Disk cache v3 ref2

net/disk_cache/v3/backend_worker.h

 // Copyright (c) 2012 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.
 
-// See net/disk_cache/disk_cache.h for the public interface of the cache.
+#ifndef NET_DISK_CACHE_V3_BACKEND_WORKER_H_
+#define NET_DISK_CACHE_V3_BACKEND_WORKER_H_
 
-#ifndef NET_DISK_CACHE_BACKEND_IMPL_H_
-#define NET_DISK_CACHE_BACKEND_IMPL_H_
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/files/file_path.h"
+#include "net/disk_cache/Addr.h"
+#include "net/disk_cache/block_files.h"
+#include "net/disk_cache/v3/backend_impl_v3.h"
 
-#include "base/containers/hash_tables.h"
-#include "base/files/file_path.h"
-#include "base/timer/timer.h"
-#include "net/disk_cache/block_files.h"
-#include "net/disk_cache/disk_cache.h"
-#include "net/disk_cache/eviction.h"
-#include "net/disk_cache/in_flight_backend_io.h"
-#include "net/disk_cache/rankings.h"
-#include "net/disk_cache/stats.h"
-#include "net/disk_cache/stress_support.h"
-#include "net/disk_cache/trace.h"
+#include <map>
+
+namespace base {
+class MessageLoopProxy;
+}
 
 namespace disk_cache {
 
-// This class implements the Backend interface. An object of this
-// class handles the operations of the cache for a particular profile.
-class NET_EXPORT_PRIVATE BackendImpl : public Backend {
-  friend class Eviction;
+class File;
+struct InitResult;
+class MappedFile;
+
+class BackendImplV3::Worker : public base::RefCountedThreadSafe<Worker> {
  public:
-  BackendImpl(const base::FilePath& path, base::MessageLoopProxy* cache_thread,
-              net::NetLog* net_log);
+  Worker(const base::FilePath& path, base::MessageLoopProxy* main_thread);
 
-  // Performs general initialization for this current instance of the cache.
-  int Init(const CompletionCallback& callback);
+  // Construction and destruction helpers.
+  int Init(uint32 flags, scoped_ptr<InitResult>* result);
+  int Restart(uint32 flags, scoped_ptr<InitResult>* result);
+
+  int GrowIndex(uint32 flags, scoped_ptr<InitResult>* result);
+  int GrowFiles(uint32 flags, scoped_ptr<InitResult>* result);
+
+  int Delete(Addr address);
+  int Close(Addr address);
+
+  void OnDoWork(WorkItem* work_item);
+  void DoneWithItem(WorkItem* work_item);
+
+  MappedFile* GetMappedFile(Addr address) {
+    return block_files_->GetFile(address);
+  }
+
+  disk_cache::File* GetBackingFile(Addr address, bool for_write);
+
+  disk_cache::File* GetBackupIndexFile();
+  void CloseBackupIndexFile();
+
+  bool IsValid();
+
+  // Timer notification.
+  void OnTimer();
 
  private:
-  void CleanupCache();
+  friend class base::RefCountedThreadSafe<Worker>;
+  typedef std::map<uint32, scoped_refptr<disk_cache::File>> FilesMap;
 
-  // Returns the full name for an external storage file.
+  ~Worker();
+  void Cleanup(WorkItem* work_item);
+  void CloseFiles();
+
+  disk_cache::File* GetExternalFile(Addr address, bool for_write);
   base::FilePath GetFileName(Addr address) const;
 
-  // Creates a new backing file for the cache index.
   bool CreateBackingStore(disk_cache::File* file);
+  bool CreateExtraTable(int extra_len);
   bool InitBackingStore(bool* file_created);
+  bool LoadIndex(InitResult* init_result);
+  bool CheckIndexFile(MappedFile* file);
+  bool InitStats(IndexHeaderV3* index, InitResult* result);
+  int GrowDone();
 
-  // Reports an uncommon, recoverable error.
-  void ReportError(int error);
+  base::FilePath path_;
+  scoped_refptr<base::MessageLoopProxy> main_thread_;
+  scoped_refptr<MappedFile> index_header_;
+  scoped_refptr<MappedFile> main_table_;
+  scoped_refptr<MappedFile> extra_table_;
+  scoped_refptr<MappedFile> index_backup_;
+  scoped_ptr<BlockFiles> block_files_;
+  FilesMap files_;
+  WorkItem* cleanup_work_item_;
 
-  // Performs basic checks on the index file. Returns false on failure.
-  bool CheckIndex();
+  // Valid while growing files:
+  scoped_refptr<MappedFile> big_index_header_;
+  scoped_refptr<MappedFile> big_main_table_;
+  scoped_refptr<MappedFile> big_extra_table_;
+  scoped_refptr<MappedFile> big_extra_temp_table_;
+  scoped_ptr<BlockFiles> big_block_files_;
 
-  base::FilePath path_;  // Path to the folder used as backing storage.
-  BlockFiles block_files_;  // Set of files used to store all data.
-  bool init_;  // controls the initialization of the system.
+  bool init_;
+  bool doubling_index_;     // The index is being doubled in size;
+  uint32 user_flags_;
 
-  DISALLOW_COPY_AND_ASSIGN(BackendImpl);
+  DISALLOW_COPY_AND_ASSIGN(Worker);
 };
 
 }  // namespace disk_cache
 
-#endif  // NET_DISK_CACHE_BACKEND_IMPL_H_
+#endif  // NET_DISK_CACHE_V3_BACKEND_WORKER_H_