DDS Unbounded IDL

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Last seen: 6 years 8 months ago
Joined: 08/02/2017
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DDS Unbounded IDL

Hi,

 

I am trying to create a message that will have a dynamic message header. The software I am modifying is from an old system and we are trying to prove we can use DDS on the system. The problem is when the message is passed down to the comm layer we are given a message with a dynmically sized header attached to it. I only care about the actual data, but the legacy code still needs the header so I need to pass it all over.  Is there a way to put a truely unbounded type in the IDL?

 

Thanks

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Last seen: 3 months 5 days ago
Joined: 02/11/2016
Posts: 144

Hey,

What makes the idl "unbounded"?

What makes the header "dynamically sized"?

If your problem is optional fields, RTI supports those (I believe in 5.2+ they are fully supported, in 5.1 You can implement them using sequences of maximum length 1 [or fields with agreed upon default null values]).

If your problem is bounded sequences, I believe 5.2 is supposed to fully support unbounded sequences.

Regarding strings I'm uncertain.

 

Hope this helps,

Roy.

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Last seen: 6 years 8 months ago
Joined: 08/02/2017
Posts: 2

Hey,

Thanks for responding. I have a very old piece of software that is written originally in Ada and it passes the message as a buffer to the C/C++ layer where the code creates a class and copies the message after the classes. The problem is the classes have mulitple inheritances and one of the classes inherited is a logging class where they have a few std::strings. 

I don't care about these headers, I just need to pass them so I was trying to figure out how to add a DDS_Oct_Seq to the front of the IDL I have but it can't be a fixed length since it is going to all depend on the string size they are going to pass.

I have read that RTI supports having a variable size sequence, I just haven't found a good example anywhere. 

 

Thanks

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Last seen: 3 months 5 days ago
Joined: 02/11/2016
Posts: 144

Hey,

A quick google search (unbounded sequences rti) comes up with the following:
https://blogs.rti.com/2015/08/26/unbounded-support-for-sequences-and-strings/

I will point out that according to the link, integration of unbounded sequences with persistence and db integration service is not currently supported.

Good luck,
Roy.