lfs-book-zh_CN/bootscripts/contrib/lsb-v3/init.d/lfs-functions

# Begin /etc/init.d/lfs-functions
# Provides LFS specific functions for LSB style bootscripts

################################# chkstat() ###################################
# chk_stat checks the status of a script by checking for both a binary file   #
# to execute, and if set, a config file that may be needed for the program    #
# to run successfully.  The calling script will exit with a return value of 5 #
# if the binary does not exist, and a value of 6 if the needed config file is #
# unavailable as per LSB requirements.  This function accepts zero, one, or   #
# two string arguments.  If arguments are passed, the first must be a bin     #
# file.  If a second argument is passed, it is interpreted as the config      #
# file.  Optionally, zero arguments can be passed if BIN_FILE, and optinally  #
# CONFIG_FILE are set in the calling script.                                  #
###############################################################################
chk_stat()
{
    if [ "${#}" -gt "0" -a "${#}" -lt "3" ]; then
        BIN_FILE="${1}"
        if [ -z "${2}" ]; then
            CONFIG_FILE=""
        else
            CONFIG_FILE="${2}"
        fi
    elif [ -z "${BIN_FILE}" ]; then
            echo "Usage: 'chk_stat BIN_FILE CONFIG_FILE'"
            exit 1 # Generic Error
    fi

    if [ ! -e "${BIN_FILE}" ]; then
        log_failure_msg "${BIN_FILE} not installed" &&
        exit 5
    fi

    if [ ! -z "${CONFIG_FILE}" ]; then
        if [ ! -e "${CONFIG_FILE}" ]; then
            log_failure_msg "${CONFIG_FILE} does not exist" &&
            exit 6
        fi
    fi
}

################################ loadproc() ###################################
# loadproc is just a wraper to start_daemon for simple scripts, which will    #
# require no arguments if $BIN_FILE is set.                                   #
###############################################################################
loadproc()
{
    start_daemon "${BIN_FILE}" "${@}"
}

################################ endproc() ####################################
# endproc, like loadproc, is just a wraper to killproc for simplicity and is  #
# dependent on $BIN_FILE being set.                                           #
###############################################################################
endproc()
{
    killproc "${BIN_FILE}" "${@}"
}

############################### statusproc() ##################################
# statusproc checks the status of a particular binary and displays the        #
# appropriate message (running or not running) and exits on the return value  #
# of pidofproc.  This function accepts two string arguments or zero arguments #
# if BIN_FILE and MESSAGE are set, else it requires the bin file as the first #
# argument, and the message as the second.  Both must be enclosed in quotes.  #
###############################################################################
statusproc()
{
    if [ "${#}" -gt "0" -a "${#}" -lt "3" ]; then
        BIN_FILE="${1}"
        MESSAGE="${2}"
    elif [ -z "${BIN_FILE}" -o -z "${MESSAGE}" ]; then
        echo "Usage: 'statusproc BIN_FILE MESSAGE'"
        exit 1 # Generic Error
    fi

    pidlist=`pidofproc "${BIN_FILE}"`
    STATUS=$?
    echo "Checking ${MESSAGE} status:"
    if [ "${STATUS}" = "0" ]; then
        log_success_msg "Running with PID(s) ${pidlist}"
    else
        log_warning_msg "Not running!"
    fi

    return "${STATUS}"
}

############################### reloadproc() ##################################
# reloadproc sends a HUP signal to the running program (relaod configuration) #
# It optionally, using the -force switch, checks the status of a particular   #
# program and starts it if it is not already running. This function accepts   #
# one optional switch (must be the first argument), and either two, or zero   #
# string arguments.  If BIN_FILE and MESSAGE are set in the script's          #
# environment, it will use those values,  else it requires the bin file as    #
# the first argument (following -force if used), and the message as the       #
# second. Both must be enclosed in quotes. If the force option is used, it    #
# follows the LSB definition of 'force-reload' - the program is started if    #
# not already running.                                                        #
###############################################################################
reloadproc()
{
    local force="0"
    if [ "${#}" -gt "0" -a "${1}" = "-force" ]; then
        force="1"
        shift 1
    fi

    if [ "${#}" -gt "0" -a "${#}" -lt "3" ]; then
        BIN_FILE="${1}"
        MESSAGE="${2}"
    elif [ -z "${BIN_FILE}" -o -z "${MESSAGE}" ]; then
        echo "Usage: 'reloadproc BIN_FILE MESSAGE'"
        exit 1 # Generic Error
    fi

    

}

############################## evaluate_retval() ###############################
# evaluate_retval requires that you pass exactly one evaluation parameter of   #
# (start, stop, other) based on the previous action that is being evaluated.   #
# This function is intended for use with start_daemon and killproc to          #
# interpret the LSB exit codes properly, othewise the checks only for success  #
# or failure.                                                                  #
################################################################################
evaluate_retval()
{
    local error_value="${?}"

    # Handle LSB defined return values
    case "${1}" in

      start)
        case "${error_value}" in
          0)
            log_success_msg "Starting ${MESSAGE} "
            return "${error_value}"
          ;;
          2)
            log_failure_msg "Starting ${MESSAGE} Error: Invalid argument!"
            return "${error_value}"
          ;;
          5)
            log_failure_msg "Starting ${MESSAGE} Error: Not available!"
            return "${error_value}"
          ;;
          *)
            log_failure_msg "Starting ${MESSAGE} Error: General failure!"
            return "${error_value}"
          ;;
        esac
      ;;

      stop)
        case "${error_value}" in
          0)
            log_success_msg "Stopping ${MESSAGE} "
            return "${error_value}"
            ;;
          2)
            log_failure_msg "Stopping ${MESSAGE} Error: Invalid argument!"
            return "${error_value}"
            ;;
          5)
            log_failure_msg "Stopping ${MESSAGE} Error: Not available!"
            return "${error_value}"
            ;;
          7)
            log_warning_msg "Stopping ${MESSAGE} Warning: Not running!"
            return "${error_value}"
            ;;
          *)
            log_failure_msg "Stopping ${MESSAGE} Error: General failure!"
            return "${error_value}"
            ;;
          esac
       ;;

       force-reload)
         message="Forcefully reloading "
       ;;

       reload)
         message="Reloading "
       ;;

       restart)
         message="Restarting "
       ;;

       try-restart)
         message="Trying restart "
       ;;

       standard)
         # $message or $MESSAGE must be set, but not both in order
         # to use the 'standard' target.
       ;;
    esac

    # Print messages for the generic force-reload, reload, restart, 
    # and try-restart targets
    if [ "${error_value}" = "0" ]
    then
        log_success_msg "${message}${MESSAGE} "
        return "${error_value}"
    else
        log_failure_msg "${message}${MESSAGE} "
        return "${error_value}"
    fi
}