libs/vr/libbufferhubqueue/include/private/dvr/buffer_hub_queue_producer.h

#ifndef ANDROID_DVR_BUFFER_HUB_QUEUE_PRODUCER_H_
#define ANDROID_DVR_BUFFER_HUB_QUEUE_PRODUCER_H_

#include <gui/IGraphicBufferProducer.h>
#include <private/dvr/buffer_hub_queue_client.h>

namespace android {
namespace dvr {

class BufferHubQueueProducer : public BnGraphicBufferProducer {
 public:
  static constexpr int kNoConnectedApi = -1;

  // TODO(b/36187402) The actual implementation of BufferHubQueue's consumer
  // side logic doesn't limit the number of buffer it can acquire
  // simultaneously. We need a way for consumer logic to configure and enforce
  // that.
  static constexpr int kDefaultUndequeuedBuffers = 1;

  // Create a BufferHubQueueProducer instance by creating a new producer queue.
  static sp<BufferHubQueueProducer> Create();

  // Create a BufferHubQueueProducer instance by importing an existing prodcuer
  // queue.
  static sp<BufferHubQueueProducer> Create(
      const std::shared_ptr<ProducerQueue>& producer);

  // See |IGraphicBufferProducer::requestBuffer|
  status_t requestBuffer(int slot, sp<GraphicBuffer>* buf) override;

  // For the BufferHub based implementation. All buffers in the queue are
  // allowed to be dequeued from the consumer side. It call always returns
  // 0 for |NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS| query. Thus setting
  // |max_dequeued_buffers| here can be considered the same as setting queue
  // capacity.
  //
  // See |IGraphicBufferProducer::setMaxDequeuedBufferCount| for more info
  status_t setMaxDequeuedBufferCount(int max_dequeued_buffers) override;

  // See |IGraphicBufferProducer::setAsyncMode|
  status_t setAsyncMode(bool async) override;

  // See |IGraphicBufferProducer::dequeueBuffer|
  status_t dequeueBuffer(int* out_slot, sp<Fence>* out_fence, uint32_t width,
                         uint32_t height, PixelFormat format, uint64_t usage,
                         FrameEventHistoryDelta* outTimestamps) override;

  // See |IGraphicBufferProducer::detachBuffer|
  status_t detachBuffer(int slot) override;

  // See |IGraphicBufferProducer::detachNextBuffer|
  status_t detachNextBuffer(sp<GraphicBuffer>* out_buffer,
                            sp<Fence>* out_fence) override;

  // See |IGraphicBufferProducer::attachBuffer|
  status_t attachBuffer(int* out_slot,
                        const sp<GraphicBuffer>& buffer) override;

  // See |IGraphicBufferProducer::queueBuffer|
  status_t queueBuffer(int slot, const QueueBufferInput& input,
                       QueueBufferOutput* output) override;

  // See |IGraphicBufferProducer::cancelBuffer|
  status_t cancelBuffer(int slot, const sp<Fence>& fence) override;

  // See |IGraphicBufferProducer::query|
  status_t query(int what, int* out_value) override;

  // See |IGraphicBufferProducer::connect|
  status_t connect(const sp<IProducerListener>& listener, int api,
                   bool producer_controlled_by_app,
                   QueueBufferOutput* output) override;

  // See |IGraphicBufferProducer::disconnect|
  status_t disconnect(int api,
                      DisconnectMode mode = DisconnectMode::Api) override;

  // See |IGraphicBufferProducer::setSidebandStream|
  status_t setSidebandStream(const sp<NativeHandle>& stream) override;

  // See |IGraphicBufferProducer::allocateBuffers|
  void allocateBuffers(uint32_t width, uint32_t height, PixelFormat format,
                       uint64_t usage) override;

  // See |IGraphicBufferProducer::allowAllocation|
  status_t allowAllocation(bool allow) override;

  // See |IGraphicBufferProducer::setGenerationNumber|
  status_t setGenerationNumber(uint32_t generation_number) override;

  // See |IGraphicBufferProducer::getConsumerName|
  String8 getConsumerName() const override;

  // See |IGraphicBufferProducer::setSharedBufferMode|
  status_t setSharedBufferMode(bool shared_buffer_mode) override;

  // See |IGraphicBufferProducer::setAutoRefresh|
  status_t setAutoRefresh(bool auto_refresh) override;

  // See |IGraphicBufferProducer::setDequeueTimeout|
  status_t setDequeueTimeout(nsecs_t timeout) override;

  // See |IGraphicBufferProducer::getLastQueuedBuffer|
  status_t getLastQueuedBuffer(sp<GraphicBuffer>* out_buffer,
                               sp<Fence>* out_fence,
                               float out_transform_matrix[16]) override;

  // See |IGraphicBufferProducer::getFrameTimestamps|
  void getFrameTimestamps(FrameEventHistoryDelta* /*outDelta*/) override;

  // See |IGraphicBufferProducer::getUniqueId|
  status_t getUniqueId(uint64_t* out_id) const override;

 private:
  using LocalHandle = pdx::LocalHandle;

  // Private constructor to force use of |Create|.
  BufferHubQueueProducer() {}

  static uint64_t genUniqueId() {
    static std::atomic<uint32_t> counter{0};
    static uint64_t id = static_cast<uint64_t>(getpid()) << 32;
    return id | counter++;
  }

  // Allocate new buffer through BufferHub and add it into |queue_| for
  // bookkeeping.
  status_t AllocateBuffer(uint32_t width, uint32_t height, uint32_t layer_count,
                          PixelFormat format, uint64_t usage);

  // Remove a buffer via BufferHubRPC.
  status_t RemoveBuffer(size_t slot);

  // Concreate implementation backed by BufferHubBuffer.
  std::shared_ptr<ProducerQueue> queue_;

  // Mutex for thread safety.
  std::mutex mutex_;

  // Connect client API, should be one of the NATIVE_WINDOW_API_* flags.
  int connected_api_{kNoConnectedApi};

  // |max_buffer_count_| sets the capacity of the underlying buffer queue.
  int32_t max_buffer_count_{BufferHubQueue::kMaxQueueCapacity};

  // |max_dequeued_buffer_count_| set the maximum number of buffers that can
  // be dequeued at the same momment.
  int32_t max_dequeued_buffer_count_{1};

  // Sets how long dequeueBuffer or attachBuffer will block if a buffer or
  // slot is not yet available. The timeout is stored in milliseconds.
  int dequeue_timeout_ms_{BufferHubQueue::kNoTimeOut};

  // |generation_number_| stores the current generation number of the attached
  // producer. Any attempt to attach a buffer with a different generation
  // number will fail.
  // TOOD(b/38137191) Currently not used as we don't support
  // IGraphicBufferProducer::detachBuffer.
  uint32_t generation_number_{0};

  // |buffers_| stores the buffers that have been dequeued from
  // |dvr::BufferHubQueue|, It is initialized to invalid buffers, and gets
  // filled in with the result of |Dequeue|.
  // TODO(jwcai) The buffer allocated to a slot will also be replaced if the
  // requested buffer usage or geometry differs from that of the buffer
  // allocated to a slot.
  struct BufferHubSlot : public BufferSlot {
    BufferHubSlot() : mBufferProducer(nullptr), mIsReallocating(false) {}
    // BufferSlot comes from android framework, using m prefix to comply with
    // the name convention with the reset of data fields from BufferSlot.
    std::shared_ptr<BufferProducer> mBufferProducer;
    bool mIsReallocating;
  };
  BufferHubSlot buffers_[BufferHubQueue::kMaxQueueCapacity];

  // A uniqueId used by IGraphicBufferProducer interface.
  const uint64_t unique_id_{genUniqueId()};
};

}  // namespace dvr
}  // namespace android

#endif  // ANDROID_DVR_BUFFER_HUB_QUEUE_PRODUCER_H_