Subversion Repositories Kolibri OS

// 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.

//

// Author: wan@google.com (Zhanyong Wan), vladl@google.com (Vlad Losev)

//

// This file implements death tests.

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

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

#if GTEST_HAS_DEATH_TEST

# if GTEST_OS_MAC

#  include 

# endif  // GTEST_OS_MAC

# include 

# include 

# include 

# include 

# if GTEST_OS_WINDOWS

#  include 

# else

#  include 

#  include 

# endif  // GTEST_OS_WINDOWS

#endif  // GTEST_HAS_DEATH_TEST

#include "gtest/gtest-message.h"

#include "gtest/internal/gtest-string.h"

// Indicates that this translation unit is part of Google Test's

// implementation.  It must come before gtest-internal-inl.h is

// included, or there will be a compiler error.  This trick is to

// prevent a user from accidentally including gtest-internal-inl.h in

// his code.

#define GTEST_IMPLEMENTATION_ 1

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

#undef GTEST_IMPLEMENTATION_

namespace testing {

// Constants.

// The default death test style.

static const char kDefaultDeathTestStyle[] = "fast";

GTEST_DEFINE_string_(

    death_test_style,

    internal::StringFromGTestEnv("death_test_style", 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,

    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.");

namespace internal {

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 "

    "colons.  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 internal

#if GTEST_HAS_DEATH_TEST

// ExitedWithCode constructor.

ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {

}

// ExitedWithCode function-call operator.

bool ExitedWithCode::operator()(int exit_status) const {

# if GTEST_OS_WINDOWS

  return exit_status == exit_code_;

# else

  return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;

# endif  // GTEST_OS_WINDOWS

}

# if !GTEST_OS_WINDOWS

// KilledBySignal constructor.

KilledBySignal::KilledBySignal(int signum) : signum_(signum) {

}

// KilledBySignal function-call operator.

bool KilledBySignal::operator()(int exit_status) const {

  return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;

}

# endif  // !GTEST_OS_WINDOWS

namespace internal {

// Utilities needed for death tests.

// Generates a textual description of a given exit code, in the format

// specified by wait(2).

static String ExitSummary(int exit_code) {

  Message m;

# if GTEST_OS_WINDOWS

  m << "Exited with exit status " << exit_code;

# else

  if (WIFEXITED(exit_code)) {

    m << "Exited with exit status " << WEXITSTATUS(exit_code);

  } else if (WIFSIGNALED(exit_code)) {

    m << "Terminated by signal " << WTERMSIG(exit_code);

  }

#  ifdef WCOREDUMP

  if (WCOREDUMP(exit_code)) {

    m << " (core dumped)";

  }

#  endif

# endif  // GTEST_OS_WINDOWS

  return m.GetString();

}

// 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) {

  return !ExitedWithCode(0)(exit_status);

}

# if !GTEST_OS_WINDOWS

// 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 String DeathTestThreadWarning(size_t thread_count) {

  Message msg;

  msg << "Death tests use fork(), which is unsafe particularly"

      << " in a threaded context. For this test, " << GTEST_NAME_ << " ";

  if (thread_count == 0)

    msg << "couldn't detect the number of threads.";

  else

    msg << "detected " << thread_count << " threads.";

  return msg.GetString();

}

# endif  // !GTEST_OS_WINDOWS

// Flag characters for reporting a death test that did not die.

static const char kDeathTestLived = 'L';

static const char kDeathTestReturned = 'R';

static const char kDeathTestThrew = 'T';

static const char kDeathTestInternalError = 'I';

// 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.

// TODO(vladl@google.com): Unify names and possibly values for

// AbortReason, DeathTestOutcome, and flag characters above.

enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED, THREW };

// 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.

void DeathTestAbort(const String& message) {

  // On a POSIX system, this function may be called from a threadsafe-style

  // death test child process, which operates on a very small stack.  Use

  // the heap for any additional non-minuscule memory requirements.

  const InternalRunDeathTestFlag* const flag =

      GetUnitTestImpl()->internal_run_death_test_flag();

  if (flag != NULL) {

    FILE* parent = posix::FDOpen(flag->write_fd(), "w");

    fputc(kDeathTestInternalError, parent);

    fprintf(parent, "%s", message.c_str());

    fflush(parent);

    _exit(1);

  } else {

    fprintf(stderr, "%s", message.c_str());

    fflush(stderr);

    posix::Abort();

  }

}

// A replacement for CHECK that calls DeathTestAbort if the assertion

// fails.

# define GTEST_DEATH_TEST_CHECK_(expression) \

  do { \

    if (!::testing::internal::IsTrue(expression)) { \

      DeathTestAbort(::testing::internal::String::Format( \

          "CHECK failed: File %s, line %d: %s", \

          __FILE__, __LINE__, #expression)); \

    } \

  } while (::testing::internal::AlwaysFalse())

// 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) \

  do { \

    int gtest_retval; \

    do { \

      gtest_retval = (expression); \

    } while (gtest_retval == -1 && errno == EINTR); \

    if (gtest_retval == -1) { \

      DeathTestAbort(::testing::internal::String::Format( \

          "CHECK failed: File %s, line %d: %s != -1", \

          __FILE__, __LINE__, #expression)); \

    } \

  } while (::testing::internal::AlwaysFalse())

// Returns the message describing the last system error in errno.

String GetLastErrnoDescription() {

    return String(errno == 0 ? "" : posix::StrError(errno));

}

// 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) {

  Message error;

  char buffer[256];

  int num_read;

  do {

    while ((num_read = posix::Read(fd, buffer, 255)) > 0) {

      buffer[num_read] = '\0';

      error << buffer;

    }

  } while (num_read == -1 && errno == EINTR);

  if (num_read == 0) {

    GTEST_LOG_(FATAL) << error.GetString();

  } else {

    const int last_error = errno;

    GTEST_LOG_(FATAL) << "Error while reading death test internal: "

                      << GetLastErrnoDescription() << " [" << last_error << "]";

  }

}

// Death test constructor.  Increments the running death test count

// for the current test.

DeathTest::DeathTest() {

  TestInfo* const info = GetUnitTestImpl()->current_test_info();

  if (info == NULL) {

    DeathTestAbort("Cannot run a death test outside of a TEST or "

                   "TEST_F construct");

  }

}

// Creates and returns a death test by dispatching to the current

// death test factory.

bool DeathTest::Create(const char* statement, const RE* regex,

                       const char* file, int line, DeathTest** test) {

  return GetUnitTestImpl()->death_test_factory()->Create(

      statement, regex, file, line, test);

}

const char* DeathTest::LastMessage() {

  return last_death_test_message_.c_str();

}

void DeathTest::set_last_death_test_message(const String& message) {

  last_death_test_message_ = message;

}

String DeathTest::last_death_test_message_;

// Provides cross platform implementation for some death functionality.

class DeathTestImpl : public DeathTest {

 protected:

  DeathTestImpl(const char* a_statement, const RE* a_regex)

      : statement_(a_statement),

        regex_(a_regex),

        spawned_(false),

        status_(-1),

        outcome_(IN_PROGRESS),

        read_fd_(-1),

        write_fd_(-1) {}

  // read_fd_ is expected to be closed and cleared by a derived class.

  ~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }

  void Abort(AbortReason reason);

  virtual bool Passed(bool status_ok);

  const char* statement() const { return statement_; }

  const RE* regex() const { return regex_; }

  bool spawned() const { return spawned_; }

  void set_spawned(bool is_spawned) { spawned_ = is_spawned; }

  int status() const { return status_; }

  void set_status(int a_status) { status_ = a_status; }

  DeathTestOutcome outcome() const { return outcome_; }

  void set_outcome(DeathTestOutcome an_outcome) { outcome_ = an_outcome; }

  int read_fd() const { return read_fd_; }

  void set_read_fd(int fd) { read_fd_ = fd; }

  int write_fd() const { return write_fd_; }

  void set_write_fd(int fd) { write_fd_ = fd; }

  // 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 ReadAndInterpretStatusByte();

 private:

  // The textual content of the code this object is testing.  This class

  // doesn't own this string and should not attempt to delete it.

  const char* const statement_;

  // The regular expression which test output must match.  DeathTestImpl

  // doesn't own this object and should not attempt to delete it.

  const RE* const regex_;

  // True if the death test child process has been successfully spawned.

  bool spawned_;

  // The exit status of the child process.

  int status_;

  // How the death test concluded.

  DeathTestOutcome outcome_;

  // Descriptor to the read end of the pipe to the child process.  It is

  // always -1 in the child process.  The child keeps its write end of the

  // pipe in write_fd_.

  int read_fd_;

  // Descriptor to the child's write end of the pipe to the parent process.

  // It is always -1 in the parent process.  The parent keeps its end of the

  // pipe in read_fd_.

  int write_fd_;

};

// 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() {

  char flag;

  int bytes_read;

  // The read() here blocks until data is available (signifying the

  // failure of the death test) or until the pipe is closed (signifying

  // its success), so it's okay to call this in the parent before

  // the child process has exited.

  do {

    bytes_read = posix::Read(read_fd(), &flag, 1);

  } while (bytes_read == -1 && errno == EINTR);

  if (bytes_read == 0) {

    set_outcome(DIED);

  } else if (bytes_read == 1) {

    switch (flag) {

      case kDeathTestReturned:

        set_outcome(RETURNED);

        break;

      case kDeathTestThrew:

        set_outcome(THREW);

        break;

      case kDeathTestLived:

        set_outcome(LIVED);

        break;

      case kDeathTestInternalError:

        FailFromInternalError(read_fd());  // Does not return.

        break;

      default:

        GTEST_LOG_(FATAL) << "Death test child process reported "

                          << "unexpected status byte ("

                          << static_cast(flag) << ")";

    }

  } else {

    GTEST_LOG_(FATAL) << "Read from death test child process failed: "

                      << GetLastErrnoDescription();

  }

  GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));

  set_read_fd(-1);

}

// 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) {

  // The parent process considers the death test to be a failure if

  // it finds any data in our pipe.  So, here we write a single flag byte

  // to the pipe, then exit.

  const char status_ch =

      reason == TEST_DID_NOT_DIE ? kDeathTestLived :

      reason == TEST_THREW_EXCEPTION ? kDeathTestThrew : kDeathTestReturned;

  GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));

  // We are leaking the descriptor here because on some platforms (i.e.,

  // when built as Windows DLL), destructors of global objects will still

  // run after calling _exit(). On such systems, write_fd_ will be

  // indirectly closed from the destructor of UnitTestImpl, causing double

  // close if it is also closed here. On debug configurations, double close

  // may assert. As there are no in-process buffers to flush here, we are

  // relying on the OS to close the descriptor after the process terminates

  // when the destructors are not run.

  _exit(1);  // Exits w/o any normal exit hooks (we were supposed to crash)

}

// 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) {

  ::std::string ret;

  for (size_t at = 0; ; ) {

    const size_t line_end = output.find('\n', at);

    ret += "[  DEATH   ] ";

    if (line_end == ::std::string::npos) {

      ret += output.substr(at);

      break;

    }

    ret += output.substr(at, line_end + 1 - at);

    at = line_end + 1;

  }

  return ret;

}

// 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.

//   regex:    A regular expression object to be applied to

//             the test's captured standard error output; the death test

//             fails if it does not match.

//

// 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 iff 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) {

  if (!spawned())

    return false;

  const String error_message = GetCapturedStderr();

  bool success = false;

  Message buffer;

  buffer << "Death test: " << statement() << "\n";

  switch (outcome()) {

    case LIVED:

      buffer << "    Result: failed to die.\n"

             << " Error msg:\n" << FormatDeathTestOutput(error_message);

      break;

    case THREW:

      buffer << "    Result: threw an exception.\n"

             << " Error msg:\n" << FormatDeathTestOutput(error_message);

      break;

    case RETURNED:

      buffer << "    Result: illegal return in test statement.\n"

             << " Error msg:\n" << FormatDeathTestOutput(error_message);

      break;

    case DIED:

      if (status_ok) {

        const bool matched = RE::PartialMatch(error_message.c_str(), *regex());

        if (matched) {

          success = true;

        } else {

          buffer << "    Result: died but not with expected error.\n"

                 << "  Expected: " << regex()->pattern() << "\n"

                 << "Actual msg:\n" << FormatDeathTestOutput(error_message);

        }

      } else {

        buffer << "    Result: died but not with expected exit code:\n"

               << "            " << ExitSummary(status()) << "\n"

               << "Actual msg:\n" << FormatDeathTestOutput(error_message);

      }

      break;

    case IN_PROGRESS:

    default:

      GTEST_LOG_(FATAL)

          << "DeathTest::Passed somehow called before conclusion of test";

  }

  DeathTest::set_last_death_test_message(buffer.GetString());

  return success;

}

# if 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,

                   const RE* a_regex,

                   const char* file,

                   int line)

      : DeathTestImpl(a_statement, a_regex), 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(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 != NULL) {

    // 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), NULL, 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(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.

      NULL));  // The even is unnamed.

  GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL);

  const String filter_flag = String::Format("--%s%s=%s.%s",

                                            GTEST_FLAG_PREFIX_, kFilterFlag,

                                            info->test_case_name(),

                                            info->name());

  const String internal_flag = String::Format(

    "--%s%s=%s|%d|%d|%u|%Iu|%Iu",

      GTEST_FLAG_PREFIX_,

      kInternalRunDeathTestFlag,

      file_, line_,

      death_test_index,

      static_cast(::GetCurrentProcessId()),

      // size_t has the same with as pointers on both 32-bit and 64-bit

      // Windows platforms.

      // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.

      reinterpret_cast(write_handle),

      reinterpret_cast(event_handle_.Get()));

  char executable_path[_MAX_PATH + 1];  // NOLINT

  GTEST_DEATH_TEST_CHECK_(

      _MAX_PATH + 1 != ::GetModuleFileNameA(NULL,

                                            executable_path,

                                            _MAX_PATH));

  String command_line = String::Format("%s %s \"%s\"",

                                       ::GetCommandLineA(),

                                       filter_flag.c_str(),

                                       internal_flag.c_str());

  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(command_line.c_str()),

      NULL,   // Retuned process handle is not inheritable.

      NULL,   // Retuned thread handle is not inheritable.

      TRUE,   // Child inherits all inheritable handles (for write_handle_).

      0x0,    // Default creation flags.

      NULL,   // 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;

}

# else  // We are not on Windows.

// ForkingDeathTest provides implementations for most of the abstract

// methods of the DeathTest interface.  Only the AssumeRole method is

// left undefined.

class ForkingDeathTest : public DeathTestImpl {

 public:

  ForkingDeathTest(const char* statement, const RE* regex);

  // All of these virtual functions are inherited from DeathTest.

  virtual int Wait();

 protected:

  void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }

 private:

  // PID of child process during death test; 0 in the child process itself.

  pid_t child_pid_;

};

// Constructs a ForkingDeathTest.

ForkingDeathTest::ForkingDeathTest(const char* a_statement, const RE* a_regex)

    : DeathTestImpl(a_statement, a_regex),

      child_pid_(-1) {}

// 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() {

  if (!spawned())

    return 0;

  ReadAndInterpretStatusByte();

  int status_value;

  GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status_value, 0));

  set_status(status_value);

  return status_value;

}

// A concrete death test class that forks, then immediately runs the test

// in the child process.

class NoExecDeathTest : public ForkingDeathTest {

 public:

  NoExecDeathTest(const char* a_statement, const RE* a_regex) :

      ForkingDeathTest(a_statement, a_regex) { }

  virtual TestRole AssumeRole();

};

// 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() {

  const size_t thread_count = GetThreadCount();

  if (thread_count != 1) {

    GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);

  }

  int pipe_fd[2];

  GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);

  DeathTest::set_last_death_test_message("");

  CaptureStderr();

  // When we fork the process below, the log file buffers are copied, but the

  // file descriptors are shared.  We flush all log files here so that closing

  // the file descriptors in the child process doesn't throw off the

  // synchronization between descriptors and buffers in the parent process.

  // This is as close to the fork as possible to avoid a race condition in case

  // there are multiple threads running before the death test, and another

  // thread writes to the log file.

  FlushInfoLog();

  const pid_t child_pid = fork();

  GTEST_DEATH_TEST_CHECK_(child_pid != -1);

  set_child_pid(child_pid);

  if (child_pid == 0) {

    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));

    set_write_fd(pipe_fd[1]);

    // Redirects all logging to stderr in the child process to prevent

    // concurrent writes to the log files.  We capture stderr in the parent

    // process and append the child process' output to a log.

    LogToStderr();

    // Event forwarding to the listeners of event listener API mush be shut

    // down in death test subprocesses.

    GetUnitTestImpl()->listeners()->SuppressEventForwarding();

    return EXECUTE_TEST;

  } else {

    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));

    set_read_fd(pipe_fd[0]);

    set_spawned(true);

    return OVERSEE_TEST;

  }

}

// 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 {

 public:

  ExecDeathTest(const char* a_statement, const RE* a_regex,

                const char* file, int line) :

      ForkingDeathTest(a_statement, a_regex), file_(file), line_(line) { }

  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_;

};

// Utility class for accumulating command-line arguments.

class Arguments {

 public:

  Arguments() {

    args_.push_back(NULL);

  }

  ~Arguments() {

    for (std::vector::iterator i = args_.begin(); i != args_.end();

         ++i) {

      free(*i);

    }

  }

  void AddArgument(const char* argument) {

    args_.insert(args_.end() - 1, posix::StrDup(argument));

  }

  template 

  void AddArguments(const ::std::vector& arguments) {

    for (typename ::std::vector::const_iterator i = arguments.begin();

         i != arguments.end();

         ++i) {

      args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));

    }

  }

  char* const* Argv() {

    return &args_[0];

  }

 private:

  std::vector args_;

};

// A struct that encompasses the arguments to the child process of a

// threadsafe-style death test process.

struct ExecDeathTestArgs {

  char* const* argv;  // Command-line arguments for the child's call to exec

  int close_fd;       // File descriptor to close; the read end of a pipe

};

#  if GTEST_OS_MAC

inline char** GetEnviron() {

  // When Google Test is built as a framework on MacOS X, the environ variable

  // is unavailable. Apple's documentation (man environ) recommends using

  // _NSGetEnviron() instead.

  return *_NSGetEnviron();

}

#  else

// Some POSIX platforms expect you to declare environ. extern "C" makes

// it reside in the global namespace.

extern "C" char** environ;

inline char** GetEnviron() { return environ; }

#  endif  // GTEST_OS_MAC

// 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) {

  ExecDeathTestArgs* const args = static_cast(child_arg);

  GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));

  // We need to execute the test program in the same environment where

  // it was originally invoked.  Therefore we change to the original

  // working directory first.

  const char* const original_dir =

      UnitTest::GetInstance()->original_working_dir();

  // We can safely call chdir() as it's a direct system call.

  if (chdir(original_dir) != 0) {

    DeathTestAbort(String::Format("chdir(\"%s\") failed: %s",

                                  original_dir,

                                  GetLastErrnoDescription().c_str()));

    return EXIT_FAILURE;

  }

  // We can safely call execve() as it's a direct system call.  We

  // cannot use execvp() as it's a libc function and thus potentially

  // unsafe.  Since execve() doesn't search the PATH, the user must

  // invoke the test program via a valid path that contains at least

  // one path separator.

  execve(args->argv[0], args->argv, GetEnviron());

  DeathTestAbort(String::Format("execve(%s, ...) in %s failed: %s",

                                args->argv[0],

                                original_dir,

                                GetLastErrnoDescription().c_str()));

  return EXIT_FAILURE;

}

// 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.

bool StackLowerThanAddress(const void* ptr) GTEST_NO_INLINE_;

bool StackLowerThanAddress(const void* ptr) {

  int dummy;

  return &dummy < ptr;

}

bool StackGrowsDown() {

  int dummy;

  return StackLowerThanAddress(&dummy);

}

// A threadsafe implementation of fork(2) for threadsafe-style death tests

// that uses clone(2).  It dies with an error message if anything goes

// wrong.

static pid_t ExecDeathTestFork(char* const* argv, int close_fd) {

  ExecDeathTestArgs args = { argv, close_fd };

  pid_t child_pid = -1;

#  if GTEST_HAS_CLONE

  const bool use_fork = GTEST_FLAG(death_test_use_fork);

  if (!use_fork) {

    static const bool stack_grows_down = StackGrowsDown();

    const size_t stack_size = getpagesize();

    // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.

    void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,

                             MAP_ANON | MAP_PRIVATE, -1, 0);

    GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);

    void* const stack_top =

        static_cast(stack) + (stack_grows_down ? stack_size : 0);

    child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);

    GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);

  }

#  else

  const bool use_fork = true;

#  endif  // GTEST_HAS_CLONE

  if (use_fork && (child_pid = fork()) == 0) {

      ExecDeathTestChildMain(&args);

      _exit(0);

  }

  GTEST_DEATH_TEST_CHECK_(child_pid != -1);

  return child_pid;

}

// 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() {

  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 != NULL) {

    set_write_fd(flag->write_fd());

    return EXECUTE_TEST;

  }

  int pipe_fd[2];

  GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);

  // Clear the close-on-exec flag on the write end of the pipe, lest

  // it be closed when the child process does an exec:

  GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);

  const String filter_flag =

      String::Format("--%s%s=%s.%s",

                     GTEST_FLAG_PREFIX_, kFilterFlag,

                     info->test_case_name(), info->name());

  const String internal_flag =

      String::Format("--%s%s=%s|%d|%d|%d",

                     GTEST_FLAG_PREFIX_, kInternalRunDeathTestFlag,

                     file_, line_, death_test_index, pipe_fd[1]);

  Arguments args;

  args.AddArguments(GetArgvs());

  args.AddArgument(filter_flag.c_str());

  args.AddArgument(internal_flag.c_str());

  DeathTest::set_last_death_test_message("");

  CaptureStderr();

  // See the comment in NoExecDeathTest::AssumeRole for why the next line

  // is necessary.

  FlushInfoLog();

  const pid_t child_pid = ExecDeathTestFork(args.Argv(), pipe_fd[0]);

  GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));

  set_child_pid(child_pid);

  set_read_fd(pipe_fd[0]);

  set_spawned(true);

  return OVERSEE_TEST;

}

# 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, const RE* regex,

                                     const char* file, int line,

                                     DeathTest** test) {

  UnitTestImpl* const impl = GetUnitTestImpl();

  const InternalRunDeathTestFlag* const flag =

      impl->internal_run_death_test_flag();

  const int death_test_index = impl->current_test_info()

      ->increment_death_test_count();

  if (flag != NULL) {

    if (death_test_index > flag->index()) {

      DeathTest::set_last_death_test_message(String::Format(

          "Death test count (%d) somehow exceeded expected maximum (%d)",

          death_test_index, flag->index()));

      return false;

    }

    if (!(flag->file() == file && flag->line() == line &&

          flag->index() == death_test_index)) {

      *test = NULL;

      return true;

    }

  }

# if GTEST_OS_WINDOWS

  if (GTEST_FLAG(death_test_style) == "threadsafe" ||

      GTEST_FLAG(death_test_style) == "fast") {

    *test = new WindowsDeathTest(statement, regex, file, line);

  }

# else

  if (GTEST_FLAG(death_test_style) == "threadsafe") {

    *test = new ExecDeathTest(statement, regex, file, line);

  } else if (GTEST_FLAG(death_test_style) == "fast") {

    *test = new NoExecDeathTest(statement, regex);

  }

# endif  // GTEST_OS_WINDOWS

  else {  // NOLINT - this is more readable than unbalanced brackets inside #if.

    DeathTest::set_last_death_test_message(String::Format(

        "Unknown death test style \"%s\" encountered",

        GTEST_FLAG(death_test_style).c_str()));

    return false;

  }

  return true;

}

// Splits a given string on a given delimiter, populating a given

// vector with the fields.  GTEST_HAS_DEATH_TEST implies that we have

// ::std::string, so we can use it here.

static void SplitString(const ::std::string& str, char delimiter,

                        ::std::vector< ::std::string>* dest) {

  ::std::vector< ::std::string> parsed;

  ::std::string::size_type pos = 0;

  while (::testing::internal::AlwaysTrue()) {

    const ::std::string::size_type colon = str.find(delimiter, pos);

    if (colon == ::std::string::npos) {

      parsed.push_back(str.substr(pos));

      break;

    } else {

      parsed.push_back(str.substr(pos, colon - pos));

      pos = colon + 1;

    }

  }

  dest->swap(parsed);

}

# if 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.

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(String::Format("Unable to open parent process %u",