Add slv2_port_get_value.

git-svn-id: http://svn.drobilla.net/lad/trunk/slv2@1533 a436a847-0d15-0410-975c-d299462d15a1

3 files changed, 55 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 26de243..e870051 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+slv2 (9999) unstable; urgency=low
+
+  * NOT YET RELEASED
+  * Add slv2_port_get_value (analogous to slv2_plugin_get_value).
+ 
+ -- Dave Robillard <dave@drobilla.net>  Sun, 01 Jan 9999 00:00:00 -0400
+
 slv2 (0.6.0) unstable; urgency=low
 
   * Rework API to reduce dependence of SLV2 on specific LV2 features
diff --git a/slv2/port.h b/slv2/port.h
index a55a1a8..1497884 100644
--- a/slv2/port.h
+++ b/slv2/port.h
@@ -38,6 +38,16 @@ extern "C" {
  * Time = Query
  */
 SLV2Values
+slv2_port_get_value(SLV2Plugin plugin,
+                    SLV2Port   port,
+                    SLV2Value  predicate);
+
+
+/** Port analog of slv2_plugin_get_value_by_qname.
+ *
+ * Time = Query
+ */
+SLV2Values
 slv2_port_get_value_by_qname(SLV2Plugin  plugin,
                              SLV2Port    port,
                              const char* property_uri);
diff --git a/src/port.c b/src/port.c
index 9166fcc..cffbd0e 100644
--- a/src/port.c
+++ b/src/port.c
@@ -150,6 +150,44 @@ slv2_port_get_value_by_qname(SLV2Plugin  p,
 }
 
 
+SLV2Values
+slv2_port_get_value(SLV2Plugin p,
+                    SLV2Port   port,
+                    SLV2Value  predicate)
+{
+	char* query = NULL;
+	
+	/* Hack around broken RASQAL, full URI predicates don't work :/ */
+
+	if (predicate->type == SLV2_VALUE_URI) {
+		query = slv2_strjoin(
+			"PREFIX slv2predicate: <", slv2_value_as_string(predicate), ">",
+			"SELECT DISTINCT ?value WHERE { \n"
+			"<", slv2_value_as_uri(p->plugin_uri), "> lv2:port ?port .\n"
+			"?port lv2:symbol \"", slv2_value_as_string(port->symbol), "\";\n\t",
+				" slv2predicate: ?value .\n"
+			"}\n", NULL);
+	} else if (predicate->type == SLV2_VALUE_QNAME) {
+    	query = slv2_strjoin(
+			"SELECT DISTINCT ?value WHERE { \n"
+			"<", slv2_value_as_uri(p->plugin_uri), "> lv2:port ?port .\n"
+			"?port lv2:symbol \"", slv2_value_as_string(port->symbol), "\";\n\t",
+				slv2_value_as_string(predicate), " ?value .\n"
+			"}\n", NULL);
+	} else {
+		fprintf(stderr, "slv2_port_get_value error: "
+				"predicate is not a URI or QNAME\n");
+		return NULL;
+	}
+
+	SLV2Values result = slv2_plugin_query_variable(p, query, 0);
+	
+	free(query);
+
+	return result;
+}
+
+
 SLV2Value
 slv2_port_get_symbol(SLV2Plugin p,
                      SLV2Port   port)