1 files changed, 48 insertions, 0 deletions
diff --git a/dom/media/mediacapabilities/KeyValueStorage.h b/dom/media/mediacapabilities/KeyValueStorage.h
new file mode 100644
index 0000000000..60d72a6c6d
--- /dev/null
+++ b/dom/media/mediacapabilities/KeyValueStorage.h
@@ -0,0 +1,48 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_KEY_VALUE_STORAGE_H
+#define MOZILLA_KEY_VALUE_STORAGE_H
+
+#include "mozilla/MozPromise.h"
+#include "nsIKeyValue.h"
+
+namespace mozilla {
+
+/* A wrapper class around kv store service, which allows storing a pair of key
+ * value permanently. The class must be used from the parent process, where
+ * there is no sandbox because it requires access to the directory that the
+ * database is located. */
+class KeyValueStorage final {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(KeyValueStorage)
+
+  /* Store permanently the value in the Key. */
+  RefPtr<GenericPromise> Put(const nsACString& aName, const nsACString& aKey,
+                             int32_t aValue);
+  /* Get the value stored in the aKey. If the aKey does not exist the promise is
+   * resolved with the value -1. */
+  typedef MozPromise<int32_t, nsresult, true> GetPromise;
+  RefPtr<GetPromise> Get(const nsACString& aName, const nsACString& aKey);
+
+  /* Clear all the key/value pairs from the aName database. */
+  RefPtr<GenericPromise> Clear(const nsACString& aName);
+
+ private:
+  /* Create, if doesn't exist, and initialize the database with a given name. */
+  RefPtr<GenericPromise> Init();
+  RefPtr<GenericPromise> Put(const nsACString& aKey, int32_t aValue);
+  RefPtr<GetPromise> Get(const nsACString& aKey);
+  RefPtr<GenericPromise> Clear();
+  ~KeyValueStorage() = default;
+
+  RefPtr<nsIKeyValueDatabase> mDatabase;
+  nsCString mDatabaseName;
+};
+
+}  // namespace mozilla
+
+#endif  // MOZILLA_KEY_VALUE_STORAGE_H