1 files changed, 123 insertions, 0 deletions
diff --git a/src/query.c b/src/query.c
new file mode 100644
index 0000000..2030735
--- /dev/null
+++ b/src/query.c
@@ -0,0 +1,123 @@
+/* LibSLV2
+ * Copyright (C) 2006 Dave Robillard <drobilla@connect.carleton.ca>
+ *  
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <util.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <slv2/plugin.h>
+#include <slv2/query.h>
+
+
+unsigned char*
+slv2_query_header(const SLV2Plugin* p)
+{
+	const unsigned char* plugin_uri = slv2_plugin_get_uri(p);
+	const unsigned char* data_file_url = slv2_plugin_get_data_url(p);
+
+	unsigned char* query_string = ustrjoin(U(
+		  "PREFIX rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> \n"
+		  "PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#> \n"
+		  "PREFIX doap:   <http://usefulinc.com/ns/doap#> \n"
+		  "PREFIX lv2:    <http://lv2plug.in/ontology#> \n"
+		  "PREFIX plugin: <"), plugin_uri, U("> \n"),
+		U("PREFIX data:   <"), data_file_url, U("> \n\n"), 0);
+
+	return query_string;
+}
+
+
+unsigned char*
+slv2_query_lang_filter(const uchar* variable)
+{
+	uchar* result = NULL;
+	uchar* const lang = (uchar*)getenv("LANG");
+	if (lang) {
+		// FILTER( LANG(?value) = "en" || LANG(?value) = "" )
+		result = ustrjoin(
+			//U("FILTER (lang(?value) = \""), lang, U("\")\n"), 0);
+			U("FILTER( lang(?value) = \""), lang, 
+			U("\" || lang(?value) = \"\" )\n"), 0);
+	}
+
+	return result;
+}
+
+
+rasqal_query_results*
+slv2_plugin_run_query(const SLV2Plugin* p,
+                      const uchar*        first, ...)
+{
+	va_list args_list;
+	va_start(args_list, first);
+	va_list args_copy;
+	va_copy(args_copy, args_list);
+
+	/* FIXME:  Too much unecessary allocation */
+	uchar* header = slv2_query_header(p);
+	uchar* args_str = vstrjoin(first, args_copy);
+	uchar* query_str = ustrjoin(header, args_str, 0);
+	
+	assert(p);
+	assert(query_str);
+
+	rasqal_query *rq = rasqal_new_query("sparql", NULL);
+
+	//printf("Query: \n%s\n\n", query_str);
+
+	rasqal_query_prepare(rq, query_str, NULL);
+	rasqal_query_results* results = rasqal_query_execute(rq);
+	
+	rasqal_free_query(rq);
+	
+	free(query_str);
+	free(args_str);
+	free(header);
+	
+	return results;
+}
+
+
+SLV2Property
+slv2_query_get_results(rasqal_query_results* results)
+{
+	struct _Property* result = NULL;
+	
+	if (rasqal_query_results_get_count(results) > 0) {
+		result = malloc(sizeof(struct _Property));
+		result->num_values = 0;
+		result->values = NULL;
+	}
+	
+	while (!rasqal_query_results_finished(results)) {
+		
+		rasqal_literal* literal =
+			rasqal_query_results_get_binding_value_by_name(results, U("value"));
+		assert(literal != NULL);
+		
+		// Add value on to the array.  Yes, this is disgusting.
+		result->num_values++;
+		// FIXME LEAK:
+		result->values = realloc(result->values, result->num_values * sizeof(char*));
+		result->values[result->num_values-1] = ustrdup(rasqal_literal_as_string(literal));
+		
+		rasqal_query_results_next(results);
+	}
+
+	return result;
+}
+