portage-tmpfs

#!/sbin/openrc-run
# nic@boet.cc
# init script to populate tmpfs mounted portage repo
#

extra_started_commands="snapshot"
extra_stopped_commands="setup remove"

portage="/var/db/repos"
tar=/var/db/repos-snapshot.tar.gz

depend() {
    before nfs
}

snapshot() {
    if [ -f ${tar} ]; then
        if test `find ${tar} -mmin -1440` ; then
            einfo "   skipping snapshot creation, recent archive exists"
            return 0
        fi
    fi

    if [ -f ${portage}/tmpfs-not-mounted ] ; then
        eerror "   refusing to create snapshot, ${portage}/tmpfs-not-mounted exists"
        return 1
    fi

    einfo "   creating portage snapshot"
    tar -czp --absolute-names ${portage} -f ${tar} > /dev/null 2>&1 || return 1
    
    return 0
}

restore(){
    einfo "   restoring ${tar} to ${portage}"
    tar -xzf ${tar} ${portage} -C / > /dev/null  2>&1 || return 1

    return 0
}

setup() {
    ebegin "Deploying ${SVCNAME}"

    if grep "${portage}" /etc/fstab > /dev/null; then
        ewarn "   already setup, ${portage} defined in /etc/fstab"
        return 1
    fi

    if [ -f ${portage}/tmpfs-not-mounted ] ; then
        ewarn "   already setup, ${portage}/tmpfs-not-mounted exists"
        return 1
    fi

    if mountpoint ${portage} > /dev/null; then
        eerror "   mountpoint already exists at ${portage}"
        return 1
    fi

    if [ ! -f ${portage}/gentoo/metadata/timestamp ] ; then
        eerror "   existing gentoo repo not found under ${portage}"
        return 1
    fi

    snapshot || return 1

    einfo "   purging ${portage}"
    rm -r ${portage} || return 1
    mkdir ${portage} || return 1

    einfo "   creating mountpoint"
    touch $portage/tmpfs-not-mounted || return 1
    echo "none  /var/db/repos/  tmpfs   defaults,size=2G    0 0  ## ${SVCNAME} ##" >> /etc/fstab || return 1

    einfo "setup complete, please start service"

    eend $?
}

remove() {
    ebegin "Removing ${SVCNAME}"

    if mountpoint ${portage} > /dev/null; then
        umount -fl ${portage} > /dev/null || return 1

        if mountpoint ${portage} > /dev/null ; then
            eerror "   env not stable, ${portage} still mounted"
            return 1
        fi
    fi

    if [ -f ${portage}/tmpfs-not-mounted ] ; then
        rm ${portage}/tmpfs-not-mounted || return 1
    fi

    if grep "${portage}" /etc/fstab > /dev/null; then
        sed -i "/## ${SVCNAME} ##/d" /etc/fstab || return 1
    fi

    einfo "   purging ${portage}"
    rm -r ${portage} || return 1
    mkdir ${portage} || return 1

    restore || return 1

    if [ -f ${tar} ] ; then
        rm $tar || return 1
    fi
    
    einfo "complete"
    eend $?
}

start() {
    ebegin "Starting ${SVCNAME}"
    if mountpoint ${portage} > /dev/null ; then
        ewarn "   unmounting ${portage}"
        umount -fl ${portage} > /dev/null || eerror "   failed"
    fi

    if [ ! -f ${portage}/tmpfs-not-mounted ] ; then
        eerror "   please run setup first"
        return 1
    fi
    
    mount ${portage} > /dev/null || eerror "   failed to mount ${portage}"

    if [ ! -f ${portage}/gentoo/metadata/timestamp ] ; then
        restore || eerror "   failed to restore ${tar}"
    fi

    eend $?
}

stop() {
    ebegin "Stopping ${SVCNAME}"
  
    if mountpoint ${portage} > /dev/null ; then
        if [ -f ${portage}/gentoo/metadata/timestamp ] ; then
            snapshot || eerror "   failed to archive current tmpfs contents"
        fi
        umount -fl ${portage} > /dev/null || ewarn "   failed to umount tmpfs"
    else
        ewarn "   openrc-run started state, ${portage} not mounted"
    fi

    eend $?
}