Olivier Guilyardi: > > Ken Restivo wrote: >> It has been over 7 years since I last messed around with writing Pthreads applications. >> >> I recall it as a painful, ugly, brain-numbing task. I located an exercise I did back then to address the consumer/producer problem in Pthreads, and just the sight of it is giving me a headache. >> >> I'm being lazy, so instead of researching everything that's out there, I'll ask here: can anyone recommend a relatively simple and painless abstraction library (GPL or LGPL of course) that will give me functions to create a thread in which I can stuff things into a ring buffer, and another thread in which I can pull stuff out of it? >> >> By the way, I know that JACK has a very nice event buffer which is insanely easy to use (and I have), and makes multithreading almost transparent, but this isn't a JACK app. > > I don't know of any abstraction library, but creating/terminating a normal > thread with pthread is really an easy task IMO. It's about 10 lines in C. > > For inter-thread communication there's Portaudio's ring buffer: > http://portaudio.com/trac/browser/portaudio/trunk/src/common/pa_ringbuffer.h > > It can easily be used out of Portaudio (I'm currently doing that), and it > features memory barriers [1] which AFAIK Jack's ringbuffer doesn't. > > One problem with everything Portaudio is this heavy naming scheme. For a simpler > API, you might like my little wrapper: > http://jackbeat.samalyse.org/browser/jackbeat/trunk/src/core/ringbuffer.h > Nice. It's probably quicker to copy the jack_ringbuffer.c file out of jack though. > Portaudio actually also offers a callback mechanism (with hidden thread > creation), so if you're coding an non-JACK audio app, you might want to check it > out. > > For thread synchronization, semaphores (man semaphore.h) are really easy to use. > However, if you need a lock-free equivalent (for realtime, ...) phtread mutex > and especially pthread_mutex_trylock are your friends. > Those friends can be really cranky sometimes though. By using atomic operations instead, it's possible to avoid a lot of headache by not having to synchronize at all. Performance might be better too. Midishare has lockfree atomic functions for lifo and fifi queues: http://midishare.cvs.sourceforge.net/viewvc/midishare/midishare/src/common/atomic/ _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
