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

   1 #
   2 # service: simple wrapper around start-stop-daemon
   3 #
   4 # Usage: service ACTION EXEC ARGS...
   5 #
   6 # Action:
   7 #   -C  check if EXEC is alive
   8 #   -S  start EXEC, passing it ARGS as its arguments
   9 #   -K  kill EXEC, sending it a TERM signal if not specified otherwise
  10 #
  11 # Environment variables exposed:
  12 #   SERVICE_DAEMONIZE   run EXEC in background
  13 #   SERVICE_WRITE_PID   create a pid-file and use it for matching
  14 #   SERVICE_MATCH_EXEC  use EXEC command-line for matching (default)
  15 #   SERVICE_MATCH_NAME  use EXEC process name for matching
  16 #   SERVICE_USE_PID     assume EXEC create its own pid-file and use it for matching
  17 #   SERVICE_NAME        process name to use (default to EXEC file part)
  18 #   SERVICE_PID_FILE    pid file to use (default to /var/run/$SERVICE_NAME.pid)
  19 #   SERVICE_SIG         signal to send when using -K
  20 #   SERVICE_SIG_RELOAD  default signal used when reloading
  21 #   SERVICE_SIG_STOP    default signal used when stopping
  22 #   SERVICE_STOP_TIME   time to wait for a process to stop gracefully before killing it
  23 #   SERVICE_UID         user EXEC should be run as
  24 #   SERVICE_GID         group EXEC should be run as
  25 #
  26 #   SERVICE_DEBUG       don't do anything, but show what would be done
  27 #   SERVICE_QUIET       don't print anything
  28 #
  29
  30 SERVICE_QUIET=1
  31 SERVICE_SIG_RELOAD="HUP"
  32 SERVICE_SIG_STOP="TERM"
  33 SERVICE_STOP_TIME=5
  34 SERVICE_MATCH_EXEC=1
  35
  36 service() {
  37         local ssd
  38         local exec
  39         local name
  40         local start
  41         ssd="${SERVICE_DEBUG:+echo }start-stop-daemon${SERVICE_QUIET:+ -q}"
  42         case "$1" in
  43           -C)
  44                 ssd="$ssd -K -t"
  45                 ;;
  46           -S)
  47                 ssd="$ssd -S${SERVICE_DAEMONIZE:+ -b}${SERVICE_WRITE_PID:+ -m}"
  48                 start=1
  49                 ;;
  50           -K)
  51                 ssd="$ssd -K${SERVICE_SIG:+ -s $SERVICE_SIG}"
  52                 ;;
  53           *)
  54                 echo "service: unknown ACTION '$1'" 1>&2
  55                 return 1
  56         esac
  57         shift
  58         exec="$1"
  59         [ -n "$exec" ] || {
  60                 echo "service: missing argument" 1>&2
  61                 return 1
  62         }
  63         [ -x "$exec" ] || {
  64                 echo "service: file '$exec' is not executable" 1>&2
  65                 return 1
  66         }
  67         name="${SERVICE_NAME:-${exec##*/}}"
  68         [ -z "$SERVICE_USE_PID$SERVICE_WRITE_PID$SERVICE_PID_FILE" ] \
  69                 || ssd="$ssd -p ${SERVICE_PID_FILE:-/var/run/$name.pid}"
  70         [ -z "$SERVICE_MATCH_NAME" ] || ssd="$ssd -n $name"
  71         ssd="$ssd${SERVICE_UID:+ -c $SERVICE_UID${SERVICE_GID:+:$SERVICE_GID}}"
  72         [ -z "$SERVICE_MATCH_EXEC$start" ] || ssd="$ssd -x $exec"
  73         shift
  74         $ssd${1:+ -- "$@"}
  75 }
  76
  77 service_check() {
  78         service -C "$@"
  79 }
  80
  81 service_signal() {
  82         SERVICE_SIG="${SERVICE_SIG:-USR1}" service -K "$@"
  83 }
  84
  85 service_start() {
  86         service -S "$@"
  87 }
  88
  89 service_stop() {
  90         local try
  91         SERVICE_SIG="${SERVICE_SIG:-$SERVICE_SIG_STOP}" service -K "$@" || return 1
  92         while [ $((try++)) -lt $SERVICE_STOP_TIME ]; do
  93                 service -C "$@" || return 0
  94                 sleep 1
  95         done
  96         SERVICE_SIG="KILL" service -K "$@"
  97         sleep 1
  98         ! service -C "$@"
  99 }
 100
 101 service_reload() {
 102         SERVICE_SIG="${SERVICE_SIG:-$SERVICE_SIG_RELOAD}" service -K "$@"
 103 }