1// Copyright 2005, Google Inc.
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28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30//
31// This file implements death tests.
32
33#include "gtest/gtest-death-test.h"
34
35#include <functional>
36#include <utility>
37
38#include "gtest/internal/gtest-port.h"
39#include "gtest/internal/custom/gtest.h"
40
41#if GTEST_HAS_DEATH_TEST
42
43# if GTEST_OS_MAC
44# include <crt_externs.h>
45# endif // GTEST_OS_MAC
46
47# include <errno.h>
48# include <fcntl.h>
49# include <limits.h>
50
51# if GTEST_OS_LINUX
52# include <signal.h>
53# endif // GTEST_OS_LINUX
54
55# include <stdarg.h>
56
57# if GTEST_OS_WINDOWS
58# include <windows.h>
59# else
60# include <sys/mman.h>
61# include <sys/wait.h>
62# endif // GTEST_OS_WINDOWS
63
64# if GTEST_OS_QNX
65# include <spawn.h>
66# endif // GTEST_OS_QNX
67
68# if GTEST_OS_FUCHSIA
69# include <lib/fdio/fd.h>
70# include <lib/fdio/io.h>
71# include <lib/fdio/spawn.h>
72# include <lib/zx/channel.h>
73# include <lib/zx/port.h>
74# include <lib/zx/process.h>
75# include <lib/zx/socket.h>
76# include <zircon/processargs.h>
77# include <zircon/syscalls.h>
78# include <zircon/syscalls/policy.h>
79# include <zircon/syscalls/port.h>
80# endif // GTEST_OS_FUCHSIA
81
82#endif // GTEST_HAS_DEATH_TEST
83
84#include "gtest/gtest-message.h"
85#include "gtest/internal/gtest-string.h"
86#include "src/gtest-internal-inl.h"
87
88namespace testing {
89
90// Constants.
91
92// The default death test style.
93//
94// This is defined in internal/gtest-port.h as "fast", but can be overridden by
95// a definition in internal/custom/gtest-port.h. The recommended value, which is
96// used internally at Google, is "threadsafe".
97static const char kDefaultDeathTestStyle[] = GTEST_DEFAULT_DEATH_TEST_STYLE;
98
99} // namespace testing
100
101GTEST_DEFINE_string_(
102 death_test_style,
103 testing::internal::StringFromGTestEnv("death_test_style",
104 testing::kDefaultDeathTestStyle),
105 "Indicates how to run a death test in a forked child process: "
106 "\"threadsafe\" (child process re-executes the test binary "
107 "from the beginning, running only the specific death test) or "
108 "\"fast\" (child process runs the death test immediately "
109 "after forking).");
110
111GTEST_DEFINE_bool_(
112 death_test_use_fork,
113 testing::internal::BoolFromGTestEnv("death_test_use_fork", false),
114 "Instructs to use fork()/_exit() instead of clone() in death tests. "
115 "Ignored and always uses fork() on POSIX systems where clone() is not "
116 "implemented. Useful when running under valgrind or similar tools if "
117 "those do not support clone(). Valgrind 3.3.1 will just fail if "
118 "it sees an unsupported combination of clone() flags. "
119 "It is not recommended to use this flag w/o valgrind though it will "
120 "work in 99% of the cases. Once valgrind is fixed, this flag will "
121 "most likely be removed.");
122
123GTEST_DEFINE_string_(
124 internal_run_death_test, "",
125 "Indicates the file, line number, temporal index of "
126 "the single death test to run, and a file descriptor to "
127 "which a success code may be sent, all separated by "
128 "the '|' characters. This flag is specified if and only if the "
129 "current process is a sub-process launched for running a thread-safe "
130 "death test. FOR INTERNAL USE ONLY.");
131
132namespace testing {
133
134#if GTEST_HAS_DEATH_TEST
135
136namespace internal {
137
138// Valid only for fast death tests. Indicates the code is running in the
139// child process of a fast style death test.
140# if !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA
141static bool g_in_fast_death_test_child = false;
142# endif
143
144// Returns a Boolean value indicating whether the caller is currently
145// executing in the context of the death test child process. Tools such as
146// Valgrind heap checkers may need this to modify their behavior in death
147// tests. IMPORTANT: This is an internal utility. Using it may break the
148// implementation of death tests. User code MUST NOT use it.
149bool InDeathTestChild() {
150# if GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
151
152 // On Windows and Fuchsia, death tests are thread-safe regardless of the value
153 // of the death_test_style flag.
154 return !GTEST_FLAG_GET(internal_run_death_test).empty();
155
156# else
157
158 if (GTEST_FLAG_GET(death_test_style) == "threadsafe")
159 return !GTEST_FLAG_GET(internal_run_death_test).empty();
160 else
161 return g_in_fast_death_test_child;
162#endif
163}
164
165} // namespace internal
166
167// ExitedWithCode constructor.
168ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
169}
170
171// ExitedWithCode function-call operator.
172bool ExitedWithCode::operator()(int exit_status) const {
173# if GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
174
175 return exit_status == exit_code_;
176
177# else
178
179 return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;
180
181# endif // GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
182}
183
184# if !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA
185// KilledBySignal constructor.
186KilledBySignal::KilledBySignal(int signum) : signum_(signum) {
187}
188
189// KilledBySignal function-call operator.
190bool KilledBySignal::operator()(int exit_status) const {
191# if defined(GTEST_KILLED_BY_SIGNAL_OVERRIDE_)
192 {
193 bool result;
194 if (GTEST_KILLED_BY_SIGNAL_OVERRIDE_(signum_, exit_status, &result)) {
195 return result;
196 }
197 }
198# endif // defined(GTEST_KILLED_BY_SIGNAL_OVERRIDE_)
199 return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;
200}
201# endif // !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA
202
203namespace internal {
204
205// Utilities needed for death tests.
206
207// Generates a textual description of a given exit code, in the format
208// specified by wait(2).
209static std::string ExitSummary(int exit_code) {
210 Message m;
211
212# if GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
213
214 m << "Exited with exit status " << exit_code;
215
216# else
217
218 if (WIFEXITED(exit_code)) {
219 m << "Exited with exit status " << WEXITSTATUS(exit_code);
220 } else if (WIFSIGNALED(exit_code)) {
221 m << "Terminated by signal " << WTERMSIG(exit_code);
222 }
223# ifdef WCOREDUMP
224 if (WCOREDUMP(exit_code)) {
225 m << " (core dumped)";
226 }
227# endif
228# endif // GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
229
230 return m.GetString();
231}
232
233// Returns true if exit_status describes a process that was terminated
234// by a signal, or exited normally with a nonzero exit code.
235bool ExitedUnsuccessfully(int exit_status) {
236 return !ExitedWithCode(0)(exit_status);
237}
238
239# if !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA
240// Generates a textual failure message when a death test finds more than
241// one thread running, or cannot determine the number of threads, prior
242// to executing the given statement. It is the responsibility of the
243// caller not to pass a thread_count of 1.
244static std::string DeathTestThreadWarning(size_t thread_count) {
245 Message msg;
246 msg << "Death tests use fork(), which is unsafe particularly"
247 << " in a threaded context. For this test, " << GTEST_NAME_ << " ";
248 if (thread_count == 0) {
249 msg << "couldn't detect the number of threads.";
250 } else {
251 msg << "detected " << thread_count << " threads.";
252 }
253 msg << " See "
254 "https://github.com/google/googletest/blob/master/docs/"
255 "advanced.md#death-tests-and-threads"
256 << " for more explanation and suggested solutions, especially if"
257 << " this is the last message you see before your test times out.";
258 return msg.GetString();
259}
260# endif // !GTEST_OS_WINDOWS && !GTEST_OS_FUCHSIA
261
262// Flag characters for reporting a death test that did not die.
263static const char kDeathTestLived = 'L';
264static const char kDeathTestReturned = 'R';
265static const char kDeathTestThrew = 'T';
266static const char kDeathTestInternalError = 'I';
267
268#if GTEST_OS_FUCHSIA
269
270// File descriptor used for the pipe in the child process.
271static const int kFuchsiaReadPipeFd = 3;
272
273#endif
274
275// An enumeration describing all of the possible ways that a death test can
276// conclude. DIED means that the process died while executing the test
277// code; LIVED means that process lived beyond the end of the test code;
278// RETURNED means that the test statement attempted to execute a return
279// statement, which is not allowed; THREW means that the test statement
280// returned control by throwing an exception. IN_PROGRESS means the test
281// has not yet concluded.
282enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED, THREW };
283
284// Routine for aborting the program which is safe to call from an
285// exec-style death test child process, in which case the error
286// message is propagated back to the parent process. Otherwise, the
287// message is simply printed to stderr. In either case, the program
288// then exits with status 1.
289static void DeathTestAbort(const std::string& message) {
290 // On a POSIX system, this function may be called from a threadsafe-style
291 // death test child process, which operates on a very small stack. Use
292 // the heap for any additional non-minuscule memory requirements.
293 const InternalRunDeathTestFlag* const flag =
294 GetUnitTestImpl()->internal_run_death_test_flag();
295 if (flag != nullptr) {
296 FILE* parent = posix::FDOpen(fd: flag->write_fd(), mode: "w");
297 fputc(c: kDeathTestInternalError, stream: parent);
298 fprintf(stream: parent, format: "%s", message.c_str());
299 fflush(stream: parent);
300 _exit(status: 1);
301 } else {
302 fprintf(stderr, format: "%s", message.c_str());
303 fflush(stderr);
304 posix::Abort();
305 }
306}
307
308// A replacement for CHECK that calls DeathTestAbort if the assertion
309// fails.
310# define GTEST_DEATH_TEST_CHECK_(expression) \
311 do { \
312 if (!::testing::internal::IsTrue(expression)) { \
313 DeathTestAbort( \
314 ::std::string("CHECK failed: File ") + __FILE__ + ", line " \
315 + ::testing::internal::StreamableToString(__LINE__) + ": " \
316 + #expression); \
317 } \
318 } while (::testing::internal::AlwaysFalse())
319
320// This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
321// evaluating any system call that fulfills two conditions: it must return
322// -1 on failure, and set errno to EINTR when it is interrupted and
323// should be tried again. The macro expands to a loop that repeatedly
324// evaluates the expression as long as it evaluates to -1 and sets
325// errno to EINTR. If the expression evaluates to -1 but errno is
326// something other than EINTR, DeathTestAbort is called.
327# define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \
328 do { \
329 int gtest_retval; \
330 do { \
331 gtest_retval = (expression); \
332 } while (gtest_retval == -1 && errno == EINTR); \
333 if (gtest_retval == -1) { \
334 DeathTestAbort( \
335 ::std::string("CHECK failed: File ") + __FILE__ + ", line " \
336 + ::testing::internal::StreamableToString(__LINE__) + ": " \
337 + #expression + " != -1"); \
338 } \
339 } while (::testing::internal::AlwaysFalse())
340
341// Returns the message describing the last system error in errno.
342std::string GetLastErrnoDescription() {
343 return errno == 0 ? "" : posix::StrError(errno);
344}
345
346// This is called from a death test parent process to read a failure
347// message from the death test child process and log it with the FATAL
348// severity. On Windows, the message is read from a pipe handle. On other
349// platforms, it is read from a file descriptor.
350static void FailFromInternalError(int fd) {
351 Message error;
352 char buffer[256];
353 int num_read;
354
355 do {
356 while ((num_read = posix::Read(fd, buf: buffer, count: 255)) > 0) {
357 buffer[num_read] = '\0';
358 error << buffer;
359 }
360 } while (num_read == -1 && errno == EINTR);
361
362 if (num_read == 0) {
363 GTEST_LOG_(FATAL) << error.GetString();
364 } else {
365 const int last_error = errno;
366 GTEST_LOG_(FATAL) << "Error while reading death test internal: "
367 << GetLastErrnoDescription() << " [" << last_error << "]";
368 }
369}
370
371// Death test constructor. Increments the running death test count
372// for the current test.
373DeathTest::DeathTest() {
374 TestInfo* const info = GetUnitTestImpl()->current_test_info();
375 if (info == nullptr) {
376 DeathTestAbort(message: "Cannot run a death test outside of a TEST or "
377 "TEST_F construct");
378 }
379}
380
381// Creates and returns a death test by dispatching to the current
382// death test factory.
383bool DeathTest::Create(const char* statement,
384 Matcher<const std::string&> matcher, const char* file,
385 int line, DeathTest** test) {
386 return GetUnitTestImpl()->death_test_factory()->Create(
387 statement, matcher: std::move(matcher), file, line, test);
388}
389
390const char* DeathTest::LastMessage() {
391 return last_death_test_message_.c_str();
392}
393
394void DeathTest::set_last_death_test_message(const std::string& message) {
395 last_death_test_message_ = message;
396}
397
398std::string DeathTest::last_death_test_message_;
399
400// Provides cross platform implementation for some death functionality.
401class DeathTestImpl : public DeathTest {
402 protected:
403 DeathTestImpl(const char* a_statement, Matcher<const std::string&> matcher)
404 : statement_(a_statement),
405 matcher_(std::move(matcher)),
406 spawned_(false),
407 status_(-1),
408 outcome_(IN_PROGRESS),
409 read_fd_(-1),
410 write_fd_(-1) {}
411
412 // read_fd_ is expected to be closed and cleared by a derived class.
413 ~DeathTestImpl() override { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }
414
415 void Abort(AbortReason reason) override;
416 bool Passed(bool status_ok) override;
417
418 const char* statement() const { return statement_; }
419 bool spawned() const { return spawned_; }
420 void set_spawned(bool is_spawned) { spawned_ = is_spawned; }
421 int status() const { return status_; }
422 void set_status(int a_status) { status_ = a_status; }
423 DeathTestOutcome outcome() const { return outcome_; }
424 void set_outcome(DeathTestOutcome an_outcome) { outcome_ = an_outcome; }
425 int read_fd() const { return read_fd_; }
426 void set_read_fd(int fd) { read_fd_ = fd; }
427 int write_fd() const { return write_fd_; }
428 void set_write_fd(int fd) { write_fd_ = fd; }
429
430 // Called in the parent process only. Reads the result code of the death
431 // test child process via a pipe, interprets it to set the outcome_
432 // member, and closes read_fd_. Outputs diagnostics and terminates in
433 // case of unexpected codes.
434 void ReadAndInterpretStatusByte();
435
436 // Returns stderr output from the child process.
437 virtual std::string GetErrorLogs();
438
439 private:
440 // The textual content of the code this object is testing. This class
441 // doesn't own this string and should not attempt to delete it.
442 const char* const statement_;
443 // A matcher that's expected to match the stderr output by the child process.
444 Matcher<const std::string&> matcher_;
445 // True if the death test child process has been successfully spawned.
446 bool spawned_;
447 // The exit status of the child process.
448 int status_;
449 // How the death test concluded.
450 DeathTestOutcome outcome_;
451 // Descriptor to the read end of the pipe to the child process. It is
452 // always -1 in the child process. The child keeps its write end of the
453 // pipe in write_fd_.
454 int read_fd_;
455 // Descriptor to the child's write end of the pipe to the parent process.
456 // It is always -1 in the parent process. The parent keeps its end of the
457 // pipe in read_fd_.
458 int write_fd_;
459};
460
461// Called in the parent process only. Reads the result code of the death
462// test child process via a pipe, interprets it to set the outcome_
463// member, and closes read_fd_. Outputs diagnostics and terminates in
464// case of unexpected codes.
465void DeathTestImpl::ReadAndInterpretStatusByte() {
466 char flag;
467 int bytes_read;
468
469 // The read() here blocks until data is available (signifying the
470 // failure of the death test) or until the pipe is closed (signifying
471 // its success), so it's okay to call this in the parent before
472 // the child process has exited.
473 do {
474 bytes_read = posix::Read(fd: read_fd(), buf: &flag, count: 1);
475 } while (bytes_read == -1 && errno == EINTR);
476
477 if (bytes_read == 0) {
478 set_outcome(DIED);
479 } else if (bytes_read == 1) {
480 switch (flag) {
481 case kDeathTestReturned:
482 set_outcome(RETURNED);
483 break;
484 case kDeathTestThrew:
485 set_outcome(THREW);
486 break;
487 case kDeathTestLived:
488 set_outcome(LIVED);
489 break;
490 case kDeathTestInternalError:
491 FailFromInternalError(fd: read_fd()); // Does not return.
492 break;
493 default:
494 GTEST_LOG_(FATAL) << "Death test child process reported "
495 << "unexpected status byte ("
496 << static_cast<unsigned int>(flag) << ")";
497 }
498 } else {
499 GTEST_LOG_(FATAL) << "Read from death test child process failed: "
500 << GetLastErrnoDescription();
501 }
502 GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));
503 set_read_fd(-1);
504}
505
506std::string DeathTestImpl::GetErrorLogs() {
507 return GetCapturedStderr();
508}
509
510// Signals that the death test code which should have exited, didn't.
511// Should be called only in a death test child process.
512// Writes a status byte to the child's status file descriptor, then
513// calls _exit(1).
514void DeathTestImpl::Abort(AbortReason reason) {
515 // The parent process considers the death test to be a failure if
516 // it finds any data in our pipe. So, here we write a single flag byte
517 // to the pipe, then exit.
518 const char status_ch =
519 reason == TEST_DID_NOT_DIE ? kDeathTestLived :
520 reason == TEST_THREW_EXCEPTION ? kDeathTestThrew : kDeathTestReturned;
521
522 GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));
523 // We are leaking the descriptor here because on some platforms (i.e.,
524 // when built as Windows DLL), destructors of global objects will still
525 // run after calling _exit(). On such systems, write_fd_ will be
526 // indirectly closed from the destructor of UnitTestImpl, causing double
527 // close if it is also closed here. On debug configurations, double close
528 // may assert. As there are no in-process buffers to flush here, we are
529 // relying on the OS to close the descriptor after the process terminates
530 // when the destructors are not run.
531 _exit(status: 1); // Exits w/o any normal exit hooks (we were supposed to crash)
532}
533
534// Returns an indented copy of stderr output for a death test.
535// This makes distinguishing death test output lines from regular log lines
536// much easier.
537static ::std::string FormatDeathTestOutput(const ::std::string& output) {
538 ::std::string ret;
539 for (size_t at = 0; ; ) {
540 const size_t line_end = output.find(c: '\n', pos: at);
541 ret += "[ DEATH ] ";
542 if (line_end == ::std::string::npos) {
543 ret += output.substr(pos: at);
544 break;
545 }
546 ret += output.substr(pos: at, n: line_end + 1 - at);
547 at = line_end + 1;
548 }
549 return ret;
550}
551
552// Assesses the success or failure of a death test, using both private
553// members which have previously been set, and one argument:
554//
555// Private data members:
556// outcome: An enumeration describing how the death test
557// concluded: DIED, LIVED, THREW, or RETURNED. The death test
558// fails in the latter three cases.
559// status: The exit status of the child process. On *nix, it is in the
560// in the format specified by wait(2). On Windows, this is the
561// value supplied to the ExitProcess() API or a numeric code
562// of the exception that terminated the program.
563// matcher_: A matcher that's expected to match the stderr output by the child
564// process.
565//
566// Argument:
567// status_ok: true if exit_status is acceptable in the context of
568// this particular death test, which fails if it is false
569//
570// Returns true if and only if all of the above conditions are met. Otherwise,
571// the first failing condition, in the order given above, is the one that is
572// reported. Also sets the last death test message string.
573bool DeathTestImpl::Passed(bool status_ok) {
574 if (!spawned())
575 return false;
576
577 const std::string error_message = GetErrorLogs();
578
579 bool success = false;
580 Message buffer;
581
582 buffer << "Death test: " << statement() << "\n";
583 switch (outcome()) {
584 case LIVED:
585 buffer << " Result: failed to die.\n"
586 << " Error msg:\n" << FormatDeathTestOutput(output: error_message);
587 break;
588 case THREW:
589 buffer << " Result: threw an exception.\n"
590 << " Error msg:\n" << FormatDeathTestOutput(output: error_message);
591 break;
592 case RETURNED:
593 buffer << " Result: illegal return in test statement.\n"
594 << " Error msg:\n" << FormatDeathTestOutput(output: error_message);
595 break;
596 case DIED:
597 if (status_ok) {
598 if (matcher_.Matches(x: error_message)) {
599 success = true;
600 } else {
601 std::ostringstream stream;
602 matcher_.DescribeTo(os: &stream);
603 buffer << " Result: died but not with expected error.\n"
604 << " Expected: " << stream.str() << "\n"
605 << "Actual msg:\n"
606 << FormatDeathTestOutput(output: error_message);
607 }
608 } else {
609 buffer << " Result: died but not with expected exit code:\n"
610 << " " << ExitSummary(exit_code: status()) << "\n"
611 << "Actual msg:\n" << FormatDeathTestOutput(output: error_message);
612 }
613 break;
614 case IN_PROGRESS:
615 default:
616 GTEST_LOG_(FATAL)
617 << "DeathTest::Passed somehow called before conclusion of test";
618 }
619
620 DeathTest::set_last_death_test_message(buffer.GetString());
621 return success;
622}
623
624# if GTEST_OS_WINDOWS
625// WindowsDeathTest implements death tests on Windows. Due to the
626// specifics of starting new processes on Windows, death tests there are
627// always threadsafe, and Google Test considers the
628// --gtest_death_test_style=fast setting to be equivalent to
629// --gtest_death_test_style=threadsafe there.
630//
631// A few implementation notes: Like the Linux version, the Windows
632// implementation uses pipes for child-to-parent communication. But due to
633// the specifics of pipes on Windows, some extra steps are required:
634//
635// 1. The parent creates a communication pipe and stores handles to both
636// ends of it.
637// 2. The parent starts the child and provides it with the information
638// necessary to acquire the handle to the write end of the pipe.
639// 3. The child acquires the write end of the pipe and signals the parent
640// using a Windows event.
641// 4. Now the parent can release the write end of the pipe on its side. If
642// this is done before step 3, the object's reference count goes down to
643// 0 and it is destroyed, preventing the child from acquiring it. The
644// parent now has to release it, or read operations on the read end of
645// the pipe will not return when the child terminates.
646// 5. The parent reads child's output through the pipe (outcome code and
647// any possible error messages) from the pipe, and its stderr and then
648// determines whether to fail the test.
649//
650// Note: to distinguish Win32 API calls from the local method and function
651// calls, the former are explicitly resolved in the global namespace.
652//
653class WindowsDeathTest : public DeathTestImpl {
654 public:
655 WindowsDeathTest(const char* a_statement, Matcher<const std::string&> matcher,
656 const char* file, int line)
657 : DeathTestImpl(a_statement, std::move(matcher)),
658 file_(file),
659 line_(line) {}
660
661 // All of these virtual functions are inherited from DeathTest.
662 virtual int Wait();
663 virtual TestRole AssumeRole();
664
665 private:
666 // The name of the file in which the death test is located.
667 const char* const file_;
668 // The line number on which the death test is located.
669 const int line_;
670 // Handle to the write end of the pipe to the child process.
671 AutoHandle write_handle_;
672 // Child process handle.
673 AutoHandle child_handle_;
674 // Event the child process uses to signal the parent that it has
675 // acquired the handle to the write end of the pipe. After seeing this
676 // event the parent can release its own handles to make sure its
677 // ReadFile() calls return when the child terminates.
678 AutoHandle event_handle_;
679};
680
681// Waits for the child in a death test to exit, returning its exit
682// status, or 0 if no child process exists. As a side effect, sets the
683// outcome data member.
684int WindowsDeathTest::Wait() {
685 if (!spawned())
686 return 0;
687
688 // Wait until the child either signals that it has acquired the write end
689 // of the pipe or it dies.
690 const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() };
691 switch (::WaitForMultipleObjects(2,
692 wait_handles,
693 FALSE, // Waits for any of the handles.
694 INFINITE)) {
695 case WAIT_OBJECT_0:
696 case WAIT_OBJECT_0 + 1:
697 break;
698 default:
699 GTEST_DEATH_TEST_CHECK_(false); // Should not get here.
700 }
701
702 // The child has acquired the write end of the pipe or exited.
703 // We release the handle on our side and continue.
704 write_handle_.Reset();
705 event_handle_.Reset();
706
707 ReadAndInterpretStatusByte();
708
709 // Waits for the child process to exit if it haven't already. This
710 // returns immediately if the child has already exited, regardless of
711 // whether previous calls to WaitForMultipleObjects synchronized on this
712 // handle or not.
713 GTEST_DEATH_TEST_CHECK_(
714 WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(),
715 INFINITE));
716 DWORD status_code;
717 GTEST_DEATH_TEST_CHECK_(
718 ::GetExitCodeProcess(child_handle_.Get(), &status_code) != FALSE);
719 child_handle_.Reset();
720 set_status(static_cast<int>(status_code));
721 return status();
722}
723
724// The AssumeRole process for a Windows death test. It creates a child
725// process with the same executable as the current process to run the
726// death test. The child process is given the --gtest_filter and
727// --gtest_internal_run_death_test flags such that it knows to run the
728// current death test only.
729DeathTest::TestRole WindowsDeathTest::AssumeRole() {
730 const UnitTestImpl* const impl = GetUnitTestImpl();
731 const InternalRunDeathTestFlag* const flag =
732 impl->internal_run_death_test_flag();
733 const TestInfo* const info = impl->current_test_info();
734 const int death_test_index = info->result()->death_test_count();
735
736 if (flag != nullptr) {
737 // ParseInternalRunDeathTestFlag() has performed all the necessary
738 // processing.
739 set_write_fd(flag->write_fd());
740 return EXECUTE_TEST;
741 }
742
743 // WindowsDeathTest uses an anonymous pipe to communicate results of
744 // a death test.
745 SECURITY_ATTRIBUTES handles_are_inheritable = {sizeof(SECURITY_ATTRIBUTES),
746 nullptr, TRUE};
747 HANDLE read_handle, write_handle;
748 GTEST_DEATH_TEST_CHECK_(
749 ::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable,
750 0) // Default buffer size.
751 != FALSE);
752 set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle),
753 O_RDONLY));
754 write_handle_.Reset(write_handle);
755 event_handle_.Reset(::CreateEvent(
756 &handles_are_inheritable,
757 TRUE, // The event will automatically reset to non-signaled state.
758 FALSE, // The initial state is non-signalled.
759 nullptr)); // The even is unnamed.
760 GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != nullptr);
761 const std::string filter_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
762 "filter=" + info->test_suite_name() + "." +
763 info->name();
764 const std::string internal_flag =
765 std::string("--") + GTEST_FLAG_PREFIX_ +
766 "internal_run_death_test=" + file_ + "|" + StreamableToString(line_) +
767 "|" + StreamableToString(death_test_index) + "|" +
768 StreamableToString(static_cast<unsigned int>(::GetCurrentProcessId())) +
769 // size_t has the same width as pointers on both 32-bit and 64-bit
770 // Windows platforms.
771 // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
772 "|" + StreamableToString(reinterpret_cast<size_t>(write_handle)) + "|" +
773 StreamableToString(reinterpret_cast<size_t>(event_handle_.Get()));
774
775 char executable_path[_MAX_PATH + 1]; // NOLINT
776 GTEST_DEATH_TEST_CHECK_(_MAX_PATH + 1 != ::GetModuleFileNameA(nullptr,
777 executable_path,
778 _MAX_PATH));
779
780 std::string command_line =
781 std::string(::GetCommandLineA()) + " " + filter_flag + " \"" +
782 internal_flag + "\"";
783
784 DeathTest::set_last_death_test_message("");
785
786 CaptureStderr();
787 // Flush the log buffers since the log streams are shared with the child.
788 FlushInfoLog();
789
790 // The child process will share the standard handles with the parent.
791 STARTUPINFOA startup_info;
792 memset(&startup_info, 0, sizeof(STARTUPINFO));
793 startup_info.dwFlags = STARTF_USESTDHANDLES;
794 startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
795 startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
796 startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);
797
798 PROCESS_INFORMATION process_info;
799 GTEST_DEATH_TEST_CHECK_(
800 ::CreateProcessA(
801 executable_path, const_cast<char*>(command_line.c_str()),
802 nullptr, // Returned process handle is not inheritable.
803 nullptr, // Returned thread handle is not inheritable.
804 TRUE, // Child inherits all inheritable handles (for write_handle_).
805 0x0, // Default creation flags.
806 nullptr, // Inherit the parent's environment.
807 UnitTest::GetInstance()->original_working_dir(), &startup_info,
808 &process_info) != FALSE);
809 child_handle_.Reset(process_info.hProcess);
810 ::CloseHandle(process_info.hThread);
811 set_spawned(true);
812 return OVERSEE_TEST;
813}
814
815# elif GTEST_OS_FUCHSIA
816
817class FuchsiaDeathTest : public DeathTestImpl {
818 public:
819 FuchsiaDeathTest(const char* a_statement, Matcher<const std::string&> matcher,
820 const char* file, int line)
821 : DeathTestImpl(a_statement, std::move(matcher)),
822 file_(file),
823 line_(line) {}
824
825 // All of these virtual functions are inherited from DeathTest.
826 int Wait() override;
827 TestRole AssumeRole() override;
828 std::string GetErrorLogs() override;
829
830 private:
831 // The name of the file in which the death test is located.
832 const char* const file_;
833 // The line number on which the death test is located.
834 const int line_;
835 // The stderr data captured by the child process.
836 std::string captured_stderr_;
837
838 zx::process child_process_;
839 zx::channel exception_channel_;
840 zx::socket stderr_socket_;
841};
842
843// Utility class for accumulating command-line arguments.
844class Arguments {
845 public:
846 Arguments() { args_.push_back(nullptr); }
847
848 ~Arguments() {
849 for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
850 ++i) {
851 free(*i);
852 }
853 }
854 void AddArgument(const char* argument) {
855 args_.insert(args_.end() - 1, posix::StrDup(argument));
856 }
857
858 template <typename Str>
859 void AddArguments(const ::std::vector<Str>& arguments) {
860 for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
861 i != arguments.end();
862 ++i) {
863 args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));
864 }
865 }
866 char* const* Argv() {
867 return &args_[0];
868 }
869
870 int size() {
871 return static_cast<int>(args_.size()) - 1;
872 }
873
874 private:
875 std::vector<char*> args_;
876};
877
878// Waits for the child in a death test to exit, returning its exit
879// status, or 0 if no child process exists. As a side effect, sets the
880// outcome data member.
881int FuchsiaDeathTest::Wait() {
882 const int kProcessKey = 0;
883 const int kSocketKey = 1;
884 const int kExceptionKey = 2;
885
886 if (!spawned())
887 return 0;
888
889 // Create a port to wait for socket/task/exception events.
890 zx_status_t status_zx;
891 zx::port port;
892 status_zx = zx::port::create(0, &port);
893 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
894
895 // Register to wait for the child process to terminate.
896 status_zx = child_process_.wait_async(
897 port, kProcessKey, ZX_PROCESS_TERMINATED, 0);
898 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
899
900 // Register to wait for the socket to be readable or closed.
901 status_zx = stderr_socket_.wait_async(
902 port, kSocketKey, ZX_SOCKET_READABLE | ZX_SOCKET_PEER_CLOSED, 0);
903 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
904
905 // Register to wait for an exception.
906 status_zx = exception_channel_.wait_async(
907 port, kExceptionKey, ZX_CHANNEL_READABLE, 0);
908 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
909
910 bool process_terminated = false;
911 bool socket_closed = false;
912 do {
913 zx_port_packet_t packet = {};
914 status_zx = port.wait(zx::time::infinite(), &packet);
915 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
916
917 if (packet.key == kExceptionKey) {
918 // Process encountered an exception. Kill it directly rather than
919 // letting other handlers process the event. We will get a kProcessKey
920 // event when the process actually terminates.
921 status_zx = child_process_.kill();
922 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
923 } else if (packet.key == kProcessKey) {
924 // Process terminated.
925 GTEST_DEATH_TEST_CHECK_(ZX_PKT_IS_SIGNAL_ONE(packet.type));
926 GTEST_DEATH_TEST_CHECK_(packet.signal.observed & ZX_PROCESS_TERMINATED);
927 process_terminated = true;
928 } else if (packet.key == kSocketKey) {
929 GTEST_DEATH_TEST_CHECK_(ZX_PKT_IS_SIGNAL_ONE(packet.type));
930 if (packet.signal.observed & ZX_SOCKET_READABLE) {
931 // Read data from the socket.
932 constexpr size_t kBufferSize = 1024;
933 do {
934 size_t old_length = captured_stderr_.length();
935 size_t bytes_read = 0;
936 captured_stderr_.resize(old_length + kBufferSize);
937 status_zx = stderr_socket_.read(
938 0, &captured_stderr_.front() + old_length, kBufferSize,
939 &bytes_read);
940 captured_stderr_.resize(old_length + bytes_read);
941 } while (status_zx == ZX_OK);
942 if (status_zx == ZX_ERR_PEER_CLOSED) {
943 socket_closed = true;
944 } else {
945 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_ERR_SHOULD_WAIT);
946 status_zx = stderr_socket_.wait_async(
947 port, kSocketKey, ZX_SOCKET_READABLE | ZX_SOCKET_PEER_CLOSED, 0);
948 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
949 }
950 } else {
951 GTEST_DEATH_TEST_CHECK_(packet.signal.observed & ZX_SOCKET_PEER_CLOSED);
952 socket_closed = true;
953 }
954 }
955 } while (!process_terminated && !socket_closed);
956
957 ReadAndInterpretStatusByte();
958
959 zx_info_process_t buffer;
960 status_zx = child_process_.get_info(ZX_INFO_PROCESS, &buffer, sizeof(buffer),
961 nullptr, nullptr);
962 GTEST_DEATH_TEST_CHECK_(status_zx == ZX_OK);
963
964 GTEST_DEATH_TEST_CHECK_(buffer.flags & ZX_INFO_PROCESS_FLAG_EXITED);
965 set_status(static_cast<int>(buffer.return_code));
966 return status();
967}
968
969// The AssumeRole process for a Fuchsia death test. It creates a child
970// process with the same executable as the current process to run the
971// death test. The child process is given the --gtest_filter and
972// --gtest_internal_run_death_test flags such that it knows to run the
973// current death test only.
974DeathTest::TestRole FuchsiaDeathTest::AssumeRole() {
975 const UnitTestImpl* const impl = GetUnitTestImpl();
976 const InternalRunDeathTestFlag* const flag =
977 impl->internal_run_death_test_flag();
978 const TestInfo* const info = impl->current_test_info();
979 const int death_test_index = info->result()->death_test_count();
980
981 if (flag != nullptr) {
982 // ParseInternalRunDeathTestFlag() has performed all the necessary
983 // processing.
984 set_write_fd(kFuchsiaReadPipeFd);
985 return EXECUTE_TEST;
986 }
987
988 // Flush the log buffers since the log streams are shared with the child.
989 FlushInfoLog();
990
991 // Build the child process command line.
992 const std::string filter_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
993 "filter=" + info->test_suite_name() + "." +
994 info->name();
995 const std::string internal_flag =
996 std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag + "="
997 + file_ + "|"
998 + StreamableToString(line_) + "|"
999 + StreamableToString(death_test_index);
1000 Arguments args;
1001 args.AddArguments(GetInjectableArgvs());
1002 args.AddArgument(filter_flag.c_str());
1003 args.AddArgument(internal_flag.c_str());
1004
1005 // Build the pipe for communication with the child.
1006 zx_status_t status;
1007 zx_handle_t child_pipe_handle;
1008 int child_pipe_fd;
1009 status = fdio_pipe_half(&child_pipe_fd, &child_pipe_handle);
1010 GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
1011 set_read_fd(child_pipe_fd);
1012
1013 // Set the pipe handle for the child.
1014 fdio_spawn_action_t spawn_actions[2] = {};
1015 fdio_spawn_action_t* add_handle_action = &spawn_actions[0];
1016 add_handle_action->action = FDIO_SPAWN_ACTION_ADD_HANDLE;
1017 add_handle_action->h.id = PA_HND(PA_FD, kFuchsiaReadPipeFd);
1018 add_handle_action->h.handle = child_pipe_handle;
1019
1020 // Create a socket pair will be used to receive the child process' stderr.
1021 zx::socket stderr_producer_socket;
1022 status =
1023 zx::socket::create(0, &stderr_producer_socket, &stderr_socket_);
1024 GTEST_DEATH_TEST_CHECK_(status >= 0);
1025 int stderr_producer_fd = -1;
1026 status =
1027 fdio_fd_create(stderr_producer_socket.release(), &stderr_producer_fd);
1028 GTEST_DEATH_TEST_CHECK_(status >= 0);
1029
1030 // Make the stderr socket nonblocking.
1031 GTEST_DEATH_TEST_CHECK_(fcntl(stderr_producer_fd, F_SETFL, 0) == 0);
1032
1033 fdio_spawn_action_t* add_stderr_action = &spawn_actions[1];
1034 add_stderr_action->action = FDIO_SPAWN_ACTION_CLONE_FD;
1035 add_stderr_action->fd.local_fd = stderr_producer_fd;
1036 add_stderr_action->fd.target_fd = STDERR_FILENO;
1037
1038 // Create a child job.
1039 zx_handle_t child_job = ZX_HANDLE_INVALID;
1040 status = zx_job_create(zx_job_default(), 0, & child_job);
1041 GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
1042 zx_policy_basic_t policy;
1043 policy.condition = ZX_POL_NEW_ANY;
1044 policy.policy = ZX_POL_ACTION_ALLOW;
1045 status = zx_job_set_policy(
1046 child_job, ZX_JOB_POL_RELATIVE, ZX_JOB_POL_BASIC, &policy, 1);
1047 GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
1048
1049 // Create an exception channel attached to the |child_job|, to allow
1050 // us to suppress the system default exception handler from firing.
1051 status =
1052 zx_task_create_exception_channel(
1053 child_job, 0, exception_channel_.reset_and_get_address());
1054 GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
1055
1056 // Spawn the child process.
1057 status = fdio_spawn_etc(
1058 child_job, FDIO_SPAWN_CLONE_ALL, args.Argv()[0], args.Argv(), nullptr,
1059 2, spawn_actions, child_process_.reset_and_get_address(), nullptr);
1060 GTEST_DEATH_TEST_CHECK_(status == ZX_OK);
1061
1062 set_spawned(true);
1063 return OVERSEE_TEST;
1064}
1065
1066std::string FuchsiaDeathTest::GetErrorLogs() {
1067 return captured_stderr_;
1068}
1069
1070#else // We are neither on Windows, nor on Fuchsia.
1071
1072// ForkingDeathTest provides implementations for most of the abstract
1073// methods of the DeathTest interface. Only the AssumeRole method is
1074// left undefined.
1075class ForkingDeathTest : public DeathTestImpl {
1076 public:
1077 ForkingDeathTest(const char* statement, Matcher<const std::string&> matcher);
1078
1079 // All of these virtual functions are inherited from DeathTest.
1080 int Wait() override;
1081
1082 protected:
1083 void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }
1084
1085 private:
1086 // PID of child process during death test; 0 in the child process itself.
1087 pid_t child_pid_;
1088};
1089
1090// Constructs a ForkingDeathTest.
1091ForkingDeathTest::ForkingDeathTest(const char* a_statement,
1092 Matcher<const std::string&> matcher)
1093 : DeathTestImpl(a_statement, std::move(matcher)), child_pid_(-1) {}
1094
1095// Waits for the child in a death test to exit, returning its exit
1096// status, or 0 if no child process exists. As a side effect, sets the
1097// outcome data member.
1098int ForkingDeathTest::Wait() {
1099 if (!spawned())
1100 return 0;
1101
1102 ReadAndInterpretStatusByte();
1103
1104 int status_value;
1105 GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status_value, 0));
1106 set_status(status_value);
1107 return status_value;
1108}
1109
1110// A concrete death test class that forks, then immediately runs the test
1111// in the child process.
1112class NoExecDeathTest : public ForkingDeathTest {
1113 public:
1114 NoExecDeathTest(const char* a_statement, Matcher<const std::string&> matcher)
1115 : ForkingDeathTest(a_statement, std::move(matcher)) {}
1116 TestRole AssumeRole() override;
1117};
1118
1119// The AssumeRole process for a fork-and-run death test. It implements a
1120// straightforward fork, with a simple pipe to transmit the status byte.
1121DeathTest::TestRole NoExecDeathTest::AssumeRole() {
1122 const size_t thread_count = GetThreadCount();
1123 if (thread_count != 1) {
1124 GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);
1125 }
1126
1127 int pipe_fd[2];
1128 GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
1129
1130 DeathTest::set_last_death_test_message("");
1131 CaptureStderr();
1132 // When we fork the process below, the log file buffers are copied, but the
1133 // file descriptors are shared. We flush all log files here so that closing
1134 // the file descriptors in the child process doesn't throw off the
1135 // synchronization between descriptors and buffers in the parent process.
1136 // This is as close to the fork as possible to avoid a race condition in case
1137 // there are multiple threads running before the death test, and another
1138 // thread writes to the log file.
1139 FlushInfoLog();
1140
1141 const pid_t child_pid = fork();
1142 GTEST_DEATH_TEST_CHECK_(child_pid != -1);
1143 set_child_pid(child_pid);
1144 if (child_pid == 0) {
1145 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));
1146 set_write_fd(pipe_fd[1]);
1147 // Redirects all logging to stderr in the child process to prevent
1148 // concurrent writes to the log files. We capture stderr in the parent
1149 // process and append the child process' output to a log.
1150 LogToStderr();
1151 // Event forwarding to the listeners of event listener API mush be shut
1152 // down in death test subprocesses.
1153 GetUnitTestImpl()->listeners()->SuppressEventForwarding();
1154 g_in_fast_death_test_child = true;
1155 return EXECUTE_TEST;
1156 } else {
1157 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
1158 set_read_fd(pipe_fd[0]);
1159 set_spawned(true);
1160 return OVERSEE_TEST;
1161 }
1162}
1163
1164// A concrete death test class that forks and re-executes the main
1165// program from the beginning, with command-line flags set that cause
1166// only this specific death test to be run.
1167class ExecDeathTest : public ForkingDeathTest {
1168 public:
1169 ExecDeathTest(const char* a_statement, Matcher<const std::string&> matcher,
1170 const char* file, int line)
1171 : ForkingDeathTest(a_statement, std::move(matcher)),
1172 file_(file),
1173 line_(line) {}
1174 TestRole AssumeRole() override;
1175
1176 private:
1177 static ::std::vector<std::string> GetArgvsForDeathTestChildProcess() {
1178 ::std::vector<std::string> args = GetInjectableArgvs();
1179# if defined(GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_)
1180 ::std::vector<std::string> extra_args =
1181 GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_();
1182 args.insert(args.end(), extra_args.begin(), extra_args.end());
1183# endif // defined(GTEST_EXTRA_DEATH_TEST_COMMAND_LINE_ARGS_)
1184 return args;
1185 }
1186 // The name of the file in which the death test is located.
1187 const char* const file_;
1188 // The line number on which the death test is located.
1189 const int line_;
1190};
1191
1192// Utility class for accumulating command-line arguments.
1193class Arguments {
1194 public:
1195 Arguments() { args_.push_back(x: nullptr); }
1196
1197 ~Arguments() {
1198 for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
1199 ++i) {
1200 free(ptr: *i);
1201 }
1202 }
1203 void AddArgument(const char* argument) {
1204 args_.insert(position: args_.end() - 1, x: posix::StrDup(src: argument));
1205 }
1206
1207 template <typename Str>
1208 void AddArguments(const ::std::vector<Str>& arguments) {
1209 for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
1210 i != arguments.end();
1211 ++i) {
1212 args_.insert(args_.end() - 1, posix::StrDup(src: i->c_str()));
1213 }
1214 }
1215 char* const* Argv() {
1216 return &args_[0];
1217 }
1218
1219 private:
1220 std::vector<char*> args_;
1221};
1222
1223// A struct that encompasses the arguments to the child process of a
1224// threadsafe-style death test process.
1225struct ExecDeathTestArgs {
1226 char* const* argv; // Command-line arguments for the child's call to exec
1227 int close_fd; // File descriptor to close; the read end of a pipe
1228};
1229
1230# if GTEST_OS_QNX
1231extern "C" char** environ;
1232# else // GTEST_OS_QNX
1233// The main function for a threadsafe-style death test child process.
1234// This function is called in a clone()-ed process and thus must avoid
1235// any potentially unsafe operations like malloc or libc functions.
1236static int ExecDeathTestChildMain(void* child_arg) {
1237 ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg);
1238 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));
1239
1240 // We need to execute the test program in the same environment where
1241 // it was originally invoked. Therefore we change to the original
1242 // working directory first.
1243 const char* const original_dir =
1244 UnitTest::GetInstance()->original_working_dir();
1245 // We can safely call chdir() as it's a direct system call.
1246 if (chdir(path: original_dir) != 0) {
1247 DeathTestAbort(message: std::string("chdir(\"") + original_dir + "\") failed: " +
1248 GetLastErrnoDescription());
1249 return EXIT_FAILURE;
1250 }
1251
1252 // We can safely call execv() as it's almost a direct system call. We
1253 // cannot use execvp() as it's a libc function and thus potentially
1254 // unsafe. Since execv() doesn't search the PATH, the user must
1255 // invoke the test program via a valid path that contains at least
1256 // one path separator.
1257 execv(path: args->argv[0], argv: args->argv);
1258 DeathTestAbort(message: std::string("execv(") + args->argv[0] + ", ...) in " +
1259 original_dir + " failed: " +
1260 GetLastErrnoDescription());
1261 return EXIT_FAILURE;
1262}
1263# endif // GTEST_OS_QNX
1264
1265# if GTEST_HAS_CLONE
1266// Two utility routines that together determine the direction the stack
1267// grows.
1268// This could be accomplished more elegantly by a single recursive
1269// function, but we want to guard against the unlikely possibility of
1270// a smart compiler optimizing the recursion away.
1271//
1272// GTEST_NO_INLINE_ is required to prevent GCC 4.6 from inlining
1273// StackLowerThanAddress into StackGrowsDown, which then doesn't give
1274// correct answer.
1275static void StackLowerThanAddress(const void* ptr,
1276 bool* result) GTEST_NO_INLINE_;
1277// Make sure sanitizers do not tamper with the stack here.
1278// Ideally, we want to use `__builtin_frame_address` instead of a local variable
1279// address with sanitizer disabled, but it does not work when the
1280// compiler optimizes the stack frame out, which happens on PowerPC targets.
1281// HWAddressSanitizer add a random tag to the MSB of the local variable address,
1282// making comparison result unpredictable.
1283GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
1284GTEST_ATTRIBUTE_NO_SANITIZE_HWADDRESS_
1285static void StackLowerThanAddress(const void* ptr, bool* result) {
1286 int dummy = 0;
1287 *result = std::less<const void*>()(&dummy, ptr);
1288}
1289
1290// Make sure AddressSanitizer does not tamper with the stack here.
1291GTEST_ATTRIBUTE_NO_SANITIZE_ADDRESS_
1292GTEST_ATTRIBUTE_NO_SANITIZE_HWADDRESS_
1293static bool StackGrowsDown() {
1294 int dummy = 0;
1295 bool result;
1296 StackLowerThanAddress(ptr: &dummy, result: &result);
1297 return result;
1298}
1299# endif // GTEST_HAS_CLONE
1300
1301// Spawns a child process with the same executable as the current process in
1302// a thread-safe manner and instructs it to run the death test. The
1303// implementation uses fork(2) + exec. On systems where clone(2) is
1304// available, it is used instead, being slightly more thread-safe. On QNX,
1305// fork supports only single-threaded environments, so this function uses
1306// spawn(2) there instead. The function dies with an error message if
1307// anything goes wrong.
1308static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
1309 ExecDeathTestArgs args = { .argv: argv, .close_fd: close_fd };
1310 pid_t child_pid = -1;
1311
1312# if GTEST_OS_QNX
1313 // Obtains the current directory and sets it to be closed in the child
1314 // process.
1315 const int cwd_fd = open(".", O_RDONLY);
1316 GTEST_DEATH_TEST_CHECK_(cwd_fd != -1);
1317 GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(cwd_fd, F_SETFD, FD_CLOEXEC));
1318 // We need to execute the test program in the same environment where
1319 // it was originally invoked. Therefore we change to the original
1320 // working directory first.
1321 const char* const original_dir =
1322 UnitTest::GetInstance()->original_working_dir();
1323 // We can safely call chdir() as it's a direct system call.
1324 if (chdir(original_dir) != 0) {
1325 DeathTestAbort(std::string("chdir(\"") + original_dir + "\") failed: " +
1326 GetLastErrnoDescription());
1327 return EXIT_FAILURE;
1328 }
1329
1330 int fd_flags;
1331 // Set close_fd to be closed after spawn.
1332 GTEST_DEATH_TEST_CHECK_SYSCALL_(fd_flags = fcntl(close_fd, F_GETFD));
1333 GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(close_fd, F_SETFD,
1334 fd_flags | FD_CLOEXEC));
1335 struct inheritance inherit = {0};
1336 // spawn is a system call.
1337 child_pid = spawn(args.argv[0], 0, nullptr, &inherit, args.argv, environ);
1338 // Restores the current working directory.
1339 GTEST_DEATH_TEST_CHECK_(fchdir(cwd_fd) != -1);
1340 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(cwd_fd));
1341
1342# else // GTEST_OS_QNX
1343# if GTEST_OS_LINUX
1344 // When a SIGPROF signal is received while fork() or clone() are executing,
1345 // the process may hang. To avoid this, we ignore SIGPROF here and re-enable
1346 // it after the call to fork()/clone() is complete.
1347 struct sigaction saved_sigprof_action;
1348 struct sigaction ignore_sigprof_action;
1349 memset(s: &ignore_sigprof_action, c: 0, n: sizeof(ignore_sigprof_action));
1350 sigemptyset(set: &ignore_sigprof_action.sa_mask);
1351 ignore_sigprof_action.sa_handler = SIG_IGN;
1352 GTEST_DEATH_TEST_CHECK_SYSCALL_(sigaction(
1353 SIGPROF, &ignore_sigprof_action, &saved_sigprof_action));
1354# endif // GTEST_OS_LINUX
1355
1356# if GTEST_HAS_CLONE
1357 const bool use_fork = GTEST_FLAG_GET(death_test_use_fork);
1358
1359 if (!use_fork) {
1360 static const bool stack_grows_down = StackGrowsDown();
1361 const auto stack_size = static_cast<size_t>(getpagesize() * 2);
1362 // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
1363 void* const stack = mmap(addr: nullptr, len: stack_size, PROT_READ | PROT_WRITE,
1364 MAP_ANON | MAP_PRIVATE, fd: -1, offset: 0);
1365 GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
1366
1367 // Maximum stack alignment in bytes: For a downward-growing stack, this
1368 // amount is subtracted from size of the stack space to get an address
1369 // that is within the stack space and is aligned on all systems we care
1370 // about. As far as I know there is no ABI with stack alignment greater
1371 // than 64. We assume stack and stack_size already have alignment of
1372 // kMaxStackAlignment.
1373 const size_t kMaxStackAlignment = 64;
1374 void* const stack_top =
1375 static_cast<char*>(stack) +
1376 (stack_grows_down ? stack_size - kMaxStackAlignment : 0);
1377 GTEST_DEATH_TEST_CHECK_(
1378 static_cast<size_t>(stack_size) > kMaxStackAlignment &&
1379 reinterpret_cast<uintptr_t>(stack_top) % kMaxStackAlignment == 0);
1380
1381 child_pid = clone(fn: &ExecDeathTestChildMain, child_stack: stack_top, SIGCHLD, arg: &args);
1382
1383 GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
1384 }
1385# else
1386 const bool use_fork = true;
1387# endif // GTEST_HAS_CLONE
1388
1389 if (use_fork && (child_pid = fork()) == 0) {
1390 ExecDeathTestChildMain(child_arg: &args);
1391 _exit(status: 0);
1392 }
1393# endif // GTEST_OS_QNX
1394# if GTEST_OS_LINUX
1395 GTEST_DEATH_TEST_CHECK_SYSCALL_(
1396 sigaction(SIGPROF, &saved_sigprof_action, nullptr));
1397# endif // GTEST_OS_LINUX
1398
1399 GTEST_DEATH_TEST_CHECK_(child_pid != -1);
1400 return child_pid;
1401}
1402
1403// The AssumeRole process for a fork-and-exec death test. It re-executes the
1404// main program from the beginning, setting the --gtest_filter
1405// and --gtest_internal_run_death_test flags to cause only the current
1406// death test to be re-run.
1407DeathTest::TestRole ExecDeathTest::AssumeRole() {
1408 const UnitTestImpl* const impl = GetUnitTestImpl();
1409 const InternalRunDeathTestFlag* const flag =
1410 impl->internal_run_death_test_flag();
1411 const TestInfo* const info = impl->current_test_info();
1412 const int death_test_index = info->result()->death_test_count();
1413
1414 if (flag != nullptr) {
1415 set_write_fd(flag->write_fd());
1416 return EXECUTE_TEST;
1417 }
1418
1419 int pipe_fd[2];
1420 GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
1421 // Clear the close-on-exec flag on the write end of the pipe, lest
1422 // it be closed when the child process does an exec:
1423 GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
1424
1425 const std::string filter_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
1426 "filter=" + info->test_suite_name() + "." +
1427 info->name();
1428 const std::string internal_flag = std::string("--") + GTEST_FLAG_PREFIX_ +
1429 "internal_run_death_test=" + file_ + "|" +
1430 StreamableToString(streamable: line_) + "|" +
1431 StreamableToString(streamable: death_test_index) + "|" +
1432 StreamableToString(streamable: pipe_fd[1]);
1433 Arguments args;
1434 args.AddArguments(arguments: GetArgvsForDeathTestChildProcess());
1435 args.AddArgument(argument: filter_flag.c_str());
1436 args.AddArgument(argument: internal_flag.c_str());
1437
1438 DeathTest::set_last_death_test_message("");
1439
1440 CaptureStderr();
1441 // See the comment in NoExecDeathTest::AssumeRole for why the next line
1442 // is necessary.
1443 FlushInfoLog();
1444
1445 const pid_t child_pid = ExecDeathTestSpawnChild(argv: args.Argv(), close_fd: pipe_fd[0]);
1446 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
1447 set_child_pid(child_pid);
1448 set_read_fd(pipe_fd[0]);
1449 set_spawned(true);
1450 return OVERSEE_TEST;
1451}
1452
1453# endif // !GTEST_OS_WINDOWS
1454
1455// Creates a concrete DeathTest-derived class that depends on the
1456// --gtest_death_test_style flag, and sets the pointer pointed to
1457// by the "test" argument to its address. If the test should be
1458// skipped, sets that pointer to NULL. Returns true, unless the
1459// flag is set to an invalid value.
1460bool DefaultDeathTestFactory::Create(const char* statement,
1461 Matcher<const std::string&> matcher,
1462 const char* file, int line,
1463 DeathTest** test) {
1464 UnitTestImpl* const impl = GetUnitTestImpl();
1465 const InternalRunDeathTestFlag* const flag =
1466 impl->internal_run_death_test_flag();
1467 const int death_test_index = impl->current_test_info()
1468 ->increment_death_test_count();
1469
1470 if (flag != nullptr) {
1471 if (death_test_index > flag->index()) {
1472 DeathTest::set_last_death_test_message(
1473 "Death test count (" + StreamableToString(streamable: death_test_index)
1474 + ") somehow exceeded expected maximum ("
1475 + StreamableToString(streamable: flag->index()) + ")");
1476 return false;
1477 }
1478
1479 if (!(flag->file() == file && flag->line() == line &&
1480 flag->index() == death_test_index)) {
1481 *test = nullptr;
1482 return true;
1483 }
1484 }
1485
1486# if GTEST_OS_WINDOWS
1487
1488 if (GTEST_FLAG_GET(death_test_style) == "threadsafe" ||
1489 GTEST_FLAG_GET(death_test_style) == "fast") {
1490 *test = new WindowsDeathTest(statement, std::move(matcher), file, line);
1491 }
1492
1493# elif GTEST_OS_FUCHSIA
1494
1495 if (GTEST_FLAG_GET(death_test_style) == "threadsafe" ||
1496 GTEST_FLAG_GET(death_test_style) == "fast") {
1497 *test = new FuchsiaDeathTest(statement, std::move(matcher), file, line);
1498 }
1499
1500# else
1501
1502 if (GTEST_FLAG_GET(death_test_style) == "threadsafe") {
1503 *test = new ExecDeathTest(statement, std::move(matcher), file, line);
1504 } else if (GTEST_FLAG_GET(death_test_style) == "fast") {
1505 *test = new NoExecDeathTest(statement, std::move(matcher));
1506 }
1507
1508# endif // GTEST_OS_WINDOWS
1509
1510 else { // NOLINT - this is more readable than unbalanced brackets inside #if.
1511 DeathTest::set_last_death_test_message("Unknown death test style \"" +
1512 GTEST_FLAG_GET(death_test_style) +
1513 "\" encountered");
1514 return false;
1515 }
1516
1517 return true;
1518}
1519
1520# if GTEST_OS_WINDOWS
1521// Recreates the pipe and event handles from the provided parameters,
1522// signals the event, and returns a file descriptor wrapped around the pipe
1523// handle. This function is called in the child process only.
1524static int GetStatusFileDescriptor(unsigned int parent_process_id,
1525 size_t write_handle_as_size_t,
1526 size_t event_handle_as_size_t) {
1527 AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
1528 FALSE, // Non-inheritable.
1529 parent_process_id));
1530 if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
1531 DeathTestAbort("Unable to open parent process " +
1532 StreamableToString(parent_process_id));
1533 }
1534
1535 GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));
1536
1537 const HANDLE write_handle =
1538 reinterpret_cast<HANDLE>(write_handle_as_size_t);
1539 HANDLE dup_write_handle;
1540
1541 // The newly initialized handle is accessible only in the parent
1542 // process. To obtain one accessible within the child, we need to use
1543 // DuplicateHandle.
1544 if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
1545 ::GetCurrentProcess(), &dup_write_handle,
1546 0x0, // Requested privileges ignored since
1547 // DUPLICATE_SAME_ACCESS is used.
1548 FALSE, // Request non-inheritable handler.
1549 DUPLICATE_SAME_ACCESS)) {
1550 DeathTestAbort("Unable to duplicate the pipe handle " +
1551 StreamableToString(write_handle_as_size_t) +
1552 " from the parent process " +
1553 StreamableToString(parent_process_id));
1554 }
1555
1556 const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
1557 HANDLE dup_event_handle;
1558
1559 if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
1560 ::GetCurrentProcess(), &dup_event_handle,
1561 0x0,
1562 FALSE,
1563 DUPLICATE_SAME_ACCESS)) {
1564 DeathTestAbort("Unable to duplicate the event handle " +
1565 StreamableToString(event_handle_as_size_t) +
1566 " from the parent process " +
1567 StreamableToString(parent_process_id));
1568 }
1569
1570 const int write_fd =
1571 ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
1572 if (write_fd == -1) {
1573 DeathTestAbort("Unable to convert pipe handle " +
1574 StreamableToString(write_handle_as_size_t) +
1575 " to a file descriptor");
1576 }
1577
1578 // Signals the parent that the write end of the pipe has been acquired
1579 // so the parent can release its own write end.
1580 ::SetEvent(dup_event_handle);
1581
1582 return write_fd;
1583}
1584# endif // GTEST_OS_WINDOWS
1585
1586// Returns a newly created InternalRunDeathTestFlag object with fields
1587// initialized from the GTEST_FLAG(internal_run_death_test) flag if
1588// the flag is specified; otherwise returns NULL.
1589InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
1590 if (GTEST_FLAG_GET(internal_run_death_test) == "") return nullptr;
1591
1592 // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
1593 // can use it here.
1594 int line = -1;
1595 int index = -1;
1596 ::std::vector< ::std::string> fields;
1597 SplitString(GTEST_FLAG_GET(internal_run_death_test), delimiter: '|', dest: &fields);
1598 int write_fd = -1;
1599
1600# if GTEST_OS_WINDOWS
1601
1602 unsigned int parent_process_id = 0;
1603 size_t write_handle_as_size_t = 0;
1604 size_t event_handle_as_size_t = 0;
1605
1606 if (fields.size() != 6
1607 || !ParseNaturalNumber(fields[1], &line)
1608 || !ParseNaturalNumber(fields[2], &index)
1609 || !ParseNaturalNumber(fields[3], &parent_process_id)
1610 || !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
1611 || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
1612 DeathTestAbort("Bad --gtest_internal_run_death_test flag: " +
1613 GTEST_FLAG_GET(internal_run_death_test));
1614 }
1615 write_fd = GetStatusFileDescriptor(parent_process_id,
1616 write_handle_as_size_t,
1617 event_handle_as_size_t);
1618
1619# elif GTEST_OS_FUCHSIA
1620
1621 if (fields.size() != 3
1622 || !ParseNaturalNumber(fields[1], &line)
1623 || !ParseNaturalNumber(fields[2], &index)) {
1624 DeathTestAbort("Bad --gtest_internal_run_death_test flag: " +
1625 GTEST_FLAG_GET(internal_run_death_test));
1626 }
1627
1628# else
1629
1630 if (fields.size() != 4
1631 || !ParseNaturalNumber(str: fields[1], number: &line)
1632 || !ParseNaturalNumber(str: fields[2], number: &index)
1633 || !ParseNaturalNumber(str: fields[3], number: &write_fd)) {
1634 DeathTestAbort(message: "Bad --gtest_internal_run_death_test flag: " +
1635 GTEST_FLAG_GET(internal_run_death_test));
1636 }
1637
1638# endif // GTEST_OS_WINDOWS
1639
1640 return new InternalRunDeathTestFlag(fields[0], line, index, write_fd);
1641}
1642
1643} // namespace internal
1644
1645#endif // GTEST_HAS_DEATH_TEST
1646
1647} // namespace testing
1648

source code of flutter_engine/third_party/googletest/googletest/src/gtest-death-test.cc