Break up and rename buffer_hub_cilent.{h, cpp}

Code in buffer_hub_cilent.{h,cpp} was the main client side
implementation of bufferhub. With years of developements, the content
of it was complicated enough to deserved separated files. Also rename
stuff for clarification.

old names:

              +-------------------+
              |  BufferHubBuffer  |
              +---------^---------+
                        |
+------------------+    |     +------------------+
|  BufferProducer  +----+-----+  BufferConsumer  |
+------------------+          +------------------+

new names:

               +-----------------+
               |  BufferHubBase  |
               +--------^--------+
                        |
+------------------+    |     +------------------+
|  ProducerBuffer  +----+-----+  ConsumerBuffer  |
+------------------+          +------------------+

Rename rationale:

1/ BufferProducer was originally poorly named and gets easily confused
   with IGraphicBufferProducer. Actually, BufferProducer is a single
   buffer that can produce (i.e. write) data into a buffer, but it
   doesn't produce buffer. On the other hand, IGraphicBufferProducer
   is the producer end of a BufferQueue and it is used to produce buffers.

2/ BufferConsumer was originally poorly named and gets easily confused
   with IGraphicBufferConsumer. Actually, BufferConsumer is a single
   buffer that can consume (i.e. read) data from a buffer, but it
   doesn't consume buffer. On the other hand, IGraphicBufferConsumer
   is the consumer end of a BufferQueue and it is used to consume
   buffers.

3/ BufferHubBuffer is a pure base class and cannot be used
   standalone. The old name suggests that it's a buffer object backed
   by BufferHub, which might leads to confusion. Also, this rename is
   in preparation of rename DetachedBuffer to BufferHubBuffer.

Bug: 116855254
Test: Build system
Change-Id: Id545648f5bdc7660e58f7bb49722651ae3bcca70
diff --git a/libs/vr/libbufferhub/consumer_buffer.cpp b/libs/vr/libbufferhub/consumer_buffer.cpp
new file mode 100644
index 0000000..4e8c36b
--- /dev/null
+++ b/libs/vr/libbufferhub/consumer_buffer.cpp
@@ -0,0 +1,183 @@
+#include <private/dvr/consumer_buffer.h>
+
+using android::pdx::LocalChannelHandle;
+using android::pdx::LocalHandle;
+using android::pdx::Status;
+
+namespace android {
+namespace dvr {
+
+ConsumerBuffer::ConsumerBuffer(LocalChannelHandle channel)
+    : BASE(std::move(channel)) {
+  const int ret = ImportBuffer();
+  if (ret < 0) {
+    ALOGE("ConsumerBuffer::ConsumerBuffer: Failed to import buffer: %s",
+          strerror(-ret));
+    Close(ret);
+  }
+}
+
+std::unique_ptr<ConsumerBuffer> ConsumerBuffer::Import(
+    LocalChannelHandle channel) {
+  ATRACE_NAME("ConsumerBuffer::Import");
+  ALOGD_IF(TRACE, "ConsumerBuffer::Import: channel=%d", channel.value());
+  return ConsumerBuffer::Create(std::move(channel));
+}
+
+std::unique_ptr<ConsumerBuffer> ConsumerBuffer::Import(
+    Status<LocalChannelHandle> status) {
+  return Import(status ? status.take()
+                       : LocalChannelHandle{nullptr, -status.error()});
+}
+
+int ConsumerBuffer::LocalAcquire(DvrNativeBufferMetadata* out_meta,
+                                 LocalHandle* out_fence) {
+  if (!out_meta)
+    return -EINVAL;
+
+  // Only check producer bit and this consumer buffer's particular consumer bit.
+  // The buffer is can be acquired iff: 1) producer bit is set; 2) consumer bit
+  // is not set.
+  uint64_t buffer_state = buffer_state_->load();
+  if (!BufferHubDefs::IsBufferPosted(buffer_state, buffer_state_bit())) {
+    ALOGE("ConsumerBuffer::LocalAcquire: not posted, id=%d state=%" PRIx64
+          " buffer_state_bit=%" PRIx64 ".",
+          id(), buffer_state, buffer_state_bit());
+    return -EBUSY;
+  }
+
+  // Copy the canonical metadata.
+  void* metadata_ptr = reinterpret_cast<void*>(&metadata_header_->metadata);
+  memcpy(out_meta, metadata_ptr, sizeof(DvrNativeBufferMetadata));
+  // Fill in the user_metadata_ptr in address space of the local process.
+  if (out_meta->user_metadata_size) {
+    out_meta->user_metadata_ptr =
+        reinterpret_cast<uint64_t>(user_metadata_ptr_);
+  } else {
+    out_meta->user_metadata_ptr = 0;
+  }
+
+  uint64_t fence_state = fence_state_->load();
+  // If there is an acquire fence from producer, we need to return it.
+  if (fence_state & BufferHubDefs::kProducerStateBit) {
+    *out_fence = shared_acquire_fence_.Duplicate();
+  }
+
+  // Set the consumer bit unique to this consumer.
+  BufferHubDefs::ModifyBufferState(buffer_state_, 0ULL, buffer_state_bit());
+  return 0;
+}
+
+int ConsumerBuffer::Acquire(LocalHandle* ready_fence) {
+  return Acquire(ready_fence, nullptr, 0);
+}
+
+int ConsumerBuffer::Acquire(LocalHandle* ready_fence, void* meta,
+                            size_t user_metadata_size) {
+  ATRACE_NAME("ConsumerBuffer::Acquire");
+
+  if (const int error = CheckMetadata(user_metadata_size))
+    return error;
+
+  DvrNativeBufferMetadata canonical_meta;
+  if (const int error = LocalAcquire(&canonical_meta, ready_fence))
+    return error;
+
+  if (meta && user_metadata_size) {
+    void* metadata_src =
+        reinterpret_cast<void*>(canonical_meta.user_metadata_ptr);
+    if (metadata_src) {
+      memcpy(meta, metadata_src, user_metadata_size);
+    } else {
+      ALOGW("ConsumerBuffer::Acquire: no user-defined metadata.");
+    }
+  }
+
+  auto status = InvokeRemoteMethod<BufferHubRPC::ConsumerAcquire>();
+  if (!status)
+    return -status.error();
+  return 0;
+}
+
+int ConsumerBuffer::AcquireAsync(DvrNativeBufferMetadata* out_meta,
+                                 LocalHandle* out_fence) {
+  ATRACE_NAME("ConsumerBuffer::AcquireAsync");
+
+  if (const int error = LocalAcquire(out_meta, out_fence))
+    return error;
+
+  auto status = SendImpulse(BufferHubRPC::ConsumerAcquire::Opcode);
+  if (!status)
+    return -status.error();
+  return 0;
+}
+
+int ConsumerBuffer::LocalRelease(const DvrNativeBufferMetadata* meta,
+                                 const LocalHandle& release_fence) {
+  if (const int error = CheckMetadata(meta->user_metadata_size))
+    return error;
+
+  // Check invalid state transition.
+  uint64_t buffer_state = buffer_state_->load();
+  if (!BufferHubDefs::IsBufferAcquired(buffer_state)) {
+    ALOGE("ConsumerBuffer::LocalRelease: not acquired id=%d state=%" PRIx64 ".",
+          id(), buffer_state);
+    return -EBUSY;
+  }
+
+  // On release, only the user requested metadata is copied back into the shared
+  // memory for metadata. Since there are multiple consumers, it doesn't make
+  // sense to send the canonical metadata back to the producer. However, one of
+  // the consumer can still choose to write up to user_metadata_size bytes of
+  // data into user_metadata_ptr.
+  if (meta->user_metadata_ptr && meta->user_metadata_size) {
+    void* metadata_src = reinterpret_cast<void*>(meta->user_metadata_ptr);
+    memcpy(user_metadata_ptr_, metadata_src, meta->user_metadata_size);
+  }
+
+  // Send out the release fence through the shared epoll fd. Note that during
+  // releasing the producer is not expected to be polling on the fence.
+  if (const int error = UpdateSharedFence(release_fence, shared_release_fence_))
+    return error;
+
+  // For release operation, the client don't need to change the state as it's
+  // bufferhubd's job to flip the produer bit once all consumers are released.
+  return 0;
+}
+
+int ConsumerBuffer::Release(const LocalHandle& release_fence) {
+  ATRACE_NAME("ConsumerBuffer::Release");
+
+  DvrNativeBufferMetadata meta;
+  if (const int error = LocalRelease(&meta, release_fence))
+    return error;
+
+  return ReturnStatusOrError(InvokeRemoteMethod<BufferHubRPC::ConsumerRelease>(
+      BorrowedFence(release_fence.Borrow())));
+}
+
+int ConsumerBuffer::ReleaseAsync() {
+  DvrNativeBufferMetadata meta;
+  return ReleaseAsync(&meta, LocalHandle());
+}
+
+int ConsumerBuffer::ReleaseAsync(const DvrNativeBufferMetadata* meta,
+                                 const LocalHandle& release_fence) {
+  ATRACE_NAME("ConsumerBuffer::ReleaseAsync");
+
+  if (const int error = LocalRelease(meta, release_fence))
+    return error;
+
+  return ReturnStatusOrError(
+      SendImpulse(BufferHubRPC::ConsumerRelease::Opcode));
+}
+
+int ConsumerBuffer::Discard() { return Release(LocalHandle()); }
+
+int ConsumerBuffer::SetIgnore(bool ignore) {
+  return ReturnStatusOrError(
+      InvokeRemoteMethod<BufferHubRPC::ConsumerSetIgnore>(ignore));
+}
+
+}  // namespace dvr
+}  // namespace android