--- /dev/null
+Title: Debian init.d boot script example for rsyslog
+Tags: english, debian
+Date: 2013-11-02 22:40
+
+<p>If one of the points of switching to a new init system in Debian is
+<a href="http://thomas.goirand.fr/blog/?p=147">to get rid of huge
+init.d scripts</a>, I doubt we need to switch away from sysvinit and
+init.d scripts at all. Here is an example init.d script, ie a rewrite
+of /etc/init.d/rsyslog:</p>
+
+<p><pre>
+#!/lib/init/init-d-script
+### BEGIN INIT INFO
+# Provides: rsyslog
+# Required-Start: $remote_fs $time
+# Required-Stop: umountnfs $time
+# X-Stop-After: sendsigs
+# Default-Start: 2 3 4 5
+# Default-Stop: 0 1 6
+# Short-Description: enhanced syslogd
+# Description: Rsyslog is an enhanced multi-threaded syslogd.
+# It is quite compatible to stock sysklogd and can be
+# used as a drop-in replacement.
+### END INIT INFO
+DESC="enhanced syslogd"
+DAEMON=/usr/sbin/rsyslogd
+</pre></p>
+
+<p>Pretty minimalistic to me... For the record, the original sysv-rc
+script was 126 lines, and the above is just 15 lines, most of the meta
+info/comments.</p>
+
+<p>How to do this, you ask? Well, one create a new script
+/lib/init/init-d-script looking something like this:
+
+<p><pre>
+#!/bin/sh
+
+# Define LSB log_* functions.
+# Depend on lsb-base (>= 3.2-14) to ensure that this file is present
+# and status_of_proc is working.
+. /lib/lsb/init-functions
+
+#
+# Function that starts the daemon/service
+
+#
+do_start()
+{
+ # Return
+ # 0 if daemon has been started
+ # 1 if daemon was already running
+ # 2 if daemon could not be started
+ start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
+ || return 1
+ start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
+ $DAEMON_ARGS \
+ || return 2
+ # Add code here, if necessary, that waits for the process to be ready
+ # to handle requests from services started subsequently which depend
+ # on this one. As a last resort, sleep for some time.
+}
+
+#
+# Function that stops the daemon/service
+#
+do_stop()
+{
+ # Return
+ # 0 if daemon has been stopped
+ # 1 if daemon was already stopped
+ # 2 if daemon could not be stopped
+ # other if a failure occurred
+ start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
+ RETVAL="$?"
+ [ "$RETVAL" = 2 ] && return 2
+ # Wait for children to finish too if this is a daemon that forks
+ # and if the daemon is only ever run from this initscript.
+ # If the above conditions are not satisfied then add some other code
+ # that waits for the process to drop all resources that could be
+ # needed by services started subsequently. A last resort is to
+ # sleep for some time.
+ start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
+ [ "$?" = 2 ] && return 2
+ # Many daemons don't delete their pidfiles when they exit.
+ rm -f $PIDFILE
+ return "$RETVAL"
+}
+
+#
+# Function that sends a SIGHUP to the daemon/service
+#
+do_reload() {
+ #
+ # If the daemon can reload its configuration without
+ # restarting (for example, when it is sent a SIGHUP),
+ # then implement that here.
+ #
+ start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME
+ return 0
+}
+
+SCRIPTNAME=$1
+scriptbasename="$(basename $1)"
+echo "SN: $scriptbasename"
+if [ "$scriptbasename" != "init-d-library" ] ; then
+ script="$1"
+ shift
+ . $script
+else
+ exit 0
+fi
+
+NAME=$(basename $DAEMON)
+PIDFILE=/var/run/$NAME.pid
+
+# Exit if the package is not installed
+#[ -x "$DAEMON" ] || exit 0
+
+# Read configuration variable file if it is present
+[ -r /etc/default/$NAME ] && . /etc/default/$NAME
+
+# Load the VERBOSE setting and other rcS variables
+. /lib/init/vars.sh
+
+case "$1" in
+ start)
+ [ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
+ do_start
+ case "$?" in
+ 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
+ 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
+ esac
+ ;;
+ stop)
+ [ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
+ do_stop
+ case "$?" in
+ 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
+ 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
+ esac
+ ;;
+ status)
+ status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
+ ;;
+ #reload|force-reload)
+ #
+ # If do_reload() is not implemented then leave this commented out
+ # and leave 'force-reload' as an alias for 'restart'.
+ #
+ #log_daemon_msg "Reloading $DESC" "$NAME"
+ #do_reload
+ #log_end_msg $?
+ #;;
+ restart|force-reload)
+ #
+ # If the "reload" option is implemented then remove the
+ # 'force-reload' alias
+ #
+ log_daemon_msg "Restarting $DESC" "$NAME"
+ do_stop
+ case "$?" in
+ 0|1)
+ do_start
+ case "$?" in
+ 0) log_end_msg 0 ;;
+ 1) log_end_msg 1 ;; # Old process is still running
+ *) log_end_msg 1 ;; # Failed to start
+ esac
+ ;;
+ *)
+ # Failed to stop
+ log_end_msg 1
+ ;;
+ esac
+ ;;
+ *)
+ echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
+ exit 3
+ ;;
+esac
+
+:
+</pre></p>
+
+<p>It is based on /etc/init.d/skeleton, and could be improved quite a
+lot. I did not try hard to optimize it nor make it more robust.</p>
+
+<p>A better argument for switching init system in Debian than reducing
+the size of init scripts (which is a good thing to do anyway), is to
+get boot system that is able to handle the kernel events sensibly and
+robustly, and do not depend the boot to run sequentially. The boot
+and the kernel have not behaved sequentially in year.</p>
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