*
**********************************************************************
* $Log$
+ * Revision 1.15 2003/10/27 20:13:05 strk
+ * Made GeomUnion release memory soon, Added fastunion support functions
+ *
* Revision 1.14 2003/10/24 21:52:35 strk
* Modified strcmp-based if-else with switch-case in GEOS2POSTGIS()
* using new GEOSGeometryTypeId() interface.
#include "postgis.h"
#include "utils/elog.h"
+#include "utils/array.h"
#include "access/gist.h"
#include "access/itup.h"
Datum boundary(PG_FUNCTION_ARGS);
Datum symdifference(PG_FUNCTION_ARGS);
Datum geomunion(PG_FUNCTION_ARGS);
+Datum unite_sfunc(PG_FUNCTION_ARGS);
+Datum unite_finalfunc(PG_FUNCTION_ARGS);
Datum issimple(PG_FUNCTION_ARGS);
}
+/*
+ * Resize an ArrayType of 1 dimension to contain num (Pointer *) elements
+ * array will be repalloc'ed
+ */
+static ArrayType *
+resize_ptrArrayType(ArrayType *a, int num)
+{
+ int nelems = ArrayGetNItems(ARR_NDIM(a), ARR_DIMS(a));
+ int nbytes = ARR_OVERHEAD(1) + sizeof(Pointer *) * num;
+
+ if (num == nelems) return a;
+
+ a = (ArrayType *) repalloc(a, nbytes);
+
+ a->size = nbytes;
+ a->ndim = 1;
+
+ *((int *) ARR_DIMS(a)) = num;
+ return a;
+}
+
+
+/*
+ * This is the state function for union/fastunite/geomunion
+ * aggregate (still discussing the name). Will have
+ * as input an array of Geometry pointers and a Geometry.
+ * Will DETOAST given geometry and put a pointer to it
+ * in the given array. DETOASTED value is first copied
+ * to a safe memory context to avoid premature deletion.
+ *
+ * WARNING: array resize is not checked for memory
+ * context. Might use instable memory!! --strk(TODO);
+ *
+ */
+PG_FUNCTION_INFO_V1(unite_sfunc);
+Datum unite_sfunc(PG_FUNCTION_ARGS)
+{
+ ArrayType *array;
+ int nelems;
+ Datum datum;
+ GEOMETRY *geom, *tmpgeom;
+ ArrayType *result;
+ Pointer **pointers;
+#ifdef USE_BOGUS_MEMORY_CONTEXT_SWITCHING
+ MemoryContext oldcontext;
+#endif
+
+ array = (ArrayType *) PG_GETARG_ARRAYTYPE_P(0);
+ nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+
+ datum = PG_GETARG_DATUM(1);
+ // Do nothing, return state array
+ if ( (Pointer *)datum == NULL )
+ {
+ elog(NOTICE, "unite_sfunc: NULL geom, nelems=%d", nelems);
+ PG_RETURN_ARRAYTYPE_P(array);
+ }
+
+ /*
+ * Find a way to directly detoast datum in
+ * flinfo->fcinfo->fn_mcxt context.
+ * ( this way we'll reduce a memory copy I guess)
+ * --strk(TODO);
+ */
+#ifdef USE_BOGUS_MEMORY_CONTEXT_SWITCHING
+ oldcontext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
+ geom = (GEOMETRY *)PG_DETOAST_DATUM(datum);
+ MemoryContextSwitchTo(oldcontext);
+#else
+ tmpgeom = (GEOMETRY *)PG_DETOAST_DATUM(datum);
+ geom = (GEOMETRY *) MemoryContextAlloc(
+ fcinfo->flinfo->fn_mcxt, tmpgeom->size);
+ memcpy(geom, tmpgeom, tmpgeom->size);
+ if ( (GEOMETRY *)datum != tmpgeom ) pfree(tmpgeom);
+#endif
+
+ // Add given geometry to state array
+ nelems++;
+ //elog(NOTICE, "unite_sfunc: adding %p, nelems=%d", geom, nelems);
+
+ /*
+ * Might use a more optimized version instead of repalloc'ing
+ * at every iteration. This is not the bottleneck anyway.
+ *
+ * WARNING: should use fcinfo->flinfo->fn_mcxt
+ * memory context for the array too!
+ * --strk(TODO);
+ */
+ result = resize_ptrArrayType(array, nelems);
+
+ pointers = (Pointer **)ARR_DATA_PTR(result);
+ pointers[nelems-1] = (Pointer *)geom;
+
+ PG_RETURN_ARRAYTYPE_P(result);
+
+}
+
+/*
+ * This is the final function for union/fastunite/geomunion
+ * aggregate (still discussing the name). Will have
+ * as input an array of Geometry pointers.
+ * Will iteratively call GEOSUnion on the GEOS-converted
+ * versions of them and return PGIS-converted version back.
+ * Changing combination order *might* speed up performance.
+ *
+ * Geometries in the array are pfree'd as soon as possible.
+ *
+ */
+PG_FUNCTION_INFO_V1(unite_finalfunc);
+Datum unite_finalfunc(PG_FUNCTION_ARGS)
+{
+ ArrayType *array;
+ int is3d = 0;
+ int nelems, i;
+ static int call=1;
+ GEOMETRY **geoms, *result, *pgis_geom;
+ Geometry *g1, *g2, *geos_result;
+
+ call++;
+
+ array = (ArrayType *) PG_GETARG_ARRAYTYPE_P(0);
+
+ nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+
+ //elog(NOTICE, "unite_finalfunc: number of elements: %d", nelems);
+
+ if ( nelems == 0 ) PG_RETURN_NULL();
+
+ geoms = (GEOMETRY **)ARR_DATA_PTR(array);
+
+ /* One-element union is the element itself */
+ if ( nelems == 1 ) PG_RETURN_POINTER(geoms[0]);
+
+ /* Ok, we really need geos now ;) */
+ initGEOS(MAXIMUM_ALIGNOF);
+
+ if ( geoms[0]->is3d ) is3d = 1;
+ geos_result = POSTGIS2GEOS(geoms[0]);
+ for (i=1; i<nelems; i++)
+ {
+ pgis_geom = geoms[i];
+
+ g1 = POSTGIS2GEOS(pgis_geom);
+ /*
+ * If we free this memory now we'll have
+ * more space for the growing result geometry.
+ * We don't need it anyway.
+ */
+ pfree(pgis_geom);
+
+ elog(NOTICE, "unite_finalfunc(%d): adding geom %d to union", i, call);
+ g2 = GEOSUnion(g1,geos_result);
+ if ( g2 == NULL )
+ {
+ GEOSdeleteGeometry(g1);
+ GEOSdeleteGeometry(geos_result);
+ elog(ERROR,"GEOS union() threw an error!");
+ }
+ GEOSdeleteGeometry(g1);
+ GEOSdeleteGeometry(geos_result);
+ geos_result = g2;
+ }
+
+ result = GEOS2POSTGIS(geos_result, is3d);
+ GEOSdeleteGeometry(geos_result);
+ if ( result == NULL )
+ {
+ elog(ERROR, "GEOS2POSTGIS returned an error");
+ PG_RETURN_NULL(); //never get here
+ }
+
+ compressType(result);
+
+ PG_RETURN_POINTER(result);
+
+}
+
//select geomunion('POLYGON((0 0, 10 0, 10 10, 0 10, 0 0))','POLYGON((5 5, 15 5, 15 7, 5 7, 5 5))');
PG_FUNCTION_INFO_V1(geomunion);
//elog(NOTICE,"g3=%s",GEOSasText(g3));
- //pfree(geom1);
- //pfree(geom2);
+ PG_FREE_IF_COPY(geom1, 0);
+ PG_FREE_IF_COPY(geom2, 1);
+ GEOSdeleteGeometry(g1);
+ GEOSdeleteGeometry(g2);
if (g3 == NULL)
{
- GEOSdeleteGeometry(g1);
- GEOSdeleteGeometry(g2);
elog(ERROR,"GEOS union() threw an error!");
PG_RETURN_NULL(); //never get here
}
result = GEOS2POSTGIS(g3, geom1->is3d || geom2->is3d);
- GEOSdeleteGeometry(g1);
- GEOSdeleteGeometry(g2);
GEOSdeleteGeometry(g3);
if (result == NULL)
projects / postgis / commitdiff