/Unittests/googletest/src/gtest-death-test.cc
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1// Copyright 2005, Google Inc. 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are 6// met: 7// 8// * Redistributions of source code must retain the above copyright 9// notice, this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above 11// copyright notice, this list of conditions and the following disclaimer 12// in the documentation and/or other materials provided with the 13// distribution. 14// * Neither the name of Google Inc. nor the names of its 15// contributors may be used to endorse or promote products derived from 16// this software without specific prior written permission. 17// 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 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#include <stdarg.h> 47 48#if GTEST_OS_WINDOWS 49#include <windows.h> 50#else 51#include <sys/mman.h> 52#include <sys/wait.h> 53#endif // GTEST_OS_WINDOWS 54 55#endif // GTEST_HAS_DEATH_TEST 56 57#include <gtest/gtest-message.h> 58#include <gtest/internal/gtest-string.h> 59 60// Indicates that this translation unit is part of Google Test's 61// implementation. It must come before gtest-internal-inl.h is 62// included, or there will be a compiler error. This trick is to 63// prevent a user from accidentally including gtest-internal-inl.h in 64// his code. 65#define GTEST_IMPLEMENTATION_ 1 66#include "src/gtest-internal-inl.h" 67#undef GTEST_IMPLEMENTATION_ 68 69namespace testing { 70 71// Constants. 72 73// The default death test style. 74static const char kDefaultDeathTestStyle[] = "fast"; 75 76GTEST_DEFINE_string_( 77 death_test_style, 78 internal::StringFromGTestEnv("death_test_style", kDefaultDeathTestStyle), 79 "Indicates how to run a death test in a forked child process: " 80 "\"threadsafe\" (child process re-executes the test binary " 81 "from the beginning, running only the specific death test) or " 82 "\"fast\" (child process runs the death test immediately " 83 "after forking)."); 84 85GTEST_DEFINE_bool_( 86 death_test_use_fork, 87 internal::BoolFromGTestEnv("death_test_use_fork", false), 88 "Instructs to use fork()/_exit() instead of clone() in death tests. " 89 "Ignored and always uses fork() on POSIX systems where clone() is not " 90 "implemented. Useful when running under valgrind or similar tools if " 91 "those do not support clone(). Valgrind 3.3.1 will just fail if " 92 "it sees an unsupported combination of clone() flags. " 93 "It is not recommended to use this flag w/o valgrind though it will " 94 "work in 99% of the cases. Once valgrind is fixed, this flag will " 95 "most likely be removed."); 96 97namespace internal { 98GTEST_DEFINE_string_( 99 internal_run_death_test, "", 100 "Indicates the file, line number, temporal index of " 101 "the single death test to run, and a file descriptor to " 102 "which a success code may be sent, all separated by " 103 "colons. This flag is specified if and only if the current " 104 "process is a sub-process launched for running a thread-safe " 105 "death test. FOR INTERNAL USE ONLY."); 106} // namespace internal 107 108#if GTEST_HAS_DEATH_TEST 109 110// ExitedWithCode constructor. 111ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) { 112} 113 114// ExitedWithCode function-call operator. 115bool ExitedWithCode::operator()(int exit_status) const { 116#if GTEST_OS_WINDOWS 117 return exit_status == exit_code_; 118#else 119 return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_; 120#endif // GTEST_OS_WINDOWS 121} 122 123#if !GTEST_OS_WINDOWS 124// KilledBySignal constructor. 125KilledBySignal::KilledBySignal(int signum) : signum_(signum) { 126} 127 128// KilledBySignal function-call operator. 129bool KilledBySignal::operator()(int exit_status) const { 130 return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_; 131} 132#endif // !GTEST_OS_WINDOWS 133 134namespace internal { 135 136// Utilities needed for death tests. 137 138// Generates a textual description of a given exit code, in the format 139// specified by wait(2). 140static String ExitSummary(int exit_code) { 141 Message m; 142#if GTEST_OS_WINDOWS 143 m << "Exited with exit status " << exit_code; 144#else 145 if (WIFEXITED(exit_code)) { 146 m << "Exited with exit status " << WEXITSTATUS(exit_code); 147 } else if (WIFSIGNALED(exit_code)) { 148 m << "Terminated by signal " << WTERMSIG(exit_code); 149 } 150#ifdef WCOREDUMP 151 if (WCOREDUMP(exit_code)) { 152 m << " (core dumped)"; 153 } 154#endif 155#endif // GTEST_OS_WINDOWS 156 return m.GetString(); 157} 158 159// Returns true if exit_status describes a process that was terminated 160// by a signal, or exited normally with a nonzero exit code. 161bool ExitedUnsuccessfully(int exit_status) { 162 return !ExitedWithCode(0)(exit_status); 163} 164 165#if !GTEST_OS_WINDOWS 166// Generates a textual failure message when a death test finds more than 167// one thread running, or cannot determine the number of threads, prior 168// to executing the given statement. It is the responsibility of the 169// caller not to pass a thread_count of 1. 170static String DeathTestThreadWarning(size_t thread_count) { 171 Message msg; 172 msg << "Death tests use fork(), which is unsafe particularly" 173 << " in a threaded context. For this test, " << GTEST_NAME_ << " "; 174 if (thread_count == 0) 175 msg << "couldn't detect the number of threads."; 176 else 177 msg << "detected " << thread_count << " threads."; 178 return msg.GetString(); 179} 180#endif // !GTEST_OS_WINDOWS 181 182// Flag characters for reporting a death test that did not die. 183static const char kDeathTestLived = 'L'; 184static const char kDeathTestReturned = 'R'; 185static const char kDeathTestInternalError = 'I'; 186 187// An enumeration describing all of the possible ways that a death test 188// can conclude. DIED means that the process died while executing the 189// test code; LIVED means that process lived beyond the end of the test 190// code; and RETURNED means that the test statement attempted a "return," 191// which is not allowed. IN_PROGRESS means the test has not yet 192// concluded. 193enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED }; 194 195// Routine for aborting the program which is safe to call from an 196// exec-style death test child process, in which case the error 197// message is propagated back to the parent process. Otherwise, the 198// message is simply printed to stderr. In either case, the program 199// then exits with status 1. 200void DeathTestAbort(const String& message) { 201 // On a POSIX system, this function may be called from a threadsafe-style 202 // death test child process, which operates on a very small stack. Use 203 // the heap for any additional non-minuscule memory requirements. 204 const InternalRunDeathTestFlag* const flag = 205 GetUnitTestImpl()->internal_run_death_test_flag(); 206 if (flag != NULL) { 207 FILE* parent = posix::FDOpen(flag->write_fd(), "w"); 208 fputc(kDeathTestInternalError, parent); 209 fprintf(parent, "%s", message.c_str()); 210 fflush(parent); 211 _exit(1); 212 } else { 213 fprintf(stderr, "%s", message.c_str()); 214 fflush(stderr); 215 abort(); 216 } 217} 218 219// A replacement for CHECK that calls DeathTestAbort if the assertion 220// fails. 221#define GTEST_DEATH_TEST_CHECK_(expression) \ 222 do { \ 223 if (!::testing::internal::IsTrue(expression)) { \ 224 DeathTestAbort(::testing::internal::String::Format( \ 225 "CHECK failed: File %s, line %d: %s", \ 226 __FILE__, __LINE__, #expression)); \ 227 } \ 228 } while (::testing::internal::AlwaysFalse()) 229 230// This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for 231// evaluating any system call that fulfills two conditions: it must return 232// -1 on failure, and set errno to EINTR when it is interrupted and 233// should be tried again. The macro expands to a loop that repeatedly 234// evaluates the expression as long as it evaluates to -1 and sets 235// errno to EINTR. If the expression evaluates to -1 but errno is 236// something other than EINTR, DeathTestAbort is called. 237#define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \ 238 do { \ 239 int gtest_retval; \ 240 do { \ 241 gtest_retval = (expression); \ 242 } while (gtest_retval == -1 && errno == EINTR); \ 243 if (gtest_retval == -1) { \ 244 DeathTestAbort(::testing::internal::String::Format( \ 245 "CHECK failed: File %s, line %d: %s != -1", \ 246 __FILE__, __LINE__, #expression)); \ 247 } \ 248 } while (::testing::internal::AlwaysFalse()) 249 250// Returns the message describing the last system error in errno. 251String GetLastErrnoDescription() { 252 return String(errno == 0 ? "" : posix::StrError(errno)); 253} 254 255// This is called from a death test parent process to read a failure 256// message from the death test child process and log it with the FATAL 257// severity. On Windows, the message is read from a pipe handle. On other 258// platforms, it is read from a file descriptor. 259static void FailFromInternalError(int fd) { 260 Message error; 261 char buffer[256]; 262 int num_read; 263 264 do { 265 while ((num_read = posix::Read(fd, buffer, 255)) > 0) { 266 buffer[num_read] = '\0'; 267 error << buffer; 268 } 269 } while (num_read == -1 && errno == EINTR); 270 271 if (num_read == 0) { 272 GTEST_LOG_(FATAL) << error.GetString(); 273 } else { 274 const int last_error = errno; 275 GTEST_LOG_(FATAL) << "Error while reading death test internal: " 276 << GetLastErrnoDescription() << " [" << last_error << "]"; 277 } 278} 279 280// Death test constructor. Increments the running death test count 281// for the current test. 282DeathTest::DeathTest() { 283 TestInfo* const info = GetUnitTestImpl()->current_test_info(); 284 if (info == NULL) { 285 DeathTestAbort("Cannot run a death test outside of a TEST or " 286 "TEST_F construct"); 287 } 288} 289 290// Creates and returns a death test by dispatching to the current 291// death test factory. 292bool DeathTest::Create(const char* statement, const RE* regex, 293 const char* file, int line, DeathTest** test) { 294 return GetUnitTestImpl()->death_test_factory()->Create( 295 statement, regex, file, line, test); 296} 297 298const char* DeathTest::LastMessage() { 299 return last_death_test_message_.c_str(); 300} 301 302void DeathTest::set_last_death_test_message(const String& message) { 303 last_death_test_message_ = message; 304} 305 306String DeathTest::last_death_test_message_; 307 308// Provides cross platform implementation for some death functionality. 309class DeathTestImpl : public DeathTest { 310 protected: 311 DeathTestImpl(const char* statement, const RE* regex) 312 : statement_(statement), 313 regex_(regex), 314 spawned_(false), 315 status_(-1), 316 outcome_(IN_PROGRESS), 317 read_fd_(-1), 318 write_fd_(-1) {} 319 320 // read_fd_ is expected to be closed and cleared by a derived class. 321 ~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); } 322 323 void Abort(AbortReason reason); 324 virtual bool Passed(bool status_ok); 325 326 const char* statement() const { return statement_; } 327 const RE* regex() const { return regex_; } 328 bool spawned() const { return spawned_; } 329 void set_spawned(bool spawned) { spawned_ = spawned; } 330 int status() const { return status_; } 331 void set_status(int status) { status_ = status; } 332 DeathTestOutcome outcome() const { return outcome_; } 333 void set_outcome(DeathTestOutcome outcome) { outcome_ = outcome; } 334 int read_fd() const { return read_fd_; } 335 void set_read_fd(int fd) { read_fd_ = fd; } 336 int write_fd() const { return write_fd_; } 337 void set_write_fd(int fd) { write_fd_ = fd; } 338 339 // Called in the parent process only. Reads the result code of the death 340 // test child process via a pipe, interprets it to set the outcome_ 341 // member, and closes read_fd_. Outputs diagnostics and terminates in 342 // case of unexpected codes. 343 void ReadAndInterpretStatusByte(); 344 345 private: 346 // The textual content of the code this object is testing. This class 347 // doesn't own this string and should not attempt to delete it. 348 const char* const statement_; 349 // The regular expression which test output must match. DeathTestImpl 350 // doesn't own this object and should not attempt to delete it. 351 const RE* const regex_; 352 // True if the death test child process has been successfully spawned. 353 bool spawned_; 354 // The exit status of the child process. 355 int status_; 356 // How the death test concluded. 357 DeathTestOutcome outcome_; 358 // Descriptor to the read end of the pipe to the child process. It is 359 // always -1 in the child process. The child keeps its write end of the 360 // pipe in write_fd_. 361 int read_fd_; 362 // Descriptor to the child's write end of the pipe to the parent process. 363 // It is always -1 in the parent process. The parent keeps its end of the 364 // pipe in read_fd_. 365 int write_fd_; 366}; 367 368// Called in the parent process only. Reads the result code of the death 369// test child process via a pipe, interprets it to set the outcome_ 370// member, and closes read_fd_. Outputs diagnostics and terminates in 371// case of unexpected codes. 372void DeathTestImpl::ReadAndInterpretStatusByte() { 373 char flag; 374 int bytes_read; 375 376 // The read() here blocks until data is available (signifying the 377 // failure of the death test) or until the pipe is closed (signifying 378 // its success), so it's okay to call this in the parent before 379 // the child process has exited. 380 do { 381 bytes_read = posix::Read(read_fd(), &flag, 1); 382 } while (bytes_read == -1 && errno == EINTR); 383 384 if (bytes_read == 0) { 385 set_outcome(DIED); 386 } else if (bytes_read == 1) { 387 switch (flag) { 388 case kDeathTestReturned: 389 set_outcome(RETURNED); 390 break; 391 case kDeathTestLived: 392 set_outcome(LIVED); 393 break; 394 case kDeathTestInternalError: 395 FailFromInternalError(read_fd()); // Does not return. 396 break; 397 default: 398 GTEST_LOG_(FATAL) << "Death test child process reported " 399 << "unexpected status byte (" 400 << static_cast<unsigned int>(flag) << ")"; 401 } 402 } else { 403 GTEST_LOG_(FATAL) << "Read from death test child process failed: " 404 << GetLastErrnoDescription(); 405 } 406 GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd())); 407 set_read_fd(-1); 408} 409 410// Signals that the death test code which should have exited, didn't. 411// Should be called only in a death test child process. 412// Writes a status byte to the child's status file descriptor, then 413// calls _exit(1). 414void DeathTestImpl::Abort(AbortReason reason) { 415 // The parent process considers the death test to be a failure if 416 // it finds any data in our pipe. So, here we write a single flag byte 417 // to the pipe, then exit. 418 const char status_ch = 419 reason == TEST_DID_NOT_DIE ? kDeathTestLived : kDeathTestReturned; 420 GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1)); 421 GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(write_fd())); 422 _exit(1); // Exits w/o any normal exit hooks (we were supposed to crash) 423} 424 425// Assesses the success or failure of a death test, using both private 426// members which have previously been set, and one argument: 427// 428// Private data members: 429// outcome: An enumeration describing how the death test 430// concluded: DIED, LIVED, or RETURNED. The death test fails 431// in the latter two cases. 432// status: The exit status of the child process. On *nix, it is in the 433// in the format specified by wait(2). On Windows, this is the 434// value supplied to the ExitProcess() API or a numeric code 435// of the exception that terminated the program. 436// regex: A regular expression object to be applied to 437// the test's captured standard error output; the death test 438// fails if it does not match. 439// 440// Argument: 441// status_ok: true if exit_status is acceptable in the context of 442// this particular death test, which fails if it is false 443// 444// Returns true iff all of the above conditions are met. Otherwise, the 445// first failing condition, in the order given above, is the one that is 446// reported. Also sets the last death test message string. 447bool DeathTestImpl::Passed(bool status_ok) { 448 if (!spawned()) 449 return false; 450 451 const String error_message = GetCapturedStderr(); 452 453 bool success = false; 454 Message buffer; 455 456 buffer << "Death test: " << statement() << "\n"; 457 switch (outcome()) { 458 case LIVED: 459 buffer << " Result: failed to die.\n" 460 << " Error msg: " << error_message; 461 break; 462 case RETURNED: 463 buffer << " Result: illegal return in test statement.\n" 464 << " Error msg: " << error_message; 465 break; 466 case DIED: 467 if (status_ok) { 468 const bool matched = RE::PartialMatch(error_message.c_str(), *regex()); 469 if (matched) { 470 success = true; 471 } else { 472 buffer << " Result: died but not with expected error.\n" 473 << " Expected: " << regex()->pattern() << "\n" 474 << "Actual msg: " << error_message; 475 } 476 } else { 477 buffer << " Result: died but not with expected exit code:\n" 478 << " " << ExitSummary(status()) << "\n"; 479 } 480 break; 481 case IN_PROGRESS: 482 default: 483 GTEST_LOG_(FATAL) 484 << "DeathTest::Passed somehow called before conclusion of test"; 485 } 486 487 DeathTest::set_last_death_test_message(buffer.GetString()); 488 return success; 489} 490 491#if GTEST_OS_WINDOWS 492// WindowsDeathTest implements death tests on Windows. Due to the 493// specifics of starting new processes on Windows, death tests there are 494// always threadsafe, and Google Test considers the 495// --gtest_death_test_style=fast setting to be equivalent to 496// --gtest_death_test_style=threadsafe there. 497// 498// A few implementation notes: Like the Linux version, the Windows 499// implementation uses pipes for child-to-parent communication. But due to 500// the specifics of pipes on Windows, some extra steps are required: 501// 502// 1. The parent creates a communication pipe and stores handles to both 503// ends of it. 504// 2. The parent starts the child and provides it with the information 505// necessary to acquire the handle to the write end of the pipe. 506// 3. The child acquires the write end of the pipe and signals the parent 507// using a Windows event. 508// 4. Now the parent can release the write end of the pipe on its side. If 509// this is done before step 3, the object's reference count goes down to 510// 0 and it is destroyed, preventing the child from acquiring it. The 511// parent now has to release it, or read operations on the read end of 512// the pipe will not return when the child terminates. 513// 5. The parent reads child's output through the pipe (outcome code and 514// any possible error messages) from the pipe, and its stderr and then 515// determines whether to fail the test. 516// 517// Note: to distinguish Win32 API calls from the local method and function 518// calls, the former are explicitly resolved in the global namespace. 519// 520class WindowsDeathTest : public DeathTestImpl { 521 public: 522 WindowsDeathTest(const char* statement, 523 const RE* regex, 524 const char* file, 525 int line) 526 : DeathTestImpl(statement, regex), file_(file), line_(line) {} 527 528 // All of these virtual functions are inherited from DeathTest. 529 virtual int Wait(); 530 virtual TestRole AssumeRole(); 531 532 private: 533 // The name of the file in which the death test is located. 534 const char* const file_; 535 // The line number on which the death test is located. 536 const int line_; 537 // Handle to the write end of the pipe to the child process. 538 AutoHandle write_handle_; 539 // Child process handle. 540 AutoHandle child_handle_; 541 // Event the child process uses to signal the parent that it has 542 // acquired the handle to the write end of the pipe. After seeing this 543 // event the parent can release its own handles to make sure its 544 // ReadFile() calls return when the child terminates. 545 AutoHandle event_handle_; 546}; 547 548// Waits for the child in a death test to exit, returning its exit 549// status, or 0 if no child process exists. As a side effect, sets the 550// outcome data member. 551int WindowsDeathTest::Wait() { 552 if (!spawned()) 553 return 0; 554 555 // Wait until the child either signals that it has acquired the write end 556 // of the pipe or it dies. 557 const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() }; 558 switch (::WaitForMultipleObjects(2, 559 wait_handles, 560 FALSE, // Waits for any of the handles. 561 INFINITE)) { 562 case WAIT_OBJECT_0: 563 case WAIT_OBJECT_0 + 1: 564 break; 565 default: 566 GTEST_DEATH_TEST_CHECK_(false); // Should not get here. 567 } 568 569 // The child has acquired the write end of the pipe or exited. 570 // We release the handle on our side and continue. 571 write_handle_.Reset(); 572 event_handle_.Reset(); 573 574 ReadAndInterpretStatusByte(); 575 576 // Waits for the child process to exit if it haven't already. This 577 // returns immediately if the child has already exited, regardless of 578 // whether previous calls to WaitForMultipleObjects synchronized on this 579 // handle or not. 580 GTEST_DEATH_TEST_CHECK_( 581 WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(), 582 INFINITE)); 583 DWORD status; 584 GTEST_DEATH_TEST_CHECK_(::GetExitCodeProcess(child_handle_.Get(), &status) 585 != FALSE); 586 child_handle_.Reset(); 587 set_status(static_cast<int>(status)); 588 return this->status(); 589} 590 591// The AssumeRole process for a Windows death test. It creates a child 592// process with the same executable as the current process to run the 593// death test. The child process is given the --gtest_filter and 594// --gtest_internal_run_death_test flags such that it knows to run the 595// current death test only. 596DeathTest::TestRole WindowsDeathTest::AssumeRole() { 597 const UnitTestImpl* const impl = GetUnitTestImpl(); 598 const InternalRunDeathTestFlag* const flag = 599 impl->internal_run_death_test_flag(); 600 const TestInfo* const info = impl->current_test_info(); 601 const int death_test_index = info->result()->death_test_count(); 602 603 if (flag != NULL) { 604 // ParseInternalRunDeathTestFlag() has performed all the necessary 605 // processing. 606 set_write_fd(flag->write_fd()); 607 return EXECUTE_TEST; 608 } 609 610 // WindowsDeathTest uses an anonymous pipe to communicate results of 611 // a death test. 612 SECURITY_ATTRIBUTES handles_are_inheritable = { 613 sizeof(SECURITY_ATTRIBUTES), NULL, TRUE }; 614 HANDLE read_handle, write_handle; 615 GTEST_DEATH_TEST_CHECK_( 616 ::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable, 617 0) // Default buffer size. 618 != FALSE); 619 set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle), 620 O_RDONLY)); 621 write_handle_.Reset(write_handle); 622 event_handle_.Reset(::CreateEvent( 623 &handles_are_inheritable, 624 TRUE, // The event will automatically reset to non-signaled state. 625 FALSE, // The initial state is non-signalled. 626 NULL)); // The even is unnamed. 627 GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL); 628 const String filter_flag = String::Format("--%s%s=%s.%s", 629 GTEST_FLAG_PREFIX_, kFilterFlag, 630 info->test_case_name(), 631 info->name()); 632 const String internal_flag = String::Format( 633 "--%s%s=%s|%d|%d|%u|%Iu|%Iu", 634 GTEST_FLAG_PREFIX_, 635 kInternalRunDeathTestFlag, 636 file_, line_, 637 death_test_index, 638 static_cast<unsigned int>(::GetCurrentProcessId()), 639 // size_t has the same with as pointers on both 32-bit and 64-bit 640 // Windows platforms. 641 // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx. 642 reinterpret_cast<size_t>(write_handle), 643 reinterpret_cast<size_t>(event_handle_.Get())); 644 645 char executable_path[_MAX_PATH + 1]; // NOLINT 646 GTEST_DEATH_TEST_CHECK_( 647 _MAX_PATH + 1 != ::GetModuleFileNameA(NULL, 648 executable_path, 649 _MAX_PATH)); 650 651 String command_line = String::Format("%s %s \"%s\"", 652 ::GetCommandLineA(), 653 filter_flag.c_str(), 654 internal_flag.c_str()); 655 656 DeathTest::set_last_death_test_message(""); 657 658 CaptureStderr(); 659 // Flush the log buffers since the log streams are shared with the child. 660 FlushInfoLog(); 661 662 // The child process will share the standard handles with the parent. 663 STARTUPINFOA startup_info; 664 memset(&startup_info, 0, sizeof(STARTUPINFO)); 665 startup_info.dwFlags = STARTF_USESTDHANDLES; 666 startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE); 667 startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE); 668 startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE); 669 670 PROCESS_INFORMATION process_info; 671 GTEST_DEATH_TEST_CHECK_(::CreateProcessA( 672 executable_path, 673 const_cast<char*>(command_line.c_str()), 674 NULL, // Retuned process handle is not inheritable. 675 NULL, // Retuned thread handle is not inheritable. 676 TRUE, // Child inherits all inheritable handles (for write_handle_). 677 0x0, // Default creation flags. 678 NULL, // Inherit the parent's environment. 679 UnitTest::GetInstance()->original_working_dir(), 680 &startup_info, 681 &process_info) != FALSE); 682 child_handle_.Reset(process_info.hProcess); 683 ::CloseHandle(process_info.hThread); 684 set_spawned(true); 685 return OVERSEE_TEST; 686} 687#else // We are not on Windows. 688 689// ForkingDeathTest provides implementations for most of the abstract 690// methods of the DeathTest interface. Only the AssumeRole method is 691// left undefined. 692class ForkingDeathTest : public DeathTestImpl { 693 public: 694 ForkingDeathTest(const char* statement, const RE* regex); 695 696 // All of these virtual functions are inherited from DeathTest. 697 virtual int Wait(); 698 699 protected: 700 void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; } 701 702 private: 703 // PID of child process during death test; 0 in the child process itself. 704 pid_t child_pid_; 705}; 706 707// Constructs a ForkingDeathTest. 708ForkingDeathTest::ForkingDeathTest(const char* statement, const RE* regex) 709 : DeathTestImpl(statement, regex), 710 child_pid_(-1) {} 711 712// Waits for the child in a death test to exit, returning its exit 713// status, or 0 if no child process exists. As a side effect, sets the 714// outcome data member. 715int ForkingDeathTest::Wait() { 716 if (!spawned()) 717 return 0; 718 719 ReadAndInterpretStatusByte(); 720 721 int status; 722 GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status, 0)); 723 set_status(status); 724 return status; 725} 726 727// A concrete death test class that forks, then immediately runs the test 728// in the child process. 729class NoExecDeathTest : public ForkingDeathTest { 730 public: 731 NoExecDeathTest(const char* statement, const RE* regex) : 732 ForkingDeathTest(statement, regex) { } 733 virtual TestRole AssumeRole(); 734}; 735 736// The AssumeRole process for a fork-and-run death test. It implements a 737// straightforward fork, with a simple pipe to transmit the status byte. 738DeathTest::TestRole NoExecDeathTest::AssumeRole() { 739 const size_t thread_count = GetThreadCount(); 740 if (thread_count != 1) { 741 GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count); 742 } 743 744 int pipe_fd[2]; 745 GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1); 746 747 DeathTest::set_last_death_test_message(""); 748 CaptureStderr(); 749 // When we fork the process below, the log file buffers are copied, but the 750 // file descriptors are shared. We flush all log files here so that closing 751 // the file descriptors in the child process doesn't throw off the 752 // synchronization between descriptors and buffers in the parent process. 753 // This is as close to the fork as possible to avoid a race condition in case 754 // there are multiple threads running before the death test, and another 755 // thread writes to the log file. 756 FlushInfoLog(); 757 758 const pid_t child_pid = fork(); 759 GTEST_DEATH_TEST_CHECK_(child_pid != -1); 760 set_child_pid(child_pid); 761 if (child_pid == 0) { 762 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0])); 763 set_write_fd(pipe_fd[1]); 764 // Redirects all logging to stderr in the child process to prevent 765 // concurrent writes to the log files. We capture stderr in the parent 766 // process and append the child process' output to a log. 767 LogToStderr(); 768 // Event forwarding to the listeners of event listener API mush be shut 769 // down in death test subprocesses. 770 GetUnitTestImpl()->listeners()->SuppressEventForwarding(); 771 return EXECUTE_TEST; 772 } else { 773 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1])); 774 set_read_fd(pipe_fd[0]); 775 set_spawned(true); 776 return OVERSEE_TEST; 777 } 778} 779 780// A concrete death test class that forks and re-executes the main 781// program from the beginning, with command-line flags set that cause 782// only this specific death test to be run. 783class ExecDeathTest : public ForkingDeathTest { 784 public: 785 ExecDeathTest(const char* statement, const RE* regex, 786 const char* file, int line) : 787 ForkingDeathTest(statement, regex), file_(file), line_(line) { } 788 virtual TestRole AssumeRole(); 789 private: 790 // The name of the file in which the death test is located. 791 const char* const file_; 792 // The line number on which the death test is located. 793 const int line_; 794}; 795 796// Utility class for accumulating command-line arguments. 797class Arguments { 798 public: 799 Arguments() { 800 args_.push_back(NULL); 801 } 802 803 ~Arguments() { 804 for (std::vector<char*>::iterator i = args_.begin(); i != args_.end(); 805 ++i) { 806 free(*i); 807 } 808 } 809 void AddArgument(const char* argument) { 810 args_.insert(args_.end() - 1, posix::StrDup(argument)); 811 } 812 813 template <typename Str> 814 void AddArguments(const ::std::vector<Str>& arguments) { 815 for (typename ::std::vector<Str>::const_iterator i = arguments.begin(); 816 i != arguments.end(); 817 ++i) { 818 args_.insert(args_.end() - 1, posix::StrDup(i->c_str())); 819 } 820 } 821 char* const* Argv() { 822 return &args_[0]; 823 } 824 private: 825 std::vector<char*> args_; 826}; 827 828// A struct that encompasses the arguments to the child process of a 829// threadsafe-style death test process. 830struct ExecDeathTestArgs { 831 char* const* argv; // Command-line arguments for the child's call to exec 832 int close_fd; // File descriptor to close; the read end of a pipe 833}; 834 835#if GTEST_OS_MAC 836inline char** GetEnviron() { 837 // When Google Test is built as a framework on MacOS X, the environ variable 838 // is unavailable. Apple's documentation (man environ) recommends using 839 // _NSGetEnviron() instead. 840 return *_NSGetEnviron(); 841} 842#else 843// Some POSIX platforms expect you to declare environ. extern "C" makes 844// it reside in the global namespace. 845extern "C" char** environ; 846inline char** GetEnviron() { return environ; } 847#endif // GTEST_OS_MAC 848 849// The main function for a threadsafe-style death test child process. 850// This function is called in a clone()-ed process and thus must avoid 851// any potentially unsafe operations like malloc or libc functions. 852static int ExecDeathTestChildMain(void* child_arg) { 853 ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg); 854 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd)); 855 856 // We need to execute the test program in the same environment where 857 // it was originally invoked. Therefore we change to the original 858 // working directory first. 859 const char* const original_dir = 860 UnitTest::GetInstance()->original_working_dir(); 861 // We can safely call chdir() as it's a direct system call. 862 if (chdir(original_dir) != 0) { 863 DeathTestAbort(String::Format("chdir(\"%s\") failed: %s", 864 original_dir, 865 GetLastErrnoDescription().c_str())); 866 return EXIT_FAILURE; 867 } 868 869 // We can safely call execve() as it's a direct system call. We 870 // cannot use execvp() as it's a libc function and thus potentially 871 // unsafe. Since execve() doesn't search the PATH, the user must 872 // invoke the test program via a valid path that contains at least 873 // one path separator. 874 execve(args->argv[0], args->argv, GetEnviron()); 875 DeathTestAbort(String::Format("execve(%s, ...) in %s failed: %s", 876 args->argv[0], 877 original_dir, 878 GetLastErrnoDescription().c_str())); 879 return EXIT_FAILURE; 880} 881 882// Two utility routines that together determine the direction the stack 883// grows. 884// This could be accomplished more elegantly by a single recursive 885// function, but we want to guard against the unlikely possibility of 886// a smart compiler optimizing the recursion away. 887bool StackLowerThanAddress(const void* ptr) { 888 int dummy; 889 return &dummy < ptr; 890} 891 892bool StackGrowsDown() { 893 int dummy; 894 return StackLowerThanAddress(&dummy); 895} 896 897// A threadsafe implementation of fork(2) for threadsafe-style death tests 898// that uses clone(2). It dies with an error message if anything goes 899// wrong. 900static pid_t ExecDeathTestFork(char* const* argv, int close_fd) { 901 ExecDeathTestArgs args = { argv, close_fd }; 902 pid_t child_pid = -1; 903 904#if GTEST_HAS_CLONE 905 const bool use_fork = GTEST_FLAG(death_test_use_fork); 906 907 if (!use_fork) { 908 static const bool stack_grows_down = StackGrowsDown(); 909 const size_t stack_size = getpagesize(); 910 // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead. 911 void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, 912 MAP_ANON | MAP_PRIVATE, -1, 0); 913 GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED); 914 void* const stack_top = 915 static_cast<char*>(stack) + (stack_grows_down ? stack_size : 0); 916 917 child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args); 918 919 GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1); 920 } 921#else 922 const bool use_fork = true; 923#endif // GTEST_HAS_CLONE 924 925 if (use_fork && (child_pid = fork()) == 0) { 926 ExecDeathTestChildMain(&args); 927 _exit(0); 928 } 929 930 GTEST_DEATH_TEST_CHECK_(child_pid != -1); 931 return child_pid; 932} 933 934// The AssumeRole process for a fork-and-exec death test. It re-executes the 935// main program from the beginning, setting the --gtest_filter 936// and --gtest_internal_run_death_test flags to cause only the current 937// death test to be re-run. 938DeathTest::TestRole ExecDeathTest::AssumeRole() { 939 const UnitTestImpl* const impl = GetUnitTestImpl(); 940 const InternalRunDeathTestFlag* const flag = 941 impl->internal_run_death_test_flag(); 942 const TestInfo* const info = impl->current_test_info(); 943 const int death_test_index = info->result()->death_test_count(); 944 945 if (flag != NULL) { 946 set_write_fd(flag->write_fd()); 947 return EXECUTE_TEST; 948 } 949 950 int pipe_fd[2]; 951 GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1); 952 // Clear the close-on-exec flag on the write end of the pipe, lest 953 // it be closed when the child process does an exec: 954 GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1); 955 956 const String filter_flag = 957 String::Format("--%s%s=%s.%s", 958 GTEST_FLAG_PREFIX_, kFilterFlag, 959 info->test_case_name(), info->name()); 960 const String internal_flag = 961 String::Format("--%s%s=%s|%d|%d|%d", 962 GTEST_FLAG_PREFIX_, kInternalRunDeathTestFlag, 963 file_, line_, death_test_index, pipe_fd[1]); 964 Arguments args; 965 args.AddArguments(GetArgvs()); 966 args.AddArgument(filter_flag.c_str()); 967 args.AddArgument(internal_flag.c_str()); 968 969 DeathTest::set_last_death_test_message(""); 970 971 CaptureStderr(); 972 // See the comment in NoExecDeathTest::AssumeRole for why the next line 973 // is necessary. 974 FlushInfoLog(); 975 976 const pid_t child_pid = ExecDeathTestFork(args.Argv(), pipe_fd[0]); 977 GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1])); 978 set_child_pid(child_pid); 979 set_read_fd(pipe_fd[0]); 980 set_spawned(true); 981 return OVERSEE_TEST; 982} 983 984#endif // !GTEST_OS_WINDOWS 985 986// Creates a concrete DeathTest-derived class that depends on the 987// --gtest_death_test_style flag, and sets the pointer pointed to 988// by the "test" argument to its address. If the test should be 989// skipped, sets that pointer to NULL. Returns true, unless the 990// flag is set to an invalid value. 991bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex, 992 const char* file, int line, 993 DeathTest** test) { 994 UnitTestImpl* const impl = GetUnitTestImpl(); 995 const InternalRunDeathTestFlag* const flag = 996 impl->internal_run_death_test_flag(); 997 const int death_test_index = impl->current_test_info() 998 ->increment_death_test_count(); 999 1000 if (flag != NULL) { 1001 if (death_test_index > flag->index()) { 1002 DeathTest::set_last_death_test_message(String::Format( 1003 "Death test count (%d) somehow exceeded expected maximum (%d)", 1004 death_test_index, flag->index())); 1005 return false; 1006 } 1007 1008 if (!(flag->file() == file && flag->line() == line && 1009 flag->index() == death_test_index)) { 1010 *test = NULL; 1011 return true; 1012 } 1013 } 1014 1015#if GTEST_OS_WINDOWS 1016 if (GTEST_FLAG(death_test_style) == "threadsafe" || 1017 GTEST_FLAG(death_test_style) == "fast") { 1018 *test = new WindowsDeathTest(statement, regex, file, line); 1019 } 1020#else 1021 if (GTEST_FLAG(death_test_style) == "threadsafe") { 1022 *test = new ExecDeathTest(statement, regex, file, line); 1023 } else if (GTEST_FLAG(death_test_style) == "fast") { 1024 *test = new NoExecDeathTest(statement, regex); 1025 } 1026#endif // GTEST_OS_WINDOWS 1027 else { // NOLINT - this is more readable than unbalanced brackets inside #if. 1028 DeathTest::set_last_death_test_message(String::Format( 1029 "Unknown death test style \"%s\" encountered", 1030 GTEST_FLAG(death_test_style).c_str())); 1031 return false; 1032 } 1033 1034 return true; 1035} 1036 1037// Splits a given string on a given delimiter, populating a given 1038// vector with the fields. GTEST_HAS_DEATH_TEST implies that we have 1039// ::std::string, so we can use it here. 1040// TODO(vladl@google.com): Get rid of std::vector to be able to build on 1041// Visual C++ 7.1 with exceptions disabled. 1042static void SplitString(const ::std::string& str, char delimiter, 1043 ::std::vector< ::std::string>* dest) { 1044 ::std::vector< ::std::string> parsed; 1045 ::std::string::size_type pos = 0; 1046 while (::testing::internal::AlwaysTrue()) { 1047 const ::std::string::size_type colon = str.find(delimiter, pos); 1048 if (colon == ::std::string::npos) { 1049 parsed.push_back(str.substr(pos)); 1050 break; 1051 } else { 1052 parsed.push_back(str.substr(pos, colon - pos)); 1053 pos = colon + 1; 1054 } 1055 } 1056 dest->swap(parsed); 1057} 1058 1059#if GTEST_OS_WINDOWS 1060// Recreates the pipe and event handles from the provided parameters, 1061// signals the event, and returns a file descriptor wrapped around the pipe 1062// handle. This function is called in the child process only. 1063int GetStatusFileDescriptor(unsigned int parent_process_id, 1064 size_t write_handle_as_size_t, 1065 size_t event_handle_as_size_t) { 1066 AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE, 1067 FALSE, // Non-inheritable. 1068 parent_process_id)); 1069 if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) { 1070 DeathTestAbort(String::Format("Unable to open parent process %u", 1071 parent_process_id)); 1072 } 1073 1074 // TODO(vladl@google.com): Replace the following check with a 1075 // compile-time assertion when available. 1076 GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t)); 1077 1078 const HANDLE write_handle = 1079 reinterpret_cast<HANDLE>(write_handle_as_size_t); 1080 HANDLE dup_write_handle; 1081 1082 // The newly initialized handle is accessible only in in the parent 1083 // process. To obtain one accessible within the child, we need to use 1084 // DuplicateHandle. 1085 if (!::DuplicateHandle(parent_process_handle.Get(), write_handle, 1086 ::GetCurrentProcess(), &dup_write_handle, 1087 0x0, // Requested privileges ignored since 1088 // DUPLICATE_SAME_ACCESS is used. 1089 FALSE, // Request non-inheritable handler. 1090 DUPLICATE_SAME_ACCESS)) { 1091 DeathTestAbort(String::Format( 1092 "Unable to duplicate the pipe handle %Iu from the parent process %u", 1093 write_handle_as_size_t, parent_process_id)); 1094 } 1095 1096 const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t); 1097 HANDLE dup_event_handle; 1098 1099 if (!::DuplicateHandle(parent_process_handle.Get(), event_handle, 1100 ::GetCurrentProcess(), &dup_event_handle, 1101 0x0, 1102 FALSE, 1103 DUPLICATE_SAME_ACCESS)) { 1104 DeathTestAbort(String::Format( 1105 "Unable to duplicate the event handle %Iu from the parent process %u", 1106 event_handle_as_size_t, parent_process_id)); 1107 } 1108 1109 const int write_fd = 1110 ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND); 1111 if (write_fd == -1) { 1112 DeathTestAbort(String::Format( 1113 "Unable to convert pipe handle %Iu to a file descriptor", 1114 write_handle_as_size_t)); 1115 } 1116 1117 // Signals the parent that the write end of the pipe has been acquired 1118 // so the parent can release its own write end. 1119 ::SetEvent(dup_event_handle); 1120 1121 return write_fd; 1122} 1123#endif // GTEST_OS_WINDOWS 1124 1125// Returns a newly created InternalRunDeathTestFlag object with fields 1126// initialized from the GTEST_FLAG(internal_run_death_test) flag if 1127// the flag is specified; otherwise returns NULL. 1128InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() { 1129 if (GTEST_FLAG(internal_run_death_test) == "") return NULL; 1130 1131 // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we 1132 // can use it here. 1133 int line = -1; 1134 int index = -1; 1135 ::std::vector< ::std::string> fields; 1136 SplitString(GTEST_FLAG(internal_run_death_test).c_str(), '|', &fields); 1137 int write_fd = -1; 1138 1139#if GTEST_OS_WINDOWS 1140 unsigned int parent_process_id = 0; 1141 size_t write_handle_as_size_t = 0; 1142 size_t event_handle_as_size_t = 0; 1143 1144 if (fields.size() != 6 1145 || !ParseNaturalNumber(fields[1], &line) 1146 || !ParseNaturalNumber(fields[2], &index) 1147 || !ParseNaturalNumber(fields[3], &parent_process_id) 1148 || !ParseNaturalNumber(fields[4], &write_handle_as_size_t) 1149 || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) { 1150 DeathTestAbort(String::Format( 1151 "Bad --gtest_internal_run_death_test flag: %s", 1152 GTEST_FLAG(internal_run_death_test).c_str())); 1153 } 1154 write_fd = GetStatusFileDescriptor(parent_process_id, 1155 write_handle_as_size_t, 1156 event_handle_as_size_t); 1157#else 1158 if (fields.size() != 4 1159 || !ParseNaturalNumber(fields[1], &line) 1160 || !ParseNaturalNumber(fields[2], &index) 1161 || !ParseNaturalNumber(fields[3], &write_fd)) { 1162 DeathTestAbort(String::Format( 1163 "Bad --gtest_internal_run_death_test flag: %s", 1164 GTEST_FLAG(internal_run_death_test).c_str())); 1165 } 1166#endif // GTEST_OS_WINDOWS 1167 return new InternalRunDeathTestFlag(fields[0], line, index, write_fd); 1168} 1169 1170} // namespace internal 1171 1172#endif // GTEST_HAS_DEATH_TEST 1173 1174} // namespace testing