1 files changed, 94 insertions, 0 deletions
diff --git a/dom/media/systemservices/MediaSystemResourceClient.h b/dom/media/systemservices/MediaSystemResourceClient.h
new file mode 100644
index 000000000..29e769a92
--- /dev/null
+++ b/dom/media/systemservices/MediaSystemResourceClient.h
@@ -0,0 +1,94 @@
+/* -*- 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/. */
+
+#if !defined(MediaSystemResourceClient_h_)
+#define MediaSystemResourceClient_h_
+
+#include "MediaSystemResourceManager.h"
+#include "MediaSystemResourceTypes.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/media/MediaSystemResourceTypes.h"
+#include "mozilla/Monitor.h"
+#include "mozilla/RefPtr.h"
+
+namespace mozilla {
+
+class MediaSystemResourceManager;
+
+
+/**
+ * This is a base class for listener callbacks.
+ * This callback is invoked when the media system resource reservation state
+ * is changed.
+ */
+class MediaSystemResourceReservationListener {
+public:
+  virtual void ResourceReserved() = 0;
+  virtual void ResourceReserveFailed() = 0;
+};
+
+/**
+ * MediaSystemResourceClient is used to reserve a media system resource
+ * like hw decoder. When system has a limitation of a media resource,
+ * use this class to mediate use rights of the resource.
+ */
+class MediaSystemResourceClient
+{
+public:
+
+  // Enumeration for the valid decoding states
+  enum ResourceState {
+    RESOURCE_STATE_START,
+    RESOURCE_STATE_WAITING,
+    RESOURCE_STATE_ACQUIRED,
+    RESOURCE_STATE_NOT_ACQUIRED,
+    RESOURCE_STATE_END
+  };
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaSystemResourceClient)
+
+  explicit MediaSystemResourceClient(MediaSystemResourceType aReourceType);
+
+  bool SetListener(MediaSystemResourceReservationListener* aListener);
+
+  // Try to acquire media resource asynchronously.
+  // If the resource is used by others, wait until acquired.
+  void Acquire();
+
+  // Try to acquire media resource synchronously. If the resource is not immediately
+  // available, fail to acquire it.
+  // return false if resource is not acquired.
+  // return true if resource is acquired.
+  //
+  // This function should not be called on ImageBridge thread.
+  // It should be used only for compatibility with legacy code.
+  bool AcquireSyncNoWait();
+
+  void ReleaseResource();
+
+private:
+  ~MediaSystemResourceClient();
+
+  RefPtr<MediaSystemResourceManager> mManager;
+  const MediaSystemResourceType mResourceType;
+  const uint32_t mId;
+
+  // Modified only by MediaSystemResourceManager.
+  // Accessed and modified with MediaSystemResourceManager::mReentrantMonitor held.
+  MediaSystemResourceReservationListener* mListener;
+  ResourceState mResourceState;
+  bool mIsSync;
+  ReentrantMonitor* mAcquireSyncWaitMonitor;
+  bool* mAcquireSyncWaitDone;
+
+  static mozilla::Atomic<uint32_t> sSerialCounter;
+
+  friend class MediaSystemResourceManager;
+};
+
+} // namespace mozilla
+
+#endif