X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Fgraphics%2FGraphicsCache.h;h=0fd1dd0102a1945eb990c32140f79d7a4c2a2018;hb=c6f262a5b74e7bf595efd6a02ca26a2900e5e6eb;hp=d64df5f5d321193930dcc2b9c1fb2ab5433721d7;hpb=7110b8eda4ab2dc3e87c53c89225caaff972f9eb;p=lyx.git

diff --git a/src/graphics/GraphicsCache.h b/src/graphics/GraphicsCache.h
index d64df5f5d3..0fd1dd0102 100644
--- a/src/graphics/GraphicsCache.h
+++ b/src/graphics/GraphicsCache.h
@@ -1,54 +1,92 @@
 // -*- C++ -*-
-/* This file is part of
- * =================================================
- * 
- *          LyX, The Document Processor
- *          Copyright 1995 Matthias Ettrich.
- *          Copyright 1995-2000 The LyX Team.
+/**
+ * \file GraphicsCache.h
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
  *
- *          This file Copyright 2000 Baruch Even
- * ================================================= */
+ * \author Baruch Even
+ * \author Angus Leeming
+ *
+ * Full author contact details are available in file CREDITS.
+ *
+ * lyx::graphics::Cache is the manager of the image cache.
+ * It is responsible for creating the lyx::graphics::CacheItem's
+ * and maintaining them.
+ *
+ * lyx::graphics::Cache is a singleton class. It is possible to have only one
+ * instance of it at any moment.
+ */
 
 #ifndef GRAPHICSCACHE_H
 #define GRAPHICSCACHE_H
 
-#ifdef __GNUG__
-#pragma interface
-#endif
+#include <memory>
+#include <string>
+#include <vector>
 
-#include <map>
 
-#include "LString.h"
-#include "GraphicsCacheItem.h"
+namespace lyx {
 
-/** GraphicsCache is the manager of the image cache, it is responsible to
- * create the GraphicsCacheItem's and maintain them.
- *
- * GraphicsCache is a singleton class, there should be only one instance of
- * it at any moment.
- */
-class GraphicsCache {
+namespace support { class FileName; }
+
+namespace graphics {
+
+class CacheItem;
+
+class Cache {
 public:
-    /// Get the instance of the class.
-    static GraphicsCache * getInstance();
 
-    /// Add a file to the cache.
-    GraphicsCacheItem * addFile(string const & filename);
+	/// This is a singleton class. Get the instance.
+	static Cache & get();
 
-private:
-    /// Remove a cache item if it's count has gone to zero.
-    void removeFile(string const & filename);
-    
-    /// Private c-tor so we can control how many objects are instantiated.
-    GraphicsCache() {}
+	/** Which graphics formats can be loaded directly by the image loader.
+	 *  Other formats can be loaded if a converter to a loadable format
+	 *  can be defined.
+	 */
+	std::vector<std::string> const & loadableFormats() const;
+
+	/// Add a graphics file to the cache.
+	void add(support::FileName const & file, support::FileName const & doc_file) const;
+
+	/// Remove a file from the cache.
+	void remove(support::FileName const & file) const;
+
+	/// Returns \c true if the file is in the cache.
+	bool inCache(support::FileName const & file) const;
 
-    /// Private d-tor so that no-one will destroy us.
-    ~GraphicsCache();
+	/** Get the cache item associated with file.
+	 *  Returns an empty container if there is no such item.
+	 *
+	 *  IMPORTANT: whatever uses an image must make a local copy of this
+	 *  ItemPtr. The shared_ptr<>::use_count() function is
+	 *  used to ascertain whether or not to remove the item from the cache
+	 *  when remove(file) is called.
+	 *
+	 *  You have been warned!
+	 */
+	typedef std::shared_ptr<CacheItem> ItemPtr;
+	///
+	ItemPtr const item(support::FileName const & file) const;
 
-    /// Holder of the single instance of the class.
-    static GraphicsCache * singleton;
+private:
+	/// noncopyable
+	Cache(Cache const &);
+	void operator=(Cache const &);
+
+	/** Make the c-tor, d-tor private so we can control how many objects
+	 *  are instantiated.
+	 */
+	Cache();
+	///
+	~Cache();
 
-    typedef std::map<string, GraphicsCacheItem *> CacheType;
-    CacheType cache;
+	/// Use the Pimpl idiom to hide the internals.
+	class Impl;
+	/// The pointer never changes although *pimpl_'s contents may.
+	Impl * const pimpl_;
 };
-#endif
+
+} // namespace graphics
+} // namespace lyx
+
+#endif // GRAPHICSCACHE_H