Fix check for -Xlog in cassandra-env.sh

 patch by Yakir Gibraltar; reviewed by Adam Holmberg, Mick Semb Wever for CASSANDRA-16279

CHANGES.txt

@@ -1,4 +1,5 @@
 4.0-beta5
+ * Fix check for -Xlog in cassandra-env.sh (CASSANDRA-16279)
  * SSLFactory should initialize SSLContext before setting protocols (CASSANDRA-16362)
  * Restore sasi dependencies jflex, snowball-stemmer, and concurrent-trees, in the cassandra-all pom (CASSANDRA-16303)
  * Fix DecimalDeserializer#toString OOM (CASSANDRA-14925)

conf/cassandra-env.sh

@@ -95,15 +95,15 @@ fi
 if [ $JAVA_VERSION -ge 11 ] ; then
     # See description of https://bugs.openjdk.java.net/browse/JDK-8046148 for details about the syntax
     # The following is the equivalent to -XX:+PrintGCDetails -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=10M
-    echo "$JVM_OPTS" | grep -q "^-[X]log:gc"
+    echo "$JVM_OPTS" | grep -qe "-[X]log:gc"
     if [ "$?" = "1" ] ; then # [X] to prevent ccm from replacing this line
         # only add -Xlog:gc if it's not mentioned in jvm-server.options file
         mkdir -p ${CASSANDRA_LOG_DIR}
         JVM_OPTS="$JVM_OPTS -Xlog:gc=info,heap*=trace,age*=debug,safepoint=info,promotion*=trace:file=${CASSANDRA_LOG_DIR}/gc.log:time,uptime,pid,tid,level:filecount=10,filesize=10485760"
     fi
 else
     # Java 8
-    echo "$JVM_OPTS" | grep -q "^-[X]loggc"
+    echo "$JVM_OPTS" | grep -qe "-[X]loggc"
     if [ "$?" = "1" ] ; then # [X] to prevent ccm from replacing this line
         # only add -Xlog:gc if it's not mentioned in jvm-server.options file
         mkdir -p ${CASSANDRA_LOG_DIR}