1// Copyright 2005, Google Inc.
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29//
30// Author: wan@google.com (Zhanyong Wan), vladl@google.com (Vlad Losev)
31//
32// This file implements death tests.
33
34#include "gtest/gtest-death-test.h"
35#include "gtest/internal/gtest-port.h"
36
37#if GTEST_HAS_DEATH_TEST
38
39# if GTEST_OS_MAC
40#  include <crt_externs.h>
41# endif  // GTEST_OS_MAC
42
43# include <errno.h>
44# include <fcntl.h>
45# include <limits.h>
46
47# if GTEST_OS_LINUX
48#  include <signal.h>
49# endif  // GTEST_OS_LINUX
50
51# include <stdarg.h>
52
53# if GTEST_OS_WINDOWS
54#  include <windows.h>
55# else
56#  include <sys/mman.h>
57#  include <sys/wait.h>
58# endif  // GTEST_OS_WINDOWS
59
60# if GTEST_OS_QNX
61#  include <spawn.h>
62# endif  // GTEST_OS_QNX
63
64#endif  // GTEST_HAS_DEATH_TEST
65
66#include "gtest/gtest-message.h"
67#include "gtest/internal/gtest-string.h"
68
69// Indicates that this translation unit is part of Google Test's
70// implementation.  It must come before gtest-internal-inl.h is
71// included, or there will be a compiler error.  This trick is to
72// prevent a user from accidentally including gtest-internal-inl.h in
73// his code.
74#define GTEST_IMPLEMENTATION_ 1
75#include "src/gtest-internal-inl.h"
76#undef GTEST_IMPLEMENTATION_
77
78namespace testing {
79
80// Constants.
81
82// The default death test style.
83static const char kDefaultDeathTestStyle[] = "fast";
84
85GTEST_DEFINE_string_(
86    death_test_style,
87    internal::StringFromGTestEnv("death_test_style", kDefaultDeathTestStyle),
88    "Indicates how to run a death test in a forked child process: "
89    "\"threadsafe\" (child process re-executes the test binary "
90    "from the beginning, running only the specific death test) or "
91    "\"fast\" (child process runs the death test immediately "
92    "after forking).");
93
94GTEST_DEFINE_bool_(
95    death_test_use_fork,
96    internal::BoolFromGTestEnv("death_test_use_fork", false),
97    "Instructs to use fork()/_exit() instead of clone() in death tests. "
98    "Ignored and always uses fork() on POSIX systems where clone() is not "
99    "implemented. Useful when running under valgrind or similar tools if "
100    "those do not support clone(). Valgrind 3.3.1 will just fail if "
101    "it sees an unsupported combination of clone() flags. "
102    "It is not recommended to use this flag w/o valgrind though it will "
103    "work in 99% of the cases. Once valgrind is fixed, this flag will "
104    "most likely be removed.");
105
106namespace internal {
107GTEST_DEFINE_string_(
108    internal_run_death_test, "",
109    "Indicates the file, line number, temporal index of "
110    "the single death test to run, and a file descriptor to "
111    "which a success code may be sent, all separated by "
112    "the '|' characters.  This flag is specified if and only if the current "
113    "process is a sub-process launched for running a thread-safe "
114    "death test.  FOR INTERNAL USE ONLY.");
115}  // namespace internal
116
117#if GTEST_HAS_DEATH_TEST
118
119namespace internal {
120
121// Valid only for fast death tests. Indicates the code is running in the
122// child process of a fast style death test.
123static bool g_in_fast_death_test_child = false;
124
125// Returns a Boolean value indicating whether the caller is currently
126// executing in the context of the death test child process.  Tools such as
127// Valgrind heap checkers may need this to modify their behavior in death
128// tests.  IMPORTANT: This is an internal utility.  Using it may break the
129// implementation of death tests.  User code MUST NOT use it.
130bool InDeathTestChild() {
131# if GTEST_OS_WINDOWS
132
133  // On Windows, death tests are thread-safe regardless of the value of the
134  // death_test_style flag.
135  return !GTEST_FLAG(internal_run_death_test).empty();
136
137# else
138
139  if (GTEST_FLAG(death_test_style) == "threadsafe")
140    return !GTEST_FLAG(internal_run_death_test).empty();
141  else
142    return g_in_fast_death_test_child;
143#endif
144}
145
146}  // namespace internal
147
148// ExitedWithCode constructor.
149ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
150}
151
152// ExitedWithCode function-call operator.
153bool ExitedWithCode::operator()(int exit_status) const {
154# if GTEST_OS_WINDOWS
155
156  return exit_status == exit_code_;
157
158# else
159
160  return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;
161
162# endif  // GTEST_OS_WINDOWS
163}
164
165# if !GTEST_OS_WINDOWS
166// KilledBySignal constructor.
167KilledBySignal::KilledBySignal(int signum) : signum_(signum) {
168}
169
170// KilledBySignal function-call operator.
171bool KilledBySignal::operator()(int exit_status) const {
172  return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;
173}
174# endif  // !GTEST_OS_WINDOWS
175
176namespace internal {
177
178// Utilities needed for death tests.
179
180// Generates a textual description of a given exit code, in the format
181// specified by wait(2).
182static std::string ExitSummary(int exit_code) {
183  Message m;
184
185# if GTEST_OS_WINDOWS
186
187  m << "Exited with exit status " << exit_code;
188
189# else
190
191  if (WIFEXITED(exit_code)) {
192    m << "Exited with exit status " << WEXITSTATUS(exit_code);
193  } else if (WIFSIGNALED(exit_code)) {
194    m << "Terminated by signal " << WTERMSIG(exit_code);
195  }
196#  ifdef WCOREDUMP
197  if (WCOREDUMP(exit_code)) {
198    m << " (core dumped)";
199  }
200#  endif
201# endif  // GTEST_OS_WINDOWS
202
203  return m.GetString();
204}
205
206// Returns true if exit_status describes a process that was terminated
207// by a signal, or exited normally with a nonzero exit code.
208bool ExitedUnsuccessfully(int exit_status) {
209  return !ExitedWithCode(0)(exit_status);
210}
211
212# if !GTEST_OS_WINDOWS
213// Generates a textual failure message when a death test finds more than
214// one thread running, or cannot determine the number of threads, prior
215// to executing the given statement.  It is the responsibility of the
216// caller not to pass a thread_count of 1.
217static std::string DeathTestThreadWarning(size_t thread_count) {
218  Message msg;
219  msg << "Death tests use fork(), which is unsafe particularly"
220      << " in a threaded context. For this test, " << GTEST_NAME_ << " ";
221  if (thread_count == 0)
222    msg << "couldn't detect the number of threads.";
223  else
224    msg << "detected " << thread_count << " threads.";
225  return msg.GetString();
226}
227# endif  // !GTEST_OS_WINDOWS
228
229// Flag characters for reporting a death test that did not die.
230static const char kDeathTestLived = 'L';
231static const char kDeathTestReturned = 'R';
232static const char kDeathTestThrew = 'T';
233static const char kDeathTestInternalError = 'I';
234
235// An enumeration describing all of the possible ways that a death test can
236// conclude.  DIED means that the process died while executing the test
237// code; LIVED means that process lived beyond the end of the test code;
238// RETURNED means that the test statement attempted to execute a return
239// statement, which is not allowed; THREW means that the test statement
240// returned control by throwing an exception.  IN_PROGRESS means the test
241// has not yet concluded.
242// TODO(vladl@google.com): Unify names and possibly values for
243// AbortReason, DeathTestOutcome, and flag characters above.
244enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED, THREW };
245
246// Routine for aborting the program which is safe to call from an
247// exec-style death test child process, in which case the error
248// message is propagated back to the parent process.  Otherwise, the
249// message is simply printed to stderr.  In either case, the program
250// then exits with status 1.
251void DeathTestAbort(const std::string& message) {
252  // On a POSIX system, this function may be called from a threadsafe-style
253  // death test child process, which operates on a very small stack.  Use
254  // the heap for any additional non-minuscule memory requirements.
255  const InternalRunDeathTestFlag* const flag =
256      GetUnitTestImpl()->internal_run_death_test_flag();
257  if (flag != NULL) {
258    FILE* parent = posix::FDOpen(flag->write_fd(), "w");
259    fputc(kDeathTestInternalError, parent);
260    fprintf(parent, "%s", message.c_str());
261    fflush(parent);
262    _exit(1);
263  } else {
264    fprintf(stderr, "%s", message.c_str());
265    fflush(stderr);
266    posix::Abort();
267  }
268}
269
270// A replacement for CHECK that calls DeathTestAbort if the assertion
271// fails.
272# define GTEST_DEATH_TEST_CHECK_(expression) \
273  do { \
274    if (!::testing::internal::IsTrue(expression)) { \
275      DeathTestAbort( \
276          ::std::string("CHECK failed: File ") + __FILE__ +  ", line " \
277          + ::testing::internal::StreamableToString(__LINE__) + ": " \
278          + #expression); \
279    } \
280  } while (::testing::internal::AlwaysFalse())
281
282// This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
283// evaluating any system call that fulfills two conditions: it must return
284// -1 on failure, and set errno to EINTR when it is interrupted and
285// should be tried again.  The macro expands to a loop that repeatedly
286// evaluates the expression as long as it evaluates to -1 and sets
287// errno to EINTR.  If the expression evaluates to -1 but errno is
288// something other than EINTR, DeathTestAbort is called.
289# define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \
290  do { \
291    int gtest_retval; \
292    do { \
293      gtest_retval = (expression); \
294    } while (gtest_retval == -1 && errno == EINTR); \
295    if (gtest_retval == -1) { \
296      DeathTestAbort( \
297          ::std::string("CHECK failed: File ") + __FILE__ + ", line " \
298          + ::testing::internal::StreamableToString(__LINE__) + ": " \
299          + #expression + " != -1"); \
300    } \
301  } while (::testing::internal::AlwaysFalse())
302
303// Returns the message describing the last system error in errno.
304std::string GetLastErrnoDescription() {
305    return errno == 0 ? "" : posix::StrError(errno);
306}
307
308// This is called from a death test parent process to read a failure
309// message from the death test child process and log it with the FATAL
310// severity. On Windows, the message is read from a pipe handle. On other
311// platforms, it is read from a file descriptor.
312static void FailFromInternalError(int fd) {
313  Message error;
314  char buffer[256];
315  int num_read;
316
317  do {
318    while ((num_read = posix::Read(fd, buffer, 255)) > 0) {
319      buffer[num_read] = '\0';
320      error << buffer;
321    }
322  } while (num_read == -1 && errno == EINTR);
323
324  if (num_read == 0) {
325    GTEST_LOG_(FATAL) << error.GetString();
326  } else {
327    const int last_error = errno;
328    GTEST_LOG_(FATAL) << "Error while reading death test internal: "
329                      << GetLastErrnoDescription() << " [" << last_error << "]";
330  }
331}
332
333// Death test constructor.  Increments the running death test count
334// for the current test.
335DeathTest::DeathTest() {
336  TestInfo* const info = GetUnitTestImpl()->current_test_info();
337  if (info == NULL) {
338    DeathTestAbort("Cannot run a death test outside of a TEST or "
339                   "TEST_F construct");
340  }
341}
342
343// Creates and returns a death test by dispatching to the current
344// death test factory.
345bool DeathTest::Create(const char* statement, const RE* regex,
346                       const char* file, int line, DeathTest** test) {
347  return GetUnitTestImpl()->death_test_factory()->Create(
348      statement, regex, file, line, test);
349}
350
351const char* DeathTest::LastMessage() {
352  return last_death_test_message_.c_str();
353}
354
355void DeathTest::set_last_death_test_message(const std::string& message) {
356  last_death_test_message_ = message;
357}
358
359std::string DeathTest::last_death_test_message_;
360
361// Provides cross platform implementation for some death functionality.
362class DeathTestImpl : public DeathTest {
363 protected:
364  DeathTestImpl(const char* a_statement, const RE* a_regex)
365      : statement_(a_statement),
366        regex_(a_regex),
367        spawned_(false),
368        status_(-1),
369        outcome_(IN_PROGRESS),
370        read_fd_(-1),
371        write_fd_(-1) {}
372
373  // read_fd_ is expected to be closed and cleared by a derived class.
374  ~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }
375
376  void Abort(AbortReason reason);
377  virtual bool Passed(bool status_ok);
378
379  const char* statement() const { return statement_; }
380  const RE* regex() const { return regex_; }
381  bool spawned() const { return spawned_; }
382  void set_spawned(bool is_spawned) { spawned_ = is_spawned; }
383  int status() const { return status_; }
384  void set_status(int a_status) { status_ = a_status; }
385  DeathTestOutcome outcome() const { return outcome_; }
386  void set_outcome(DeathTestOutcome an_outcome) { outcome_ = an_outcome; }
387  int read_fd() const { return read_fd_; }
388  void set_read_fd(int fd) { read_fd_ = fd; }
389  int write_fd() const { return write_fd_; }
390  void set_write_fd(int fd) { write_fd_ = fd; }
391
392  // Called in the parent process only. Reads the result code of the death
393  // test child process via a pipe, interprets it to set the outcome_
394  // member, and closes read_fd_.  Outputs diagnostics and terminates in
395  // case of unexpected codes.
396  void ReadAndInterpretStatusByte();
397
398 private:
399  // The textual content of the code this object is testing.  This class
400  // doesn't own this string and should not attempt to delete it.
401  const char* const statement_;
402  // The regular expression which test output must match.  DeathTestImpl
403  // doesn't own this object and should not attempt to delete it.
404  const RE* const regex_;
405  // True if the death test child process has been successfully spawned.
406  bool spawned_;
407  // The exit status of the child process.
408  int status_;
409  // How the death test concluded.
410  DeathTestOutcome outcome_;
411  // Descriptor to the read end of the pipe to the child process.  It is
412  // always -1 in the child process.  The child keeps its write end of the
413  // pipe in write_fd_.
414  int read_fd_;
415  // Descriptor to the child's write end of the pipe to the parent process.
416  // It is always -1 in the parent process.  The parent keeps its end of the
417  // pipe in read_fd_.
418  int write_fd_;
419};
420
421// Called in the parent process only. Reads the result code of the death
422// test child process via a pipe, interprets it to set the outcome_
423// member, and closes read_fd_.  Outputs diagnostics and terminates in
424// case of unexpected codes.
425void DeathTestImpl::ReadAndInterpretStatusByte() {
426  char flag;
427  int bytes_read;
428
429  // The read() here blocks until data is available (signifying the
430  // failure of the death test) or until the pipe is closed (signifying
431  // its success), so it's okay to call this in the parent before
432  // the child process has exited.
433  do {
434    bytes_read = posix::Read(read_fd(), &flag, 1);
435  } while (bytes_read == -1 && errno == EINTR);
436
437  if (bytes_read == 0) {
438    set_outcome(DIED);
439  } else if (bytes_read == 1) {
440    switch (flag) {
441      case kDeathTestReturned:
442        set_outcome(RETURNED);
443        break;
444      case kDeathTestThrew:
445        set_outcome(THREW);
446        break;
447      case kDeathTestLived:
448        set_outcome(LIVED);
449        break;
450      case kDeathTestInternalError:
451        FailFromInternalError(read_fd());  // Does not return.
452        break;
453      default:
454        GTEST_LOG_(FATAL) << "Death test child process reported "
455                          << "unexpected status byte ("
456                          << static_cast<unsigned int>(flag) << ")";
457    }
458  } else {
459    GTEST_LOG_(FATAL) << "Read from death test child process failed: "
460                      << GetLastErrnoDescription();
461  }
462  GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));
463  set_read_fd(-1);
464}
465
466// Signals that the death test code which should have exited, didn't.
467// Should be called only in a death test child process.
468// Writes a status byte to the child's status file descriptor, then
469// calls _exit(1).
470void DeathTestImpl::Abort(AbortReason reason) {
471  // The parent process considers the death test to be a failure if
472  // it finds any data in our pipe.  So, here we write a single flag byte
473  // to the pipe, then exit.
474  const char status_ch =
475      reason == TEST_DID_NOT_DIE ? kDeathTestLived :
476      reason == TEST_THREW_EXCEPTION ? kDeathTestThrew : kDeathTestReturned;
477
478  GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));
479  // We are leaking the descriptor here because on some platforms (i.e.,
480  // when built as Windows DLL), destructors of global objects will still
481  // run after calling _exit(). On such systems, write_fd_ will be
482  // indirectly closed from the destructor of UnitTestImpl, causing double
483  // close if it is also closed here. On debug configurations, double close
484  // may assert. As there are no in-process buffers to flush here, we are
485  // relying on the OS to close the descriptor after the process terminates
486  // when the destructors are not run.
487  _exit(1);  // Exits w/o any normal exit hooks (we were supposed to crash)
488}
489
490// Returns an indented copy of stderr output for a death test.
491// This makes distinguishing death test output lines from regular log lines
492// much easier.
493static ::std::string FormatDeathTestOutput(const ::std::string& output) {
494  ::std::string ret;
495  for (size_t at = 0; ; ) {
496    const size_t line_end = output.find('\n', at);
497    ret += "[  DEATH   ] ";
498    if (line_end == ::std::string::npos) {
499      ret += output.substr(at);
500      break;
501    }
502    ret += output.substr(at, line_end + 1 - at);
503    at = line_end + 1;
504  }
505  return ret;
506}
507
508// Assesses the success or failure of a death test, using both private
509// members which have previously been set, and one argument:
510//
511// Private data members:
512//   outcome:  An enumeration describing how the death test
513//             concluded: DIED, LIVED, THREW, or RETURNED.  The death test
514//             fails in the latter three cases.
515//   status:   The exit status of the child process. On *nix, it is in the
516//             in the format specified by wait(2). On Windows, this is the
517//             value supplied to the ExitProcess() API or a numeric code
518//             of the exception that terminated the program.
519//   regex:    A regular expression object to be applied to
520//             the test's captured standard error output; the death test
521//             fails if it does not match.
522//
523// Argument:
524//   status_ok: true if exit_status is acceptable in the context of
525//              this particular death test, which fails if it is false
526//
527// Returns true iff all of the above conditions are met.  Otherwise, the
528// first failing condition, in the order given above, is the one that is
529// reported. Also sets the last death test message string.
530bool DeathTestImpl::Passed(bool status_ok) {
531  if (!spawned())
532    return false;
533
534  const std::string error_message = GetCapturedStderr();
535
536  bool success = false;
537  Message buffer;
538
539  buffer << "Death test: " << statement() << "\n";
540  switch (outcome()) {
541    case LIVED:
542      buffer << "    Result: failed to die.\n"
543             << " Error msg:\n" << FormatDeathTestOutput(error_message);
544      break;
545    case THREW:
546      buffer << "    Result: threw an exception.\n"
547             << " Error msg:\n" << FormatDeathTestOutput(error_message);
548      break;
549    case RETURNED:
550      buffer << "    Result: illegal return in test statement.\n"
551             << " Error msg:\n" << FormatDeathTestOutput(error_message);
552      break;
553    case DIED:
554      if (status_ok) {
555        const bool matched = RE::PartialMatch(error_message.c_str(), *regex());
556        if (matched) {
557          success = true;
558        } else {
559          buffer << "    Result: died but not with expected error.\n"
560                 << "  Expected: " << regex()->pattern() << "\n"
561                 << "Actual msg:\n" << FormatDeathTestOutput(error_message);
562        }
563      } else {
564        buffer << "    Result: died but not with expected exit code:\n"
565               << "            " << ExitSummary(status()) << "\n"
566               << "Actual msg:\n" << FormatDeathTestOutput(error_message);
567      }
568      break;
569    case IN_PROGRESS:
570    default:
571      GTEST_LOG_(FATAL)
572          << "DeathTest::Passed somehow called before conclusion of test";
573  }
574
575  DeathTest::set_last_death_test_message(buffer.GetString());
576  return success;
577}
578
579# if GTEST_OS_WINDOWS
580// WindowsDeathTest implements death tests on Windows. Due to the
581// specifics of starting new processes on Windows, death tests there are
582// always threadsafe, and Google Test considers the
583// --gtest_death_test_style=fast setting to be equivalent to
584// --gtest_death_test_style=threadsafe there.
585//
586// A few implementation notes:  Like the Linux version, the Windows
587// implementation uses pipes for child-to-parent communication. But due to
588// the specifics of pipes on Windows, some extra steps are required:
589//
590// 1. The parent creates a communication pipe and stores handles to both
591//    ends of it.
592// 2. The parent starts the child and provides it with the information
593//    necessary to acquire the handle to the write end of the pipe.
594// 3. The child acquires the write end of the pipe and signals the parent
595//    using a Windows event.
596// 4. Now the parent can release the write end of the pipe on its side. If
597//    this is done before step 3, the object's reference count goes down to
598//    0 and it is destroyed, preventing the child from acquiring it. The
599//    parent now has to release it, or read operations on the read end of
600//    the pipe will not return when the child terminates.
601// 5. The parent reads child's output through the pipe (outcome code and
602//    any possible error messages) from the pipe, and its stderr and then
603//    determines whether to fail the test.
604//
605// Note: to distinguish Win32 API calls from the local method and function
606// calls, the former are explicitly resolved in the global namespace.
607//
608class WindowsDeathTest : public DeathTestImpl {
609 public:
610  WindowsDeathTest(const char* a_statement,
611                   const RE* a_regex,
612                   const char* file,
613                   int line)
614      : DeathTestImpl(a_statement, a_regex), file_(file), line_(line) {}
615
616  // All of these virtual functions are inherited from DeathTest.
617  virtual int Wait();
618  virtual TestRole AssumeRole();
619
620 private:
621  // The name of the file in which the death test is located.
622  const char* const file_;
623  // The line number on which the death test is located.
624  const int line_;
625  // Handle to the write end of the pipe to the child process.
626  AutoHandle write_handle_;
627  // Child process handle.
628  AutoHandle child_handle_;
629  // Event the child process uses to signal the parent that it has
630  // acquired the handle to the write end of the pipe. After seeing this
631  // event the parent can release its own handles to make sure its
632  // ReadFile() calls return when the child terminates.
633  AutoHandle event_handle_;
634};
635
636// Waits for the child in a death test to exit, returning its exit
637// status, or 0 if no child process exists.  As a side effect, sets the
638// outcome data member.
639int WindowsDeathTest::Wait() {
640  if (!spawned())
641    return 0;
642
643  // Wait until the child either signals that it has acquired the write end
644  // of the pipe or it dies.
645  const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() };
646  switch (::WaitForMultipleObjects(2,
647                                   wait_handles,
648                                   FALSE,  // Waits for any of the handles.
649                                   INFINITE)) {
650    case WAIT_OBJECT_0:
651    case WAIT_OBJECT_0 + 1:
652      break;
653    default:
654      GTEST_DEATH_TEST_CHECK_(false);  // Should not get here.
655  }
656
657  // The child has acquired the write end of the pipe or exited.
658  // We release the handle on our side and continue.
659  write_handle_.Reset();
660  event_handle_.Reset();
661
662  ReadAndInterpretStatusByte();
663
664  // Waits for the child process to exit if it haven't already. This
665  // returns immediately if the child has already exited, regardless of
666  // whether previous calls to WaitForMultipleObjects synchronized on this
667  // handle or not.
668  GTEST_DEATH_TEST_CHECK_(
669      WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(),
670                                             INFINITE));
671  DWORD status_code;
672  GTEST_DEATH_TEST_CHECK_(
673      ::GetExitCodeProcess(child_handle_.Get(), &status_code) != FALSE);
674  child_handle_.Reset();
675  set_status(static_cast<int>(status_code));
676  return status();
677}
678
679// The AssumeRole process for a Windows death test.  It creates a child
680// process with the same executable as the current process to run the
681// death test.  The child process is given the --gtest_filter and
682// --gtest_internal_run_death_test flags such that it knows to run the
683// current death test only.
684DeathTest::TestRole WindowsDeathTest::AssumeRole() {
685  const UnitTestImpl* const impl = GetUnitTestImpl();
686  const InternalRunDeathTestFlag* const flag =
687      impl->internal_run_death_test_flag();
688  const TestInfo* const info = impl->current_test_info();
689  const int death_test_index = info->result()->death_test_count();
690
691  if (flag != NULL) {
692    // ParseInternalRunDeathTestFlag() has performed all the necessary
693    // processing.
694    set_write_fd(flag->write_fd());
695    return EXECUTE_TEST;
696  }
697
698  // WindowsDeathTest uses an anonymous pipe to communicate results of
699  // a death test.
700  SECURITY_ATTRIBUTES handles_are_inheritable = {
701    sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
702  HANDLE read_handle, write_handle;
703  GTEST_DEATH_TEST_CHECK_(
704      ::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable,
705                   0)  // Default buffer size.
706      != FALSE);
707  set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle),
708                                O_RDONLY));
709  write_handle_.Reset(write_handle);
710  event_handle_.Reset(::CreateEvent(
711      &handles_are_inheritable,
712      TRUE,    // The event will automatically reset to non-signaled state.
713      FALSE,   // The initial state is non-signalled.
714      NULL));  // The even is unnamed.
715  GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL);
716  const std::string filter_flag =
717      std::string("--") + GTEST_FLAG_PREFIX_ + kFilterFlag + "=" +
718      info->test_case_name() + "." + info->name();
719  const std::string internal_flag =
720      std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag +
721      "=" + file_ + "|" + StreamableToString(line_) + "|" +
722      StreamableToString(death_test_index) + "|" +
723      StreamableToString(static_cast<unsigned int>(::GetCurrentProcessId())) +
724      // size_t has the same width as pointers on both 32-bit and 64-bit
725      // Windows platforms.
726      // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
727      "|" + StreamableToString(reinterpret_cast<size_t>(write_handle)) +
728      "|" + StreamableToString(reinterpret_cast<size_t>(event_handle_.Get()));
729
730  char executable_path[_MAX_PATH + 1];  // NOLINT
731  GTEST_DEATH_TEST_CHECK_(
732      _MAX_PATH + 1 != ::GetModuleFileNameA(NULL,
733                                            executable_path,
734                                            _MAX_PATH));
735
736  std::string command_line =
737      std::string(::GetCommandLineA()) + " " + filter_flag + " \"" +
738      internal_flag + "\"";
739
740  DeathTest::set_last_death_test_message("");
741
742  CaptureStderr();
743  // Flush the log buffers since the log streams are shared with the child.
744  FlushInfoLog();
745
746  // The child process will share the standard handles with the parent.
747  STARTUPINFOA startup_info;
748  memset(&startup_info, 0, sizeof(STARTUPINFO));
749  startup_info.dwFlags = STARTF_USESTDHANDLES;
750  startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
751  startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
752  startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);
753
754  PROCESS_INFORMATION process_info;
755  GTEST_DEATH_TEST_CHECK_(::CreateProcessA(
756      executable_path,
757      const_cast<char*>(command_line.c_str()),
758      NULL,   // Retuned process handle is not inheritable.
759      NULL,   // Retuned thread handle is not inheritable.
760      TRUE,   // Child inherits all inheritable handles (for write_handle_).
761      0x0,    // Default creation flags.
762      NULL,   // Inherit the parent's environment.
763      UnitTest::GetInstance()->original_working_dir(),
764      &startup_info,
765      &process_info) != FALSE);
766  child_handle_.Reset(process_info.hProcess);
767  ::CloseHandle(process_info.hThread);
768  set_spawned(true);
769  return OVERSEE_TEST;
770}
771# else  // We are not on Windows.
772
773// ForkingDeathTest provides implementations for most of the abstract
774// methods of the DeathTest interface.  Only the AssumeRole method is
775// left undefined.
776class ForkingDeathTest : public DeathTestImpl {
777 public:
778  ForkingDeathTest(const char* statement, const RE* regex);
779
780  // All of these virtual functions are inherited from DeathTest.
781  virtual int Wait();
782
783 protected:
784  void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }
785
786 private:
787  // PID of child process during death test; 0 in the child process itself.
788  pid_t child_pid_;
789};
790
791// Constructs a ForkingDeathTest.
792ForkingDeathTest::ForkingDeathTest(const char* a_statement, const RE* a_regex)
793    : DeathTestImpl(a_statement, a_regex),
794      child_pid_(-1) {}
795
796// Waits for the child in a death test to exit, returning its exit
797// status, or 0 if no child process exists.  As a side effect, sets the
798// outcome data member.
799int ForkingDeathTest::Wait() {
800  if (!spawned())
801    return 0;
802
803  ReadAndInterpretStatusByte();
804
805  int status_value;
806  GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status_value, 0));
807  set_status(status_value);
808  return status_value;
809}
810
811// A concrete death test class that forks, then immediately runs the test
812// in the child process.
813class NoExecDeathTest : public ForkingDeathTest {
814 public:
815  NoExecDeathTest(const char* a_statement, const RE* a_regex) :
816      ForkingDeathTest(a_statement, a_regex) { }
817  virtual TestRole AssumeRole();
818};
819
820// The AssumeRole process for a fork-and-run death test.  It implements a
821// straightforward fork, with a simple pipe to transmit the status byte.
822DeathTest::TestRole NoExecDeathTest::AssumeRole() {
823  const size_t thread_count = GetThreadCount();
824  if (thread_count != 1) {
825    GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);
826  }
827
828  int pipe_fd[2];
829  GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
830
831  DeathTest::set_last_death_test_message("");
832  CaptureStderr();
833  // When we fork the process below, the log file buffers are copied, but the
834  // file descriptors are shared.  We flush all log files here so that closing
835  // the file descriptors in the child process doesn't throw off the
836  // synchronization between descriptors and buffers in the parent process.
837  // This is as close to the fork as possible to avoid a race condition in case
838  // there are multiple threads running before the death test, and another
839  // thread writes to the log file.
840  FlushInfoLog();
841
842  const pid_t child_pid = fork();
843  GTEST_DEATH_TEST_CHECK_(child_pid != -1);
844  set_child_pid(child_pid);
845  if (child_pid == 0) {
846    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));
847    set_write_fd(pipe_fd[1]);
848    // Redirects all logging to stderr in the child process to prevent
849    // concurrent writes to the log files.  We capture stderr in the parent
850    // process and append the child process' output to a log.
851    LogToStderr();
852    // Event forwarding to the listeners of event listener API mush be shut
853    // down in death test subprocesses.
854    GetUnitTestImpl()->listeners()->SuppressEventForwarding();
855    g_in_fast_death_test_child = true;
856    return EXECUTE_TEST;
857  } else {
858    GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
859    set_read_fd(pipe_fd[0]);
860    set_spawned(true);
861    return OVERSEE_TEST;
862  }
863}
864
865// A concrete death test class that forks and re-executes the main
866// program from the beginning, with command-line flags set that cause
867// only this specific death test to be run.
868class ExecDeathTest : public ForkingDeathTest {
869 public:
870  ExecDeathTest(const char* a_statement, const RE* a_regex,
871                const char* file, int line) :
872      ForkingDeathTest(a_statement, a_regex), file_(file), line_(line) { }
873  virtual TestRole AssumeRole();
874 private:
875  static ::std::vector<testing::internal::string>
876  GetArgvsForDeathTestChildProcess() {
877    ::std::vector<testing::internal::string> args = GetInjectableArgvs();
878    return args;
879  }
880  // The name of the file in which the death test is located.
881  const char* const file_;
882  // The line number on which the death test is located.
883  const int line_;
884};
885
886// Utility class for accumulating command-line arguments.
887class Arguments {
888 public:
889  Arguments() {
890    args_.push_back(NULL);
891  }
892
893  ~Arguments() {
894    for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
895         ++i) {
896      free(*i);
897    }
898  }
899  void AddArgument(const char* argument) {
900    args_.insert(args_.end() - 1, posix::StrDup(argument));
901  }
902
903  template <typename Str>
904  void AddArguments(const ::std::vector<Str>& arguments) {
905    for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
906         i != arguments.end();
907         ++i) {
908      args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));
909    }
910  }
911  char* const* Argv() {
912    return &args_[0];
913  }
914
915 private:
916  std::vector<char*> args_;
917};
918
919// A struct that encompasses the arguments to the child process of a
920// threadsafe-style death test process.
921struct ExecDeathTestArgs {
922  char* const* argv;  // Command-line arguments for the child's call to exec
923  int close_fd;       // File descriptor to close; the read end of a pipe
924};
925
926#  if GTEST_OS_MAC
927inline char** GetEnviron() {
928  // When Google Test is built as a framework on MacOS X, the environ variable
929  // is unavailable. Apple's documentation (man environ) recommends using
930  // _NSGetEnviron() instead.
931  return *_NSGetEnviron();
932}
933#  else
934// Some POSIX platforms expect you to declare environ. extern "C" makes
935// it reside in the global namespace.
936extern "C" char** environ;
937inline char** GetEnviron() { return environ; }
938#  endif  // GTEST_OS_MAC
939
940#  if !GTEST_OS_QNX
941// The main function for a threadsafe-style death test child process.
942// This function is called in a clone()-ed process and thus must avoid
943// any potentially unsafe operations like malloc or libc functions.
944static int ExecDeathTestChildMain(void* child_arg) {
945  ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg);
946  GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));
947
948  // We need to execute the test program in the same environment where
949  // it was originally invoked.  Therefore we change to the original
950  // working directory first.
951  const char* const original_dir =
952      UnitTest::GetInstance()->original_working_dir();
953  // We can safely call chdir() as it's a direct system call.
954  if (chdir(original_dir) != 0) {
955    DeathTestAbort(std::string("chdir(\"") + original_dir + "\") failed: " +
956                   GetLastErrnoDescription());
957    return EXIT_FAILURE;
958  }
959
960  // We can safely call execve() as it's a direct system call.  We
961  // cannot use execvp() as it's a libc function and thus potentially
962  // unsafe.  Since execve() doesn't search the PATH, the user must
963  // invoke the test program via a valid path that contains at least
964  // one path separator.
965  execve(args->argv[0], args->argv, GetEnviron());
966  DeathTestAbort(std::string("execve(") + args->argv[0] + ", ...) in " +
967                 original_dir + " failed: " +
968                 GetLastErrnoDescription());
969  return EXIT_FAILURE;
970}
971#  endif  // !GTEST_OS_QNX
972
973// Two utility routines that together determine the direction the stack
974// grows.
975// This could be accomplished more elegantly by a single recursive
976// function, but we want to guard against the unlikely possibility of
977// a smart compiler optimizing the recursion away.
978//
979// GTEST_NO_INLINE_ is required to prevent GCC 4.6 from inlining
980// StackLowerThanAddress into StackGrowsDown, which then doesn't give
981// correct answer.
982void StackLowerThanAddress(const void* ptr, bool* result) GTEST_NO_INLINE_;
983void StackLowerThanAddress(const void* ptr, bool* result) {
984  int dummy;
985  *result = (&dummy < ptr);
986}
987
988bool StackGrowsDown() {
989  int dummy;
990  bool result;
991  StackLowerThanAddress(&dummy, &result);
992  return result;
993}
994
995// Spawns a child process with the same executable as the current process in
996// a thread-safe manner and instructs it to run the death test.  The
997// implementation uses fork(2) + exec.  On systems where clone(2) is
998// available, it is used instead, being slightly more thread-safe.  On QNX,
999// fork supports only single-threaded environments, so this function uses
1000// spawn(2) there instead.  The function dies with an error message if
1001// anything goes wrong.
1002static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
1003  ExecDeathTestArgs args = { argv, close_fd };
1004  pid_t child_pid = -1;
1005
1006#  if GTEST_OS_QNX
1007  // Obtains the current directory and sets it to be closed in the child
1008  // process.
1009  const int cwd_fd = open(".", O_RDONLY);
1010  GTEST_DEATH_TEST_CHECK_(cwd_fd != -1);
1011  GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(cwd_fd, F_SETFD, FD_CLOEXEC));
1012  // We need to execute the test program in the same environment where
1013  // it was originally invoked.  Therefore we change to the original
1014  // working directory first.
1015  const char* const original_dir =
1016      UnitTest::GetInstance()->original_working_dir();
1017  // We can safely call chdir() as it's a direct system call.
1018  if (chdir(original_dir) != 0) {
1019    DeathTestAbort(std::string("chdir(\"") + original_dir + "\") failed: " +
1020                   GetLastErrnoDescription());
1021    return EXIT_FAILURE;
1022  }
1023
1024  int fd_flags;
1025  // Set close_fd to be closed after spawn.
1026  GTEST_DEATH_TEST_CHECK_SYSCALL_(fd_flags = fcntl(close_fd, F_GETFD));
1027  GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(close_fd, F_SETFD,
1028                                        fd_flags | FD_CLOEXEC));
1029  struct inheritance inherit = {0};
1030  // spawn is a system call.
1031  child_pid = spawn(args.argv[0], 0, NULL, &inherit, args.argv, GetEnviron());
1032  // Restores the current working directory.
1033  GTEST_DEATH_TEST_CHECK_(fchdir(cwd_fd) != -1);
1034  GTEST_DEATH_TEST_CHECK_SYSCALL_(close(cwd_fd));
1035
1036#  else   // GTEST_OS_QNX
1037#   if GTEST_OS_LINUX
1038  // When a SIGPROF signal is received while fork() or clone() are executing,
1039  // the process may hang. To avoid this, we ignore SIGPROF here and re-enable
1040  // it after the call to fork()/clone() is complete.
1041  struct sigaction saved_sigprof_action;
1042  struct sigaction ignore_sigprof_action;
1043  memset(&ignore_sigprof_action, 0, sizeof(ignore_sigprof_action));
1044  sigemptyset(&ignore_sigprof_action.sa_mask);
1045  ignore_sigprof_action.sa_handler = SIG_IGN;
1046  GTEST_DEATH_TEST_CHECK_SYSCALL_(sigaction(
1047      SIGPROF, &ignore_sigprof_action, &saved_sigprof_action));
1048#   endif  // GTEST_OS_LINUX
1049
1050#   if GTEST_HAS_CLONE
1051  const bool use_fork = GTEST_FLAG(death_test_use_fork);
1052
1053  if (!use_fork) {
1054    static const bool stack_grows_down = StackGrowsDown();
1055    const size_t stack_size = getpagesize();
1056    // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
1057    void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
1058                             MAP_ANON | MAP_PRIVATE, -1, 0);
1059    GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
1060
1061    // Maximum stack alignment in bytes:  For a downward-growing stack, this
1062    // amount is subtracted from size of the stack space to get an address
1063    // that is within the stack space and is aligned on all systems we care
1064    // about.  As far as I know there is no ABI with stack alignment greater
1065    // than 64.  We assume stack and stack_size already have alignment of
1066    // kMaxStackAlignment.
1067    const size_t kMaxStackAlignment = 64;
1068    void* const stack_top =
1069        static_cast<char*>(stack) +
1070            (stack_grows_down ? stack_size - kMaxStackAlignment : 0);
1071    GTEST_DEATH_TEST_CHECK_(stack_size > kMaxStackAlignment &&
1072        reinterpret_cast<intptr_t>(stack_top) % kMaxStackAlignment == 0);
1073
1074    child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);
1075
1076    GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
1077  }
1078#   else
1079  const bool use_fork = true;
1080#   endif  // GTEST_HAS_CLONE
1081
1082  if (use_fork && (child_pid = fork()) == 0) {
1083      ExecDeathTestChildMain(&args);
1084      _exit(0);
1085  }
1086#  endif  // GTEST_OS_QNX
1087#  if GTEST_OS_LINUX
1088  GTEST_DEATH_TEST_CHECK_SYSCALL_(
1089      sigaction(SIGPROF, &saved_sigprof_action, NULL));
1090#  endif  // GTEST_OS_LINUX
1091
1092  GTEST_DEATH_TEST_CHECK_(child_pid != -1);
1093  return child_pid;
1094}
1095
1096// The AssumeRole process for a fork-and-exec death test.  It re-executes the
1097// main program from the beginning, setting the --gtest_filter
1098// and --gtest_internal_run_death_test flags to cause only the current
1099// death test to be re-run.
1100DeathTest::TestRole ExecDeathTest::AssumeRole() {
1101  const UnitTestImpl* const impl = GetUnitTestImpl();
1102  const InternalRunDeathTestFlag* const flag =
1103      impl->internal_run_death_test_flag();
1104  const TestInfo* const info = impl->current_test_info();
1105  const int death_test_index = info->result()->death_test_count();
1106
1107  if (flag != NULL) {
1108    set_write_fd(flag->write_fd());
1109    return EXECUTE_TEST;
1110  }
1111
1112  int pipe_fd[2];
1113  GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
1114  // Clear the close-on-exec flag on the write end of the pipe, lest
1115  // it be closed when the child process does an exec:
1116  GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
1117
1118  const std::string filter_flag =
1119      std::string("--") + GTEST_FLAG_PREFIX_ + kFilterFlag + "="
1120      + info->test_case_name() + "." + info->name();
1121  const std::string internal_flag =
1122      std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag + "="
1123      + file_ + "|" + StreamableToString(line_) + "|"
1124      + StreamableToString(death_test_index) + "|"
1125      + StreamableToString(pipe_fd[1]);
1126  Arguments args;
1127  args.AddArguments(GetArgvsForDeathTestChildProcess());
1128  args.AddArgument(filter_flag.c_str());
1129  args.AddArgument(internal_flag.c_str());
1130
1131  DeathTest::set_last_death_test_message("");
1132
1133  CaptureStderr();
1134  // See the comment in NoExecDeathTest::AssumeRole for why the next line
1135  // is necessary.
1136  FlushInfoLog();
1137
1138  const pid_t child_pid = ExecDeathTestSpawnChild(args.Argv(), pipe_fd[0]);
1139  GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
1140  set_child_pid(child_pid);
1141  set_read_fd(pipe_fd[0]);
1142  set_spawned(true);
1143  return OVERSEE_TEST;
1144}
1145
1146# endif  // !GTEST_OS_WINDOWS
1147
1148// Creates a concrete DeathTest-derived class that depends on the
1149// --gtest_death_test_style flag, and sets the pointer pointed to
1150// by the "test" argument to its address.  If the test should be
1151// skipped, sets that pointer to NULL.  Returns true, unless the
1152// flag is set to an invalid value.
1153bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
1154                                     const char* file, int line,
1155                                     DeathTest** test) {
1156  UnitTestImpl* const impl = GetUnitTestImpl();
1157  const InternalRunDeathTestFlag* const flag =
1158      impl->internal_run_death_test_flag();
1159  const int death_test_index = impl->current_test_info()
1160      ->increment_death_test_count();
1161
1162  if (flag != NULL) {
1163    if (death_test_index > flag->index()) {
1164      DeathTest::set_last_death_test_message(
1165          "Death test count (" + StreamableToString(death_test_index)
1166          + ") somehow exceeded expected maximum ("
1167          + StreamableToString(flag->index()) + ")");
1168      return false;
1169    }
1170
1171    if (!(flag->file() == file && flag->line() == line &&
1172          flag->index() == death_test_index)) {
1173      *test = NULL;
1174      return true;
1175    }
1176  }
1177
1178# if GTEST_OS_WINDOWS
1179
1180  if (GTEST_FLAG(death_test_style) == "threadsafe" ||
1181      GTEST_FLAG(death_test_style) == "fast") {
1182    *test = new WindowsDeathTest(statement, regex, file, line);
1183  }
1184
1185# else
1186
1187  if (GTEST_FLAG(death_test_style) == "threadsafe") {
1188    *test = new ExecDeathTest(statement, regex, file, line);
1189  } else if (GTEST_FLAG(death_test_style) == "fast") {
1190    *test = new NoExecDeathTest(statement, regex);
1191  }
1192
1193# endif  // GTEST_OS_WINDOWS
1194
1195  else {  // NOLINT - this is more readable than unbalanced brackets inside #if.
1196    DeathTest::set_last_death_test_message(
1197        "Unknown death test style \"" + GTEST_FLAG(death_test_style)
1198        + "\" encountered");
1199    return false;
1200  }
1201
1202  return true;
1203}
1204
1205// Splits a given string on a given delimiter, populating a given
1206// vector with the fields.  GTEST_HAS_DEATH_TEST implies that we have
1207// ::std::string, so we can use it here.
1208static void SplitString(const ::std::string& str, char delimiter,
1209                        ::std::vector< ::std::string>* dest) {
1210  ::std::vector< ::std::string> parsed;
1211  ::std::string::size_type pos = 0;
1212  while (::testing::internal::AlwaysTrue()) {
1213    const ::std::string::size_type colon = str.find(delimiter, pos);
1214    if (colon == ::std::string::npos) {
1215      parsed.push_back(str.substr(pos));
1216      break;
1217    } else {
1218      parsed.push_back(str.substr(pos, colon - pos));
1219      pos = colon + 1;
1220    }
1221  }
1222  dest->swap(parsed);
1223}
1224
1225# if GTEST_OS_WINDOWS
1226// Recreates the pipe and event handles from the provided parameters,
1227// signals the event, and returns a file descriptor wrapped around the pipe
1228// handle. This function is called in the child process only.
1229int GetStatusFileDescriptor(unsigned int parent_process_id,
1230                            size_t write_handle_as_size_t,
1231                            size_t event_handle_as_size_t) {
1232  AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
1233                                                   FALSE,  // Non-inheritable.
1234                                                   parent_process_id));
1235  if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
1236    DeathTestAbort("Unable to open parent process " +
1237                   StreamableToString(parent_process_id));
1238  }
1239
1240  // TODO(vladl@google.com): Replace the following check with a
1241  // compile-time assertion when available.
1242  GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));
1243
1244  const HANDLE write_handle =
1245      reinterpret_cast<HANDLE>(write_handle_as_size_t);
1246  HANDLE dup_write_handle;
1247
1248  // The newly initialized handle is accessible only in in the parent
1249  // process. To obtain one accessible within the child, we need to use
1250  // DuplicateHandle.
1251  if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
1252                         ::GetCurrentProcess(), &dup_write_handle,
1253                         0x0,    // Requested privileges ignored since
1254                                 // DUPLICATE_SAME_ACCESS is used.
1255                         FALSE,  // Request non-inheritable handler.
1256                         DUPLICATE_SAME_ACCESS)) {
1257    DeathTestAbort("Unable to duplicate the pipe handle " +
1258                   StreamableToString(write_handle_as_size_t) +
1259                   " from the parent process " +
1260                   StreamableToString(parent_process_id));
1261  }
1262
1263  const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
1264  HANDLE dup_event_handle;
1265
1266  if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
1267                         ::GetCurrentProcess(), &dup_event_handle,
1268                         0x0,
1269                         FALSE,
1270                         DUPLICATE_SAME_ACCESS)) {
1271    DeathTestAbort("Unable to duplicate the event handle " +
1272                   StreamableToString(event_handle_as_size_t) +
1273                   " from the parent process " +
1274                   StreamableToString(parent_process_id));
1275  }
1276
1277  const int write_fd =
1278      ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
1279  if (write_fd == -1) {
1280    DeathTestAbort("Unable to convert pipe handle " +
1281                   StreamableToString(write_handle_as_size_t) +
1282                   " to a file descriptor");
1283  }
1284
1285  // Signals the parent that the write end of the pipe has been acquired
1286  // so the parent can release its own write end.
1287  ::SetEvent(dup_event_handle);
1288
1289  return write_fd;
1290}
1291# endif  // GTEST_OS_WINDOWS
1292
1293// Returns a newly created InternalRunDeathTestFlag object with fields
1294// initialized from the GTEST_FLAG(internal_run_death_test) flag if
1295// the flag is specified; otherwise returns NULL.
1296InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
1297  if (GTEST_FLAG(internal_run_death_test) == "") return NULL;
1298
1299  // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
1300  // can use it here.
1301  int line = -1;
1302  int index = -1;
1303  ::std::vector< ::std::string> fields;
1304  SplitString(GTEST_FLAG(internal_run_death_test).c_str(), '|', &fields);
1305  int write_fd = -1;
1306
1307# if GTEST_OS_WINDOWS
1308
1309  unsigned int parent_process_id = 0;
1310  size_t write_handle_as_size_t = 0;
1311  size_t event_handle_as_size_t = 0;
1312
1313  if (fields.size() != 6
1314      || !ParseNaturalNumber(fields[1], &line)
1315      || !ParseNaturalNumber(fields[2], &index)
1316      || !ParseNaturalNumber(fields[3], &parent_process_id)
1317      || !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
1318      || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
1319    DeathTestAbort("Bad --gtest_internal_run_death_test flag: " +
1320                   GTEST_FLAG(internal_run_death_test));
1321  }
1322  write_fd = GetStatusFileDescriptor(parent_process_id,
1323                                     write_handle_as_size_t,
1324                                     event_handle_as_size_t);
1325# else
1326
1327  if (fields.size() != 4
1328      || !ParseNaturalNumber(fields[1], &line)
1329      || !ParseNaturalNumber(fields[2], &index)
1330      || !ParseNaturalNumber(fields[3], &write_fd)) {
1331    DeathTestAbort("Bad --gtest_internal_run_death_test flag: "
1332        + GTEST_FLAG(internal_run_death_test));
1333  }
1334
1335# endif  // GTEST_OS_WINDOWS
1336
1337  return new InternalRunDeathTestFlag(fields[0], line, index, write_fd);
1338}
1339
1340}  // namespace internal
1341
1342#endif  // GTEST_HAS_DEATH_TEST
1343
1344}  // namespace testing
1345