Const-correct node API.

git-svn-id: http://svn.drobilla.net/sord/trunk@98 3d64ff67-21c5-427c-a301-fe4f08042e5a

4 files changed, 34 insertions, 31 deletions

diff --git a/sord/sord.h b/sord/sord.h
index 587456b..8d31085 100644
--- a/sord/sord.h
+++ b/sord/sord.h
@@ -91,7 +91,7 @@ typedef struct SordNodeImpl SordNode;
 
    Nodes are ordered (S P O G).  The ID of the default graph is 0.
 */
-typedef SordNode* SordQuad[4];
+typedef const SordNode* SordQuad[4];
 
 /**
    Index into a SordQuad.
@@ -220,7 +220,7 @@ sord_new_literal_counted(SordWorld*     world,
 */
 SORD_API
 SordNode*
-sord_node_copy(SordNode* node);
+sord_node_copy(const SordNode* node);
 
 /**
    Free a node (i.e. drop a reference).
diff --git a/sord/sordmm.hpp b/sord/sordmm.hpp
index 294f38f..dc80cb3 100644
--- a/sord/sordmm.hpp
+++ b/sord/sordmm.hpp
@@ -149,7 +149,7 @@ public:
 
 	inline Node(World& world, Type t, const std::string& s);
 	inline Node(World& world);
-	inline Node(World& world, SordNode* node);
+	inline Node(World& world, const SordNode* node);
 	inline Node(const Node& other);
 	inline ~Node();
 
@@ -269,7 +269,7 @@ Node::Node(World& world)
 }
 
 inline
-Node::Node(World& world, SordNode* node)
+Node::Node(World& world, const SordNode* node)
 	: _world(&world)
 {
 	_c_obj = node ? sord_node_copy(node) : NULL;
diff --git a/src/sord.c b/src/sord.c
index ff449ee..75e9287 100644
--- a/src/sord.c
+++ b/src/sord.c
@@ -314,7 +314,7 @@ sord_iter_seek_match(SordIter* iter)
 	for (iter->end = true;
 	     !g_sequence_iter_is_end(iter->cur);
 	     sord_iter_forward(iter)) {
-		SordNode** const key = (SordNode**)g_sequence_get(iter->cur);
+		const SordNode** const key = (const SordNode**)g_sequence_get(iter->cur);
 		if (sord_quad_match_inline(key, iter->pat))
 			return (iter->end = false);
 	}
@@ -332,7 +332,7 @@ sord_iter_seek_match_range(SordIter* iter)
 		return true;
 
 	do {
-		SordNode** key = (SordNode**)g_sequence_get(iter->cur);
+		const SordNode** key = (const SordNode**)g_sequence_get(iter->cur);
 
 		if (sord_quad_match_inline(key, iter->pat))
 			return false; // Found match
@@ -371,7 +371,7 @@ sord_iter_new(const SordModel* sord, GSequenceIter* cur, const SordQuad pat,
 	case SINGLE:
 	case RANGE:
 		assert(
-			sord_quad_match_inline((SordNode**)g_sequence_get(iter->cur),
+			sord_quad_match_inline((const SordNode**)g_sequence_get(iter->cur),
 			                       iter->pat));
 		break;
 	case FILTER_RANGE:
@@ -588,18 +588,18 @@ sord_new(SordWorld* world, unsigned indices, bool graphs)
 }
 
 static void
-sord_add_quad_ref(SordModel* sord, SordNode* node)
+sord_add_quad_ref(SordModel* sord, const SordNode* node)
 {
 	if (node) {
 		assert(node->refs > 0);
-		++node->refs;
+		++((SordNode*)node)->refs;
 	}
 }
 
 static void
-sord_drop_quad_ref(SordModel* sord, SordNode* node)
+sord_drop_quad_ref(SordModel* sord, const SordNode* node)
 {
-	sord_node_free(sord_get_world(sord), node);
+	sord_node_free(sord_get_world(sord), (SordNode*)node);
 }
 
 void
@@ -731,10 +731,10 @@ sord_find(SordModel* sord, const SordQuad pat)
 	// It's easiest to think about this algorithm in terms of (S P O) ordering,
 	// assuming (A B C) == (S P O).  For other orderings this is not actually
 	// the case, but it works the same way.
-	SordNode* a = pat[ordering[0]]; // Most Significant Node (MSN)
-	SordNode* b = pat[ordering[1]]; // ...
-	SordNode* c = pat[ordering[2]]; // ...
-	SordNode* d = pat[ordering[3]]; // Least Significant Node (LSN)
+	const SordNode* a = pat[ordering[0]]; // Most Significant Node (MSN)
+	const SordNode* b = pat[ordering[1]]; // ...
+	const SordNode* c = pat[ordering[2]]; // ...
+	const SordNode* d = pat[ordering[3]]; // Least Significant Node (LSN)
 
 	if (a && b && c && d)
 		mode = SINGLE; // No duplicate quads (Sord is a set)
@@ -746,7 +746,7 @@ sord_find(SordModel* sord, const SordQuad pat)
 		SORD_FIND_LOG("No match found\n");
 		return NULL;
 	}
-	SordNode** const key = (SordNode**)g_sequence_get(cur);
+	const SordNode** const key = (const SordNode**)g_sequence_get(cur);
 	if (!key || ( (mode == RANGE || mode == SINGLE)
 	              && !sord_quad_match_inline(search_key, key) )) {
 		SORD_FIND_LOG("No match found\n");
@@ -957,12 +957,13 @@ sord_node_free(SordWorld* world, SordNode* node)
 }
 
 SordNode*
-sord_node_copy(SordNode* node)
+sord_node_copy(const SordNode* node)
 {
-	if (node) {
-		++node->refs;
+	SordNode* copy = (SordNode*)node;
+	if (copy) {
+		++copy->refs;
 	}
-	return node;
+	return copy;
 }
 
 static inline bool
diff --git a/src/syntax.c b/src/syntax.c
index daeec69..a0198c3 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -151,26 +151,28 @@ event_statement(void*           handle,
 {
 	ReadState* const state = (ReadState*)handle;
 
-	SordQuad tup;
-	tup[0] = sord_node_from_serd_node(state, subject, NULL, NULL);
-	tup[1] = sord_node_from_serd_node(state, predicate, NULL, NULL);
-	tup[2] = sord_node_from_serd_node(state, object,
-	                                  object_datatype, object_lang);
+	SordNode* s = sord_node_from_serd_node(state, subject, NULL, NULL);
+	SordNode* p = sord_node_from_serd_node(state, predicate, NULL, NULL);
+	SordNode* o = sord_node_from_serd_node(state, object,
+	                                       object_datatype, object_lang);
 
+	SordNode* g = NULL;
 	if (state->graph_uri_node) {
 		assert(graph->type == SERD_NOTHING);
-		tup[3] = sord_node_copy(state->graph_uri_node);
+		g = sord_node_copy(state->graph_uri_node);
 	} else {
-		tup[3] = (graph && graph->buf)
+		g = (graph && graph->buf)
 			? sord_node_from_serd_node(state, graph, NULL, NULL)
 			: NULL;
 	}
 
+	const SordQuad tup = { s, p, o, g };
 	sord_add(state->sord, tup);
-	sord_node_free(state->world, tup[0]);
-	sord_node_free(state->world, tup[1]);
-	sord_node_free(state->world, tup[2]);
-	sord_node_free(state->world, tup[3]);
+
+	sord_node_free(state->world, s);
+	sord_node_free(state->world, p);
+	sord_node_free(state->world, o);
+	sord_node_free(state->world, g);
 
 	return true;
 }