lwgeom_accum.c

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/**********************************************************************
 *
 * PostGIS - Spatial Types for PostgreSQL
 * http://postgis.net
 *
 * PostGIS is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * PostGIS is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with PostGIS.  If not, see <http://www.gnu.org/licenses/>.
 *
 **********************************************************************
 *
 * Copyright 2009 Paul Ramsey <pramsey@opengeo.org>
 *
 **********************************************************************/


#include "postgres.h"
#include "fmgr.h"
#include "funcapi.h"
#include "access/tupmacs.h"
#include "utils/datum.h"
#include "utils/array.h"
#include "utils/lsyscache.h"

#include "../postgis_config.h"

#include "liblwgeom.h"
#include "lwgeom_geos.h"
#include "lwgeom_pg.h"
#include "lwgeom_transform.h"

/* Local prototypes */
Datum PGISDirectFunctionCall1(PGFunction func, Datum arg1);
Datum PGISDirectFunctionCall2(PGFunction func, Datum arg1, Datum arg2);
Datum pgis_geometry_accum_transfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_accum_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_union_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_collect_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_polygonize_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_makeline_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_clusterintersecting_finalfn(PG_FUNCTION_ARGS);
Datum pgis_geometry_clusterwithin_finalfn(PG_FUNCTION_ARGS);
Datum pgis_abs_in(PG_FUNCTION_ARGS);
Datum pgis_abs_out(PG_FUNCTION_ARGS);

/* External prototypes */
Datum pgis_union_geometry_array(PG_FUNCTION_ARGS);
Datum LWGEOM_collect_garray(PG_FUNCTION_ARGS);
Datum polygonize_garray(PG_FUNCTION_ARGS);
Datum clusterintersecting_garray(PG_FUNCTION_ARGS);
Datum cluster_within_distance_garray(PG_FUNCTION_ARGS);
Datum LWGEOM_makeline_garray(PG_FUNCTION_ARGS);


typedef struct
{
        ArrayBuildState *a;
        Datum data;
}
pgis_abs;



PG_FUNCTION_INFO_V1(pgis_abs_in);
Datum
pgis_abs_in(PG_FUNCTION_ARGS)
{
        ereport(ERROR,(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                       errmsg("function %s not implemented", __func__)));
        PG_RETURN_POINTER(NULL);
}
PG_FUNCTION_INFO_V1(pgis_abs_out);
Datum
pgis_abs_out(PG_FUNCTION_ARGS)
{
        ereport(ERROR,(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                       errmsg("function %s not implemented", __func__)));
        PG_RETURN_POINTER(NULL);
}

PG_FUNCTION_INFO_V1(pgis_geometry_accum_transfn);
Datum
pgis_geometry_accum_transfn(PG_FUNCTION_ARGS)
{
        Oid arg1_typeid = get_fn_expr_argtype(fcinfo->flinfo, 1);
        MemoryContext aggcontext;
        ArrayBuildState *state;
        pgis_abs *p;
        Datum elem;

        if (arg1_typeid == InvalidOid)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("could not determine input data type")));

        if ( ! AggCheckCallContext(fcinfo, &aggcontext) )
        {
                /* cannot be called directly because of dummy-type argument */
                elog(ERROR, "%s called in non-aggregate context", __func__);
                aggcontext = NULL;  /* keep compiler quiet */
        }

        if ( PG_ARGISNULL(0) )
        {
                p = (pgis_abs*) palloc(sizeof(pgis_abs));
                p->a = NULL;
                p->data = (Datum) NULL;

                if (PG_NARGS() == 3)
                {
                        Datum argument = PG_GETARG_DATUM(2);
                        Oid dataOid = get_fn_expr_argtype(fcinfo->flinfo, 2);
                        MemoryContext old = MemoryContextSwitchTo(aggcontext);

                        p->data = datumCopy(argument, get_typbyval(dataOid), get_typlen(dataOid));

                        MemoryContextSwitchTo(old);
                }
        }
        else
        {
                p = (pgis_abs*) PG_GETARG_POINTER(0);
        }
        state = p->a;
        elem = PG_ARGISNULL(1) ? (Datum) 0 : PG_GETARG_DATUM(1);
        state = accumArrayResult(state,
                                 elem,
                                 PG_ARGISNULL(1),
                                 arg1_typeid,
                                 aggcontext);
        p->a = state;

        PG_RETURN_POINTER(p);
}



Datum pgis_accum_finalfn(pgis_abs *p, MemoryContext mctx, FunctionCallInfo fcinfo);

Datum
pgis_accum_finalfn(pgis_abs *p, MemoryContext mctx, FunctionCallInfo fcinfo)
{
        int dims[1];
        int lbs[1];
        ArrayBuildState *state;
        Datum result;

        /* cannot be called directly because of internal-type argument */
        Assert(fcinfo->context &&
               (IsA(fcinfo->context, AggState) ||
                IsA(fcinfo->context, WindowAggState))
               );

        state = p->a;
        dims[0] = state->nelems;
        lbs[0] = 1;
        result = makeMdArrayResult(state, 1, dims, lbs, mctx, false);
        return result;
}

PG_FUNCTION_INFO_V1(pgis_geometry_accum_finalfn);
Datum
pgis_geometry_accum_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();   /* returns null iff no input values */

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        result = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);

        PG_RETURN_DATUM(result);

}

PG_FUNCTION_INFO_V1(pgis_geometry_union_finalfn);
Datum
pgis_geometry_union_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();   /* returns null iff no input values */

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall1( pgis_union_geometry_array, geometry_array );
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}

PG_FUNCTION_INFO_V1(pgis_geometry_collect_finalfn);
Datum
pgis_geometry_collect_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();   /* returns null iff no input values */

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall1( LWGEOM_collect_garray, geometry_array );
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}


PG_FUNCTION_INFO_V1(pgis_geometry_polygonize_finalfn);
Datum
pgis_geometry_polygonize_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();   /* returns null iff no input values */

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall1( polygonize_garray, geometry_array );
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}

PG_FUNCTION_INFO_V1(pgis_geometry_makeline_finalfn);
Datum
pgis_geometry_makeline_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();   /* returns null iff no input values */

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall1( LWGEOM_makeline_garray, geometry_array );
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}

PG_FUNCTION_INFO_V1(pgis_geometry_clusterintersecting_finalfn);
Datum
pgis_geometry_clusterintersecting_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();

        p = (pgis_abs*) PG_GETARG_POINTER(0);
        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall1( clusterintersecting_garray, geometry_array );
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}

PG_FUNCTION_INFO_V1(pgis_geometry_clusterwithin_finalfn);
Datum
pgis_geometry_clusterwithin_finalfn(PG_FUNCTION_ARGS)
{
        pgis_abs *p;
        Datum result = 0;
        Datum geometry_array = 0;

        if (PG_ARGISNULL(0))
                PG_RETURN_NULL();

        p = (pgis_abs*) PG_GETARG_POINTER(0);

        if (!p->data)
        {
                elog(ERROR, "Tolerance not defined");
                PG_RETURN_NULL();
        }

        geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
        result = PGISDirectFunctionCall2( cluster_within_distance_garray, geometry_array, p->data);
        if (!result)
                PG_RETURN_NULL();

        PG_RETURN_DATUM(result);
}

Datum
PGISDirectFunctionCall1(PGFunction func, Datum arg1)
{
#if POSTGIS_PGSQL_VERSION < 120
        FunctionCallInfoData fcinfo;
        Datum           result;


        InitFunctionCallInfoData(fcinfo, NULL, 1, InvalidOid, NULL, NULL);


        fcinfo.arg[0] = arg1;
        fcinfo.argnull[0] = false;

        result = (*func) (&fcinfo);

        /* Check for null result, returning a "NULL" Datum if indicated */
        if (fcinfo.isnull)
                return (Datum) 0;

        return result;
#else
        LOCAL_FCINFO(fcinfo, 1);
        Datum result;

        InitFunctionCallInfoData(*fcinfo, NULL, 1, InvalidOid, NULL, NULL);

        fcinfo->args[0].value = arg1;
        fcinfo->args[0].isnull = false;

        result = (*func)(fcinfo);

        /* Check for null result, returning a "NULL" Datum if indicated */
        if (fcinfo->isnull)
                return (Datum)0;

        return result;
#endif /* POSTGIS_PGSQL_VERSION < 120 */
}

Datum
PGISDirectFunctionCall2(PGFunction func, Datum arg1, Datum arg2)
{
#if POSTGIS_PGSQL_VERSION < 120
        FunctionCallInfoData fcinfo;
        Datum           result;

        InitFunctionCallInfoData(fcinfo, NULL, 2, InvalidOid, NULL, NULL);

        fcinfo.arg[0] = arg1;
        fcinfo.arg[1] = arg2;
        fcinfo.argnull[0] = false;
        fcinfo.argnull[1] = false;

        result = (*func) (&fcinfo);

        /* Check for null result, returning a "NULL" Datum if indicated */
        if (fcinfo.isnull)
                return (Datum) 0;

        return result;
#else
        LOCAL_FCINFO(fcinfo, 2);
        Datum result;

        InitFunctionCallInfoData(*fcinfo, NULL, 2, InvalidOid, NULL, NULL);

        fcinfo->args[0].value = arg1;
        fcinfo->args[1].value = arg2;
        fcinfo->args[0].isnull = false;
        fcinfo->args[1].isnull = false;

        result = (*func)(fcinfo);

        /* Check for null result, returning a "NULL" Datum if indicated */
        if (fcinfo->isnull)
                return (Datum)0;

        return result;
#endif /* POSTGIS_PGSQL_VERSION < 120 */
}