chromium/third_party/googletest/src/googletest/src/gtest-death-test.cc

// Copyright 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

//
// This file implements death tests.

#include "gtest/gtest-death-test.h"

#include <stdlib.h>

#include <functional>
#include <memory>
#include <sstream>
#include <string>
#include <utility>
#include <vector>

#include "gtest/internal/custom/gtest.h"
#include "gtest/internal/gtest-port.h"

#ifdef GTEST_HAS_DEATH_TEST

#ifdef GTEST_OS_MAC
#include <crt_externs.h>
#endif  // GTEST_OS_MAC

#include <errno.h>
#include <fcntl.h>
#include <limits.h>

#ifdef GTEST_OS_LINUX
#include <signal.h>
#endif  // GTEST_OS_LINUX

#include <stdarg.h>

#ifdef GTEST_OS_WINDOWS
#include <windows.h>
#else
#include <sys/mman.h>
#include <sys/wait.h>
#endif  // GTEST_OS_WINDOWS

#ifdef GTEST_OS_QNX
#include <spawn.h>
#endif  // GTEST_OS_QNX

#ifdef GTEST_OS_FUCHSIA
#include <lib/fdio/fd.h>
#include <lib/fdio/io.h>
#include <lib/fdio/spawn.h>
#include <lib/zx/channel.h>
#include <lib/zx/port.h>
#include <lib/zx/process.h>
#include <lib/zx/socket.h>
#include <zircon/processargs.h>
#include <zircon/syscalls.h>
#include <zircon/syscalls/policy.h>
#include <zircon/syscalls/port.h>
#endif  // GTEST_OS_FUCHSIA

#endif  // GTEST_HAS_DEATH_TEST

#include "gtest/gtest-message.h"
#include "gtest/internal/gtest-string.h"
#include "src/gtest-internal-inl.h"

namespace testing {

// Constants.

// The default death test style.
//
// This is defined in internal/gtest-port.h as "fast", but can be overridden by
// a definition in internal/custom/gtest-port.h. The recommended value, which is
// used internally at Google, is "threadsafe".
static const char kDefaultDeathTestStyle[] =;

}  // namespace testing

GTEST_DEFINE_string_(
    death_test_style,
    testing::internal::StringFromGTestEnv("death_test_style",
                                          testing::kDefaultDeathTestStyle),
    "Indicates how to run a death test in a forked child process: "
    "\"threadsafe\" (child process re-executes the test binary "
    "from the beginning, running only the specific death test) or "
    "\"fast\" (child process runs the death test immediately "
    "after forking).");

GTEST_DEFINE_bool_(
    death_test_use_fork,
    testing::internal::BoolFromGTestEnv("death_test_use_fork", false),
    "Instructs to use fork()/_Exit() instead of clone() in death tests. "
    "Ignored and always uses fork() on POSIX systems where clone() is not "
    "implemented. Useful when running under valgrind or similar tools if "
    "those do not support clone(). Valgrind 3.3.1 will just fail if "
    "it sees an unsupported combination of clone() flags. "
    "It is not recommended to use this flag w/o valgrind though it will "
    "work in 99% of the cases. Once valgrind is fixed, this flag will "
    "most likely be removed.");

GTEST_DEFINE_string_(
    internal_run_death_test, "",
    "Indicates the file, line number, temporal index of "
    "the single death test to run, and a file descriptor to "
    "which a success code may be sent, all separated by "
    "the '|' characters.  This flag is specified if and only if the "
    "current process is a sub-process launched for running a thread-safe "
    "death test.  FOR INTERNAL USE ONLY.");

namespace testing {

#ifdef GTEST_HAS_DEATH_TEST

namespace internal {

// Valid only for fast death tests. Indicates the code is running in the
// child process of a fast style death test.
#if !defined(GTEST_OS_WINDOWS) && !defined(GTEST_OS_FUCHSIA)
static bool g_in_fast_death_test_child =;
#endif

// Returns a Boolean value indicating whether the caller is currently
// executing in the context of the death test child process.  Tools such as
// Valgrind heap checkers may need this to modify their behavior in death
// tests.  IMPORTANT: This is an internal utility.  Using it may break the
// implementation of death tests.  User code MUST NOT use it.
bool InDeathTestChild() {}

}  // namespace internal

// ExitedWithCode constructor.
ExitedWithCode::ExitedWithCode(int exit_code) :{}

// ExitedWithCode function-call operator.
bool ExitedWithCode::operator()(int exit_status) const {}

#if !defined(GTEST_OS_WINDOWS) && !defined(GTEST_OS_FUCHSIA)
// KilledBySignal constructor.
KilledBySignal::KilledBySignal(int signum) :{}

// KilledBySignal function-call operator.
bool KilledBySignal::operator()(int exit_status) const {}
#endif  // !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA

namespace internal {

// Utilities needed for death tests.

// Generates a textual description of a given exit code, in the format
// specified by wait(2).
static std::string ExitSummary(int exit_code) {}

// Returns true if exit_status describes a process that was terminated
// by a signal, or exited normally with a nonzero exit code.
bool ExitedUnsuccessfully(int exit_status) {}

#if !defined(GTEST_OS_WINDOWS) && !defined(GTEST_OS_FUCHSIA)
// Generates a textual failure message when a death test finds more than
// one thread running, or cannot determine the number of threads, prior
// to executing the given statement.  It is the responsibility of the
// caller not to pass a thread_count of 1.
static std::string DeathTestThreadWarning(size_t thread_count) {}
#endif  // !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA

// Flag characters for reporting a death test that did not die.
static const char kDeathTestLived =;
static const char kDeathTestReturned =;
static const char kDeathTestThrew =;
static const char kDeathTestInternalError =;

#ifdef GTEST_OS_FUCHSIA

// File descriptor used for the pipe in the child process.
static const int kFuchsiaReadPipeFd = 3;

#endif

// An enumeration describing all of the possible ways that a death test can
// conclude.  DIED means that the process died while executing the test
// code; LIVED means that process lived beyond the end of the test code;
// RETURNED means that the test statement attempted to execute a return
// statement, which is not allowed; THREW means that the test statement
// returned control by throwing an exception.  IN_PROGRESS means the test
// has not yet concluded.
enum DeathTestOutcome {};

// Routine for aborting the program which is safe to call from an
// exec-style death test child process, in which case the error
// message is propagated back to the parent process.  Otherwise, the
// message is simply printed to stderr.  In either case, the program
// then exits with status 1.
[[noreturn]] static void DeathTestAbort(const std::string& message) {}

// A replacement for CHECK that calls DeathTestAbort if the assertion
// fails.
#define GTEST_DEATH_TEST_CHECK_(expression)

// This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
// evaluating any system call that fulfills two conditions: it must return
// -1 on failure, and set errno to EINTR when it is interrupted and
// should be tried again.  The macro expands to a loop that repeatedly
// evaluates the expression as long as it evaluates to -1 and sets
// errno to EINTR.  If the expression evaluates to -1 but errno is
// something other than EINTR, DeathTestAbort is called.
#define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression)

// Returns the message describing the last system error in errno.
std::string GetLastErrnoDescription() {}

// This is called from a death test parent process to read a failure
// message from the death test child process and log it with the FATAL
// severity. On Windows, the message is read from a pipe handle. On other
// platforms, it is read from a file descriptor.
static void FailFromInternalError(int fd) {}

// Death test constructor.  Increments the running death test count
// for the current test.
DeathTest::DeathTest() {}

// Creates and returns a death test by dispatching to the current
// death test factory.
bool DeathTest::Create(const char* statement,
                       Matcher<const std::string&> matcher, const char* file,
                       int line, DeathTest** test) {}

const char* DeathTest::LastMessage() {}

void DeathTest::set_last_death_test_message(const std::string& message) {}

std::string DeathTest::last_death_test_message_;

// Provides cross platform implementation for some death functionality.
class DeathTestImpl : public DeathTest {};

// Called in the parent process only. Reads the result code of the death
// test child process via a pipe, interprets it to set the outcome_
// member, and closes read_fd_.  Outputs diagnostics and terminates in
// case of unexpected codes.
void DeathTestImpl::ReadAndInterpretStatusByte() {}

std::string DeathTestImpl::GetErrorLogs() {}

// Signals that the death test code which should have exited, didn't.
// Should be called only in a death test child process.
// Writes a status byte to the child's status file descriptor, then
// calls _Exit(1).
void DeathTestImpl::Abort(AbortReason reason) {}

// Returns an indented copy of stderr output for a death test.
// This makes distinguishing death test output lines from regular log lines
// much easier.
static ::std::string FormatDeathTestOutput(const ::std::string& output) {}

// Assesses the success or failure of a death test, using both private
// members which have previously been set, and one argument:
//
// Private data members:
//   outcome:  An enumeration describing how the death test
//             concluded: DIED, LIVED, THREW, or RETURNED.  The death test
//             fails in the latter three cases.
//   status:   The exit status of the child process. On *nix, it is in the
//             in the format specified by wait(2). On Windows, this is the
//             value supplied to the ExitProcess() API or a numeric code
//             of the exception that terminated the program.
//   matcher_: A matcher that's expected to match the stderr output by the child
//             process.
//
// Argument:
//   status_ok: true if exit_status is acceptable in the context of
//              this particular death test, which fails if it is false
//
// Returns true if and only if all of the above conditions are met.  Otherwise,
// the first failing condition, in the order given above, is the one that is
// reported. Also sets the last death test message string.
bool DeathTestImpl::Passed(bool status_ok) {}

#ifndef GTEST_OS_WINDOWS
// Note: The return value points into args, so the return value's lifetime is
// bound to that of args.
static std::vector<char*> CreateArgvFromArgs(std::vector<std::string>& args) {}
#endif

#ifdef GTEST_OS_WINDOWS
// WindowsDeathTest implements death tests on Windows. Due to the
// specifics of starting new processes on Windows, death tests there are
// always threadsafe, and Google Test considers the
// --gtest_death_test_style=fast setting to be equivalent to
// --gtest_death_test_style=threadsafe there.
//
// A few implementation notes:  Like the Linux version, the Windows
// implementation uses pipes for child-to-parent communication. But due to
// the specifics of pipes on Windows, some extra steps are required:
//
// 1. The parent creates a communication pipe and stores handles to both
//    ends of it.
// 2. The parent starts the child and provides it with the information
//    necessary to acquire the handle to the write end of the pipe.
// 3. The child acquires the write end of the pipe and signals the parent
//    using a Windows event.
// 4. Now the parent can release the write end of the pipe on its side. If
//    this is done before step 3, the object's reference count goes down to
//    0 and it is destroyed, preventing the child from acquiring it. The
//    parent now has to release it, or read operations on the read end of
//    the pipe will not return when the child terminates.
// 5. The parent reads child's output through the pipe (outcome code and
//    any possible error messages) from the pipe, and its stderr and then
//    determines whether to fail the test.
//
// Note: to distinguish Win32 API calls from the local method and function
// calls, the former are explicitly resolved in the global namespace.
//
class WindowsDeathTest : public DeathTestImpl {
 public:
  WindowsDeathTest(const char* a_statement, Matcher<const std::string&> matcher,
                   const char* file, int line)
      : DeathTestImpl(a_statement, std::move(matcher)),
        file_(file),
        line_(line) {}

  // All of these virtual functions are inherited from DeathTest.
  virtual int Wait();
  virtual TestRole AssumeRole();

 private:
  // The name of the file in which the death test is located.
  const char* const file_;
  // The line number on which the death test is located.
  const int line_;
  // Handle to the write end of the pipe to the child process.
  AutoHandle write_handle_;
  // Child process handle.
  AutoHandle child_handle_;
  // Event the child process uses to signal the parent that it has
  // acquired the handle to the write end of the pipe. After seeing this
  // event the parent can release its own handles to make sure its
  // ReadFile() calls return when the child terminates.
  AutoHandle event_handle_;
};

// Waits for the child in a death test to exit, returning its exit
// status, or 0 if no child process exists.  As a side effect, sets the
// outcome data member.
int WindowsDeathTest::Wait() {
  if (!spawned()) return 0;

  // Wait until the child either signals that it has acquired the write end
  // of the pipe or it dies.
  const HANDLE wait_handles[2] = {child_handle_.Get(), event_handle_.Get()};
  switch (::WaitForMultipleObjects(2, wait_handles,
                                   FALSE,  // Waits for any of the handles.
                                   INFINITE)) {
    case WAIT_OBJECT_0:
    case WAIT_OBJECT_0 + 1:
      break;
    default:
      GTEST_DEATH_TEST_CHECK_(false);  // Should not get here.
  }

  // The child has acquired the write end of the pipe or exited.
  // We release the handle on our side and continue.
  write_handle_.Reset();
  event_handle_.Reset();

  ReadAndInterpretStatusByte();

  // Waits for the child process to exit if it haven't already. This
  // returns immediately if the child has already exited, regardless of
  // whether previous calls to WaitForMultipleObjects synchronized on this
  // handle or not.
  GTEST_DEATH_TEST_CHECK_(WAIT_OBJECT_0 ==
                          ::WaitForSingleObject(child_handle_.Get(), INFINITE));
  DWORD status_code;
  GTEST_DEATH_TEST_CHECK_(
      ::GetExitCodeProcess(child_handle_.Get(), &status_code) != FALSE);
  child_handle_.Reset();
  set_status(static_cast<int>(status_code));
  return status();
}

// The AssumeRole process for a Windows death test.  It creates a child
// process with the same executable as the current process to run the
// death test.  The child process is given the --gtest_filter and
// --gtest_internal_run_death_test flags such that it knows to run the
// current death test only.
DeathTest::TestRole WindowsDeathTest::AssumeRole() {
  const UnitTestImpl* const impl = GetUnitTestImpl();
  const InternalRunDeathTestFlag* const flag =
      impl->internal_run_death_test_flag();
  const TestInfo* const info = impl->current_test_info();
  const int death_test_index = info->result()->death_test_count();

  if (flag != nullptr) {
    // ParseInternalRunDeathTestFlag() has performed all the necessary
    // processing.
    set_write_fd(flag->write_fd());
    return EXECUTE_TEST;
  }

  // WindowsDeathTest uses an anonymous pipe to communicate results of
  // a death test.
  SECURITY_ATTRIBUTES handles_are_inheritable = {sizeof(SECURITY_ATTRIBUTES),
                                                 nullptr, TRUE};
  HANDLE read_handle, write_handle;
  GTEST_DEATH_TEST_CHECK_(::CreatePipe(&read_handle, &write_handle,
                                       &handles_are_inheritable,
                                       0)  // Default buffer size.
                          != FALSE);
  set_read_fd(
      ::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle), O_RDONLY));
  write_handle_.Reset(write_handle);
  event_handle_.Reset(::CreateEvent(
      &handles_are_inheritable,
      TRUE,       // The event will automatically reset to non-signaled state.
      FALSE,      // The initial state is non-signalled.
      nullptr));  // The even is unnamed.
  GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != nullptr);
  const std::string filter_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
                                  "filter=" + info->test_suite_name() + "." +
                                  info->name();
  const std::string internal_flag =
      std::string("--") + GTEST_FLAG_PREFIX_ +
      "internal_run_death_test=" + file_ + "|" + StreamableToString(line_) +
      "|" + StreamableToString(death_test_index) + "|" +
      StreamableToString(static_cast<unsigned int>(::GetCurrentProcessId())) +
      // size_t has the same width as pointers on both 32-bit and 64-bit
      // Windows platforms.
      // See https://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
      "|" + StreamableToString(reinterpret_cast<size_t>(write_handle)) + "|" +
      StreamableToString(reinterpret_cast<size_t>(event_handle_.Get()));

  char executable_path[_MAX_PATH + 1];  // NOLINT
  GTEST_DEATH_TEST_CHECK_(_MAX_PATH + 1 != ::GetModuleFileNameA(nullptr,
                                                                executable_path,
                                                                _MAX_PATH));

  std::string command_line = std::string(::GetCommandLineA()) + " " +
                             filter_flag + " \"" + internal_flag + "\"";

  DeathTest::set_last_death_test_message("");

  CaptureStderr();
  // Flush the log buffers since the log streams are shared with the child.
  FlushInfoLog();

  // The child process will share the standard handles with the parent.
  STARTUPINFOA startup_info;
  memset(&startup_info, 0, sizeof(STARTUPINFO));
  startup_info.dwFlags = STARTF_USESTDHANDLES;
  startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
  startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
  startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);

  PROCESS_INFORMATION process_info;
  GTEST_DEATH_TEST_CHECK_(
      ::CreateProcessA(
          executable_path, const_cast<char*>(command_line.c_str()),
          nullptr,  // Returned process handle is not inheritable.
          nullptr,  // Returned thread handle is not inheritable.
          TRUE,  // Child inherits all inheritable handles (for write_handle_).
          0x0,   // Default creation flags.
          nullptr,  // Inherit the parent's environment.
          UnitTest::GetInstance()->original_working_dir(), &startup_info,
          &process_info) != FALSE);
  child_handle_.Reset(process_info.hProcess);
  ::CloseHandle(process_info.hThread);
  set_spawned(true);
  return OVERSEE_TEST;
}

#elif defined(GTEST_OS_FUCHSIA)

class FuchsiaDeathTest : public DeathTestImpl {
 public:
  FuchsiaDeathTest(const char* a_statement, Matcher<const std::string&> matcher,
                   const char* file, int line)
      : DeathTestImpl(a_statement, std::move(matcher)),
        file_(file),
        line_(line) {}

  // All of these virtual functions are inherited from DeathTest.
  int Wait() override;
  TestRole AssumeRole() override;
  std::string GetErrorLogs() override;

 private:
  // The name of the file in which the death test is located.
  const char* const file_;
  // The line number on which the death test is located.
  const int line_;
  // The stderr data captured by the child process.
  std::string captured_stderr_;

  zx::process child_process_;
  zx::channel exception_channel_;
  zx::socket stderr_socket_;
};

// Waits for the child in a death test to exit, returning its exit
// status, or 0 if no child process exists.  As a side effect, sets the
// outcome data member.
int FuchsiaDeathTest::Wait() {
  const int kProcessKey = 0;
  const int kSocketKey = 1;
  const int kExceptionKey = 2;

  if (!spawned()) return 0;

  // Create a port to wait for socket/task/exception events.
  zx_status_t status_zx;
  zx::port port;
  status_zx = zx::port::create(0, &port);
  GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

  // Register to wait for the child process to terminate.
  status_zx =
      child_process_.wait_async(port, kProcessKey, ZX_PROCESS_TERMINATED, 0);
  GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

  // Register to wait for the socket to be readable or closed.
  status_zx = stderr_socket_.wait_async(
      port, kSocketKey, ZX_SOCKET_READABLE | ZX_SOCKET_PEER_CLOSED, 0);
  GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

  // Register to wait for an exception.
  status_zx = exception_channel_.wait_async(port, kExceptionKey,
                                            ZX_CHANNEL_READABLE, 0);
  GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

  bool process_terminated = false;
  bool socket_closed = false;
  do {
    zx_port_packet_t packet = {};
    status_zx = port.wait(zx::time::infinite(), &packet);
    GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

    if (packet.key == kExceptionKey) {
      // Process encountered an exception. Kill it directly rather than
      // letting other handlers process the event. We will get a kProcessKey
      // event when the process actually terminates.
      status_zx = child_process_.kill();
      GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
    } else if (packet.key == kProcessKey) {
      // Process terminated.
      GTEST_DEATH_TEST_CHECK_(ZX_PKT_IS_SIGNAL_ONE(packet.type));
      GTEST_DEATH_TEST_CHECK_(packet.signal.observed & ZX_PROCESS_TERMINATED);
      process_terminated = true;
    } else if (packet.key == kSocketKey) {
      GTEST_DEATH_TEST_CHECK_(ZX_PKT_IS_SIGNAL_ONE(packet.type));
      if (packet.signal.observed & ZX_SOCKET_READABLE) {
        // Read data from the socket.
        constexpr size_t kBufferSize = 1024;
        do {
          size_t old_length = captured_stderr_.length();
          size_t bytes_read = 0;
          captured_stderr_.resize(old_length + kBufferSize);
          status_zx =
              stderr_socket_.read(0, &captured_stderr_.front() + old_length,
                                  kBufferSize, &bytes_read);
          captured_stderr_.resize(old_length + bytes_read);
        } while (status_zx == ZX_OK);
        if (status_zx == ZX_ERR_PEER_CLOSED) {
          socket_closed = true;
        } else {
          GTEST_DEATH_TEST_CHECK_(status_zx == ZX_ERR_SHOULD_WAIT);
          status_zx = stderr_socket_.wait_async(
              port, kSocketKey, ZX_SOCKET_READABLE | ZX_SOCKET_PEER_CLOSED, 0);
          GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
        }
      } else {
        GTEST_DEATH_TEST_CHECK_(packet.signal.observed & ZX_SOCKET_PEER_CLOSED);
        socket_closed = true;
      }
    }
  } while (!process_terminated && !socket_closed);

  ReadAndInterpretStatusByte();

  zx_info_process_t buffer;
  status_zx = child_process_.get_info(ZX_INFO_PROCESS, &buffer, sizeof(buffer),
                                      nullptr, nullptr);
  GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);

  GTEST_DEATH_TEST_CHECK_(buffer.flags & ZX_INFO_PROCESS_FLAG_EXITED);
  set_status(static_cast<int>(buffer.return_code));
  return status();
}

// The AssumeRole process for a Fuchsia death test.  It creates a child
// process with the same executable as the current process to run the
// death test.  The child process is given the --gtest_filter and
// --gtest_internal_run_death_test flags such that it knows to run the
// current death test only.
DeathTest::TestRole FuchsiaDeathTest::AssumeRole() {
  const UnitTestImpl* const impl = GetUnitTestImpl();
  const InternalRunDeathTestFlag* const flag =
      impl->internal_run_death_test_flag();
  const TestInfo* const info = impl->current_test_info();
  const int death_test_index = info->result()->death_test_count();

  if (flag != nullptr) {
    // ParseInternalRunDeathTestFlag() has performed all the necessary
    // processing.
    set_write_fd(kFuchsiaReadPipeFd);
    return EXECUTE_TEST;
  }

  // Flush the log buffers since the log streams are shared with the child.
  FlushInfoLog();

  // Build the child process command line.
  const std::string filter_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
                                  "filter=" + info->test_suite_name() + "." +
                                  info->name();
  const std::string internal_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
                                    kInternalRunDeathTestFlag + "=" + file_ +
                                    "|" + StreamableToString(line_) + "|" +
                                    StreamableToString(death_test_index);

  std::vector<std::string> args = GetInjectableArgvs();
  args.push_back(filter_flag);
  args.push_back(internal_flag);

  // Build the pipe for communication with the child.
  zx_status_t status;
  zx_handle_t child_pipe_handle;
  int child_pipe_fd;
  status = fdio_pipe_half(&child_pipe_fd, &child_pipe_handle);
  GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
  set_read_fd(child_pipe_fd);

  // Set the pipe handle for the child.
  fdio_spawn_action_t spawn_actions[2] = {};
  fdio_spawn_action_t* add_handle_action = &spawn_actions[0];
  add_handle_action->action = FDIO_SPAWN_ACTION_ADD_HANDLE;
  add_handle_action->h.id = PA_HND(PA_FD, kFuchsiaReadPipeFd);
  add_handle_action->h.handle = child_pipe_handle;

  // Create a socket pair will be used to receive the child process' stderr.
  zx::socket stderr_producer_socket;
  status = zx::socket::create(0, &stderr_producer_socket, &stderr_socket_);
  GTEST_DEATH_TEST_CHECK_(status >= 0);
  int stderr_producer_fd = -1;
  status =
      fdio_fd_create(stderr_producer_socket.release(), &stderr_producer_fd);
  GTEST_DEATH_TEST_CHECK_(status >= 0);

  // Make the stderr socket nonblocking.
  GTEST_DEATH_TEST_CHECK_(fcntl(stderr_producer_fd, F_SETFL, 0) == 0);

  fdio_spawn_action_t* add_stderr_action = &spawn_actions[1];
  add_stderr_action->action = FDIO_SPAWN_ACTION_CLONE_FD;
  add_stderr_action->fd.local_fd = stderr_producer_fd;
  add_stderr_action->fd.target_fd = STDERR_FILENO;

  // Create a child job.
  zx_handle_t child_job = ZX_HANDLE_INVALID;
  status = zx_job_create(zx_job_default(), 0, &child_job);
  GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
  zx_policy_basic_t policy;
  policy.condition = ZX_POL_NEW_ANY;
  policy.policy = ZX_POL_ACTION_ALLOW;
  status = zx_job_set_policy(child_job, ZX_JOB_POL_RELATIVE, ZX_JOB_POL_BASIC,
                             &policy, 1);
  GTEST_DEATH_TEST_CHECK_(status == ZX_OK);

  // Create an exception channel attached to the |child_job|, to allow
  // us to suppress the system default exception handler from firing.
  status = zx_task_create_exception_channel(
      child_job, 0, exception_channel_.reset_and_get_address());
  GTEST_DEATH_TEST_CHECK_(status == ZX_OK);

  // Spawn the child process.
  // Note: The test component must have `fuchsia.process.Launcher` declared
  // in its manifest. (Fuchsia integration tests require creating a
  // "Fuchsia Test Component" which contains a "Fuchsia Component Manifest")
  // Launching processes is a privileged operation in Fuchsia, and the
  // declaration indicates that the ability is required for the component.
  std::vector<char*> argv = CreateArgvFromArgs(args);
  status = fdio_spawn_etc(child_job, FDIO_SPAWN_CLONE_ALL, argv[0], argv.data(),
                          nullptr, 2, spawn_actions,
                          child_process_.reset_and_get_address(), nullptr);
  GTEST_DEATH_TEST_CHECK_(status == ZX_OK);

  set_spawned(true);
  return OVERSEE_TEST;
}

std::string FuchsiaDeathTest::GetErrorLogs() { return captured_stderr_; }

#else  // We are neither on Windows, nor on Fuchsia.

// ForkingDeathTest provides implementations for most of the abstract
// methods of the DeathTest interface.  Only the AssumeRole method is
// left undefined.
class ForkingDeathTest : public DeathTestImpl {};

// Constructs a ForkingDeathTest.
ForkingDeathTest::ForkingDeathTest(const char* a_statement,
                                   Matcher<const std::string&> matcher)
    :{}

// Waits for the child in a death test to exit, returning its exit
// status, or 0 if no child process exists.  As a side effect, sets the
// outcome data member.
int ForkingDeathTest::Wait() {}

// A concrete death test class that forks, then immediately runs the test
// in the child process.
class NoExecDeathTest : public ForkingDeathTest {};

// The AssumeRole process for a fork-and-run death test.  It implements a
// straightforward fork, with a simple pipe to transmit the status byte.
DeathTest::TestRole NoExecDeathTest::AssumeRole() {}

// A concrete death test class that forks and re-executes the main
// program from the beginning, with command-line flags set that cause
// only this specific death test to be run.
class ExecDeathTest : public ForkingDeathTest {};

// A struct that encompasses the arguments to the child process of a
// threadsafe-style death test process.
struct ExecDeathTestArgs {};

#ifdef GTEST_OS_QNX
extern "C" char** environ;
#else   // GTEST_OS_QNX
// The main function for a threadsafe-style death test child process.
// This function is called in a clone()-ed process and thus must avoid
// any potentially unsafe operations like malloc or libc functions.
static int ExecDeathTestChildMain(void* child_arg) {}
#endif  // GTEST_OS_QNX

#if GTEST_HAS_CLONE
// Two utility routines that together determine the direction the stack
// grows.
// This could be accomplished more elegantly by a single recursive
// function, but we want to guard against the unlikely possibility of
// a smart compiler optimizing the recursion away.
//
// GTEST_NO_INLINE_ is required to prevent GCC 4.6 from inlining
// StackLowerThanAddress into StackGrowsDown, which then doesn't give
// correct answer.
static void StackLowerThanAddress(const void* ptr,
                                  bool* result) GTEST_NO_INLINE_;
// Make sure sanitizers do not tamper with the stack here.
// Ideally, we want to use `__builtin_frame_address` instead of a local variable
// address with sanitizer disabled, but it does not work when the
// compiler optimizes the stack frame out, which happens on PowerPC targets.
// HWAddressSanitizer add a random tag to the MSB of the local variable address,
// making comparison result unpredictable.
GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
GTEST_ATTRIBUTE_NO_SANITIZE_HWADDRESS_
static void StackLowerThanAddress(const void* ptr, bool* result) {}

// Make sure AddressSanitizer does not tamper with the stack here.
GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
GTEST_ATTRIBUTE_NO_SANITIZE_HWADDRESS_
static bool StackGrowsDown() {}
#endif  // GTEST_HAS_CLONE

// Spawns a child process with the same executable as the current process in
// a thread-safe manner and instructs it to run the death test.  The
// implementation uses fork(2) + exec.  On systems where clone(2) is
// available, it is used instead, being slightly more thread-safe.  On QNX,
// fork supports only single-threaded environments, so this function uses
// spawn(2) there instead.  The function dies with an error message if
// anything goes wrong.
static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {}

// The AssumeRole process for a fork-and-exec death test.  It re-executes the
// main program from the beginning, setting the --gtest_filter
// and --gtest_internal_run_death_test flags to cause only the current
// death test to be re-run.
DeathTest::TestRole ExecDeathTest::AssumeRole() {}

#endif  // !GTEST_OS_WINDOWS

// Creates a concrete DeathTest-derived class that depends on the
// --gtest_death_test_style flag, and sets the pointer pointed to
// by the "test" argument to its address.  If the test should be
// skipped, sets that pointer to NULL.  Returns true, unless the
// flag is set to an invalid value.
bool DefaultDeathTestFactory::Create(const char* statement,
                                     Matcher<const std::string&> matcher,
                                     const char* file, int line,
                                     DeathTest** test) {}

#ifdef GTEST_OS_WINDOWS
// Recreates the pipe and event handles from the provided parameters,
// signals the event, and returns a file descriptor wrapped around the pipe
// handle. This function is called in the child process only.
static int GetStatusFileDescriptor(unsigned int parent_process_id,
                                   size_t write_handle_as_size_t,
                                   size_t event_handle_as_size_t) {
  AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
                                                 FALSE,  // Non-inheritable.
                                                 parent_process_id));
  if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
    DeathTestAbort("Unable to open parent process " +
                   StreamableToString(parent_process_id));
  }

  GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));

  const HANDLE write_handle = reinterpret_cast<HANDLE>(write_handle_as_size_t);
  HANDLE dup_write_handle;

  // The newly initialized handle is accessible only in the parent
  // process. To obtain one accessible within the child, we need to use
  // DuplicateHandle.
  if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
                         ::GetCurrentProcess(), &dup_write_handle,
                         0x0,    // Requested privileges ignored since
                                 // DUPLICATE_SAME_ACCESS is used.
                         FALSE,  // Request non-inheritable handler.
                         DUPLICATE_SAME_ACCESS)) {
    DeathTestAbort("Unable to duplicate the pipe handle " +
                   StreamableToString(write_handle_as_size_t) +
                   " from the parent process " +
                   StreamableToString(parent_process_id));
  }

  const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
  HANDLE dup_event_handle;

  if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
                         ::GetCurrentProcess(), &dup_event_handle, 0x0, FALSE,
                         DUPLICATE_SAME_ACCESS)) {
    DeathTestAbort("Unable to duplicate the event handle " +
                   StreamableToString(event_handle_as_size_t) +
                   " from the parent process " +
                   StreamableToString(parent_process_id));
  }

  const int write_fd =
      ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
  if (write_fd == -1) {
    DeathTestAbort("Unable to convert pipe handle " +
                   StreamableToString(write_handle_as_size_t) +
                   " to a file descriptor");
  }

  // Signals the parent that the write end of the pipe has been acquired
  // so the parent can release its own write end.
  ::SetEvent(dup_event_handle);

  return write_fd;
}
#endif  // GTEST_OS_WINDOWS

// Returns a newly created InternalRunDeathTestFlag object with fields
// initialized from the GTEST_FLAG(internal_run_death_test) flag if
// the flag is specified; otherwise returns NULL.
InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {}

}  // namespace internal

#endif  // GTEST_HAS_DEATH_TEST

}  // namespace testing