Start using a class for management and (perhaps later) caching of dormant media nodes

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@721 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/media/DormantNodeManager.h

@@ -0,0 +1,59 @@
+/* 
+ * Copyright 2002, Marcus Overhagen. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+
+#ifndef _DORMANT_NODE_MANAGER_H
+#define _DORMANT_NODE_MANAGER_H
+
+#include "TMap.h"
+
+namespace BPrivate {
+namespace media {
+
+class DormantNodeManager
+{
+public:
+	DormantNodeManager();
+	~DormantNodeManager();
+
+//	InstantiateDormantNode(const dormant_node_info & in_info, bool global, media_node * out_node);
+
+	// Be careful, GetAddon and PutAddon must be balanced.
+	BMediaAddOn *GetAddon(media_addon_id id);
+	void PutAddon(media_addon_id id);
+
+	// For use by media_addon_server only
+	media_addon_id RegisterAddon(const char *path);
+	void UnregisterAddon(media_addon_id id);
+
+private:
+	struct loaded_addon_info
+	{
+		BMediaAddOn *addon;
+		image_id image;
+		int32 usecount;
+	};
+
+	// returns the addon or NULL if it needs to be loaded
+	BMediaAddOn *TryGetAddon(media_addon_id id);
+	
+	// manage loading and unloading add-ons from images
+	status_t LoadAddon(BMediaAddOn **newaddon, image_id *newimage, const char *path, media_addon_id id);
+	void UnloadAddon(BMediaAddOn *addon, image_id image);
+
+	// query the server for the path
+	status_t FindAddonPath(BPath *path, media_addon_id id);
+	
+private:
+
+	Map<media_addon_id,loaded_addon_info> *fAddonmap;
+	BLocker *fLock;
+};
+
+}; // namespace media
+}; // namespace BPrivate
+
+extern BPrivate::media::DormantNodeManager *_DormantNodeManager;
+
+#endif /* _DORMANT_NODE_MANAGER_H */