ST_Union: allocate correct size of memory in right context

Thanks Raul for finding the cause.

References #4382
Closes https://github.com/postgis/postgis/pull/397

git-svn-id: http://svn.osgeo.org/postgis/trunk@17406 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/postgis/lwgeom_geos.c b/postgis/lwgeom_geos.c
index 8071b58ae71e99292f3d9ecde0d56fb53cb02e59..16a64ffae5a11e54a6f99dc7c50775f3ccf6937e 100644 (file)
--- a/postgis/lwgeom_geos.c
+++ b/postgis/lwgeom_geos.c
@@ -523,6 +523,7 @@ PG_FUNCTION_INFO_V1(pgis_geometry_union_transfn);
 Datum pgis_geometry_union_transfn(PG_FUNCTION_ARGS)
 {
        MemoryContext aggcontext;
+       MemoryContext old;
        UnionBuildState *state;
        GSERIALIZED *gser_in;
        uint32_t curgeom;
@@ -541,7 +542,7 @@ Datum pgis_geometry_union_transfn(PG_FUNCTION_ARGS)
        }
        else
        {
-               MemoryContext old = MemoryContextSwitchTo(aggcontext);
+               old = MemoryContextSwitchTo(aggcontext);
                state = (UnionBuildState *)palloc(sizeof(UnionBuildState));
 
                state->mcontext = aggcontext;
@@ -560,7 +561,9 @@ Datum pgis_geometry_union_transfn(PG_FUNCTION_ARGS)
        /* do we have geometry to push? */
        if (!PG_ARGISNULL(1))
        {
-               gser_in = PG_GETARG_GSERIALIZED_P(1);
+               old = MemoryContextSwitchTo(state->mcontext);
+               gser_in = PG_GETARG_GSERIALIZED_P_COPY(1);
+               MemoryContextSwitchTo(old);
 
                if (state->ngeoms > 0)
                {
@@ -572,14 +575,15 @@ Datum pgis_geometry_union_transfn(PG_FUNCTION_ARGS)
 
                if (!gserialized_is_empty(gser_in))
                {
-                       MemoryContext old = MemoryContextSwitchTo(aggcontext);
                        if (state->ngeoms == 0)
                        {
                                state->srid = gserialized_get_srid(gser_in);
                                state->is3d = gserialized_has_z(gser_in);
                        }
 
+                       old = MemoryContextSwitchTo(state->mcontext);
                        g = POSTGIS2GEOS(gser_in);
+                       MemoryContextSwitchTo(old);
 
                        if (!g)
                        {
@@ -593,12 +597,13 @@ Datum pgis_geometry_union_transfn(PG_FUNCTION_ARGS)
 
                        if (state->ngeoms > state->alen)
                        {
+                               old = MemoryContextSwitchTo(state->mcontext);
                                state->alen *= 2;
-                               state->geoms = repalloc(state->geoms, state->alen);
+                               state->geoms = repalloc(state->geoms, sizeof(GEOSGeometry *) * state->alen);
+                               MemoryContextSwitchTo(old);
                        }
 
                        state->geoms[curgeom] = g;
-                       MemoryContextSwitchTo(old);
                }
                else
                {