From f478559d11237dddf9e33f6ffa2b1469c40a1c7e Mon Sep 17 00:00:00 2001
From: Mark Cave-Ayland <mark.cave-ayland@siriusit.co.uk>
Date: Wed, 7 Oct 2009 12:16:04 +0000
Subject: [PATCH] Fix #179: ST_MakeLine and ST_MakeLine_Garry crash server with
 null arrays again. There was another non-NULL safe array iterator within
 LWGEOM_makeline_garray.

git-svn-id: http://svn.osgeo.org/postgis/trunk@4618 b70326c6-7e19-0410-871a-916f4a2858ee
---
 postgis/lwgeom_accum.c           |  4 ++-
 postgis/lwgeom_functions_basic.c | 62 +++++++++++++++++++++-----------
 2 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/postgis/lwgeom_accum.c b/postgis/lwgeom_accum.c
index 05e97d857..cc4ac34dc 100644
--- a/postgis/lwgeom_accum.c
+++ b/postgis/lwgeom_accum.c
@@ -284,7 +284,9 @@ pgis_geometry_makeline_finalfn(PG_FUNCTION_ARGS)
 	p = (pgis_abs*) PG_GETARG_POINTER(0);
 
 	geometry_array = pgis_accum_finalfn(p, CurrentMemoryContext, fcinfo);
-	result = DirectFunctionCall1( LWGEOM_makeline_garray, geometry_array );
+	result = PGISDirectFunctionCall1( LWGEOM_makeline_garray, geometry_array );
+	if (!result)
+		PG_RETURN_NULL();
 
 	PG_RETURN_DATUM(result);
 }
diff --git a/postgis/lwgeom_functions_basic.c b/postgis/lwgeom_functions_basic.c
index 3fd59f6ec..129790fd9 100644
--- a/postgis/lwgeom_functions_basic.c
+++ b/postgis/lwgeom_functions_basic.c
@@ -2156,6 +2156,9 @@ Datum LWGEOM_makeline_garray(PG_FUNCTION_ARGS)
 	size_t offset;
 	int SRID=-1;
 
+	bits8 *bitmap;
+	int bitmask;
+
 	POSTGIS_DEBUG(2, "LWGEOM_makeline_garray called.");
 
 	/* Get input datum */
@@ -2195,34 +2198,51 @@ Datum LWGEOM_makeline_garray(PG_FUNCTION_ARGS)
 	lwpoints = palloc(sizeof(LWGEOM *)*nelems);
 	npoints = 0;
 	offset = 0;
+	bitmap = ARR_NULLBITMAP(array);
+	bitmask = 1;
 	for (i=0; i<nelems; i++)
 	{
-		PG_LWGEOM *geom = (PG_LWGEOM *)(ARR_DATA_PTR(array)+offset);
-		offset += INTALIGN(VARSIZE(geom));
-
-		if ( TYPE_GETTYPE(geom->type) != POINTTYPE ) continue;
-
-		lwpoints[npoints++] =
-		    lwpoint_deserialize(SERIALIZED_FORM(geom));
-
-		/* Check SRID homogeneity */
-		if ( npoints == 1 )
-		{
-			/* Get first geometry SRID */
-			SRID = lwpoints[npoints-1]->SRID;
+		/* Don't do anything for NULL values */  
+		if ((bitmap && (*bitmap & bitmask) != 0) || !bitmap) 
+ 		{ 
+			PG_LWGEOM *geom = (PG_LWGEOM *)(ARR_DATA_PTR(array)+offset);
+			offset += INTALIGN(VARSIZE(geom));
+	
+			if ( TYPE_GETTYPE(geom->type) != POINTTYPE ) continue;
+	
+			lwpoints[npoints++] =
+			lwpoint_deserialize(SERIALIZED_FORM(geom));
+	
+			/* Check SRID homogeneity */
+			if ( npoints == 1 )
+			{
+				/* Get first geometry SRID */
+				SRID = lwpoints[npoints-1]->SRID;
+			}
+			else
+			{
+				if ( lwpoints[npoints-1]->SRID != SRID )
+				{
+					elog(ERROR,
+					"Operation on mixed SRID geometries");
+					PG_RETURN_NULL();
+				}
+			}
+	
+			POSTGIS_DEBUGF(3, "LWGEOM_makeline_garray: element %d deserialized",
+				i);
 		}
-		else
+
+		/* Advance NULL bitmap */
+		if (bitmap)
 		{
-			if ( lwpoints[npoints-1]->SRID != SRID )
+			bitmask <<= 1;
+			if (bitmask == 0x100)
 			{
-				elog(ERROR,
-				     "Operation on mixed SRID geometries");
-				PG_RETURN_NULL();
+				bitmap++;
+				bitmask = 1;
 			}
 		}
-
-		POSTGIS_DEBUGF(3, "LWGEOM_makeline_garray: element %d deserialized",
-		               i);
 	}
 
 	/* Return null on 0-points input array */
-- 
2.50.1