convert-albums

#!/bin/sh

usage()
{
    cat >&2 <<__EOF__
Usage: $(basename $0) [ -j numjobs ] [ album-dir ]

Options:
  -j numjobs    -- Maximum number of conversion processes that will be run
                   concurrently. Must be 1 or larger. Defaults to the number
                   of CPUs installed.
  album-dir     -- Name of the target directory. Defaults to
                   ${HOME}/media/music/classical.
__EOF__
    exit ${1-1}
}

log()
{
    echo "$(basename $0): $1" >&2
}

trap 'log "cleaning up.."; wait ; exit 0' SIGHUP SIGINT SIGTERM

while [ $# -gt 0 ]; do
    case $1 in
    -h|--help)
        usage 0
        ;;
    -j)
        shift; jobs="$1"
        ;;
    *)
        break
        ;;
    esac
    shift
done

: ${jobs=$(sysctl -n hw.ncpu)}

if [ $# -eq 1 ]; then
    albumdir="$1"
elif [ $# -eq 0 ]; then
    albumdir=${HOME}/media/music/classical
else
    usage
fi

if ! which -s oggenc; then
    log "oggenc isn't installed, exiting"
    exit 1
elif ! mount | awk '{print $1}' | egrep -q '^procfs$'; then
    log "procfs isn't mounted, exiting"
    exit 1
fi

[ ${#jobs} -gt 0 -a $(expr "$jobs" : [1-9][0-9]*) -eq ${#jobs} ] || usage

if ! cd "$albumdir" >/dev/null 2>&1; then
    log "couldn't cd to $albumdir"
    exit 1
fi
count=$(find . -name '*.flac' | wc -l | awk '{print $1}')
nproc=0
n=0

OLDIFS=$IFS
IFS='
'
for file in $(find . -name '*.flac'); do
    basefile=$(basename "${file%.flac}")
    basedir=${file%/flac/*.flac}
    n=$((n + 1))

    # Check to see if a converted version already exists.
    if [ -f "${basedir}/ogg/${basefile}.ogg" -o -f "${basedir}/flac/${basefile}.ogg" ]; then
        log "($n of $count) skipping $file"
        continue
    fi

    log "($n of $count) converting $file"
    oggenc -b 160 $file >/dev/null 2>&1 &
    pid=$! # PID of oggenc

    pidq="$pidq $pid"
    nproc=$((nproc + 1))

    while [ $nproc -ge $jobs ]; do
        sleep 1

        unset tpidq
        IFS=$OLDIFS
        for pid in ${pidq}; do
            piddir=/proc/$pid
            status=${piddir}/status
            if [ -d $piddir -a -r $status -a "$(awk '{print $3}' $status 2>/dev/null)" = $$ ]; then
                tpidq="$tpidq $pid"
            else
                # The oggenc run finished, so remove the PID.
                nproc=$((nproc - 1))
            fi
        done
        OLDIFS=$IFS
        IFS='
'
        pidq=$tpidq
    done
done

wait

for file in $(find . -name '*.flac'); do
    basefile=$(basename ${file%.flac})
    basedir=${file%/flac/*.flac}

    if [ ! -d "${basedir}/ogg" ]; then
        log "${basedir}/ogg doesn't exist - creating"
        mkdir "${basedir}/ogg"
    fi

    if [ -f ${basedir}/flac/${basefile}.ogg ]; then
        mv -f "${basedir}/flac/${basefile}.ogg" "${basedir}/ogg/${basefile}.ogg"
    fi
done

exit 0