git: 100a9852dd89 - main - audio/jack: Remove obsolete realtime hack for RC service, with checks

From: Yuri Victorovich <yuri_at_FreeBSD.org>
Date: Sun, 11 Feb 2024 17:04:49 UTC
The branch main has been updated by yuri:

URL: https://cgit.FreeBSD.org/ports/commit/?id=100a9852dd8957a1d7a337858a3319da693915c9

commit 100a9852dd8957a1d7a337858a3319da693915c9
Author:     Florian Walpen <dev@submerge.ch>
AuthorDate: 2024-02-11 17:03:42 +0000
Commit:     Yuri Victorovich <yuri@FreeBSD.org>
CommitDate: 2024-02-11 17:03:42 +0000

    audio/jack: Remove obsolete realtime hack for RC service, with checks
    
    PR:             276607
---
 audio/jack/Makefile       |  2 +-
 audio/jack/files/jackd.in | 43 ++++++++++++++++++++++++++++++++++++-------
 audio/jack/pkg-message    | 11 +++++++----
 3 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/audio/jack/Makefile b/audio/jack/Makefile
index 49efc4daf81a..f8eeea1cf31e 100644
--- a/audio/jack/Makefile
+++ b/audio/jack/Makefile
@@ -1,7 +1,7 @@
 PORTNAME=	jackit
 DISTVERSIONPREFIX=	v
 DISTVERSION=	1.9.22
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	audio
 
 MAINTAINER=	dev@submerge.ch
diff --git a/audio/jack/files/jackd.in b/audio/jack/files/jackd.in
index 9f135a6c8f1b..e78285044ea7 100644
--- a/audio/jack/files/jackd.in
+++ b/audio/jack/files/jackd.in
@@ -11,7 +11,7 @@
 : ${jackd_enable="NO"}
 : ${jackd_user="root"}
 : ${jackd_rtprio="NO"}
-: ${jackd_args="-r -doss -r44100 -p1024 -n3 -w16"}
+: ${jackd_args="--no-realtime -doss -r48000 -p1024 -w32"}
 
 . /etc/rc.subr
 
@@ -20,15 +20,44 @@ rcvar=jackd_enable
 procname=%%PREFIX%%/bin/jackd
 start_cmd="start_jackd"
 
+fail() {
+  echo "JACK failed to start: $1" >&2
+  exit 1
+}
+
+check_config() {
+  # check that jackd_user is set
+  if [ -z "$jackd_user" ]; then
+    fail "jackd_user has to be defined"
+  fi
+
+  # detect intent to use realtime priority
+  if [ "$jackd_rtprio" = "YES" ] || \
+     { echo "$jackd_args" | grep -q -- "oss" && \
+       { echo "$jackd_args" | grep -qw -- "--realtime"  || \
+         echo "$jackd_args" | grep -qw -- "-[A-Za-mo-z]*R[A-Za-z]*"; }; }; then
+    # check that mac_priority(4) is enabled
+    if [ "$(sysctl -qn security.mac.priority.realtime)" != "1" ]; then
+      fail "Realtime priority requires mac_priority(4) to be loaded"
+    fi
+    # check that the user has realtime privileges
+    if ! (su -m "$jackd_user" -c "rtprio 10 test -z"); then
+      fail "User jackd_user=$jackd_user is not a member of the realtime group"
+    fi
+  fi
+}
+
 start_jackd() {
   echo "Starting ${name}."
-  if [ $jackd_rtprio = "YES" ]; then
-    local rt="rtprio 1"
-  fi
+
+  # check that setup is valid
+  check_config
+
   # log the date and parameters
-  echo -e "\n[`date`] Starting the daemon, user=$jackd_user rtprio=$jackd_rtprio args=\"$jackd_args\"" >> /var/log/${name}.log
-  # daemon(8) should be able to set the realtime priority, but it isn't
-  $rt daemon -p /var/run/${name}.pid -u "${jackd_user}" %%PREFIX%%/bin/jackd ${jackd_args}
+  echo -e "\n[`date`] Starting the daemon, user=$jackd_user args=\"$jackd_args\"" >> /var/log/${name}.log
+
+  # start the daemon
+  daemon -p /var/run/${name}.pid -u "$jackd_user" %%PREFIX%%/bin/jackd $jackd_args
 }
 
 load_rc_config ${name}
diff --git a/audio/jack/pkg-message b/audio/jack/pkg-message
index 2a94946d2d57..6ab2e5764e59 100644
--- a/audio/jack/pkg-message
+++ b/audio/jack/pkg-message
@@ -3,11 +3,15 @@ The new JACK server comes with a DBUS control interface:
 $ jack_control help
 $ jack_control ds oss
 $ jack_control dp
+$ jack_control dps rate 48000
+$ jack_control dps wordlength 16
+$ jack_control dps capture /dev/dsp0
+$ jack_control dps playback /dev/dsp0
 $ jack_control eps realtime False
 $ jack_control start
 
-Only root can grant real-time priority to processes for now, using rtprio(1).
-Upcoming FreeBSD releases will have a MAC policy with a realtime user group.
+To use real-time priority for JACK server and clients, load the mac_priority(4)
+module and add the JACK user to the realtime group.
 
 Memory locking has to be allowed in /etc/login.conf or ~/.login_conf. Set the
 resource limit ":memorylocked=unlimited:" and don't forget to run
@@ -19,8 +23,7 @@ Note that only one JACK server can be run at a time. An /etc/rc.conf example:
 
 jackd_enable="YES"
 jackd_user="joe"
-jackd_rtprio="YES"
-jackd_args="-R -doss -r48000 -p1024 -n1 -w16 \
+jackd_args="--no-realtime -doss -r48000 -p1024 -w16 \
             --capture /dev/dsp0 --playback /dev/dsp0"
 
 Official JACK example clients and tools are available as jack-example-tools.