xref: /aosp_15_r20/external/cronet/net/disk_cache/simple/simple_backend_version.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2013 The Chromium Authors
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_SIMPLE_SIMPLE_BACKEND_VERSION_H_
6 #define NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_VERSION_H_
7 
8 #include <stdint.h>
9 
10 namespace disk_cache {
11 
12 // Short rules helping to think about data upgrades within Simple Cache:
13 //   * ALL changes of on-disk data format, backward-compatible or not,
14 //     forward-compatible or not, require updating the |kSimpleVersion|.
15 //   * All cache Upgrades are performed on backend start, must be finished
16 //     before the new backend starts processing any incoming operations.
17 //   * If the Upgrade is not implemented for transition from
18 //     |kSimpleVersion - 1| then the whole cache directory will be cleared.
19 //   * Dropping cache data on disk or some of its parts can be a valid way to
20 //     Upgrade.
21 const uint32_t kLastCompatSparseVersion = 7;
22 const uint32_t kSimpleVersion = 9;
23 
24 // The version of the entry file(s) as written to disk. Must be updated iff the
25 // entry format changes with the overall backend version update.
26 const uint32_t kSimpleEntryVersionOnDisk = 5;
27 
28 }  // namespace disk_cache
29 
30 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_VERSION_H_
31