Revert back private members of irt_repeat

Author: dyemanov

src/jrd/btr.cpp

@@ -924,8 +924,9 @@ bool BTR_delete_index(thread_db* tdbb, WIN* window, USHORT id)
 	{
 		index_root_page::irt_repeat* irt_desc = root->irt_rpt + id;
 		CCH_MARK(tdbb, window);
-		const PageNumber next(window->win_page.getPageSpaceID(), irt_desc->irt_root);
-		tree_exists = !irt_desc->isEmpty();
+		const ULONG rootPage = irt_desc->getRoot();
+		const PageNumber next(window->win_page.getPageSpaceID(), rootPage);
+		tree_exists = (rootPage != 0);
 
 		// remove the pointer to the top-level index page before we delete it
 		irt_desc->setEmpty();
@@ -961,11 +962,12 @@ bool BTR_description(thread_db* tdbb, jrd_rel* relation, index_root_page* root,
 
 	const index_root_page::irt_repeat* irt_desc = &root->irt_rpt[id];
 
-	if (irt_desc->isEmpty())
+	const ULONG rootPage = irt_desc->getRoot();
+	if (!rootPage)
 		return false;
 
 	idx->idx_id = id;
-	idx->idx_root = irt_desc->irt_root;
+	idx->idx_root = rootPage;
 	idx->idx_count = irt_desc->irt_keys;
 	idx->idx_flags = irt_desc->irt_flags;
 	idx->idx_runtime_flags = 0;
@@ -1450,7 +1452,7 @@ void BTR_insert(thread_db* tdbb, WIN* root_window, index_insertion* insertion)
 	// update the index root page.  Oh boy.
 	index_root_page* root = (index_root_page*) CCH_FETCH(tdbb, root_window, LCK_write, pag_root);
 
-	window.win_page = root->irt_rpt[idx->idx_id].irt_root;
+	window.win_page = root->irt_rpt[idx->idx_id].getRoot();
 	bucket = (btree_page*) CCH_FETCH(tdbb, &window, LCK_write, pag_index);
 
 	if (window.win_page.getPageNum() != idx->idx_root)
@@ -1500,7 +1502,7 @@ void BTR_insert(thread_db* tdbb, WIN* root_window, index_insertion* insertion)
 			BUGCHECK(204);	// msg 204 index inconsistent
 		}
 
-		window.win_page = root->irt_rpt[idx->idx_id].irt_root;
+		window.win_page = root->irt_rpt[idx->idx_id].getRoot();
 		bucket = (btree_page*) CCH_FETCH(tdbb, &window, LCK_write, pag_index);
 		key.key_length = ret_key.key_length;
 		memcpy(key.key_data, ret_key.key_data, ret_key.key_length);
@@ -2392,15 +2394,13 @@ void BTR_selectivity(thread_db* tdbb, jrd_rel* relation, USHORT id, SelectivityL
 	if (!root)
 		return;
 
-	if (id >= root->irt_count || root->irt_rpt[id].isEmpty())
+	if (id >= root->irt_count || !root->irt_rpt[id].getRoot())
 	{
 		CCH_RELEASE(tdbb, &window);
 		return;
 	}
 
-	ULONG page = root->irt_rpt[id].irt_root;
-	fb_assert(page);
-
+	ULONG page = root->irt_rpt[id].getRoot();
 	const bool descending = (root->irt_rpt[id].irt_flags & irt_descending);
 	const ULONG segments = root->irt_rpt[id].irt_keys;
 
@@ -3335,7 +3335,7 @@ static USHORT compress_root(thread_db* tdbb, index_root_page* page)
 	for (const index_root_page::irt_repeat* const end = root_idx + page->irt_count;
 		 root_idx < end; root_idx++)
 	{
-		if (!root_idx->isEmpty())
+		if (root_idx->getRoot())
 		{
 			const USHORT len = root_idx->irt_keys * sizeof(irtd);
 			p -= len;

src/jrd/ods.h

@@ -368,24 +368,26 @@ struct index_root_page
 	USHORT irt_count;				// Number of indices
 	struct irt_repeat
 	{
+		friend class index_root_page;	// to allow offset check for private members
+	private:
 		union
 		{
 			FB_UINT64 irt_transaction;	// transaction in progress
 			ULONG irt_root;				// page number of index root
 		};
+	public:
 		USHORT irt_desc;				// offset to key descriptions
 		USHORT irt_flags;				// index flags
 		UCHAR irt_keys;					// number of keys in index
 
 		TraNumber inProgress() const;
-		bool isEmpty() const;
-		bool isUsed() const;
-
-		void setEmpty();
 		void setInProgress(TraNumber traNumber);
-		void clearInProgress(ULONG rootPage);
+
+		ULONG getRoot() const;
 		void setRoot(ULONG rootPage);
 
+		bool isUsed() const;
+		void setEmpty();
 	} irt_rpt[1];
 
 	static_assert(sizeof(struct irt_repeat) == 16, "struct irt_repeat size mismatch");
@@ -425,16 +427,6 @@ inline constexpr USHORT irt_primary			= 16;
 inline constexpr USHORT irt_expression		= 32;
 inline constexpr USHORT irt_condition		= 64;
 
-inline TraNumber index_root_page::irt_repeat::inProgress() const
-{
-	return (irt_flags & irt_in_progress) ? irt_transaction : 0;
-}
-
-inline bool index_root_page::irt_repeat::isEmpty() const
-{
-	return (irt_flags & irt_in_progress) || (irt_root == 0);
-}
-
 inline bool index_root_page::irt_repeat::isUsed() const
 {
 	return (irt_flags & irt_in_progress) || (irt_root != 0);
@@ -443,15 +435,26 @@ inline bool index_root_page::irt_repeat::isUsed() const
 inline void index_root_page::irt_repeat::setEmpty()
 {
 	irt_transaction = 0;
+	fb_assert(irt_root == 0);
 	irt_flags = 0;
 }
 
+inline TraNumber index_root_page::irt_repeat::inProgress() const
+{
+	return (irt_flags & irt_in_progress) ? irt_transaction : 0;
+}
+
 inline void index_root_page::irt_repeat::setInProgress(TraNumber traNumber)
 {
 	irt_transaction = traNumber;
 	irt_flags |= irt_in_progress;
 }
 
+inline ULONG index_root_page::irt_repeat::getRoot() const
+{
+	return (irt_flags & irt_in_progress) ? 0 : irt_root;
+}
+
 inline void index_root_page::irt_repeat::setRoot(ULONG rootPage)
 {
 	irt_root = rootPage;

src/jrd/validation.cpp

@@ -1976,12 +1976,10 @@ Validation::RTN Validation::walk_index(jrd_rel* relation, index_root_page* root_
  **************************************/
 	Database* dbb = vdr_tdbb->getDatabase();
 
-	if (root_page->irt_rpt[id].isEmpty())
+	const ULONG page_number = root_page->irt_rpt[id].getRoot();
+	if (!page_number)
 		return rtn_ok;
 
-	const ULONG page_number = root_page->irt_rpt[id].irt_root;
-	fb_assert(page_number);
-
 	const bool unique = (root_page->irt_rpt[id].irt_flags & (irt_unique | idx_primary));
 	const bool descending = (root_page->irt_rpt[id].irt_flags & irt_descending);
 	const bool condition = (root_page->irt_rpt[id].irt_flags & irt_condition);
@@ -3211,13 +3209,13 @@ Validation::RTN Validation::walk_root(jrd_rel* relation, bool getInfo)
 	if (!relPages->rel_index_root)
 		return corrupt(VAL_INDEX_ROOT_MISSING, relation);
 
-	index_root_page* page = 0;
+	index_root_page* page = nullptr;
 	WIN window(DB_PAGE_SPACE, -1);
 	fetch_page(!getInfo, relPages->rel_index_root, pag_root, &window, &page);
 
 	for (USHORT i = 0; i < page->irt_count; i++)
 	{
-		if (page->irt_rpt[i].isEmpty())
+		if (!page->irt_rpt[i].getRoot())
 			continue;
 
 		MetaName index;

src/utilities/gstat/dba.epp

@@ -1566,11 +1566,12 @@ static void analyze_index( const dba_rel* relation, dba_idx* index)
 
 	const index_root_page* index_root = (const index_root_page*) db_read(relation->rel_index_root);
 
-	if (index_root->irt_count <= index->idx_id || index_root->irt_rpt[index->idx_id].isEmpty())
+	if (index_root->irt_count <= index->idx_id)
 		return;
 
-	ULONG page = index_root->irt_rpt[index->idx_id].irt_root;
-	fb_assert(page);
+	ULONG page = index_root->irt_rpt[index->idx_id].getRoot();
+	if (!page)
+		return;
 
 	// CVC: The two const_cast's for bucket can go away if BTreeNode's functions
 	// are overloaded for constness. They don't modify bucket and pointer's contents.