zfs.subr

#v10.0.0
# return 0 if $1 is not valid ZFS mountpoint
# return 1 if $1 is valid ZFS mountpoint and mounted
# return 2 if $1 is valid ZFS mountpoint and not mounted
# if  zfsmnt /mnt; then
#    echo " not zfs (mounted or not) mountpoint"
# fi
# export ZPOOL for name ZFS for $1 mountpoint
zfsmnt() {
    local _A

    ZPOOL=$(zfs list -Ho name,mountpoint | while read _name _mnt; do
	[ "${_mnt}" = "${1}" ] && echo ${_name} && exit 2
    done)

    if [ $? -eq 2 ]; then
	#    Check for mounted
	_A=`zfs get -Ho value mounted ${ZPOOL}`
	[ "${_A}" = "yes" ] && return 1
	return 2
    else
	return 0
    fi
}

# return 0 if $1 is not valid ZFS filesystem
# return 1 if $1 is valid ZFS mountpoint and mounted
# return 2 if $1 is valid ZFS mountpoint and not mounted
# if  zfsfs /mnt; then
#    echo " not zfs (mounted or not) mounted"
# fi
zfsfs() {
    local _A

    _A=$(zfs list -Ho name | while read _name; do
	[ "${_name}" = "${1}" ] && exit 2
    done)

    if [ $? -eq 2 ]; then
	#    Check for mounted
	_A=`zfs get -Ho value mounted ${1}`
	[ "${_A}" = "yes" ] && return 1
	return 2
    else
	return 0
    fi
}

# export zmnt if $zroot exist, return 1
getmnt() {
    local _res

    [ -z "$1" ] && return 1
    zmnt=`zfs get -Ho value mountpoint ${1}`
    return $?
}

# return 0 if ${ZPOOL}/$1 zfs source exist
# if zfsroot jail1; then
# echo "zroot/$jail1 exist
# fi
zfsroot() {
    [ -z "$1" ] && return 0

    zfs list -H -o name | while read _mnt; do
	[ "$_mnt" = "${ZPOOL}/${1}" ] && exit 0
    done

    return $?
}