Add flag for Excel 4 macros in composite documents

poi/src/main/java/org/apache/poi/hssf/record/BoundSheetRecord.java

@@ -39,6 +39,7 @@ public final class BoundSheetRecord extends StandardRecord {
     public static final short sid = 0x0085;
     private static final BitField hiddenFlag = BitFieldFactory.getInstance(0x01);
     private static final BitField veryHiddenFlag = BitFieldFactory.getInstance(0x02);
+    private static final BitField xl4Flag = BitFieldFactory.getInstance(0x100);
 
     private int field_1_position_of_BOF;
     private int field_2_option_flags;
@@ -186,6 +187,24 @@ public final class BoundSheetRecord extends StandardRecord {
         field_2_option_flags = veryHiddenFlag.setBoolean(field_2_option_flags, veryHidden);
     }
 
+    /**
+     * Is the sheet an Excel 4 macro sheet?
+     *
+     * @return {@code true} if very hidden
+     */
+    public boolean isExcel4Macro() {
+        return xl4Flag.isSet(field_2_option_flags);
+    }
+
+    /**
+     * Is the sheet an Excel 4 macro sheet?
+     *
+     * @param xl4flag {@code true} if an excel 4 macro sheet
+     */
+    public void setExcel4Macro(boolean xl4flag) {
+        field_2_option_flags = xl4Flag.setBoolean(field_2_option_flags, xl4flag);
+    }
+
     /**
      * Converts a List of {@link BoundSheetRecord}s to an array and sorts by the position of their
      * BOFs.

poi/src/test/java/org/apache/poi/hssf/eventusermodel/TestHSSFEventFactory.java

@@ -166,4 +166,26 @@ final class TestHSSFEventFactory {
             Biff8EncryptionKey.setCurrentUserPassword(null);
         }
     }
+
+    @Test
+    void testXL4Workbook() throws Exception {
+        // This document has a single Excel 4 macro in it
+        openSample("66503.xls");
+        assertEquals(records.stream()
+                .filter(r -> r instanceof BoundSheetRecord)
+                .map(r -> (BoundSheetRecord)r)
+                .filter(BoundSheetRecord::isExcel4Macro)
+                .count(), 1);
+    }
+
+    @Test
+    void testXL4Workbook_false() throws Exception {
+        // This document does not have an Excel 4 macro in it
+        openSample("42844.xls");
+        assertEquals(records.stream()
+                .filter(r -> r instanceof BoundSheetRecord)
+                .map(r -> (BoundSheetRecord)r)
+                .filter(BoundSheetRecord::isExcel4Macro)
+                .count(), 0);
+    }
 }