servicectl

#!/bin/bash
# Control services for system based on Systemd inside chroot and SysVinit outside chroot
# https://github.com/smaknsk/servicectl
#

# Pach systemd services file
SYSTEMD_UNITS_PATH="/lib/systemd/system/"

# Path contents symlink on systemd units files
SERVICECTL_ENABLED_PATH="/etc/init.d-chroot/"

# Check is root
if [ $EUID -ne 0 ]; then
  echo "You must run as root user" 2>&1
  exit 1
fi

# Parse ini file. usage: parse $inifile $section $key
# Return 0 on success, 1 if file cannot be opened, 2 if the given key cannot be found in the given section
function parse()
{
  local _inifile=$1
  local _section=$2
  local _key=$3

   if [ ! -r "$_inifile" ]
   then
     exit 1;
   fi        

   exec < $_inifile

   while read section; do
     if [ "$section" = '['$_section']' ] ; then
       IFS='='
       while read key value; do
         # check if we are still within our section
         if [ `echo -n $key | grep "^\s*\[.*\]\s*$"` ]; then
            exit 2;
         fi
         # strip leading and trailing whitespace from keys
         key=`echo -n "$key" | sed 's/^\s*//;s/\s*$//'`
         _key=`echo -n "$_key" | sed 's/^\s*//;s/\s*$//'`
         if [ "$key" = "$_key" ]; then
           echo $value
           exit 0;
         fi
      done
    fi
  done
  exit 2;
}

# Execute action from systemd service file
function exec_action() {
    local action=$1
    local service=$2
    local file="${SYSTEMD_UNITS_PATH}${service}.service"
    local is_required=1 # by default turn action is required
    local cmd=""
        
    # if passed arg $3 then set value
    if [[ -n $3 ]]; then
        local is_required=$3
    fi

    cmd=`parse $file Service $action`
    local ret=$?    
    if [ $ret = 1 ]; then
        echo "Error: file $file cannot be opened"
        return 1
    fi
    if [ $ret = 2 ]; then
    
        # if action required, return error
        if [ $is_required = 1 ]; then
            echo "Error: action $action not found in file $file"
            return 1
        fi
        
        return 0        
    fi
  
    eval $cmd
    return $?
}

function exec_if_exists() {
    exec_action $@ 0
}

function exec_stop() {
    local service=$1
    local file="${SYSTEMD_UNITS_PATH}${service}.service"
    local cmd=""
    
    cmd=`parse $file Service ExecStop`
    local ret=$?
    
    # if ExecStop exists
    if [ $ret = 0 ]; then
        exec_action ExecStop $service
        return $?
    fi
    
    # get path pid file
    pid_file=`parse $file Service PIDFile`
    local ret=$?
    if [ $ret != 0 ]; then
        echo "Error: attribute PIDFile not exists in file $file"
        return 1
    fi

    read PID < $pid_file
    kill -TERM "$PID" || echo "Couldn't kill PID"
}

if [[ -z ${@:2} ]]; then
    echo "Error: you must specify the service"
    exit 1
fi

# Switch action
case "$1" in
    start)
        for service in ${@:2} 
        do
            service=${service%".service"}
            exec_if_exists ExecStartPre $service
            if [ $? = 0 ]; then
                exec_action ExecStart $service
            fi
        done
    ;;
    
    stop)
        for service in ${@:2} 
        do
            service=${service%".service"}
            exec_stop $service
        done
    ;;
    
    restart)
        for service in ${@:2} 
        do
            service=${service%".service"}
            exec_stop $service
            exec_action ExecStart $service
        done
    ;;
    
    reload)
        for service in ${@:2} 
        do
            service=${service%".service"}
            exec_action ExecReload $service
        done
    ;;

    enable)
        for service in ${@:2} 
        do
            service=${service%".service"}
            file="${SYSTEMD_UNITS_PATH}${service}.service"
            enabled_symlink="${SERVICECTL_ENABLED_PATH}${service}.service"

            if [ ! -f "$file" ]; then
                echo "Error: file $file is not exists"
                continue
            fi

            if [ -f "$enabled_symlink" ]; then
                echo "${service} already enabled"
                continue
            fi

            echo "ln -s \"$file\" \"$enabled_symlink\""
            ln -s "$file" "$enabled_symlink"
        done
    ;;

    disable)
        for service in ${@:2} 
        do
            service=${service%".service"}
            file="${SERVICECTL_ENABLED_PATH}${service}.service"
            if [ ! -f "$file" ]; then
                echo "Error: file $file is not exists"
                continue
            fi
            
            echo "rm $file"
            rm $file
        done
    ;;
    
    *)
        echo "Available actions: start, stop, restart, reload, enable or disable"
        exit 1
    ;;
esac