#include <cstdio>
#include <cstdlib>
#include "unwind.h"

#define EXCEPTION_CLASS(a,b,c,d,e,f,g,h) \
	((static_cast<uint64_t>(a) << 56) +\
	 (static_cast<uint64_t>(b) << 48) +\
	 (static_cast<uint64_t>(c) << 40) +\
	 (static_cast<uint64_t>(d) << 32) +\
	 (static_cast<uint64_t>(e) << 24) +\
	 (static_cast<uint64_t>(f) << 16) +\
	 (static_cast<uint64_t>(g) << 8) +\
	 (static_cast<uint64_t>(h)))

// using ld --wrap=_Unwind_RaiseException hook feature
extern "C" _Unwind_Reason_Code __real__Unwind_RaiseException (_Unwind_Exception *e);
extern "C" _Unwind_Reason_Code __wrap__Unwind_RaiseException (_Unwind_Exception *e);

extern "C" _Unwind_Reason_Code __wrap__Unwind_RaiseException (_Unwind_Exception *e)
{
	// clobber exception class forcing libcxx own exceptions to be treated
	// as foreign exception within libcxx itself
	e->exception_class = EXCEPTION_CLASS('F','O','R','E','I','G','N','\0');
	__real__Unwind_RaiseException(e);
}

_Unwind_Exception global_e;

enum test_status {
	PENDING, PASSED, FAILED
};

const char test_status_str[][8] = {
	"PENDING", "PASSED", "FAILED"
};

test_status test1_status = PENDING;
test_status test2_status = PENDING;
test_status test3_status = PENDING;

void test2_exception_cleanup(_Unwind_Reason_Code code, _Unwind_Exception *e)
{
	fputs("(2) exception_cleanup called\n", stderr);
	if (e != &global_e) {
		fprintf(stderr, "(2) ERROR: unexpected ptr: expecting %p, got %p\n", &global_e, e);
		test2_status = FAILED;
	}
	if (test2_status == PENDING)
		test2_status = PASSED;
}

struct test3_exception
{
	static int counter;
	~test3_exception()
	{
		counter++;
		fputs("(3) exception dtor\n", stderr);
	}
};
int test3_exception::counter = 0;

int main()
{
	///////////////////////////////////////////////////////////////
	fputs("(1) foreign exception, exception_cleanup=nullptr\n", stderr);
	try
	{
		global_e.exception_class = 0;
		global_e.exception_cleanup = 0;
		__real__Unwind_RaiseException(&global_e);
	}
	catch (...)
	{
	}
	test1_status = PASSED;
	fputs("(1) PASS\n", stderr);

	///////////////////////////////////////////////////////////////
	fputs("(2) foreign exception, exception_cleanup present\n", stderr);
	try
	{
		global_e.exception_class = 0;
		global_e.exception_cleanup = test2_exception_cleanup;
		__real__Unwind_RaiseException(&global_e);
	}
	catch (...)
	{
	}
	fprintf(stderr, "(2) %s\n", test_status_str[test2_status]);

	///////////////////////////////////////////////////////////////
	fputs("(3) C++ exception in foreign environment\n", stderr);
	int counter_expected;
	try
	{
		// throw was rigged such that the runtime treats C++ exceptions
		// as foreign ones
		throw test3_exception();
	}
	catch (test3_exception&)
	{
		fputs("(3) ERROR: wrong catch\n", stderr);
		test3_status = FAILED;
	}
	catch (...)
	{
		fputs("(3) catch(...)\n", stderr);
		counter_expected = test3_exception::counter + 1;
		// one more dtor immediately after we leave catch
	}
	if (test3_status == PENDING && test3_exception::counter != counter_expected) {
		fputs("(3) ERROR: exception dtor didn't run\n", stderr);
		test3_status = FAILED;
	}
	if (test3_status == PENDING)
		test3_status = PASSED;
	fprintf(stderr, "(3) %s\n", test_status_str[test3_status]);

	///////////////////////////////////////////////////////////////
	if (test1_status == PASSED && test2_status == PASSED && test3_status == PASSED)
		return EXIT_SUCCESS;
	else
		return EXIT_FAILURE;
}