Signed-off-by: fbt <fbt@fleshless.org>
This commit is contained in:
Jack L. Frost 2016-11-13 11:11:47 +03:00
commit 2b72e15884
1 changed files with 264 additions and 0 deletions

264
sm Executable file
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#!/usr/bin/env bash
shopt -s nullglob
# Utility functions
## Make setting default values a bit less awkward
default() {
declare -n _p=$1
if ! [[ "$_p" ]]; then
_p=$2
fi
}
## Die. Why not?
die() {
declare code=${1:-0}
[[ "$2" ]] && printf '%s\n' "$2"
exit "$code"
}
## Run the command and wait for it to die
svc() {
svc::cleanup() {
kill -n "$service_stop_signal" "$service_pid"
pid_wait "$service_pid" && {
rm -f $svc_pidfile
}
}; trap 'svc::cleanup' TERM INT
svc::reload() {
kill -n "$service_reload_signal" "$service_pid"
}; trap 'svc::reload' HUP
exec "$@" &
service_pid=$!
wait
}
## Respawn implementation
respawn() {
declare jpid
respawn::cleanup() {
kill -n 15 0
wait
exit 0
}; trap 'svc::reload' TERM
while true; do
"$@" & jpid=$!
wait
done
}
## Run a command with its output discarded
nullexec() {
"$@" &>/dev/null
}
## Wait for a pid to die
pid_wait() {
declare cnt=0
while nullexec kill -0 "$1"; do
(( cnt >= service_stop_timeout )) && return 1
sleep 1
(( cnt++ ))
done
return 0
}
## See if NAME is a function
is_function() {
declare name=$1 name_tupe
name_type=$( type -t "$name" )
if [[ $name_type == 'function' ]]; then
return 0
fi
return 1
}
# DSL
depends() {
service_depends=( "$@" )
}
# Super functions
## Start the service, write down the svc pid
super_start() {
(( service_running )) && return 3
if (( service_managed )); then
if (( service_respawn )); then
svc respawn "${service_command[@]}" &>"$service_logfile" &
else
svc "${service_command[@]}" &>"$service_logfile" &
fi
svc_pid=$!
printf '%s' "$svc_pid" > "$svc_pidfile"
else
"${service_command[@]}" &
fi
return 0
}
## Reload the service
## Usually just sends HUP
super_reload() {
(( service_running )) || return 3
kill -n 1 "$service_pid"
}
## Stop the service
## Returns:
## 3: Service is not running.
super_stop() {
(( service_running )) || return 3
nullexec kill -n "$service_stop_signal" "$service_pid" || return 1
pid_wait "$service_pid" || return 5
return 0
}
# Overloadable functions
start() { super_start; }
stop() { super_stop; }
restart() {
"$0" "$service_name" stop
"$0" "$service_name" start
}
# Code
main() {
# Let's set some defaults
service_managed=1
if (( $UID )); then
# XDG stuff
default XDG_CONFIG_HOME "$HOME/.config"
default XDG_RUNTIME_DIR "/run/user/$UID"
cfgdir="$XDG_CONFIG_HOME/sm"
rundir="$XDG_RUNTIME_DIR/sm"
logdir="$HOME/log/sm"
else
cfgdir='/etc/sm'
rundir='/run/sm'
logdir='/var/log/sm'
fi
# Load custom functions
for f in "$cfgdir/functions"/*; do
source "$f" || die 9 "Failed to source functions from $f"
done
# Now create the needed runtime stuff
for d in "$rundir" "$logdir"; do
mkdir -p "$d" || die 3 "Failed to create runtime dir: $d"
done
# service_name is just $1
service_name=$1
# Semi-hardcoded stuff
svc_pidfile="$rundir/$service_name.pid"
# Get the service defaults
[[ -f "$cfgdir/conf.d/$1" ]] && {
source "$cfgdir/conf.d/$1" || die 5 "Failed to read service defaults: $cfgdir/conf.d/$1"
}
# Get the service config
source "$cfgdir/init.d/$1" || die 7 "Failed to read the service config: $cfgdir/init.d/$1"
# Legacy
[[ "$service_args" ]] && service_command=( "${service_command[@]}" "${service_args[@]}" )
[[ "$service_respawn" == 'true' ]] && service_respawn=1
[[ "$service_pidfile" ]] && service_managed=0
if ! (( service_managed )); then
(( service_respawn )) && die 21 "Refusing to respawn a service that manages itself."
fi
# Service-level defaults
default service_pidfile "$svc_pidfile"
default service_logfile "$logdir/$service_name.log"
default service_stop_timeout 30
default service_stop_signal 15
default service_reload_signal 1
# Let's see if there's a PID
if [[ -f "$service_pidfile" ]]; then
service_pid=$(<$service_pidfile)
# Let's see if it's running
if nullexec kill -0 "$service_pid"; then
service_running=1
fi
fi
# Check if action is even defined
is_function "$2" || die 17 "Function $2 is not defined for $service_name."
# Run pre_$action function
if is_function "pre_$2"; then
"pre_$2" || {
printf 'pre_%s failed!\n' "$2" || die 13
}
fi
# Run the function
case "$2" in
stop)
printf 'Stopping %s... ' "$service_name"
stop
case "$?" in
0) printf 'ok.\n';;
3) printf 'not running.\n' "$service_name";;
5) printf 'timed out.\n';;
*) printf 'fail.\n';;
esac
;;
start)
printf 'Starting %s... ' "$service_name"
start
case "$?" in
0) printf 'ok.\n';;
3) printf 'already running.\n';;
*) printf 'fail.\n';;
esac
;;
*) "$2";;
esac
# Run post_$action function
if is_function "post_$2"; then
"post_$2" || {
printf 'post_%s failed!\n' "$2" || die 15
}
fi
}
main "$@"