Update BufferHubQueue in preparation for VrFlinger refactor.

- Expose buffer hub queue id to the client. This helpful as an id
  in queue enumeration in the DisplayManager API.
- Address log convention deviations.
- Clean up BufferHub service error paths.
- Clean up queue importing logic to query the service for queue
  parameters to avoid accidental abuse.
- Make spawning consumer queues more efficient in RPC only cases.
- Clean up ConsumerQueue constructor logic; move to pdx::Client
  base class (through BufferHubQueue) instead of pdx::ClientBase.
  ConsumerQueue::Create doesn't make sense as a ConsumerQueue can
  only be created from another queue.

Bug: 36401174
Test: build; run buffer_hub_queue-test
Change-Id: I0530f64ecb514d0f37bb13f9ce201b6ff51502b6
diff --git a/services/vr/bufferhubd/buffer_hub.cpp b/services/vr/bufferhubd/buffer_hub.cpp
index de4950e..2ce60e5 100644
--- a/services/vr/bufferhubd/buffer_hub.cpp
+++ b/services/vr/bufferhubd/buffer_hub.cpp
@@ -16,7 +16,9 @@
 #include "producer_queue_channel.h"
 
 using android::pdx::Channel;
+using android::pdx::ErrorStatus;
 using android::pdx::Message;
+using android::pdx::Status;
 using android::pdx::rpc::DispatchRemoteMethod;
 using android::pdx::default_transport::Endpoint;
 
@@ -28,9 +30,7 @@
 
 BufferHubService::~BufferHubService() {}
 
-bool BufferHubService::IsInitialized() const {
-  return BASE::IsInitialized();
-}
+bool BufferHubService::IsInitialized() const { return BASE::IsInitialized(); }
 
 std::string BufferHubService::DumpState(size_t /*max_length*/) {
   std::ostringstream stream;
@@ -374,7 +374,7 @@
   }
 }
 
-int BufferHubService::OnCreateProducerQueue(
+Status<QueueInfo> BufferHubService::OnCreateProducerQueue(
     pdx::Message& message, size_t meta_size_bytes, int usage_set_mask,
     int usage_clear_mask, int usage_deny_set_mask, int usage_deny_clear_mask) {
   // Use the producer channel id as the global queue id.
@@ -386,7 +386,7 @@
   if (const auto channel = message.GetChannel<BufferHubChannel>()) {
     ALOGE("BufferHubService::OnCreateProducerQueue: already created: queue=%d",
           queue_id);
-    return -EALREADY;
+    return ErrorStatus(EALREADY);
   }
 
   int error;
@@ -394,10 +394,10 @@
           this, queue_id, meta_size_bytes, usage_set_mask, usage_clear_mask,
           usage_deny_set_mask, usage_deny_clear_mask, &error)) {
     message.SetChannel(producer_channel);
-    return 0;
+    return {{meta_size_bytes, queue_id}};
   } else {
     ALOGE("BufferHubService::OnCreateBuffer: Failed to create producer!!");
-    return error;
+    return ErrorStatus(-error);
   }
 }
 
diff --git a/services/vr/bufferhubd/buffer_hub.h b/services/vr/bufferhubd/buffer_hub.h
index 8a7dca8..150e399 100644
--- a/services/vr/bufferhubd/buffer_hub.h
+++ b/services/vr/bufferhubd/buffer_hub.h
@@ -7,6 +7,7 @@
 
 #include <hardware/gralloc.h>
 #include <pdx/service.h>
+#include <private/dvr/bufferhub_rpc.h>
 
 namespace android {
 namespace dvr {
@@ -73,9 +74,9 @@
           slice_count(slice_count),
           name(name) {}
 
-    BufferInfo(int id, size_t consumer_count, size_t capacity, int usage_set_mask,
-               int usage_clear_mask, int usage_deny_set_mask,
-               int usage_deny_clear_mask)
+    BufferInfo(int id, size_t consumer_count, size_t capacity,
+               int usage_set_mask, int usage_clear_mask,
+               int usage_deny_set_mask, int usage_deny_clear_mask)
         : id(id),
           type(kProducerQueueType),
           consumer_count(consumer_count),
@@ -168,9 +169,9 @@
                                int format, int usage, size_t meta_size_bytes,
                                size_t slice_count);
   int OnGetPersistentBuffer(pdx::Message& message, const std::string& name);
-  int OnCreateProducerQueue(pdx::Message& message, size_t meta_size_bytes,
-                            int usage_set_mask, int usage_clear_mask,
-                            int usage_deny_set_mask, int usage_deny_clear_mask);
+  pdx::Status<QueueInfo> OnCreateProducerQueue(
+      pdx::Message& message, size_t meta_size_bytes, int usage_set_mask,
+      int usage_clear_mask, int usage_deny_set_mask, int usage_deny_clear_mask);
 
   BufferHubService(const BufferHubService&) = delete;
   void operator=(const BufferHubService&) = delete;
diff --git a/services/vr/bufferhubd/consumer_queue_channel.cpp b/services/vr/bufferhubd/consumer_queue_channel.cpp
index ae87acd..cc16f1f 100644
--- a/services/vr/bufferhubd/consumer_queue_channel.cpp
+++ b/services/vr/bufferhubd/consumer_queue_channel.cpp
@@ -40,6 +40,11 @@
           *producer, &ProducerQueueChannel::OnCreateConsumerQueue, message);
       return true;
 
+    case BufferHubRPC::GetQueueInfo::Opcode:
+      DispatchRemoteMethod<BufferHubRPC::GetQueueInfo>(
+          *producer, &ProducerQueueChannel::OnGetQueueInfo, message);
+      return true;
+
     case BufferHubRPC::ConsumerQueueImportBuffers::Opcode:
       DispatchRemoteMethod<BufferHubRPC::ConsumerQueueImportBuffers>(
           *this, &ConsumerQueueChannel::OnConsumerQueueImportBuffers, message);
diff --git a/services/vr/bufferhubd/producer_queue_channel.cpp b/services/vr/bufferhubd/producer_queue_channel.cpp
index 7952642..7741058 100644
--- a/services/vr/bufferhubd/producer_queue_channel.cpp
+++ b/services/vr/bufferhubd/producer_queue_channel.cpp
@@ -3,6 +3,9 @@
 #include "consumer_queue_channel.h"
 #include "producer_channel.h"
 
+using android::pdx::ErrorStatus;
+using android::pdx::Message;
+using android::pdx::Status;
 using android::pdx::RemoteChannelHandle;
 using android::pdx::rpc::DispatchRemoteMethod;
 
@@ -58,6 +61,11 @@
           *this, &ProducerQueueChannel::OnCreateConsumerQueue, message);
       return true;
 
+    case BufferHubRPC::GetQueueInfo::Opcode:
+      DispatchRemoteMethod<BufferHubRPC::GetQueueInfo>(
+          *this, &ProducerQueueChannel::OnGetQueueInfo, message);
+      return true;
+
     case BufferHubRPC::ProducerQueueAllocateBuffers::Opcode:
       DispatchRemoteMethod<BufferHubRPC::ProducerQueueAllocateBuffers>(
           *this, &ProducerQueueChannel::OnProducerQueueAllocateBuffers,
@@ -84,8 +92,8 @@
                     usage_deny_clear_mask_);
 }
 
-std::pair<RemoteChannelHandle, size_t>
-ProducerQueueChannel::OnCreateConsumerQueue(Message& message) {
+Status<RemoteChannelHandle> ProducerQueueChannel::OnCreateConsumerQueue(
+    Message& message) {
   ATRACE_NAME("ProducerQueueChannel::OnCreateConsumerQueue");
   ALOGD_IF(TRACE, "ProducerQueueChannel::OnCreateConsumerQueue: channel_id=%d",
            channel_id());
@@ -97,7 +105,7 @@
         "ProducerQueueChannel::OnCreateConsumerQueue: failed to push consumer "
         "channel: %s",
         status.GetErrorMessage().c_str());
-    REPLY_ERROR_RETURN(message, status.error(), {});
+    return ErrorStatus(ENOMEM);
   }
 
   const auto channel_status = service()->SetChannel(
@@ -108,13 +116,17 @@
         "ProducerQueueChannel::OnCreateConsumerQueue: failed to set new "
         "consumer channel: %s",
         channel_status.GetErrorMessage().c_str());
-    REPLY_ERROR_RETURN(message, channel_status.error(), {});
+    return ErrorStatus(ENOMEM);
   }
 
-  return std::make_pair(status.take(), meta_size_bytes_);
+  return {status.take()};
 }
 
-std::vector<std::pair<RemoteChannelHandle, size_t>>
+Status<QueueInfo> ProducerQueueChannel::OnGetQueueInfo(Message&) {
+  return {{meta_size_bytes_, buffer_id()}};
+}
+
+Status<std::vector<std::pair<RemoteChannelHandle, size_t>>>
 ProducerQueueChannel::OnProducerQueueAllocateBuffers(Message& message,
                                                      int width, int height,
                                                      int format, int usage,
@@ -135,7 +147,7 @@
         "not permitted. Violating usage_deny_set_mask, the following bits "
         "shall not be set: %d.",
         usage, usage_deny_set_mask_);
-    REPLY_ERROR_RETURN(message, EINVAL, buffer_handles);
+    return ErrorStatus(EINVAL);
   }
 
   if (~usage & usage_deny_clear_mask_) {
@@ -144,7 +156,7 @@
         "not permitted. Violating usage_deny_clear_mask, the following bits "
         "must be set: %d.",
         usage, usage_deny_clear_mask_);
-    REPLY_ERROR_RETURN(message, EINVAL, buffer_handles);
+    return ErrorStatus(EINVAL);
   }
 
   // Force set mask and clear mask. Note that |usage_set_mask_| takes precedence
@@ -152,24 +164,24 @@
   int effective_usage = (usage & ~usage_clear_mask_) | usage_set_mask_;
 
   for (size_t i = 0; i < buffer_count; i++) {
-    auto buffer_handle_slot = AllocateBuffer(message, width, height, format,
-                                             effective_usage, slice_count);
-    if (!buffer_handle_slot.first) {
+    auto status = AllocateBuffer(message, width, height, format,
+                                 effective_usage, slice_count);
+    if (!status) {
       ALOGE(
-          "ProducerQueueChannel::OnProducerQueueAllocateBuffers: failed to "
+          "ProducerQueueChannel::OnProducerQueueAllocateBuffers: Failed to "
           "allocate new buffer.");
-      REPLY_ERROR_RETURN(message, ENOMEM, buffer_handles);
+      return ErrorStatus(status.error());
     }
-    buffer_handles.emplace_back(std::move(buffer_handle_slot.first),
-                                buffer_handle_slot.second);
+    buffer_handles.push_back(status.take());
   }
 
-  return buffer_handles;
+  return {std::move(buffer_handles)};
 }
 
-std::pair<RemoteChannelHandle, size_t> ProducerQueueChannel::AllocateBuffer(
-    Message& message, int width, int height, int format, int usage,
-    size_t slice_count) {
+Status<std::pair<RemoteChannelHandle, size_t>>
+ProducerQueueChannel::AllocateBuffer(Message& message, int width, int height,
+                                     int format, int usage,
+                                     size_t slice_count) {
   ATRACE_NAME("ProducerQueueChannel::AllocateBuffer");
   ALOGD_IF(TRACE,
            "ProducerQueueChannel::AllocateBuffer: producer_channel_id=%d",
@@ -177,7 +189,7 @@
 
   if (capacity_ >= BufferHubRPC::kMaxQueueCapacity) {
     ALOGE("ProducerQueueChannel::AllocateBuffer: reaches kMaxQueueCapacity.");
-    return {};
+    return ErrorStatus(E2BIG);
   }
 
   // Here we are creating a new BufferHubBuffer, initialize the producer
@@ -189,7 +201,7 @@
   if (!status) {
     ALOGE("ProducerQueueChannel::AllocateBuffer: failed to push channel: %s",
           status.GetErrorMessage().c_str());
-    return {};
+    return ErrorStatus(status.error());
   }
 
   ALOGD_IF(TRACE,
@@ -199,14 +211,14 @@
   auto buffer_handle = status.take();
 
   int error;
-  const auto producer_channel = ProducerChannel::Create(
-      service(), buffer_id, width, height, format, usage,
-      meta_size_bytes_, slice_count, &error);
+  const auto producer_channel =
+      ProducerChannel::Create(service(), buffer_id, width, height, format,
+                              usage, meta_size_bytes_, slice_count, &error);
   if (!producer_channel) {
     ALOGE(
         "ProducerQueueChannel::AllocateBuffer: Failed to create "
         "BufferHubBuffer producer!!");
-    return {};
+    return ErrorStatus(ENOMEM);
   }
 
   ALOGD_IF(
@@ -221,7 +233,7 @@
         "ProducerQueueChannel::AllocateBuffer: failed to set producer channel "
         "for new BufferHubBuffer: %s",
         channel_status.GetErrorMessage().c_str());
-    return {};
+    return ErrorStatus(ENOMEM);
   }
 
   // Register the newly allocated buffer's channel_id into the first empty
@@ -235,7 +247,7 @@
     ALOGE(
         "ProducerQueueChannel::AllocateBuffer: Cannot find empty slot for new "
         "buffer allocation.");
-    return {};
+    return ErrorStatus(E2BIG);
   }
 
   buffers_[slot] = producer_channel;
@@ -250,29 +262,29 @@
     consumer_channel->RegisterNewBuffer(producer_channel, slot);
   }
 
-  return {std::move(buffer_handle), slot};
+  return {{std::move(buffer_handle), slot}};
 }
 
-int ProducerQueueChannel::OnProducerQueueDetachBuffer(Message& /*message*/,
-                                                      size_t slot) {
+Status<void> ProducerQueueChannel::OnProducerQueueDetachBuffer(
+    Message& /*message*/, size_t slot) {
   if (buffers_[slot].expired()) {
     ALOGE(
         "ProducerQueueChannel::OnProducerQueueDetachBuffer: trying to detach "
         "an invalid buffer producer at slot %zu",
         slot);
-    return -EINVAL;
+    return ErrorStatus(EINVAL);
   }
 
   if (capacity_ == 0) {
     ALOGE(
         "ProducerQueueChannel::OnProducerQueueDetachBuffer: trying to detach a "
         "buffer producer while the queue's capacity is already zero.");
-    return -EINVAL;
+    return ErrorStatus(EINVAL);
   }
 
   buffers_[slot].reset();
   capacity_--;
-  return 0;
+  return {};
 }
 
 void ProducerQueueChannel::AddConsumer(ConsumerQueueChannel* channel) {
diff --git a/services/vr/bufferhubd/producer_queue_channel.h b/services/vr/bufferhubd/producer_queue_channel.h
index 49611d4..a12a37d 100644
--- a/services/vr/bufferhubd/producer_queue_channel.h
+++ b/services/vr/bufferhubd/producer_queue_channel.h
@@ -3,6 +3,7 @@
 
 #include "buffer_hub.h"
 
+#include <pdx/status.h>
 #include <private/dvr/bufferhub_rpc.h>
 
 namespace android {
@@ -10,17 +11,14 @@
 
 class ProducerQueueChannel : public BufferHubChannel {
  public:
-  using Message = pdx::Message;
-  using RemoteChannelHandle = pdx::RemoteChannelHandle;
-
   static std::shared_ptr<ProducerQueueChannel> Create(
       BufferHubService* service, int channel_id, size_t meta_size_bytes,
       int usage_set_mask, int usage_clear_mask, int usage_deny_set_mask,
       int usage_deny_clear_mask, int* error);
   ~ProducerQueueChannel() override;
 
-  bool HandleMessage(Message& message) override;
-  void HandleImpulse(Message& message) override;
+  bool HandleMessage(pdx::Message& message) override;
+  void HandleImpulse(pdx::Message& message) override;
 
   BufferInfo GetBufferInfo() const override;
 
@@ -28,19 +26,22 @@
   // producer queue.
   // Returns a handle for the service channel, as well as the size of the
   // metadata associated with the queue.
-  std::pair<RemoteChannelHandle, size_t> OnCreateConsumerQueue(
-      Message& message);
+  pdx::Status<pdx::RemoteChannelHandle> OnCreateConsumerQueue(
+      pdx::Message& message);
+
+  pdx::Status<QueueInfo> OnGetQueueInfo(pdx::Message& message);
 
   // Allocate a new BufferHubProducer according to the input spec. Client may
   // handle this as if a new producer is created through kOpCreateBuffer.
-  std::vector<std::pair<RemoteChannelHandle, size_t>>
-  OnProducerQueueAllocateBuffers(Message& message, int width, int height,
+  pdx::Status<std::vector<std::pair<pdx::RemoteChannelHandle, size_t>>>
+  OnProducerQueueAllocateBuffers(pdx::Message& message, int width, int height,
                                  int format, int usage, size_t slice_count,
                                  size_t buffer_count);
 
   // Detach a BufferHubProducer indicated by |slot|. Note that the buffer must
   // be in Gain'ed state for the producer queue to detach.
-  int OnProducerQueueDetachBuffer(Message& message, size_t slot);
+  pdx::Status<void> OnProducerQueueDetachBuffer(pdx::Message& message,
+                                                size_t slot);
 
   void AddConsumer(ConsumerQueueChannel* channel);
   void RemoveConsumer(ConsumerQueueChannel* channel);
@@ -56,10 +57,9 @@
   // and our return type is a RemoteChannelHandle.
   // Returns the remote channdel handle and the slot number for the newly
   // allocated buffer.
-  std::pair<RemoteChannelHandle, size_t> AllocateBuffer(Message& message,
-                                                        int width, int height,
-                                                        int format, int usage,
-                                                        size_t slice_count);
+  pdx::Status<std::pair<pdx::RemoteChannelHandle, size_t>> AllocateBuffer(
+      pdx::Message& message, int width, int height, int format, int usage,
+      size_t slice_count);
 
   // Size of the meta data associated with all the buffers allocated from the
   // queue. Now we assume the metadata size is immutable once the queue is