Improve performances of symbol list updating

Rather than walking the whole tree for each tag to find a possibly
corresponding row, use a hash table as cache.
This is a very significant improvement on large files with many tags,
reducing for example to about 170ms an update that took more than 18s
before.

Also fix merging of tags with same name and scope (probably unlikely to
exist in real-world files, but the tagmanager extract them correctly
and they used to display correctly too).


git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@5567 ea778897-0a13-0410-b9d1-a72fbfd435f5

src/symbols.c

@@ -1161,30 +1161,89 @@ static GdkPixbuf *get_child_icon(GtkTreeStore *tree_store, GtkTreeIter *parent)
 }
 
 
-static gboolean find_iter(GtkTreeStore *store, GtkTreeIter *iter, const TMTag *tag)
+static gboolean tag_equal(gconstpointer v1, gconstpointer v2)
 {
-	GtkTreeModel *model = GTK_TREE_MODEL(store);
-	gboolean found = FALSE;
+	const TMTag *t1 = v1;
+	const TMTag *t2 = v2;
 
-	if (!gtk_tree_model_get_iter_first(model, iter))
-		return FALSE;
-	do
-	{
-		TMTag *candidate;
-
-		gtk_tree_model_get(model, iter, SYMBOLS_COLUMN_TAG, &candidate, -1);
-		found = (candidate && candidate->type == tag->type &&
-				 utils_str_equal(candidate->name, tag->name) &&
-				 utils_str_equal(candidate->atts.entry.scope, tag->atts.entry.scope));
-		tm_tag_unref(candidate);
-	}
-	while (!found && next_iter(model, iter));
-
-	return found;
+	return (t1->type == t2->type && strcmp(t1->name, t2->name) == 0 &&
+			utils_str_equal(t1->atts.entry.scope, t2->atts.entry.scope));
 }
 
 
-static void add_tree_tag(GeanyDocument *doc, const TMTag *tag, GHashTable *parent_hash)
+/* inspired from g_str_hash() */
+static guint tag_hash(gconstpointer v)
+{
+	const TMTag *tag = v;
+	const signed char *p;
+	guint32 h = 5381;
+
+	h = (h << 5) + h + tag->type;
+	for (p = tag->name; *p != '\0'; p++)
+		h = (h << 5) + h + *p;
+	if (tag->atts.entry.scope)
+	{
+		for (p = tag->atts.entry.scope; *p != '\0'; p++)
+			h = (h << 5) + h + *p;
+	}
+
+	return h;
+}
+
+
+static GHashTable *build_iter_table(GtkTreeStore *store)
+{
+	GtkTreeModel *model = GTK_TREE_MODEL(store);
+	GHashTable *table;
+	GtkTreeIter iter;
+
+	table = g_hash_table_new_full(tag_hash, tag_equal,
+			(GDestroyNotify)tm_tag_unref, (GDestroyNotify)gtk_tree_path_free);
+
+	if (!gtk_tree_model_get_iter_first(model, &iter))
+		return table;
+	do
+	{
+		TMTag *tag;
+
+		gtk_tree_model_get(model, &iter, SYMBOLS_COLUMN_TAG, &tag, -1);
+		if (tag)
+			g_hash_table_insert(table, tag, gtk_tree_model_get_path(model, &iter));
+	}
+	while (next_iter(model, &iter));
+
+	return table;
+}
+
+
+static gboolean find_iter(GtkTreeStore *store, GHashTable *iter_hash, const TMTag *tag,
+		GtkTreeIter *iter)
+{
+	GtkTreePath *path;
+
+	path = g_hash_table_lookup(iter_hash, tag);
+	if (path)
+	{
+		GtkTreeIter tmp;
+		gboolean valid;
+
+		if (!gtk_tree_model_get_iter(GTK_TREE_MODEL(store), &tmp, path))
+			return FALSE;
+		gtk_tree_model_get(GTK_TREE_MODEL(store), &tmp, SYMBOLS_COLUMN_VALID, &valid, -1);
+		/* if the row is valid it has already been updated, so it's simply a duplicate */
+		if (!valid)
+		{
+			*iter = tmp;
+			return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
+
+static void add_tree_tag(GeanyDocument *doc, const TMTag *tag, GHashTable *parent_hash,
+		GHashTable *iter_hash)
 {
 	filetype_id ft_id = doc->file_type->id;
 	GtkTreeStore *tree_store = doc->priv->tag_store;
@@ -1226,7 +1285,7 @@ static void add_tree_tag(GeanyDocument *doc, const TMTag *tag, GHashTable *paren
 			child = new_iter;
 		}
 
-		if (!find_iter(tree_store, child, tag))
+		if (!find_iter(tree_store, iter_hash, tag, child))
 		{
 			gboolean expand = FALSE;
 
@@ -1271,9 +1330,11 @@ static void add_tree_tags(GeanyDocument *doc, const GList *tags)
 {
 	const GList *item;
 	GHashTable *parent_hash;
+	GHashTable *iter_hash;
 
 	/* Create a hash table "parent_tag_name":(GtkTreeIter*) */
 	parent_hash = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, g_free);
+	iter_hash = build_iter_table(doc->priv->tag_store);
 
 	/* find and store all parent names in the hash table */
 	for (item = tags; item; item = g_list_next(item))
@@ -1288,8 +1349,9 @@ static void add_tree_tags(GeanyDocument *doc, const GList *tags)
 	{
 		const TMTag *tag = item->data;
 
-		add_tree_tag(doc, tag, parent_hash);
+		add_tree_tag(doc, tag, parent_hash, iter_hash);
 	}
+	g_hash_table_destroy(iter_hash);
 	g_hash_table_destroy(parent_hash);
 }