common-ha: fixes for Debian-based systems

1) Debian-based systems don't have /usr/libexec/... and there is
a hard-coded invocation of /usr/libexec/ganesha/ganesha-ha.sh within
ganesha-ha.sh itself.
Fix: save $0 and use it instead for further invocations of self.

2) default shell is /bin/dash (not /bin/bash). Various runner_run()
invocations for ganesha used what amounts to
  exec("sh /usr/$libexec/ganesha/ganesha-ha.sh ...);
which executes the script using the default shell, but there are
some bash-specific idioms that don't work if the shell is dash.
Fix: change to exec("/usr/$libexec/ganesha/ganesha-ha.sh ...); so that
the shebang forces the use of /bin/bash

3) Fedora and RHEL7 have merged /bin/ and /usr/bin, /bin is a symlink
to /usr/bin. Debian-based systems are not merged, and systemd systems
have /bin/systemctl. The logic to find .../bin/systemctl is backwards.
If the logic looks for /usr/bin/systemctl it will not find it on
Debian-based systems; if it looks for /bin/systemctl it will find it
on Fedora and RHEL by virtue of the symlink. (RHEL6 and others will
find their respective init regardless.)
Fix: change the logic to look for /bin/systemctl instead.

4) The logic for deciding to run systemctl (or not) is a bit silly.
Fix: simply invoke the found method via the function pointer in the
table.

Change-Id: I33681b296a73aebb078bda6ac0d3a1d3b9770a21
BUG: 1440148
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: https://review.gluster.org/17013
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: jiffin tony Thottan <jthottan@redhat.com>

1 files changed, 11 insertions, 10 deletions

diff --git a/extras/ganesha/scripts/ganesha-ha.sh b/extras/ganesha/scripts/ganesha-ha.sh
index f8eb776a1a8..b62fb306cc9 100644
--- a/extras/ganesha/scripts/ganesha-ha.sh
+++ b/extras/ganesha/scripts/ganesha-ha.sh
@@ -20,6 +20,7 @@
 # ensure that the NFS GRACE DBUS signal is sent after the VIP moves to
 # the new host.
 
+GANESHA_HA_SH=$(realpath $0)
 HA_NUM_SERVERS=0
 HA_SERVERS=""
 HA_VOL_NAME="gluster_shared_storage"
@@ -68,9 +69,9 @@ function find_rhel7_conf
          done
 }
 
-if [ -z $CONFFILE ]
+if [ -z ${CONFFILE} ]
         then
-        find_rhel7_conf $OPTIONS
+        find_rhel7_conf ${OPTIONS}
 
 fi
 
@@ -90,9 +91,9 @@ usage() {
 
 determine_service_manager () {
 
-        if [ -e "/usr/bin/systemctl" ];
+        if [ -e "/bin/systemctl" ];
         then
-                SERVICE_MAN="/usr/bin/systemctl"
+                SERVICE_MAN="/bin/systemctl"
         elif [ -e "/sbin/invoke-rc.d" ];
         then
                 SERVICE_MAN="/sbin/invoke-rc.d"
@@ -100,7 +101,7 @@ determine_service_manager () {
         then
                 SERVICE_MAN="/sbin/service"
         fi
-        if [ "$SERVICE_MAN" == "DISTRO_NOT_FOUND" ]
+        if [ "${SERVICE_MAN}" == "DISTRO_NOT_FOUND" ]
         then
                 echo "Service manager not recognized, exiting"
                 exit 1
@@ -113,21 +114,21 @@ manage_service ()
         local new_node=${2}
         local option=
 
-        if [ "$action" == "start" ]; then
+        if [ "${action}" == "start" ]; then
                 option="yes"
         else
                 option="no"
         fi
         ssh -oPasswordAuthentication=no -oStrictHostKeyChecking=no -i \
-${SECRET_PEM} root@${new_node} "/usr/libexec/ganesha/ganesha-ha.sh --setup-ganesha-conf-files $HA_CONFDIR $option"
+${SECRET_PEM} root@${new_node} "${GANESHA_HA_SH} --setup-ganesha-conf-files $HA_CONFDIR $option"
 
-        if [ "$SERVICE_MAN" == "/usr/bin/systemctl" ]
+        if [ "${SERVICE_MAN}" == "/bin/systemctl" ]
         then
                 ssh -oPasswordAuthentication=no -oStrictHostKeyChecking=no -i \
-${SECRET_PEM} root@${new_node} "$SERVICE_MAN  ${action} nfs-ganesha"
+${SECRET_PEM} root@${new_node} "${SERVICE_MAN}  ${action} nfs-ganesha"
         else
                 ssh -oPasswordAuthentication=no -oStrictHostKeyChecking=no -i \
-${SECRET_PEM} root@${new_node} "$SERVICE_MAN nfs-ganesha ${action}"
+${SECRET_PEM} root@${new_node} "${SERVICE_MAN} nfs-ganesha ${action}"
         fi
 }