[Chromecast] Upgrade to new CMA backend API

chromecast/public/media/media_component_device.h

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CHROMECAST_PUBLIC_MEDIA_MEDIA_COMPONENT_DEVICE_H_
-#define CHROMECAST_PUBLIC_MEDIA_MEDIA_COMPONENT_DEVICE_H_
-
-#include <stdint.h>
-#include <string>
-
-#include "cast_key_system.h"
-
-namespace chromecast {
-namespace media {
-class CastDecoderBuffer;
-class DecryptContext;
-
-// Common base interface for both platform-specific audio and video pipeline
-// backends.  Both follow this state machine:
-//                       +------------- kRunning <--+
-//                       |                 ^        |
-//                       v                 |        |
-// kUninitialized <--> kIdle  -------------+        |
-//                       ^                 |        |
-//                       |                 v        |
-//                       +------------- kPaused <---+
-// {any state} --> kError
-// kError --> kUninitialized
-//
-// Notes:
-// - Hardware resources should be acquired when transitioning from the
-//   |kUninitialized| state to the |kIdle| state.
-// - Buffers will be pushed only in the kRunning or kPaused states.
-// - The end of stream is signaled through a special buffer.
-//   Once the end of stream buffer is fed, no other buffer
-//   will be fed until the FSM goes through the kIdle state again.
-// - In both kPaused and kRunning states, frames can be fed.
-//   However, frames are possibly rendered only in the kRunning state.
-// - In the kRunning state, frames are rendered according to the clock rate.
-// - All the hardware resources must be released in the |kError| state.
-class MediaComponentDevice {
- public:
-  enum State {
-    kStateUninitialized,
-    kStateIdle,
-    kStateRunning,
-    kStatePaused,
-    kStateError,
-  };
-
-  enum FrameStatus {
-    kFrameSuccess,
-    kFrameFailed,
-    kFramePending,
-  };
-
-  // Interface for receiving status when PushFrame has completed.
-  class FrameStatusCB {
-   public:
-    virtual ~FrameStatusCB() {}
-    virtual void Run(FrameStatus status) = 0;
-  };
-
-  // Client callbacks interface
-  class Client {
-   public:
-    virtual ~Client() {}
-    virtual void OnEndOfStream() = 0;
-  };
-
-  // The statistics are computed since the media component left the idle state.
-  // For video, a sample is defined as a frame.
-  struct Statistics {
-    uint64_t decoded_bytes;
-    uint64_t decoded_samples;
-    uint64_t dropped_samples;
-  };
-
-  // Info on pipeline latency: amount of data in pipeline not rendered yet,
-  // and timestamp of system clock (must be CLOCK_MONOTONIC) at which delay
-  // measurement was taken.  Both times in microseconds.
-  struct RenderingDelay {
-    RenderingDelay()
-        : delay_microseconds(INT64_MIN), timestamp_microseconds(INT64_MIN) {}
-    RenderingDelay(int64_t delay_microseconds_in,
-                   int64_t timestamp_microseconds_in)
-        : delay_microseconds(delay_microseconds_in),
-          timestamp_microseconds(timestamp_microseconds_in) {}
-    int64_t delay_microseconds;
-    int64_t timestamp_microseconds;
-  };
-
-  virtual ~MediaComponentDevice() {}
-
-  // Registers |client| as the media event handler.  Implementation
-  // takes ownership of |client| and call OnEndOfStream when an end-of-stream
-  // buffer is processed.
-  virtual void SetClient(Client* client) = 0;
-
-  // Changes the state and performs any necessary transitions.
-  // Returns true when successful.
-  virtual bool SetState(State new_state) = 0;
-
-  // Returns the current state of the media component.
-  virtual State GetState() const = 0;
-
-  // Sets the time where rendering should start.
-  // Return true when successful.
-  // Will only be invoked in state kStateIdle.
-  virtual bool SetStartPts(int64_t microseconds) = 0;
-
-  // Pushes a frame.  If the implementation cannot push the buffer
-  // now, it must store the buffer, return |kFramePending| and execute the push
-  // at a later time when it becomes possible to do so.  The implementation must
-  // then invoke |completion_cb|.  Pushing a pending frame should be aborted if
-  // the state returns to kStateIdle, and |completion_cb| need not be invoked.
-  // If |kFramePending| is returned, the pipeline will stop pushing any further
-  // buffers until the |completion_cb| is invoked.
-  // Ownership: |decrypt_context|, |buffer|, |completion_cb| are all owned by
-  // the implementation and must be deleted once no longer needed (even in the
-  // case where |completion_cb| is not called).
-  // |completion_cb| should be only be invoked to indicate completion of a
-  // pending buffer push - not for the immediate |kFrameSuccess| return case.
-  virtual FrameStatus PushFrame(DecryptContext* decrypt_context,
-                                CastDecoderBuffer* buffer,
-                                FrameStatusCB* completion_cb) = 0;
-
-  // Returns the pipeline latency: i.e. the amount of data
-  // in the pipeline that have not been rendered yet, in microseconds.
-  // Returns delay = INT64_MIN if the latency is not available.
-  virtual RenderingDelay GetRenderingDelay() const = 0;
-
-  // Returns the playback statistics since the last transition from idle state.
-  // Returns true when successful.
-  // Is only invoked in state kStateRunning.
-  virtual bool GetStatistics(Statistics* stats) const = 0;
-};
-
-}  // namespace media
-}  // namespace chromecast
-
-#endif  // CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_COMPONENT_DEVICE_H_