SimpleCache: merge the first and second stream in one file

net/disk_cache/simple/simple_util.h

 // Copyright (c) 2013 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_SIMPLE_SIMPLE_UTIL_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_UTIL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 38 matching lines @@
 
 // Given the size of a file holding a stream in the simple backend and the key
 // to an entry, returns the number of bytes in the stream.
 NET_EXPORT_PRIVATE int32 GetDataSizeFromKeyAndFileSize(const std::string& key,
                                                        int64 file_size);
 
 // Given the size of a stream in the simple backend and the key to an entry,
 // returns the number of bytes in the file.
 NET_EXPORT_PRIVATE int64 GetFileSizeFromKeyAndDataSize(const std::string& key,
                                                        int32 data_size);
+// Given the stream index, returns the number of the file the stream is stored
+// in.
+NET_EXPORT_PRIVATE int GetFileIndexFromStreamIndex(int stream_index);
+
+// Given the data size for all streams and a file index, gives the offset of the
+// last EOF record.
+NET_EXPORT_PRIVATE int GetLastEOFRecordOffset(int file_index,
+                                              const int data_size[]);
 
 // Given the key to an entry, and an offset into a stream on that entry, returns
 // the file offset corresponding to |data_offset|.
-NET_EXPORT_PRIVATE int64 GetFileOffsetFromKeyAndDataOffset(
-    const std::string& key,
-    int data_offset);
+NET_EXPORT_PRIVATE int64 GetFileOffsetFromDataOffset(const std::string& key,
+                                                     int data_offset,
+                                                     int index,
+                                                     int stream_1_size);

[pasko, 2013/09/17 11:29:01]

Originally I did not like this stream_1_size in the utility function because it
is error-prone for callers to add this parameter, this could be avoided by
encapsulating the stream <-> file mapping details in a compact class. Out of
that came the suggestion to advance the SimpleEntryStat. Apparently something
did not work out to the original goal, I guess the roadblock was the necessity
to make the class available wider and replace the simple_util in parts? Well, by
itself it is rather a positive move.

[clamy, 2013/09/17 13:59:42]

Done.

 
 // Fills |out_time| with the time the file last modified time. Unlike the
 // functions in platform_file.h, the time resolution is milliseconds.
 NET_EXPORT_PRIVATE bool GetMTime(const base::FilePath& path,
                                  base::Time* out_mtime);
 }  // namespace simple_backend
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_UTIL_H_