====== Sound mixer improvements ======

  * Student: [[/ChristosMargiolis|ChristosMargiolis]] (christos@)
  * Mentor:  [[/HansPetterSelasky|HansPetterSelasky]] (hselasky@)

===== Project description =====

%%FreeBSD%%'s default mixer utilities are not the best; ''%%mixer(8)%%'' is very basic
and outdated, end users have to tweak ''%%sysctl(8)%%'' values to do simple things and
programmers have to write DIY implementations for their programs
(e.g ''%%audio/mixertui%%''). This project aims to improve mixer handling for OSS on
%%FreeBSD%% and make life for both programmers and users easier.

===== Deliverables =====

  * A ''%%mixer(3)%%'' library.
    * Read all devices and knobs.
    * Extend knob capabilities:
      * 32-bit floating point left-right volume knobs.
      * Muting.
      * Recording input selector.
    * Select default sound card (not really a mixer feature, but really useful to have).
    * Provide as much information as possible about the mixer.
    * Use the more modern OSSv4's ioctls.
  * Rewrite ''%%mixer(8)%%''.
    * Use ''%%mixer(3)%%'' and its new features.
    * Get rid of the old codebase completely.
    * Add more command line options.
    * Control-oriented interface like in ''%%sysctl(8)%%''.
  * Implement some missing but useful for ''%%mixer(3)%%'' OSS ioctls in the kernel.
  * Implement sound device playback/recording status ''%%sysctl%%''.
  * Update ''%%/etc/rc.d/mixer%%'' to work with the new version of ''%%mixer(8)%%''.
  * Make ''%%/dev/sndstat%%'' "useless" by containing its information in the output of ''%%mixer(8)%%''.

===== What didn't get done =====

  * Panning capabilities in mixer(3), but it should be easy to write a DIY handler using the ''%%mix_ctl_t%%'' interface.

===== Test plan =====

Since a new version of ''%%mixer(8)%%'' is one of the delievarables, it'll also serve
as a testing ground for the library. Me and the mentor will also test the library
with various sound devices we own.

===== Weekly progress =====

^  Email archive  ^
| [[https://lists.freebsd.org/pipermail/soc-status/2021-June/001262.html|Week 1]] |
| [[https://lists.freebsd.org/pipermail/soc-status/2021-June/001264.html|Week 2]] |
| [[https://lists.freebsd.org/pipermail/soc-status/2021-June/001265.html|Week 3]] |
| [[https://lists.freebsd.org/pipermail/soc-status/2021-July/001267.html|Week 4]] |
| [[https://lists.freebsd.org/pipermail/soc-status/2021-July/001269.html|Week 5]] |
| [[https://lists.freebsd.org/pipermail/soc-status/2021-July/001270.html|Week 6]] |
| Week 7 (Vacation) |
| [[https://lists.freebsd.org/archives/soc-status/2021-August/000001.html|Week 8]] |
| [[https://lists.freebsd.org/archives/soc-status/2021-August/000002.html|Week 9]] |
| [[https://lists.freebsd.org/archives/soc-status/2021-August/000003.html|Week 10]] |

===== The code =====

  * [[https://github.com/christosmarg/mixer|GitHub]]
  * [[https://git.sr.ht/~crm/mixer|Sourcehut]]
  * [[https://git.margiolis.net/mixer/files.html|My own Git server]]

===== Documentation =====

  * [[https://www.freebsd.org/cgi/man.cgi?query=mixer&apropos=0&sektion=3&manpath=FreeBSD+14.0-current&arch=default&format=html|mixer(3)]]
  * [[https://www.freebsd.org/cgi/man.cgi?query=mixer&apropos=0&sektion=8&manpath=FreeBSD+14.0-current&arch=default&format=html|mixer(8)]]

===== Code reviews =====

  * [[https://reviews.freebsd.org/D31130|sound(4) mute ioctls implementation]] ([[https://cgit.freebsd.org/src/commit/?id=0f8dafb45859569aa36b63ca2bb4a1c35c970d1e|merged]])
  * [[https://reviews.freebsd.org/D31320|sound(4) playback/recording mode sysctl implementation]] ([[https://cgit.freebsd.org/src/commit/?id=ed2196e5df0c8b5b81563d2fffdcb32bb7ebe966|merged]])
  * [[https://reviews.freebsd.org/D31636|Final project review]] ([[https://cgit.freebsd.org/src/commit/?id=903873ce15600fc02a0ea42cbf888cff232b411d|merged]])

===== Useful links =====

  * [[http://manuals.opensound.com/developer/|OSS 4.x Programmer's Guide]]
  * [[https://www.freebsd.org/cgi/man.cgi?query=sound&apropos=0&sektion=0&manpath=FreeBSD+13.0-RELEASE+and+Ports&arch=default&format=html|sound(4)]]
  * [[https://www.freebsd.org/cgi/man.cgi?query=sysctl&apropos=0&sektion=0&manpath=FreeBSD+13.0-RELEASE+and+Ports&arch=default&format=html|sysctl(8)]]
  * [[https://man.openbsd.org/mixerctl|mixerctl(8)]]

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{{tag>Gsoc}}