[2206] Change getHeader() to return a reference

src/lib/datasrc/memory/zone_table_segment.h

@@ -71,14 +71,10 @@ public:
     virtual ~ZoneTableSegment() {}
 
     /// \brief Return the ZoneTableHeader for the zone table segment.
-    ///
-    /// NOTE: This method should never return \c NULL.
-    virtual ZoneTableHeader* getHeader() = 0;
+    virtual ZoneTableHeader& getHeader() = 0;
 
     /// \brief const version of \c getHeader().
-    ///
-    /// NOTE: This method should never return \c NULL.
-    virtual const ZoneTableHeader* getHeader() const = 0;
+    virtual const ZoneTableHeader& getHeader() const = 0;
 
     /// \brief Return the MemorySegment for the zone table segment.
     virtual isc::util::MemorySegment& getMemorySegment() = 0;

src/lib/datasrc/memory/zone_table_segment_local.cc

@@ -20,14 +20,14 @@ namespace isc {
 namespace datasrc {
 namespace memory {
 
-ZoneTableHeader*
+ZoneTableHeader&
 ZoneTableSegmentLocal::getHeader() {
-     return (&header_);
+     return (header_);
 }
 
-const ZoneTableHeader*
+const ZoneTableHeader&
 ZoneTableSegmentLocal::getHeader() const {
-     return (&header_);
+     return (header_);
 }
 
 MemorySegment&

src/lib/datasrc/memory/zone_table_segment_local.h

@@ -45,14 +45,10 @@ public:
 
     /// \brief Return the ZoneTableHeader for the local zone table
     /// segment implementation.
-    ///
-    /// NOTE: This method will never return \c NULL.
-    virtual ZoneTableHeader* getHeader();
+    virtual ZoneTableHeader& getHeader();
 
     /// \brief const version of \c getHeader().
-    ///
-    /// NOTE: This method will never return \c NULL.
-    virtual const ZoneTableHeader* getHeader() const;
+    virtual const ZoneTableHeader& getHeader() const;
 
     /// \brief Return the MemorySegment for the local zone table segment
     /// implementation (a MemorySegmentLocal instance).

src/lib/datasrc/tests/memory/zone_table_segment_unittest.cc

@@ -55,23 +55,20 @@ TEST_F(ZoneTableSegmentTest, create) {
 }
 
 TEST_F(ZoneTableSegmentTest, getHeader) {
-    // getHeader() should never return NULL.
-    ZoneTableHeader* header = segment_->getHeader();
-    EXPECT_NE(static_cast<void*>(NULL), header);
+    ZoneTableHeader& header = segment_->getHeader();
 
     // The zone table is unset.
-    ZoneTable* table = header->getTable();
+    ZoneTable* table = header.getTable();
     EXPECT_EQ(static_cast<void*>(NULL), table);
 }
 
 TEST_F(ZoneTableSegmentTest, getHeaderConst) {
-    // getHeader() should never return NULL.
-    const ZoneTableHeader* header =
+    // Test const methods
+    const ZoneTableHeader& header =
          static_cast<const ZoneTableSegment*>(segment_)->getHeader();
-    EXPECT_NE(static_cast<void*>(NULL), header);
 
     // The zone table is unset.
-    const ZoneTable* table = header->getTable();
+    const ZoneTable* table = header.getTable();
     EXPECT_EQ(static_cast<void*>(NULL), table);
 }