# This is a shell function library sourced by some Open vSwitch scripts.
# It is not intended to be invoked on its own.

# Copyright (C) 2009, 2010, 2011, 2012 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

## ----------------- ##
## configure options ##
## ----------------- ##

# All of these should be substituted by the Makefile at build time.
logdir=${OVS_LOGDIR-'/var/log/openvswitch'}                 # /var/log/openvswitch
rundir=${OVS_RUNDIR-'/run/openvswitch'}                 # /var/run/openvswitch
sysconfdir=${OVS_SYSCONFDIR-'/etc'}     # /etc
etcdir=$sysconfdir/openvswitch                  # /etc/openvswitch
datadir=${OVS_PKGDATADIR-'/usr/share/openvswitch'}        # /usr/share/openvswitch
bindir=${OVS_BINDIR-'/usr/bin'}                 # /usr/bin
sbindir=${OVS_SBINDIR-'/usr/bin'}              # /usr/sbin

# /etc/openvswitch or /var/lib/openvswitch
if test X"$OVS_DBDIR" != X; then
    dbdir=$OVS_DBDIR
elif test X"$OVS_SYSCONFDIR" != X; then
    dbdir=$OVS_SYSCONFDIR/openvswitch
else
    dbdir='/etc/openvswitch'
fi

ovs_ctl_log () {
    echo "$@" >> "${logdir}/ovs-ctl.log"
}

ovs_ctl () {
    case "$@" in
        *"=strace"*)
            # In case of running the daemon with strace, piping the o/p causes
            # the script to block (strace probably does not close the inherited
            # pipe). So, do not log the o/p to ovs-ctl.log.
            "${datadir}/scripts/ovs-ctl" "$@"
        ;;
        "status")
            # In case of the command 'status', we should return the exit status
            # of ovs-ctl. It is also useful to document the o/p in ovs-ctl.log.
            display=`"${datadir}/scripts/ovs-ctl" "$@" 2>&1`
            rc=$?
            if test -w "${logdir}/ovs-ctl.log"; then
                 echo "${display}" | tee -a "${logdir}/ovs-ctl.log"
            else
                 echo "${display}"
            fi
            return ${rc}
        ;;
        *)
            echo "`date -u`:$@" >> "${logdir}/ovs-ctl.log"
            "${datadir}/scripts/ovs-ctl" "$@" 2>&1 | tee -a "${logdir}/ovs-ctl.log"
        ;;
    esac
}

VERSION='2.7.1'

DAEMON_CWD=/

LC_ALL=C; export LC_ALL

## ------------- ##
## LSB functions ##
## ------------- ##

# Use the system's own implementations if it has any.
if test -e /etc/init.d/functions; then
    . /etc/init.d/functions
elif test -e /etc/rc.d/init.d/functions; then
    . /etc/rc.d/init.d/functions
elif test -e /lib/lsb/init-functions; then
    . /lib/lsb/init-functions
fi

# Implement missing functions (e.g. OpenSUSE lacks 'action').
if type log_success_msg >/dev/null 2>&1; then :; else
    log_success_msg () {
        printf '%s.\n' "$*"
    }
fi
if type log_failure_msg >/dev/null 2>&1; then :; else
    log_failure_msg () {
        printf '%s ... failed!\n' "$*"
    }
fi
if type log_warning_msg >/dev/null 2>&1; then :; else
    log_warning_msg () {
        printf '%s ... (warning).\n' "$*"
    }
fi
if type action >/dev/null 2>&1; then :; else
    action () {
       STRING=$1
       shift
       "$@"
       rc=$?
       if test $rc = 0; then
            log_success_msg "$STRING"
       else
            log_failure_msg "$STRING"
       fi
       return $rc
    }
fi

## ------- ##
## Daemons ##
## ------- ##

pid_exists () {
    # This is better than "kill -0" because it doesn't require permission to
    # send a signal (so daemon_status in particular works as non-root).
    test -d /proc/"$1"
}

pid_comm_check () {
    [ "$1" = "`cat /proc/$2/comm`" ]
}

# version_geq version_a version_b
#
# Compare (dot separated) version numbers.  Returns true (exit code 0) if
# version_a is greater or equal than version_b, otherwise false (exit code 1).
version_geq() {
    echo $1 $2 | awk '{
        n1 = split($1, a, ".");
        n2 = split($2, b, ".");
        n = (n1 > n2) ? n1 : n2;
        for (i = 1; i <= n; i++) {
            if (a[i]+0 < b[i]+0) exit 1
            if (a[i]+0 > b[i]+0) exit 0
        }
    }'
}

install_dir () {
    DIR="$1"
    INSTALL_USER="root"
    INSTALL_GROUP="root"
    [ "$OVS_USER" != "" ] && INSTALL_USER="${OVS_USER%:*}"
    [ "${OVS_USER##*:}" != "" ] && INSTALL_GROUP="${OVS_USER##*:}"

    if test ! -d "$DIR"; then
        install -d -m 755 -o "$INSTALL_USER" -g "$INSTALL_GROUP" "$DIR"
        restorecon "$DIR" >/dev/null 2>&1
    fi
}

start_daemon () {
    priority=$1
    wrapper=$2
    shift; shift
    daemon=$1
    strace=""

    # drop core files in a sensible place
    install_dir "$DAEMON_CWD"
    set "$@" --no-chdir
    cd "$DAEMON_CWD"

    # log file
    install_dir "$logdir"
    set "$@" --log-file="$logdir/$daemon.log"

    # pidfile and monitoring
    install_dir "$rundir"
    set "$@" --pidfile="$rundir/$daemon.pid"
    set "$@" --detach
    test X"$MONITOR" = Xno || set "$@" --monitor

    # wrapper
    case $wrapper in
        valgrind)
            if (valgrind --version) > /dev/null 2>&1; then
                set valgrind -q --leak-check=full --time-stamp=yes \
                    --log-file="$logdir/$daemon.valgrind.log.%p" "$@"
            else
                log_failure_msg "valgrind not installed, running $daemon without it"
            fi
            ;;
        strace)
            if (strace -V) > /dev/null 2>&1; then
                strace="strace -tt -T -s 256 -ff"
                if (strace -DV) > /dev/null 2>&1; then
                    # Has the -D option.
                    set $strace -D -o "$logdir/$daemon.strace.log" "$@"
                    strace=""
                fi
            else
                log_failure_msg "strace not installed, running $daemon without it"
            fi
            ;;
        glibc)
            set env MALLOC_CHECK_=2 MALLOC_PERTURB_=165 "$@"
            ;;
        '')
            ;;
        *)
            log_failure_msg "unknown wrapper $wrapper, running $daemon without it"
            ;;
    esac

    # priority
    if test X"$priority" != X; then
        set nice -n "$priority" "$@"
    fi

    action "Starting $daemon" "$@" || return 1

    if test X"$strace" != X; then
        # Strace doesn't have the -D option so we attach after the fact.
        setsid $strace -o "$logdir/$daemon.strace.log" \
            -p `cat $rundir/$daemon.pid` > /dev/null 2>&1 &
    fi
}

stop_daemon () {
    if test -e "$rundir/$1.pid"; then
        if pid=`cat "$rundir/$1.pid"`; then

            graceful="EXIT .1 .25 .65 1"
            actions="TERM .1 .25 .65 1 1 1 1 \
                     KILL 1 1 1 2 10 15 30 \
                     FAIL"
            version=`ovs-appctl -T 1 -t $rundir/$1.$pid.ctl version \
                     | awk 'NR==1{print $NF}'`

            # Use `ovs-appctl exit` only if the running daemon version
            # is >= 2.5.90.  This script might be used during upgrade to
            # stop older versions of daemons which do not behave correctly
            # with `ovs-appctl exit` (e.g. ovs-vswitchd <= 2.5.0 deletes
            # internal ports).
            if version_geq "$version" "2.5.90"; then
                actions="$graceful $actions"
            fi
            for action in $actions; do
                if pid_exists "$pid" >/dev/null 2>&1; then :; else
                    return 0
                fi
                case $action in
                    EXIT)
                        action "Exiting $1 ($pid)" \
                            ${bindir}/ovs-appctl -T 1 -t $rundir/$1.$pid.ctl exit
                        ;;
                    TERM)
                        action "Killing $1 ($pid)" kill $pid
                        ;;
                    KILL)
                        action "Killing $1 ($pid) with SIGKILL" kill -9 $pid
                        ;;
                    FAIL)
                        log_failure_msg "Killing $1 ($pid) failed"
                        return 1
                        ;;
                    *)
                        sleep $action
                        ;;
                esac
            done
        fi
    fi
    log_success_msg "$1 is not running"
}

daemon_status () {
    pidfile=$rundir/$1.pid
    if test -e "$pidfile"; then
        if pid=`cat "$pidfile"`; then
            if pid_exists "$pid"; then
                echo "$1 is running with pid $pid"
                return 0
            else
                echo "Pidfile for $1 ($pidfile) is stale"
            fi
        else
            echo "Pidfile for $1 ($pidfile) exists but cannot be read"
        fi
    else
        echo "$1 is not running"
    fi
    return 1
}

daemon_is_running () {
    pidfile=$rundir/$1.pid
    test -e "$pidfile" && pid=`cat "$pidfile"` && pid_exists "$pid" && pid_comm_check $1 $pid
} >/dev/null 2>&1

# Prints commands needed to move the ip address from interface $1 to interface
# $2
move_ip_address () {
    if [ -z "$1" ] || [ -z "$2" ]; then
        return
    fi
    dev="$1"
    dst="$2"

    # IP addresses (including IPv6).
    echo "ip addr flush dev $dev 2>/dev/null" # Suppresses "Nothing to flush".
    ip addr show dev $dev | while read addr; do
        set -- $addr

        # Check and trim family.
        family=$1
        shift
        case $family in
            inet | inet6) ;;
            *) continue ;;
        esac

        # Trim device off the end--"ip" insists on having "dev" precede it.
        addrcmd=
        while test $# != 0; do
            case $1 in
                dynamic)
                    # Omit kernel-maintained route.
                    continue 2
                    ;;
                scope)
                    if test "$2" = link -a "$family" != inet6; then
                        # Omit route derived from IP address, e.g.
                        # 172.16.0.0/16 derived from 172.16.12.34,
                        # but preserve IPv6 link-local address.
                        continue 2
                    fi
                    ;;
                "$dev"|"$dev:"*)
                    # Address label string
                    label=`echo $1 | sed "s/$dev/$dst/"`
                    addrcmd="$addrcmd label $label"
                    shift
                    continue
                    ;;
            esac
            addrcmd="$addrcmd $1"
            shift
        done
        if test "$1" != "$dev"; then
            addrcmd="$addrcmd $1"
        fi

        echo ip -f $family addr add $addrcmd dev $dst
    done
}

# Prints commands needed to move the ip route of interface $1 to interface $2
move_ip_routes () {
    if [ -z "$1" ] || [ -z "$2" ]; then
        return
    fi
    dev="$1"
    dst="$2"
    echo "ip route flush dev $dev proto boot 2>/dev/null" # Suppresses "Nothing to flush".
    ip route show dev $dev | while read route; do
        # "proto kernel" routes are installed by the kernel automatically.
        case $route in
            *" proto kernel "*) continue ;;
        esac

        echo "ip route add $route dev $dst"
    done
}

ovsdb_tool () {
    if [ "$OVS_USER" != "" ]; then
        runuser --user "${OVS_USER%:*}" -- ovsdb-tool -vconsole:off "$@"
    else
        ovsdb-tool -vconsole:off "$@"
    fi
}

create_db () {
    DB_FILE="$1"
    DB_SCHEMA="$2"
    action "Creating empty database $DB_FILE" ovsdb_tool create "$DB_FILE" "$DB_SCHEMA"
}

upgrade_db () {
    DB_FILE="$1"
    DB_SCHEMA="$2"

    schemaver=`ovsdb_tool schema-version "$DB_SCHEMA"`
    if test ! -e "$DB_FILE"; then
        log_warning_msg "$DB_FILE does not exist"
        install_dir `dirname $DB_FILE`
        create_db "$DB_FILE" "$DB_SCHEMA"
    elif test X"`ovsdb_tool needs-conversion "$DB_FILE" "$DB_SCHEMA"`" != Xno; then
        # Back up the old version.
        version=`ovsdb_tool db-version "$DB_FILE"`
        cksum=`ovsdb_tool db-cksum "$DB_FILE" | awk '{print $1}'`
        backup=$DB_FILE.backup$version-$cksum
        action "Backing up database to $backup" cp "$DB_FILE" "$backup" || return 1

        # Compact database.  This is important if the old schema did not enable
        # garbage collection (i.e. if it did not have any tables with "isRoot":
        # true) but the new schema does.  In that situation the old database
        # may contain a transaction that creates a record followed by a
        # transaction that creates the first use of the record.  Replaying that
        # series of transactions against the new database schema (as "convert"
        # does) would cause the record to be dropped by the first transaction,
        # then the second transaction would cause a referential integrity
        # failure (for a strong reference).
        #
        # Errors might occur on an Open vSwitch downgrade if ovsdb-tool doesn't
        # understand some feature of the schema used in the OVSDB version that
        # we're downgrading from, so we don't give up on error.
        action "Compacting database" ovsdb_tool compact "$DB_FILE"

        # Upgrade or downgrade schema.
        if action "Converting database schema" ovsdb_tool convert "$DB_FILE" "$DB_SCHEMA"; then
            :
        else
            log_warning_msg "Schema conversion failed, using empty database instead"
            rm -f "$DB_FILE"
            create_db "$DB_FILE" "$DB_SCHEMA"
        fi
    fi
}
