Disk cache: Reference CL for the implementation of file format version 3.

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.
+
+#ifndef NET_DISK_CACHE_V3_BACKEND_WORKER_H_
+#define NET_DISK_CACHE_V3_BACKEND_WORKER_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 <map>
+
+namespace base {
+class MessageLoopProxy;
+}
+
+namespace disk_cache {
+
+class File;
+struct InitResult;
+class MappedFile;
+
+class BackendImplV3::Worker : public base::RefCountedThreadSafe<Worker> {
+ public:
+  Worker(const base::FilePath& path, base::MessageLoopProxy* main_thread);
+
+  // 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:
+  friend class base::RefCountedThreadSafe<Worker>;
+  typedef std::map<uint32, scoped_refptr<disk_cache::File>> FilesMap;
+
+  ~Worker();
+  void Cleanup(WorkItem* work_item);
+  void CloseFiles();
+
+  disk_cache::File* GetExternalFile(Addr address, bool for_write);
+  base::FilePath GetFileName(Addr address) const;
+
+  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();
+
+  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_;
+
+  // 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_;
+
+  bool init_;
+  bool doubling_index_;     // The index is being doubled in size;
+  uint32 user_flags_;
+
+  DISALLOW_COPY_AND_ASSIGN(Worker);
+};
+
+}  // namespace disk_cache
+
+#endif  // NET_DISK_CACHE_V3_BACKEND_WORKER_H_