openwrt-owl/package/base-files/files/lib/functions/service.sh

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#
# service: simple wrapper around start-stop-daemon
#
# Usage: service ACTION EXEC ARGS...
#
# Action:
# -C check if EXEC is alive
# -S start EXEC, passing it ARGS as its arguments
# -K kill EXEC, sending it a TERM signal if not specified otherwise
#
# Environment variables exposed:
# SERVICE_DAEMONIZE run EXEC in background
# SERVICE_WRITE_PID create a pid-file and use it for matching
# SERVICE_MATCH_EXEC use EXEC command-line for matching (default)
# SERVICE_MATCH_NAME use EXEC process name for matching
# SERVICE_USE_PID assume EXEC create its own pid-file and use it for matching
# SERVICE_NAME process name to use (default to EXEC file part)
# SERVICE_PID_FILE pid file to use (default to /var/run/$SERVICE_NAME.pid)
# SERVICE_SIG signal to send when using -K
# SERVICE_SIG_RELOAD default signal used when reloading
# SERVICE_SIG_STOP default signal used when stopping
# SERVICE_STOP_TIME time to wait for a process to stop gracefully before killing it
# SERVICE_UID user EXEC should be run as
# SERVICE_GID group EXEC should be run as
#
# SERVICE_DEBUG don't do anything, but show what would be done
# SERVICE_QUIET don't print anything
#
SERVICE_QUIET=1
SERVICE_SIG_RELOAD="HUP"
SERVICE_SIG_STOP="TERM"
SERVICE_STOP_TIME=5
SERVICE_MATCH_EXEC=1
service() {
local ssd
local exec
local name
local start
ssd="${SERVICE_DEBUG:+echo }start-stop-daemon${SERVICE_QUIET:+ -q}"
case "$1" in
-C)
ssd="$ssd -K -t"
;;
-S)
ssd="$ssd -S${SERVICE_DAEMONIZE:+ -b}${SERVICE_WRITE_PID:+ -m}"
start=1
;;
-K)
ssd="$ssd -K${SERVICE_SIG:+ -s $SERVICE_SIG}"
;;
*)
echo "service: unknown ACTION '$1'" 1>&2
return 1
esac
shift
exec="$1"
[ -n "$exec" ] || {
echo "service: missing argument" 1>&2
return 1
}
[ -x "$exec" ] || {
echo "service: file '$exec' is not executable" 1>&2
return 1
}
name="${SERVICE_NAME:-${exec##*/}}"
[ -z "$SERVICE_USE_PID$SERVICE_WRITE_PID$SERVICE_PID_FILE" ] \
|| ssd="$ssd -p ${SERVICE_PID_FILE:-/var/run/$name.pid}"
[ -z "$SERVICE_MATCH_NAME" ] || ssd="$ssd -n $name"
ssd="$ssd${SERVICE_UID:+ -c $SERVICE_UID${SERVICE_GID:+:$SERVICE_GID}}"
[ -z "$SERVICE_MATCH_EXEC$start" ] || ssd="$ssd -x $exec"
shift
$ssd${1:+ -- "$@"}
}
service_check() {
service -C "$@"
}
service_signal() {
SERVICE_SIG="${SERVICE_SIG:-USR1}" service -K "$@"
}
service_start() {
service -S "$@"
}
service_stop() {
local try
SERVICE_SIG="${SERVICE_SIG:-$SERVICE_SIG_STOP}" service -K "$@" || return 1
while [ $((try++)) -lt $SERVICE_STOP_TIME ]; do
service -C "$@" || return 0
sleep 1
done
SERVICE_SIG="KILL" service -K "$@"
sleep 1
! service -C "$@"
}
service_reload() {
SERVICE_SIG="${SERVICE_SIG:-$SERVICE_SIG_RELOAD}" service -K "$@"
}