From 2b72e15884c90cf9bab5950695ceeefc1bb9e93a Mon Sep 17 00:00:00 2001
From: fbt <fbt@fleshless.org>
Date: Sun, 13 Nov 2016 11:11:47 +0300
Subject: [PATCH] init

Signed-off-by: fbt <fbt@fleshless.org>
---
 sm | 264 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 264 insertions(+)
 create mode 100755 sm

diff --git a/sm b/sm
new file mode 100755
index 0000000..ef87b1a
--- /dev/null
+++ b/sm
@@ -0,0 +1,264 @@
+#!/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' "$2" || die 15
+		}
+	fi
+}
+
+main "$@"