ASN.1 decoding problems with H.323

Bruce Fitzsimons <>
Tue May 22 01:49:45 CEST 2001


Hi Bertil, thanks for the reply

> Maybe is not my encoding values enough realistic?
Your example is fine. Thanks for the effort, I should have done the same in
my original email.

> I have not done any tests on an unpatched R7B. The version I have used
> includes an update of the ASN.1 compiler, which will be released as open
> source in about a week. If you have an Erlang licens it is available for
> download.

My version seems to encode okay, but the decode (using your values) fails in
the same way as documented in my previous mail:

()5>
asn1rt:decode('H323-MESSAGES','GatekeeperRequest',[8,43,102,2,42,3,0,17,13,1
9,20,21,179,1,0,1,6,0,3,69,103,137,171,193,32]).
{error,{function_clause,[{asn1rt_per_v1,getbit1,[{0,[]}]},
                         {asn1rt_per_v1,getbits,3},
                         {asn1rt_per_v1,chars_decode2,5},
                         {'H323-MESSAGES',dec_AliasAddress,2},
                         {'H323-MESSAGES',
                             dec_GatekeeperRequest_endpointAlias_components,
                             4},
                         {'H323-MESSAGES',dec_GatekeeperRequest,2},
                         {asn1rt,decode,3},
                         {erl_eval,expr,3}|
                         more]}}

So it seems the original R7B-2 decoder had some problems, and I'm going to
stop spelunking the code as its already been fixed :-)

> PS Is there any plans for a per_bin option?
> Yes, we are developing a version that uses the bit syntax. The plan is to
> include it in R8.

Great. More speed would be nice :-)

Thanks again for your response Bertil, at least I know that it can work - I
will be waiting anxiously for the next release.

Cheers,
Bruce





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