Function redirect

emmy_hook/src/emmy_hook.windows.cpp:303–415

}

void redirect(int port)
{
	HANDLE readStdPipe = NULL, writeStdPipe = NULL;

	SECURITY_ATTRIBUTES saAttr;
	saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
	saAttr.bInheritHandle = TRUE;
	saAttr.lpSecurityDescriptor = nullptr;

	CreatePipe(&readStdPipe, &writeStdPipe, &saAttr, 0);

	const auto oldStdout = _dup(_fileno(stdout));
	const auto oldStderr = _dup(_fileno(stderr));

	if (oldStdout == -1 || oldStderr == -1)
	{
		printf("stdout or stderr redirect error");
		if (oldStdout != -1)
		{
			_close(oldStdout);
		}
		if (oldStderr != -1)
		{
			_close(oldStderr);
		}

		return;
	}

	const auto stream = _open_osfhandle(reinterpret_cast<long>(writeStdPipe), 0);
	FILE* capture = nullptr;
	if (stream == -1)
	{
		printf("capture stream open fail");
		_dup2(oldStdout, _fileno(stdout));
		_dup2(oldStderr, _fileno(stderr));

		_close(oldStdout);
		_close(oldStderr);

		return;
	}
	capture = _fdopen(stream, "wt");

	// stdout now refers to file "capture" 
	if (_dup2(_fileno(capture), _fileno(stdout)) == -1)
	{
		printf("Can't _dup2 stdout to capture");

		_dup2(oldStdout, _fileno(stdout));
		_dup2(oldStderr, _fileno(stderr));

		_close(oldStdout);
		_close(oldStderr);

		return;
	}