Control pulseaudio volume

volume.sh

#!/bin/bash

#=================
# commands:
#   volume           : get volume
#   volume [0,100]   : set volume, unmute
#   volume [up|down] : step volume up or down by small pct, unmute
#   volume mute      : toggle mute
#   volume muted     : exit 0/print true if muted, else exit 0/print false
#=================

SINK_NAME=$(pacmd dump | mawk '/set-default-sink/ {print $2}')
MUTED=$(pacmd dump | mawk '/set-sink-mute/ {print $3}')
# Everything in decimal
VOL_MAX=$((16#10000))
VOL_MIN=$((16#00000))
VOL_STEP=5

function constrain() {
    v=$1
    v=$(($v<$2?$2:$v))
    v=$(($v>$3?$3:$v))
    echo $v
}

function to_pct() {
    echo "scale=2;100 * ($(($1)) - $VOL_MIN) / ($VOL_MAX - $VOL_MIN) + 0.5;scale=0;last/1" | bc | sed -n 2p
}

function from_pct() {
    echo "scale=2;$1 * ($VOL_MAX - $VOL_MIN) / 100 + $VOL_MIN + 0.5;scale=0;last/1" | bc | sed -n 2p
}

function set() {
    if [ $MUTED = yes ]; then
        mute
    fi
    VOL_NEW=$(from_pct $1)
    pactl set-sink-volume $SINK_NAME $(printf "0x%X" $VOL_NEW)
    get
}

function get() {
    VOL_NOW=$(($(pacmd dump | mawk '/set-sink-volume/ {print $3}')))
    echo $(to_pct $VOL_NOW)
}

function up() {
    set $(( $(get) + VOL_STEP))
}

function down() {
    set $(( $(get) - VOL_STEP))
}

function mute() {
    if [ $MUTED = yes ]; then
        pactl set-sink-mute $SINK_NAME 0
    else
        pactl set-sink-mute $SINK_NAME 1
        get
    fi
}

function muted() {
    if [ $MUTED = yes ]; then
        echo true
        true
    else
        echo false
        false
    fi
}

case "$1" in
    up)   up;;
    down) down;;
    mute) mute;;
    muted) muted;;
    "")   get;;
    *)
        if [ "$1" -eq "$1" ] 2>/dev/null; then
          set $1
        else
          echo Invalid value [0,100]
          exit 1
        fi
    ;;
esac