Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

mojo/edk/system/multiprocess_message_pipe_unittest.cc

+// Copyright 2013 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 <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/files/scoped_file.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/test/test_io_thread.h"
+#include "build/build_config.h"  // TODO(vtl): Remove this.
+#include "mojo/edk/embedder/embedder.h"
+#include "mojo/edk/embedder/platform_channel_pair.h"
+#include "mojo/edk/embedder/platform_shared_buffer.h"
+#include "mojo/edk/embedder/scoped_platform_handle.h"
+#include "mojo/edk/system/dispatcher.h"
+#include "mojo/edk/system/message_pipe_test_utils.h"
+#include "mojo/edk/system/platform_handle_dispatcher.h"
+#include "mojo/edk/system/raw_channel.h"
+#include "mojo/edk/system/shared_buffer_dispatcher.h"
+#include "mojo/edk/system/test_utils.h"
+#include "mojo/edk/test/test_utils.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+
+namespace mojo {
+namespace edk {
+namespace {
+
+class MultiprocessMessagePipeTest
+    : public test::MultiprocessMessagePipeTestBase {};
+
+// For each message received, sends a reply message with the same contents
+// repeated twice, until the other end is closed or it receives "quitquitquit"
+// (which it doesn't reply to). It'll return the number of messages received,
+// not including any "quitquitquit" message, modulo 100.
+MOJO_MULTIPROCESS_TEST_CHILD_MAIN(EchoEcho) {
+  SimplePlatformSupport platform_support;
+  base::MessageLoop message_loop;
+  base::TestIOThread test_io_thread(base::TestIOThread::kAutoStart);
+  test::ScopedIPCSupport ipc_support(test_io_thread.task_runner());
+
+  ScopedPlatformHandle client_platform_handle =
+      test::MultiprocessTestHelper::client_platform_handle.Pass();
+  CHECK(client_platform_handle.is_valid());
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(client_platform_handle.Pass());
+
+  const std::string quitquitquit("quitquitquit");
+  int rv = 0;
+  for (;; rv = (rv + 1) % 100) {
+    // Wait for our end of the message pipe to be readable.
+    HandleSignalsState hss;
+    MojoResult result =
+        MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                 MOJO_DEADLINE_INDEFINITE, &hss);
+    if (result != MOJO_RESULT_OK) {
+      // It was closed, probably.
+      CHECK_EQ(result, MOJO_RESULT_FAILED_PRECONDITION);
+      CHECK_EQ(hss.satisfied_signals, MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+      CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+      break;
+    } else {
+      CHECK((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+      CHECK((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+    }
+
+    std::string read_buffer(1000, '\0');
+    uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+    CHECK_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0],
+                             &read_buffer_size, nullptr,
+                             0, MOJO_READ_MESSAGE_FLAG_NONE),
+             MOJO_RESULT_OK);
+    read_buffer.resize(read_buffer_size);
+    VLOG(2) << "Child got: " << read_buffer;
+
+    if (read_buffer == quitquitquit) {
+      VLOG(2) << "Child quitting.";
+      break;
+    }
+
+    std::string write_buffer = read_buffer + read_buffer;
+    CHECK_EQ(MojoWriteMessage(mp.get().value(), write_buffer.data(),
+                              write_buffer.size(),
+                              nullptr, 0, MOJO_WRITE_MESSAGE_FLAG_NONE),
+             MOJO_RESULT_OK);
+  }
+
+   return rv;
+}
+
+// Sends "hello" to child, and expects "hellohello" back.
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_Basic DISABLED_Basic
+#else
+#define MAYBE_Basic Basic
+#endif  // defined(OS_ANDROID)
+TEST_F(MultiprocessMessagePipeTest, MAYBE_Basic) {
+  helper()->StartChild("EchoEcho");
+
+  ScopedMessagePipeHandle mp = CreateMessagePipe(
+      helper()->server_platform_handle.Pass());
+
+  std::string hello("hello");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), hello.data(),
+                             hello.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss));
+  // The child may or may not have closed its end of the message pipe and died
+  // (and we may or may not know it yet), so our end may or may not appear as
+  // writable.
+  EXPECT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+  EXPECT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+  std::string read_buffer(1000, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0],
+                           &read_buffer_size, nullptr, 0,
+                           MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  VLOG(2) << "Parent got: " << read_buffer;
+  ASSERT_EQ(hello + hello, read_buffer);
+
+  MojoClose(mp.release().value());
+
+  // We sent one message.
+  ASSERT_EQ(1 % 100, helper()->WaitForChildShutdown());
+}
+
+// Sends a bunch of messages to the child. Expects them "repeated" back. Waits
+// for the child to close its end before quitting.
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_QueueMessages DISABLED_QueueMessages
+#else
+#define MAYBE_QueueMessages QueueMessages
+#endif  // defined(OS_ANDROID)
+TEST_F(MultiprocessMessagePipeTest, MAYBE_QueueMessages) {
+  helper()->StartChild("EchoEcho");
+
+  ScopedMessagePipeHandle mp = CreateMessagePipe(
+      helper()->server_platform_handle.Pass());
+
+  static const size_t kNumMessages = 1001;
+  for (size_t i = 0; i < kNumMessages; i++) {
+    std::string write_buffer(i, 'A' + (i % 26));
+    ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), write_buffer.data(),
+                             write_buffer.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+  }
+
+  const std::string quitquitquit("quitquitquit");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), quitquitquit.data(),
+                             quitquitquit.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  for (size_t i = 0; i < kNumMessages; i++) {
+    HandleSignalsState hss;
+    ASSERT_EQ(MOJO_RESULT_OK,
+              MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                       MOJO_DEADLINE_INDEFINITE, &hss));
+    // The child may or may not have closed its end of the message pipe and died
+    // (and we may or may not know it yet), so our end may or may not appear as
+    // writable.
+    ASSERT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+    ASSERT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+    std::string read_buffer(kNumMessages * 2, '\0');
+    uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+    ASSERT_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0],
+                             &read_buffer_size, nullptr, 0,
+                             MOJO_READ_MESSAGE_FLAG_NONE),
+             MOJO_RESULT_OK);
+    read_buffer.resize(read_buffer_size);
+
+    ASSERT_EQ(std::string(i * 2, 'A' + (i % 26)), read_buffer);
+  }
+
+  // Wait for it to become readable, which should fail (since we sent
+  // "quitquitquit").
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfiable_signals);
+
+  ASSERT_EQ(static_cast<int>(kNumMessages % 100),
+            helper()->WaitForChildShutdown());
+}
+
+MOJO_MULTIPROCESS_TEST_CHILD_MAIN(CheckSharedBuffer) {
+  SimplePlatformSupport platform_support;
+  base::MessageLoop message_loop;
+  base::TestIOThread test_io_thread(base::TestIOThread::kAutoStart);
+  test::ScopedIPCSupport ipc_support(test_io_thread.task_runner());
+
+  ScopedPlatformHandle client_platform_handle =
+      test::MultiprocessTestHelper::client_platform_handle.Pass();
+  CHECK(client_platform_handle.is_valid());
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(client_platform_handle.Pass());
+
+  // Wait for the first message from our parent.
+  HandleSignalsState hss;
+  CHECK_EQ(MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  // In this test, the parent definitely doesn't close its end of the message
+  // pipe before we do.
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                    MOJO_HANDLE_SIGNAL_WRITABLE |
+                                    MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  // It should have a shared buffer.
+  std::string read_buffer(100, '\0');
+  uint32_t num_bytes = static_cast<uint32_t>(read_buffer.size());
+  MojoHandle handles[10];
+  uint32_t num_handlers = MOJO_ARRAYSIZE(handles);  // Maximum number to receive
+  CHECK_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0],
+                           &num_bytes, &handles[0],
+                           &num_handlers, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(num_bytes);
+  CHECK_EQ(read_buffer, std::string("go 1"));
+  CHECK_EQ(num_handlers, 1u);
+
+  // Make a mapping.
+  void* buffer;
+  CHECK_EQ(MojoMapBuffer(handles[0], 0, 100, &buffer,
+                         MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE),
+           MOJO_RESULT_OK);
+
+  // Write some stuff to the shared buffer.
+  static const char kHello[] = "hello";
+  memcpy(buffer, kHello, sizeof(kHello));
+
+  // We should be able to close the dispatcher now.
+  MojoClose(handles[0]);
+
+  // And send a message to signal that we've written stuff.
+  const std::string go2("go 2");
+  CHECK_EQ(MojoWriteMessage(mp.get().value(), go2.data(),
+                              go2.size(), nullptr, 0,
+                              MOJO_WRITE_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+
+  // Now wait for our parent to send us a message.
+  hss = HandleSignalsState();
+  CHECK_EQ(MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                        MOJO_HANDLE_SIGNAL_WRITABLE |
+                                        MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  read_buffer = std::string(100, '\0');
+  num_bytes = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0], &num_bytes,
+                           nullptr, 0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(num_bytes);
+  CHECK_EQ(read_buffer, std::string("go 3"));
+
+  // It should have written something to the shared buffer.
+  static const char kWorld[] = "world!!!";
+  CHECK_EQ(memcmp(buffer, kWorld, sizeof(kWorld)), 0);
+
+  // And we're done.
+
+  return 0;
+}
+
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_SharedBufferPassing DISABLED_SharedBufferPassing
+#else
+#define MAYBE_SharedBufferPassing SharedBufferPassing
+#endif
+TEST_F(MultiprocessMessagePipeTest, MAYBE_SharedBufferPassing) {
+  helper()->StartChild("CheckSharedBuffer");
+
+  ScopedMessagePipeHandle mp = CreateMessagePipe(
+      helper()->server_platform_handle.Pass());
+
+  // Make a shared buffer.
+  MojoCreateSharedBufferOptions options;
+  options.struct_size = sizeof(options);
+  options.flags = MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE;
+
+  MojoHandle shared_buffer;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoCreateSharedBuffer(&options, 100, &shared_buffer));
+
+  // Send the shared buffer.
+  const std::string go1("go 1");
+
+  MojoHandle duplicated_shared_buffer;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoDuplicateBufferHandle(
+                shared_buffer,
+                nullptr,
+                &duplicated_shared_buffer));
+  MojoHandle handles[1];
+  handles[0] = duplicated_shared_buffer;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), &go1[0], go1.size(), &handles[0],
+                             MOJO_ARRAYSIZE(handles),
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for a message from the child.
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  EXPECT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+  EXPECT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+  std::string read_buffer(100, '\0');
+  uint32_t num_bytes = static_cast<uint32_t>(read_buffer.size());
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoReadMessage(mp.get().value(), &read_buffer[0],
+                             &num_bytes, nullptr, 0,
+                             MOJO_READ_MESSAGE_FLAG_NONE));
+  read_buffer.resize(num_bytes);
+  ASSERT_EQ(std::string("go 2"), read_buffer);
+
+  // After we get it, the child should have written something to the shared
+  // buffer.
+  static const char kHello[] = "hello";
+  void* buffer;
+  CHECK_EQ(MojoMapBuffer(shared_buffer, 0, 100, &buffer,
+                         MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE),
+           MOJO_RESULT_OK);
+  ASSERT_EQ(0, memcmp(buffer, kHello, sizeof(kHello)));
+
+  // Now we'll write some stuff to the shared buffer.
+  static const char kWorld[] = "world!!!";
+  memcpy(buffer, kWorld, sizeof(kWorld));
+
+  // And send a message to signal that we've written stuff.
+  const std::string go3("go 3");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), &go3[0],
+                             go3.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for |mp| to become readable, which should fail.
+  hss = HandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfiable_signals);
+
+  MojoClose(mp.release().value());
+
+  ASSERT_EQ(0, helper()->WaitForChildShutdown());
+}
+
+MOJO_MULTIPROCESS_TEST_CHILD_MAIN(CheckPlatformHandleFile) {
+  SimplePlatformSupport platform_support;
+  base::MessageLoop message_loop;
+  base::TestIOThread test_io_thread(base::TestIOThread::kAutoStart);
+  test::ScopedIPCSupport ipc_support(test_io_thread.task_runner());
+
+  ScopedPlatformHandle client_platform_handle =
+      test::MultiprocessTestHelper::client_platform_handle.Pass();
+  CHECK(client_platform_handle.is_valid());
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(client_platform_handle.Pass());
+
+  HandleSignalsState hss;
+  CHECK_EQ(MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                        MOJO_HANDLE_SIGNAL_WRITABLE |
+                                        MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  std::string read_buffer(100, '\0');
+  uint32_t num_bytes = static_cast<uint32_t>(read_buffer.size());
+  MojoHandle handles[255];  // Maximum number to receive.
+  uint32_t num_handlers = MOJO_ARRAYSIZE(handles);
+
+  CHECK_EQ(MojoReadMessage(mp.get().value(), &read_buffer[0],
+                           &num_bytes, &handles[0],
+                           &num_handlers, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  MojoClose(mp.release().value());
+
+  read_buffer.resize(num_bytes);
+  char hello[32];
+  int num_handles = 0;
+  sscanf(read_buffer.c_str(), "%s %d", hello, &num_handles);
+  CHECK_EQ(std::string("hello"), std::string(hello));
+  CHECK_GT(num_handles, 0);
+
+  for (int i = 0; i < num_handles; ++i) {
+    ScopedPlatformHandle h;
+    CHECK_EQ(PassWrappedPlatformHandle(
+                handles[i], &h),
+             MOJO_RESULT_OK);
+    CHECK(h.is_valid());
+    MojoClose(handles[i]);
+
+    base::ScopedFILE fp(test::FILEFromPlatformHandle(h.Pass(), "r"));
+    CHECK(fp);
+    std::string fread_buffer(100, '\0');
+    size_t bytes_read =
+        fread(&fread_buffer[0], 1, fread_buffer.size(), fp.get());
+    fread_buffer.resize(bytes_read);
+    CHECK_EQ(fread_buffer, "world");
+  }
+
+  return 0;
+}
+
+class MultiprocessMessagePipeTestWithPipeCount
+    : public test::MultiprocessMessagePipeTestBase,
+      public testing::WithParamInterface<size_t> {};
+
+TEST_P(MultiprocessMessagePipeTestWithPipeCount, PlatformHandlePassing) {
+  base::ScopedTempDir temp_dir;
+  ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
+
+  helper()->StartChild("CheckPlatformHandleFile");
+  ScopedMessagePipeHandle mp = CreateMessagePipe(
+      helper()->server_platform_handle.Pass());
+
+  std::vector<MojoHandle> handles;
+
+  size_t pipe_count = GetParam();
+  for (size_t i = 0; i < pipe_count; ++i) {
+    base::FilePath unused;
+    base::ScopedFILE fp(
+        CreateAndOpenTemporaryFileInDir(temp_dir.path(), &unused));
+    const std::string world("world");
+    CHECK_EQ(fwrite(&world[0], 1, world.size(), fp.get()), world.size());
+    fflush(fp.get());
+    rewind(fp.get());
+    MojoHandle handle;
+    ASSERT_EQ(CreatePlatformHandleWrapper(
+                  ScopedPlatformHandle(test::PlatformHandleFromFILE(fp.Pass())),
+                  &handle),
+              MOJO_RESULT_OK);
+    handles.push_back(handle);
+  }
+
+  char message[128];
+  sprintf(message, "hello %d", static_cast<int>(pipe_count));
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), message,
+                             strlen(message),
+                             &handles[0], handles.size(),
+                              MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for it to become readable, which should fail.
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfiable_signals);
+
+  MojoClose(mp.release().value());
+
+  ASSERT_EQ(0, helper()->WaitForChildShutdown());
+}
+
+// Android multi-process tests are not executing the new process. This is flaky.
+#if !defined(OS_ANDROID)
+INSTANTIATE_TEST_CASE_P(PipeCount,
+                        MultiprocessMessagePipeTestWithPipeCount,
+                        testing::Values(1u, 128u, 140u));
+#endif
+
+MOJO_MULTIPROCESS_TEST_CHILD_MAIN(CheckMessagePipe) {
+  SimplePlatformSupport platform_support;
+  base::MessageLoop message_loop;
+  base::TestIOThread test_io_thread(base::TestIOThread::kAutoStart);
+  test::ScopedIPCSupport ipc_support(test_io_thread.task_runner());
+
+  ScopedPlatformHandle client_platform_handle =
+      test::MultiprocessTestHelper::client_platform_handle.Pass();
+  CHECK(client_platform_handle.is_valid());
+
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(client_platform_handle.Pass());
+
+  // Wait for the first message from our parent.
+  HandleSignalsState hss;
+  CHECK_EQ(MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  // In this test, the parent definitely doesn't close its end of the message
+  // pipe before we do.
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                    MOJO_HANDLE_SIGNAL_WRITABLE |
+                                    MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  // It should have a message pipe.
+  MojoHandle handles[10];
+  uint32_t num_handlers = MOJO_ARRAYSIZE(handles);
+  CHECK_EQ(MojoReadMessage(mp.get().value(), nullptr,
+                           nullptr, &handles[0],
+                           &num_handlers, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  CHECK_EQ(num_handlers, 1u);
+
+  // Read data from the received message pipe.
+  CHECK_EQ(MojoWait(handles[0], MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                    MOJO_HANDLE_SIGNAL_WRITABLE |
+                                    MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  std::string read_buffer(100, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(handles[0], &read_buffer[0],
+                           &read_buffer_size, nullptr,
+                           0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  CHECK_EQ(read_buffer, std::string("hello"));
+
+  // Now write some data into the message pipe.
+  std::string write_buffer = "world";
+  CHECK_EQ(MojoWriteMessage(handles[0], write_buffer.data(),
+                            write_buffer.size(),
+                            nullptr, 0, MOJO_WRITE_MESSAGE_FLAG_NONE),
+            MOJO_RESULT_OK);
+  MojoClose(handles[0]);
+  return 0;
+}
+
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_MessagePipePassing DISABLED_MessagePipePassing
+#else
+#define MAYBE_MessagePipePassing MessagePipePassing
+#endif
+TEST_F(MultiprocessMessagePipeTest, MAYBE_MessagePipePassing) {
+  helper()->StartChild("CheckMessagePipe");
+
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(helper()->server_platform_handle.Pass());
+  MojoCreateSharedBufferOptions options;
+  options.struct_size = sizeof(options);
+  options.flags = MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE;
+
+  MojoHandle mp1, mp2;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoCreateMessagePipe(nullptr, &mp1, &mp2));
+
+  // Write a string into one end of the new message pipe and send the other end.
+  const std::string hello("hello");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp1, &hello[0], hello.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), nullptr, 0, &mp2, 1,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for a message from the child.
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWait(mp1, MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  EXPECT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+  EXPECT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+  std::string read_buffer(100, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(mp1, &read_buffer[0],
+                           &read_buffer_size, nullptr,
+                           0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  CHECK_EQ(read_buffer, std::string("world"));
+
+  MojoClose(mp1);
+  MojoClose(mp.release().value());
+
+  ASSERT_EQ(0, helper()->WaitForChildShutdown());
+}
+
+// Like above test, but verifies passing the other MP handle works as well.
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_MessagePipeTwoPassing DISABLED_MessagePipeTwoPassing
+#else
+#define MAYBE_MessagePipeTwoPassing MessagePipeTwoPassing
+#endif
+TEST_F(MultiprocessMessagePipeTest, MAYBE_MessagePipeTwoPassing) {
+  helper()->StartChild("CheckMessagePipe");
+
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(helper()->server_platform_handle.Pass());
+
+  MojoHandle mp1, mp2;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoCreateMessagePipe(nullptr, &mp2, &mp1));
+
+  // Write a string into one end of the new message pipe and send the other end.
+  const std::string hello("hello");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp1, &hello[0], hello.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), nullptr, 0, &mp2, 1,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for a message from the child.
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWait(mp1, MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  EXPECT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+  EXPECT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+  std::string read_buffer(100, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(mp1, &read_buffer[0],
+                           &read_buffer_size, nullptr,
+                           0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  CHECK_EQ(read_buffer, std::string("world"));
+
+  MojoClose(mp.release().value());
+
+  ASSERT_EQ(0, helper()->WaitForChildShutdown());
+}
+
+MOJO_MULTIPROCESS_TEST_CHILD_MAIN(DataPipeConsumer) {
+  SimplePlatformSupport platform_support;
+  base::MessageLoop message_loop;
+  base::TestIOThread test_io_thread(base::TestIOThread::kAutoStart);
+  test::ScopedIPCSupport ipc_support(test_io_thread.task_runner());
+
+  ScopedPlatformHandle client_platform_handle =
+      test::MultiprocessTestHelper::client_platform_handle.Pass();
+  CHECK(client_platform_handle.is_valid());
+
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(client_platform_handle.Pass());
+
+  // Wait for the first message from our parent.
+  HandleSignalsState hss;
+  CHECK_EQ(MojoWait(mp.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  // In this test, the parent definitely doesn't close its end of the message
+  // pipe before we do.
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                    MOJO_HANDLE_SIGNAL_WRITABLE |
+                                    MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  // It should have a message pipe.
+  MojoHandle handles[10];
+  uint32_t num_handlers = MOJO_ARRAYSIZE(handles);
+  CHECK_EQ(MojoReadMessage(mp.get().value(), nullptr,
+                           nullptr, &handles[0],
+                           &num_handlers, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  CHECK_EQ(num_handlers, 1u);
+
+  // Read data from the received message pipe.
+  CHECK_EQ(MojoWait(handles[0], MOJO_HANDLE_SIGNAL_READABLE,
+               MOJO_DEADLINE_INDEFINITE, &hss),
+           MOJO_RESULT_OK);
+  CHECK_EQ(hss.satisfied_signals,
+           MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE);
+  CHECK_EQ(hss.satisfiable_signals, MOJO_HANDLE_SIGNAL_READABLE |
+                                    MOJO_HANDLE_SIGNAL_WRITABLE |
+                                    MOJO_HANDLE_SIGNAL_PEER_CLOSED);
+
+  std::string read_buffer(100, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(handles[0], &read_buffer[0],
+                           &read_buffer_size, nullptr,
+                           0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  CHECK_EQ(read_buffer, std::string("hello"));
+
+  // Now write some data into the message pipe.
+  std::string write_buffer = "world";
+  CHECK_EQ(MojoWriteMessage(handles[0], write_buffer.data(),
+                            write_buffer.size(),
+                            nullptr, 0, MOJO_WRITE_MESSAGE_FLAG_NONE),
+            MOJO_RESULT_OK);
+  MojoClose(handles[0]);
+  return 0;
+}
+
+#if defined(OS_ANDROID)
+// Android multi-process tests are not executing the new process. This is flaky.
+#define MAYBE_DataPipeConsumer DISABLED_DataPipeConsumer
+#else
+#define MAYBE_DataPipeConsumer DataPipeConsumer
+#endif
+TEST_F(MultiprocessMessagePipeTest, MAYBE_DataPipeConsumer) {
+  helper()->StartChild("DataPipeConsumer");
+
+  ScopedMessagePipeHandle mp =
+      CreateMessagePipe(helper()->server_platform_handle.Pass());
+  MojoCreateSharedBufferOptions options;
+  options.struct_size = sizeof(options);
+  options.flags = MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE;
+
+  MojoHandle mp1, mp2;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoCreateMessagePipe(nullptr, &mp2, &mp1));
+
+  // Write a string into one end of the new message pipe and send the other end.
+  const std::string hello("hello");
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp1, &hello[0], hello.size(), nullptr, 0,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWriteMessage(mp.get().value(), nullptr, 0, &mp2, 1,
+                             MOJO_WRITE_MESSAGE_FLAG_NONE));
+
+  // Wait for a message from the child.
+  HandleSignalsState hss;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            MojoWait(mp1, MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  EXPECT_TRUE((hss.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE));
+  EXPECT_TRUE((hss.satisfiable_signals & MOJO_HANDLE_SIGNAL_READABLE));
+
+  std::string read_buffer(100, '\0');
+  uint32_t read_buffer_size = static_cast<uint32_t>(read_buffer.size());
+  CHECK_EQ(MojoReadMessage(mp1, &read_buffer[0],
+                           &read_buffer_size, nullptr,
+                           0, MOJO_READ_MESSAGE_FLAG_NONE),
+           MOJO_RESULT_OK);
+  read_buffer.resize(read_buffer_size);
+  CHECK_EQ(read_buffer, std::string("world"));
+
+  MojoClose(mp1);
+  MojoClose(mp.release().value());
+
+  ASSERT_EQ(0, helper()->WaitForChildShutdown());
+}
+
+}  // namespace
+}  // namespace edk
+}  // namespace mojo