dom/cache/QuotaClient.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_cache_QuotaClient_h
   8 #define mozilla_dom_cache_QuotaClient_h
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/dom/cache/Types.h"
  12 #include "mozilla/dom/quota/Client.h"
  13 #include "mozIStorageConnection.h"
  14
  15 namespace mozilla::dom::cache {
  16
  17 already_AddRefed<quota::Client> CreateQuotaClient();
  18
  19 /**
  20  * The following functions are used to access the directory padding file. The
  21  * directory padding file lives in DOM Cache base directory
  22  * (e.g. foo.com/cache/.padding). It is used to keep the current overall padding
  23  * size for an origin, so that the QuotaManager doesn't need to access the
  24  * database when getting quota clients' usage.
  25  *
  26  * For the directory padding file, it's only accessed on Quota IO thread
  27  * (for getting current usage) and Cache IO threads (for tracking padding size
  28  * change). Besides, the padding file is protected by a mutex lock held by
  29  * CacheQuotaClient.
  30  *
  31  * Each padding file should only take 8 bytes (int64_t) to record the overall
  32  * padding size. Besides, we use the temporary padding file to indicate if the
  33  * previous action is completed successfully. If the temporary file exists, it
  34  * represents that the previous action is failed and the content of padding file
  35  * cannot be trusted, and we need to restore the padding file from the database.
  36  */
  37
  38 nsresult RestorePaddingFile(nsIFile* aBaseDir, mozIStorageConnection* aConn);
  39
  40 nsresult WipePaddingFile(const CacheDirectoryMetadata& aDirectoryMetadata,
  41                          nsIFile* aBaseDir);
  42
  43 extern const nsLiteralString kCachesSQLiteFilename;
  44
  45 }  // namespace mozilla::dom::cache
  46
  47 #endif  // mozilla_dom_cache_QuotaClient_h