Support --defaults-group-suffix option in systemd unit file

Related: #1400702

community-mysql.spec

@@ -962,6 +962,8 @@ fi
 %changelog
 * Mon Aug 28 2017 Honza Horak <hhorak@redhat.com> - 5.7.19-6
 - Add bundled(boost) virtual provide
+- Support --defaults-group-suffix option in systemd unit file
+  Related: #1400702
 
 * Fri Aug 04 2017 Honza Horak <hhorak@redhat.com> - 5.7.19-5
 - Allow to use MD5 in FIPS mode

mysql-scripts-common.sh

@@ -18,13 +18,23 @@ get_mysql_option(){
 	sections="$1"
 	option_name="$2"
 	default_value="$3"
-	result=`@bindir@/my_print_defaults $sections | sed -n "s/^--${option_name}=//p" | tail -n 1`
+	result=`@bindir@/my_print_defaults $my_print_defaults_extra_args $sections | sed -n "s/^--${option_name}=//p" | tail -n 1`
 	if [ -z "$result" ]; then
 	    # not found, use default
 	    result="${default_value}"
 	fi
 }
 
+# For the case of running more instances via systemd, scrits that source
+# this file can get --default-group-suffix or similar option as the first
+# argument. The utility my_print_defaults needs to use it as well, so the
+# scripts sourcing this file work with the same options as the daemon.
+my_print_defaults_extra_args=''
+while echo "$1" | grep -q '^--defaults' ; do
+	my_print_defaults_extra_args="${my_print_defaults_extra_args} $1"
+	shift
+done
+
 # Defaults here had better match what mysqld_safe will default to
 # The option values are generally defined on three important places
 # on the default installation:

mysql@.service.in

@@ -34,15 +34,14 @@ After=network.target
 Type=forking
 User=mysql
 Group=mysql
-PIDFile=@PID_FILE_DIR@/@DAEMON_NO_PREFIX@.pid
 
-ExecStartPre=@libexecdir@/mysql-check-socket
-ExecStartPre=@libexecdir@/mysql-prepare-db-dir %n
+ExecStartPre=@libexecdir@/mysql-check-socket --defaults-group-suffix=.%I
+ExecStartPre=@libexecdir@/mysql-prepare-db-dir --defaults-group-suffix=.%I %n
 # Note: we set --basedir to prevent probes that might trigger SELinux alarms,
 # per bug #547485
 ExecStart=@libexecdir@/mysqld --defaults-group-suffix=.%I --daemonize --basedir=@prefix@ --pid-file=@PID_FILE_DIR@/@DAEMON_NO_PREFIX@.pid
-ExecStartPost=@libexecdir@/mysql-check-upgrade
-ExecStopPost=@libexecdir@/mysql-wait-stop
+ExecStartPost=@libexecdir@/mysql-check-upgrade --defaults-group-suffix=.%I
+ExecStopPost=@libexecdir@/mysql-wait-stop --defaults-group-suffix=.%I
 
 # Give a reasonable amount of time for the server to start up/shut down
 TimeoutSec=300