNullException("stream");
            }

            if (stream.Length < MinimumLength)
            {
                throw InvalidBencodeException <BList> .BelowMinimumLength(MinimumLength, stream.Length, stream.Position);
            }

            // Lists must start with 'l'
            if (stream.ReadChar() != 'l')
            {
                throw InvalidBencodeException <BList> .UnexpectedChar('l', stream.ReadPreviousChar(), stream.Position);
            }

            var list = new BList();

            // Loop until next character is the end character 'e' or end of stream
            while (stream.Peek() != 'e' && stream.Peek() != -1)
            {
                // Decode next object in stream
                var bObject = BencodeParser.Parse(stream);
                list.Add(bObject);
            }

            if (stream.ReadChar() != 'e')
            {
                if (stream.EndOfStream)
                {
                    throw InvalidBencodeException <BList> .MissingEndChar();
                }
                throw InvalidBencodeException <BList> .InvalidEndChar(stream.ReadPreviousChar(), stream.Position);
            }

            return(list);
        }
        /// <summary>
        /// Parses the next <see cref="BDictionary"/> from the stream and its contained keys and values.
        /// </summary>
        /// <param name="stream">The stream to parse from.</param>
        /// <returns>The parsed <see cref="BDictionary"/>.</returns>
        /// <exception cref="InvalidBencodeException{BDictionary}">Invalid bencode</exception>
        public override BDictionary Parse(BencodeStream stream)
        {
            if (stream == null)
            {
                throw new ArgumentNullException("stream");
            }

            var startPosition = stream.Position;

            if (stream.Length < MinimumLength)
            {
                throw InvalidBencodeException <BDictionary> .BelowMinimumLength(MinimumLength, stream.Length, startPosition);
            }

            // Dictionaries must start with 'd'
            if (stream.ReadChar() != 'd')
            {
                throw InvalidBencodeException <BDictionary> .UnexpectedChar('d', stream.ReadPreviousChar(), startPosition);
            }

            var dictionary = new BDictionary();

            // Loop until next character is the end character 'e' or end of stream
            while (stream.Peek() != 'e' && stream.Peek() != -1)
            {
                BString key;
                try
                {
                    // Decode next string in stream as the key
                    key = BencodeParser.Parse <BString>(stream);
                }
                catch (BencodeException <BString> ex)
                {
                    throw InvalidException("Could not parse dictionary key. Keys must be strings.", ex, startPosition);
                }

                IBObject value;
                try
                {
                    // Decode next object in stream as the value
                    value = BencodeParser.Parse(stream);
                }
                catch (BencodeException ex)
                {
                    throw InvalidException(
                              string.Format("Could not parse dictionary value for the key '{0}'. There needs to be a value for each key.", key),
                              ex, startPosition);
                }

                if (dictionary.ContainsKey(key))
                {
                    throw InvalidException(
                              string.Format("The dictionary already contains the key '{0}'. Duplicate keys are not supported.", key), startPosition);
                }

                dictionary.Add(key, value);
            }

            if (stream.ReadChar() != 'e')
            {
                if (stream.EndOfStream)
                {
                    throw InvalidBencodeException <BDictionary> .MissingEndChar();
                }
                throw InvalidBencodeException <BDictionary> .InvalidEndChar(stream.ReadPreviousChar(), stream.Position);
            }

            return(dictionary);
        }