enum jbvType
{
	/* Scalar types */
	jbvNull = 0x0,
	jbvString,
	jbvNumeric,
	jbvBool,
	/* Composite types */
	jbvArray = 0x10,
	jbvObject,
	/* Binary (i.e. struct Jsonb) jbvArray/jbvObject */
	jbvBinary
};
  
struct JsonbValue
{
	enum jbvType	type;			/* Influences sort order */

	union
	{
		Numeric numeric;
		bool		boolean;
		struct
		{
			int			len;
			char	   *val;	/* Not necessarily null-terminated */
		}			string;		/* String primitive type */

		struct
		{
			int			nElems;
			JsonbValue *elems;
			bool		rawScalar;		/* Top-level "raw scalar" array? */
		}			array;		/* Array container type */

		struct
		{
			int			nPairs; /* 1 pair, 2 elements */
			JsonbPair  *pairs;
		}			object;		/* Associative container type */

		struct
		{
			int			len;
			JsonbContainer *data;
		}			binary;		/* Array or object, in on-disk format */
	}			val;
};

  

typedef uint32 JEntry;

#define JENTRY_OFFLENMASK		0x0FFFFFFF
#define JENTRY_TYPEMASK			0x70000000
#define JENTRY_HAS_OFF			0x80000000

/* values stored in the type bits */
#define JENTRY_ISSTRING			0x00000000
#define JENTRY_ISNUMERIC		0x10000000
#define JENTRY_ISBOOL_FALSE		0x20000000
#define JENTRY_ISBOOL_TRUE		0x30000000
#define JENTRY_ISNULL			0x40000000
#define JENTRY_ISCONTAINER		0x50000000		/* array or object */

/*
 * A jsonb array or object node, within a Jsonb Datum.
 *
 * An array has one child for each element, stored in array order.
 *
 * An object has two children for each key/value pair.  The keys all appear
 * first, in key sort order; then the values appear, in an order matching the
 * key order.  This arrangement keeps the keys compact in memory, making a
 * search for a particular key more cache-friendly.
 */
typedef struct JsonbContainer
{
	uint32		header;			/* number of elements or key/value pairs, and
								 * flags */
	JEntry		children[FLEXIBLE_ARRAY_MEMBER];

	/* the data for each child node follows. */
} JsonbContainer;

typedef struct
{
    int32		vl_len_;		/* varlena header (do not touch directly!) */
    JsonbContainer root;
} Jsonb;
/* convenience macros for accessing the root container in a Jsonb datum */
#define JB_ROOT_COUNT(jbp_)		( *(uint32*) VARDATA(jbp_) & JB_CMASK)
#define JB_ROOT_IS_SCALAR(jbp_) ( *(uint32*) VARDATA(jbp_) & JB_FSCALAR)
#define JB_ROOT_IS_OBJECT(jbp_) ( *(uint32*) VARDATA(jbp_) & JB_FOBJECT)
#define JB_ROOT_IS_ARRAY(jbp_)	( *(uint32*) VARDATA(jbp_) & JB_FARRAY)