Mixer State in OpenSolaris

Posted on by

I’ve recently installed OpenSolaris on my desktop and noticed that my volume settings do not persist between reboots. A quick search revealed that that functionality hasn’t been implemented yet. The thread suggested using the mixerctl command to save and restore the mixer state so I’ve thrown together an SMF service to do it automatically on boot and shutdown.

First, the script which should go into /lib/svc/method/sound-mixer:

#!/sbin/sh

. /lib/svc/share/smf_include.sh
smf_is_globalzone || exit $SMF_EXIT_OK

ctl_file=$(svcprop -p options/ctl_file $SMF_FMRI)

case "$1" in
'start')
        if [ ! -f $ctl_file ]; then
                echo "Mixer control file $ctl_file does not exist."
                exit $SMF_EXIT_OK
        fi

        if ! /usr/sbin/mixerctl -r $ctl_file; then
                echo "Error restoring mixer state."
                exit $SMF_EXIT_OK
        fi
        ;;

'stop')
        if ! /usr/sbin/mixerctl -f -s $ctl_file; then
                echo "Error saving mixer state."
                exit $SMF_EXIT_OK
        fi
        ;;

*)
        echo "Usage: $0 { start | stop }"
        exit $SMF_EXIT_ERR_CONFIG
        ;;
esac

exit $SMF_EXIT_OK

Second, the manifest which can be saved anywhere and loaded with svccfg -v import <manifest>:

<?xml version="1.0"?>
<!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1">

<service_bundle type='manifest' name='mixer'>

<service
       name='system/sound/mixer'
       type='service'
       version='1'>

        <create_default_instance enabled='true' />
        <single_instance />

        <dependency
           name='fs-local'
           grouping='require_all'
           restart_on='none'
           type='service'>
                <service_fmri value='svc:/system/filesystem/local' />
        </dependency>
       
        <dependency
           name='device-audio'
           grouping='require_all'
           restart_on='none'
           type='service'>
                <service_fmri value='svc:/system/device/audio' />
        </dependency>

        <exec_method
               type='method'
               name='start'
               exec='/lib/svc/method/sound-mixer start'
               timeout_seconds='60' />

        <exec_method
               type='method'
               name='stop'
               exec='/lib/svc/method/sound-mixer stop'
               timeout_seconds='60' />

        <property_group name='options' type='application'>
                <propval name='ctl_file' type='astring' value='/etc/sound/mixer.state' />
        </property_group>

        <property_group name='startd' type='framework'>
                <propval name='duration' type='astring' value='transient' />
        </property_group>

        <stability value='Unstable' />

        <template>
                <common_name>
                        <loctext xml:lang='C'>Mixer State Saver</loctext>
                </common_name>
                <documentation>
                        <manpage title='mixerctl' section='1M'
                           manpath='/usr/share/man' />
                </documentation>
        </template>

</service>

</service_bundle>

UPDATE: In b130, the audioctl command replaces mixerctl. In the sound-mixer script above, change /usr/sbin/mixerctl -r $ctl_file to /usr/bin/audioctl load-controls $ctl_file and /usr/sbin/mixerctl -f -s $ctl_file to /usr/bin/audioctl save-controls -f $ctl_file.

One thought on “Mixer State in OpenSolaris”

Leave a Reply