Check that the previous date was a number

src/freedombone

@@ -4776,24 +4776,27 @@ function time_synchronisation {
   echo 'DATE_BEFORE=$(date)' >> /usr/bin/updatedate
   echo 'BEFORE=$(date "+%s")' >> /usr/bin/updatedate
   echo 'BACKWARDS_BETWEEN=0' >> /usr/bin/updatedate
+  echo 're="^[0-9]+$"' >> /usr/bin/updatedate
   echo '# If the date was previously set' >> /usr/bin/updatedate
   echo 'if [ -s "$BEFORE_DATE_FILE" ]; then' >> /usr/bin/updatedate
   echo '    filesize=$(wc -c "$BEFORE_DATE_FILE" | cut -f 1 -d " ")' >> /usr/bin/updatedate
   echo '    if [ $filesize -ge 5 ]; then' >> /usr/bin/updatedate
   echo '        BEFORE_FILE=$(cat $BEFORE_DATE_FILE)' >> /usr/bin/updatedate
-  echo '        BEFORE_FULLDATE=$(cat $BEFORE_FULLDATE_FILE)' >> /usr/bin/updatedate
-  echo '        # is the date going backwards?' >> /usr/bin/updatedate
-  echo '        if (( $BEFORE_FILE > $BEFORE )); then' >> /usr/bin/updatedate
-  echo '            echo -n "Date went backwards between tlsdate updates. " >> $LOGFILE' >> /usr/bin/updatedate
-  echo '            echo -n "$BEFORE_FILE > $BEFORE, " >> $LOGFILE' >> /usr/bin/updatedate
-  echo '            echo "$BEFORE_FULLDATE > $DATE_BEFORE" >> $LOGFILE' >> /usr/bin/updatedate
-  echo '            # Send a warning email' >> /usr/bin/updatedate
-  echo '            echo $(tail $LOGFILE -n 2) | mail -s "tlsdate anomaly" $EMAIL' >> /usr/bin/updatedate
-  echo '            # Try another time source' >> /usr/bin/updatedate
-  echo '            TIMESOURCE=$TIMESOURCE2' >> /usr/bin/updatedate
-  echo '            # try running without any parameters' >> /usr/bin/updatedate
-  echo '            tlsdate >> $LOGFILE' >> /usr/bin/updatedate
-  echo '            BACKWARDS_BETWEEN=1' >> /usr/bin/updatedate
+  echo '        if [[ $BEFORE_FILE =~ $re ]] ; then' >> /usr/bin/updatedate
+  echo '            BEFORE_FULLDATE=$(cat $BEFORE_FULLDATE_FILE)' >> /usr/bin/updatedate
+  echo '            # is the date going backwards?' >> /usr/bin/updatedate
+  echo '            if (( $BEFORE_FILE > $BEFORE )); then' >> /usr/bin/updatedate
+  echo '                echo -n "Date went backwards between tlsdate updates. " >> $LOGFILE' >> /usr/bin/updatedate
+  echo '                echo -n "$BEFORE_FILE > $BEFORE, " >> $LOGFILE' >> /usr/bin/updatedate
+  echo '                echo "$BEFORE_FULLDATE > $DATE_BEFORE" >> $LOGFILE' >> /usr/bin/updatedate
+  echo '                # Send a warning email' >> /usr/bin/updatedate
+  echo '                echo $(tail $LOGFILE -n 2) | mail -s "tlsdate anomaly" $EMAIL' >> /usr/bin/updatedate
+  echo '                # Try another time source' >> /usr/bin/updatedate
+  echo '                TIMESOURCE=$TIMESOURCE2' >> /usr/bin/updatedate
+  echo '                # try running without any parameters' >> /usr/bin/updatedate
+  echo '                tlsdate >> $LOGFILE' >> /usr/bin/updatedate
+  echo '                BACKWARDS_BETWEEN=1' >> /usr/bin/updatedate
+  echo '            fi' >> /usr/bin/updatedate
   echo '        fi' >> /usr/bin/updatedate
   echo '    fi' >> /usr/bin/updatedate
   echo 'fi' >> /usr/bin/updatedate