Saner (internal) query API, though still needs work.

Preliminary (untested) support for host features/extensions/whatever.
Documentation fixes and minor cleanups.


git-svn-id: http://svn.drobilla.net/lad/libslv2@113 a436a847-0d15-0410-975c-d299462d15a1

1 files changed, 93 insertions, 34 deletions

diff --git a/src/query.c b/src/query.c
index 56903ac..177d06e 100644
--- a/src/query.c
+++ b/src/query.c
@@ -58,9 +58,55 @@ slv2_query_lang_filter(const char* variable)
 }
 
 
-rasqal_query_results*
-slv2_plugin_run_query(const SLV2Plugin* p,
-                      const char*       query)
+SLV2Property
+slv2_query_get_variable_bindings(rasqal_query_results* results, const char* var_name)
+{
+	struct _Property* result = NULL;
+
+    if (rasqal_query_results_get_bindings_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, (const unsigned char*)var_name);
+        assert(literal != NULL);
+
+        // Add value on to the array, reallocing all the way.
+		// Yes, this is disgusting.  Roughly as disgusting as the rasqal query
+		// results API.  coincidentally.
+        result->num_values++;
+        result->values = realloc(result->values, result->num_values * sizeof(char*));
+        result->values[result->num_values-1] = strdup((const char*)rasqal_literal_as_string(literal));
+
+        rasqal_query_results_next(results);
+    }
+
+    return result;
+}
+
+
+size_t
+slv2_query_count_variable_bindings(rasqal_query_results* results)
+{
+	size_t count = 0;
+
+    while (!rasqal_query_results_finished(results)) {
+		++count;
+        rasqal_query_results_next(results);
+    }
+
+    return count;
+}
+
+
+SLV2Property
+slv2_query_get_results(const SLV2Plugin* p,
+                       const char*       query,
+                       const char*       var_name)
 {
 	char* header    = slv2_query_header(p);
 	char* query_str = strjoin(header, query, NULL);
@@ -68,21 +114,63 @@ slv2_plugin_run_query(const SLV2Plugin* p,
 	assert(p);
 	assert(query_str);
 
+	rasqal_init();
+
 	rasqal_query *rq = rasqal_new_query("sparql", NULL);
 
 	//printf("Query: \n%s\n\n", query_str);
 
 	rasqal_query_prepare(rq, (unsigned char*)query_str, NULL);
 	rasqal_query_results* results = rasqal_query_execute(rq);
+	assert(results);
 	
+	SLV2Property ret = slv2_query_get_variable_bindings(results, var_name);
+	rasqal_free_query_results(results);
 	rasqal_free_query(rq);
 	
+	rasqal_finish();
+	
 	free(query_str);
 	free(header);
+
+	return ret;
+}
+
+
+size_t
+slv2_query_count_results(const SLV2Plugin* p,
+                         const char*       query)
+{
+	char* header    = slv2_query_header(p);
+	char* query_str = strjoin(header, query, NULL);
+
+	assert(p);
+	assert(query_str);
+
+	rasqal_init();
+
+	rasqal_query *rq = rasqal_new_query("sparql", NULL);
+
+	//printf("Query: \n%s\n\n", query_str);
+
+	rasqal_query_prepare(rq, (unsigned char*)query_str, NULL);
+	rasqal_query_results* results = rasqal_query_execute(rq);
+	assert(results);
 	
-	return results;
+	size_t count = slv2_query_count_variable_bindings(results);
+	
+	rasqal_free_query_results(results);
+	rasqal_free_query(rq);
+	
+	rasqal_finish();
+	
+	free(query_str);
+	free(header);
+
+	return count;
 }
 
+/*
 size_t
 slv2_query_get_num_results(rasqal_query_results* results, const char* var_name)
 {
@@ -97,36 +185,7 @@ slv2_query_get_num_results(rasqal_query_results* results, const char* var_name)
 
 	return result;
 }
-
-SLV2Property
-slv2_query_get_results(rasqal_query_results* results, const char* var_name)
-{
-	struct _Property* result = NULL;
-
-    if (rasqal_query_results_get_bindings_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, (const unsigned char*)var_name);
-        assert(literal != NULL);
-
-        // Add value on to the array, reallocing all the way.
-		// Yes, this is disgusting.  Roughly as disgusting as the rasqal query
-		// results API.  coincidentally.
-        result->num_values++;
-        result->values = realloc(result->values, result->num_values * sizeof(char*));
-        result->values[result->num_values-1] = strdup((const char*)rasqal_literal_as_string(literal));
-
-        rasqal_query_results_next(results);
-    }
-
-    return result;
-}
+*/
 
 void
 slv2_property_free(struct _Property* prop)