Re: [fluid-dev] Jack Driver for Fluidsynth Windows Build

[Stéphane Letz]

Le 18 avr. 2011 à 08:47, David Henningsson a écrit :

> Hi Graham,
> 
> I don't want to push the problem back and forward, but in this case I think 
> it's reasonable to say that:
> 
> 1) We need to be told by the Jack devs about recommended way to link to the 
> jack headers.
> Does that means dynamic linking?

I guess you mean "weak linking" right? (that is the fact that fluidsynth can 
start even if libjack is not found...)

> On windows only or on all platforms? Will that still work with e g Jack 1? 
> Anyway, if we conclude dynamic linking is the way forward, it is reasonable 
> to think that there should be a version of JackWeakAPI.cpp that is in C and 
> not C++ (just like the rest of FS).
> I don't exactly know how difficult it would be to bring C++ code into FS on 
> all platforms, but it would probably be more difficult than rewriting 
> JackWeakAPI.cpp in pure C.
> 

Well I think the code in JackWeakAPI.cpp is completely C.... so the file can 
probably be safely used in C. I'll check again.

Concerning weak linking itself: the thing is that on jack now use (or tries to 
use...) __attribute__((__weak__)) kind of stuff from GCC, see:

http://trac.jackaudio.org/browser/jack2/trunk/jackmp/common/jack/weakjack.h

but the problem is that  I could not make this work on Windows which uses  
__declspec(dllexport) stuff to export symbols from the DLL. So on Windows the 
"compile JackWeakAPI.cpp" is the way to go. On OSX or Linux the more standard 
way (describe in weakjack.h) can be used.

> 
> 2) If Jack has an ASIO backend, that's great news! However, looking at
> http://trac.jackaudio.org/browser/jack2/trunk/jackmp/windows/JackRouter/JackRouter.h
> it seems to be declared under GPLv2+. I don't see how the end result could be 
> legally distributed in binary form, when the ASIO headers cannot be freely 
> distributed.
> 
> // David
> 
OK, but the ASIO headers  are only included to compile JackRouter. What would 
be the appropriate licence to be able to distribute binaries of JackRouter?

Stéphane