#!/bin/sh
#
# rbd_mirror_helpers.sh - shared rbd-mirror daemon helper functions
#
# The scripts starts two ("local" and "remote") clusters using mstart.sh script,
# creates a temporary directory, used for cluster configs, daemon logs, admin
# socket, temporary files, and launches rbd-mirror daemon.
#
# There are several env variables useful when troubleshooting a test failure:
#
#  RBD_MIRROR_NOCLEANUP - if not empty, don't run the cleanup (stop processes,
#                         destroy the clusters and remove the temp directory)
#                         on exit, so it is possible to check the test state
#                         after failure.
#  RBD_MIRROR_TEMDIR    - use this path when creating the temporary directory
#                         (should not exist) instead of running mktemp(1).
#  RBD_MIRROR_ARGS      - use this to pass additional arguments to started
#                         rbd-mirror daemons.
#  RBD_MIRROR_VARGS     - use this to pass additional arguments to vstart.sh
#                         when starting clusters.
#
# The cleanup can be done as a separate step, running the script with
# `cleanup ${RBD_MIRROR_TEMDIR}' arguments.
#
# Note, as other workunits tests, rbd_mirror.sh expects to find ceph binaries
# in PATH.
#
# Thus a typical troubleshooting session:
#
# From Ceph src dir (CEPH_SRC_PATH), start the test in NOCLEANUP mode and with
# TEMPDIR pointing to a known location:
#
#   cd $CEPH_SRC_PATH
#   PATH=$CEPH_SRC_PATH:$PATH
#   RBD_MIRROR_NOCLEANUP=1 RBD_MIRROR_TEMDIR=/tmp/tmp.rbd_mirror \
#     ../qa/workunits/rbd/rbd_mirror.sh
#
# After the test failure cd to TEMPDIR and check the current state:
#
#   cd /tmp/tmp.rbd_mirror
#   ls
#   less rbd-mirror.cluster1_daemon.$pid.log
#   ceph --cluster cluster1 -s
#   ceph --cluster cluster1 -s
#   rbd --cluster cluster2 -p mirror ls
#   rbd --cluster cluster2 -p mirror journal status --image test
#   ceph --admin-daemon rbd-mirror.cluster1_daemon.cluster1.$pid.asok help
#   ...
#
# Also you can execute commands (functions) from the script:
#
#   cd $CEPH_SRC_PATH
#   export RBD_MIRROR_TEMDIR=/tmp/tmp.rbd_mirror
#   ../qa/workunits/rbd/rbd_mirror.sh status
#   ../qa/workunits/rbd/rbd_mirror.sh stop_mirror cluster1
#   ../qa/workunits/rbd/rbd_mirror.sh start_mirror cluster2
#   ../qa/workunits/rbd/rbd_mirror.sh flush cluster2
#   ...
#
# Eventually, run the cleanup:
#
#   cd $CEPH_SRC_PATH
#   RBD_MIRROR_TEMDIR=/tmp/tmp.rbd_mirror \
#     ../qa/workunits/rbd/rbd_mirror.sh cleanup
#

CLUSTER1=cluster1
CLUSTER2=cluster2
POOL=mirror
PARENT_POOL=mirror_parent
TEMPDIR=
USER_ID=mirror
export CEPH_ARGS="--id ${USER_ID}"

CEPH_ROOT=$(readlink -f $(dirname $0)/../../../src)
CEPH_BIN=.
CEPH_SRC=.
if [ -e CMakeCache.txt ]; then
    CEPH_SRC=${CEPH_ROOT}
    CEPH_ROOT=${PWD}
    CEPH_BIN=./bin

    # needed for ceph CLI under cmake
    export LD_LIBRARY_PATH=${CEPH_ROOT}/lib:${LD_LIBRARY_PATH}
    export PYTHONPATH=${PYTHONPATH}:${CEPH_SRC}/pybind
    for x in ${CEPH_ROOT}/lib/cython_modules/lib* ; do
        export PYTHONPATH="${PYTHONPATH}:${x}"
    done
fi

# These vars facilitate running this script in an environment with
# ceph installed from packages, like teuthology. These are not defined
# by default.
#
# RBD_MIRROR_USE_EXISTING_CLUSTER - if set, do not start and stop ceph clusters
# RBD_MIRROR_USE_RBD_MIRROR - if set, use an existing instance of rbd-mirror
#                             running as ceph client $CEPH_ID. If empty,
#                             this script will start and stop rbd-mirror

#
# Functions
#

# Parse a value in format cluster[:instance] and set cluster and instance vars.
set_cluster_instance()
{
    local val=$1
    local cluster_var_name=$2
    local instance_var_name=$3

    cluster=${val%:*}
    instance=${val##*:}

    if [ "${instance}" =  "${val}" ]; then
	# instance was not specified, use default
	instance=0
    fi

    eval ${cluster_var_name}=${cluster}
    eval ${instance_var_name}=${instance}
}

daemon_asok_file()
{
    local local_cluster=$1
    local cluster=$2
    local instance

    set_cluster_instance "${local_cluster}" local_cluster instance

    if [ -n "${RBD_MIRROR_USE_RBD_MIRROR}" ]; then
        echo $(ceph-conf --cluster $local_cluster --name "client.${CEPH_ID}" 'admin socket')
    else
        echo "${TEMPDIR}/rbd-mirror.${local_cluster}_daemon.${instance}.${cluster}.asok"
    fi
}

daemon_pid_file()
{
    local cluster=$1
    local instance

    set_cluster_instance "${cluster}" cluster instance

    if [ -n "${RBD_MIRROR_USE_RBD_MIRROR}" ]; then
        echo $(ceph-conf --cluster $cluster --name "client.${CEPH_ID}" 'pid file')
    else
        echo "${TEMPDIR}/rbd-mirror.${cluster}_daemon.${instance}.pid"
    fi
}

testlog()
{
    echo $(date '+%F %T') $@ | tee -a "${TEMPDIR}/rbd-mirror.test.log" >&2
}

expect_failure()
{
    local expected="$1" ; shift
    local out=${TEMPDIR}/expect_failure.out

    if "$@" > ${out} 2>&1 ; then
        cat ${out} >&2
        return 1
    fi

    if [ -z "${expected}" ]; then
	return 0
    fi

    if ! grep -q "${expected}" ${out} ; then
        cat ${out} >&2
        return 1
    fi

    return 0
}

setup()
{
    local c
    trap cleanup INT TERM EXIT

    if [ -n "${RBD_MIRROR_TEMDIR}" ]; then
	test -d "${RBD_MIRROR_TEMDIR}" ||
	mkdir "${RBD_MIRROR_TEMDIR}"
	TEMPDIR="${RBD_MIRROR_TEMDIR}"
	cd ${TEMPDIR}
    else
	TEMPDIR=`mktemp -d`
    fi

    if [ -z "${RBD_MIRROR_USE_EXISTING_CLUSTER}" ]; then
        cd ${CEPH_ROOT}
        CEPH_ARGS='' ${CEPH_SRC}/mstart.sh ${CLUSTER1} -n ${RBD_MIRROR_VARGS}
        CEPH_ARGS='' ${CEPH_SRC}/mstart.sh ${CLUSTER2} -n ${RBD_MIRROR_VARGS}

        CEPH_ARGS='' ceph --conf run/${CLUSTER1}/ceph.conf \
            auth get-or-create client.${USER_ID} mon 'profile rbd' osd 'profile rbd' >> \
            run/${CLUSTER1}/keyring
        CEPH_ARGS='' ceph --conf run/${CLUSTER2}/ceph.conf \
            auth get-or-create client.${USER_ID} mon 'profile rbd' osd 'profile rbd' >> \
            run/${CLUSTER2}/keyring

	rm -f ${TEMPDIR}/${CLUSTER1}.conf
        ln -s $(readlink -f run/${CLUSTER1}/ceph.conf) \
           ${TEMPDIR}/${CLUSTER1}.conf
	rm -f ${TEMPDIR}/${CLUSTER2}.conf
        ln -s $(readlink -f run/${CLUSTER2}/ceph.conf) \
           ${TEMPDIR}/${CLUSTER2}.conf

        cd ${TEMPDIR}
    fi

    CEPH_ARGS='' ceph --cluster ${CLUSTER1} osd pool create ${POOL} 64 64
    CEPH_ARGS='' ceph --cluster ${CLUSTER1} osd pool create ${PARENT_POOL} 64 64
    CEPH_ARGS='' ceph --cluster ${CLUSTER2} osd pool create ${PARENT_POOL} 64 64
    CEPH_ARGS='' ceph --cluster ${CLUSTER2} osd pool create ${POOL} 64 64

    CEPH_ARGS='' rbd --cluster ${CLUSTER1} pool init ${POOL}
    CEPH_ARGS='' rbd --cluster ${CLUSTER2} pool init ${POOL}
    CEPH_ARGS='' rbd --cluster ${CLUSTER1} pool init ${PARENT_POOL}
    CEPH_ARGS='' rbd --cluster ${CLUSTER2} pool init ${PARENT_POOL}

    rbd --cluster ${CLUSTER1} mirror pool enable ${POOL} pool
    rbd --cluster ${CLUSTER2} mirror pool enable ${POOL} pool
    rbd --cluster ${CLUSTER1} mirror pool enable ${PARENT_POOL} image
    rbd --cluster ${CLUSTER2} mirror pool enable ${PARENT_POOL} image

    rbd --cluster ${CLUSTER1} mirror pool peer add ${POOL} ${CLUSTER2}
    rbd --cluster ${CLUSTER2} mirror pool peer add ${POOL} ${CLUSTER1}
    rbd --cluster ${CLUSTER1} mirror pool peer add ${PARENT_POOL} ${CLUSTER2}
    rbd --cluster ${CLUSTER2} mirror pool peer add ${PARENT_POOL} ${CLUSTER1}
}

cleanup()
{
    test  -n "${RBD_MIRROR_NOCLEANUP}" && return
    local cluster instance

    set +e

    for cluster in "${CLUSTER1}" "${CLUSTER2}"; do
	for instance in `seq 0 9`; do
	    stop_mirror "${cluster}:${instance}"
	done
    done

    if [ -z "${RBD_MIRROR_USE_EXISTING_CLUSTER}" ]; then
        cd ${CEPH_ROOT}
        CEPH_ARGS='' ${CEPH_SRC}/mstop.sh ${CLUSTER1}
        CEPH_ARGS='' ${CEPH_SRC}/mstop.sh ${CLUSTER2}
    else
        CEPH_ARGS='' ceph --cluster ${CLUSTER1} osd pool rm ${POOL} ${POOL} --yes-i-really-really-mean-it
        CEPH_ARGS='' ceph --cluster ${CLUSTER2} osd pool rm ${POOL} ${POOL} --yes-i-really-really-mean-it
        CEPH_ARGS='' ceph --cluster ${CLUSTER1} osd pool rm ${PARENT_POOL} ${PARENT_POOL} --yes-i-really-really-mean-it
        CEPH_ARGS='' ceph --cluster ${CLUSTER2} osd pool rm ${PARENT_POOL} ${PARENT_POOL} --yes-i-really-really-mean-it
    fi
    test "${RBD_MIRROR_TEMDIR}" = "${TEMPDIR}" ||
    rm -Rf ${TEMPDIR}
}

start_mirror()
{
    local cluster=$1
    local instance

    set_cluster_instance "${cluster}" cluster instance

    test -n "${RBD_MIRROR_USE_RBD_MIRROR}" && return

    rbd-mirror \
	--cluster ${cluster} \
        --id mirror \
	--pid-file=$(daemon_pid_file "${cluster}:${instance}") \
	--log-file=${TEMPDIR}/rbd-mirror.${cluster}_daemon.${instance}.log \
	--admin-socket=${TEMPDIR}/rbd-mirror.${cluster}_daemon.${instance}.\$cluster.asok \
	--rbd-mirror-delete-retry-interval=5 \
	--rbd-mirror-image-state-check-interval=5 \
	--rbd-mirror-journal-poll-age=1 \
	--rbd-mirror-pool-replayers-refresh-interval=5 \
	--debug-rbd=30 --debug-journaler=30 \
	--debug-rbd_mirror=30 \
	--daemonize=true \
	${RBD_MIRROR_ARGS}
}

stop_mirror()
{
    local cluster=$1
    local sig=$2

    test -n "${RBD_MIRROR_USE_RBD_MIRROR}" && return

    local pid
    pid=$(cat $(daemon_pid_file "${cluster}") 2>/dev/null) || :
    if [ -n "${pid}" ]
    then
	kill ${sig} ${pid}
	for s in 1 2 4 8 16 32; do
	    sleep $s
	    ps auxww | awk -v pid=${pid} '$2 == pid {print; exit 1}' && break
	done
	ps auxww | awk -v pid=${pid} '$2 == pid {print; exit 1}'
    fi
    rm -f $(daemon_asok_file "${cluster}" "${CLUSTER1}")
    rm -f $(daemon_asok_file "${cluster}" "${CLUSTER2}")
    rm -f $(daemon_pid_file "${cluster}")
}

admin_daemon()
{
    local cluster=$1 ; shift
    local instance

    set_cluster_instance "${cluster}" cluster instance

    local asok_file=$(daemon_asok_file "${cluster}:${instance}" "${cluster}")
    test -S "${asok_file}"

    ceph --admin-daemon ${asok_file} $@
}

status()
{
    local cluster daemon image_pool image

    for cluster in ${CLUSTER1} ${CLUSTER2}
    do
	echo "${cluster} status"
	ceph --cluster ${cluster} -s
	echo

	for image_pool in ${POOL} ${PARENT_POOL}
	do
	    echo "${cluster} ${image_pool} images"
	    rbd --cluster ${cluster} -p ${image_pool} ls
	    echo

	    echo "${cluster} ${image_pool} mirror pool status"
	    rbd --cluster ${cluster} -p ${image_pool} mirror pool status --verbose
	    echo

	    for image in `rbd --cluster ${cluster} -p ${image_pool} ls 2>/dev/null`
	    do
	        echo "image ${image} info"
	        rbd --cluster ${cluster} -p ${image_pool} info ${image}
	        echo
	        echo "image ${image} journal status"
	        rbd --cluster ${cluster} -p ${image_pool} journal status --image ${image}
	        echo
	    done
	done
    done

    local ret

    for cluster in "${CLUSTER1}" "${CLUSTER2}"
    do
	local pid_file=$(daemon_pid_file ${cluster} )
	if [ ! -e ${pid_file} ]
	then
	    echo "${cluster} rbd-mirror not running or unknown" \
		 "(${pid_file} not exist)"
	    continue
	fi

	local pid
	pid=$(cat ${pid_file} 2>/dev/null) || :
	if [ -z "${pid}" ]
	then
	    echo "${cluster} rbd-mirror not running or unknown" \
		 "(can't find pid using ${pid_file})"
	    ret=1
	    continue
	fi

	echo "${daemon} rbd-mirror process in ps output:"
	if ps auxww |
		awk -v pid=${pid} 'NR == 1 {print} $2 == pid {print; exit 1}'
	then
	    echo
	    echo "${cluster} rbd-mirror not running" \
		 "(can't find pid $pid in ps output)"
	    ret=1
	    continue
	fi
	echo

	local asok_file=$(daemon_asok_file ${cluster} ${cluster})
	if [ ! -S "${asok_file}" ]
	then
	    echo "${cluster} rbd-mirror asok is unknown (${asok_file} not exits)"
	    ret=1
	    continue
	fi

	echo "${cluster} rbd-mirror status"
	ceph --admin-daemon ${asok_file} rbd mirror status
	echo
    done

    return ${ret}
}

flush()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local cmd="rbd mirror flush"

    if [ -n "${image}" ]
    then
       cmd="${cmd} ${pool}/${image}"
    fi

    admin_daemon "${cluster}" ${cmd}
}

test_image_replay_state()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local test_state=$4
    local current_state=stopped

    admin_daemon "${cluster}" help |
	fgrep "\"rbd mirror status ${pool}/${image}\"" &&
    admin_daemon "${cluster}" rbd mirror status ${pool}/${image} |
	grep -i 'state.*Replaying' &&
    current_state=started

    test "${test_state}" = "${current_state}"
}

wait_for_image_replay_state()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local state=$4
    local s

    # TODO: add a way to force rbd-mirror to update replayers
    for s in 1 2 4 8 8 8 8 8 8 8 8 16 16; do
	sleep ${s}
	test_image_replay_state "${cluster}" "${pool}" "${image}" "${state}" && return 0
    done
    return 1
}

wait_for_image_replay_started()
{
    local cluster=$1
    local pool=$2
    local image=$3

    wait_for_image_replay_state "${cluster}" "${pool}" "${image}" started
}

wait_for_image_replay_stopped()
{
    local cluster=$1
    local pool=$2
    local image=$3

    wait_for_image_replay_state "${cluster}" "${pool}" "${image}" stopped
}

get_position()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local id_regexp=$4

    # Parse line like below, looking for the first position
    # [id=, commit_position=[positions=[[object_number=1, tag_tid=3, entry_tid=9], [object_number=0, tag_tid=3, entry_tid=8], [object_number=3, tag_tid=3, entry_tid=7], [object_number=2, tag_tid=3, entry_tid=6]]]]

    local status_log=${TEMPDIR}/${CLUSTER2}-${pool}-${image}.status
    rbd --cluster ${cluster} -p ${pool} journal status --image ${image} |
	tee ${status_log} >&2
    sed -nEe 's/^.*\[id='"${id_regexp}"',.*positions=\[\[([^]]*)\],.*state=connected.*$/\1/p' \
	${status_log}
}

get_master_position()
{
    local cluster=$1
    local pool=$2
    local image=$3

    get_position "${cluster}" "${pool}" "${image}" ''
}

get_mirror_position()
{
    local cluster=$1
    local pool=$2
    local image=$3

    get_position "${cluster}" "${pool}" "${image}" '..*'
}

wait_for_replay_complete()
{
    local local_cluster=$1
    local cluster=$2
    local pool=$3
    local image=$4
    local s master_pos mirror_pos last_mirror_pos
    local master_tag master_entry mirror_tag mirror_entry

    while true; do
        for s in 0.2 0.4 0.8 1.6 2 2 4 4 8 8 16 16 32 32; do
	    sleep ${s}
	    flush "${local_cluster}" "${pool}" "${image}"
	    master_pos=$(get_master_position "${cluster}" "${pool}" "${image}")
	    mirror_pos=$(get_mirror_position "${cluster}" "${pool}" "${image}")
	    test -n "${master_pos}" -a "${master_pos}" = "${mirror_pos}" && return 0
            test "${mirror_pos}" != "${last_mirror_pos}" && break
        done

        test "${mirror_pos}" = "${last_mirror_pos}" && return 1
        last_mirror_pos="${mirror_pos}"

        # handle the case where the mirror is ahead of the master
        master_tag=$(echo "${master_pos}" | grep -Eo "tag_tid=[0-9]*" | cut -d'=' -f 2)
        mirror_tag=$(echo "${mirror_pos}" | grep -Eo "tag_tid=[0-9]*" | cut -d'=' -f 2)
        master_entry=$(echo "${master_pos}" | grep -Eo "entry_tid=[0-9]*" | cut -d'=' -f 2)
        mirror_entry=$(echo "${mirror_pos}" | grep -Eo "entry_tid=[0-9]*" | cut -d'=' -f 2)
        test "${master_tag}" = "${mirror_tag}" -a ${master_entry} -le ${mirror_entry} && return 0
    done
    return 1
}

test_status_in_pool_dir()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local state_pattern=$4
    local description_pattern=$5

    local status_log=${TEMPDIR}/${cluster}-${image}.mirror_status
    rbd --cluster ${cluster} -p ${pool} mirror image status ${image} |
	tee ${status_log} >&2
    grep "state: .*${state_pattern}" ${status_log} || return 1
    grep "description: .*${description_pattern}" ${status_log} || return 1
}

wait_for_status_in_pool_dir()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local state_pattern=$4
    local description_pattern=$5

    for s in 1 2 4 8 8 8 8 8 8 8 8 16 16; do
	sleep ${s}
	test_status_in_pool_dir ${cluster} ${pool} ${image} ${state_pattern} ${description_pattern} && return 0
    done
    return 1
}

create_image()
{
    local cluster=$1 ; shift
    local pool=$1 ; shift
    local image=$1 ; shift
    local size=128

    if [ -n "$1" ]; then
	size=$1
	shift
    fi

    rbd --cluster ${cluster} -p ${pool} create --size ${size} \
	--image-feature layering,exclusive-lock,journaling $@ ${image}
}

set_image_meta()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local key=$4
    local val=$5

    rbd --cluster ${cluster} -p ${pool} image-meta set ${image} $key $val
}

compare_image_meta()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local key=$4
    local value=$5

    test `rbd --cluster ${cluster} -p ${pool} image-meta get ${image} ${key}` = "${value}"
}

rename_image()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local new_name=$4

    rbd --cluster=${cluster} -p ${pool} rename ${image} ${new_name}
}

remove_image()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster=${cluster} -p ${pool} snap purge ${image}
    rbd --cluster=${cluster} -p ${pool} rm ${image}
}

remove_image_retry()
{
    local cluster=$1
    local pool=$2
    local image=$3

    for s in 1 2 4 8 16 32; do
        remove_image ${cluster} ${pool} ${image} && return 0
        sleep ${s}
    done
    return 1
}

clone_image()
{
    local cluster=$1
    local parent_pool=$2
    local parent_image=$3
    local parent_snap=$4
    local clone_pool=$5
    local clone_image=$6

    rbd --cluster ${cluster} clone ${parent_pool}/${parent_image}@${parent_snap} \
	${clone_pool}/${clone_image} --image-feature layering,exclusive-lock,journaling
}

disconnect_image()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster ${cluster} -p ${pool} journal client disconnect \
	--image ${image}
}

create_snapshot()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap=$4

    rbd --cluster ${cluster} -p ${pool} snap create ${image}@${snap}
}

remove_snapshot()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap=$4

    rbd --cluster ${cluster} -p ${pool} snap rm ${image}@${snap}
}

rename_snapshot()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap=$4
    local new_snap=$5

    rbd --cluster ${cluster} -p ${pool} snap rename ${image}@${snap} ${image}@${new_snap}
}

purge_snapshots()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster ${cluster} -p ${pool} snap purge ${image}
}

protect_snapshot()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap=$4

    rbd --cluster ${cluster} -p ${pool} snap protect ${image}@${snap}
}

unprotect_snapshot()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap=$4

    rbd --cluster ${cluster} -p ${pool} snap unprotect ${image}@${snap}
}

wait_for_snap_present()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local snap_name=$4
    local s

    for s in 1 2 4 8 8 8 8 8 8 8 8 16 16 16 16 32 32 32 32; do
	sleep ${s}
        rbd --cluster ${cluster} -p ${pool} info ${image}@${snap_name} || continue
        return 0
    done
    return 1
}

write_image()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local count=$4
    local size=$5

    test -n "${size}" || size=4096

    rbd --cluster ${cluster} -p ${pool} bench ${image} --io-type write \
	--io-size ${size} --io-threads 1 --io-total $((size * count)) \
	--io-pattern rand
}

stress_write_image()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local duration=$(awk 'BEGIN {srand(); print int(10 * rand()) + 5}')

    timeout ${duration}s ceph_test_rbd_mirror_random_write \
	--cluster ${cluster} ${pool} ${image} \
	--debug-rbd=20 --debug-journaler=20 \
	2> ${TEMPDIR}/rbd-mirror-random-write.log || true
}

compare_images()
{
    local pool=$1
    local image=$2

    local rmt_export=${TEMPDIR}/${CLUSTER2}-${pool}-${image}.export
    local loc_export=${TEMPDIR}/${CLUSTER1}-${pool}-${image}.export

    rm -f ${rmt_export} ${loc_export}
    rbd --cluster ${CLUSTER2} -p ${pool} export ${image} ${rmt_export}
    rbd --cluster ${CLUSTER1} -p ${pool} export ${image} ${loc_export}
    cmp ${rmt_export} ${loc_export}
    rm -f ${rmt_export} ${loc_export}
}

demote_image()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster=${cluster} mirror image demote ${pool}/${image}
}

promote_image()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local force=$4

    rbd --cluster=${cluster} mirror image promote ${pool}/${image} ${force}
}

set_pool_mirror_mode()
{
    local cluster=$1
    local pool=$2
    local mode=$3

    rbd --cluster=${cluster} -p ${pool} mirror pool enable ${mode}
}

disable_mirror()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster=${cluster} mirror image disable ${pool}/${image}
}

enable_mirror()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster=${cluster} mirror image enable ${pool}/${image}
}

test_image_present()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local test_state=$4
    local image_id=$5
    local current_state=deleted
    local current_image_id

    current_image_id=$(get_image_id ${cluster} ${pool} ${image})
    test -n "${current_image_id}" &&
    test -z "${image_id}" -o "${image_id}" = "${current_image_id}" &&
    current_state=present

    test "${test_state}" = "${current_state}"
}

wait_for_image_present()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local state=$4
    local image_id=$5
    local s

    test -n "${image_id}" ||
    image_id=$(get_image_id ${cluster} ${pool} ${image})

    # TODO: add a way to force rbd-mirror to update replayers
    for s in 0.1 1 2 4 8 8 8 8 8 8 8 8 16 16 32 32; do
	sleep ${s}
	test_image_present \
            "${cluster}" "${pool}" "${image}" "${state}" "${image_id}" &&
        return 0
    done
    return 1
}

get_image_id()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster=${cluster} -p ${pool} info ${image} |
	sed -ne 's/^.*block_name_prefix: rbd_data\.//p'
}

request_resync_image()
{
    local cluster=$1
    local pool=$2
    local image=$3
    local image_id_var_name=$4

    eval "${image_id_var_name}='$(get_image_id ${cluster} ${pool} ${image})'"
    eval 'test -n "$'${image_id_var_name}'"'

    rbd --cluster=${cluster} -p ${pool} mirror image resync ${image}
}

get_image_data_pool()
{
    local cluster=$1
    local pool=$2
    local image=$3

    rbd --cluster ${cluster} -p ${pool} info ${image} |
        awk '$1 == "data_pool:" {print $2}'
}

#
# Main
#

if [ "$#" -gt 0 ]
then
    if [ -z "${RBD_MIRROR_TEMDIR}" ]
    then
       echo "RBD_MIRROR_TEMDIR is not set" >&2
       exit 1
    fi

    TEMPDIR="${RBD_MIRROR_TEMDIR}"
    cd ${TEMPDIR}
    $@
    exit $?
fi

set -xe

setup
