Improvement #5577 : embedded: after fb_shutdown some files stay locked [CORE5299]

[hvlad]

No description provided.

[asfernandes]

This would be problematic for applications that uses ICU and FB-embedded.
Firebird may call cleanup of a library it didn't loaded.
ICU is used by many applications.
I think this should not be done.

[hvlad]

This would be problematic for applications that uses ICU and FB-embedded. Firebird may call cleanup of a library it didn't loaded.

Are you means the case when app already loaded ICU before engine does ?
Here I agree, u_cleanup() could be dangerous for the app.

We might "just unload" ICU libraries, not calling u_cleanup().
This will unload ICU libraries if there are no more references only and should be safe.
But all data files loaded by ICU (.dat and *.res) will remains in memory.

Maybe we could introduce some way to control this (to call u_cleanup() or not) ?

[hvlad]

One more question - how to handle the case when ICU is loaded multiply times by Firebird itself.
It could be loaded by the engine, the trace and even by the fbclient, AFAIU.

[asfernandes]

Are you means the case when app already loaded ICU before engine does ?

Yes, but the inverse may also be possible.

I see no safe way to have u_cleanup() called.

And if you unload without calling it, then there will be multiple memory leaks each time this is done.