MessagePack serialization is broken for negative integers

[Archie3d]

Hi 👋 , There are seem to be some unhandled cases in the MessagePack serializer:

• fromData does not handle cases 0xd0, 0xd1, 0xd2, and 0xd3:

  ...
      else if (d == 0xd0)
      {
          return int(is.readByte());
      }
      else if (d == 0xd1)
      {
          return int(is.readShortBigEndian());
      }
      else if (d == 0xd2)
      {
          return is.readIntBigEndian();
      }
      else if (d == 0xd3)
      {
          return is.readInt64BigEndian();
      }
  ...

• toData code reads

  ...
          else if (v >= 32768)
          {
              os.writeByte (char (0xd1));
              os.writeShortBigEndian (short (v));
          }
          else if (v >= 2147483648)
          {
              os.writeByte (char (0xd2));
              os.writeIntBigEndian (int (v));
          }
  ...

  has to be

  ...
          else if (v >= -32768)
          {
              os.writeByte (char (0xd1));
              os.writeShortBigEndian (short (v));
          }
          else if (v >= -2147483648LL)
          {
              os.writeByte (char (0xd2));
              os.writeIntBigEndian (int (v));
          }
  ...

• Also on line 167:

      else
      {
          os.writeByte (char (0xdc));
          os.writeIntBigEndian (n);
      }

  must be

      else
      {
          os.writeByte (char (0xdd));
          os.writeIntBigEndian (n);
      }

Thanks!