cubedata.h

Go to the documentation of this file.

/* contrib/cube/cubedata.h */

/*
 * This limit is pretty arbitrary, but don't make it so large that you
 * risk overflow in sizing calculations.
 */
#define CUBE_MAX_DIM (100)

typedef struct NDBOX
{
    /* varlena header (do not touch directly!) */
    int32       vl_len_;

    /*----------
     * Header contains info about NDBOX. For binary compatibility with old
     * versions, it is defined as "unsigned int".
     *
     * Following information is stored:
     *
     *  bits 0-7  : number of cube dimensions;
     *  bits 8-30 : unused, initialize to zero;
     *  bit  31   : point flag. If set, the upper right coordinates are not
     *              stored, and are implicitly the same as the lower left
     *              coordinates.
     *----------
     */
    unsigned int header;

    /*
     * The lower left coordinates for each dimension come first, followed by
     * upper right coordinates unless the point flag is set.
     */
    double      x[FLEXIBLE_ARRAY_MEMBER];
} NDBOX;

/* NDBOX access macros */
#define POINT_BIT           0x80000000
#define DIM_MASK            0x7fffffff

#define IS_POINT(cube)      ( ((cube)->header & POINT_BIT) != 0 )
#define SET_POINT_BIT(cube) ( (cube)->header |= POINT_BIT )
#define DIM(cube)           ( (cube)->header & DIM_MASK )
#define SET_DIM(cube, _dim) ( (cube)->header = ((cube)->header & ~DIM_MASK) | (_dim) )

#define LL_COORD(cube, i) ( (cube)->x[i] )
#define UR_COORD(cube, i) ( IS_POINT(cube) ? (cube)->x[i] : (cube)->x[(i) + DIM(cube)] )

#define POINT_SIZE(_dim)    (offsetof(NDBOX, x) + sizeof(double)*(_dim))
#define CUBE_SIZE(_dim)     (offsetof(NDBOX, x) + sizeof(double)*(_dim)*2)

/* fmgr interface macros */
#define DatumGetNDBOX(x)    ((NDBOX *) PG_DETOAST_DATUM(x))
#define PG_GETARG_NDBOX(x)  DatumGetNDBOX(PG_GETARG_DATUM(x))
#define PG_RETURN_NDBOX(x)  PG_RETURN_POINTER(x)

/* GiST operator strategy numbers */
#define CubeKNNDistanceCoord            15  /* ~> */
#define CubeKNNDistanceTaxicab          16  /* <#> */
#define CubeKNNDistanceEuclid           17  /* <-> */
#define CubeKNNDistanceChebyshev        18  /* <=> */

/* in cubescan.l */
extern int  cube_yylex(void);
extern void cube_yyerror(NDBOX **result, const char *message) pg_attribute_noreturn();
extern void cube_scanner_init(const char *str);
extern void cube_scanner_finish(void);

/* in cubeparse.y */
extern int  cube_yyparse(NDBOX **result);