mojo/edk/system/shared_buffer_dispatcher_unittest.cc - mojo-tools - Git at Google

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "mojo/edk/system/shared_buffer_dispatcher.h"

 #include <limits>
 #include <memory>

 #include "mojo/edk/embedder/simple_platform_support.h"
 #include "mojo/edk/platform/platform_shared_buffer.h"
 #include "mojo/edk/system/dispatcher.h"
 #include "mojo/public/cpp/system/macros.h"
 #include "testing/gtest/include/gtest/gtest.h"

 using mojo::platform::PlatformSharedBufferMapping;
 using mojo::util::RefPtr;

 namespace mojo {
 namespace system {
 namespace {

 // NOTE(vtl): There's currently not much to test for in
 // |SharedBufferDispatcher::ValidateCreateOptions()|, but the tests should be
 // expanded if/when options are added, so I've kept the general form of the
 // tests from data_pipe_unittest.cc.

 const uint32_t kSizeOfCreateOptions = sizeof(MojoCreateSharedBufferOptions);

 // Does a cursory sanity check of |validated_options|. Calls
 // |ValidateCreateOptions()| on already-validated options. The validated options
 // should be valid, and the revalidated copy should be the same.
 void RevalidateCreateOptions(
     const MojoCreateSharedBufferOptions& validated_options) {
   EXPECT_EQ(kSizeOfCreateOptions, validated_options.struct_size);
   // Nothing to check for flags.

   MojoCreateSharedBufferOptions revalidated_options = {};
   EXPECT_EQ(MOJO_RESULT_OK,
             SharedBufferDispatcher::ValidateCreateOptions(
                 MakeUserPointer(&validated_options), &revalidated_options));
   EXPECT_EQ(validated_options.struct_size, revalidated_options.struct_size);
   EXPECT_EQ(validated_options.flags, revalidated_options.flags);
 }

 class SharedBufferDispatcherTest : public testing::Test {
  public:
   SharedBufferDispatcherTest()
       : platform_support_(embedder::CreateSimplePlatformSupport()) {}
   ~SharedBufferDispatcherTest() override {}

   embedder::PlatformSupport* platform_support() {
     return platform_support_.get();
   }

  private:
   std::unique_ptr<embedder::PlatformSupport> platform_support_;

   MOJO_DISALLOW_COPY_AND_ASSIGN(SharedBufferDispatcherTest);
 };

 // Tests valid inputs to |ValidateCreateOptions()|.
 TEST_F(SharedBufferDispatcherTest, ValidateCreateOptionsValid) {
   // Default options.
   {
     MojoCreateSharedBufferOptions validated_options = {};
     EXPECT_EQ(MOJO_RESULT_OK, SharedBufferDispatcher::ValidateCreateOptions(
                                   NullUserPointer(), &validated_options));
     RevalidateCreateOptions(validated_options);
   }

   // Different flags.
   MojoCreateSharedBufferOptionsFlags flags_values[] = {
       MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE};
   for (size_t i = 0; i < MOJO_ARRAYSIZE(flags_values); i++) {
     const MojoCreateSharedBufferOptionsFlags flags = flags_values[i];

     // Different capacities (size 1).
     for (uint32_t capacity = 1; capacity <= 100 * 1000 * 1000; capacity *= 10) {
       MojoCreateSharedBufferOptions options = {
           kSizeOfCreateOptions,  // |struct_size|.
           flags                  // |flags|.
       };
       MojoCreateSharedBufferOptions validated_options = {};
       EXPECT_EQ(MOJO_RESULT_OK,
                 SharedBufferDispatcher::ValidateCreateOptions(
                     MakeUserPointer(&options), &validated_options))
           << capacity;
       RevalidateCreateOptions(validated_options);
       EXPECT_EQ(options.flags, validated_options.flags);
     }
   }
 }

 TEST_F(SharedBufferDispatcherTest, ValidateCreateOptionsInvalid) {
   // Invalid |struct_size|.
   {
     MojoCreateSharedBufferOptions options = {
         1,                                           // |struct_size|.
         MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE  // |flags|.
     };
     MojoCreateSharedBufferOptions unused;
     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
               SharedBufferDispatcher::ValidateCreateOptions(
                   MakeUserPointer(&options), &unused));
   }

   // Unknown |flags|.
   {
     MojoCreateSharedBufferOptions options = {
         kSizeOfCreateOptions,  // |struct_size|.
         ~0u                    // |flags|.
     };
     MojoCreateSharedBufferOptions unused;
     EXPECT_EQ(MOJO_RESULT_UNIMPLEMENTED,
               SharedBufferDispatcher::ValidateCreateOptions(
                   MakeUserPointer(&options), &unused));
   }
 }

 TEST_F(SharedBufferDispatcherTest, CreateAndMapBuffer) {
   const uint64_t kSize = 100u;

   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   ASSERT_TRUE(dispatcher);
   EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher->GetType());

   // Get information about the buffer (in particular the size) and check it.
   MojoBufferInformation info = {};
   EXPECT_EQ(MOJO_RESULT_OK,
             dispatcher->GetBufferInformation(
                 MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
   EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
   EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
   EXPECT_EQ(kSize, info.num_bytes);

   // Also check that some invalid calls to |GetBufferInformation()| fail in the
   // expected way.
   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
             dispatcher->GetBufferInformation(MakeUserPointer(&info), 0u));
   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
             dispatcher->GetBufferInformation(MakeUserPointer(&info), 15u));

   // It's also valid to call it with a larger-than-required |info_num_bytes|.
   // (Note: The pointer must be aligned, so we use an array of two
   // |MojoBufferInformation|s.)
   MojoBufferInformation infos[2] = {};
   EXPECT_EQ(MOJO_RESULT_OK, dispatcher->GetBufferInformation(
                                 MakeUserPointer(&infos[0]),
                                 static_cast<uint32_t>(sizeof(infos[0]) + 1)));
   EXPECT_EQ(kSize, infos[0].num_bytes);

   // Make a couple of mappings.
   std::unique_ptr<PlatformSharedBufferMapping> mapping1;
   EXPECT_EQ(
       MOJO_RESULT_OK,
       dispatcher->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping1));
   ASSERT_TRUE(mapping1);
   ASSERT_TRUE(mapping1->GetBase());
   EXPECT_EQ(kSize, mapping1->GetLength());
   // Write something.
   static_cast<char*>(mapping1->GetBase())[50] = 'x';

   std::unique_ptr<PlatformSharedBufferMapping> mapping2;
   EXPECT_EQ(MOJO_RESULT_OK,
             dispatcher->MapBuffer(kSize / 2, kSize / 2,
                                   MOJO_MAP_BUFFER_FLAG_NONE, &mapping2));
   ASSERT_TRUE(mapping2);
   ASSERT_TRUE(mapping2->GetBase());
   EXPECT_EQ(kSize / 2, mapping2->GetLength());
   EXPECT_EQ('x', static_cast<char*>(mapping2->GetBase())[0]);

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher->Close());

   // Check that we can still read/write to mappings after the dispatcher has
   // gone away.
   static_cast<char*>(mapping2->GetBase())[1] = 'y';
   EXPECT_EQ('y', static_cast<char*>(mapping1->GetBase())[kSize / 2 + 1]);
 }

 TEST_F(SharedBufferDispatcherTest, SupportsEntrypointClass) {
   MojoResult result = MOJO_RESULT_INTERNAL;
   auto d = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100u,
       &result);
   ASSERT_TRUE(d);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   EXPECT_TRUE(d->SupportsEntrypointClass(EntrypointClass::NONE));
   EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::MESSAGE_PIPE));
   EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::DATA_PIPE_PRODUCER));
   EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::DATA_PIPE_CONSUMER));
   EXPECT_TRUE(d->SupportsEntrypointClass(EntrypointClass::BUFFER));

   // TODO(vtl): Check that it actually returns |MOJO_RESULT_INVALID_ARGUMENT|
   // for methods in unsupported entrypoint classes.

   EXPECT_EQ(MOJO_RESULT_OK, d->Close());
 }

 TEST_F(SharedBufferDispatcherTest, DuplicateDispatcher) {
   const uint64_t kSize = 100u;

   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher1 = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   // Map and write something.
   std::unique_ptr<PlatformSharedBufferMapping> mapping;
   EXPECT_EQ(
       MOJO_RESULT_OK,
       dispatcher1->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   static_cast<char*>(mapping->GetBase())[0] = 'x';
   mapping.reset();

   // Duplicate |dispatcher1| and then close it.
   RefPtr<Dispatcher> dispatcher2;
   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateDispatcher(&dispatcher2));
   ASSERT_TRUE(dispatcher2);
   EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());

   // Make sure that |dispatcher2| still reports the right information.
   MojoBufferInformation info = {};
   EXPECT_EQ(MOJO_RESULT_OK,
             dispatcher2->GetBufferInformation(
                 MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
   EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
   EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
   EXPECT_EQ(kSize, info.num_bytes);

   // Map |dispatcher2| and read something.
   EXPECT_EQ(
       MOJO_RESULT_OK,
       dispatcher2->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   EXPECT_EQ('x', static_cast<char*>(mapping->GetBase())[0]);

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
 }

 TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandle) {
   const uint64_t kSize = 100u;

   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher1 = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   // Map and write something.
   std::unique_ptr<PlatformSharedBufferMapping> mapping;
   EXPECT_EQ(
       MOJO_RESULT_OK,
       dispatcher1->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   static_cast<char*>(mapping->GetBase())[0] = 'x';
   mapping.reset();

   // Duplicate |dispatcher1| and then close it.
   RefPtr<Dispatcher> dispatcher2;
   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateBufferHandle(
                                 NullUserPointer(), &dispatcher2));
   ASSERT_TRUE(dispatcher2);
   EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());

   // Make sure that |dispatcher2| still reports the right information.
   MojoBufferInformation info = {};
   EXPECT_EQ(MOJO_RESULT_OK,
             dispatcher2->GetBufferInformation(
                 MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
   EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
   EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
   EXPECT_EQ(kSize, info.num_bytes);

   // Map |dispatcher2| and read something.
   EXPECT_EQ(
       MOJO_RESULT_OK,
       dispatcher2->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   EXPECT_EQ('x', static_cast<char*>(mapping->GetBase())[0]);

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
 }

 TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandleOptionsValid) {
   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher1 = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   MojoDuplicateBufferHandleOptions options[] = {
       {sizeof(MojoDuplicateBufferHandleOptions),
        MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE},
       {sizeof(MojoDuplicateBufferHandleOptionsFlags), ~0u}};
   for (size_t i = 0; i < MOJO_ARRAYSIZE(options); i++) {
     RefPtr<Dispatcher> dispatcher2;
     EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateBufferHandle(
                                   MakeUserPointer(&options[i]), &dispatcher2));
     ASSERT_TRUE(dispatcher2);
     EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());
     EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
   }

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());
 }

 TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandleOptionsInvalid) {
   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher1 = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   // Invalid |struct_size|.
   {
     MojoDuplicateBufferHandleOptions options = {
         1u, MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE};
     RefPtr<Dispatcher> dispatcher2;
     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
               dispatcher1->DuplicateBufferHandle(MakeUserPointer(&options),
                                                  &dispatcher2));
     EXPECT_FALSE(dispatcher2);
   }

   // Unknown |flags|.
   {
     MojoDuplicateBufferHandleOptions options = {
         sizeof(MojoDuplicateBufferHandleOptions), ~0u};
     RefPtr<Dispatcher> dispatcher2;
     EXPECT_EQ(MOJO_RESULT_UNIMPLEMENTED,
               dispatcher1->DuplicateBufferHandle(MakeUserPointer(&options),
                                                  &dispatcher2));
     EXPECT_FALSE(dispatcher2);
   }

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());
 }

 TEST_F(SharedBufferDispatcherTest, CreateInvalidNumBytes) {
   // Size too big.
   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions,
       std::numeric_limits<uint64_t>::max(), &result);
   EXPECT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED, result);
   EXPECT_FALSE(dispatcher);

   // Zero size.
   result = MOJO_RESULT_INTERNAL;
   dispatcher = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 0,
       &result);
   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, result);
   EXPECT_FALSE(dispatcher);
 }

 TEST_F(SharedBufferDispatcherTest, MapBufferInvalidArguments) {
   MojoResult result = MOJO_RESULT_INTERNAL;
   auto dispatcher = SharedBufferDispatcher::Create(
       platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
       &result);
   EXPECT_EQ(MOJO_RESULT_OK, result);

   std::unique_ptr<PlatformSharedBufferMapping> mapping;
   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
             dispatcher->MapBuffer(0, 101, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   EXPECT_FALSE(mapping);

   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
             dispatcher->MapBuffer(1, 100, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   EXPECT_FALSE(mapping);

   EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
             dispatcher->MapBuffer(0, 0, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
   EXPECT_FALSE(mapping);

   EXPECT_EQ(MOJO_RESULT_OK, dispatcher->Close());
 }

 }  // namespace
 }  // namespace system
 }  // namespace mojo
	// Copyright 2014 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "mojo/edk/system/shared_buffer_dispatcher.h"

	#include <limits>
	#include <memory>

	#include "mojo/edk/embedder/simple_platform_support.h"
	#include "mojo/edk/platform/platform_shared_buffer.h"
	#include "mojo/edk/system/dispatcher.h"
	#include "mojo/public/cpp/system/macros.h"
	#include "testing/gtest/include/gtest/gtest.h"

	using mojo::platform::PlatformSharedBufferMapping;
	using mojo::util::RefPtr;

	namespace mojo {
	namespace system {
	namespace {

	// NOTE(vtl): There's currently not much to test for in
	// \|SharedBufferDispatcher::ValidateCreateOptions()\|, but the tests should be
	// expanded if/when options are added, so I've kept the general form of the
	// tests from data_pipe_unittest.cc.

	const uint32_t kSizeOfCreateOptions = sizeof(MojoCreateSharedBufferOptions);

	// Does a cursory sanity check of \|validated_options\|. Calls
	// \|ValidateCreateOptions()\| on already-validated options. The validated options
	// should be valid, and the revalidated copy should be the same.
	void RevalidateCreateOptions(
	const MojoCreateSharedBufferOptions& validated_options) {
	EXPECT_EQ(kSizeOfCreateOptions, validated_options.struct_size);
	// Nothing to check for flags.

	MojoCreateSharedBufferOptions revalidated_options = {};
	EXPECT_EQ(MOJO_RESULT_OK,
	SharedBufferDispatcher::ValidateCreateOptions(
	MakeUserPointer(&validated_options), &revalidated_options));
	EXPECT_EQ(validated_options.struct_size, revalidated_options.struct_size);
	EXPECT_EQ(validated_options.flags, revalidated_options.flags);
	}

	class SharedBufferDispatcherTest : public testing::Test {
	public:
	SharedBufferDispatcherTest()
	: platform_support_(embedder::CreateSimplePlatformSupport()) {}
	~SharedBufferDispatcherTest() override {}

	embedder::PlatformSupport* platform_support() {
	return platform_support_.get();
	}

	private:
	std::unique_ptr<embedder::PlatformSupport> platform_support_;

	MOJO_DISALLOW_COPY_AND_ASSIGN(SharedBufferDispatcherTest);
	};

	// Tests valid inputs to \|ValidateCreateOptions()\|.
	TEST_F(SharedBufferDispatcherTest, ValidateCreateOptionsValid) {
	// Default options.
	{
	MojoCreateSharedBufferOptions validated_options = {};
	EXPECT_EQ(MOJO_RESULT_OK, SharedBufferDispatcher::ValidateCreateOptions(
	NullUserPointer(), &validated_options));
	RevalidateCreateOptions(validated_options);
	}

	// Different flags.
	MojoCreateSharedBufferOptionsFlags flags_values[] = {
	MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE};
	for (size_t i = 0; i < MOJO_ARRAYSIZE(flags_values); i++) {
	const MojoCreateSharedBufferOptionsFlags flags = flags_values[i];

	// Different capacities (size 1).
	for (uint32_t capacity = 1; capacity <= 100 * 1000 * 1000; capacity *= 10) {
	MojoCreateSharedBufferOptions options = {
	kSizeOfCreateOptions, // \|struct_size\|.
	flags // \|flags\|.
	};
	MojoCreateSharedBufferOptions validated_options = {};
	EXPECT_EQ(MOJO_RESULT_OK,
	SharedBufferDispatcher::ValidateCreateOptions(
	MakeUserPointer(&options), &validated_options))
	<< capacity;
	RevalidateCreateOptions(validated_options);
	EXPECT_EQ(options.flags, validated_options.flags);
	}
	}
	}

	TEST_F(SharedBufferDispatcherTest, ValidateCreateOptionsInvalid) {
	// Invalid \|struct_size\|.
	{
	MojoCreateSharedBufferOptions options = {
	1, // \|struct_size\|.
	MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE // \|flags\|.
	};
	MojoCreateSharedBufferOptions unused;
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	SharedBufferDispatcher::ValidateCreateOptions(
	MakeUserPointer(&options), &unused));
	}

	// Unknown \|flags\|.
	{
	MojoCreateSharedBufferOptions options = {
	kSizeOfCreateOptions, // \|struct_size\|.
	~0u // \|flags\|.
	};
	MojoCreateSharedBufferOptions unused;
	EXPECT_EQ(MOJO_RESULT_UNIMPLEMENTED,
	SharedBufferDispatcher::ValidateCreateOptions(
	MakeUserPointer(&options), &unused));
	}
	}

	TEST_F(SharedBufferDispatcherTest, CreateAndMapBuffer) {
	const uint64_t kSize = 100u;

	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	ASSERT_TRUE(dispatcher);
	EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher->GetType());

	// Get information about the buffer (in particular the size) and check it.
	MojoBufferInformation info = {};
	EXPECT_EQ(MOJO_RESULT_OK,
	dispatcher->GetBufferInformation(
	MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
	EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
	EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
	EXPECT_EQ(kSize, info.num_bytes);

	// Also check that some invalid calls to \|GetBufferInformation()\| fail in the
	// expected way.
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher->GetBufferInformation(MakeUserPointer(&info), 0u));
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher->GetBufferInformation(MakeUserPointer(&info), 15u));

	// It's also valid to call it with a larger-than-required \|info_num_bytes\|.
	// (Note: The pointer must be aligned, so we use an array of two
	// \|MojoBufferInformation\|s.)
	MojoBufferInformation infos[2] = {};
	EXPECT_EQ(MOJO_RESULT_OK, dispatcher->GetBufferInformation(
	MakeUserPointer(&infos[0]),
	static_cast<uint32_t>(sizeof(infos[0]) + 1)));
	EXPECT_EQ(kSize, infos[0].num_bytes);

	// Make a couple of mappings.
	std::unique_ptr<PlatformSharedBufferMapping> mapping1;
	EXPECT_EQ(
	MOJO_RESULT_OK,
	dispatcher->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping1));
	ASSERT_TRUE(mapping1);
	ASSERT_TRUE(mapping1->GetBase());
	EXPECT_EQ(kSize, mapping1->GetLength());
	// Write something.
	static_cast<char*>(mapping1->GetBase())[50] = 'x';

	std::unique_ptr<PlatformSharedBufferMapping> mapping2;
	EXPECT_EQ(MOJO_RESULT_OK,
	dispatcher->MapBuffer(kSize / 2, kSize / 2,
	MOJO_MAP_BUFFER_FLAG_NONE, &mapping2));
	ASSERT_TRUE(mapping2);
	ASSERT_TRUE(mapping2->GetBase());
	EXPECT_EQ(kSize / 2, mapping2->GetLength());
	EXPECT_EQ('x', static_cast<char*>(mapping2->GetBase())[0]);

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher->Close());

	// Check that we can still read/write to mappings after the dispatcher has
	// gone away.
	static_cast<char*>(mapping2->GetBase())[1] = 'y';
	EXPECT_EQ('y', static_cast<char*>(mapping1->GetBase())[kSize / 2 + 1]);
	}

	TEST_F(SharedBufferDispatcherTest, SupportsEntrypointClass) {
	MojoResult result = MOJO_RESULT_INTERNAL;
	auto d = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100u,
	&result);
	ASSERT_TRUE(d);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	EXPECT_TRUE(d->SupportsEntrypointClass(EntrypointClass::NONE));
	EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::MESSAGE_PIPE));
	EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::DATA_PIPE_PRODUCER));
	EXPECT_FALSE(d->SupportsEntrypointClass(EntrypointClass::DATA_PIPE_CONSUMER));
	EXPECT_TRUE(d->SupportsEntrypointClass(EntrypointClass::BUFFER));

	// TODO(vtl): Check that it actually returns \|MOJO_RESULT_INVALID_ARGUMENT\|
	// for methods in unsupported entrypoint classes.

	EXPECT_EQ(MOJO_RESULT_OK, d->Close());
	}

	TEST_F(SharedBufferDispatcherTest, DuplicateDispatcher) {
	const uint64_t kSize = 100u;

	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher1 = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	// Map and write something.
	std::unique_ptr<PlatformSharedBufferMapping> mapping;
	EXPECT_EQ(
	MOJO_RESULT_OK,
	dispatcher1->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	static_cast<char*>(mapping->GetBase())[0] = 'x';
	mapping.reset();

	// Duplicate \|dispatcher1\| and then close it.
	RefPtr<Dispatcher> dispatcher2;
	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateDispatcher(&dispatcher2));
	ASSERT_TRUE(dispatcher2);
	EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());

	// Make sure that \|dispatcher2\| still reports the right information.
	MojoBufferInformation info = {};
	EXPECT_EQ(MOJO_RESULT_OK,
	dispatcher2->GetBufferInformation(
	MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
	EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
	EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
	EXPECT_EQ(kSize, info.num_bytes);

	// Map \|dispatcher2\| and read something.
	EXPECT_EQ(
	MOJO_RESULT_OK,
	dispatcher2->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	EXPECT_EQ('x', static_cast<char*>(mapping->GetBase())[0]);

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
	}

	TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandle) {
	const uint64_t kSize = 100u;

	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher1 = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, kSize,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	// Map and write something.
	std::unique_ptr<PlatformSharedBufferMapping> mapping;
	EXPECT_EQ(
	MOJO_RESULT_OK,
	dispatcher1->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	static_cast<char*>(mapping->GetBase())[0] = 'x';
	mapping.reset();

	// Duplicate \|dispatcher1\| and then close it.
	RefPtr<Dispatcher> dispatcher2;
	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateBufferHandle(
	NullUserPointer(), &dispatcher2));
	ASSERT_TRUE(dispatcher2);
	EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());

	// Make sure that \|dispatcher2\| still reports the right information.
	MojoBufferInformation info = {};
	EXPECT_EQ(MOJO_RESULT_OK,
	dispatcher2->GetBufferInformation(
	MakeUserPointer(&info), static_cast<uint32_t>(sizeof(info))));
	EXPECT_EQ(sizeof(MojoBufferInformation), info.struct_size);
	EXPECT_EQ(MOJO_BUFFER_INFORMATION_FLAG_NONE, info.flags);
	EXPECT_EQ(kSize, info.num_bytes);

	// Map \|dispatcher2\| and read something.
	EXPECT_EQ(
	MOJO_RESULT_OK,
	dispatcher2->MapBuffer(0u, kSize, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	EXPECT_EQ('x', static_cast<char*>(mapping->GetBase())[0]);

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
	}

	TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandleOptionsValid) {
	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher1 = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	MojoDuplicateBufferHandleOptions options[] = {
	{sizeof(MojoDuplicateBufferHandleOptions),
	MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE},
	{sizeof(MojoDuplicateBufferHandleOptionsFlags), ~0u}};
	for (size_t i = 0; i < MOJO_ARRAYSIZE(options); i++) {
	RefPtr<Dispatcher> dispatcher2;
	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->DuplicateBufferHandle(
	MakeUserPointer(&options[i]), &dispatcher2));
	ASSERT_TRUE(dispatcher2);
	EXPECT_EQ(Dispatcher::Type::SHARED_BUFFER, dispatcher2->GetType());
	EXPECT_EQ(MOJO_RESULT_OK, dispatcher2->Close());
	}

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());
	}

	TEST_F(SharedBufferDispatcherTest, DuplicateBufferHandleOptionsInvalid) {
	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher1 = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	// Invalid \|struct_size\|.
	{
	MojoDuplicateBufferHandleOptions options = {
	1u, MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE};
	RefPtr<Dispatcher> dispatcher2;
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher1->DuplicateBufferHandle(MakeUserPointer(&options),
	&dispatcher2));
	EXPECT_FALSE(dispatcher2);
	}

	// Unknown \|flags\|.
	{
	MojoDuplicateBufferHandleOptions options = {
	sizeof(MojoDuplicateBufferHandleOptions), ~0u};
	RefPtr<Dispatcher> dispatcher2;
	EXPECT_EQ(MOJO_RESULT_UNIMPLEMENTED,
	dispatcher1->DuplicateBufferHandle(MakeUserPointer(&options),
	&dispatcher2));
	EXPECT_FALSE(dispatcher2);
	}

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher1->Close());
	}

	TEST_F(SharedBufferDispatcherTest, CreateInvalidNumBytes) {
	// Size too big.
	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions,
	std::numeric_limits<uint64_t>::max(), &result);
	EXPECT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED, result);
	EXPECT_FALSE(dispatcher);

	// Zero size.
	result = MOJO_RESULT_INTERNAL;
	dispatcher = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 0,
	&result);
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, result);
	EXPECT_FALSE(dispatcher);
	}

	TEST_F(SharedBufferDispatcherTest, MapBufferInvalidArguments) {
	MojoResult result = MOJO_RESULT_INTERNAL;
	auto dispatcher = SharedBufferDispatcher::Create(
	platform_support(), SharedBufferDispatcher::kDefaultCreateOptions, 100,
	&result);
	EXPECT_EQ(MOJO_RESULT_OK, result);

	std::unique_ptr<PlatformSharedBufferMapping> mapping;
	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher->MapBuffer(0, 101, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	EXPECT_FALSE(mapping);

	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher->MapBuffer(1, 100, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	EXPECT_FALSE(mapping);

	EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
	dispatcher->MapBuffer(0, 0, MOJO_MAP_BUFFER_FLAG_NONE, &mapping));
	EXPECT_FALSE(mapping);

	EXPECT_EQ(MOJO_RESULT_OK, dispatcher->Close());
	}

	} // namespace
	} // namespace system
	} // namespace mojo