lfs-book-zh_CN/bootscripts/lfs/init.d/functions

#!/bin/sh
########################################################################
# Begin boot functions
#
# Description : Run Level Control Functions
#
# Authors     : Gerard Beekmans - gerard@linuxfromscratch.org
# Update      : Bruce Dubbs - bdubbs@linuxfromscratch.org
#
# Version     : LFS 7.0
#
# Notes       : With code based on Matthias Benkmann's simpleinit-msb
#               http://winterdrache.de/linux/newboot/index.html
#
#               The file should be located in /lib/boot
#
########################################################################

# Set any needed environment variables e.g. HEADLESS
[ -r /etc/sysconfig/init_params ]  && . /etc/sysconfig/init_params

## Environmental setup
# Setup default values for environment
umask 022
export PATH="/bin:/usr/bin:/sbin:/usr/sbin"

# Signal sent to running processes to refresh their configuration
RELOADSIG="HUP"

# Number of seconds between STOPSIG and FALLBACK when stopping processes
KILLDELAY="3"

## Screen Dimensions
# Find current screen size
if [ -z "${COLUMNS}" ]; then
   COLUMNS=$(stty size)
   COLUMNS=${COLUMNS##* }
fi

# When using remote connections, such as a serial port, stty size returns 0
if [ "${COLUMNS}" = "0" ]; then 
   COLUMNS=80
fi

## Measurements for positioning result messages
COL=$((${COLUMNS} - 8))
WCOL=$((${COL} - 2))

## Provide an echo that supports -e and -n
# If formatting is needed, $ECHO should be used
case "`echo -e -n test`" in
   -[en]*)
      ECHO=/bin/echo
      ;;
   *)
      ECHO=echo
      ;;
esac

## Set Cursor Position Commands, used via $ECHO
SET_COL="\\033[${COL}G"      # at the $COL char
SET_WCOL="\\033[${WCOL}G"    # at the $WCOL char
CURS_UP="\\033[1A\\033[0G"   # Up one line, at the 0'th char

## Set color commands, used via $ECHO
# Please consult `man console_codes for more information
# under the "ECMA-48 Set Graphics Rendition" section
#
# Warning: when switching from a 8bit to a 9bit font,
# the linux console will reinterpret the bold (1;) to
# the top 256 glyphs of the 9bit font.  This does
# not affect framebuffer consoles
NORMAL="\\033[0;39m"         # Standard console grey
SUCCESS="\\033[1;32m"        # Success is green
WARNING="\\033[1;33m"        # Warnings are yellow
FAILURE="\\033[1;31m"        # Failures are red
INFO="\\033[1;36m"           # Information is light cyan
BRACKET="\\033[1;34m"        # Brackets are blue

STRING_LENGTH="0"   # the length of the current message

#*******************************************************************************
# Function - boot_mesg()
#
# Purpose:      Sending information from bootup scripts to the console
#
# Inputs:       $1 is the message
#               $2 is the colorcode for the console
#
# Outputs:      Standard Output
#
# Dependencies: - sed for parsing strings.
#          - grep for counting string length.
#               
# Todo:         
#*******************************************************************************
boot_mesg()
{
   local ECHOPARM=""

   while true
   do
      case "${1}" in
         -n)
            ECHOPARM=" -n "
            shift 1
            ;;
         -*)
            echo "Unknown Option: ${1}"
            return 1
            ;;
         *)
            break
            ;;
      esac
   done

   ## Figure out the length of what is to be printed to be used
   ## for warning messages. 
   STRING_LENGTH=$((${#1} + 1))

   # Print the message to the screen
   ${ECHO} ${ECHOPARM} -e "${2}${1}"

   # Log the message 
   ${ECHO} ${ECHOPARM} -e "${2}${1}" >> /run/var/bootlog
}

boot_mesg_flush()
{
   # Reset STRING_LENGTH for next message
   STRING_LENGTH="0"
}

echo_ok()
{
   ${ECHO} -n -e "${CURS_UP}${SET_COL}${BRACKET}[${SUCCESS}  OK  ${BRACKET}]"
   ${ECHO} -e "${NORMAL}"
   boot_mesg_flush

   ${ECHO} -e "[ OK ]" >> /run/var/bootlog
}

echo_failure()
{
   ${ECHO} -n -e "${CURS_UP}${SET_COL}${BRACKET}[${FAILURE} FAIL ${BRACKET}]"
   ${ECHO} -e "${NORMAL}"
    boot_mesg_flush

   ${ECHO} -e "[ FAIL]"  >> /run/var/bootlog
}

echo_warning()
{
   ${ECHO} -n -e "${CURS_UP}${SET_COL}${BRACKET}[${WARNING} WARN ${BRACKET}]"
   ${ECHO} -e "${NORMAL}"
   boot_mesg_flush

   ${ECHO} -e "[ WARN ]"  >> /run/var/bootlog
}

echo_skipped()
{
   ${ECHO} -n -e "${CURS_UP}${SET_COL}${BRACKET}[${WARNING} SKIP ${BRACKET}]"
   ${ECHO} -e "${NORMAL}"
   boot_mesg_flush

   ${ECHO} -e "  [ SKIP ]" >> /run/var/bootlog
}

wait_for_user()
{
   # Wait for the user by default
   [ "${HEADLESS=0}" = "0" ] && read ENTER
}

evaluate_retval()
{
   error_value="${?}"

   if [ ${error_value} = 0 ]; then
      echo_ok
   else
      echo_failure
   fi

   # This prevents the 'An Unexpected Error Has Occurred' from trivial
   # errors.
   return 0
}

print_status()
{
   if [ "${#}" = "0" ]; then
      echo "Usage: ${0} {success|warning|failure}"
      return 1
   fi

   case "${1}" in

      success)
         echo_ok
         ;;

      warning)
         # Leave this extra case in because old scripts
         # may call it this way.
         case "${2}" in
            running)
               ${ECHO} -e -n "${CURS_UP}"
               ${ECHO} -e -n "\\033[${STRING_LENGTH}G   "
               boot_mesg "Already running." ${WARNING}
               echo_warning
               ;;
            not_running)
               ${ECHO} -e -n "${CURS_UP}"
               ${ECHO} -e -n "\\033[${STRING_LENGTH}G   "
               boot_mesg "Not running." ${WARNING}
               echo_warning
               ;;
            not_available)
               ${ECHO} -e -n "${CURS_UP}"
               ${ECHO} -e -n "\\033[${STRING_LENGTH}G   "
               boot_mesg "Not available." ${WARNING}
               echo_warning
               ;;
            *)
               # This is how it is supposed to
               # be called
               echo_warning
               ;;
         esac
      ;;

      failure)
         echo_failure
      ;;

   esac

}

reloadproc()
{
   local pidfile=""
   local failure=0

   while true
   do
      case "${1}" in
         -p)
            pidfile="${2}"
            shift 2
            ;;
         -*)
            log_failure_msg "Unknown Option: ${1}"
            return 2
            ;;
         *)
            break
            ;;
      esac
   done

   if [ "${#}" -lt "1" ]; then
      log_failure_msg "Usage: reloadproc [-p pidfile] pathname"
      return 2
   fi

   # This will ensure compatibility with previous LFS Bootscripts
   if [ -n "${PIDFILE}" ]; then
      pidfile="${PIDFILE}"
   fi

   # Is the process running?
   if [ -z "${pidfile}" ]; then
      pidofproc -s "${1}"
   else
      pidofproc -s -p "${pidfile}" "${1}"
   fi

   # Warn about stale pid file
   if [ "$?" = 1 ]; then
      boot_mesg -n "Removing stale pid file: ${pidfile}. " ${WARNING}
      rm -f "${pidfile}"
   fi

   if [ -n "${pidlist}" ]; then
      for pid in ${pidlist}
      do
         kill -"${RELOADSIG}" "${pid}" || failure="1"
      done

      (exit ${failure})
      evaluate_retval

   else
      boot_mesg "Process ${1} not running." ${WARNING}
      echo_warning
   fi
}

statusproc()
{
   local pidfile=""
   local base=""
   local ret=""

   while true
   do
      case "${1}" in
         -p)
            pidfile="${2}"
            shift 2
            ;;
         -*)
            log_failure_msg "Unknown Option: ${1}"
            return 2
            ;;
         *)
            break
            ;;
      esac
   done

   if [ "${#}" != "1" ]; then
      shift 1
      log_failure_msg "Usage: statusproc [-p pidfile] pathname"
      return 2
   fi

   # Get the process basename
   base="${1##*/}"

   # This will ensure compatibility with previous LFS Bootscripts
   if [ -n "${PIDFILE}" ]; then
      pidfile="${PIDFILE}"
   fi

   # Is the process running?
   if [ -z "${pidfile}" ]; then
      pidofproc -s "${1}"
   else
      pidofproc -s -p "${pidfile}" "${1}"
   fi

   # Store the return status
   ret=$?

   if [ -n "${pidlist}" ]; then
      ${ECHO} -e "${INFO}${base} is running with Process"\
         "ID(s) ${pidlist}.${NORMAL}"
   else
      if [ -n "${base}" -a -e "/var/run/${base}.pid" ]; then
         ${ECHO} -e "${WARNING}${1} is not running but"\
            "/var/run/${base}.pid exists.${NORMAL}"
      else
         if [ -n "${pidfile}" -a -e "${pidfile}" ]; then
            ${ECHO} -e "${WARNING}${1} is not running"\
               "but ${pidfile} exists.${NORMAL}"
         else
            ${ECHO} -e "${INFO}${1} is not running.${NORMAL}"
         fi
      fi
   fi

   # Return the status from pidofproc
   return $ret
}

# The below functions are documented in the LSB-generic 2.1.0

#*******************************************************************************
# Function - pidofproc [-s] [-p pidfile] pathname
#
# Purpose: This function returns one or more pid(s) for a particular daemon
#
# Inputs: -p pidfile, use the specified pidfile instead of pidof
#         pathname, path to the specified program
#
# Outputs: return 0 - Success, pid's in stdout
#          return 1 - Program is dead, pidfile exists
#          return 2 - Invalid or excessive number of arguments, 
#                     warning in stdout
#          return 3 - Program is not running
#
# Dependencies: pidof, echo, head
#
# Todo: Remove dependency on head
#       This replaces getpids
#       Test changes to pidof
#
#*******************************************************************************
pidofproc()
{
   local pidfile=""
   local lpids=""
   local silent=""
   pidlist=""
   while true
   do
      case "${1}" in
         -p)
            pidfile="${2}"
            shift 2
            ;;

         -s)
            # Added for legacy opperation of getpids
            # eliminates several '> /dev/null'
            silent="1"
            shift 1
            ;;
         -*)
            log_failure_msg "Unknown Option: ${1}"
            return 2
            ;;
         *)
            break
            ;;
      esac
   done

   if [ "${#}" != "1" ]; then
      shift 1
      log_failure_msg "Usage: pidofproc [-s] [-p pidfile] pathname"
      return 2
   fi

   if [ -n "${pidfile}" ]; then
      if [ ! -r "${pidfile}" ]; then
         return 3 # Program is not running
      fi

      lpids=`head -n 1 ${pidfile}`
      for pid in ${lpids}
      do
         if [ "${pid}" -ne "$$" -a "${pid}" -ne "${PPID}" ]; then
            kill -0 "${pid}" 2>/dev/null &&
            pidlist="${pidlist} ${pid}"
         fi
         
         if [ "${silent}" != "1" ]; then
            echo "${pidlist}"
         fi

         test -z "${pidlist}" && 
         # Program is dead, pidfile exists
         return 1
         # else
         return 0
      done

   else
      pidlist=`pidof -o $$ -o $PPID -x "$1"`
      if [ "${silent}" != "1" ]; then
         echo "${pidlist}"
      fi

      # Get provide correct running status
      if [ -n "${pidlist}" ]; then
         return 0
      else
         return 3
      fi

   fi

   if [ "$?" != "0" ]; then
      return 3 # Program is not running
   fi
}

#*******************************************************************************
# Function - loadproc [-f] [-n nicelevel] [-p pidfile] pathname [args]
#
# Purpose: This runs the specified program as a daemon
#
# Inputs: -f, run the program even if it is already running
#         -n nicelevel, specifies a nice level. See nice(1).
#         -p pidfile, uses the specified pidfile
#         pathname, pathname to the specified program
#         args, arguments to pass to specified program
#
# Outputs: return 0 - Success
#          return 2 - Invalid of excessive number of arguments, 
#                     warning in stdout
#          return 4 - Program or service status is unknown
#
# Dependencies: nice, rm
#
# Todo: LSB says this should be called start_daemon
#       LSB does not say that it should call evaluate_retval
#       It checks for PIDFILE, which is deprecated.
#         Will be removed after BLFS 6.0
#       loadproc returns 0 if program is already running, not LSB compliant
#
#*******************************************************************************
loadproc()
{
   local pidfile=""
   local forcestart=""
   local nicelevel="10"

# This will ensure compatibility with previous LFS Bootscripts
   if [ -n "${PIDFILE}" ]; then
      pidfile="${PIDFILE}"
   fi

  while true
   do
      case "${1}" in
         -f)
            forcestart="1"
            shift 1
            ;;
         -n)
            nicelevel="${2}"
            shift 2
            ;;
         -p)
            pidfile="${2}"
            shift 2
            ;;
         -*)
            log_failure_msg "Unknown Option: ${1}"
            return 2 #invalid or excess argument(s)
            ;;
         *)
            break
            ;;
      esac
   done

   if [ "${#}" = "0" ]; then
      log_failure_msg "Usage: loadproc [-f] [-n nicelevel] [-p pidfile] pathname [args]"
      return 2 #invalid or excess argument(s)
   fi

   if [ -z "${forcestart}" ]; then
      if [ -z "${pidfile}" ]; then
         pidofproc -s "${1}"
      else
         pidofproc -s -p "${pidfile}" "${1}"
      fi

      case "${?}" in
         0)
            log_warning_msg "Unable to continue: ${1} is running"
            return 0 # 4
            ;;
         1)
            boot_mesg "Removing stale pid file: ${pidfile}" ${WARNING}
            rm -f "${pidfile}"
            ;;
         3)
            ;;
         *)
            log_failure_msg "Unknown error code from pidofproc: ${?}"
            return 4
            ;;
      esac
   fi

   nice -n "${nicelevel}" "${@}"
   evaluate_retval # This is "Probably" not LSB compliant,
#                         but required to be compatible with older bootscripts
   return 0
}

#*******************************************************************************
# Function - killproc  [-p pidfile] pathname [signal]
#
# Purpose:
#
# Inputs: -p pidfile, uses the specified pidfile
#         pathname, pathname to the specified program
#         signal, send this signal to pathname
#
# Outputs: return 0 - Success
#          return 2 - Invalid of excessive number of arguments, 
#                     warning in stdout
#          return 4 - Unknown Status
#
# Dependencies: kill, rm
#
# Todo: LSB does not say that it should call evaluate_retval
#       It checks for PIDFILE, which is deprecated.
#         Will be removed after BLFS 6.0
#
#*******************************************************************************
killproc()
{
   local pidfile=""
   local killsig=TERM # default signal is SIGTERM
   pidlist=""

   # This will ensure compatibility with previous LFS Bootscripts
   if [ -n "${PIDFILE}" ]; then
      pidfile="${PIDFILE}"
   fi

   while true
   do
      case "${1}" in
         -p)
            pidfile="${2}"
            shift 2
            ;;
         -*)
            log_failure_msg "Unknown Option: ${1}"
            return 2
            ;;
         *)
            break
            ;;
      esac
   done

   if [ "${#}" = "2" ]; then
      killsig="${2}"
   elif [ "${#}" != "1" ]; then
      shift 2
      log_failure_msg "Usage: killproc  [-p pidfile] pathname [signal]"
      return 2
   fi

   # Is the process running?
   if [ -z "${pidfile}" ]; then
      pidofproc -s "${1}"
   else
      pidofproc -s -p "${pidfile}" "${1}"
   fi

   # Remove stale pidfile
   if [ "$?" = 1 ]; then
      boot_mesg "Removing stale pid file: ${pidfile}." ${WARNING}
      rm -f "${pidfile}"
   fi

    # If running, send the signal
    if [ -n "${pidlist}" ]; then
   for pid in ${pidlist}
   do
      kill -${killsig} ${pid} 2>/dev/null

      # Wait up to 3 seconds, for ${pid} to terminate
      case "${killsig}" in
      TERM|SIGTERM|KILL|SIGKILL)
         # sleep in 1/10ths of seconds and
         # multiply KILLDELAY by 10
         local dtime="${KILLDELAY}0"
         while [ "${dtime}" != "0" ]
         do
            kill -0 ${pid} 2>/dev/null || break
            sleep 0.1
            dtime=$(( ${dtime} - 1))
         done
         # If ${pid} is still running, kill it
         kill -0 ${pid} 2>/dev/null && kill -KILL ${pid} 2>/dev/null
         ;;
      esac
   done

   # Check if the process is still running if we tried to stop it
   case "${killsig}" in
   TERM|SIGTERM|KILL|SIGKILL)
      if [ -z "${pidfile}" ]; then
         pidofproc -s "${1}"
      else
         pidofproc -s -p "${pidfile}" "${1}"
      fi

      # Program was terminated
      if [ "$?" != "0" ]; then
         # Remove the pidfile if necessary
         if [ -f "${pidfile}" ]; then
            rm -f "${pidfile}"
         fi
         echo_ok
         return 0
      else # Program is still running
         echo_failure
         return 4 # Unknown Status
      fi
      ;;
   *)
      # Just see if the kill returned successfully
      evaluate_retval
      ;;
   esac
    else # process not running
   print_status warning not_running
    fi
}


#*******************************************************************************
# Function - log_success_msg "message"
#
# Purpose: Print a success message
#
# Inputs: $@ - Message
#
# Outputs: Text output to screen
#
# Dependencies: echo
#
# Todo: logging
#
#*******************************************************************************
log_success_msg()
{
   ${ECHO} -n -e "${BOOTMESG_PREFIX}${@}"
   ${ECHO} -e "${SET_COL}""${BRACKET}""[""${SUCCESS}""  OK  ""${BRACKET}""]""${NORMAL}"

   ${ECHO} -n -e "${@}  [ OK ]"  >> /run/var/bootlog
   return 0
}

#*******************************************************************************
# Function - log_failure_msg "message"
#
# Purpose: Print a failure message
#
# Inputs: $@ - Message
#
# Outputs: Text output to screen
#
# Dependencies: echo
#
# Todo: logging
#
#*******************************************************************************
log_failure_msg() {
   ${ECHO} -n -e "${BOOTMESG_PREFIX}${@}"
   ${ECHO} -e "${SET_COL}""${BRACKET}""[""${FAILURE}"" FAIL ""${BRACKET}""]""${NORMAL}"

   ${ECHO} -e "${@}  [ FAIL ]" >> /run/var/bootlog
   return 0
}

#*******************************************************************************
# Function - log_warning_msg "message"
#
# Purpose: print a warning message
#
# Inputs: $@ - Message
#
# Outputs: Text output to screen
#
# Dependencies: echo
#
# Todo: logging
#
#*******************************************************************************
log_warning_msg() {
   ${ECHO} -n -e "${BOOTMESG_PREFIX}${@}"
   ${ECHO} -e "${SET_COL}""${BRACKET}""[""${WARNING}"" WARN ""${BRACKET}""]""${NORMAL}"

   ${ECHO} -e "${@}  [ WARN ]" >> /run/var/bootlog
   return 0
}

#*******************************************************************************
# Function - log_skipped_msg "message"
#
# Purpose: print a message that the script was skipped
#
# Inputs: $@ - Message
#
# Outputs: Text output to screen
#
# Dependencies: echo
#
# Todo: logging
#
#*******************************************************************************
log_skipped_msg() {
   ${ECHO} -n -e "${BOOTMESG_PREFIX}${@}"
   ${ECHO} -e "${SET_COL}""${BRACKET}""[""${WARNING}"" SKIP ""${BRACKET}""]""${NORMAL}"

   ${ECHO} -e "${@}  [ SKIP ]" >> /run/var/bootlog
   return 0
}

# End boot functions