Use mysqladmin for checking the socket

This should avoid the long delay and service start failure in case the socket exists, some process is hanging on it, but no replies are sent, like when simulating the server using nc

mariadb.spec

@@ -146,7 +146,7 @@
 
 Name:             mariadb
 Version:          %{compatver}.%{bugfixver}
-Release:          1%{?with_debug:.debug}%{?dist}
+Release:          2%{?with_debug:.debug}%{?dist}
 Epoch:            3
 
 Summary:          A community developed branch of MySQL
@@ -1575,6 +1575,9 @@ fi
 %endif
 
 %changelog
+* Tue Jun 05 2018 Honza Horak <hhorak@redhat.com> - 3:10.2.15-2
+- Use mysqladmin for checking the socket
+
 * Wed May 23 2018 Michal Schorm <mschorm@redhat.com> - 3:10.2.15-1
 - Rebase to 10.2.15
 - CVEs fixed: #1568962

mysql-check-socket.sh

@@ -25,10 +25,10 @@ if test -e "$socketfile" ; then
     fi
 
     # some process uses the socket file
-    if fuser "$socketfile" &>/dev/null ; then
-        socketpid=$(fuser "$socketfile" 2>/dev/null)
+    response=`@bindir@/mysqladmin --no-defaults --socket="$socketfile" --user=UNKNOWN_MYSQL_USER --connect-timeout="${CHECKSOCKETTIMEOUT:-10}" ping 2>&1`
+    if [ $? -qe 0 ] || echo "$response" | grep -q "Access denied for user" ; then
         echo "Is another MySQL daemon already running with the same unix socket?" >&2
-        echo "Please, stop the process $socketpid or remove $socketfile manually to start the service." >&2
+        echo "Please, stop the process using the socket $socketfile or remove the file manually to start the service." >&2
         exit 1
     fi