btree_int2.c

/*
 * contrib/btree_gist/btree_int2.c
 */
#include "postgres.h"

#include "btree_gist.h"
#include "btree_utils_num.h"

typedef struct int16key
{
    int16        lower;
    int16        upper;
} int16KEY;

/*
** int16 ops
*/
PG_FUNCTION_INFO_V1(gbt_int2_compress);
PG_FUNCTION_INFO_V1(gbt_int2_fetch);
PG_FUNCTION_INFO_V1(gbt_int2_union);
PG_FUNCTION_INFO_V1(gbt_int2_picksplit);
PG_FUNCTION_INFO_V1(gbt_int2_consistent);
PG_FUNCTION_INFO_V1(gbt_int2_distance);
PG_FUNCTION_INFO_V1(gbt_int2_penalty);
PG_FUNCTION_INFO_V1(gbt_int2_same);

static bool
gbt_int2gt(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const int16 *) a) > *((const int16 *) b));
}
static bool
gbt_int2ge(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const int16 *) a) >= *((const int16 *) b));
}
static bool
gbt_int2eq(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const int16 *) a) == *((const int16 *) b));
}
static bool
gbt_int2le(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const int16 *) a) <= *((const int16 *) b));
}
static bool
gbt_int2lt(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const int16 *) a) < *((const int16 *) b));
}

static int
gbt_int2key_cmp(const void *a, const void *b, FmgrInfo *flinfo)
{
    int16KEY   *ia = (int16KEY *) (((const Nsrt *) a)->t);
    int16KEY   *ib = (int16KEY *) (((const Nsrt *) b)->t);

    if (ia->lower == ib->lower)
    {
        if (ia->upper == ib->upper)
            return 0;

        return (ia->upper > ib->upper) ? 1 : -1;
    }

    return (ia->lower > ib->lower) ? 1 : -1;
}

static float8
gbt_int2_dist(const void *a, const void *b, FmgrInfo *flinfo)
{
    return GET_FLOAT_DISTANCE(int16, a, b);
}


static const gbtree_ninfo tinfo =
{
    gbt_t_int2,
    sizeof(int16),
    4,                            /* sizeof(gbtreekey4) */
    gbt_int2gt,
    gbt_int2ge,
    gbt_int2eq,
    gbt_int2le,
    gbt_int2lt,
    gbt_int2key_cmp,
    gbt_int2_dist
};


PG_FUNCTION_INFO_V1(int2_dist);
Datum
int2_dist(PG_FUNCTION_ARGS)
{
    int16        a = PG_GETARG_INT16(0);
    int16        b = PG_GETARG_INT16(1);
    int16        r;
    int16        ra;

    r = a - b;
    ra = Abs(r);

    /* Overflow check. */
    if (ra < 0 || (!SAMESIGN(a, b) && !SAMESIGN(r, a)))
        ereport(ERROR,
                (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
                 errmsg("smallint out of range")));

    PG_RETURN_INT16(ra);
}


/**************************************************
 * int16 ops
 **************************************************/


Datum
gbt_int2_compress(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);

    PG_RETURN_POINTER(gbt_num_compress(entry, &tinfo));
}

Datum
gbt_int2_fetch(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);

    PG_RETURN_POINTER(gbt_num_fetch(entry, &tinfo));
}

Datum
gbt_int2_consistent(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
    int16        query = PG_GETARG_INT16(1);
    StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);

    /* Oid        subtype = PG_GETARG_OID(3); */
    bool       *recheck = (bool *) PG_GETARG_POINTER(4);
    int16KEY   *kkk = (int16KEY *) DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    /* All cases served by this function are exact */
    *recheck = false;

    key.lower = (GBT_NUMKEY *) &kkk->lower;
    key.upper = (GBT_NUMKEY *) &kkk->upper;

    PG_RETURN_BOOL(
                   gbt_num_consistent(&key, (void *) &query, &strategy, GIST_LEAF(entry), &tinfo, fcinfo->flinfo)
        );
}


Datum
gbt_int2_distance(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
    int16        query = PG_GETARG_INT16(1);

    /* Oid        subtype = PG_GETARG_OID(3); */
    int16KEY   *kkk = (int16KEY *) DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    key.lower = (GBT_NUMKEY *) &kkk->lower;
    key.upper = (GBT_NUMKEY *) &kkk->upper;

    PG_RETURN_FLOAT8(
                     gbt_num_distance(&key, (void *) &query, GIST_LEAF(entry), &tinfo, fcinfo->flinfo)
        );
}


Datum
gbt_int2_union(PG_FUNCTION_ARGS)
{
    GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
    void       *out = palloc(sizeof(int16KEY));

    *(int *) PG_GETARG_POINTER(1) = sizeof(int16KEY);
    PG_RETURN_POINTER(gbt_num_union((void *) out, entryvec, &tinfo, fcinfo->flinfo));
}


Datum
gbt_int2_penalty(PG_FUNCTION_ARGS)
{
    int16KEY   *origentry = (int16KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
    int16KEY   *newentry = (int16KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key);
    float       *result = (float *) PG_GETARG_POINTER(2);

    penalty_num(result, origentry->lower, origentry->upper, newentry->lower, newentry->upper);

    PG_RETURN_POINTER(result);
}

Datum
gbt_int2_picksplit(PG_FUNCTION_ARGS)
{
    PG_RETURN_POINTER(gbt_num_picksplit(
                                        (GistEntryVector *) PG_GETARG_POINTER(0),
                                        (GIST_SPLITVEC *) PG_GETARG_POINTER(1),
                                        &tinfo, fcinfo->flinfo
                                        ));
}

Datum
gbt_int2_same(PG_FUNCTION_ARGS)
{
    int16KEY   *b1 = (int16KEY *) PG_GETARG_POINTER(0);
    int16KEY   *b2 = (int16KEY *) PG_GETARG_POINTER(1);
    bool       *result = (bool *) PG_GETARG_POINTER(2);

    *result = gbt_num_same((void *) b1, (void *) b2, &tinfo, fcinfo->flinfo);
    PG_RETURN_POINTER(result);
}