Transaction log manager core code.

It doesn't work currently but also don't break anything -:)

src/include/access/rmgr.h

@@ -0,0 +1,34 @@
+/*
+ *
+ * rmgr.h
+ *
+ * Resource managers description table
+ *
+ */
+#ifndef RMGR_H
+#define RMGR_H
+
+typedef uint8	RmgrId;
+
+typedef struct RmgrData
+{
+	char	   *rm_name;
+	char	   *(*rm_redo) ();	/* REDO(XLogRecPtr rptr) */
+	char	   *(*rm_undo) ();	/* UNDO(XLogRecPtr rptr) */
+} RmgrData;
+
+extern RmgrData	   *RmgrTable;
+
+/*
+ * Built-in resource managers
+ */
+#define	RM_XLOG_ID				0
+#define	RM_XACT_ID				1
+#define	RM_HEAP_ID				2
+#define	RM_BTREE_ID				3
+#define	RM_HASH_ID				4
+#define	RM_RTREE_ID				5
+#define	RM_GIST_ID				6
+#define	RM_MAX_ID				RM_GIST_ID
+
+#endif	 /* RMGR_H */