// Copyright 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: wan@google.com (Zhanyong Wan), vladl@google.com (Vlad Losev)
//
// This file implements death tests.
#include <gtest/gtest-death-test.h>
#include <gtest/internal/gtest-port.h>
#if GTEST_HAS_DEATH_TEST
#if GTEST_OS_MAC
#include <crt_externs.h>
#endif // GTEST_OS_MAC
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdarg.h>
#if GTEST_OS_WINDOWS
#include <windows.h>
#else
#include <sys/mman.h>
#include <sys/wait.h>
#endif // GTEST_OS_WINDOWS
#endif // GTEST_HAS_DEATH_TEST
#include <gtest/gtest-message.h>
#include <gtest/internal/gtest-string.h>
// Indicates that this translation unit is part of Google Test's
// implementation. It must come before gtest-internal-inl.h is
// included, or there will be a compiler error. This trick is to
// prevent a user from accidentally including gtest-internal-inl.h in
// his code.
#define GTEST_IMPLEMENTATION_ 1
#include "src/gtest-internal-inl.h"
#undef GTEST_IMPLEMENTATION_
namespace testing {
// Constants.
// The default death test style.
static const char kDefaultDeathTestStyle[] = "fast";
GTEST_DEFINE_string_(
death_test_style,
internal::StringFromGTestEnv("death_test_style", kDefaultDeathTestStyle),
"Indicates how to run a death test in a forked child process: "
"\"threadsafe\" (child process re-executes the test binary "
"from the beginning, running only the specific death test) or "
"\"fast\" (child process runs the death test immediately "
"after forking).");
GTEST_DEFINE_bool_(
death_test_use_fork,
internal::BoolFromGTestEnv("death_test_use_fork", false),
"Instructs to use fork()/_exit() instead of clone() in death tests. "
"Ignored and always uses fork() on POSIX systems where clone() is not "
"implemented. Useful when running under valgrind or similar tools if "
"those do not support clone(). Valgrind 3.3.1 will just fail if "
"it sees an unsupported combination of clone() flags. "
"It is not recommended to use this flag w/o valgrind though it will "
"work in 99% of the cases. Once valgrind is fixed, this flag will "
"most likely be removed.");
namespace internal {
GTEST_DEFINE_string_(
internal_run_death_test, "",
"Indicates the file, line number, temporal index of "
"the single death test to run, and a file descriptor to "
"which a success code may be sent, all separated by "
"colons. This flag is specified if and only if the current "
"process is a sub-process launched for running a thread-safe "
"death test. FOR INTERNAL USE ONLY.");
} // namespace internal
#if GTEST_HAS_DEATH_TEST
// ExitedWithCode constructor.
ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
}
// ExitedWithCode function-call operator.
bool ExitedWithCode::operator()(int exit_status) const {
#if GTEST_OS_WINDOWS
return exit_status == exit_code_;
#else
return WIFEXITED(exit_status) && WEXITSTATUS(exit_status) == exit_code_;
#endif // GTEST_OS_WINDOWS
}
#if !GTEST_OS_WINDOWS
// KilledBySignal constructor.
KilledBySignal::KilledBySignal(int signum) : signum_(signum) {
}
// KilledBySignal function-call operator.
bool KilledBySignal::operator()(int exit_status) const {
return WIFSIGNALED(exit_status) && WTERMSIG(exit_status) == signum_;
}
#endif // !GTEST_OS_WINDOWS
namespace internal {
// Utilities needed for death tests.
// Generates a textual description of a given exit code, in the format
// specified by wait(2).
static String ExitSummary(int exit_code) {
Message m;
#if GTEST_OS_WINDOWS
m << "Exited with exit status " << exit_code;
#else
if (WIFEXITED(exit_code)) {
m << "Exited with exit status " << WEXITSTATUS(exit_code);
} else if (WIFSIGNALED(exit_code)) {
m << "Terminated by signal " << WTERMSIG(exit_code);
}
#ifdef WCOREDUMP
if (WCOREDUMP(exit_code)) {
m << " (core dumped)";
}
#endif
#endif // GTEST_OS_WINDOWS
return m.GetString();
}
// Returns true if exit_status describes a process that was terminated
// by a signal, or exited normally with a nonzero exit code.
bool ExitedUnsuccessfully(int exit_status) {
return !ExitedWithCode(0)(exit_status);
}
#if !GTEST_OS_WINDOWS
// Generates a textual failure message when a death test finds more than
// one thread running, or cannot determine the number of threads, prior
// to executing the given statement. It is the responsibility of the
// caller not to pass a thread_count of 1.
static String DeathTestThreadWarning(size_t thread_count) {
Message msg;
msg << "Death tests use fork(), which is unsafe particularly"
<< " in a threaded context. For this test, " << GTEST_NAME_ << " ";
if (thread_count == 0)
msg << "couldn't detect the number of threads.";
else
msg << "detected " << thread_count << " threads.";
return msg.GetString();
}
#endif // !GTEST_OS_WINDOWS
// Flag characters for reporting a death test that did not die.
static const char kDeathTestLived = 'L';
static const char kDeathTestReturned = 'R';
static const char kDeathTestInternalError = 'I';
// An enumeration describing all of the possible ways that a death test
// can conclude. DIED means that the process died while executing the
// test code; LIVED means that process lived beyond the end of the test
// code; and RETURNED means that the test statement attempted a "return,"
// which is not allowed. IN_PROGRESS means the test has not yet
// concluded.
enum DeathTestOutcome { IN_PROGRESS, DIED, LIVED, RETURNED };
// Routine for aborting the program which is safe to call from an
// exec-style death test child process, in which case the error
// message is propagated back to the parent process. Otherwise, the
// message is simply printed to stderr. In either case, the program
// then exits with status 1.
void DeathTestAbort(const String& message) {
// On a POSIX system, this function may be called from a threadsafe-style
// death test child process, which operates on a very small stack. Use
// the heap for any additional non-minuscule memory requirements.
const InternalRunDeathTestFlag* const flag =
GetUnitTestImpl()->internal_run_death_test_flag();
if (flag != NULL) {
FILE* parent = posix::FDOpen(flag->write_fd(), "w");
fputc(kDeathTestInternalError, parent);
fprintf(parent, "%s", message.c_str());
fflush(parent);
_exit(1);
} else {
fprintf(stderr, "%s", message.c_str());
fflush(stderr);
abort();
}
}
// A replacement for CHECK that calls DeathTestAbort if the assertion
// fails.
#define GTEST_DEATH_TEST_CHECK_(expression) \
do { \
if (!::testing::internal::IsTrue(expression)) { \
DeathTestAbort(::testing::internal::String::Format( \
"CHECK failed: File %s, line %d: %s", \
__FILE__, __LINE__, #expression)); \
} \
} while (::testing::internal::AlwaysFalse())
// This macro is similar to GTEST_DEATH_TEST_CHECK_, but it is meant for
// evaluating any system call that fulfills two conditions: it must return
// -1 on failure, and set errno to EINTR when it is interrupted and
// should be tried again. The macro expands to a loop that repeatedly
// evaluates the expression as long as it evaluates to -1 and sets
// errno to EINTR. If the expression evaluates to -1 but errno is
// something other than EINTR, DeathTestAbort is called.
#define GTEST_DEATH_TEST_CHECK_SYSCALL_(expression) \
do { \
int gtest_retval; \
do { \
gtest_retval = (expression); \
} while (gtest_retval == -1 && errno == EINTR); \
if (gtest_retval == -1) { \
DeathTestAbort(::testing::internal::String::Format( \
"CHECK failed: File %s, line %d: %s != -1", \
__FILE__, __LINE__, #expression)); \
} \
} while (::testing::internal::AlwaysFalse())
// Returns the message describing the last system error in errno.
String GetLastErrnoDescription() {
return String(errno == 0 ? "" : posix::StrError(errno));
}
// This is called from a death test parent process to read a failure
// message from the death test child process and log it with the FATAL
// severity. On Windows, the message is read from a pipe handle. On other
// platforms, it is read from a file descriptor.
static void FailFromInternalError(int fd) {
Message error;
char buffer[256];
int num_read;
do {
while ((num_read = posix::Read(fd, buffer, 255)) > 0) {
buffer[num_read] = '\0';
error << buffer;
}
} while (num_read == -1 && errno == EINTR);
if (num_read == 0) {
GTEST_LOG_(FATAL) << error.GetString();
} else {
const int last_error = errno;
GTEST_LOG_(FATAL) << "Error while reading death test internal: "
<< GetLastErrnoDescription() << " [" << last_error << "]";
}
}
// Death test constructor. Increments the running death test count
// for the current test.
DeathTest::DeathTest() {
TestInfo* const info = GetUnitTestImpl()->current_test_info();
if (info == NULL) {
DeathTestAbort("Cannot run a death test outside of a TEST or "
"TEST_F construct");
}
}
// Creates and returns a death test by dispatching to the current
// death test factory.
bool DeathTest::Create(const char* statement, const RE* regex,
const char* file, int line, DeathTest** test) {
return GetUnitTestImpl()->death_test_factory()->Create(
statement, regex, file, line, test);
}
const char* DeathTest::LastMessage() {
return last_death_test_message_.c_str();
}
void DeathTest::set_last_death_test_message(const String& message) {
last_death_test_message_ = message;
}
String DeathTest::last_death_test_message_;
// Provides cross platform implementation for some death functionality.
class DeathTestImpl : public DeathTest {
protected:
DeathTestImpl(const char* statement, const RE* regex)
: statement_(statement),
regex_(regex),
spawned_(false),
status_(-1),
outcome_(IN_PROGRESS),
read_fd_(-1),
write_fd_(-1) {}
// read_fd_ is expected to be closed and cleared by a derived class.
~DeathTestImpl() { GTEST_DEATH_TEST_CHECK_(read_fd_ == -1); }
void Abort(AbortReason reason);
virtual bool Passed(bool status_ok);
const char* statement() const { return statement_; }
const RE* regex() const { return regex_; }
bool spawned() const { return spawned_; }
void set_spawned(bool spawned) { spawned_ = spawned; }
int status() const { return status_; }
void set_status(int status) { status_ = status; }
DeathTestOutcome outcome() const { return outcome_; }
void set_outcome(DeathTestOutcome outcome) { outcome_ = outcome; }
int read_fd() const { return read_fd_; }
void set_read_fd(int fd) { read_fd_ = fd; }
int write_fd() const { return write_fd_; }
void set_write_fd(int fd) { write_fd_ = fd; }
// Called in the parent process only. Reads the result code of the death
// test child process via a pipe, interprets it to set the outcome_
// member, and closes read_fd_. Outputs diagnostics and terminates in
// case of unexpected codes.
void ReadAndInterpretStatusByte();
private:
// The textual content of the code this object is testing. This class
// doesn't own this string and should not attempt to delete it.
const char* const statement_;
// The regular expression which test output must match. DeathTestImpl
// doesn't own this object and should not attempt to delete it.
const RE* const regex_;
// True if the death test child process has been successfully spawned.
bool spawned_;
// The exit status of the child process.
int status_;
// How the death test concluded.
DeathTestOutcome outcome_;
// Descriptor to the read end of the pipe to the child process. It is
// always -1 in the child process. The child keeps its write end of the
// pipe in write_fd_.
int read_fd_;
// Descriptor to the child's write end of the pipe to the parent process.
// It is always -1 in the parent process. The parent keeps its end of the
// pipe in read_fd_.
int write_fd_;
};
// Called in the parent process only. Reads the result code of the death
// test child process via a pipe, interprets it to set the outcome_
// member, and closes read_fd_. Outputs diagnostics and terminates in
// case of unexpected codes.
void DeathTestImpl::ReadAndInterpretStatusByte() {
char flag;
int bytes_read;
// The read() here blocks until data is available (signifying the
// failure of the death test) or until the pipe is closed (signifying
// its success), so it's okay to call this in the parent before
// the child process has exited.
do {
bytes_read = posix::Read(read_fd(), &flag, 1);
} while (bytes_read == -1 && errno == EINTR);
if (bytes_read == 0) {
set_outcome(DIED);
} else if (bytes_read == 1) {
switch (flag) {
case kDeathTestReturned:
set_outcome(RETURNED);
break;
case kDeathTestLived:
set_outcome(LIVED);
break;
case kDeathTestInternalError:
FailFromInternalError(read_fd()); // Does not return.
break;
default:
GTEST_LOG_(FATAL) << "Death test child process reported "
<< "unexpected status byte ("
<< static_cast<unsigned int>(flag) << ")";
}
} else {
GTEST_LOG_(FATAL) << "Read from death test child process failed: "
<< GetLastErrnoDescription();
}
GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(read_fd()));
set_read_fd(-1);
}
// Signals that the death test code which should have exited, didn't.
// Should be called only in a death test child process.
// Writes a status byte to the child's status file descriptor, then
// calls _exit(1).
void DeathTestImpl::Abort(AbortReason reason) {
// The parent process considers the death test to be a failure if
// it finds any data in our pipe. So, here we write a single flag byte
// to the pipe, then exit.
const char status_ch =
reason == TEST_DID_NOT_DIE ? kDeathTestLived : kDeathTestReturned;
GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Write(write_fd(), &status_ch, 1));
GTEST_DEATH_TEST_CHECK_SYSCALL_(posix::Close(write_fd()));
_exit(1); // Exits w/o any normal exit hooks (we were supposed to crash)
}
// Assesses the success or failure of a death test, using both private
// members which have previously been set, and one argument:
//
// Private data members:
// outcome: An enumeration describing how the death test
// concluded: DIED, LIVED, or RETURNED. The death test fails
// in the latter two cases.
// status: The exit status of the child process. On *nix, it is in the
// in the format specified by wait(2). On Windows, this is the
// value supplied to the ExitProcess() API or a numeric code
// of the exception that terminated the program.
// regex: A regular expression object to be applied to
// the test's captured standard error output; the death test
// fails if it does not match.
//
// Argument:
// status_ok: true if exit_status is acceptable in the context of
// this particular death test, which fails if it is false
//
// Returns true iff all of the above conditions are met. Otherwise, the
// first failing condition, in the order given above, is the one that is
// reported. Also sets the last death test message string.
bool DeathTestImpl::Passed(bool status_ok) {
if (!spawned())
return false;
const String error_message = GetCapturedStderr();
bool success = false;
Message buffer;
buffer << "Death test: " << statement() << "\n";
switch (outcome()) {
case LIVED:
buffer << " Result: failed to die.\n"
<< " Error msg: " << error_message;
break;
case RETURNED:
buffer << " Result: illegal return in test statement.\n"
<< " Error msg: " << error_message;
break;
case DIED:
if (status_ok) {
const bool matched = RE::PartialMatch(error_message.c_str(), *regex());
if (matched) {
success = true;
} else {
buffer << " Result: died but not with expected error.\n"
<< " Expected: " << regex()->pattern() << "\n"
<< "Actual msg: " << error_message;
}
} else {
buffer << " Result: died but not with expected exit code:\n"
<< " " << ExitSummary(status()) << "\n";
}
break;
case IN_PROGRESS:
default:
GTEST_LOG_(FATAL)
<< "DeathTest::Passed somehow called before conclusion of test";
}
DeathTest::set_last_death_test_message(buffer.GetString());
return success;
}
#if GTEST_OS_WINDOWS
// WindowsDeathTest implements death tests on Windows. Due to the
// specifics of starting new processes on Windows, death tests there are
// always threadsafe, and Google Test considers the
// --gtest_death_test_style=fast setting to be equivalent to
// --gtest_death_test_style=threadsafe there.
//
// A few implementation notes: Like the Linux version, the Windows
// implementation uses pipes for child-to-parent communication. But due to
// the specifics of pipes on Windows, some extra steps are required:
//
// 1. The parent creates a communication pipe and stores handles to both
// ends of it.
// 2. The parent starts the child and provides it with the information
// necessary to acquire the handle to the write end of the pipe.
// 3. The child acquires the write end of the pipe and signals the parent
// using a Windows event.
// 4. Now the parent can release the write end of the pipe on its side. If
// this is done before step 3, the object's reference count goes down to
// 0 and it is destroyed, preventing the child from acquiring it. The
// parent now has to release it, or read operations on the read end of
// the pipe will not return when the child terminates.
// 5. The parent reads child's output through the pipe (outcome code and
// any possible error messages) from the pipe, and its stderr and then
// determines whether to fail the test.
//
// Note: to distinguish Win32 API calls from the local method and function
// calls, the former are explicitly resolved in the global namespace.
//
class WindowsDeathTest : public DeathTestImpl {
public:
WindowsDeathTest(const char* statement,
const RE* regex,
const char* file,
int line)
: DeathTestImpl(statement, regex), file_(file), line_(line) {}
// All of these virtual functions are inherited from DeathTest.
virtual int Wait();
virtual TestRole AssumeRole();
private:
// The name of the file in which the death test is located.
const char* const file_;
// The line number on which the death test is located.
const int line_;
// Handle to the write end of the pipe to the child process.
AutoHandle write_handle_;
// Child process handle.
AutoHandle child_handle_;
// Event the child process uses to signal the parent that it has
// acquired the handle to the write end of the pipe. After seeing this
// event the parent can release its own handles to make sure its
// ReadFile() calls return when the child terminates.
AutoHandle event_handle_;
};
// Waits for the child in a death test to exit, returning its exit
// status, or 0 if no child process exists. As a side effect, sets the
// outcome data member.
int WindowsDeathTest::Wait() {
if (!spawned())
return 0;
// Wait until the child either signals that it has acquired the write end
// of the pipe or it dies.
const HANDLE wait_handles[2] = { child_handle_.Get(), event_handle_.Get() };
switch (::WaitForMultipleObjects(2,
wait_handles,
FALSE, // Waits for any of the handles.
INFINITE)) {
case WAIT_OBJECT_0:
case WAIT_OBJECT_0 + 1:
break;
default:
GTEST_DEATH_TEST_CHECK_(false); // Should not get here.
}
// The child has acquired the write end of the pipe or exited.
// We release the handle on our side and continue.
write_handle_.Reset();
event_handle_.Reset();
ReadAndInterpretStatusByte();
// Waits for the child process to exit if it haven't already. This
// returns immediately if the child has already exited, regardless of
// whether previous calls to WaitForMultipleObjects synchronized on this
// handle or not.
GTEST_DEATH_TEST_CHECK_(
WAIT_OBJECT_0 == ::WaitForSingleObject(child_handle_.Get(),
INFINITE));
DWORD status;
GTEST_DEATH_TEST_CHECK_(::GetExitCodeProcess(child_handle_.Get(), &status)
!= FALSE);
child_handle_.Reset();
set_status(static_cast<int>(status));
return this->status();
}
// The AssumeRole process for a Windows death test. It creates a child
// process with the same executable as the current process to run the
// death test. The child process is given the --gtest_filter and
// --gtest_internal_run_death_test flags such that it knows to run the
// current death test only.
DeathTest::TestRole WindowsDeathTest::AssumeRole() {
const UnitTestImpl* const impl = GetUnitTestImpl();
const InternalRunDeathTestFlag* const flag =
impl->internal_run_death_test_flag();
const TestInfo* const info = impl->current_test_info();
const int death_test_index = info->result()->death_test_count();
if (flag != NULL) {
// ParseInternalRunDeathTestFlag() has performed all the necessary
// processing.
set_write_fd(flag->write_fd());
return EXECUTE_TEST;
}
// WindowsDeathTest uses an anonymous pipe to communicate results of
// a death test.
SECURITY_ATTRIBUTES handles_are_inheritable = {
sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
HANDLE read_handle, write_handle;
GTEST_DEATH_TEST_CHECK_(
::CreatePipe(&read_handle, &write_handle, &handles_are_inheritable,
0) // Default buffer size.
!= FALSE);
set_read_fd(::_open_osfhandle(reinterpret_cast<intptr_t>(read_handle),
O_RDONLY));
write_handle_.Reset(write_handle);
event_handle_.Reset(::CreateEvent(
&handles_are_inheritable,
TRUE, // The event will automatically reset to non-signaled state.
FALSE, // The initial state is non-signalled.
NULL)); // The even is unnamed.
GTEST_DEATH_TEST_CHECK_(event_handle_.Get() != NULL);
const String filter_flag = String::Format("--%s%s=%s.%s",
GTEST_FLAG_PREFIX_, kFilterFlag,
info->test_case_name(),
info->name());
const String internal_flag = String::Format(
"--%s%s=%s|%d|%d|%u|%Iu|%Iu",
GTEST_FLAG_PREFIX_,
kInternalRunDeathTestFlag,
file_, line_,
death_test_index,
static_cast<unsigned int>(::GetCurrentProcessId()),
// size_t has the same with as pointers on both 32-bit and 64-bit
// Windows platforms.
// See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
reinterpret_cast<size_t>(write_handle),
reinterpret_cast<size_t>(event_handle_.Get()));
char executable_path[_MAX_PATH + 1]; // NOLINT
GTEST_DEATH_TEST_CHECK_(
_MAX_PATH + 1 != ::GetModuleFileNameA(NULL,
executable_path,
_MAX_PATH));
String command_line = String::Format("%s %s \"%s\"",
::GetCommandLineA(),
filter_flag.c_str(),
internal_flag.c_str());
DeathTest::set_last_death_test_message("");
CaptureStderr();
// Flush the log buffers since the log streams are shared with the child.
FlushInfoLog();
// The child process will share the standard handles with the parent.
STARTUPINFOA startup_info;
memset(&startup_info, 0, sizeof(STARTUPINFO));
startup_info.dwFlags = STARTF_USESTDHANDLES;
startup_info.hStdInput = ::GetStdHandle(STD_INPUT_HANDLE);
startup_info.hStdOutput = ::GetStdHandle(STD_OUTPUT_HANDLE);
startup_info.hStdError = ::GetStdHandle(STD_ERROR_HANDLE);
PROCESS_INFORMATION process_info;
GTEST_DEATH_TEST_CHECK_(::CreateProcessA(
executable_path,
const_cast<char*>(command_line.c_str()),
NULL, // Retuned process handle is not inheritable.
NULL, // Retuned thread handle is not inheritable.
TRUE, // Child inherits all inheritable handles (for write_handle_).
0x0, // Default creation flags.
NULL, // Inherit the parent's environment.
UnitTest::GetInstance()->original_working_dir(),
&startup_info,
&process_info) != FALSE);
child_handle_.Reset(process_info.hProcess);
::CloseHandle(process_info.hThread);
set_spawned(true);
return OVERSEE_TEST;
}
#else // We are not on Windows.
// ForkingDeathTest provides implementations for most of the abstract
// methods of the DeathTest interface. Only the AssumeRole method is
// left undefined.
class ForkingDeathTest : public DeathTestImpl {
public:
ForkingDeathTest(const char* statement, const RE* regex);
// All of these virtual functions are inherited from DeathTest.
virtual int Wait();
protected:
void set_child_pid(pid_t child_pid) { child_pid_ = child_pid; }
private:
// PID of child process during death test; 0 in the child process itself.
pid_t child_pid_;
};
// Constructs a ForkingDeathTest.
ForkingDeathTest::ForkingDeathTest(const char* statement, const RE* regex)
: DeathTestImpl(statement, regex),
child_pid_(-1) {}
// Waits for the child in a death test to exit, returning its exit
// status, or 0 if no child process exists. As a side effect, sets the
// outcome data member.
int ForkingDeathTest::Wait() {
if (!spawned())
return 0;
ReadAndInterpretStatusByte();
int status;
GTEST_DEATH_TEST_CHECK_SYSCALL_(waitpid(child_pid_, &status, 0));
set_status(status);
return status;
}
// A concrete death test class that forks, then immediately runs the test
// in the child process.
class NoExecDeathTest : public ForkingDeathTest {
public:
NoExecDeathTest(const char* statement, const RE* regex) :
ForkingDeathTest(statement, regex) { }
virtual TestRole AssumeRole();
};
// The AssumeRole process for a fork-and-run death test. It implements a
// straightforward fork, with a simple pipe to transmit the status byte.
DeathTest::TestRole NoExecDeathTest::AssumeRole() {
const size_t thread_count = GetThreadCount();
if (thread_count != 1) {
GTEST_LOG_(WARNING) << DeathTestThreadWarning(thread_count);
}
int pipe_fd[2];
GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
DeathTest::set_last_death_test_message("");
CaptureStderr();
// When we fork the process below, the log file buffers are copied, but the
// file descriptors are shared. We flush all log files here so that closing
// the file descriptors in the child process doesn't throw off the
// synchronization between descriptors and buffers in the parent process.
// This is as close to the fork as possible to avoid a race condition in case
// there are multiple threads running before the death test, and another
// thread writes to the log file.
FlushInfoLog();
const pid_t child_pid = fork();
GTEST_DEATH_TEST_CHECK_(child_pid != -1);
set_child_pid(child_pid);
if (child_pid == 0) {
GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[0]));
set_write_fd(pipe_fd[1]);
// Redirects all logging to stderr in the child process to prevent
// concurrent writes to the log files. We capture stderr in the parent
// process and append the child process' output to a log.
LogToStderr();
// Event forwarding to the listeners of event listener API mush be shut
// down in death test subprocesses.
GetUnitTestImpl()->listeners()->SuppressEventForwarding();
return EXECUTE_TEST;
} else {
GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
set_read_fd(pipe_fd[0]);
set_spawned(true);
return OVERSEE_TEST;
}
}
// A concrete death test class that forks and re-executes the main
// program from the beginning, with command-line flags set that cause
// only this specific death test to be run.
class ExecDeathTest : public ForkingDeathTest {
public:
ExecDeathTest(const char* statement, const RE* regex,
const char* file, int line) :
ForkingDeathTest(statement, regex), file_(file), line_(line) { }
virtual TestRole AssumeRole();
private:
// The name of the file in which the death test is located.
const char* const file_;
// The line number on which the death test is located.
const int line_;
};
// Utility class for accumulating command-line arguments.
class Arguments {
public:
Arguments() {
args_.push_back(NULL);
}
~Arguments() {
for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
++i) {
free(*i);
}
}
void AddArgument(const char* argument) {
args_.insert(args_.end() - 1, posix::StrDup(argument));
}
template <typename Str>
void AddArguments(const ::std::vector<Str>& arguments) {
for (typename ::std::vector<Str>::const_iterator i = arguments.begin();
i != arguments.end();
++i) {
args_.insert(args_.end() - 1, posix::StrDup(i->c_str()));
}
}
char* const* Argv() {
return &args_[0];
}
private:
std::vector<char*> args_;
};
// A struct that encompasses the arguments to the child process of a
// threadsafe-style death test process.
struct ExecDeathTestArgs {
char* const* argv; // Command-line arguments for the child's call to exec
int close_fd; // File descriptor to close; the read end of a pipe
};
#if GTEST_OS_MAC
inline char** GetEnviron() {
// When Google Test is built as a framework on MacOS X, the environ variable
// is unavailable. Apple's documentation (man environ) recommends using
// _NSGetEnviron() instead.
return *_NSGetEnviron();
}
#else
// Some POSIX platforms expect you to declare environ. extern "C" makes
// it reside in the global namespace.
extern "C" char** environ;
inline char** GetEnviron() { return environ; }
#endif // GTEST_OS_MAC
// The main function for a threadsafe-style death test child process.
// This function is called in a clone()-ed process and thus must avoid
// any potentially unsafe operations like malloc or libc functions.
static int ExecDeathTestChildMain(void* child_arg) {
ExecDeathTestArgs* const args = static_cast<ExecDeathTestArgs*>(child_arg);
GTEST_DEATH_TEST_CHECK_SYSCALL_(close(args->close_fd));
// We need to execute the test program in the same environment where
// it was originally invoked. Therefore we change to the original
// working directory first.
const char* const original_dir =
UnitTest::GetInstance()->original_working_dir();
// We can safely call chdir() as it's a direct system call.
if (chdir(original_dir) != 0) {
DeathTestAbort(String::Format("chdir(\"%s\") failed: %s",
original_dir,
GetLastErrnoDescription().c_str()));
return EXIT_FAILURE;
}
// We can safely call execve() as it's a direct system call. We
// cannot use execvp() as it's a libc function and thus potentially
// unsafe. Since execve() doesn't search the PATH, the user must
// invoke the test program via a valid path that contains at least
// one path separator.
execve(args->argv[0], args->argv, GetEnviron());
DeathTestAbort(String::Format("execve(%s, ...) in %s failed: %s",
args->argv[0],
original_dir,
GetLastErrnoDescription().c_str()));
return EXIT_FAILURE;
}
// Two utility routines that together determine the direction the stack
// grows.
// This could be accomplished more elegantly by a single recursive
// function, but we want to guard against the unlikely possibility of
// a smart compiler optimizing the recursion away.
bool StackLowerThanAddress(const void* ptr) {
int dummy;
return &dummy < ptr;
}
bool StackGrowsDown() {
int dummy;
return StackLowerThanAddress(&dummy);
}
// A threadsafe implementation of fork(2) for threadsafe-style death tests
// that uses clone(2). It dies with an error message if anything goes
// wrong.
static pid_t ExecDeathTestFork(char* const* argv, int close_fd) {
ExecDeathTestArgs args = { argv, close_fd };
pid_t child_pid = -1;
#if GTEST_HAS_CLONE
const bool use_fork = GTEST_FLAG(death_test_use_fork);
if (!use_fork) {
static const bool stack_grows_down = StackGrowsDown();
const size_t stack_size = getpagesize();
// MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_PRIVATE, -1, 0);
GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
void* const stack_top =
static_cast<char*>(stack) + (stack_grows_down ? stack_size : 0);
child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);
GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
}
#else
const bool use_fork = true;
#endif // GTEST_HAS_CLONE
if (use_fork && (child_pid = fork()) == 0) {
ExecDeathTestChildMain(&args);
_exit(0);
}
GTEST_DEATH_TEST_CHECK_(child_pid != -1);
return child_pid;
}
// The AssumeRole process for a fork-and-exec death test. It re-executes the
// main program from the beginning, setting the --gtest_filter
// and --gtest_internal_run_death_test flags to cause only the current
// death test to be re-run.
DeathTest::TestRole ExecDeathTest::AssumeRole() {
const UnitTestImpl* const impl = GetUnitTestImpl();
const InternalRunDeathTestFlag* const flag =
impl->internal_run_death_test_flag();
const TestInfo* const info = impl->current_test_info();
const int death_test_index = info->result()->death_test_count();
if (flag != NULL) {
set_write_fd(flag->write_fd());
return EXECUTE_TEST;
}
int pipe_fd[2];
GTEST_DEATH_TEST_CHECK_(pipe(pipe_fd) != -1);
// Clear the close-on-exec flag on the write end of the pipe, lest
// it be closed when the child process does an exec:
GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
const String filter_flag =
String::Format("--%s%s=%s.%s",
GTEST_FLAG_PREFIX_, kFilterFlag,
info->test_case_name(), info->name());
const String internal_flag =
String::Format("--%s%s=%s|%d|%d|%d",
GTEST_FLAG_PREFIX_, kInternalRunDeathTestFlag,
file_, line_, death_test_index, pipe_fd[1]);
Arguments args;
args.AddArguments(GetArgvs());
args.AddArgument(filter_flag.c_str());
args.AddArgument(internal_flag.c_str());
DeathTest::set_last_death_test_message("");
CaptureStderr();
// See the comment in NoExecDeathTest::AssumeRole for why the next line
// is necessary.
FlushInfoLog();
const pid_t child_pid = ExecDeathTestFork(args.Argv(), pipe_fd[0]);
GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));
set_child_pid(child_pid);
set_read_fd(pipe_fd[0]);
set_spawned(true);
return OVERSEE_TEST;
}
#endif // !GTEST_OS_WINDOWS
// Creates a concrete DeathTest-derived class that depends on the
// --gtest_death_test_style flag, and sets the pointer pointed to
// by the "test" argument to its address. If the test should be
// skipped, sets that pointer to NULL. Returns true, unless the
// flag is set to an invalid value.
bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
const char* file, int line,
DeathTest** test) {
UnitTestImpl* const impl = GetUnitTestImpl();
const InternalRunDeathTestFlag* const flag =
impl->internal_run_death_test_flag();
const int death_test_index = impl->current_test_info()
->increment_death_test_count();
if (flag != NULL) {
if (death_test_index > flag->index()) {
DeathTest::set_last_death_test_message(String::Format(
"Death test count (%d) somehow exceeded expected maximum (%d)",
death_test_index, flag->index()));
return false;
}
if (!(flag->file() == file && flag->line() == line &&
flag->index() == death_test_index)) {
*test = NULL;
return true;
}
}
#if GTEST_OS_WINDOWS
if (GTEST_FLAG(death_test_style) == "threadsafe" ||
GTEST_FLAG(death_test_style) == "fast") {
*test = new WindowsDeathTest(statement, regex, file, line);
}
#else
if (GTEST_FLAG(death_test_style) == "threadsafe") {
*test = new ExecDeathTest(statement, regex, file, line);
} else if (GTEST_FLAG(death_test_style) == "fast") {
*test = new NoExecDeathTest(statement, regex);
}
#endif // GTEST_OS_WINDOWS
else { // NOLINT - this is more readable than unbalanced brackets inside #if.
DeathTest::set_last_death_test_message(String::Format(
"Unknown death test style \"%s\" encountered",
GTEST_FLAG(death_test_style).c_str()));
return false;
}
return true;
}
// Splits a given string on a given delimiter, populating a given
// vector with the fields. GTEST_HAS_DEATH_TEST implies that we have
// ::std::string, so we can use it here.
// TODO(vladl@google.com): Get rid of std::vector to be able to build on
// Visual C++ 7.1 with exceptions disabled.
static void SplitString(const ::std::string& str, char delimiter,
::std::vector< ::std::string>* dest) {
::std::vector< ::std::string> parsed;
::std::string::size_type pos = 0;
while (::testing::internal::AlwaysTrue()) {
const ::std::string::size_type colon = str.find(delimiter, pos);
if (colon == ::std::string::npos) {
parsed.push_back(str.substr(pos));
break;
} else {
parsed.push_back(str.substr(pos, colon - pos));
pos = colon + 1;
}
}
dest->swap(parsed);
}
#if GTEST_OS_WINDOWS
// Recreates the pipe and event handles from the provided parameters,
// signals the event, and returns a file descriptor wrapped around the pipe
// handle. This function is called in the child process only.
int GetStatusFileDescriptor(unsigned int parent_process_id,
size_t write_handle_as_size_t,
size_t event_handle_as_size_t) {
AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
FALSE, // Non-inheritable.
parent_process_id));
if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
DeathTestAbort(String::Format("Unable to open parent process %u",
parent_process_id));
}
// TODO(vladl@google.com): Replace the following check with a
// compile-time assertion when available.
GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));
const HANDLE write_handle =
reinterpret_cast<HANDLE>(write_handle_as_size_t);
HANDLE dup_write_handle;
// The newly initialized handle is accessible only in in the parent
// process. To obtain one accessible within the child, we need to use
// DuplicateHandle.
if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
::GetCurrentProcess(), &dup_write_handle,
0x0, // Requested privileges ignored since
// DUPLICATE_SAME_ACCESS is used.
FALSE, // Request non-inheritable handler.
DUPLICATE_SAME_ACCESS)) {
DeathTestAbort(String::Format(
"Unable to duplicate the pipe handle %Iu from the parent process %u",
write_handle_as_size_t, parent_process_id));
}
const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
HANDLE dup_event_handle;
if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
::GetCurrentProcess(), &dup_event_handle,
0x0,
FALSE,
DUPLICATE_SAME_ACCESS)) {
DeathTestAbort(String::Format(
"Unable to duplicate the event handle %Iu from the parent process %u",
event_handle_as_size_t, parent_process_id));
}
const int write_fd =
::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
if (write_fd == -1) {
DeathTestAbort(String::Format(
"Unable to convert pipe handle %Iu to a file descriptor",
write_handle_as_size_t));
}
// Signals the parent that the write end of the pipe has been acquired
// so the parent can release its own write end.
::SetEvent(dup_event_handle);
return write_fd;
}
#endif // GTEST_OS_WINDOWS
// Returns a newly created InternalRunDeathTestFlag object with fields
// initialized from the GTEST_FLAG(internal_run_death_test) flag if
// the flag is specified; otherwise returns NULL.
InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
if (GTEST_FLAG(internal_run_death_test) == "") return NULL;
// GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
// can use it here.
int line = -1;
int index = -1;
::std::vector< ::std::string> fields;
SplitString(GTEST_FLAG(internal_run_death_test).c_str(), '|', &fields);
int write_fd = -1;
#if GTEST_OS_WINDOWS
unsigned int parent_process_id = 0;
size_t write_handle_as_size_t = 0;
size_t event_handle_as_size_t = 0;
if (fields.size() != 6
|| !ParseNaturalNumber(fields[1], &line)
|| !ParseNaturalNumber(fields[2], &index)
|| !ParseNaturalNumber(fields[3], &parent_process_id)
|| !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
|| !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
DeathTestAbort(String::Format(
"Bad --gtest_internal_run_death_test flag: %s",
GTEST_FLAG(internal_run_death_test).c_str()));
}
write_fd = GetStatusFileDescriptor(parent_process_id,
write_handle_as_size_t,
event_handle_as_size_t);
#else
if (fields.size() != 4
|| !ParseNaturalNumber(fields[1], &line)
|| !ParseNaturalNumber(fields[2], &index)
|| !ParseNaturalNumber(fields[3], &write_fd)) {
DeathTestAbort(String::Format(
"Bad --gtest_internal_run_death_test flag: %s",
GTEST_FLAG(internal_run_death_test).c_str()));
}
#endif // GTEST_OS_WINDOWS
return new InternalRunDeathTestFlag(fields[0], line, index, write_fd);
}
} // namespace internal
#endif // GTEST_HAS_DEATH_TEST
} // namespace testing