From d5a4b60e8f72b76dd4d98b43f77bd9da26c0dc4a Mon Sep 17 00:00:00 2001
From: David Robillard <d@drobilla.net>
Date: Sat, 29 Jan 2011 20:53:08 +0000
Subject: Non-SPARQL version of slv2_plugin_get_value_by_qname.

git-svn-id: http://svn.drobilla.net/lad/trunk/slv2@2857 a436a847-0d15-0410-975c-d299462d15a1
---
 src/plugin.c        | 51 ++++++++++++++++++++++++++++++++++++++++-----------
 src/query.c         |  1 +
 src/slv2_internal.h |  1 +
 src/world.c         | 11 +++++++++++
 4 files changed, 53 insertions(+), 11 deletions(-)

diff --git a/src/plugin.c b/src/plugin.c
index 4282be3..ffd2319 100644
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -119,7 +119,6 @@ slv2_plugin_query_node(SLV2Plugin p, librdf_node* subject, librdf_node* predicat
 		p, subject, predicate, NULL);
 
 	if (librdf_stream_end(results)) {
-		librdf_free_stream(results);
 		return NULL;
 	}
 
@@ -482,20 +481,50 @@ slv2_plugin_get_value(SLV2Plugin p,
 }
 
 
-SLV2Values
-slv2_plugin_get_value_by_qname(SLV2Plugin  p,
-                               const char* predicate)
+static char*
+slv2_qname_expand(SLV2Plugin p, const char* qname)
 {
-	char* query = slv2_strjoin(
-			"SELECT DISTINCT ?value WHERE { \n"
-			"<> ", predicate, " ?value . \n"
-			"}\n", NULL);
+	char* colon = strchr(qname, ':');
+	if (!colon || colon == qname) {
+		SLV2_ERRORF("Invalid QName `%s'\n", qname);
+		return NULL;
+	}
 
-	SLV2Values result = slv2_plugin_query_variable(p, query, 0);
+	const size_t prefix_len = colon - qname;
+	char*        prefix     = malloc(prefix_len + 1);
+	memcpy(prefix, qname, prefix_len);
+	prefix[prefix_len] = '\0';
 
-	free(query);
+	char* namespace = librdf_hash_get(p->world->namespaces, prefix);
+	free(prefix);
+	if (!namespace) {
+		SLV2_ERRORF("QName `%s' has Undefined prefix\n", qname);
+		return NULL;
+	}
 
-	return result;
+	const size_t qname_len     = strlen(qname);
+	const size_t suffix_len    = qname_len - prefix_len - 1;
+	const size_t namespace_len = strlen(namespace);
+	char*        uri           = malloc(namespace_len + suffix_len + 1);
+	memcpy(uri, namespace, namespace_len);
+	memcpy(uri + namespace_len, colon + 1, qname_len - prefix_len - 1);
+	uri[namespace_len + suffix_len] = '\0';
+
+	free(namespace);
+	return uri;
+}
+
+
+SLV2Values
+slv2_plugin_get_value_by_qname(SLV2Plugin  p,
+                               const char* predicate)
+{
+	char*      predicate_uri   = slv2_qname_expand(p, predicate);
+	SLV2Value  predicate_value = slv2_value_new_uri(p->world, predicate_uri);
+	SLV2Values ret             = slv2_plugin_get_value(p, predicate_value);
+	slv2_value_free(predicate_value);
+	free(predicate_uri);
+	return ret;
 }
 
 
diff --git a/src/query.c b/src/query.c
index d190bf2..aebc87b 100644
--- a/src/query.c
+++ b/src/query.c
@@ -211,6 +211,7 @@ slv2_plugin_find_statements(SLV2Plugin   plugin,
                             librdf_node* predicate,
                             librdf_node* object)
 {
+	slv2_plugin_load_if_necessary(plugin);
 	librdf_statement* q = librdf_new_statement_from_nodes(
 		plugin->world->world, subject, predicate, object);
 	librdf_stream* results = librdf_model_find_statements(plugin->rdf, q);
diff --git a/src/slv2_internal.h b/src/slv2_internal.h
index 93ef6af..9ba8606 100644
--- a/src/slv2_internal.h
+++ b/src/slv2_internal.h
@@ -150,6 +150,7 @@ struct _SLV2World {
 	librdf_storage*   storage;
 	librdf_model*     model;
 	librdf_parser*    parser;
+	librdf_hash*      namespaces;
 	SLV2PluginClass   lv2_plugin_class;
 	SLV2PluginClasses plugin_classes;
 	SLV2Plugins       plugins;
diff --git a/src/world.c b/src/world.c
index a4e21ae..893d39c 100644
--- a/src/world.c
+++ b/src/world.c
@@ -79,6 +79,15 @@ slv2_world_new_internal(SLV2World world)
 	world->lv2_plugin_class = slv2_plugin_class_new(world, NULL,
 			librdf_node_get_uri(world->lv2_plugin_node), "Plugin");
 
+	world->namespaces = librdf_new_hash_from_string(
+		world->world, NULL,
+		"rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#',"
+		"rdfs='http://www.w3.org/2000/01/rdf-schema#',"
+		"doap='http://usefulinc.com/ns/doap#',"
+		"foaf='http://xmlns.com/foaf/0.1/',"
+		"lv2='http://lv2plug.in/ns/lv2core#',"
+		"lv2ev='http://lv2plug.in/ns/ext/event#'");
+
 	return world;
 
 fail:
@@ -182,6 +191,8 @@ slv2_world_free(SLV2World world)
 	librdf_free_storage(world->storage);
 	world->storage = NULL;
 
+	librdf_free_hash(world->namespaces);
+
 	if (world->local_world)
 		librdf_free_world(world->world);
 
-- 
cgit v1.2.1