Disk cache: First pass to add support for sparse entries....

net/disk_cache/entry_impl.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_DISK_CACHE_ENTRY_IMPL_H_
 #define NET_DISK_CACHE_ENTRY_IMPL_H_
 
 #include "base/scoped_ptr.h"
 #include "net/disk_cache/disk_cache.h"
 #include "net/disk_cache/storage_block.h"
 #include "net/disk_cache/storage_block-inl.h"
 
 namespace disk_cache {
 
 class BackendImpl;
+class SparseControl;
 
 // This class implements the Entry interface. An object of this
 // class represents a single entry on the cache.
 class EntryImpl : public Entry, public base::RefCounted<EntryImpl> {
   friend class base::RefCounted<EntryImpl>;
+  friend class SparseControl;
  public:
   EntryImpl(BackendImpl* backend, Addr address);
 
   // Entry interface.
   virtual void Doom();
   virtual void Close();
   virtual std::string GetKey() const;
   virtual base::Time GetLastUsed() const;
   virtual base::Time GetLastModified() const;
   virtual int32 GetDataSize(int index) const;
@@ skipping 60 matching lines @@
 
   // Handle the pending asynchronous IO count.
   void IncrementIoCount();
   void DecrementIoCount();
 
   // Set the access times for this entry. This method provides support for
   // the upgrade tool.
   void SetTimes(base::Time last_used, base::Time last_modified);
 
  private:
-   enum {
-     NUM_STREAMS = 3
-   };
+  enum {
+    NUM_STREAMS = 3
+  };
 
   ~EntryImpl();
 
   // Initializes the storage for an internal or external data block.
   bool CreateDataBlock(int index, int size);
 
   // Initializes the storage for an internal or external generic block.
   bool CreateBlock(int size, Addr* address);
 
   // Deletes the data pointed by address, maybe backed by files_[index].
@@ skipping 17 matching lines @@
 
   // Reads from a block data file to this object's memory buffer.
   bool MoveToLocalBuffer(int index);
 
   // Loads the external file to this object's memory buffer.
   bool ImportSeparateFile(int index, int offset, int buf_len);
 
   // Flush the in-memory data to the backing storage.
   bool Flush(int index, int size, bool async);
 
+  // Initializes the sparse control object. Returns a net error code.
+  int InitSparseData();
+
   // Logs this entry to the internal trace buffer.
   void Log(const char* msg);
 
   CacheEntryBlock entry_;     // Key related information for this entry.
   CacheRankingsBlock node_;   // Rankings related information for this entry.
   BackendImpl* backend_;      // Back pointer to the cache.
   scoped_array<char> user_buffers_[NUM_STREAMS];  // Store user data.
   scoped_refptr<File> files_[NUM_STREAMS + 1];  // Files to store external user
                                                 // data and key.
   int unreported_size_[NUM_STREAMS];  // Bytes not reported yet to the backend.
   bool doomed_;               // True if this entry was removed from the cache.
+  scoped_ptr<SparseControl> sparse_;  // Support for sparse entries.
+
   DISALLOW_EVIL_CONSTRUCTORS(EntryImpl);
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_ENTRY_IMPL_H_