[tracker/IorR-null-support: 3/3] libtracker-data: Add stops and error handling for unsupported null cases

[Philip Van Hoof <pvanhoof src gnome org>]

commit d46929125f4162d24ebad231be2717d93d214727
Author: Philip Van Hoof <philip codeminded be>
Date:   Tue Aug 9 15:28:16 2011 +0200

    libtracker-data: Add stops and error handling for unsupported null cases

 src/libtracker-data/tracker-data-update.c     |    7 +++++++
 src/libtracker-data/tracker-sparql-query.vala |   16 +++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletions(-)
---
diff --git a/src/libtracker-data/tracker-data-update.c b/src/libtracker-data/tracker-data-update.c
index c252455..ddc6b51 100644
--- a/src/libtracker-data/tracker-data-update.c
+++ b/src/libtracker-data/tracker-data-update.c
@@ -3071,6 +3071,13 @@ tracker_data_update_statement (const gchar            *graph,
 	property = tracker_ontologies_get_property_by_uri (predicate);
 	if (property != NULL) {
 		if (object == NULL) {
+			
+			if (property == tracker_ontologies_get_rdf_type ()) {
+				g_set_error (error, TRACKER_SPARQL_ERROR, TRACKER_SPARQL_ERROR_UNSUPPORTED,
+				             "Using 'null' with '%s' is not supported", predicate);
+				return;
+			}
+
 			delete_all_objects (graph, subject, predicate, error);
 		} else {
 			if (tracker_property_get_data_type (property) == TRACKER_PROPERTY_TYPE_RESOURCE) {
diff --git a/src/libtracker-data/tracker-sparql-query.vala b/src/libtracker-data/tracker-sparql-query.vala
index 3040b13..056719e 100644
--- a/src/libtracker-data/tracker-sparql-query.vala
+++ b/src/libtracker-data/tracker-sparql-query.vala
@@ -755,16 +755,25 @@ public class Tracker.Sparql.Query : Object {
 		expect (SparqlTokenType.OPEN_BRACE);
 
 		while (current () != SparqlTokenType.CLOSE_BRACE) {
-			bool is_null; // ignored
+			bool is_null = false;
 
 			if (accept (SparqlTokenType.GRAPH)) {
 				var old_graph = current_graph;
 				current_graph = parse_construct_var_or_term (var_value_map, out is_null);
 
+				if (is_null) {
+					throw get_error ("'null' not supported for graph");
+				}
+
 				expect (SparqlTokenType.OPEN_BRACE);
 
 				while (current () != SparqlTokenType.CLOSE_BRACE) {
 					current_subject = parse_construct_var_or_term (var_value_map, out is_null);
+
+					if (is_null) {
+						throw get_error ("'null' not supported for subject");
+					}
+
 					parse_construct_property_list_not_empty (var_value_map);
 					if (!accept (SparqlTokenType.DOT)) {
 						// no triples following
@@ -779,6 +788,11 @@ public class Tracker.Sparql.Query : Object {
 				accept (SparqlTokenType.DOT);
 			} else {
 				current_subject = parse_construct_var_or_term (var_value_map, out is_null);
+
+				if (is_null) {
+					throw get_error ("'null' not supported for subject");
+				}
+
 				parse_construct_property_list_not_empty (var_value_map);
 				if (!accept (SparqlTokenType.DOT) && current () != SparqlTokenType.GRAPH) {
 					// neither GRAPH nor triples following