Add lilv_world_ask() for easily checking if a statement exists.

Add lilv_world_get() and lilv_port_get() for easily getting one value.


git-svn-id: http://svn.drobilla.net/lad/trunk/lilv@5053 a436a847-0d15-0410-975c-d299462d15a1

7 files changed, 74 insertions, 4 deletions

diff --git a/NEWS b/NEWS
index 2da319e..8b2446b 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,7 @@
-lilv (0.15.0) unstable;
+lilv (0.15.1) unstable;
 
-  * Add lilv_world_ask() for simply checking if a statement exists
+  * Add lilv_world_ask() for easily checking if a statement exists
+  * Add lilv_world_get() and lilv_port_get() for easily getting one value
   * Add lilv_nodes_merge()
   * Make lilv_plugin_get_port_by_designation() return a const pointer
   * Require a URI for lilv_state_to_string() and fail gracefully otherwise
@@ -17,7 +18,7 @@ lilv (0.15.0) unstable;
   * lilvmm.hpp: Add several missing methods
   * Update to waf 1.7.8 and autowaf r90 (install docs to versioned directory)
 
- -- David Robillard <d@drobilla.net>  Sat, 02 Feb 2013 15:10:18 -0500
+ -- David Robillard <d@drobilla.net>  Sun, 10 Feb 2013 01:10:12 -0500
 
 lilv (0.14.4) stable;
 
diff --git a/lilv/lilv.h b/lilv/lilv.h
index 6719e67..f2dd17a 100644
--- a/lilv/lilv.h
+++ b/lilv/lilv.h
@@ -650,6 +650,21 @@ lilv_world_find_nodes(LilvWorld*      world,
                       const LilvNode* object);
 
 /**
+   Find a single node that matches a pattern.
+   Exactly one of @p subject, @p predicate, @p object must be NULL.
+   This function is equivalent to
+   lilv_nodes_get_first(lilv_world_find_nodes(...)) but simplifies the common
+   case of only wanting a single value.
+   @return the first matching node, or NULL if no matches are found.
+*/
+LILV_API
+LilvNode*
+lilv_world_get(LilvWorld*      world,
+               const LilvNode* subject,
+               const LilvNode* predicate,
+               const LilvNode* object);
+
+/**
    Return true iff a statement matching a certain pattern exists.
 
    This is useful for checking if particular statement exists without having to
@@ -1058,6 +1073,19 @@ lilv_port_get_value(const LilvPlugin* plugin,
                     const LilvNode*   predicate);
 
 /**
+   Get a single property value of a port.
+
+   This is equivalent to lilv_nodes_get_first(lilv_port_get_value(...)) but is
+   simpler to use in the common case of only caring about one value.  The
+   caller is responsible for freeing the returned node.
+*/
+LILV_API
+LilvNode*
+lilv_port_get(const LilvPlugin* plugin,
+              const LilvPort*   port,
+              const LilvNode*   predicate);
+
+/**
    Return the LV2 port properties of a port.
 */
 LILV_API
diff --git a/src/node.c b/src/node.c
index 495bb49..7b22873 100644
--- a/src/node.c
+++ b/src/node.c
@@ -92,6 +92,10 @@ lilv_node_new(LilvWorld* world, LilvNodeType type, const char* str)
 LilvNode*
 lilv_node_new_from_node(LilvWorld* world, const SordNode* node)
 {
+	if (!node) {
+		return NULL;
+	}
+
 	LilvNode*    result       = NULL;
 	SordNode*    datatype_uri = NULL;
 	LilvNodeType type         = LILV_VALUE_STRING;
diff --git a/src/port.c b/src/port.c
index 00896df..48d87dd 100644
--- a/src/port.c
+++ b/src/port.c
@@ -127,6 +127,21 @@ lilv_port_get_value(const LilvPlugin* p,
 }
 
 LILV_API
+LilvNode*
+lilv_port_get(const LilvPlugin* p,
+              const LilvPort*   port,
+              const LilvNode*   predicate)
+{
+	LilvNodes* values = lilv_port_get_value(p, port, predicate);
+
+	LilvNode* value = lilv_node_duplicate(
+		values ? lilv_nodes_get_first(values) : NULL);
+
+	lilv_nodes_free(values);
+	return value;
+}
+
+LILV_API
 uint32_t
 lilv_port_get_index(const LilvPlugin* p,
                     const LilvPort*   port)
diff --git a/src/world.c b/src/world.c
index a3f59ed..147690b 100644
--- a/src/world.c
+++ b/src/world.c
@@ -201,6 +201,22 @@ lilv_world_find_nodes(LilvWorld*      world,
 		object ? object->node : NULL);
 }
 
+LILV_API
+LilvNode*
+lilv_world_get(LilvWorld*      world,
+               const LilvNode* subject,
+               const LilvNode* predicate,
+               const LilvNode* object)
+{
+	return lilv_node_new_from_node(
+		world,
+		sord_get(world->model,
+		         subject ? subject->node : NULL,
+		         predicate ? predicate->node : NULL,
+		         object ? object->node : NULL,
+		         NULL));
+}
+
 SordIter*
 lilv_world_query_internal(LilvWorld*      world,
                           const SordNode* subject,
diff --git a/test/lilv_test.c b/test/lilv_test.c
index 0033885..0a505b0 100644
--- a/test/lilv_test.c
+++ b/test/lilv_test.c
@@ -711,6 +711,8 @@ test_plugin(void)
 	TEST_ASSERT(thing_name);
 	TEST_ASSERT(lilv_node_is_string(thing_name));
 	TEST_ASSERT(!strcmp(lilv_node_as_string(thing_name), "Something else"));
+	LilvNode* thing_name2 = lilv_world_get(world, thing_uri, name_p, NULL);
+	TEST_ASSERT(lilv_node_equals(thing_name, thing_name2));
 
 	LilvUIs* uis = lilv_plugin_get_uis(plug);
 	TEST_ASSERT(lilv_uis_size(uis) == 0);
@@ -729,6 +731,7 @@ test_plugin(void)
 
 	lilv_nodes_free(thing_names);
 	lilv_node_free(thing_uri);
+	lilv_node_free(thing_name2);
 	lilv_node_free(name_p);
 	lilv_node_free(control_class);
 	lilv_node_free(audio_class);
@@ -849,6 +852,9 @@ test_port(void)
 	LilvNodes* comments     = lilv_port_get_value(plug, p, rdfs_comment);
 	TEST_ASSERT(!strcmp(lilv_node_as_string(lilv_nodes_get_first(comments)),
 	                    "comment"));
+	LilvNode* comment = lilv_port_get(plug, p, rdfs_comment);
+	TEST_ASSERT(!strcmp(lilv_node_as_string(comment), "comment"));
+	lilv_node_free(comment);
 	lilv_nodes_free(comments);
 
 	setenv("LANG", "fr", 1);
diff --git a/wscript b/wscript
index e666f43..4df9917 100644
--- a/wscript
+++ b/wscript
@@ -9,7 +9,7 @@ import waflib.extras.autowaf as autowaf
 # major increment <=> incompatible changes
 # minor increment <=> compatible changes (additions)
 # micro increment <=> no interface changes
-LILV_VERSION       = '0.15.0'
+LILV_VERSION       = '0.15.1'
 LILV_MAJOR_VERSION = '0'
 
 # Mandatory waf variables