Arch Linux

> and is reported as working well in qemu 5.1.0

could you please provide links with the user's feedback?

Here's a link to the developer's thread that includes his testing and experience and other users feedback
https://forum.level1techs.com/t/qemu-native-jack-audio-support/156494

Thank you for the link. The request sounds reasonable to me.

Could you please check if the patch below works for you? If yes then I will move with adding the feature to the official package.


```
Index: PKGBUILD
===================================================================
--- PKGBUILD (revision 397386)
+++ PKGBUILD (working copy)
@@ -13,7 +13,7 @@
_headlessdeps=(seabios gnutls libpng libaio numactl libnfs
lzo snappy curl vde2 libcap-ng spice libcacard usbredir libslirp
libssh zstd liburing)
-depends=(virglrenderer sdl2 vte3 libpulse brltty "${_headlessdeps[@]}")
+depends=(virglrenderer sdl2 vte3 libpulse jack brltty "${_headlessdeps[@]}")
makedepends=(spice-protocol python ceph libiscsi glusterfs python-sphinx xfsprogs)
source=(https://download.qemu.org/qemu-$pkgver.tar.xz{,.sig}
qemu-ga.service
@@ -36,7 +36,7 @@

build() {
_build full \
- --audio-drv-list="pa alsa sdl"
+ --audio-drv-list="pa alsa sdl jack"

_build headless \
--audio-drv-list= \
```

Slightly off-topic. I see that QEMU has "spice" audio driver as well. Is it something useful for Arch user?

Below is my patch.
1. You need to increase pkgrel to get current 5.1.0 installs updated.
2. You should really use jack2 instead of jack. jack is now in bugfix only mode and most users install and use jack2.

===================>8========================

--- ./PKGBUILD.o 2020-08-03 09:02:06.137695904 -0400
+++ PKGBUILD 2020-08-03 09:04:43.242426008 -0400
@@ -6,14 +6,14 @@
qemu-block-{iscsi,rbd,gluster} qemu-guest-agent)
pkgdesc="A generic and open source machine emulator and virtualizer"
pkgver=5.1.0
-pkgrel=1
+pkgrel=2
arch=(x86_64)
license=(GPL2 LGPL2.1)
url="https://wiki.qemu.org/"
_headlessdeps=(seabios gnutls libpng libaio numactl libnfs
lzo snappy curl vde2 libcap-ng spice libcacard usbredir libslirp
libssh zstd liburing)
-depends=(virglrenderer sdl2 vte3 libpulse brltty "${_headlessdeps[@]}")
+depends=(virglrenderer sdl2 vte3 libpulse jack2 brltty "${_headlessdeps[@]}")
makedepends=(spice-protocol python ceph libiscsi glusterfs python-sphinx xfsprogs)
source=(https://download.qemu.org/qemu-$pkgver.tar.xz{,.sig}
qemu-ga.service
@@ -36,7 +36,7 @@

build() {
_build full \
- --audio-drv-list="pa alsa sdl"
+ --audio-drv-list="pa alsa sdl jack"

_build headless \
--audio-drv-list= \

The drivers you specify in the "--audio-drv-list" are backend drivers (drivers that work on the hypervisor/host side, not the guest). The spice backend driver is used in rare cases where you need to connect hypervisors over spice. I never used it and don't believe it is necessary for most users.

"jack2" package provides "jack". You can install jack2 and use it here.

So it is ok to specify "jack" here. It is what all the packages in Arch repo do.

You are correct. both jack and jack2 are protocol interchangeable and it's ok to specify jack

@anatolik: If you add jack support, please also add `libjack.so` (as this is most likely what qemu will link against - if in doubt, check with `find-libdeps`) to depends in package().

libjack.so is not an Arch package. It is provided by the "jack" package which is now going to be a dependency of qemu.

My question is "why to use libjack.so as a dependency instead of just 'jack'"?

@Netboy3: The libprovides [1] are specifically added for the purpose for being able to tie dependants [2] to specific versions of a shared object and are part of the Arch packaging guidelines.

@anatolik: It guards against soname bumps as makepkg automatically includes the shared object version.
However, currently the only way (IMHO) to only have e.g. libjack.so in depends, jack needs to be added to makedepends and libjack.so added to depends in package() as there makepkg will have been able to have figured out the shared object version.
The sodep can also be added right after the package providing it (e.g. `depends=('jack' 'libjack.so')`), with the "downside" that both are then in depends.

[1] https://wiki.archlinux.org/index.php/Arch_package_guidelines#Package_relations
[2] https://wiki.archlinux.org/index.php/Arch_package_guidelines#Package_dependencies

Alright, I enabled JACK in SVN revision 397454. It will be available to the users with the next package build (e.g. 5.1.1 or 5.1.0-2).