From f556e4b4664e9774b664ab40d0134218e5f172dd Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@keybit.net>
Date: Tue, 12 Jun 2012 09:09:06 +0000
Subject: [PATCH] Add GEOMETRYCOLLECTION input support for ST_MakeValid (#1719)

git-svn-id: http://svn.osgeo.org/postgis/trunk@9892 b70326c6-7e19-0410-871a-916f4a2858ee
---
 NEWS                          |  1 +
 liblwgeom/cunit/cu_clean.c    | 19 ++++++++++
 liblwgeom/lwgeom_geos_clean.c | 66 +++++++++++++++++++++++++++++++++++
 3 files changed, 86 insertions(+)

diff --git a/NEWS b/NEWS
index 8d05901aa..2b637dd34 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ PostGIS 2.1.0
   - ST_Raster2WorldCoord, ST_World2RasterCoord (Bborie Park / UC Davis)
   - Tiger Geocoder - Tiger 2011 loader (Regina Obe / Paragon Corporation) 
     Funded by Hunter Systems Group
+  - GEOMETRYCOLLECTION support for ST_MakeValid (Sandro Santilli / Vizzuality)
 
 * Enhancements *
 
diff --git a/liblwgeom/cunit/cu_clean.c b/liblwgeom/cunit/cu_clean.c
index 367659509..be771db8c 100644
--- a/liblwgeom/cunit/cu_clean.c
+++ b/liblwgeom/cunit/cu_clean.c
@@ -21,6 +21,7 @@ static void test_lwgeom_make_valid(void)
 #if POSTGIS_GEOS_VERSION >= 33
 	LWGEOM *gin, *gout;
 	int ret;
+	char *ewkt;
 
 	/* Because i don't trust that much prior tests...  ;) */
 	cu_error_msg_reset();
@@ -42,6 +43,24 @@ static void test_lwgeom_make_valid(void)
 	lwgeom_free(gout);
 	lwgeom_free(gin);
 
+
+	gin = lwgeom_from_wkt(
+"GEOMETRYCOLLECTION(LINESTRING(0 0, 0 0), POLYGON((0 0, 10 10, 10 0, 0 10, 0 0)), LINESTRING(10 0, 10 10))",
+		LW_PARSER_CHECK_NONE);
+	CU_ASSERT(gin);
+
+	gout = lwgeom_make_valid(gin);
+	CU_ASSERT(gout);
+
+	ewkt = lwgeom_to_ewkt(gout);
+	printf("c = %s\n", ewkt);
+	CU_ASSERT_STRING_EQUAL(ewkt,
+"GEOMETRYCOLLECTION(POINT(0 0),MULTIPOLYGON(((5 5,0 0,0 10,5 5)),((5 5,10 10,10 0,5 5))),LINESTRING(10 0,10 10))");
+	lwfree(ewkt);
+
+	lwgeom_free(gout);
+	lwgeom_free(gin);
+
 #endif /* POSTGIS_GEOS_VERSION >= 33 */
 }
 
diff --git a/liblwgeom/lwgeom_geos_clean.c b/liblwgeom/lwgeom_geos_clean.c
index 887fc745c..f0ec20faa 100644
--- a/liblwgeom/lwgeom_geos_clean.c
+++ b/liblwgeom/lwgeom_geos_clean.c
@@ -613,6 +613,7 @@ LWGEOM_GEOS_makeValidPolygon(const GEOSGeometry* gin)
 			/* cleanup and throw */
 			GEOSGeom_destroy(geos_cut_edges);
 			GEOSGeom_destroy(geos_area);
+			/* TODO: Shouldn't this be an lwerror ? */
 			lwnotice("GEOSDifference() threw an error: %s",
 			         lwgeom_geos_errmsg);
 			return NULL;
@@ -664,6 +665,7 @@ LWGEOM_GEOS_makeValidPolygon(const GEOSGeometry* gin)
 		if ( ! gout )   /* an exception again */
 		{
 			/* cleanup and throw */
+			/* TODO: Shouldn't this be an lwerror ? */
 			lwnotice("GEOSGeom_createCollection() threw an error: %s",
 			         lwgeom_geos_errmsg);
 			/* TODO: cleanup! */
@@ -792,6 +794,58 @@ LWGEOM_GEOS_makeValidMultiLine(const GEOSGeometry* gin)
 	return gout;
 }
 
+static GEOSGeometry* LWGEOM_GEOS_makeValid(const GEOSGeometry*);
+
+/*
+ * We expect initGEOS being called already.
+ * Will return NULL on error (expect error handler being called by then)
+ */
+static GEOSGeometry*
+LWGEOM_GEOS_makeValidCollection(const GEOSGeometry* gin)
+{
+	int nvgeoms;
+	GEOSGeometry **vgeoms;
+	GEOSGeom gout;
+	unsigned int i;
+
+	nvgeoms = GEOSGetNumGeometries(gin);
+	if ( nvgeoms == -1 ) {
+		lwerror("GEOSGetNumGeometries: %s", lwgeom_geos_errmsg);
+		return 0;
+	}
+
+	vgeoms = lwalloc( sizeof(GEOSGeometry*) * nvgeoms );
+	if ( ! vgeoms ) {
+		lwerror("LWGEOM_GEOS_makeValidCollection: out of memory");
+		return 0;
+	}
+
+	for ( i=0; i<nvgeoms; ++i ) {
+		vgeoms[i] = LWGEOM_GEOS_makeValid( GEOSGetGeometryN(gin, i) );
+		if ( ! vgeoms[i] ) {
+			while (i--) GEOSGeom_destroy(vgeoms[i]);
+			lwfree(vgeoms);
+			/* we expect lwerror being called already by makeValid */
+			return NULL;
+		}
+	}
+
+	/* Collect areas and lines (if any line) */
+	gout = GEOSGeom_createCollection(GEOS_GEOMETRYCOLLECTION, vgeoms, nvgeoms);
+	lwfree(vgeoms);
+	if ( ! gout )   /* an exception again */
+	{
+		/* cleanup and throw */
+		for ( i=0; i<nvgeoms; ++i ) GEOSGeom_destroy(vgeoms[i]);
+		lwerror("GEOSGeom_createCollection() threw an error: %s",
+		         lwgeom_geos_errmsg);
+		return NULL;
+	}
+
+	return gout;
+
+}
+
 
 static GEOSGeometry*
 LWGEOM_GEOS_makeValid(const GEOSGeometry* gin)
@@ -873,6 +927,18 @@ LWGEOM_GEOS_makeValid(const GEOSGeometry* gin)
 		break; /* we've done */
 	}
 
+	case GEOS_GEOMETRYCOLLECTION:
+	{
+		gout = LWGEOM_GEOS_makeValidCollection(gin);
+		if ( ! gout )  /* an exception or something */
+		{
+			/* cleanup and throw */
+			lwerror("%s", lwgeom_geos_errmsg);
+			return NULL;
+		}
+		break; /* we've done */
+	}
+
 	default:
 	{
 		char* typname = GEOSGeomType(gin);
-- 
2.50.1