// Copyright 2005, Google Inc.
// All rights reserved.
//
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// 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.
//
// Authors: wan@google.com (Zhanyong Wan), eefacm@gmail.com (Sean Mcafee)
//
// The Google C++ Testing Framework (Google Test)
//
// This header file defines internal utilities needed for implementing
// death tests.  They are subject to change without notice.

#ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_
#define GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_

#include "gtest/internal/gtest-internal.h"

#include <stdio.h>

namespace testing
{
namespace internal
{
GTEST_DECLARE_string_(internal_run_death_test);

// Names of the flags (needed for parsing Google Test flags).
const char kDeathTestStyleFlag[] = "death_test_style";
const char kDeathTestUseFork[] = "death_test_use_fork";
const char kInternalRunDeathTestFlag[] = "internal_run_death_test";

#if GTEST_HAS_DEATH_TEST

// DeathTest is a class that hides much of the complexity of the
// GTEST_DEATH_TEST_ macro.  It is abstract; its static Create method
// returns a concrete class that depends on the prevailing death test
// style, as defined by the --gtest_death_test_style and/or
// --gtest_internal_run_death_test flags.

// In describing the results of death tests, these terms are used with
// the corresponding definitions:
//
// exit status:  The integer exit information in the format specified
//               by wait(2)
// exit code:    The integer code passed to exit(3), _exit(2), or
//               returned from main()
class GTEST_API_ DeathTest
{
public:
	// Create returns false if there was an error determining the
	// appropriate action to take for the current death test; for example,
	// if the gtest_death_test_style flag is set to an invalid value.
	// The LastMessage method will return a more detailed message in that
	// case.  Otherwise, the DeathTest pointer pointed to by the "test"
	// argument is set.  If the death test should be skipped, the pointer
	// is set to NULL; otherwise, it is set to the address of a new concrete
	// DeathTest object that controls the execution of the current test.
	static bool Create(const char* statement, const RE* regex,
					   const char* file, int line, DeathTest** test);
	DeathTest();
	virtual ~DeathTest() {}

	// A helper class that aborts a death test when it's deleted.
	class ReturnSentinel
	{
	public:
		explicit ReturnSentinel(DeathTest* test) : test_(test) {}
		~ReturnSentinel() { test_->Abort(TEST_ENCOUNTERED_RETURN_STATEMENT); }

	private:
		DeathTest* const test_;
		GTEST_DISALLOW_COPY_AND_ASSIGN_(ReturnSentinel);
	} GTEST_ATTRIBUTE_UNUSED_;

	// An enumeration of possible roles that may be taken when a death
	// test is encountered.  EXECUTE means that the death test logic should
	// be executed immediately.  OVERSEE means that the program should prepare
	// the appropriate environment for a child process to execute the death
	// test, then wait for it to complete.
	enum TestRole
	{
		OVERSEE_TEST,
		EXECUTE_TEST
	};

	// An enumeration of the three reasons that a test might be aborted.
	enum AbortReason
	{
		TEST_ENCOUNTERED_RETURN_STATEMENT,
		TEST_THREW_EXCEPTION,
		TEST_DID_NOT_DIE
	};

	// Assumes one of the above roles.
	virtual TestRole AssumeRole() = 0;

	// Waits for the death test to finish and returns its status.
	virtual int Wait() = 0;

	// Returns true if the death test passed; that is, the test process
	// exited during the test, its exit status matches a user-supplied
	// predicate, and its stderr output matches a user-supplied regular
	// expression.
	// The user-supplied predicate may be a macro expression rather
	// than a function pointer or functor, or else Wait and Passed could
	// be combined.
	virtual bool Passed(bool exit_status_ok) = 0;

	// Signals that the death test did not die as expected.
	virtual void Abort(AbortReason reason) = 0;

	// Returns a human-readable outcome message regarding the outcome of
	// the last death test.
	static const char* LastMessage();

	static void set_last_death_test_message(const std::string& message);

private:
	// A string containing a description of the outcome of the last death test.
	static std::string last_death_test_message_;

	GTEST_DISALLOW_COPY_AND_ASSIGN_(DeathTest);
};

// Factory interface for death tests.  May be mocked out for testing.
class DeathTestFactory
{
public:
	virtual ~DeathTestFactory() {}
	virtual bool Create(const char* statement, const RE* regex,
						const char* file, int line, DeathTest** test) = 0;
};

// A concrete DeathTestFactory implementation for normal use.
class DefaultDeathTestFactory : public DeathTestFactory
{
public:
	virtual bool Create(const char* statement, const RE* regex,
						const char* file, int line, DeathTest** test);
};

// Returns true if exit_status describes a process that was terminated
// by a signal, or exited normally with a nonzero exit code.
GTEST_API_ bool ExitedUnsuccessfully(int exit_status);

// Traps C++ exceptions escaping statement and reports them as test
// failures. Note that trapping SEH exceptions is not implemented here.
#if GTEST_HAS_EXCEPTIONS
#define GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, death_test)               \
	try                                                                          \
	{                                                                            \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);               \
	}                                                                            \
	catch (const ::std::exception& gtest_exception)                              \
	{                                                                            \
		fprintf(                                                                 \
			stderr,                                                              \
			"\n%s: Caught std::exception-derived exception escaping the "        \
			"death test statement. Exception message: %s\n",                     \
			::testing::internal::FormatFileLocation(__FILE__, __LINE__).c_str(), \
			gtest_exception.what());                                             \
		fflush(stderr);                                                          \
		death_test->Abort(::testing::internal::DeathTest::TEST_THREW_EXCEPTION); \
	}                                                                            \
	catch (...)                                                                  \
	{                                                                            \
		death_test->Abort(::testing::internal::DeathTest::TEST_THREW_EXCEPTION); \
	}

#else
#define GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, death_test) \
	GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement)

#endif

// This macro is for implementing ASSERT_DEATH*, EXPECT_DEATH*,
// ASSERT_EXIT*, and EXPECT_EXIT*.
#define GTEST_DEATH_TEST_(statement, predicate, regex, fail)                           \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_                                                      \
	if (::testing::internal::AlwaysTrue())                                             \
	{                                                                                  \
		const ::testing::internal::RE& gtest_regex = (regex);                          \
		::testing::internal::DeathTest* gtest_dt;                                      \
		if (!::testing::internal::DeathTest::Create(#statement, &gtest_regex,          \
													__FILE__, __LINE__, &gtest_dt))    \
		{                                                                              \
			goto GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__);                          \
		}                                                                              \
		if (gtest_dt != NULL)                                                          \
		{                                                                              \
			::testing::internal::scoped_ptr< ::testing::internal::DeathTest>           \
				gtest_dt_ptr(gtest_dt);                                                \
			switch (gtest_dt->AssumeRole())                                            \
			{                                                                          \
				case ::testing::internal::DeathTest::OVERSEE_TEST:                     \
					if (!gtest_dt->Passed(predicate(gtest_dt->Wait())))                \
					{                                                                  \
						goto GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__);              \
					}                                                                  \
					break;                                                             \
				case ::testing::internal::DeathTest::EXECUTE_TEST:                     \
				{                                                                      \
					::testing::internal::DeathTest::ReturnSentinel                     \
						gtest_sentinel(gtest_dt);                                      \
					GTEST_EXECUTE_DEATH_TEST_STATEMENT_(statement, gtest_dt);          \
					gtest_dt->Abort(::testing::internal::DeathTest::TEST_DID_NOT_DIE); \
					break;                                                             \
				}                                                                      \
				default:                                                               \
					break;                                                             \
			}                                                                          \
		}                                                                              \
	}                                                                                  \
	else                                                                               \
		GTEST_CONCAT_TOKEN_(gtest_label_, __LINE__) : fail(::testing::internal::DeathTest::LastMessage())
// The symbol "fail" here expands to something into which a message
// can be streamed.

// This macro is for implementing ASSERT/EXPECT_DEBUG_DEATH when compiled in
// NDEBUG mode. In this case we need the statements to be executed, the regex is
// ignored, and the macro must accept a streamed message even though the message
// is never printed.
#define GTEST_EXECUTE_STATEMENT_(statement, regex)                 \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_                                  \
	if (::testing::internal::AlwaysTrue())                         \
	{                                                              \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement); \
	}                                                              \
	else                                                           \
		::testing::Message()

// A class representing the parsed contents of the
// --gtest_internal_run_death_test flag, as it existed when
// RUN_ALL_TESTS was called.
class InternalRunDeathTestFlag
{
public:
	InternalRunDeathTestFlag(const std::string& a_file,
							 int a_line,
							 int an_index,
							 int a_write_fd)
		: file_(a_file), line_(a_line), index_(an_index), write_fd_(a_write_fd) {}

	~InternalRunDeathTestFlag()
	{
		if (write_fd_ >= 0)
			posix::Close(write_fd_);
	}

	const std::string& file() const { return file_; }
	int line() const { return line_; }
	int index() const { return index_; }
	int write_fd() const { return write_fd_; }

private:
	std::string file_;
	int line_;
	int index_;
	int write_fd_;

	GTEST_DISALLOW_COPY_AND_ASSIGN_(InternalRunDeathTestFlag);
};

// 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();

#else  // GTEST_HAS_DEATH_TEST

// This macro is used for implementing macros such as
// EXPECT_DEATH_IF_SUPPORTED and ASSERT_DEATH_IF_SUPPORTED on systems where
// death tests are not supported. Those macros must compile on such systems
// iff EXPECT_DEATH and ASSERT_DEATH compile with the same parameters on
// systems that support death tests. This allows one to write such a macro
// on a system that does not support death tests and be sure that it will
// compile on a death-test supporting system.
//
// Parameters:
//   statement -  A statement that a macro such as EXPECT_DEATH would test
//                for program termination. This macro has to make sure this
//                statement is compiled but not executed, to ensure that
//                EXPECT_DEATH_IF_SUPPORTED compiles with a certain
//                parameter iff EXPECT_DEATH compiles with it.
//   regex     -  A regex that a macro such as EXPECT_DEATH would use to test
//                the output of statement.  This parameter has to be
//                compiled but not evaluated by this macro, to ensure that
//                this macro only accepts expressions that a macro such as
//                EXPECT_DEATH would accept.
//   terminator - Must be an empty statement for EXPECT_DEATH_IF_SUPPORTED
//                and a return statement for ASSERT_DEATH_IF_SUPPORTED.
//                This ensures that ASSERT_DEATH_IF_SUPPORTED will not
//                compile inside functions where ASSERT_DEATH doesn't
//                compile.
//
//  The branch that has an always false condition is used to ensure that
//  statement and regex are compiled (and thus syntactically correct) but
//  never executed. The unreachable code macro protects the terminator
//  statement from generating an 'unreachable code' warning in case
//  statement unconditionally returns or throws. The Message constructor at
//  the end allows the syntax of streaming additional messages into the
//  macro, for compilational compatibility with EXPECT_DEATH/ASSERT_DEATH.
#define GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, terminator) \
	GTEST_AMBIGUOUS_ELSE_BLOCKER_                                   \
	if (::testing::internal::AlwaysTrue())                          \
	{                                                               \
		GTEST_LOG_(WARNING)                                         \
			<< "Death tests are not supported on this platform.\n"  \
			<< "Statement '" #statement "' cannot be verified.";    \
	}                                                               \
	else if (::testing::internal::AlwaysFalse())                    \
	{                                                               \
		::testing::internal::RE::PartialMatch(".*", (regex));       \
		GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);  \
		terminator;                                                 \
	}                                                               \
	else                                                            \
		::testing::Message()

#endif  // GTEST_HAS_DEATH_TEST

}  // namespace internal
}  // namespace testing

#endif  // GTEST_INCLUDE_GTEST_INTERNAL_GTEST_DEATH_TEST_INTERNAL_H_
