FW: OM 2.4.1 and transport destroy also destroys mama_publisher
Apologies – originally sent this out on Monday but I think it may have been rejected from the mailing list due to not updating my subscription with my new Vela email address.
I don’t think we’ve seen this one – although perhaps others have, but you’re the first to report it. I’ll have to take more of a look at this, especially this –
>> Is the code for a transport to trigger publishers to destroy themselves sufficiently embedded that it could not be removed since existing apps depend on it?
I’m currently looking through this to confirm just how necessary this is. Also, this is a good point –
>> It’s probably reasonable to assume that if an app is destroying its transport that it will not destroy its publishers after that.
The transport should be the last object destroyed anyway, ie all other MAMA objects should be destroyed before it – but previously the fate of publishers probably didn’t matter that much.
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From: openmama-dev-bounces@... [mailto:openmama-dev-bounces@...] On Behalf Of Alpert, Reed via Openmama-dev
Sent: 07 July 2016 20:33
Subject: [Openmama-dev] OM 2.4.1 and transport destroy also destroys mama_publisher
Testing with OM 2.4.1.
If a C++/MamaPublisher is not destroyed before the C++/MamaTransport is destroyed, then the C/mamaTransport will notify each C/mamaPublisher that the transport is going away, and the mamaPublisher will call destroy on itself. This triggers the onDestroy callbacks, which vector up to the C++ layer, but the destroy was never called on the C++ object, creating a crash in the tear-down (in my case when the mamaPublisher tries to destroy its list for a 2nd time).
I think in OM 2.3 and before the absence of the onDestroy cb prevented this bug from occurring, but it still seems incorrect to destroy the C/mamaPublisher if there is a C++/MamaPublisher holding it. It’s probably reasonable to assume that if an app is destroying its transport that it will not destroy its publishers after that.
When destroying the MamaPublisher before the MamaTransport this does not occur since the mamaPublisher is removed from the transport.
Is the code for a transport to trigger publishers to destroy themselves sufficiently embedded that it could not be removed since existing apps depend on it?
Has anyone else seen this in testing?
Reed Alpert | Corporate & Investment Bank | Market Data Services | J.P. Morgan | 4 Metrotech Center, 23rd Floor, Brooklyn, NY 11245 | T: 718.242.5198 | M: 917.414.4613 | reed.alpert@...
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