block_files.h revision 3345a6884c488ff3a535c2c9acdd33d74b37e311
1c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// Copyright (c) 2010 The Chromium Authors. All rights reserved. 2c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use of this source code is governed by a BSD-style license that can be 3c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// found in the LICENSE file. 4c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// See net/disk_cache/disk_cache.h for the public interface. 6c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 7c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#ifndef NET_DISK_CACHE_BLOCK_FILES_H__ 8c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#define NET_DISK_CACHE_BLOCK_FILES_H__ 93345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#pragma once 10c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 11c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include <vector> 12c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 13c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/file_path.h" 143345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#include "base/gtest_prod_util.h" 153345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#include "base/scoped_ptr.h" 16c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "net/disk_cache/addr.h" 17c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "net/disk_cache/mapped_file.h" 18c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 193345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrickclass ThreadChecker; 20c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 213345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merricknamespace disk_cache { 22c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 23c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// This class handles the set of block-files open by the disk cache. 24c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottclass BlockFiles { 25c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott public: 263345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick explicit BlockFiles(const FilePath& path); 27c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott ~BlockFiles(); 28c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 29c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Performs the object initialization. create_files indicates if the backing 30c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // files should be created or just open. 31c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool Init(bool create_files); 32c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 33c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Returns the file that stores a given address. 34c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* GetFile(Addr address); 35c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 36c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Creates a new entry on a block file. block_type indicates the size of block 37c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // to be used (as defined on cache_addr.h), block_count is the number of 38c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // blocks to allocate, and block_address is the address of the new entry. 39c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool CreateBlock(FileType block_type, int block_count, Addr* block_address); 40c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 41c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Removes an entry from the block files. If deep is true, the storage is zero 42c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // filled; otherwise the entry is removed but the data is not altered (must be 43c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // already zeroed). 44c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott void DeleteBlock(Addr address, bool deep); 45c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 46c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Close all the files and set the internal state to be initializad again. The 47c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // cache is being purged. 48c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott void CloseFiles(); 49c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 50c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Sends UMA stats. 51c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void ReportStats(); 52c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 533345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick // Returns true if the blocks pointed by a given address are currently used. 543345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick // This method is only intended for debugging. 553345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick bool IsValid(Addr address); 563345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 57c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott private: 58c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Set force to true to overwrite the file if it exists. 59c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool CreateBlockFile(int index, FileType file_type, bool force); 60c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool OpenBlockFile(int index); 61c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 62c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Attemp to grow this file. Fails if the file cannot be extended anymore. 63c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool GrowBlockFile(MappedFile* file, BlockFileHeader* header); 64c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 65c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Returns the appropriate file to use for a new block. 66c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* FileForNewBlock(FileType block_type, int block_count); 67c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 68c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Returns the next block file on this chain, creating new files if needed. 69c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* NextFile(const MappedFile* file); 70c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 71c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Creates an empty block file and returns its index. 72c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int CreateNextBlockFile(FileType block_type); 73c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 74c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Removes a chained block file that is now empty. 75c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott void RemoveEmptyFile(FileType block_type); 76c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 77c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Restores the header of a potentially inconsistent file. 78c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool FixBlockFileHeader(MappedFile* file); 79c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 80c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Retrieves stats for the given file index. 81c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void GetFileStats(int index, int* used_count, int* load); 82c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 83c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Returns the filename for a given file index. 84c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FilePath Name(int index); 85c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 86c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool init_; 87c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott char* zero_buffer_; // Buffer to speed-up cleaning deleted entries. 88c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FilePath path_; // Path to the backing folder. 89c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott std::vector<MappedFile*> block_files_; // The actual files. 903345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick scoped_ptr<ThreadChecker> thread_checker_; 91c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 923345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick FRIEND_TEST_ALL_PREFIXES(DiskCacheTest, BlockFiles_ZeroSizeFile); 933345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick FRIEND_TEST_ALL_PREFIXES(DiskCacheTest, BlockFiles_InvalidFile); 943345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick FRIEND_TEST_ALL_PREFIXES(DiskCacheTest, BlockFiles_Stats); 95c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 96c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch DISALLOW_COPY_AND_ASSIGN(BlockFiles); 97c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott}; 98c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 99c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} // namespace disk_cache 100c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 101c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#endif // NET_DISK_CACHE_BLOCK_FILES_H__ 102