Re: [Jack-Devel] OS X jack midi message issues between jack and core midi

Le 2 août 2012 à 21:40, Devin Anderson a écrit :

> On Mon, Jul 16, 2012 at 12:00 AM, Stéphane Letz <[hidden]> wrote:
> 
>> JackOSX indeed uses jack2, but building the whole stuff is a bit of
>> pain... I'll try to do that and prepare a new package this week.
> 
> I got around to looking at the JACK 2 code on github.com/jackaudio,
> and I don't see the fix applied for duplicate messages that I sent
> over.  I think the fix should be applied.

The patch has been applied on my private tree and is part of latest JackOSX package, but it does not seem to fix the issue.
> 
> As far as dropped messages go, I noticed that the ProcessRead() and
> ProcessWrite() calls in JackCoreMidiDriver now have TryLock() calls:
> 
>    int
>    JackCoreMidiDriver::ProcessRead()
>    {
>        int res;
>        if (Trylock()) {
>            res = (fEngineControl->fSyncMode) ? ProcessReadSync() :
> ProcessReadAsync();
>            Unlock();
>        } else {
>            res = -1;
>        }
>        return res;
>    }
> 
>    int
>    JackCoreMidiDriver::ProcessWrite()
>    {
>        int res;
>        if (Trylock()) {
>            res = (fEngineControl->fSyncMode) ? ProcessWriteSync() :
> ProcessWriteAsync();
>            Unlock();
>        } else {
>            res = -1;
>        }
>        return res;
>    }
> 
> Could this be the reason for the dropped messages?

This lock was added to avoid race when the CoreMIDI setup is dynamically changed, causing the JackCoreMidiDriver::Restart function to be called. It is not happening in this specific case.

So the issue still seems there...

Stephane 

1343940887.24252_0.ltw:2,a <9CEAF81F-C954-4CE0-A9B0-5C7BD8233227 at grame dot fr>