[Tinyos-help] Re: Trouble with modifying BaseStation

[Philip Levis]

On May 2, 2007, at 3:49 AM, Romain Thouvenin wrote:

> On 5/2/07, Romain Thouvenin <romain.thouvenin at gmail.com> wrote:
>> Hi,
>>
>> I'd like to use BaseStation with my Multi-hop Protocol and read the
>> packets in a Java application.
>>
>> So I "migged" the multi-hop packet, wired BaseStationP to the
>> multi-hop component (which provide AM interfaces), and modifyed
>> BaseStationP so that it always use the multi-hop AM type and compute
>> the proper length of the packet.
>>
>> Problem : the multi-hop packet is declared like that :
>>    typedef nx_struct mhpacket {
>>      mhpacket_header_t header;
>>      nx_uint8_t data[TOSH_DATA_LENGTH-sizeof(mhpacket_header_t)];
>>    } mhpacket_t;
>>
>> As a result, the Receiver class thinks the packet length is always
>> TOSH_DATA_LENGTH, and reports that received messages are too short.
>>
>> Isn't it possible to use variable-length packets ?
>>
>>
>> Thanks for your help,
>>
>> Romain
>>
>
> Nevermind, I changed the declaration to :
>
>   typedef nx_struct mhpacket {
>     mhpacket_header_t header;
>     nx_uint8_t data[];
>   } mhpacket_t;
>
> and it seems to work fine.

That's the right solution.

Phil