michael@0: // Copyright 2005, Google Inc.
michael@0: // All rights reserved.
michael@0: //
michael@0: // Redistribution and use in source and binary forms, with or without
michael@0: // modification, are permitted provided that the following conditions are
michael@0: // met:
michael@0: //
michael@0: //     * Redistributions of source code must retain the above copyright
michael@0: // notice, this list of conditions and the following disclaimer.
michael@0: //     * Redistributions in binary form must reproduce the above
michael@0: // copyright notice, this list of conditions and the following disclaimer
michael@0: // in the documentation and/or other materials provided with the
michael@0: // distribution.
michael@0: //     * Neither the name of Google Inc. nor the names of its
michael@0: // contributors may be used to endorse or promote products derived from
michael@0: // this software without specific prior written permission.
michael@0: //
michael@0: // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
michael@0: // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
michael@0: // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: //
michael@0: // Author: wan@google.com (Zhanyong Wan), vladl@google.com (Vlad Losev)
michael@0: //
michael@0: // This file implements death tests.
michael@0: 
michael@0: #include "gtest/gtest-death-test.h"
michael@0: #include "gtest/internal/gtest-port.h"
michael@0: 
michael@0: #if GTEST_HAS_DEATH_TEST
michael@0: 
michael@0: # if GTEST_OS_MAC
michael@0: #  include <crt_externs.h>
michael@0: # endif  // GTEST_OS_MAC
michael@0: 
michael@0: # include <errno.h>
michael@0: # include <fcntl.h>
michael@0: # include <limits.h>
michael@0: 
michael@0: # if GTEST_OS_LINUX
michael@0: #  include <signal.h>
michael@0: # endif  // GTEST_OS_LINUX
michael@0: 
michael@0: # include <stdarg.h>
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: #  include <windows.h>
michael@0: # else
michael@0: #  include <sys/mman.h>
michael@0: #  include <sys/wait.h>
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: 
michael@0: # if GTEST_OS_QNX
michael@0: #  include <spawn.h>
michael@0: # endif  // GTEST_OS_QNX
michael@0: 
michael@0: #endif  // GTEST_HAS_DEATH_TEST
michael@0: 
michael@0: #include "gtest/gtest-message.h"
michael@0: #include "gtest/internal/gtest-string.h"
michael@0: 
michael@0: // Indicates that this translation unit is part of Google Test's
michael@0: // implementation.  It must come before gtest-internal-inl.h is
michael@0: // included, or there will be a compiler error.  This trick is to
michael@0: // prevent a user from accidentally including gtest-internal-inl.h in
michael@0: // his code.
michael@0: #define GTEST_IMPLEMENTATION_ 1
michael@0: #include "src/gtest-internal-inl.h"
michael@0: #undef GTEST_IMPLEMENTATION_
michael@0: 
michael@0: namespace testing {
michael@0: 
michael@0: // Constants.
michael@0: 
michael@0: // The default death test style.
michael@0: static const char kDefaultDeathTestStyle[] = "fast";
michael@0: 
michael@0: GTEST_DEFINE_string_(
michael@0:     death_test_style,
michael@0:     internal::StringFromGTestEnv("death_test_style", kDefaultDeathTestStyle),
michael@0:     "Indicates how to run a death test in a forked child process: "
michael@0:     "\"threadsafe\" (child process re-executes the test binary "
michael@0:     "from the beginning, running only the specific death test) or "
michael@0:     "\"fast\" (child process runs the death test immediately "
michael@0:     "after forking).");
michael@0: 
michael@0: GTEST_DEFINE_bool_(
michael@0:     death_test_use_fork,
michael@0:     internal::BoolFromGTestEnv("death_test_use_fork", false),
michael@0:     "Instructs to use fork()/_exit() instead of clone() in death tests. "
michael@0:     "Ignored and always uses fork() on POSIX systems where clone() is not "
michael@0:     "implemented. Useful when running under valgrind or similar tools if "
michael@0:     "those do not support clone(). Valgrind 3.3.1 will just fail if "
michael@0:     "it sees an unsupported combination of clone() flags. "
michael@0:     "It is not recommended to use this flag w/o valgrind though it will "
michael@0:     "work in 99% of the cases. Once valgrind is fixed, this flag will "
michael@0:     "most likely be removed.");
michael@0: 
michael@0: namespace internal {
michael@0: GTEST_DEFINE_string_(
michael@0:     internal_run_death_test, "",
michael@0:     "Indicates the file, line number, temporal index of "
michael@0:     "the single death test to run, and a file descriptor to "
michael@0:     "which a success code may be sent, all separated by "
michael@0:     "the '|' characters.  This flag is specified if and only if the current "
michael@0:     "process is a sub-process launched for running a thread-safe "
michael@0:     "death test.  FOR INTERNAL USE ONLY.");
michael@0: }  // namespace internal
michael@0: 
michael@0: #if GTEST_HAS_DEATH_TEST
michael@0: 
michael@0: namespace internal {
michael@0: 
michael@0: // Valid only for fast death tests. Indicates the code is running in the
michael@0: // child process of a fast style death test.
michael@0: static bool g_in_fast_death_test_child = false;
michael@0: 
michael@0: // Returns a Boolean value indicating whether the caller is currently
michael@0: // executing in the context of the death test child process.  Tools such as
michael@0: // Valgrind heap checkers may need this to modify their behavior in death
michael@0: // tests.  IMPORTANT: This is an internal utility.  Using it may break the
michael@0: // implementation of death tests.  User code MUST NOT use it.
michael@0: bool InDeathTestChild() {
michael@0: # if GTEST_OS_WINDOWS
michael@0: 
michael@0:   // On Windows, death tests are thread-safe regardless of the value of the
michael@0:   // death_test_style flag.
michael@0:   return !GTEST_FLAG(internal_run_death_test).empty();
michael@0: 
michael@0: # else
michael@0: 
michael@0:   if (GTEST_FLAG(death_test_style) == "threadsafe")
michael@0:     return !GTEST_FLAG(internal_run_death_test).empty();
michael@0:   else
michael@0:     return g_in_fast_death_test_child;
michael@0: #endif
michael@0: }
michael@0: 
michael@0: }  // namespace internal
michael@0: 
michael@0: // ExitedWithCode constructor.
michael@0: ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
michael@0: }
michael@0: 
michael@0: // ExitedWithCode function-call operator.
michael@0: bool ExitedWithCode::operator()(int exit_status) const {
michael@0: # if GTEST_OS_WINDOWS
michael@0: 
michael@0:   return exit_status == exit_code_;
michael@0: 
michael@0: # else
michael@0: 
michael@0:   return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;
michael@0: 
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: }
michael@0: 
michael@0: # if !GTEST_OS_WINDOWS
michael@0: // KilledBySignal constructor.
michael@0: KilledBySignal::KilledBySignal(int signum) : signum_(signum) {
michael@0: }
michael@0: 
michael@0: // KilledBySignal function-call operator.
michael@0: bool KilledBySignal::operator()(int exit_status) const {
michael@0:   return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;
michael@0: }
michael@0: # endif  // !GTEST_OS_WINDOWS
michael@0: 
michael@0: namespace internal {
michael@0: 
michael@0: // Utilities needed for death tests.
michael@0: 
michael@0: // Generates a textual description of a given exit code, in the format
michael@0: // specified by wait(2).
michael@0: static String ExitSummary(int exit_code) {
michael@0:   Message m;
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: 
michael@0:   m << "Exited with exit status " << exit_code;
michael@0: 
michael@0: # else
michael@0: 
michael@0:   if (WIFEXITED(exit_code)) {
michael@0:     m << "Exited with exit status " << WEXITSTATUS(exit_code);
michael@0:   } else if (WIFSIGNALED(exit_code)) {
michael@0:     m << "Terminated by signal " << WTERMSIG(exit_code);
michael@0:   }
michael@0: #  ifdef WCOREDUMP
michael@0:   if (WCOREDUMP(exit_code)) {
michael@0:     m << " (core dumped)";
michael@0:   }
michael@0: #  endif
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: 
michael@0:   return m.GetString();
michael@0: }
michael@0: 
michael@0: // Returns true if exit_status describes a process that was terminated
michael@0: // by a signal, or exited normally with a nonzero exit code.
michael@0: bool ExitedUnsuccessfully(int exit_status) {
michael@0:   return !ExitedWithCode(0)(exit_status);
michael@0: }
michael@0: 
michael@0: # if !GTEST_OS_WINDOWS
michael@0: // Generates a textual failure message when a death test finds more than
michael@0: // one thread running, or cannot determine the number of threads, prior
michael@0: // to executing the given statement.  It is the responsibility of the
michael@0: // caller not to pass a thread_count of 1.
michael@0: static String DeathTestThreadWarning(size_t thread_count) {
michael@0:   Message msg;
michael@0:   msg << "Death tests use fork(), which is unsafe particularly"
michael@0:       << " in a threaded context. For this test, " << GTEST_NAME_ << " ";
michael@0:   if (thread_count == 0)
michael@0:     msg << "couldn't detect the number of threads.";
michael@0:   else
michael@0:     msg << "detected " << thread_count << " threads.";
michael@0:   return msg.GetString();
michael@0: }
michael@0: # endif  // !GTEST_OS_WINDOWS
michael@0: 
michael@0: // Flag characters for reporting a death test that did not die.
michael@0: static const char kDeathTestLived = 'L';
michael@0: static const char kDeathTestReturned = 'R';
michael@0: static const char kDeathTestThrew = 'T';
michael@0: static const char kDeathTestInternalError = 'I';
michael@0: 
michael@0: // An enumeration describing all of the possible ways that a death test can
michael@0: // conclude.  DIED means that the process died while executing the test
michael@0: // code; LIVED means that process lived beyond the end of the test code;
michael@0: // RETURNED means that the test statement attempted to execute a return
michael@0: // statement, which is not allowed; THREW means that the test statement
michael@0: // returned control by throwing an exception.  IN_PROGRESS means the test
michael@0: // has not yet concluded.
michael@0: // TODO(vladl@google.com): Unify names and possibly values for
michael@0: // AbortReason, DeathTestOutcome, and flag characters above.
michael@0: enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED, THREW };
michael@0: 
michael@0: // Routine for aborting the program which is safe to call from an
michael@0: // exec-style death test child process, in which case the error
michael@0: // message is propagated back to the parent process.  Otherwise, the
michael@0: // message is simply printed to stderr.  In either case, the program
michael@0: // then exits with status 1.
michael@0: void DeathTestAbort(const String& message) {
michael@0:   // On a POSIX system, this function may be called from a threadsafe-style
michael@0:   // death test child process, which operates on a very small stack.  Use
michael@0:   // the heap for any additional non-minuscule memory requirements.
michael@0:   const InternalRunDeathTestFlag* const flag =
michael@0:       GetUnitTestImpl()->internal_run_death_test_flag();
michael@0:   if (flag != NULL) {
michael@0:     FILE* parent = posix::FDOpen(flag->write_fd(), "w");
michael@0:     fputc(kDeathTestInternalError, parent);
michael@0:     fprintf(parent, "%s", message.c_str());
michael@0:     fflush(parent);
michael@0:     _exit(1);
michael@0:   } else {
michael@0:     fprintf(stderr, "%s", message.c_str());
michael@0:     fflush(stderr);
michael@0:     posix::Abort();
michael@0:   }
michael@0: }
michael@0: 
michael@0: // A replacement for CHECK that calls DeathTestAbort if the assertion
michael@0: // fails.
michael@0: # define GTEST_DEATH_TEST_CHECK_(expression) \
michael@0:   do { \
michael@0:     if (!::testing::internal::IsTrue(expression)) { \
michael@0:       DeathTestAbort(::testing::internal::String::Format( \
michael@0:           "CHECK failed: File %s, line %d: %s", \
michael@0:           __FILE__, __LINE__, #expression)); \
michael@0:     } \
michael@0:   } while (::testing::internal::AlwaysFalse())
michael@0: 
michael@0: // This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
michael@0: // evaluating any system call that fulfills two conditions: it must return
michael@0: // -1 on failure, and set errno to EINTR when it is interrupted and
michael@0: // should be tried again.  The macro expands to a loop that repeatedly
michael@0: // evaluates the expression as long as it evaluates to -1 and sets
michael@0: // errno to EINTR.  If the expression evaluates to -1 but errno is
michael@0: // something other than EINTR, DeathTestAbort is called.
michael@0: # define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \
michael@0:   do { \
michael@0:     int gtest_retval; \
michael@0:     do { \
michael@0:       gtest_retval = (expression); \
michael@0:     } while (gtest_retval == -1 && errno == EINTR); \
michael@0:     if (gtest_retval == -1) { \
michael@0:       DeathTestAbort(::testing::internal::String::Format( \
michael@0:           "CHECK failed: File %s, line %d: %s != -1", \
michael@0:           __FILE__, __LINE__, #expression)); \
michael@0:     } \
michael@0:   } while (::testing::internal::AlwaysFalse())
michael@0: 
michael@0: // Returns the message describing the last system error in errno.
michael@0: String GetLastErrnoDescription() {
michael@0:     return String(errno == 0 ? "" : posix::StrError(errno));
michael@0: }
michael@0: 
michael@0: // This is called from a death test parent process to read a failure
michael@0: // message from the death test child process and log it with the FATAL
michael@0: // severity. On Windows, the message is read from a pipe handle. On other
michael@0: // platforms, it is read from a file descriptor.
michael@0: static void FailFromInternalError(int fd) {
michael@0:   Message error;
michael@0:   char buffer[256];
michael@0:   int num_read;
michael@0: 
michael@0:   do {
michael@0:     while ((num_read = posix::Read(fd, buffer, 255)) > 0) {
michael@0:       buffer[num_read] = '\0';
michael@0:       error << buffer;
michael@0:     }
michael@0:   } while (num_read == -1 && errno == EINTR);
michael@0: 
michael@0:   if (num_read == 0) {
michael@0:     GTEST_LOG_(FATAL) << error.GetString();
michael@0:   } else {
michael@0:     const int last_error = errno;
michael@0:     GTEST_LOG_(FATAL) << "Error while reading death test internal: "
michael@0:                       << GetLastErrnoDescription() << " [" << last_error << "]";
michael@0:   }
michael@0: }
michael@0: 
michael@0: // Death test constructor.  Increments the running death test count
michael@0: // for the current test.
michael@0: DeathTest::DeathTest() {
michael@0:   TestInfo* const info = GetUnitTestImpl()->current_test_info();
michael@0:   if (info == NULL) {
michael@0:     DeathTestAbort("Cannot run a death test outside of a TEST or "
michael@0:                    "TEST_F construct");
michael@0:   }
michael@0: }
michael@0: 
michael@0: // Creates and returns a death test by dispatching to the current
michael@0: // death test factory.
michael@0: bool DeathTest::Create(const char* statement, const RE* regex,
michael@0:                        const char* file, int line, DeathTest** test) {
michael@0:   return GetUnitTestImpl()->death_test_factory()->Create(
michael@0:       statement, regex, file, line, test);
michael@0: }
michael@0: 
michael@0: const char* DeathTest::LastMessage() {
michael@0:   return last_death_test_message_.c_str();
michael@0: }
michael@0: 
michael@0: void DeathTest::set_last_death_test_message(const String& message) {
michael@0:   last_death_test_message_ = message;
michael@0: }
michael@0: 
michael@0: String DeathTest::last_death_test_message_;
michael@0: 
michael@0: // Provides cross platform implementation for some death functionality.
michael@0: class DeathTestImpl : public DeathTest {
michael@0:  protected:
michael@0:   DeathTestImpl(const char* a_statement, const RE* a_regex)
michael@0:       : statement_(a_statement),
michael@0:         regex_(a_regex),
michael@0:         spawned_(false),
michael@0:         status_(-1),
michael@0:         outcome_(IN_PROGRESS),
michael@0:         read_fd_(-1),
michael@0:         write_fd_(-1) {}
michael@0: 
michael@0:   // read_fd_ is expected to be closed and cleared by a derived class.
michael@0:   ~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }
michael@0: 
michael@0:   void Abort(AbortReason reason);
michael@0:   virtual bool Passed(bool status_ok);
michael@0: 
michael@0:   const char* statement() const { return statement_; }
michael@0:   const RE* regex() const { return regex_; }
michael@0:   bool spawned() const { return spawned_; }
michael@0:   void set_spawned(bool is_spawned) { spawned_ = is_spawned; }
michael@0:   int status() const { return status_; }
michael@0:   void set_status(int a_status) { status_ = a_status; }
michael@0:   DeathTestOutcome outcome() const { return outcome_; }
michael@0:   void set_outcome(DeathTestOutcome an_outcome) { outcome_ = an_outcome; }
michael@0:   int read_fd() const { return read_fd_; }
michael@0:   void set_read_fd(int fd) { read_fd_ = fd; }
michael@0:   int write_fd() const { return write_fd_; }
michael@0:   void set_write_fd(int fd) { write_fd_ = fd; }
michael@0: 
michael@0:   // Called in the parent process only. Reads the result code of the death
michael@0:   // test child process via a pipe, interprets it to set the outcome_
michael@0:   // member, and closes read_fd_.  Outputs diagnostics and terminates in
michael@0:   // case of unexpected codes.
michael@0:   void ReadAndInterpretStatusByte();
michael@0: 
michael@0:  private:
michael@0:   // The textual content of the code this object is testing.  This class
michael@0:   // doesn't own this string and should not attempt to delete it.
michael@0:   const char* const statement_;
michael@0:   // The regular expression which test output must match.  DeathTestImpl
michael@0:   // doesn't own this object and should not attempt to delete it.
michael@0:   const RE* const regex_;
michael@0:   // True if the death test child process has been successfully spawned.
michael@0:   bool spawned_;
michael@0:   // The exit status of the child process.
michael@0:   int status_;
michael@0:   // How the death test concluded.
michael@0:   DeathTestOutcome outcome_;
michael@0:   // Descriptor to the read end of the pipe to the child process.  It is
michael@0:   // always -1 in the child process.  The child keeps its write end of the
michael@0:   // pipe in write_fd_.
michael@0:   int read_fd_;
michael@0:   // Descriptor to the child's write end of the pipe to the parent process.
michael@0:   // It is always -1 in the parent process.  The parent keeps its end of the
michael@0:   // pipe in read_fd_.
michael@0:   int write_fd_;
michael@0: };
michael@0: 
michael@0: // Called in the parent process only. Reads the result code of the death
michael@0: // test child process via a pipe, interprets it to set the outcome_
michael@0: // member, and closes read_fd_.  Outputs diagnostics and terminates in
michael@0: // case of unexpected codes.
michael@0: void DeathTestImpl::ReadAndInterpretStatusByte() {
michael@0:   char flag;
michael@0:   int bytes_read;
michael@0: 
michael@0:   // The read() here blocks until data is available (signifying the
michael@0:   // failure of the death test) or until the pipe is closed (signifying
michael@0:   // its success), so it's okay to call this in the parent before
michael@0:   // the child process has exited.
michael@0:   do {
michael@0:     bytes_read = posix::Read(read_fd(), &flag, 1);
michael@0:   } while (bytes_read == -1 && errno == EINTR);
michael@0: 
michael@0:   if (bytes_read == 0) {
michael@0:     set_outcome(DIED);
michael@0:   } else if (bytes_read == 1) {
michael@0:     switch (flag) {
michael@0:       case kDeathTestReturned:
michael@0:         set_outcome(RETURNED);
michael@0:         break;
michael@0:       case kDeathTestThrew:
michael@0:         set_outcome(THREW);
michael@0:         break;
michael@0:       case kDeathTestLived:
michael@0:         set_outcome(LIVED);
michael@0:         break;
michael@0:       case kDeathTestInternalError:
michael@0:         FailFromInternalError(read_fd());  // Does not return.
michael@0:         break;
michael@0:       default:
michael@0:         GTEST_LOG_(FATAL) << "Death test child process reported "
michael@0:                           << "unexpected status byte ("
michael@0:                           << static_cast<unsigned int>(flag) << ")";
michael@0:     }
michael@0:   } else {
michael@0:     GTEST_LOG_(FATAL) << "Read from death test child process failed: "
michael@0:                       << GetLastErrnoDescription();
michael@0:   }
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));
michael@0:   set_read_fd(-1);
michael@0: }
michael@0: 
michael@0: // Signals that the death test code which should have exited, didn't.
michael@0: // Should be called only in a death test child process.
michael@0: // Writes a status byte to the child's status file descriptor, then
michael@0: // calls _exit(1).
michael@0: void DeathTestImpl::Abort(AbortReason reason) {
michael@0:   // The parent process considers the death test to be a failure if
michael@0:   // it finds any data in our pipe.  So, here we write a single flag byte
michael@0:   // to the pipe, then exit.
michael@0:   const char status_ch =
michael@0:       reason == TEST_DID_NOT_DIE ? kDeathTestLived :
michael@0:       reason == TEST_THREW_EXCEPTION ? kDeathTestThrew : kDeathTestReturned;
michael@0: 
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));
michael@0:   // We are leaking the descriptor here because on some platforms (i.e.,
michael@0:   // when built as Windows DLL), destructors of global objects will still
michael@0:   // run after calling _exit(). On such systems, write_fd_ will be
michael@0:   // indirectly closed from the destructor of UnitTestImpl, causing double
michael@0:   // close if it is also closed here. On debug configurations, double close
michael@0:   // may assert. As there are no in-process buffers to flush here, we are
michael@0:   // relying on the OS to close the descriptor after the process terminates
michael@0:   // when the destructors are not run.
michael@0:   _exit(1);  // Exits w/o any normal exit hooks (we were supposed to crash)
michael@0: }
michael@0: 
michael@0: // Returns an indented copy of stderr output for a death test.
michael@0: // This makes distinguishing death test output lines from regular log lines
michael@0: // much easier.
michael@0: static ::std::string FormatDeathTestOutput(const ::std::string& output) {
michael@0:   ::std::string ret;
michael@0:   for (size_t at = 0; ; ) {
michael@0:     const size_t line_end = output.find('\n', at);
michael@0:     ret += "[  DEATH   ] ";
michael@0:     if (line_end == ::std::string::npos) {
michael@0:       ret += output.substr(at);
michael@0:       break;
michael@0:     }
michael@0:     ret += output.substr(at, line_end + 1 - at);
michael@0:     at = line_end + 1;
michael@0:   }
michael@0:   return ret;
michael@0: }
michael@0: 
michael@0: // Assesses the success or failure of a death test, using both private
michael@0: // members which have previously been set, and one argument:
michael@0: //
michael@0: // Private data members:
michael@0: //   outcome:  An enumeration describing how the death test
michael@0: //             concluded: DIED, LIVED, THREW, or RETURNED.  The death test
michael@0: //             fails in the latter three cases.
michael@0: //   status:   The exit status of the child process. On *nix, it is in the
michael@0: //             in the format specified by wait(2). On Windows, this is the
michael@0: //             value supplied to the ExitProcess() API or a numeric code
michael@0: //             of the exception that terminated the program.
michael@0: //   regex:    A regular expression object to be applied to
michael@0: //             the test's captured standard error output; the death test
michael@0: //             fails if it does not match.
michael@0: //
michael@0: // Argument:
michael@0: //   status_ok: true if exit_status is acceptable in the context of
michael@0: //              this particular death test, which fails if it is false
michael@0: //
michael@0: // Returns true iff all of the above conditions are met.  Otherwise, the
michael@0: // first failing condition, in the order given above, is the one that is
michael@0: // reported. Also sets the last death test message string.
michael@0: bool DeathTestImpl::Passed(bool status_ok) {
michael@0:   if (!spawned())
michael@0:     return false;
michael@0: 
michael@0:   const String error_message = GetCapturedStderr();
michael@0: 
michael@0:   bool success = false;
michael@0:   Message buffer;
michael@0: 
michael@0:   buffer << "Death test: " << statement() << "\n";
michael@0:   switch (outcome()) {
michael@0:     case LIVED:
michael@0:       buffer << "    Result: failed to die.\n"
michael@0:              << " Error msg:\n" << FormatDeathTestOutput(error_message);
michael@0:       break;
michael@0:     case THREW:
michael@0:       buffer << "    Result: threw an exception.\n"
michael@0:              << " Error msg:\n" << FormatDeathTestOutput(error_message);
michael@0:       break;
michael@0:     case RETURNED:
michael@0:       buffer << "    Result: illegal return in test statement.\n"
michael@0:              << " Error msg:\n" << FormatDeathTestOutput(error_message);
michael@0:       break;
michael@0:     case DIED:
michael@0:       if (status_ok) {
michael@0:         const bool matched = RE::PartialMatch(error_message.c_str(), *regex());
michael@0:         if (matched) {
michael@0:           success = true;
michael@0:         } else {
michael@0:           buffer << "    Result: died but not with expected error.\n"
michael@0:                  << "  Expected: " << regex()->pattern() << "\n"
michael@0:                  << "Actual msg:\n" << FormatDeathTestOutput(error_message);
michael@0:         }
michael@0:       } else {
michael@0:         buffer << "    Result: died but not with expected exit code:\n"
michael@0:                << "            " << ExitSummary(status()) << "\n"
michael@0:                << "Actual msg:\n" << FormatDeathTestOutput(error_message);
michael@0:       }
michael@0:       break;
michael@0:     case IN_PROGRESS:
michael@0:     default:
michael@0:       GTEST_LOG_(FATAL)
michael@0:           << "DeathTest::Passed somehow called before conclusion of test";
michael@0:   }
michael@0: 
michael@0:   DeathTest::set_last_death_test_message(buffer.GetString());
michael@0:   return success;
michael@0: }
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: // WindowsDeathTest implements death tests on Windows. Due to the
michael@0: // specifics of starting new processes on Windows, death tests there are
michael@0: // always threadsafe, and Google Test considers the
michael@0: // --gtest_death_test_style=fast setting to be equivalent to
michael@0: // --gtest_death_test_style=threadsafe there.
michael@0: //
michael@0: // A few implementation notes:  Like the Linux version, the Windows
michael@0: // implementation uses pipes for child-to-parent communication. But due to
michael@0: // the specifics of pipes on Windows, some extra steps are required:
michael@0: //
michael@0: // 1. The parent creates a communication pipe and stores handles to both
michael@0: //    ends of it.
michael@0: // 2. The parent starts the child and provides it with the information
michael@0: //    necessary to acquire the handle to the write end of the pipe.
michael@0: // 3. The child acquires the write end of the pipe and signals the parent
michael@0: //    using a Windows event.
michael@0: // 4. Now the parent can release the write end of the pipe on its side. If
michael@0: //    this is done before step 3, the object's reference count goes down to
michael@0: //    0 and it is destroyed, preventing the child from acquiring it. The
michael@0: //    parent now has to release it, or read operations on the read end of
michael@0: //    the pipe will not return when the child terminates.
michael@0: // 5. The parent reads child's output through the pipe (outcome code and
michael@0: //    any possible error messages) from the pipe, and its stderr and then
michael@0: //    determines whether to fail the test.
michael@0: //
michael@0: // Note: to distinguish Win32 API calls from the local method and function
michael@0: // calls, the former are explicitly resolved in the global namespace.
michael@0: //
michael@0: class WindowsDeathTest : public DeathTestImpl {
michael@0:  public:
michael@0:   WindowsDeathTest(const char* a_statement,
michael@0:                    const RE* a_regex,
michael@0:                    const char* file,
michael@0:                    int line)
michael@0:       : DeathTestImpl(a_statement, a_regex), file_(file), line_(line) {}
michael@0: 
michael@0:   // All of these virtual functions are inherited from DeathTest.
michael@0:   virtual int Wait();
michael@0:   virtual TestRole AssumeRole();
michael@0: 
michael@0:  private:
michael@0:   // The name of the file in which the death test is located.
michael@0:   const char* const file_;
michael@0:   // The line number on which the death test is located.
michael@0:   const int line_;
michael@0:   // Handle to the write end of the pipe to the child process.
michael@0:   AutoHandle write_handle_;
michael@0:   // Child process handle.
michael@0:   AutoHandle child_handle_;
michael@0:   // Event the child process uses to signal the parent that it has
michael@0:   // acquired the handle to the write end of the pipe. After seeing this
michael@0:   // event the parent can release its own handles to make sure its
michael@0:   // ReadFile() calls return when the child terminates.
michael@0:   AutoHandle event_handle_;
michael@0: };
michael@0: 
michael@0: // Waits for the child in a death test to exit, returning its exit
michael@0: // status, or 0 if no child process exists.  As a side effect, sets the
michael@0: // outcome data member.
michael@0: int WindowsDeathTest::Wait() {
michael@0:   if (!spawned())
michael@0:     return 0;
michael@0: 
michael@0:   // Wait until the child either signals that it has acquired the write end
michael@0:   // of the pipe or it dies.
michael@0:   const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() };
michael@0:   switch (::WaitForMultipleObjects(2,
michael@0:                                    wait_handles,
michael@0:                                    FALSE,  // Waits for any of the handles.
michael@0:                                    INFINITE)) {
michael@0:     case WAIT_OBJECT_0:
michael@0:     case WAIT_OBJECT_0 + 1:
michael@0:       break;
michael@0:     default:
michael@0:       GTEST_DEATH_TEST_CHECK_(false);  // Should not get here.
michael@0:   }
michael@0: 
michael@0:   // The child has acquired the write end of the pipe or exited.
michael@0:   // We release the handle on our side and continue.
michael@0:   write_handle_.Reset();
michael@0:   event_handle_.Reset();
michael@0: 
michael@0:   ReadAndInterpretStatusByte();
michael@0: 
michael@0:   // Waits for the child process to exit if it haven't already. This
michael@0:   // returns immediately if the child has already exited, regardless of
michael@0:   // whether previous calls to WaitForMultipleObjects synchronized on this
michael@0:   // handle or not.
michael@0:   GTEST_DEATH_TEST_CHECK_(
michael@0:       WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(),
michael@0:                                              INFINITE));
michael@0:   DWORD status_code;
michael@0:   GTEST_DEATH_TEST_CHECK_(
michael@0:       ::GetExitCodeProcess(child_handle_.Get(), &status_code) != FALSE);
michael@0:   child_handle_.Reset();
michael@0:   set_status(static_cast<int>(status_code));
michael@0:   return status();
michael@0: }
michael@0: 
michael@0: // The AssumeRole process for a Windows death test.  It creates a child
michael@0: // process with the same executable as the current process to run the
michael@0: // death test.  The child process is given the --gtest_filter and
michael@0: // --gtest_internal_run_death_test flags such that it knows to run the
michael@0: // current death test only.
michael@0: DeathTest::TestRole WindowsDeathTest::AssumeRole() {
michael@0:   const UnitTestImpl* const impl = GetUnitTestImpl();
michael@0:   const InternalRunDeathTestFlag* const flag =
michael@0:       impl->internal_run_death_test_flag();
michael@0:   const TestInfo* const info = impl->current_test_info();
michael@0:   const int death_test_index = info->result()->death_test_count();
michael@0: 
michael@0:   if (flag != NULL) {
michael@0:     // ParseInternalRunDeathTestFlag() has performed all the necessary
michael@0:     // processing.
michael@0:     set_write_fd(flag->write_fd());
michael@0:     return EXECUTE_TEST;
michael@0:   }
michael@0: 
michael@0:   // WindowsDeathTest uses an anonymous pipe to communicate results of
michael@0:   // a death test.
michael@0:   SECURITY_ATTRIBUTES handles_are_inheritable = {
michael@0:     sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
michael@0:   HANDLE read_handle, write_handle;
michael@0:   GTEST_DEATH_TEST_CHECK_(
michael@0:       ::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable,
michael@0:                    0)  // Default buffer size.
michael@0:       != FALSE);
michael@0:   set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle),
michael@0:                                 O_RDONLY));
michael@0:   write_handle_.Reset(write_handle);
michael@0:   event_handle_.Reset(::CreateEvent(
michael@0:       &handles_are_inheritable,
michael@0:       TRUE,    // The event will automatically reset to non-signaled state.
michael@0:       FALSE,   // The initial state is non-signalled.
michael@0:       NULL));  // The even is unnamed.
michael@0:   GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL);
michael@0:   const String filter_flag = String::Format("--%s%s=%s.%s",
michael@0:                                             GTEST_FLAG_PREFIX_, kFilterFlag,
michael@0:                                             info->test_case_name(),
michael@0:                                             info->name());
michael@0:   const String internal_flag = String::Format(
michael@0:     "--%s%s=%s|%d|%d|%u|%Iu|%Iu",
michael@0:       GTEST_FLAG_PREFIX_,
michael@0:       kInternalRunDeathTestFlag,
michael@0:       file_, line_,
michael@0:       death_test_index,
michael@0:       static_cast<unsigned int>(::GetCurrentProcessId()),
michael@0:       // size_t has the same with as pointers on both 32-bit and 64-bit
michael@0:       // Windows platforms.
michael@0:       // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
michael@0:       reinterpret_cast<size_t>(write_handle),
michael@0:       reinterpret_cast<size_t>(event_handle_.Get()));
michael@0: 
michael@0:   char executable_path[_MAX_PATH + 1];  // NOLINT
michael@0:   GTEST_DEATH_TEST_CHECK_(
michael@0:       _MAX_PATH + 1 != ::GetModuleFileNameA(NULL,
michael@0:                                             executable_path,
michael@0:                                             _MAX_PATH));
michael@0: 
michael@0:   String command_line = String::Format("%s %s \"%s\"",
michael@0:                                        ::GetCommandLineA(),
michael@0:                                        filter_flag.c_str(),
michael@0:                                        internal_flag.c_str());
michael@0: 
michael@0:   DeathTest::set_last_death_test_message("");
michael@0: 
michael@0:   CaptureStderr();
michael@0:   // Flush the log buffers since the log streams are shared with the child.
michael@0:   FlushInfoLog();
michael@0: 
michael@0:   // The child process will share the standard handles with the parent.
michael@0:   STARTUPINFOA startup_info;
michael@0:   memset(&startup_info, 0, sizeof(STARTUPINFO));
michael@0:   startup_info.dwFlags = STARTF_USESTDHANDLES;
michael@0:   startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
michael@0:   startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
michael@0:   startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);
michael@0: 
michael@0:   PROCESS_INFORMATION process_info;
michael@0:   GTEST_DEATH_TEST_CHECK_(::CreateProcessA(
michael@0:       executable_path,
michael@0:       const_cast<char*>(command_line.c_str()),
michael@0:       NULL,   // Retuned process handle is not inheritable.
michael@0:       NULL,   // Retuned thread handle is not inheritable.
michael@0:       TRUE,   // Child inherits all inheritable handles (for write_handle_).
michael@0:       0x0,    // Default creation flags.
michael@0:       NULL,   // Inherit the parent's environment.
michael@0:       UnitTest::GetInstance()->original_working_dir(),
michael@0:       &startup_info,
michael@0:       &process_info) != FALSE);
michael@0:   child_handle_.Reset(process_info.hProcess);
michael@0:   ::CloseHandle(process_info.hThread);
michael@0:   set_spawned(true);
michael@0:   return OVERSEE_TEST;
michael@0: }
michael@0: # else  // We are not on Windows.
michael@0: 
michael@0: // ForkingDeathTest provides implementations for most of the abstract
michael@0: // methods of the DeathTest interface.  Only the AssumeRole method is
michael@0: // left undefined.
michael@0: class ForkingDeathTest : public DeathTestImpl {
michael@0:  public:
michael@0:   ForkingDeathTest(const char* statement, const RE* regex);
michael@0: 
michael@0:   // All of these virtual functions are inherited from DeathTest.
michael@0:   virtual int Wait();
michael@0: 
michael@0:  protected:
michael@0:   void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }
michael@0: 
michael@0:  private:
michael@0:   // PID of child process during death test; 0 in the child process itself.
michael@0:   pid_t child_pid_;
michael@0: };
michael@0: 
michael@0: // Constructs a ForkingDeathTest.
michael@0: ForkingDeathTest::ForkingDeathTest(const char* a_statement, const RE* a_regex)
michael@0:     : DeathTestImpl(a_statement, a_regex),
michael@0:       child_pid_(-1) {}
michael@0: 
michael@0: // Waits for the child in a death test to exit, returning its exit
michael@0: // status, or 0 if no child process exists.  As a side effect, sets the
michael@0: // outcome data member.
michael@0: int ForkingDeathTest::Wait() {
michael@0:   if (!spawned())
michael@0:     return 0;
michael@0: 
michael@0:   ReadAndInterpretStatusByte();
michael@0: 
michael@0:   int status_value;
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status_value, 0));
michael@0:   set_status(status_value);
michael@0:   return status_value;
michael@0: }
michael@0: 
michael@0: // A concrete death test class that forks, then immediately runs the test
michael@0: // in the child process.
michael@0: class NoExecDeathTest : public ForkingDeathTest {
michael@0:  public:
michael@0:   NoExecDeathTest(const char* a_statement, const RE* a_regex) :
michael@0:       ForkingDeathTest(a_statement, a_regex) { }
michael@0:   virtual TestRole AssumeRole();
michael@0: };
michael@0: 
michael@0: // The AssumeRole process for a fork-and-run death test.  It implements a
michael@0: // straightforward fork, with a simple pipe to transmit the status byte.
michael@0: DeathTest::TestRole NoExecDeathTest::AssumeRole() {
michael@0:   const size_t thread_count = GetThreadCount();
michael@0:   if (thread_count != 1) {
michael@0:     GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);
michael@0:   }
michael@0: 
michael@0:   int pipe_fd[2];
michael@0:   GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
michael@0: 
michael@0:   DeathTest::set_last_death_test_message("");
michael@0:   CaptureStderr();
michael@0:   // When we fork the process below, the log file buffers are copied, but the
michael@0:   // file descriptors are shared.  We flush all log files here so that closing
michael@0:   // the file descriptors in the child process doesn't throw off the
michael@0:   // synchronization between descriptors and buffers in the parent process.
michael@0:   // This is as close to the fork as possible to avoid a race condition in case
michael@0:   // there are multiple threads running before the death test, and another
michael@0:   // thread writes to the log file.
michael@0:   FlushInfoLog();
michael@0: 
michael@0:   const pid_t child_pid = fork();
michael@0:   GTEST_DEATH_TEST_CHECK_(child_pid != -1);
michael@0:   set_child_pid(child_pid);
michael@0:   if (child_pid == 0) {
michael@0:     GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));
michael@0:     set_write_fd(pipe_fd[1]);
michael@0:     // Redirects all logging to stderr in the child process to prevent
michael@0:     // concurrent writes to the log files.  We capture stderr in the parent
michael@0:     // process and append the child process' output to a log.
michael@0:     LogToStderr();
michael@0:     // Event forwarding to the listeners of event listener API mush be shut
michael@0:     // down in death test subprocesses.
michael@0:     GetUnitTestImpl()->listeners()->SuppressEventForwarding();
michael@0:     g_in_fast_death_test_child = true;
michael@0:     return EXECUTE_TEST;
michael@0:   } else {
michael@0:     GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
michael@0:     set_read_fd(pipe_fd[0]);
michael@0:     set_spawned(true);
michael@0:     return OVERSEE_TEST;
michael@0:   }
michael@0: }
michael@0: 
michael@0: // A concrete death test class that forks and re-executes the main
michael@0: // program from the beginning, with command-line flags set that cause
michael@0: // only this specific death test to be run.
michael@0: class ExecDeathTest : public ForkingDeathTest {
michael@0:  public:
michael@0:   ExecDeathTest(const char* a_statement, const RE* a_regex,
michael@0:                 const char* file, int line) :
michael@0:       ForkingDeathTest(a_statement, a_regex), file_(file), line_(line) { }
michael@0:   virtual TestRole AssumeRole();
michael@0:  private:
michael@0:   static ::std::vector<testing::internal::string>
michael@0:   GetArgvsForDeathTestChildProcess() {
michael@0:     ::std::vector<testing::internal::string> args = GetInjectableArgvs();
michael@0:     return args;
michael@0:   }
michael@0:   // The name of the file in which the death test is located.
michael@0:   const char* const file_;
michael@0:   // The line number on which the death test is located.
michael@0:   const int line_;
michael@0: };
michael@0: 
michael@0: // Utility class for accumulating command-line arguments.
michael@0: class Arguments {
michael@0:  public:
michael@0:   Arguments() {
michael@0:     args_.push_back(NULL);
michael@0:   }
michael@0: 
michael@0:   ~Arguments() {
michael@0:     for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
michael@0:          ++i) {
michael@0:       free(*i);
michael@0:     }
michael@0:   }
michael@0:   void AddArgument(const char* argument) {
michael@0:     args_.insert(args_.end() - 1, posix::StrDup(argument));
michael@0:   }
michael@0: 
michael@0:   template <typename Str>
michael@0:   void AddArguments(const ::std::vector<Str>& arguments) {
michael@0:     for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
michael@0:          i != arguments.end();
michael@0:          ++i) {
michael@0:       args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));
michael@0:     }
michael@0:   }
michael@0:   char* const* Argv() {
michael@0:     return &args_[0];
michael@0:   }
michael@0: 
michael@0:  private:
michael@0:   std::vector<char*> args_;
michael@0: };
michael@0: 
michael@0: // A struct that encompasses the arguments to the child process of a
michael@0: // threadsafe-style death test process.
michael@0: struct ExecDeathTestArgs {
michael@0:   char* const* argv;  // Command-line arguments for the child's call to exec
michael@0:   int close_fd;       // File descriptor to close; the read end of a pipe
michael@0: };
michael@0: 
michael@0: #  if GTEST_OS_MAC
michael@0: inline char** GetEnviron() {
michael@0:   // When Google Test is built as a framework on MacOS X, the environ variable
michael@0:   // is unavailable. Apple's documentation (man environ) recommends using
michael@0:   // _NSGetEnviron() instead.
michael@0:   return *_NSGetEnviron();
michael@0: }
michael@0: #  else
michael@0: // Some POSIX platforms expect you to declare environ. extern "C" makes
michael@0: // it reside in the global namespace.
michael@0: extern "C" __attribute__ ((visibility ("default"))) char** environ;
michael@0: inline char** GetEnviron() { return environ; }
michael@0: #  endif  // GTEST_OS_MAC
michael@0: 
michael@0: #  if !GTEST_OS_QNX
michael@0: // The main function for a threadsafe-style death test child process.
michael@0: // This function is called in a clone()-ed process and thus must avoid
michael@0: // any potentially unsafe operations like malloc or libc functions.
michael@0: static int ExecDeathTestChildMain(void* child_arg) {
michael@0:   ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg);
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));
michael@0: 
michael@0:   // We need to execute the test program in the same environment where
michael@0:   // it was originally invoked.  Therefore we change to the original
michael@0:   // working directory first.
michael@0:   const char* const original_dir =
michael@0:       UnitTest::GetInstance()->original_working_dir();
michael@0:   // We can safely call chdir() as it's a direct system call.
michael@0:   if (chdir(original_dir) != 0) {
michael@0:     DeathTestAbort(String::Format("chdir(\"%s\") failed: %s",
michael@0:                                   original_dir,
michael@0:                                   GetLastErrnoDescription().c_str()));
michael@0:     return EXIT_FAILURE;
michael@0:   }
michael@0: 
michael@0:   // We can safely call execve() as it's a direct system call.  We
michael@0:   // cannot use execvp() as it's a libc function and thus potentially
michael@0:   // unsafe.  Since execve() doesn't search the PATH, the user must
michael@0:   // invoke the test program via a valid path that contains at least
michael@0:   // one path separator.
michael@0:   execve(args->argv[0], args->argv, GetEnviron());
michael@0:   DeathTestAbort(String::Format("execve(%s, ...) in %s failed: %s",
michael@0:                                 args->argv[0],
michael@0:                                 original_dir,
michael@0:                                 GetLastErrnoDescription().c_str()));
michael@0:   return EXIT_FAILURE;
michael@0: }
michael@0: #  endif  // !GTEST_OS_QNX
michael@0: 
michael@0: // Two utility routines that together determine the direction the stack
michael@0: // grows.
michael@0: // This could be accomplished more elegantly by a single recursive
michael@0: // function, but we want to guard against the unlikely possibility of
michael@0: // a smart compiler optimizing the recursion away.
michael@0: //
michael@0: // GTEST_NO_INLINE_ is required to prevent GCC 4.6 from inlining
michael@0: // StackLowerThanAddress into StackGrowsDown, which then doesn't give
michael@0: // correct answer.
michael@0: void StackLowerThanAddress(const void* ptr, bool* result) GTEST_NO_INLINE_;
michael@0: void StackLowerThanAddress(const void* ptr, bool* result) {
michael@0:   int dummy;
michael@0:   *result = (&dummy < ptr);
michael@0: }
michael@0: 
michael@0: bool StackGrowsDown() {
michael@0:   int dummy;
michael@0:   bool result;
michael@0:   StackLowerThanAddress(&dummy, &result);
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: // Spawns a child process with the same executable as the current process in
michael@0: // a thread-safe manner and instructs it to run the death test.  The
michael@0: // implementation uses fork(2) + exec.  On systems where clone(2) is
michael@0: // available, it is used instead, being slightly more thread-safe.  On QNX,
michael@0: // fork supports only single-threaded environments, so this function uses
michael@0: // spawn(2) there instead.  The function dies with an error message if
michael@0: // anything goes wrong.
michael@0: static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
michael@0:   ExecDeathTestArgs args = { argv, close_fd };
michael@0:   pid_t child_pid = -1;
michael@0: 
michael@0: #  if GTEST_OS_QNX
michael@0:   // Obtains the current directory and sets it to be closed in the child
michael@0:   // process.
michael@0:   const int cwd_fd = open(".", O_RDONLY);
michael@0:   GTEST_DEATH_TEST_CHECK_(cwd_fd != -1);
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(cwd_fd, F_SETFD, FD_CLOEXEC));
michael@0:   // We need to execute the test program in the same environment where
michael@0:   // it was originally invoked.  Therefore we change to the original
michael@0:   // working directory first.
michael@0:   const char* const original_dir =
michael@0:       UnitTest::GetInstance()->original_working_dir();
michael@0:   // We can safely call chdir() as it's a direct system call.
michael@0:   if (chdir(original_dir) != 0) {
michael@0:     DeathTestAbort(String::Format("chdir(\"%s\") failed: %s",
michael@0:                                   original_dir,
michael@0:                                   GetLastErrnoDescription().c_str()));
michael@0:     return EXIT_FAILURE;
michael@0:   }
michael@0: 
michael@0:   int fd_flags;
michael@0:   // Set close_fd to be closed after spawn.
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(fd_flags = fcntl(close_fd, F_GETFD));
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(fcntl(close_fd, F_SETFD,
michael@0:                                         fd_flags | FD_CLOEXEC));
michael@0:   struct inheritance inherit = {0};
michael@0:   // spawn is a system call.
michael@0:   child_pid = spawn(args.argv[0], 0, NULL, &inherit, args.argv, GetEnviron());
michael@0:   // Restores the current working directory.
michael@0:   GTEST_DEATH_TEST_CHECK_(fchdir(cwd_fd) != -1);
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(close(cwd_fd));
michael@0: 
michael@0: #  else   // GTEST_OS_QNX
michael@0: #   if GTEST_OS_LINUX
michael@0:   // When a SIGPROF signal is received while fork() or clone() are executing,
michael@0:   // the process may hang. To avoid this, we ignore SIGPROF here and re-enable
michael@0:   // it after the call to fork()/clone() is complete.
michael@0:   struct sigaction saved_sigprof_action;
michael@0:   struct sigaction ignore_sigprof_action;
michael@0:   memset(&ignore_sigprof_action, 0, sizeof(ignore_sigprof_action));
michael@0:   sigemptyset(&ignore_sigprof_action.sa_mask);
michael@0:   ignore_sigprof_action.sa_handler = SIG_IGN;
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(sigaction(
michael@0:       SIGPROF, &ignore_sigprof_action, &saved_sigprof_action));
michael@0: #   endif  // GTEST_OS_LINUX
michael@0: 
michael@0: #   if GTEST_HAS_CLONE
michael@0:   const bool use_fork = GTEST_FLAG(death_test_use_fork);
michael@0: 
michael@0:   if (!use_fork) {
michael@0:     static const bool stack_grows_down = StackGrowsDown();
michael@0:     const size_t stack_size = getpagesize();
michael@0:     // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
michael@0:     void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
michael@0:                              MAP_ANON | MAP_PRIVATE, -1, 0);
michael@0:     GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
michael@0: 
michael@0:     // Maximum stack alignment in bytes:  For a downward-growing stack, this
michael@0:     // amount is subtracted from size of the stack space to get an address
michael@0:     // that is within the stack space and is aligned on all systems we care
michael@0:     // about.  As far as I know there is no ABI with stack alignment greater
michael@0:     // than 64.  We assume stack and stack_size already have alignment of
michael@0:     // kMaxStackAlignment.
michael@0:     const size_t kMaxStackAlignment = 64;
michael@0:     void* const stack_top =
michael@0:         static_cast<char*>(stack) +
michael@0:             (stack_grows_down ? stack_size - kMaxStackAlignment : 0);
michael@0:     GTEST_DEATH_TEST_CHECK_(stack_size > kMaxStackAlignment &&
michael@0:         reinterpret_cast<intptr_t>(stack_top) % kMaxStackAlignment == 0);
michael@0: 
michael@0:     child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);
michael@0: 
michael@0:     GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
michael@0:   }
michael@0: #   else
michael@0:   const bool use_fork = true;
michael@0: #   endif  // GTEST_HAS_CLONE
michael@0: 
michael@0:   if (use_fork && (child_pid = fork()) == 0) {
michael@0:       ExecDeathTestChildMain(&args);
michael@0:       _exit(0);
michael@0:   }
michael@0: #  endif  // GTEST_OS_QNX
michael@0: #  if GTEST_OS_LINUX
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(
michael@0:       sigaction(SIGPROF, &saved_sigprof_action, NULL));
michael@0: #  endif  // GTEST_OS_LINUX
michael@0: 
michael@0:   GTEST_DEATH_TEST_CHECK_(child_pid != -1);
michael@0:   return child_pid;
michael@0: }
michael@0: 
michael@0: // The AssumeRole process for a fork-and-exec death test.  It re-executes the
michael@0: // main program from the beginning, setting the --gtest_filter
michael@0: // and --gtest_internal_run_death_test flags to cause only the current
michael@0: // death test to be re-run.
michael@0: DeathTest::TestRole ExecDeathTest::AssumeRole() {
michael@0:   const UnitTestImpl* const impl = GetUnitTestImpl();
michael@0:   const InternalRunDeathTestFlag* const flag =
michael@0:       impl->internal_run_death_test_flag();
michael@0:   const TestInfo* const info = impl->current_test_info();
michael@0:   const int death_test_index = info->result()->death_test_count();
michael@0: 
michael@0:   if (flag != NULL) {
michael@0:     set_write_fd(flag->write_fd());
michael@0:     return EXECUTE_TEST;
michael@0:   }
michael@0: 
michael@0:   int pipe_fd[2];
michael@0:   GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
michael@0:   // Clear the close-on-exec flag on the write end of the pipe, lest
michael@0:   // it be closed when the child process does an exec:
michael@0:   GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
michael@0: 
michael@0:   const String filter_flag =
michael@0:       String::Format("--%s%s=%s.%s",
michael@0:                      GTEST_FLAG_PREFIX_, kFilterFlag,
michael@0:                      info->test_case_name(), info->name());
michael@0:   const String internal_flag =
michael@0:       String::Format("--%s%s=%s|%d|%d|%d",
michael@0:                      GTEST_FLAG_PREFIX_, kInternalRunDeathTestFlag,
michael@0:                      file_, line_, death_test_index, pipe_fd[1]);
michael@0:   Arguments args;
michael@0:   args.AddArguments(GetArgvsForDeathTestChildProcess());
michael@0:   args.AddArgument(filter_flag.c_str());
michael@0:   args.AddArgument(internal_flag.c_str());
michael@0: 
michael@0:   DeathTest::set_last_death_test_message("");
michael@0: 
michael@0:   CaptureStderr();
michael@0:   // See the comment in NoExecDeathTest::AssumeRole for why the next line
michael@0:   // is necessary.
michael@0:   FlushInfoLog();
michael@0: 
michael@0:   const pid_t child_pid = ExecDeathTestSpawnChild(args.Argv(), pipe_fd[0]);
michael@0:   GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
michael@0:   set_child_pid(child_pid);
michael@0:   set_read_fd(pipe_fd[0]);
michael@0:   set_spawned(true);
michael@0:   return OVERSEE_TEST;
michael@0: }
michael@0: 
michael@0: # endif  // !GTEST_OS_WINDOWS
michael@0: 
michael@0: // Creates a concrete DeathTest-derived class that depends on the
michael@0: // --gtest_death_test_style flag, and sets the pointer pointed to
michael@0: // by the "test" argument to its address.  If the test should be
michael@0: // skipped, sets that pointer to NULL.  Returns true, unless the
michael@0: // flag is set to an invalid value.
michael@0: bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
michael@0:                                      const char* file, int line,
michael@0:                                      DeathTest** test) {
michael@0:   UnitTestImpl* const impl = GetUnitTestImpl();
michael@0:   const InternalRunDeathTestFlag* const flag =
michael@0:       impl->internal_run_death_test_flag();
michael@0:   const int death_test_index = impl->current_test_info()
michael@0:       ->increment_death_test_count();
michael@0: 
michael@0:   if (flag != NULL) {
michael@0:     if (death_test_index > flag->index()) {
michael@0:       DeathTest::set_last_death_test_message(String::Format(
michael@0:           "Death test count (%d) somehow exceeded expected maximum (%d)",
michael@0:           death_test_index, flag->index()));
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     if (!(flag->file() == file && flag->line() == line &&
michael@0:           flag->index() == death_test_index)) {
michael@0:       *test = NULL;
michael@0:       return true;
michael@0:     }
michael@0:   }
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: 
michael@0:   if (GTEST_FLAG(death_test_style) == "threadsafe" ||
michael@0:       GTEST_FLAG(death_test_style) == "fast") {
michael@0:     *test = new WindowsDeathTest(statement, regex, file, line);
michael@0:   }
michael@0: 
michael@0: # else
michael@0: 
michael@0:   if (GTEST_FLAG(death_test_style) == "threadsafe") {
michael@0:     *test = new ExecDeathTest(statement, regex, file, line);
michael@0:   } else if (GTEST_FLAG(death_test_style) == "fast") {
michael@0:     *test = new NoExecDeathTest(statement, regex);
michael@0:   }
michael@0: 
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: 
michael@0:   else {  // NOLINT - this is more readable than unbalanced brackets inside #if.
michael@0:     DeathTest::set_last_death_test_message(String::Format(
michael@0:         "Unknown death test style \"%s\" encountered",
michael@0:         GTEST_FLAG(death_test_style).c_str()));
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: // Splits a given string on a given delimiter, populating a given
michael@0: // vector with the fields.  GTEST_HAS_DEATH_TEST implies that we have
michael@0: // ::std::string, so we can use it here.
michael@0: static void SplitString(const ::std::string& str, char delimiter,
michael@0:                         ::std::vector< ::std::string>* dest) {
michael@0:   ::std::vector< ::std::string> parsed;
michael@0:   ::std::string::size_type pos = 0;
michael@0:   while (::testing::internal::AlwaysTrue()) {
michael@0:     const ::std::string::size_type colon = str.find(delimiter, pos);
michael@0:     if (colon == ::std::string::npos) {
michael@0:       parsed.push_back(str.substr(pos));
michael@0:       break;
michael@0:     } else {
michael@0:       parsed.push_back(str.substr(pos, colon - pos));
michael@0:       pos = colon + 1;
michael@0:     }
michael@0:   }
michael@0:   dest->swap(parsed);
michael@0: }
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: // Recreates the pipe and event handles from the provided parameters,
michael@0: // signals the event, and returns a file descriptor wrapped around the pipe
michael@0: // handle. This function is called in the child process only.
michael@0: int GetStatusFileDescriptor(unsigned int parent_process_id,
michael@0:                             size_t write_handle_as_size_t,
michael@0:                             size_t event_handle_as_size_t) {
michael@0:   AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
michael@0:                                                    FALSE,  // Non-inheritable.
michael@0:                                                    parent_process_id));
michael@0:   if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
michael@0:     DeathTestAbort(String::Format("Unable to open parent process %u",
michael@0:                                   parent_process_id));
michael@0:   }
michael@0: 
michael@0:   // TODO(vladl@google.com): Replace the following check with a
michael@0:   // compile-time assertion when available.
michael@0:   GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));
michael@0: 
michael@0:   const HANDLE write_handle =
michael@0:       reinterpret_cast<HANDLE>(write_handle_as_size_t);
michael@0:   HANDLE dup_write_handle;
michael@0: 
michael@0:   // The newly initialized handle is accessible only in in the parent
michael@0:   // process. To obtain one accessible within the child, we need to use
michael@0:   // DuplicateHandle.
michael@0:   if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
michael@0:                          ::GetCurrentProcess(), &dup_write_handle,
michael@0:                          0x0,    // Requested privileges ignored since
michael@0:                                  // DUPLICATE_SAME_ACCESS is used.
michael@0:                          FALSE,  // Request non-inheritable handler.
michael@0:                          DUPLICATE_SAME_ACCESS)) {
michael@0:     DeathTestAbort(String::Format(
michael@0:         "Unable to duplicate the pipe handle %Iu from the parent process %u",
michael@0:         write_handle_as_size_t, parent_process_id));
michael@0:   }
michael@0: 
michael@0:   const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
michael@0:   HANDLE dup_event_handle;
michael@0: 
michael@0:   if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
michael@0:                          ::GetCurrentProcess(), &dup_event_handle,
michael@0:                          0x0,
michael@0:                          FALSE,
michael@0:                          DUPLICATE_SAME_ACCESS)) {
michael@0:     DeathTestAbort(String::Format(
michael@0:         "Unable to duplicate the event handle %Iu from the parent process %u",
michael@0:         event_handle_as_size_t, parent_process_id));
michael@0:   }
michael@0: 
michael@0:   const int write_fd =
michael@0:       ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
michael@0:   if (write_fd == -1) {
michael@0:     DeathTestAbort(String::Format(
michael@0:         "Unable to convert pipe handle %Iu to a file descriptor",
michael@0:         write_handle_as_size_t));
michael@0:   }
michael@0: 
michael@0:   // Signals the parent that the write end of the pipe has been acquired
michael@0:   // so the parent can release its own write end.
michael@0:   ::SetEvent(dup_event_handle);
michael@0: 
michael@0:   return write_fd;
michael@0: }
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: 
michael@0: // Returns a newly created InternalRunDeathTestFlag object with fields
michael@0: // initialized from the GTEST_FLAG(internal_run_death_test) flag if
michael@0: // the flag is specified; otherwise returns NULL.
michael@0: InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
michael@0:   if (GTEST_FLAG(internal_run_death_test) == "") return NULL;
michael@0: 
michael@0:   // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
michael@0:   // can use it here.
michael@0:   int line = -1;
michael@0:   int index = -1;
michael@0:   ::std::vector< ::std::string> fields;
michael@0:   SplitString(GTEST_FLAG(internal_run_death_test).c_str(), '|', &fields);
michael@0:   int write_fd = -1;
michael@0: 
michael@0: # if GTEST_OS_WINDOWS
michael@0: 
michael@0:   unsigned int parent_process_id = 0;
michael@0:   size_t write_handle_as_size_t = 0;
michael@0:   size_t event_handle_as_size_t = 0;
michael@0: 
michael@0:   if (fields.size() != 6
michael@0:       || !ParseNaturalNumber(fields[1], &line)
michael@0:       || !ParseNaturalNumber(fields[2], &index)
michael@0:       || !ParseNaturalNumber(fields[3], &parent_process_id)
michael@0:       || !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
michael@0:       || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
michael@0:     DeathTestAbort(String::Format(
michael@0:         "Bad --gtest_internal_run_death_test flag: %s",
michael@0:         GTEST_FLAG(internal_run_death_test).c_str()));
michael@0:   }
michael@0:   write_fd = GetStatusFileDescriptor(parent_process_id,
michael@0:                                      write_handle_as_size_t,
michael@0:                                      event_handle_as_size_t);
michael@0: # else
michael@0: 
michael@0:   if (fields.size() != 4
michael@0:       || !ParseNaturalNumber(fields[1], &line)
michael@0:       || !ParseNaturalNumber(fields[2], &index)
michael@0:       || !ParseNaturalNumber(fields[3], &write_fd)) {
michael@0:     DeathTestAbort(String::Format(
michael@0:         "Bad --gtest_internal_run_death_test flag: %s",
michael@0:         GTEST_FLAG(internal_run_death_test).c_str()));
michael@0:   }
michael@0: 
michael@0: # endif  // GTEST_OS_WINDOWS
michael@0: 
michael@0:   return new InternalRunDeathTestFlag(fields[0], line, index, write_fd);
michael@0: }
michael@0: 
michael@0: }  // namespace internal
michael@0: 
michael@0: #endif  // GTEST_HAS_DEATH_TEST
michael@0: 
michael@0: }  // namespace testing