#!/bin/sh
#
# invoke-rc.d.sysvinit - Executes initscript actions
#
# SysVinit /etc/rc?.d version for Debian's sysvinit package
#
# Copyright (C) 2000,2001 Henrique de Moraes Holschuh <[email protected]>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the Free
# Software Foundation; either version 2 of the License, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
# for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.

# Constants
RUNLEVELHELPER=/sbin/runlevel
POLICYHELPER=/usr/sbin/policy-rc.d
INITDPREFIX=/etc/init.d/
UPSTARTDIR=/etc/init/
RCDPREFIX=/etc/rc

# Options
BEQUIET=
MODE=
ACTION=
FALLBACK=
NOFALLBACK=
FORCE=
RETRY=
RETURNFAILURE=
RC=
is_upstart=

# Shell options
set +e

dohelp () {
#
# outputs help and usage
#
cat <<EOF

invoke-rc.d, Debian/SysVinit (/etc/rc?.d) initscript subsystem.
Copyright (c) 2000,2001 Henrique de Moraes Holschuh <[email protected]>

Usage:
invoke-rc.d [options] <basename> <action> [extra parameters]

basename - Initscript ID, as per update-rc.d(8)
action - Initscript action. Known actions are:
start, [force-]stop, restart,
[force-]reload, status
WARNING: not all initscripts implement all of the above actions.

extra parameters are passed as is to the initscript, following
the action (first initscript parameter).

Options:
--quiet
Quiet mode, no error messages are generated.
--force
Try to run the initscript regardless of policy and subsystem
non-fatal errors.
--try-anyway
Try to run init script even if a non-fatal error is found.
--disclose-deny
Return status code 101 instead of status code 0 if
initscript action is denied by local policy rules or
runlevel constrains.
--query
Returns one of status codes 100-106, does not run
the initscript. Implies --disclose-deny and --no-fallback.
--no-fallback
Ignores any fallback action requests by the policy layer.
Warning: this is usually a very *bad* idea for any actions
other than "start".
--help
Outputs help message to stdout

EOF
}

printerror () {
#
# prints an error message
# $* - error message
#
if test x${BEQUIET} = x ; then
echo `basename $0`: "$*" >&2
fi
}

formataction () {
#
# formats a list in $* into $printaction
# for human-friendly printing to stderr
# and sets $naction to action or actions
#
printaction=`echo $* | sed 's/ /, /g'`
if test $# -eq 1 ; then
naction=action
else
naction=actions
fi
}

querypolicy () {
#
# queries policy database
# returns: $RC = 104 - ok, run
# $RC = 101 - ok, do not run
# other - exit with status $RC, maybe run if $RETRY
# initial status of $RC is taken into account.
#

policyaction="${ACTION}"
if test x${RC} = "x101" ; then
if test "${ACTION}" = "start" || test "${ACTION}" = "restart" ; then
policyaction="(${ACTION})"
fi
fi

if test "x${POLICYHELPER}" != x && test -x "${POLICYHELPER}" ; then
FALLBACK=`${POLICYHELPER} ${BEQUIET} ${INITSCRIPTID} "${policyaction}" ${RL}`
RC=$?
formataction ${ACTION}
case ${RC} in
0) RC=104
;;
1) RC=105
;;
101) if test x${FORCE} != x ; then
printerror Overriding policy-rc.d denied execution of ${printaction}.
RC=104
else
printerror policy-rc.d denied execution of ${printaction}.
fi
;;
esac
if test x${MODE} != xquery ; then
case ${RC} in
105) printerror policy-rc.d query returned \"behaviour undefined\",
printerror assuming \"${printaction}\" is allowed.
RC=104
;;
106) formataction ${FALLBACK}
if test x${FORCE} = x ; then
if test x${NOFALLBACK} = x ; then
ACTION="${FALLBACK}"
printerror executing ${naction} \"${printaction}\" instead due to policy-rc.d request.
RC=104
else
printerror ignoring policy-rc.d fallback request: ${printaction}.
RC=101
fi
else
printerror ignoring policy-rc.d fallback request: ${printaction}.
RC=104
fi
;;
esac
fi
case ${RC} in
100|101|102|103|104|105|106) ;;
*) printerror WARNING: policy-rc.d returned unexpected error status ${RC}, 102 used instead.
RC=102
;;
esac
else
if test x${RC} = x ; then
RC=104
fi
fi
return
}

verifyparameter () {
#
# Verifies if $1 is not null, and $# = 1
#
if test $# -eq 0 ; then
printerror syntax error: invalid empty parameter
exit 103
elif test $# -ne 1 ; then
printerror syntax error: embedded blanks are not allowed in \"$*\"
exit 103
fi
return
}

##
## main
##

## Verifies command line arguments

if test $# -eq 0 ; then
printerror syntax error: missing required parameter, --help assumed
dohelp
exit 103
fi

state=I
while test $# -gt 0 && test ${state} != III ; do
case "$1" in
--help) dohelp
exit 0
;;
--quiet) BEQUIET=--quiet
;;
--force) FORCE=yes
RETRY=yes
;;
--try-anyway)
RETRY=yes
;;
--disclose-deny)
RETURNFAILURE=yes
;;
--query) MODE=query
RETURNFAILURE=yes
;;
--no-fallback)
NOFALLBACK=yes
;;
--*) printerror syntax error: unknown option \"$1\"
exit 103
;;
*) case ${state} in
I) verifyparameter $1
INITSCRIPTID=$1
;;
II) verifyparameter $1
ACTION=$1
;;
esac
state=${state}I
;;
esac
shift
done

if test ${state} != III ; then
printerror syntax error: missing required parameter
exit 103
fi

#NOTE: It may not be obvious, but "$@" from this point on must expand
#to the extra initscript parameters, except inside functions.

## sanity checks and just-in-case warnings.
case ${ACTION} in
start|stop|force-stop|restart|reload|force-reload|status)
;;
*)
if test "x${POLICYHELPER}" != x && test -x "${POLICYHELPER}" ; then
printerror action ${ACTION} is unknown, but proceeding anyway.
fi
;;
esac

# If we're running on upstart and there's an upstart job of this name, do
# the rest with upstart instead of calling the init script.
if which initctl >/dev/null && initctl version | grep -q upstart \
&& [ -e "$UPSTARTDIR/${INITSCRIPTID}.conf" ]
then
is_upstart=1
elif test ! -f "${INITDPREFIX}${INITSCRIPTID}" ; then
## Verifies if the given initscript ID is known
## For sysvinit, this error is critical
printerror unknown initscript, ${INITDPREFIX}${INITSCRIPTID} not found.
if [ ! -e "$UPSTARTDIR/${INITSCRIPTID}.conf" ]; then
# If the init script doesn't exist, but the upstart job does, we
# defer the error exit; we might be running in a chroot and
# policy-rc.d might say not to start the job anyway, in which case
# we don't want to exit non-zero.
exit 100
fi
fi

## Queries sysvinit for the current runlevel
RL=`${RUNLEVELHELPER} | sed 's/.*\ //'`
if test ! $? ; then
printerror "could not determine current runlevel"
if test x${RETRY} = x ; then
exit 102
fi
RL=
fi

## Running ${RUNLEVELHELPER} to get current runlevel does not work in
## the boot runlevel (scripts in /etc/rcS.d/), as /var/run/utmp
## contains runlevel 0 or 6 (written at shutdown) at that point.
if test x${RL} = x0 || test x${RL} = x6 ; then
if ps -fp 1 | grep -q 'init boot' ; then
RL=S
fi
fi

## Handles shutdown sequences VERY safely
## i.e.: forget about policy, and do all we can to run the script.
## BTW, why the heck are we being run in a shutdown runlevel?!
if test x${RL} = x0 || test x${RL} = x6 ; then
FORCE=yes
RETRY=yes
POLICYHELPER=
BEQUIET=
printerror "-----------------------------------------------------"
printerror "WARNING: 'invoke-rc.d ${INITSCRIPTID} ${ACTION}' called"
printerror "during shutdown sequence."
printerror "enabling safe mode: initscript policy layer disabled"
printerror "-----------------------------------------------------"
fi

## Verifies the existance of proper S??initscriptID and K??initscriptID
## *links* in the proper /etc/rc?.d/ directory
verifyrclink () {
#
# verifies if parameters are non-dangling symlinks
# all parameters are verified
#
doexit=
while test $# -gt 0 ; do
if test ! -L "$1" ; then
printerror not a symlink: $1
doexit=102
fi
if test ! -f "$1" ; then
printerror dangling symlink: $1
doexit=102
fi
shift
done
if test x${doexit} != x && test x${RETRY} = x; then
exit ${doexit}
fi
return 0
}

# we do handle multiple links per runlevel
# but we don't handle embedded blanks in link names :-(
if test x${RL} != x ; then
SLINK=`ls -d -Q ${RCDPREFIX}${RL}.d/S[0-9][0-9]${INITSCRIPTID} 2>/dev/null | xargs`
KLINK=`ls -d -Q ${RCDPREFIX}${RL}.d/K[0-9][0-9]${INITSCRIPTID} 2>/dev/null | xargs`
SSLINK=`ls -d -Q ${RCDPREFIX}S.d/S[0-9][0-9]${INITSCRIPTID} 2>/dev/null | xargs`

verifyrclink ${SLINK} ${KLINK} ${SSLINK}
fi

testexec () {
#
# returns true if any of the parameters is
# executable (after following links)
#
while test $# -gt 0 ; do
if test -x "$1" ; then
return 0
fi
shift
done
return 1
}

RC=

###
### LOCAL INITSCRIPT POLICY: Enforce need of a start entry
### in either runlevel S or current runlevel to allow start
### or restart.
###
case ${ACTION} in
start|restart)
if testexec ${SLINK} ; then
RC=104
elif testexec ${KLINK} ; then
RC=101
elif testexec ${SSLINK} ; then
RC=104
fi
;;
esac

# test if /etc/init.d/initscript is actually executable
if [ -n "$is_upstart" ] || testexec "${INITDPREFIX}${INITSCRIPTID}" ; then
if test x${RC} = x && test x${MODE} = xquery ; then
RC=105
fi

# call policy layer
querypolicy
case ${RC} in
101|104)
;;
*) if test x${MODE} != xquery ; then
printerror policy-rc.d returned error status ${RC}
if test x${RETRY} = x ; then
exit ${RC}
else
RC=102
fi
fi
;;
esac
elif [ -z "$is_upstart" ] && test ! -f "${INITDPREFIX}${INITSCRIPTID}" ; then
# call policy layer. If the policy denies the execution, pass it on.
# otherwise, if the policy *allows* the execution, there's a
# misconfiguration somewhere and we throw an error.
querypolicy
case $RC in
101)
;;
*)
exit 100
;;
esac
else
###
### LOCAL INITSCRIPT POLICY: non-executable initscript; deny exec.
### (this is common sense, actually :^P )
###
RC=101
fi

## Handles --query
if test x${MODE} = xquery ; then
exit ${RC}
fi


setechoactions () {
if test $# -gt 1 ; then
echoaction=true
else
echoaction=
fi
}
getnextaction () {
saction=$1
shift
ACTION="$@"
}

clean_ldpreload () {
# clean_ldpreload(name): remove occurences of name from LD_PRELOAD
local name="$1" oifs="$IFS" found=0 tok="" nval="" delim=" "

# LD_PRELOAD can be space or colon separated items
# assume ':' in value indicates ':' otherwise space
[ "${LD_PRELOAD#*:}" = "$LD_PRELOAD" ] || delim=":"

IFS="$delim"
for tok in $LD_PRELOAD; do
[ "${tok##*/}" = "$name" ] && found=1 || nval="${nval}${delim}$tok"
done
IFS="$oifs"
# if we didn't find anything, dont change anything.
[ "$found" = "1" ] || return 0
LD_PRELOAD="${nval#$delim}"
}

if [ -n "$is_upstart" ]; then
RUNNING=
DISABLED=
if status "$INITSCRIPTID" 2>/dev/null | grep -q ' start/'; then
RUNNING=1
fi
UPSTART_VERSION_RUNNING=$(initctl version|awk '{print $3}'|tr -d ')')

if dpkg --compare-versions "$UPSTART_VERSION_RUNNING" ge 0.9.7
then
initctl show-config -e "$INITSCRIPTID"|grep -q '^ start on' || DISABLED=1
fi
fi

# remove eatmydata from LD_PRELOAD unless told not to (LP: #1257036)
[ "${INVOKE_RCD_ALLOW_EATMYDATA:-0}" != "0" ] ||
clean_ldpreload "libeatmydata.so"

## Executes initscript
## note that $ACTION is a space-separated list of actions
## to be attempted in order until one suceeds.
if test x${FORCE} != x || test ${RC} -eq 104 ; then
if [ -n "$is_upstart" ] || testexec "${INITDPREFIX}${INITSCRIPTID}" ; then
RC=102
setechoactions ${ACTION}
while test ! -z "${ACTION}" ; do
getnextaction ${ACTION}
if test ! -z ${echoaction} ; then
printerror executing initscript action \"${saction}\"...
fi

if [ -n "$is_upstart" ]; then
# Force Upstart to re-scan /etc/init for filesystems with
# broken inotify (such as overlayfs (LP: #882147)).
initctl reload-configuration >/dev/null 2>&1

case $saction in
status)
"$saction" "$INITSCRIPTID" && exit 0
;;
start|stop)
if [ -z "$RUNNING" ] && [ "$saction" = "stop" ]; then
exit 0
elif [ -n "$RUNNING" ] && [ "$saction" = "start" ]; then
exit 0
elif [ -n "$DISABLED" ] && [ "$saction" = "start" ]; then
exit 0
fi
$saction "$INITSCRIPTID" && exit 0
;;
restart)
if [ -n "$RUNNING" ] ; then
stop "$INITSCRIPTID"
fi

# If the job is disabled and is not currently
# running, the job is not restarted. However, if
# the job is disabled but has been forced into
# the running state, we *do* stop and restart it
# since this is expected behaviour
# for the admin who forced the start.
if [ -n "$DISABLED" ] && [ -z "$RUNNING" ]; then
exit 0
fi
start "$INITSCRIPTID" && exit 0
;;
reload|force-reload)
reload "$INITSCRIPTID" && exit 0
;;
*)
# This will almost certainly fail, but give it a try
initctl "$saction" "$INITSCRIPTID" && exit 0
;;
esac
else
"${INITDPREFIX}${INITSCRIPTID}" "${saction}" "$@" && exit 0
fi
RC=$?

if test ! -z "${ACTION}" ; then
printerror action \"${saction}\" failed, trying next action...
fi
done
printerror initscript ${INITSCRIPTID}, action \"${saction}\" failed.
exit ${RC}
fi
exit 102
fi

## Handles --disclose-deny and denied "status" action (bug #381497)
if test ${RC} -eq 101 && test x${RETURNFAILURE} = x ; then
if test "x${ACTION%% *}" = "xstatus"; then
printerror emulating initscript action \"status\", returning \"unknown\"
RC=4
else
RC=0
fi
else
formataction ${ACTION}
printerror initscript ${naction} \"${printaction}\" not executed.
fi

exit ${RC}