1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim:set ts=2 sw=2 sts=2 et cindent: */ 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_KEY_VALUE_STORAGE_H 8 #define MOZILLA_KEY_VALUE_STORAGE_H 9 10 #include "mozilla/MozPromise.h" 11 #include "nsIKeyValue.h" 12 13 namespace mozilla { 14 15 /* A wrapper class around kv store service, which allows storing a pair of key 16 * value permanently. The class must be used from the parent process, where 17 * there is no sandbox because it requires access to the directory that the 18 * database is located. */ 19 class KeyValueStorage final { 20 public: 21 NS_INLINE_DECL_THREADSAFE_REFCOUNTING(KeyValueStorage) 22 23 /* Store permanently the value in the Key. */ 24 RefPtr<GenericPromise> Put(const nsACString& aName, const nsACString& aKey, 25 int32_t aValue); 26 /* Get the value stored in the aKey. If the aKey does not exist the promise is 27 * resolved with the value -1. */ 28 typedef MozPromise<int32_t, nsresult, true> GetPromise; 29 RefPtr<GetPromise> Get(const nsACString& aName, const nsACString& aKey); 30 31 /* Clear all the key/value pairs from the aName database. */ 32 RefPtr<GenericPromise> Clear(const nsACString& aName); 33 34 private: 35 /* Create, if doesn't exist, and initialize the database with a given name. */ 36 RefPtr<GenericPromise> Init(); 37 RefPtr<GenericPromise> Put(const nsACString& aKey, int32_t aValue); 38 RefPtr<GetPromise> Get(const nsACString& aKey); 39 RefPtr<GenericPromise> Clear(); 40 ~KeyValueStorage() = default; 41 42 RefPtr<nsIKeyValueDatabase> mDatabase; 43 nsCString mDatabaseName; 44 }; 45 46 } // namespace mozilla 47 48 #endif // MOZILLA_KEY_VALUE_STORAGE_H 49