mysql upstart workaround

The problem?

https://wiki.ubuntu.com/LucidLynx/ReleaseNotes

"""Upstart jobs cannot be run in a chroot:

Upstart jobs cannot be started in a chroot because upstart acts as a
service supervisor, and processes within the chroot are unable to
communicate with the upstart running outside of the chroot (430224).
This will cause some packages that have been converted to use upstart
jobs instead of init scripts to fail to upgrade within a chroot. Users
are advised to configure their chroots with /sbin/initctl pointing to
/bin/true, with the following commands run within the chroot:

dpkg-divert --local --rename --add /sbin/initctl
ln -s /bin/true /sbin/initctl"""

https://bugs.launchpad.net/ubuntu/+source/upstart/+bug/430224

In other words, starting an upstart job inside a chroot actually starts
it outside the chroot. Upstart uses dbus to communicate with processes,
and dbus uses unix sockets in the abstract namespace, which transcends
the filesystem, and thus, chroot.

bin/tklpatch-chroot

@@ -1,6 +1,136 @@
 #!/bin/bash -e
 # Copyright (c) 2009 Alon Swartz <alon@turnkeylinux.org> - all rights reserved
 
+write_dummy_initctl() {
+    root=$1
+
+    cat>$root/sbin/initctl<<'EOF'
+#!/bin/bash
+
+set -e
+set -u
+${DEBIAN_SCRIPT_DEBUG:+ set -v -x}
+
+. /lib/lsb/init-functions
+ERR_LOGGER="logger -p daemon.err -t /etc/init.d/mysql -i"
+MYADMIN="/usr/bin/mysqladmin --defaults-file=/etc/mysql/debian.cnf"
+
+mysqld_get_param() {
+        /usr/sbin/mysqld --print-defaults \
+                | tr " " "\n" \
+                | grep -- "--$1" \
+                | tail -n 1 \
+                | cut -d= -f2
+}
+
+mysqld_status () {
+    ping_output=`$MYADMIN ping 2>&1`; ping_alive=$(( ! $? ))
+
+    ps_alive=0
+    pidfile=`mysqld_get_param pid-file`
+    if [ -f "$pidfile" ] && ps `cat $pidfile` >/dev/null 2>&1; then ps_alive=1; fi
+
+    if [ "$1" = "check_alive"  -a  $ping_alive = 1 ] ||
+       [ "$1" = "check_dead"   -a  $ping_alive = 0  -a  $ps_alive = 0 ]; then
+        return 0 # EXIT_SUCCESS
+    else
+        if [ "$2" = "warn" ]; then
+            echo -e "$ps_alive processes alive and '$MYADMIN ping' resulted in\n$ping_output\n" | $ERR_LOGGER -p daemon.debug
+        fi
+        return 1 # EXIT_FAILURE
+    fi
+}
+
+start_mysql()
+{
+    test -x /usr/sbin/mysqld || exit 0
+
+    log_daemon_msg "Starting MySQL database server" "mysqld"
+    if mysqld_status check_alive nowarn; then
+       log_progress_msg "already running"
+       log_end_msg 0
+    else
+        /usr/bin/mysqld_safe > /dev/null 2>&1 &
+        # 6s was reported in #352070 to be too few when using ndbcluster
+        for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14; do
+            sleep 1
+            if mysqld_status check_alive nowarn ; then break; fi
+            log_progress_msg "."
+        done
+        if mysqld_status check_alive warn; then
+            log_end_msg 0
+            # Now start mysqlcheck or whatever the admin wants.
+            output=$(/etc/mysql/debian-start)
+            [ -n "$output" ] && log_action_msg "$output"
+        else
+            log_end_msg 1
+            log_failure_msg "Please take a look at the syslog"
+        fi
+    fi
+}
+
+stop_mysql()
+{
+        # * As a passwordless mysqladmin (e.g. via ~/.my.cnf) must be possible
+        # at least for cron, we can rely on it here, too. (although we have
+        # to specify it explicit as e.g. sudo environments points to the normal
+        # users home and not /root)
+        log_daemon_msg "Stopping MySQL database server" "mysqld"
+        if ! mysqld_status check_dead nowarn; then
+          set +e
+          shutdown_out=`$MYADMIN shutdown 2>&1`; r=$?
+          set -e
+          if [ "$r" -ne 0 ]; then
+            log_end_msg 1
+            [ "$VERBOSE" != "no" ] && log_failure_msg "Error: $shutdown_out"
+            log_daemon_msg "Killing MySQL database server by signal" "mysqld"
+            killall -15 mysqld
+            server_down=
+            for i in 1 2 3 4 5 6 7 8 9 10; do
+              sleep 1
+              if mysqld_status check_dead nowarn; then server_down=1; break; fi
+            done
+          if test -z "$server_down"; then killall -9 mysqld; fi
+          fi
+        fi
+}
+
+start()
+{
+    if [ "$1" == "mysql" ]; then
+        start_mysql
+    fi
+
+}
+
+stop()
+{
+    if [ "$1" == "mysql" ]; then
+        stop_mysql
+    fi
+}
+
+op=$(basename $0)
+service=$1
+
+case "$op" in
+    start)
+        start $1
+        ;;
+
+    stop)
+        stop $1
+        ;;
+
+    *)
+        ;;
+esac
+
+exit
+EOF
+    chmod +x $root/sbin/initctl
+}
+
 fatal() {
     echo "fatal: $@" 1>&2
     exit 1
@@ -39,11 +169,18 @@ command=$@
 
 
 if [ ! "$root" == "/" ]; then
+    if ! [ -f $root/sbin/initctl.distrib ]; then
+        chroot $root dpkg-divert --local --rename --add /sbin/initctl 
+        write_dummy_initctl $root
+        traphook="rm $root/sbin/initctl; chroot $root dpkg-divert --local --rename --remove /sbin/initctl;"
+    fi
+
     resolvconf=$root/etc/resolv.conf
     if ! [ -f $root/etc/debian_chroot ]; then
         echo tklpatch > $root/etc/debian_chroot
-        traphook="rm -f /etc/debian_chroot;"
+        traphook="${traphook}rm -f /etc/debian_chroot;"
     fi
+
     if ! [ -f $resolvconf.bak ]; then
         mv $resolvconf $resolvconf.bak
         cp /etc/resolv.conf $resolvconf