Linux Shell之init脚本与activemq init脚本设计亮点分析
上一篇博文《Linux下Apache ActiveMQ5.9的安装配置与测试》中详细叙述了activemq的安装配置和如何利用java小程序测试activemq是否正常工作。此篇文章将继续剖解activemq中的一些精华内容，从activemq的init脚本说起。init(initialization)脚本又叫服务控制脚本，可以利用此脚本启动、停止、重新启动、重新载入配置、查看运行状态等等，通常init脚本的写法遵循System V init script的写法，能够用service命令对服务或者进程进行启动、停止、重新启动、重新载入配置、查看运行状态等操作。
init脚本通常具有如下特性：
1.使用系统自带的预定义的init函数，这一套函数通常在一个文件中，根据不同的Linux发行版本文件的位置和内容也不一样，例如Ubuntu下是/lib/lsb/init-functions以及/lib/lsb/init-functions.d/下的一些子文件，CentOS下是/etc/init.d/functions。
2.参数灵活配置，既可以在init脚本中设定可变的脚本参数，也可以引入其他文件中的配置参数
3.严谨的判断逻辑，几乎能捕获并处理所有的异常，例如函数与命令的返回值检测、文件和执行文件以及参数是否存在的判断，甚至是否是softlink文件也考虑在内
4.良好的可管理性和可移植性性，可管理性体现在针对某一服务或进程多种操作，可移植性体现在将此脚本移植到其他相似系统上照样可以执行或者只需要少量的改动就能运行，例如一个更方便的例子，手动编译安装的nginx、httpd等可以直接利用yum或者apt-get安装得到的init脚本，改动一下安装路径做一下文件链接就可以用了，省却自己编写init脚本的麻烦
下面是activemq的一个init脚本的例子，该脚本有四大亮点：
亮点1：没用使用系统提供的init公共函数；
亮点2：正确处理softlink invoke可能导致的异常；
亮点3：自动导入（生成）配置文件，而且是从自身导入
亮点4：支持多实例部署，通过不同的配置文件实现多实例运行
#!/bin/sh # ------------------------------------------------------------------------ # Licensed to the Apache Software Foundation (ASF) under one or more # contributor license agreements. See the NOTICE file distributed with # this work for additional information regarding copyright ownership. # The ASF licenses this file to You under the Apache License, Version 2.0 # (the "License"); you may not use this file except in compliance with # the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # ------------------------------------------------------------------------ # # This script controls standalone Apache ActiveMQ service processes. # To ensure compatibility to macosx and cygwin we do not utilize # lsb standard infrastructure for controlling daemons like # "start-stop-daemon". # # See also http://activemq.apache.org/activemq-command-line-tools-reference.html # for additional commandline arguments # # Authors: # Marc Schoechlin <[email protected]> # ------------------------------------------------------------------------ # CONFIGURATION ACTIVEMQ_CONFIGS="/etc/default/activemq $HOME/.activemqrc" # Backup invocation parameters COMMANDLINE_ARGS="$@" # For using instances if ( basename $0 | grep "activemq-instance-" > /dev/null);then INST="`basename $0|sed 's/^activemq-instance-//;s/\.sh$//'`" ACTIVEMQ_CONFIGS="/etc/default/activemq-instance-${INST} $HOME/.activemqrc-instance-${INST}" echo "INFO: Using alternative activemq configuration files: $ACTIVEMQ_CONFIGS" fi ## START:DEFAULTCONFIG # ------------------------------------------------------------------------ # Configuration file for running Apache Active MQ as standalone provider # # This file overwrites the predefined settings of the sysv init-script # # Active MQ installation dir if [ -z "$ACTIVEMQ_HOME" ] ; then # try to find ACTIVEMQ if [ -d /opt/activemq ] ; then ACTIVEMQ_HOME=/opt/activemq fi if [ -d "${HOME}/opt/activemq" ] ; then ACTIVEMQ_HOME="${HOME}/opt/activemq" fi ## resolve links - $0 may be a link to activemq's home PRG="$0" progname=`basename "$0"` saveddir=`pwd` # need this for relative symlinks dirname_prg=`dirname "$PRG"` cd "$dirname_prg" while [ -h "$PRG" ] ; do ls=`ls -ld "$PRG"` link=`expr "$ls" : '.*-> \(.*\)$'` if expr "$link" : '.*/.*' > /dev/null; then PRG="$link" else PRG=`dirname "$PRG"`"/$link" fi done ACTIVEMQ_HOME=`dirname "$PRG"`/.. cd "$saveddir" # make it fully qualified ACTIVEMQ_HOME=`cd "$ACTIVEMQ_HOME" && pwd` fi if [ -z "$ACTIVEMQ_BASE" ] ; then ACTIVEMQ_BASE="$ACTIVEMQ_HOME" fi # Active MQ configuration directory if [ -z "$ACTIVEMQ_CONF" ] ; then # For backwards compat with old variables we let ACTIVEMQ_CONFIG_DIR set ACTIVEMQ_CONF if [ -z "$ACTIVEMQ_CONFIG_DIR" ] ; then ACTIVEMQ_CONF="$ACTIVEMQ_BASE/conf" else ACTIVEMQ_CONF="$ACTIVEMQ_CONFIG_DIR" fi fi # Configure a user with non root priviledges, if no user is specified do not change user if [ -z "$ACTIVEMQ_USER" ] ; then ACTIVEMQ_USER="" fi # Active MQ data directory if [ -z "$ACTIVEMQ_DATA" ] ; then # For backwards compat with old variables we let ACTIVEMQ_DATA_DIR set ACTIVEMQ_DATA if [ -z "$ACTIVEMQ_DATA_DIR" ] ; then ACTIVEMQ_DATA="$ACTIVEMQ_BASE/data" else ACTIVEMQ_DATA="$ACTIVEMQ_DATA_DIR" fi fi if [ -z "$ACTIVEMQ_TMP" ] ; then ACTIVEMQ_TMP="$ACTIVEMQ_BASE/tmp" fi setCurrentUser(){ CUSER=`whoami 2>/dev/null` # Solaris fix if [ ! $? -eq 0 ]; then CUSER=`/usr/ucb/whoami 2>/dev/null` fi } if [ ! -d "$ACTIVEMQ_DATA" ]; then setCurrentUser if ( [ -z "$ACTIVEMQ_USER" ] || [ "$ACTIVEMQ_USER" = "$CUSER" ] );then mkdir $ACTIVEMQ_DATA elif [ "`id -u`" = "0" ];then su -c "mkdir $ACTIVEMQ_DATA" - $ACTIVEMQ_USER; fi fi # Location of the pidfile if [ -z "$ACTIVEMQ_PIDFILE" ]; then ACTIVEMQ_PIDFILE="$ACTIVEMQ_DATA/activemq-`hostname`.pid" fi # Location of the java installation # Specify the location of your java installation using JAVA_HOME, or specify the # path to the "java" binary using JAVACMD # (set JAVACMD to "auto" for automatic detection) #JAVA_HOME="" JAVACMD="auto" # Set jvm memory configuration if [ -z "$ACTIVEMQ_OPTS_MEMORY" ] ; then ACTIVEMQ_OPTS_MEMORY="-Xms1G -Xmx1G" fi # Uncomment to enable audit logging #ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS -Dorg.apache.activemq.audit=true" # Set jvm jmx configuration # This enables jmx access over a configured jmx-tcp-port. # You have to configure the first four settings if you run a ibm jvm, caused by the # fact that IBM's jvm does not support VirtualMachine.attach(PID). # JMX access is needed for quering a running activemq instance to gain data or to # trigger management operations. # # Example for ${ACTIVEMQ_CONF}/jmx.access: # --- # # The "monitorRole" role has readonly access. # # The "controlRole" role has readwrite access. # monitorRole readonly # controlRole readwrite # --- # # Example for ${ACTIVEMQ_CONF}/jmx.password: # --- # # The "monitorRole" role has password "abc123". # # # The "controlRole" role has password "abcd1234". # monitorRole abc123 # controlRole abcd1234 # --- # # ACTIVEMQ_SUNJMX_START="-Dcom.sun.management.jmxremote.port=11099 " # ACTIVEMQ_SUNJMX_START="$ACTIVEMQ_SUNJMX_START -Dcom.sun.management.jmxremote.password.file=${ACTIVEMQ_CONF}/jmx.password" # ACTIVEMQ_SUNJMX_START="$ACTIVEMQ_SUNJMX_START -Dcom.sun.management.jmxremote.access.file=${ACTIVEMQ_CONF}/jmx.access" # ACTIVEMQ_SUNJMX_START="$ACTIVEMQ_SUNJMX_START -Dcom.sun.management.jmxremote.ssl=false" ACTIVEMQ_SUNJMX_START="$ACTIVEMQ_SUNJMX_START -Dcom.sun.management.jmxremote" # Set jvm jmx configuration for controlling the broker process # You only have to configure the first four settings if you run a ibm jvm, caused by the # fact that IBM's jvm does not support VirtualMachine.attach(PID) # (see also com.sun.management.jmxremote.port, .jmx.password.file and .jmx.access.file ) #ACTIVEMQ_SUNJMX_CONTROL="--jmxurl service:jmx:rmi:///jndi/rmi://127.0.0.1:1099/jmxrmi --jmxuser controlRole --jmxpassword abcd1234" ACTIVEMQ_SUNJMX_CONTROL="" # Specify the queue manager URL for using "browse" option of sysv initscript if [ -z "$ACTIVEMQ_QUEUEMANAGERURL" ]; then ACTIVEMQ_QUEUEMANAGERURL="--amqurl tcp://localhost:61616" fi # Set additional JSE arguments ACTIVEMQ_SSL_OPTS="$SSL_OPTS" # Uncomment to enable YourKit profiling #ACTIVEMQ_DEBUG_OPTS="-agentlib:yjpagent" # Uncomment to enable remote debugging #ACTIVEMQ_DEBUG_OPTS="-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=5005" # ActiveMQ tries to shutdown the broker by jmx, # after a specified number of seconds send SIGKILL if [ -z "$ACTIVEMQ_KILL_MAXSECONDS" ]; then ACTIVEMQ_KILL_MAXSECONDS=30 fi ## END:DEFAULTCONFIG # ------------------------------------------------------------------------ # LOAD CONFIGURATION # load activemq configuration CONFIG_LOAD="no" for ACTIVEMQ_CONFIG in $ACTIVEMQ_CONFIGS;do if [ -f "$ACTIVEMQ_CONFIG" ] ; then ( . $ACTIVEMQ_CONFIG >/dev/null 2>&1 ) if [ "$?" != "0" ];then echo "ERROR: There are syntax errors in '$ACTIVEMQ_CONFIG'" exit 1 else echo "INFO: Loading '$ACTIVEMQ_CONFIG'" . $ACTIVEMQ_CONFIG CONFIG_LOAD="yes" fi fi done # inform user that default configuration is loaded, no suitable configfile found if [ "$CONFIG_LOAD" != "yes" ];then if [ "$1" != "setup" ];then echo "INFO: Using default configuration"; echo "(you can configure options in one of these file: $ACTIVEMQ_CONFIGS)" echo echo "INFO: Invoke the following command to create a configuration file" CONFIGS=`echo $ACTIVEMQ_CONFIGS|sed 's/[ ][ ]*/ | /'` echo "$0 setup [ $CONFIGS ]" echo fi fi if [ -z "$ACTIVEMQ_OPTS" ] ; then ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS_MEMORY -Djava.util.logging.config.file=logging.properties -Dhawtio.realm=activemq -Dhawtio.role=admins -Dhawtio.rolePrincipalClasses=org.apache.activemq.jaas.GroupPrincipal -Djava.security.auth.login.config=$ACTIVEMQ_CONF/login.config" fi # create configuration if requested if [ "$1" = "setup" ];then if [ -z "$2" ];then echo "ERROR: Specify configuration file" exit 1 fi echo "INFO: Creating configuration file: $2" ( P_STATE="0" while read LINE ;do if (echo "$LINE" | grep "START:DEFAULTCONFIG" >/dev/null );then P_STATE="1" continue; fi if (echo "$LINE" | grep "END:DEFAULTCONFIG" >/dev/null);then P_STATE="0" break; fi if [ "$P_STATE" -eq "1" ];then echo $LINE fi done < $0 ) > $2 setCurrentUser echo "INFO: It's recommend to limit access to '$2' to the priviledged user" echo "INFO: (recommended: chown '$CUSER':nogroup '$2'; chmod 600 '$2')" exit $? fi # ------------------------------------------------------------------------ # OS SPECIFIC SUPPORT OSTYPE="unknown" case "`uname`" in CYGWIN*) OSTYPE="cygwin" ;; Darwin*) OSTYPE="darwin" if [ -z "$JAVA_HOME" ] && [ "$JAVACMD" = "auto" ];then JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Home fi ;; esac # For Cygwin, ensure paths are in UNIX format before anything is touched if [ "$OSTYPE" = "cygwin" ]; then [ -n "$ACTIVEMQ_HOME" ] && ACTIVEMQ_HOME="`cygpath --unix "$ACTIVEMQ_HOME"`" [ -n "$JAVA_HOME" ] && JAVA_HOME="`cygpath --unix "$JAVA_HOME"`" [ -n "$CLASSPATH" ] && CLASSPATH="`cygpath --path --unix "$CLASSPATH"`" fi # Detect the location of the java binary if [ -z "$JAVACMD" ] || [ "$JAVACMD" = "auto" ] ; then if [ -n "$JAVA_HOME" ] ; then if [ -x "$JAVA_HOME/jre/sh/java" ] ; then # IBM's JDK on AIX uses strange locations for the executables JAVACMD="$JAVA_HOME/jre/sh/java" else JAVACMD="$JAVA_HOME/bin/java" fi fi fi # Hm, we still do not know the location of the java binary if [ ! -x "$JAVACMD" ] ; then JAVACMD=`which java 2> /dev/null ` if [ -z "$JAVACMD" ] ; then JAVACMD=java fi fi # Stop here if no java installation is defined/found if [ ! -x "$JAVACMD" ] ; then echo "ERROR: Configuration variable JAVA_HOME or JAVACMD is not defined correctly." echo " (JAVA_HOME='$JAVAHOME', JAVACMD='$JAVACMD')" exit 1 fi echo "INFO: Using java '$JAVACMD'" if [ -z "$ACTIVEMQ_BASE" ] ; then ACTIVEMQ_BASE="$ACTIVEMQ_HOME" fi # For Cygwin, switch paths to Windows format before running java if [ "$OSTYPE" = "cygwin" ]; then if [ "$OSTYPE" = "cygwin" ];then ACTIVEMQ_HOME=`cygpath --windows "$ACTIVEMQ_HOME"` ACTIVEMQ_BASE=`cygpath --windows "$ACTIVEMQ_BASE"` ACTIVEMQ_CONF=`cygpath --windows "$ACTIVEMQ_CONF"` ACTIVEMQ_DATA=`cygpath --windows "$ACTIVEMQ_DATA"` ACTIVEMQ_CLASSPATH=`cygpath --path --windows "$ACTIVEMQ_CLASSPATH"` JAVA_HOME=`cygpath --windows "$JAVA_HOME"` CLASSPATH=`cygpath --path --windows "$CLASSPATH"` CYGHOME=`cygpath --windows "$HOME"` ACTIVEMQ_TMP=`cygpath --windows "$ACTIVEMQ_TMP"` if [ -n "$CYGHOME" ]; then ACTIVEMQ_CYGWIN="-Dcygwin.user.home=\"$CYGHOME\"" fi fi # Set default classpath # Add instance conf dir before AMQ install conf dir to pick up instance-specific classpath entries first ACTIVEMQ_CLASSPATH="${ACTIVEMQ_CONF};${ACTIVEMQ_CLASSPATH}" # Start the ActiveMQ JAR # # # @ARG1 : the name of the PID-file # If specified, this function starts the java process in background as a daemon # and stores the pid of the created process in the file. # Output on stdout/stderr will be supressed if this parameter is specified # @RET : If unless 0 something went wrong # # Note: This function uses a lot of globally defined variables # - if $ACTIVEMQ_USER is set, the function tries starts the java process whith the specified # user invokeJar(){ PIDFILE="$1" RET="1" if [ ! -f "${ACTIVEMQ_HOME}/bin/activemq.jar" ];then echo "ERROR: '${ACTIVEMQ_HOME}/bin/activemq.jar' does not exist" exit 1 fi setCurrentUser if ( [ -z "$ACTIVEMQ_USER" ] || [ "$ACTIVEMQ_USER" = "$CUSER" ] );then DOIT_PREFIX="sh -c " DOIT_POSTFIX=";" elif [ "`id -u`" = "0" ];then DOIT_PREFIX="su -c " DOIT_POSTFIX=" - $ACTIVEMQ_USER" echo "INFO: changing to user '$ACTIVEMQ_USER' to invoke java" fi # Execute java binary if [ -n "$PIDFILE" ] && [ "$PIDFILE" != "stop" ];then $DOIT_PREFIX "$JAVACMD $ACTIVEMQ_OPTS $ACTIVEMQ_DEBUG_OPTS \ -Dactivemq.classpath=\"${ACTIVEMQ_CLASSPATH}\" \ -Dactivemq.home=\"${ACTIVEMQ_HOME}\" \ -Dactivemq.base=\"${ACTIVEMQ_BASE}\" \ -Dactivemq.conf=\"${ACTIVEMQ_CONF}\" \ -Dactivemq.data=\"${ACTIVEMQ_DATA}\" \ $ACTIVEMQ_CYGWIN \ -jar \"${ACTIVEMQ_HOME}/bin/activemq.jar\" $COMMANDLINE_ARGS >/dev/null 2>&1 & RET=\"\$?\"; APID=\"\$!\"; echo \$APID > $PIDFILE; echo \"INFO: pidfile created : '$PIDFILE' (pid '\$APID')\";exit \$RET" $DOIT_POSTFIX RET="$?" elif [ -n "$PIDFILE" ] && [ "$PIDFILE" = "stop" ];then PID=`cat $ACTIVEMQ_PIDFILE` $DOIT_PREFIX "$JAVACMD $ACTIVEMQ_OPTS $ACTIVEMQ_DEBUG_OPTS \ -Dactivemq.classpath=\"${ACTIVEMQ_CLASSPATH}\" \ -Dactivemq.home=\"${ACTIVEMQ_HOME}\" \ -Dactivemq.base=\"${ACTIVEMQ_BASE}\" \ -Dactivemq.conf=\"${ACTIVEMQ_CONF}\" \ -Dactivemq.data=\"${ACTIVEMQ_DATA}\" \ $ACTIVEMQ_CYGWIN \ -jar \"${ACTIVEMQ_HOME}/bin/activemq.jar\" $COMMANDLINE_ARGS --pid $PID & RET=\"\$?\"; APID=\"\$!\"; echo \$APID > $ACTIVEMQ_DATA/stop.pid; exit \$RET" $DOIT_POSTFIX RET="$?" else $DOIT_PREFIX "$JAVACMD $ACTIVEMQ_OPTS $ACTIVEMQ_DEBUG_OPTS \ -Dactivemq.classpath=\"${ACTIVEMQ_CLASSPATH}\" \ -Dactivemq.home=\"${ACTIVEMQ_HOME}\" \ -Dactivemq.base=\"${ACTIVEMQ_BASE}\" \ -Dactivemq.conf=\"${ACTIVEMQ_CONF}\" \ -Dactivemq.data=\"${ACTIVEMQ_DATA}\" \ $ACTIVEMQ_CYGWIN \ -jar \"${ACTIVEMQ_HOME}/bin/activemq.jar\" $COMMANDLINE_ARGS" $DOIT_POSTFIX RET="$?" fi return $RET } # Check if ActiveMQ is running # # @RET : 0 => the activemq process is running # 1 => process id in $ACTIVEMQ_PIDFILE does not exist anymore # 2 => something is wrong with the pid file # # Note: This function uses globally defined variables # - $ACTIVEMQ_PIDFILE : the name of the pid file checkRunning(){ if [ -f "$ACTIVEMQ_PIDFILE" ]; then if [ -z "`cat $ACTIVEMQ_PIDFILE`" ];then echo "ERROR: Pidfile '$ACTIVEMQ_PIDFILE' exists but contains no pid" return 2 fi PID=`cat $ACTIVEMQ_PIDFILE` RET=`ps -p $PID|grep java` if [ -n "$RET" ];then return 0; else return 1; fi else return 1; fi } checkStopRunning(){ PID=$ACTIVEMQ_DATA/stop.pid if [ -f "$PID" ]; then if [ -z "`cat $PID`" ];then echo "ERROR: Pidfile '$PID' exists but contains no pid" return 2 fi THEPID=`cat $PID` RET=`ps -p $THEPID|grep java` if [ -n "$RET" ];then return 0; else return 1; fi else return 1; fi } # Check if ActiveMQ is running # # @RET : 0 => the activemq process is running # 1 => the activemq process is not running # # Note: This function uses globally defined variables # - $ACTIVEMQ_PIDFILE : the name of the pid file invoke_status(){ if ( checkRunning );then PID=`cat $ACTIVEMQ_PIDFILE` echo "ActiveMQ is running (pid '$PID')" exit 0 fi echo "ActiveMQ not running" exit 1 } # Start ActiveMQ if not already running # # @RET : 0 => is now started, is already started # !0 => something went wrong # # Note: This function uses globally defined variables # - $ACTIVEMQ_PIDFILE : the name of the pid file # - $ACTIVEMQ_OPTS : Additional options # - $ACTIVEMQ_SUNJMX_START : options for JMX settings # - $ACTIVEMQ_SSL_OPTS : options for SSL encryption invoke_start(){ if ( checkRunning );then PID=`cat $ACTIVEMQ_PIDFILE` echo "INFO: Process with pid '$PID' is already running" exit 0 fi ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SUNJMX_START $ACTIVEMQ_SSL_OPTS -Djava.awt.headless=true -Djava.io.tmpdir=\"${ACTIVEMQ_TMP}\"" echo "INFO: Starting - inspect logfiles specified in logging.properties and log4j.properties to get details" invokeJar $ACTIVEMQ_PIDFILE exit "$?" } # Start ActiveMQ in foreground (for debugging) # # @RET : 0 => is now started, is already started # !0 => something went wrong # # Note: This function uses globally defined variables # - $ACTIVEMQ_PIDFILE : the name of the pid file # - $ACTIVEMQ_OPTS : Additional options # - $ACTIVEMQ_SUNJMX_START : options for JMX settings # - $ACTIVEMQ_SSL_OPTS : options for SSL encryption invoke_console(){ if ( checkRunning );then echo "ERROR: ActiveMQ is already running" exit 1 fi ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SUNJMX_START $ACTIVEMQ_SSL_OPTS -Djava.awt.headless=true -Djava.io.tmpdir=\"${ACTIVEMQ_TMP}\"" COMMANDLINE_ARGS="start `echo $COMMANDLINE_ARGS|sed 's,^console,,'`" echo "INFO: Starting in foreground, this is just for debugging purposes (stop process by pressing CTRL+C)" invokeJar exit "$?" } # Stop ActiveMQ # # @RET : 0 => stop was successful # !0 => something went wrong # # Note: This function uses globally defined variables # - $ACTIVEMQ_PIDFILE : the name of the pid file # - $ACTIVEMQ_KILL_MAXSECONDS : the number of seconds to wait for termination of broker after sending # shutdown signal by jmx interface invoke_stop(){ RET="1" if ( checkRunning );then ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SSL_OPTS" COMMANDLINE_ARGS="$COMMANDLINE_ARGS $ACTIVEMQ_SUNJMX_CONTROL" invokeJar "stop" RET="$?" PID=`cat $ACTIVEMQ_PIDFILE` echo "INFO: Waiting at least $ACTIVEMQ_KILL_MAXSECONDS seconds for regular process termination of pid '$PID' : " FOUND="0" i=1 while [ $i != $ACTIVEMQ_KILL_MAXSECONDS ]; do if [ ! checkStopRunning ];then if [ ! checkRunning ]; then echo " FINISHED" FOUND="1" fi break fi if (checkRunning);then sleep 1 printf "." else echo " FINISHED" FOUND="1" break fi i=`expr $i + 1` done if [ "$FOUND" -ne "1" ];then echo echo "INFO: Regular shutdown not successful, sending SIGKILL to process with pid '$PID'" kill -KILL $PID RET="1" fi elif [ -f "$ACTIVEMQ_PIDFILE" ];then echo "ERROR: No or outdated process id in '$ACTIVEMQ_PIDFILE'" echo echo "INFO: Removing $ACTIVEMQ_PIDFILE" else echo "ActiveMQ not running" exit 0 fi rm -f $ACTIVEMQ_PIDFILE >/dev/null 2>&1 rm -f $ACTIVEMQ_DATA/stop.pid >/dev/null 2>&1 exit $RET } # Invoke a task on a running ActiveMQ instance # # @RET : 0 => successful # !0 => something went wrong # # Note: This function uses globally defined variables # - $ACTIVEMQ_QUEUEMANAGERURL : The url of the queuemanager # - $ACTIVEMQ_OPTS : Additional options # - $ACTIVEMQ_SUNJMX_START : options for JMX settings # - $ACTIVEMQ_SSL_OPTS : options for SSL encryption invoke_task(){ # call task in java binary if ( checkRunning );then if [ "$1" = "browse" ] && [ -n "$ACTIVEMQ_QUEUEMANAGERURL" ];then ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SSL_OPTS" COMMANDLINE_ARGS="$1 $ACTIVEMQ_QUEUEMANAGERURL `echo $COMMANDLINE_ARGS|sed 's,^browse,,'`" elif [ "$1" = "query" ] && [ -n "$ACTIVEMQ_QUEUEMANAGERURL" ];then ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SSL_OPTS" COMMANDLINE_ARGS="$1 $ACTIVEMQ_SUNJMX_CONTROL `echo $COMMANDLINE_ARGS|sed 's,^query,,'`" else ACTIVEMQ_OPTS="$ACTIVEMQ_OPTS $ACTIVEMQ_SSL_OPTS" COMMANDLINE_ARGS="$COMMANDLINE_ARGS $ACTIVEMQ_SUNJMX_CONTROL" fi invokeJar exit $? else invokeJar exit 1 fi } show_help() { invokeJar RET="$?" cat << EOF Tasks provided by the sysv init script: restart - stop running instance (if there is one), start new instance console - start broker in foreground, useful for debugging purposes status - check if activemq process is running setup - create the specified configuration file for this init script (see next usage section) Configuration of this script: The configuration of this script can be placed on /etc/default/activemq or $HOME/.activemqrc. To use additional configurations for running multiple instances on the same operating system rename or symlink script to a name matching to activemq-instance-<INSTANCENAME>. This changes the configuration location to /etc/default/activemq-instance-<INSTANCENAME> and \$HOME/.activemqrc-instance-<INSTANCENAME>. Configuration files in /etc have higher precedence. EOF exit $RET } # ------------------------------------------------------------------------ # MAIN # show help if [ -z "$1" ];then show_help fi case "$1" in status) invoke_status ;; restart) if ( checkRunning );then $0 stop fi $0 status $0 start $0 status ;; start) invoke_start ;; console) invoke_console ;; stop) invoke_stop ;; *) invoke_task esac
一些参考：
1.init wikipedia https://en.wikipedia.org/wiki/Init
2.（重点）Operating system service management https://en.wikipedia.org/wiki/Operating_system_service_management