jack 0.4.0

Real time audio and midi using safe JACK bindings.
Documentation

Rust JACK

License: MIT

crates.io docs.rs

Build Status Coverage Status

Nice Rust bindings for JACK Audio Connection Kit

Documentation for Master

Check out the examples directory.

Completeness

For details on which functions from the JACK headers have been implemented, see ffi_completeness.md.

More high-level, creating clients, creating/reading/writing/connecting ports, audio, and midi are supported.

Missing categories include, JACK threading, synchronous processing, transport and control functionality.

Running

  • libjack is required. Consult your package manager or the official website.

  • The general workflow for a JACK application is to start up a JACK daemon and connect the client to it. qjackctl is a convinient way to configure and bring up a JACK server through a GUI.

  • JACK FAQ

Testing

Testing is a little awkward to setup since it relies on a JACK server.

Setting Up JACK Dummy Server

$ ./dummy_jack_server.sh

which runs the command

$ jackd -r -ddummy -r44100 -p1024 & # Start the dummy JACK server

Testing expects there to be an available JACK server running at a sample rate of 44.1kHz and a buffer size of 1024 samples.

Possible Issues

If the tests are failing, a possible gotcha may be timing issues.

  1. Rust runs tests in parallel, it may be possible that the JACK server is not keeping up. Set the environment variable RUST_TEST_THREADS to 1.
  2. Increase the value used by sleep_on_test.

Another case is that libjack may be broken on your setup. Try switching between libjack and libjack2 (they have the same API and libjack2 isn't necessarily newer than libjack), or using a different version.

Running the tests

$ RUST_TEST_THREADS=1
$ cargo test

"C" & Rust API differences

  • String lengths in the "C" API include the NULL character while these Rust bindings do not. generally rust_size(x) = c_size(x) - 1.
  • "C" bindings require functions to be registered while Rust bindings register an object with a trait.
  • jack_on_shutdown has been removed, uses only jack_on_info_shutdown.
  • Rust enums vs C enums
  • Rust bitflags vs C integers used as flags
  • deprecated JACK functions are not used/implemented in Rust bindings

C JACK API

Main Page