public class LimitedStream : Stream {
        private Stream stream;
        private long limit;

        public LimitedStream(Stream stream, long limit) {
            this.stream = stream;
            this.limit  = limit; 
        }

        public override bool CanRead  { get { return this.stream.CanRead ; } }
        public override bool CanSeek  { get { return this.stream.CanSeek ; } }
        public override bool CanWrite { get { return this.stream.CanWrite; } }
        public override long Length   { get { return this.stream.Length  ; } }

        public override long Position {
            get { return this.stream.Position; }
            set { this.stream.Position = value; }
        }

        public override void Flush() {
            this.stream.Flush();
        }

        public override int Read(byte[] buffer, int offset, int count) {
            Debug.Assert(0 <= Position);
            long overlimit = Position + count - (limit + 1); // +1 because we need to read beyond the limit to report an error
            if (0 < overlimit) {
                if (limit < Position) {
                    // Not interesting state but we need to check it.
                    throw new XmlException("Attempt to read beyond the limit ...");
                }
                Debug.Assert(overlimit < count);
                count -= (int)overlimit;
            }
            int result = this.stream.Read(buffer, offset, count);
            if (limit < Position) {
                // It may have sence to give more info in the exception, like URI ???
                throw new XmlException("Attempt to read beyond the limit ...");
            }
            return result;
        }

        public override long Seek(long offset, SeekOrigin origin) {
            return this.stream.Seek(offset, origin);
        }

        public override void SetLength(long value) {
            this.stream.SetLength(value);
        }

        public override void Write(byte[] buffer, int offset, int count) {
            this.stream.Write(buffer, offset, count);
        }
    }