1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_DISK_CACHE_FLASH_ENTRY_IMPL_H_ 6 #define NET_DISK_CACHE_FLASH_ENTRY_IMPL_H_ 7 8 #include <string> 9 10 #include "base/memory/ref_counted.h" 11 #include "base/memory/scoped_ptr.h" 12 #include "net/base/net_export.h" 13 #include "net/disk_cache/disk_cache.h" 14 #include "net/disk_cache/flash/internal_entry.h" 15 16 namespace base { 17 18 class MessageLoopProxy; 19 20 } // namespace base 21 22 namespace disk_cache { 23 24 class InternalEntry; 25 class IOBuffer; 26 class LogStore; 27 28 // We use split objects to minimize the context switches between the main thread 29 // and the cache thread in the most common case of creating a new entry. 30 // 31 // All calls on a new entry are served synchronously. When an object is 32 // destructed (via final Close() call), a message is posted to the cache thread 33 // to save the object to storage. 34 // 35 // When an entry is not new, every asynchronous call is posted to the cache 36 // thread, just as before; synchronous calls like GetKey() and GetDataSize() are 37 // served from the main thread. 38 class NET_EXPORT_PRIVATE FlashEntryImpl 39 : public Entry, 40 public base::RefCountedThreadSafe<FlashEntryImpl> { 41 friend class base::RefCountedThreadSafe<FlashEntryImpl>; 42 public: 43 FlashEntryImpl(const std::string& key, 44 LogStore* store, 45 base::MessageLoopProxy* cache_thread); 46 FlashEntryImpl(int32 id, 47 LogStore* store, 48 base::MessageLoopProxy* cache_thread); 49 50 int Init(const CompletionCallback& callback); 51 52 // disk_cache::Entry interface. 53 virtual void Doom() OVERRIDE; 54 virtual void Close() OVERRIDE; 55 virtual std::string GetKey() const OVERRIDE; 56 virtual base::Time GetLastUsed() const OVERRIDE; 57 virtual base::Time GetLastModified() const OVERRIDE; 58 virtual int32 GetDataSize(int index) const OVERRIDE; 59 virtual int ReadData(int index, int offset, IOBuffer* buf, int buf_len, 60 const CompletionCallback& callback) OVERRIDE; 61 virtual int WriteData(int index, int offset, IOBuffer* buf, int buf_len, 62 const CompletionCallback& callback, 63 bool truncate) OVERRIDE; 64 virtual int ReadSparseData(int64 offset, IOBuffer* buf, int buf_len, 65 const CompletionCallback& callback) OVERRIDE; 66 virtual int WriteSparseData(int64 offset, IOBuffer* buf, int buf_len, 67 const CompletionCallback& callback) OVERRIDE; 68 virtual int GetAvailableRange(int64 offset, int len, int64* start, 69 const CompletionCallback& callback) OVERRIDE; 70 virtual bool CouldBeSparse() const OVERRIDE; 71 virtual void CancelSparseIO() OVERRIDE; 72 virtual int ReadyForSparseIO(const CompletionCallback& callback) OVERRIDE; 73 74 private: 75 void OnInitComplete(scoped_ptr<KeyAndStreamSizes> key_and_stream_sizes); 76 virtual ~FlashEntryImpl(); 77 78 bool init_; 79 std::string key_; 80 int stream_sizes_[kFlashLogStoreEntryNumStreams]; 81 82 // Used if |this| is an newly created entry. 83 scoped_refptr<InternalEntry> new_internal_entry_; 84 85 // Used if |this| is an existing entry. 86 scoped_refptr<InternalEntry> old_internal_entry_; 87 88 // Copy of the callback for asynchronous calls on |old_internal_entry_|. 89 CompletionCallback callback_; 90 91 scoped_refptr<base::MessageLoopProxy> cache_thread_; 92 93 DISALLOW_COPY_AND_ASSIGN(FlashEntryImpl); 94 }; 95 96 } // namespace disk_cache 97 98 #endif // NET_DISK_CACHE_FLASH_ENTRY_IMPL_H_ 99
