libs/vr/libbufferhub/include/private/dvr/native_buffer.h

#ifndef ANDROID_DVR_NATIVE_BUFFER_H_
#define ANDROID_DVR_NATIVE_BUFFER_H_

#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <log/log.h>
#include <ui/ANativeObjectBase.h>
#include <utils/RefBase.h>
#include <nativebase/nativebase.h>

#include <private/dvr/buffer_hub_client.h>

namespace android {
namespace dvr {

// ANativeWindowBuffer is the abstraction Android HALs and frameworks use to
// pass around hardware graphics buffers. The following classes implement this
// abstraction with different DVR backing buffers, all of which provide
// different semantics on top of ion/gralloc buffers.

// An implementation of ANativeWindowBuffer backed by an IonBuffer.
class NativeBuffer
    : public android::ANativeObjectBase<ANativeWindowBuffer, NativeBuffer,
                                        android::LightRefBase<NativeBuffer>> {
 public:
  static constexpr int kEmptyFence = -1;

  explicit NativeBuffer(const std::shared_ptr<IonBuffer>& buffer)
      : BASE(), buffer_(buffer), fence_(kEmptyFence) {
    ANativeWindowBuffer::width = buffer->width();
    ANativeWindowBuffer::height = buffer->height();
    ANativeWindowBuffer::stride = buffer->stride();
    ANativeWindowBuffer::format = buffer->format();
    ANativeWindowBuffer::usage = buffer->usage();
    handle = buffer_->handle();
  }

  virtual ~NativeBuffer() {}

  std::shared_ptr<IonBuffer> buffer() { return buffer_; }
  int fence() const { return fence_.Get(); }

  void SetFence(int fence) { fence_.Reset(fence); }

 private:
  friend class android::LightRefBase<NativeBuffer>;

  std::shared_ptr<IonBuffer> buffer_;
  pdx::LocalHandle fence_;

  NativeBuffer(const NativeBuffer&) = delete;
  void operator=(NativeBuffer&) = delete;
};

class NativeBufferProducer : public android::ANativeObjectBase<
                                 ANativeWindowBuffer, NativeBufferProducer,
                                 android::LightRefBase<NativeBufferProducer>> {
 public:
  static constexpr int kEmptyFence = -1;

  NativeBufferProducer(const std::shared_ptr<BufferProducer>& buffer,
                       EGLDisplay display, uint32_t surface_buffer_index)
      : BASE(),
        buffer_(buffer),
        surface_buffer_index_(surface_buffer_index),
        display_(display) {
    ANativeWindowBuffer::width = buffer_->width();
    ANativeWindowBuffer::height = buffer_->height();
    ANativeWindowBuffer::stride = buffer_->stride();
    ANativeWindowBuffer::format = buffer_->format();
    ANativeWindowBuffer::usage = buffer_->usage();
    ANativeWindowBuffer::handle = buffer_->native_handle();
    if (display_) {
      image_khr_ =
          eglCreateImageKHR(display_, EGL_NO_CONTEXT, EGL_NATIVE_BUFFER_ANDROID,
                            static_cast<ANativeWindowBuffer*>(this), nullptr);
    } else {
      image_khr_ = EGL_NO_IMAGE_KHR;
    }
  }

  explicit NativeBufferProducer(const std::shared_ptr<BufferProducer>& buffer)
      : NativeBufferProducer(buffer, nullptr, 0) {}

  virtual ~NativeBufferProducer() {
    if (image_khr_ != EGL_NO_IMAGE_KHR)
      eglDestroyImageKHR(display_, image_khr_);
  }

  EGLImageKHR image_khr() const { return image_khr_; }
  std::shared_ptr<BufferProducer> buffer() const { return buffer_; }
  int release_fence() const { return release_fence_.Get(); }
  uint32_t surface_buffer_index() const { return surface_buffer_index_; }

  // Return the release fence, passing ownership to the caller.
  pdx::LocalHandle ClaimReleaseFence() { return std::move(release_fence_); }

  // Post the buffer consumer, closing the acquire and release fences.
  int Post(int acquire_fence, uint64_t sequence) {
    release_fence_.Close();
    return buffer_->Post(pdx::LocalHandle(acquire_fence), sequence);
  }

  // Gain the buffer producer, closing the previous release fence if valid.
  int Gain() { return buffer_->Gain(&release_fence_); }

  // Asynchronously gain the buffer, closing the previous release fence.
  int GainAsync() {
    release_fence_.Close();
    return buffer_->GainAsync();
  }

 private:
  friend class android::LightRefBase<NativeBufferProducer>;

  std::shared_ptr<BufferProducer> buffer_;
  pdx::LocalHandle release_fence_;
  EGLImageKHR image_khr_;
  uint32_t surface_buffer_index_;
  EGLDisplay display_;

  NativeBufferProducer(const NativeBufferProducer&) = delete;
  void operator=(NativeBufferProducer&) = delete;
};

// NativeBufferConsumer is an implementation of ANativeWindowBuffer backed by a
// BufferConsumer.
class NativeBufferConsumer : public android::ANativeObjectBase<
                                 ANativeWindowBuffer, NativeBufferConsumer,
                                 android::LightRefBase<NativeBufferConsumer>> {
 public:
  static constexpr int kEmptyFence = -1;

  explicit NativeBufferConsumer(const std::shared_ptr<BufferConsumer>& buffer)
      : BASE(), buffer_(buffer), acquire_fence_(kEmptyFence), sequence_(0) {
    ANativeWindowBuffer::width = buffer_->width();
    ANativeWindowBuffer::height = buffer_->height();
    ANativeWindowBuffer::stride = buffer_->stride();
    ANativeWindowBuffer::format = buffer_->format();
    ANativeWindowBuffer::usage = buffer_->usage();
    handle = buffer_->native_handle();
  }

  virtual ~NativeBufferConsumer() {}

  std::shared_ptr<BufferConsumer> buffer() const { return buffer_; }
  int acquire_fence() const { return acquire_fence_.Get(); }
  uint64_t sequence() const { return sequence_; }

  // Return the acquire fence, passing ownership to the caller.
  pdx::LocalHandle ClaimAcquireFence() { return std::move(acquire_fence_); }

  // Acquire the underlying buffer consumer, closing the previous acquire fence
  // if valid.
  int Acquire() { return buffer_->Acquire(&acquire_fence_, &sequence_); }

  // Release the buffer consumer, closing the acquire and release fences if
  // valid.
  int Release(int release_fence) {
    acquire_fence_.Close();
    sequence_ = 0;
    return buffer_->Release(pdx::LocalHandle(release_fence));
  }

 private:
  friend class android::LightRefBase<NativeBufferConsumer>;

  std::shared_ptr<BufferConsumer> buffer_;
  pdx::LocalHandle acquire_fence_;
  uint64_t sequence_;

  NativeBufferConsumer(const NativeBufferConsumer&) = delete;
  void operator=(NativeBufferConsumer&) = delete;
};

}  // namespace dvr
}  // namespace android

#endif  // ANDROID_DVR_NATIVE_BUFFER_H_