libs/ui/tests/BufferHubBuffer_test.cpp - platform/frameworks/native - Git at Google

 /*
  * Copyright 2018 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "BufferHubBufferTest"

 #include <errno.h>
 #include <sys/epoll.h>

 #include <android/hardware_buffer.h>
 #include <cutils/native_handle.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #include <hidl/ServiceManagement.h>
 #include <hwbinder/IPCThreadState.h>
 #include <ui/BufferHubBuffer.h>
 #include <ui/BufferHubEventFd.h>

 namespace android {

 namespace {

 using ::android::BufferHubDefs::AnyClientAcquired;
 using ::android::BufferHubDefs::AnyClientGained;
 using ::android::BufferHubDefs::AnyClientPosted;
 using ::android::BufferHubDefs::IsClientAcquired;
 using ::android::BufferHubDefs::IsClientGained;
 using ::android::BufferHubDefs::IsClientPosted;
 using ::android::BufferHubDefs::IsClientReleased;
 using ::android::BufferHubDefs::kMetadataHeaderSize;
 using ::testing::IsNull;
 using ::testing::NotNull;

 const int kWidth = 640;
 const int kHeight = 480;
 const int kLayerCount = 1;
 const int kFormat = HAL_PIXEL_FORMAT_RGBA_8888;
 const int kUsage = 0;
 const AHardwareBuffer_Desc kDesc = {kWidth, kHeight,        kLayerCount,  kFormat,
                                     kUsage, /*stride=*/0UL, /*rfu0=*/0UL, /*rfu1=*/0ULL};
 const size_t kUserMetadataSize = 1;

 class BufferHubBufferTest : public ::testing::Test {
 protected:
     void SetUp() override { android::hardware::ProcessState::self()->startThreadPool(); }
 };

 bool cmpAHardwareBufferDesc(const AHardwareBuffer_Desc& desc, const AHardwareBuffer_Desc& other) {
     // Not comparing stride because it's unknown before allocation
     return desc.format == other.format && desc.height == other.height &&
             desc.layers == other.layers && desc.usage == other.usage && desc.width == other.width;
 }

 class BufferHubBufferStateTransitionTest : public BufferHubBufferTest {
 protected:
     void SetUp() override {
         BufferHubBufferTest::SetUp();
         CreateTwoClientsOfABuffer();
     }

     std::unique_ptr<BufferHubBuffer> b1;
     uint32_t b1ClientMask = 0U;
     std::unique_ptr<BufferHubBuffer> b2;
     uint32_t b2ClientMask = 0U;

 private:
     // Creates b1 and b2 as the clients of the same buffer for testing.
     void CreateTwoClientsOfABuffer();
 };

 void BufferHubBufferStateTransitionTest::CreateTwoClientsOfABuffer() {
     b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage, kUserMetadataSize);
     ASSERT_THAT(b1, NotNull());
     b1ClientMask = b1->client_state_mask();
     ASSERT_NE(b1ClientMask, 0U);

     native_handle_t* token = b1->Duplicate();
     ASSERT_THAT(token, NotNull());

     // TODO(b/122543147): use a movalbe wrapper for token
     b2 = BufferHubBuffer::Import(token);
     native_handle_close(token);
     native_handle_delete(token);
     ASSERT_THAT(b2, NotNull());

     b2ClientMask = b2->client_state_mask();
     ASSERT_NE(b2ClientMask, 0U);
     ASSERT_NE(b2ClientMask, b1ClientMask);
 }

 TEST_F(BufferHubBufferTest, CreateBufferFails) {
     // Buffer Creation will fail: BLOB format requires height to be 1.
     auto b1 = BufferHubBuffer::Create(kWidth, /*height=*/2, kLayerCount,
                                       /*format=*/HAL_PIXEL_FORMAT_BLOB, kUsage, kUserMetadataSize);

     EXPECT_THAT(b1, IsNull());

     // Buffer Creation will fail: user metadata size too large.
     auto b2 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                       /*userMetadataSize=*/std::numeric_limits<size_t>::max());

     EXPECT_THAT(b2, IsNull());

     // Buffer Creation will fail: user metadata size too large.
     const size_t userMetadataSize = std::numeric_limits<size_t>::max() - kMetadataHeaderSize;
     auto b3 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                       userMetadataSize);

     EXPECT_THAT(b3, IsNull());
 }

 TEST_F(BufferHubBufferTest, CreateBuffer) {
     auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                       kUserMetadataSize);
     ASSERT_THAT(b1, NotNull());
     EXPECT_TRUE(b1->IsConnected());
     EXPECT_TRUE(b1->IsValid());
     EXPECT_TRUE(cmpAHardwareBufferDesc(b1->desc(), kDesc));
     EXPECT_EQ(b1->user_metadata_size(), kUserMetadataSize);
 }

 TEST_F(BufferHubBufferTest, DuplicateAndImportBuffer) {
     auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                       kUserMetadataSize);
     ASSERT_THAT(b1, NotNull());
     EXPECT_TRUE(b1->IsValid());

     native_handle_t* token = b1->Duplicate();
     EXPECT_TRUE(token);

     // The detached buffer should still be valid.
     EXPECT_TRUE(b1->IsConnected());
     EXPECT_TRUE(b1->IsValid());

     std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
     native_handle_close(token);
     native_handle_delete(token);

     ASSERT_THAT(b2, NotNull());
     EXPECT_TRUE(b2->IsValid());

     EXPECT_TRUE(cmpAHardwareBufferDesc(b1->desc(), b2->desc()));
     EXPECT_EQ(b1->user_metadata_size(), b2->user_metadata_size());

     // These two buffer instances are based on the same physical buffer under the
     // hood, so they should share the same id.
     EXPECT_EQ(b1->id(), b2->id());
     // We use client_state_mask() to tell those two instances apart.
     EXPECT_NE(b1->client_state_mask(), b2->client_state_mask());

     // Both buffer instances should be in released state currently.
     EXPECT_TRUE(b1->IsReleased());
     EXPECT_TRUE(b2->IsReleased());

     // The event fd should behave like duped event fds.
     const BufferHubEventFd& eventFd1 = b1->eventFd();
     ASSERT_GE(eventFd1.get(), 0);
     const BufferHubEventFd& eventFd2 = b2->eventFd();
     ASSERT_GE(eventFd2.get(), 0);

     base::unique_fd epollFd(epoll_create(64));
     ASSERT_GE(epollFd.get(), 0);

     // Add eventFd1 to epoll set, and signal eventFd2.
     epoll_event e = {.events = EPOLLIN | EPOLLET, .data = {.u32 = 0}};
     ASSERT_EQ(epoll_ctl(epollFd.get(), EPOLL_CTL_ADD, eventFd1.get(), &e), 0) << strerror(errno);

     std::array<epoll_event, 1> events;
     EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);

     eventFd2.signal();
     EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 1);

     // The epoll fd is edge triggered, so it only responds to the eventFd once.
     EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);

     eventFd2.signal();
     eventFd2.clear();
     EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);
 }

 TEST_F(BufferHubBufferTest, ImportFreedBuffer) {
     auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                       kUserMetadataSize);
     ASSERT_THAT(b1, NotNull());
     EXPECT_TRUE(b1->IsValid());

     native_handle_t* token = b1->Duplicate();
     EXPECT_TRUE(token);

     // Explicitly destroy b1. Backend buffer should be freed and token becomes invalid
     b1.reset();

     // TODO(b/122543147): use a movalbe wrapper for token
     std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
     native_handle_close(token);
     native_handle_delete(token);

     // Import should fail with INVALID_TOKEN
     EXPECT_THAT(b2, IsNull());
 }

 // nullptr must not crash the service
 TEST_F(BufferHubBufferTest, ImportNullToken) {
     auto b1 = BufferHubBuffer::Import(nullptr);
     EXPECT_THAT(b1, IsNull());
 }

 TEST_F(BufferHubBufferTest, ImportInvalidToken) {
     native_handle_t* token = native_handle_create(/*numFds=*/0, /*numInts=*/1);
     token->data[0] = 0;

     auto b1 = BufferHubBuffer::Import(token);
     native_handle_delete(token);

     EXPECT_THAT(b1, IsNull());
 }

 TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromReleasedState) {
     ASSERT_TRUE(b1->IsReleased());

     // Successful gaining the buffer should change the buffer state bit of b1 to
     // gained state, other client state bits to released state.
     EXPECT_EQ(b1->Gain(), 0);
     EXPECT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));
 }

 TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromGainedState) {
     ASSERT_EQ(b1->Gain(), 0);
     auto current_buffer_state = b1->buffer_state();
     ASSERT_TRUE(IsClientGained(current_buffer_state, b1ClientMask));

     // Gaining from gained state by the same client should not return error.
     EXPECT_EQ(b1->Gain(), 0);

     // Gaining from gained state by another client should return error.
     EXPECT_EQ(b2->Gain(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromAcquiredState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_EQ(b2->Acquire(), 0);
     ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

     // Gaining from acquired state should fail.
     EXPECT_EQ(b1->Gain(), -EBUSY);
     EXPECT_EQ(b2->Gain(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromOtherClientInPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

     // Gaining a buffer who has other posted client should succeed.
     EXPECT_EQ(b1->Gain(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromSelfInPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

     // A posted client should be able to gain the buffer when there is no other clients in
     // acquired state.
     EXPECT_EQ(b2->Gain(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromOtherInGainedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));

     EXPECT_EQ(b2->Post(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromSelfInGainedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));

     EXPECT_EQ(b1->Post(), 0);
     auto current_buffer_state = b1->buffer_state();
     EXPECT_TRUE(IsClientReleased(current_buffer_state, b1ClientMask));
     EXPECT_TRUE(IsClientPosted(current_buffer_state, b2ClientMask));
 }

 TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

     // Post from posted state should fail.
     EXPECT_EQ(b1->Post(), -EBUSY);
     EXPECT_EQ(b2->Post(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromAcquiredState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_EQ(b2->Acquire(), 0);
     ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

     // Posting from acquired state should fail.
     EXPECT_EQ(b1->Post(), -EBUSY);
     EXPECT_EQ(b2->Post(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromReleasedState) {
     ASSERT_TRUE(b1->IsReleased());

     // Posting from released state should fail.
     EXPECT_EQ(b1->Post(), -EBUSY);
     EXPECT_EQ(b2->Post(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromSelfInPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(IsClientPosted(b1->buffer_state(), b2ClientMask));

     // Acquire from posted state should pass.
     EXPECT_EQ(b2->Acquire(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromOtherInPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(IsClientPosted(b1->buffer_state(), b2ClientMask));

     // Acquire from released state should fail, although there are other clients
     // in posted state.
     EXPECT_EQ(b1->Acquire(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromSelfInAcquiredState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_EQ(b2->Acquire(), 0);
     auto current_buffer_state = b1->buffer_state();
     ASSERT_TRUE(IsClientAcquired(current_buffer_state, b2ClientMask));

     // Acquiring from acquired state by the same client should not error out.
     EXPECT_EQ(b2->Acquire(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromReleasedState) {
     ASSERT_TRUE(b1->IsReleased());

     // Acquiring form released state should fail.
     EXPECT_EQ(b1->Acquire(), -EBUSY);
     EXPECT_EQ(b2->Acquire(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromGainedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_TRUE(AnyClientGained(b1->buffer_state()));

     // Acquiring from gained state should fail.
     EXPECT_EQ(b1->Acquire(), -EBUSY);
     EXPECT_EQ(b2->Acquire(), -EBUSY);
 }

 TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInReleasedState) {
     ASSERT_TRUE(b1->IsReleased());

     EXPECT_EQ(b1->Release(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInGainedState) {
     ASSERT_TRUE(b1->IsReleased());
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_TRUE(AnyClientGained(b1->buffer_state()));

     EXPECT_EQ(b1->Release(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInPostedState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

     EXPECT_EQ(b2->Release(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInAcquiredState) {
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);
     ASSERT_EQ(b2->Acquire(), 0);
     ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

     EXPECT_EQ(b2->Release(), 0);
 }

 TEST_F(BufferHubBufferStateTransitionTest, BasicUsage) {
     // 1 producer buffer and 1 consumer buffer initialised in testcase setup.
     // Test if this set of basic operation succeed:
     // Producer post three times to the consumer, and released by consumer.
     for (int i = 0; i < 3; ++i) {
         ASSERT_EQ(b1->Gain(), 0);
         ASSERT_EQ(b1->Post(), 0);
         ASSERT_EQ(b2->Acquire(), 0);
         ASSERT_EQ(b2->Release(), 0);
     }
 }

 TEST_F(BufferHubBufferTest, createNewConsumerAfterGain) {
     // Create a poducer buffer and gain.
     std::unique_ptr<BufferHubBuffer> b1 =
             BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                     kUserMetadataSize);
     ASSERT_THAT(b1, NotNull());
     ASSERT_EQ(b1->Gain(), 0);

     // Create a consumer of the buffer and test if the consumer can acquire the
     // buffer if producer posts.
     // TODO(b/122543147): use a movalbe wrapper for token
     native_handle_t* token = b1->Duplicate();
     ASSERT_TRUE(token);

     std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
     native_handle_close(token);
     native_handle_delete(token);

     ASSERT_THAT(b2, NotNull());
     ASSERT_NE(b1->client_state_mask(), b2->client_state_mask());

     ASSERT_EQ(b1->Post(), 0);
     EXPECT_EQ(b2->Acquire(), 0);
 }

 TEST_F(BufferHubBufferTest, createNewConsumerAfterPost) {
     // Create a poducer buffer and post.
     std::unique_ptr<BufferHubBuffer> b1 =
             BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
                                     kUserMetadataSize);
     ASSERT_EQ(b1->Gain(), 0);
     ASSERT_EQ(b1->Post(), 0);

     // Create a consumer of the buffer and test if the consumer can acquire the
     // buffer if producer posts.
     // TODO(b/122543147): use a movalbe wrapper for token
     native_handle_t* token = b1->Duplicate();
     ASSERT_TRUE(token);

     std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
     native_handle_close(token);
     native_handle_delete(token);

     ASSERT_THAT(b2, NotNull());
     ASSERT_NE(b1->client_state_mask(), b2->client_state_mask());

     EXPECT_EQ(b2->Acquire(), 0);
 }

 } // namespace

 } // namespace android
	/*
	* Copyright 2018 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "BufferHubBufferTest"

	#include <errno.h>
	#include <sys/epoll.h>

	#include <android/hardware_buffer.h>
	#include <cutils/native_handle.h>
	#include <gmock/gmock.h>
	#include <gtest/gtest.h>
	#include <hidl/ServiceManagement.h>
	#include <hwbinder/IPCThreadState.h>
	#include <ui/BufferHubBuffer.h>
	#include <ui/BufferHubEventFd.h>

	namespace android {

	namespace {

	using ::android::BufferHubDefs::AnyClientAcquired;
	using ::android::BufferHubDefs::AnyClientGained;
	using ::android::BufferHubDefs::AnyClientPosted;
	using ::android::BufferHubDefs::IsClientAcquired;
	using ::android::BufferHubDefs::IsClientGained;
	using ::android::BufferHubDefs::IsClientPosted;
	using ::android::BufferHubDefs::IsClientReleased;
	using ::android::BufferHubDefs::kMetadataHeaderSize;
	using ::testing::IsNull;
	using ::testing::NotNull;

	const int kWidth = 640;
	const int kHeight = 480;
	const int kLayerCount = 1;
	const int kFormat = HAL_PIXEL_FORMAT_RGBA_8888;
	const int kUsage = 0;
	const AHardwareBuffer_Desc kDesc = {kWidth, kHeight, kLayerCount, kFormat,
	kUsage, /stride=/0UL, /rfu0=/0UL, /rfu1=/0ULL};
	const size_t kUserMetadataSize = 1;

	class BufferHubBufferTest : public ::testing::Test {
	protected:
	void SetUp() override { android::hardware::ProcessState::self()->startThreadPool(); }
	};

	bool cmpAHardwareBufferDesc(const AHardwareBuffer_Desc& desc, const AHardwareBuffer_Desc& other) {
	// Not comparing stride because it's unknown before allocation
	return desc.format == other.format && desc.height == other.height &&
	desc.layers == other.layers && desc.usage == other.usage && desc.width == other.width;
	}

	class BufferHubBufferStateTransitionTest : public BufferHubBufferTest {
	protected:
	void SetUp() override {
	BufferHubBufferTest::SetUp();
	CreateTwoClientsOfABuffer();
	}

	std::unique_ptr<BufferHubBuffer> b1;
	uint32_t b1ClientMask = 0U;
	std::unique_ptr<BufferHubBuffer> b2;
	uint32_t b2ClientMask = 0U;

	private:
	// Creates b1 and b2 as the clients of the same buffer for testing.
	void CreateTwoClientsOfABuffer();
	};

	void BufferHubBufferStateTransitionTest::CreateTwoClientsOfABuffer() {
	b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage, kUserMetadataSize);
	ASSERT_THAT(b1, NotNull());
	b1ClientMask = b1->client_state_mask();
	ASSERT_NE(b1ClientMask, 0U);

	native_handle_t* token = b1->Duplicate();
	ASSERT_THAT(token, NotNull());

	// TODO(b/122543147): use a movalbe wrapper for token
	b2 = BufferHubBuffer::Import(token);
	native_handle_close(token);
	native_handle_delete(token);
	ASSERT_THAT(b2, NotNull());

	b2ClientMask = b2->client_state_mask();
	ASSERT_NE(b2ClientMask, 0U);
	ASSERT_NE(b2ClientMask, b1ClientMask);
	}

	TEST_F(BufferHubBufferTest, CreateBufferFails) {
	// Buffer Creation will fail: BLOB format requires height to be 1.
	auto b1 = BufferHubBuffer::Create(kWidth, /height=/2, kLayerCount,
	/format=/HAL_PIXEL_FORMAT_BLOB, kUsage, kUserMetadataSize);

	EXPECT_THAT(b1, IsNull());

	// Buffer Creation will fail: user metadata size too large.
	auto b2 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	/userMetadataSize=/std::numeric_limits<size_t>::max());

	EXPECT_THAT(b2, IsNull());

	// Buffer Creation will fail: user metadata size too large.
	const size_t userMetadataSize = std::numeric_limits<size_t>::max() - kMetadataHeaderSize;
	auto b3 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	userMetadataSize);

	EXPECT_THAT(b3, IsNull());
	}

	TEST_F(BufferHubBufferTest, CreateBuffer) {
	auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	kUserMetadataSize);
	ASSERT_THAT(b1, NotNull());
	EXPECT_TRUE(b1->IsConnected());
	EXPECT_TRUE(b1->IsValid());
	EXPECT_TRUE(cmpAHardwareBufferDesc(b1->desc(), kDesc));
	EXPECT_EQ(b1->user_metadata_size(), kUserMetadataSize);
	}

	TEST_F(BufferHubBufferTest, DuplicateAndImportBuffer) {
	auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	kUserMetadataSize);
	ASSERT_THAT(b1, NotNull());
	EXPECT_TRUE(b1->IsValid());

	native_handle_t* token = b1->Duplicate();
	EXPECT_TRUE(token);

	// The detached buffer should still be valid.
	EXPECT_TRUE(b1->IsConnected());
	EXPECT_TRUE(b1->IsValid());

	std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
	native_handle_close(token);
	native_handle_delete(token);

	ASSERT_THAT(b2, NotNull());
	EXPECT_TRUE(b2->IsValid());

	EXPECT_TRUE(cmpAHardwareBufferDesc(b1->desc(), b2->desc()));
	EXPECT_EQ(b1->user_metadata_size(), b2->user_metadata_size());

	// These two buffer instances are based on the same physical buffer under the
	// hood, so they should share the same id.
	EXPECT_EQ(b1->id(), b2->id());
	// We use client_state_mask() to tell those two instances apart.
	EXPECT_NE(b1->client_state_mask(), b2->client_state_mask());

	// Both buffer instances should be in released state currently.
	EXPECT_TRUE(b1->IsReleased());
	EXPECT_TRUE(b2->IsReleased());

	// The event fd should behave like duped event fds.
	const BufferHubEventFd& eventFd1 = b1->eventFd();
	ASSERT_GE(eventFd1.get(), 0);
	const BufferHubEventFd& eventFd2 = b2->eventFd();
	ASSERT_GE(eventFd2.get(), 0);

	base::unique_fd epollFd(epoll_create(64));
	ASSERT_GE(epollFd.get(), 0);

	// Add eventFd1 to epoll set, and signal eventFd2.
	epoll_event e = {.events = EPOLLIN \| EPOLLET, .data = {.u32 = 0}};
	ASSERT_EQ(epoll_ctl(epollFd.get(), EPOLL_CTL_ADD, eventFd1.get(), &e), 0) << strerror(errno);

	std::array<epoll_event, 1> events;
	EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);

	eventFd2.signal();
	EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 1);

	// The epoll fd is edge triggered, so it only responds to the eventFd once.
	EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);

	eventFd2.signal();
	eventFd2.clear();
	EXPECT_EQ(epoll_wait(epollFd.get(), events.data(), events.size(), 0), 0);
	}

	TEST_F(BufferHubBufferTest, ImportFreedBuffer) {
	auto b1 = BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	kUserMetadataSize);
	ASSERT_THAT(b1, NotNull());
	EXPECT_TRUE(b1->IsValid());

	native_handle_t* token = b1->Duplicate();
	EXPECT_TRUE(token);

	// Explicitly destroy b1. Backend buffer should be freed and token becomes invalid
	b1.reset();

	// TODO(b/122543147): use a movalbe wrapper for token
	std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
	native_handle_close(token);
	native_handle_delete(token);

	// Import should fail with INVALID_TOKEN
	EXPECT_THAT(b2, IsNull());
	}

	// nullptr must not crash the service
	TEST_F(BufferHubBufferTest, ImportNullToken) {
	auto b1 = BufferHubBuffer::Import(nullptr);
	EXPECT_THAT(b1, IsNull());
	}

	TEST_F(BufferHubBufferTest, ImportInvalidToken) {
	native_handle_t* token = native_handle_create(/numFds=/0, /numInts=/1);
	token->data[0] = 0;

	auto b1 = BufferHubBuffer::Import(token);
	native_handle_delete(token);

	EXPECT_THAT(b1, IsNull());
	}

	TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromReleasedState) {
	ASSERT_TRUE(b1->IsReleased());

	// Successful gaining the buffer should change the buffer state bit of b1 to
	// gained state, other client state bits to released state.
	EXPECT_EQ(b1->Gain(), 0);
	EXPECT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));
	}

	TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromGainedState) {
	ASSERT_EQ(b1->Gain(), 0);
	auto current_buffer_state = b1->buffer_state();
	ASSERT_TRUE(IsClientGained(current_buffer_state, b1ClientMask));

	// Gaining from gained state by the same client should not return error.
	EXPECT_EQ(b1->Gain(), 0);

	// Gaining from gained state by another client should return error.
	EXPECT_EQ(b2->Gain(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromAcquiredState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_EQ(b2->Acquire(), 0);
	ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

	// Gaining from acquired state should fail.
	EXPECT_EQ(b1->Gain(), -EBUSY);
	EXPECT_EQ(b2->Gain(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromOtherClientInPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

	// Gaining a buffer who has other posted client should succeed.
	EXPECT_EQ(b1->Gain(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, GainBuffer_fromSelfInPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

	// A posted client should be able to gain the buffer when there is no other clients in
	// acquired state.
	EXPECT_EQ(b2->Gain(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromOtherInGainedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));

	EXPECT_EQ(b2->Post(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromSelfInGainedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_TRUE(IsClientGained(b1->buffer_state(), b1ClientMask));

	EXPECT_EQ(b1->Post(), 0);
	auto current_buffer_state = b1->buffer_state();
	EXPECT_TRUE(IsClientReleased(current_buffer_state, b1ClientMask));
	EXPECT_TRUE(IsClientPosted(current_buffer_state, b2ClientMask));
	}

	TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

	// Post from posted state should fail.
	EXPECT_EQ(b1->Post(), -EBUSY);
	EXPECT_EQ(b2->Post(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromAcquiredState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_EQ(b2->Acquire(), 0);
	ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

	// Posting from acquired state should fail.
	EXPECT_EQ(b1->Post(), -EBUSY);
	EXPECT_EQ(b2->Post(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, PostBuffer_fromReleasedState) {
	ASSERT_TRUE(b1->IsReleased());

	// Posting from released state should fail.
	EXPECT_EQ(b1->Post(), -EBUSY);
	EXPECT_EQ(b2->Post(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromSelfInPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(IsClientPosted(b1->buffer_state(), b2ClientMask));

	// Acquire from posted state should pass.
	EXPECT_EQ(b2->Acquire(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromOtherInPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(IsClientPosted(b1->buffer_state(), b2ClientMask));

	// Acquire from released state should fail, although there are other clients
	// in posted state.
	EXPECT_EQ(b1->Acquire(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromSelfInAcquiredState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_EQ(b2->Acquire(), 0);
	auto current_buffer_state = b1->buffer_state();
	ASSERT_TRUE(IsClientAcquired(current_buffer_state, b2ClientMask));

	// Acquiring from acquired state by the same client should not error out.
	EXPECT_EQ(b2->Acquire(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromReleasedState) {
	ASSERT_TRUE(b1->IsReleased());

	// Acquiring form released state should fail.
	EXPECT_EQ(b1->Acquire(), -EBUSY);
	EXPECT_EQ(b2->Acquire(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, AcquireBuffer_fromGainedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_TRUE(AnyClientGained(b1->buffer_state()));

	// Acquiring from gained state should fail.
	EXPECT_EQ(b1->Acquire(), -EBUSY);
	EXPECT_EQ(b2->Acquire(), -EBUSY);
	}

	TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInReleasedState) {
	ASSERT_TRUE(b1->IsReleased());

	EXPECT_EQ(b1->Release(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInGainedState) {
	ASSERT_TRUE(b1->IsReleased());
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_TRUE(AnyClientGained(b1->buffer_state()));

	EXPECT_EQ(b1->Release(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInPostedState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_TRUE(AnyClientPosted(b1->buffer_state()));

	EXPECT_EQ(b2->Release(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, ReleaseBuffer_fromSelfInAcquiredState) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_EQ(b2->Acquire(), 0);
	ASSERT_TRUE(AnyClientAcquired(b1->buffer_state()));

	EXPECT_EQ(b2->Release(), 0);
	}

	TEST_F(BufferHubBufferStateTransitionTest, BasicUsage) {
	// 1 producer buffer and 1 consumer buffer initialised in testcase setup.
	// Test if this set of basic operation succeed:
	// Producer post three times to the consumer, and released by consumer.
	for (int i = 0; i < 3; ++i) {
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);
	ASSERT_EQ(b2->Acquire(), 0);
	ASSERT_EQ(b2->Release(), 0);
	}
	}

	TEST_F(BufferHubBufferTest, createNewConsumerAfterGain) {
	// Create a poducer buffer and gain.
	std::unique_ptr<BufferHubBuffer> b1 =
	BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	kUserMetadataSize);
	ASSERT_THAT(b1, NotNull());
	ASSERT_EQ(b1->Gain(), 0);

	// Create a consumer of the buffer and test if the consumer can acquire the
	// buffer if producer posts.
	// TODO(b/122543147): use a movalbe wrapper for token
	native_handle_t* token = b1->Duplicate();
	ASSERT_TRUE(token);

	std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
	native_handle_close(token);
	native_handle_delete(token);

	ASSERT_THAT(b2, NotNull());
	ASSERT_NE(b1->client_state_mask(), b2->client_state_mask());

	ASSERT_EQ(b1->Post(), 0);
	EXPECT_EQ(b2->Acquire(), 0);
	}

	TEST_F(BufferHubBufferTest, createNewConsumerAfterPost) {
	// Create a poducer buffer and post.
	std::unique_ptr<BufferHubBuffer> b1 =
	BufferHubBuffer::Create(kWidth, kHeight, kLayerCount, kFormat, kUsage,
	kUserMetadataSize);
	ASSERT_EQ(b1->Gain(), 0);
	ASSERT_EQ(b1->Post(), 0);

	// Create a consumer of the buffer and test if the consumer can acquire the
	// buffer if producer posts.
	// TODO(b/122543147): use a movalbe wrapper for token
	native_handle_t* token = b1->Duplicate();
	ASSERT_TRUE(token);

	std::unique_ptr<BufferHubBuffer> b2 = BufferHubBuffer::Import(token);
	native_handle_close(token);
	native_handle_delete(token);

	ASSERT_THAT(b2, NotNull());
	ASSERT_NE(b1->client_state_mask(), b2->client_state_mask());

	EXPECT_EQ(b2->Acquire(), 0);
	}

	} // namespace

	} // namespace android