C++ PyErr_Fetch函数代码示例

QString QgsPythonUtilsImpl::getTraceback()
{
#define TRACEBACK_FETCH_ERROR(what) {errMsg = what; goto done;}

  // acquire global interpreter lock to ensure we are in a consistent state
  PyGILState_STATE gstate;
  gstate = PyGILState_Ensure();

  QString errMsg;
  QString result;

  PyObject *modStringIO = NULL;
  PyObject *modTB = NULL;
  PyObject *obStringIO = NULL;
  PyObject *obResult = NULL;

  PyObject *type, *value, *traceback;

  PyErr_Fetch( &type, &value, &traceback );
  PyErr_NormalizeException( &type, &value, &traceback );

  modStringIO = PyImport_ImportModule( "cStringIO" );
  if ( modStringIO == NULL )
    TRACEBACK_FETCH_ERROR( "can't import cStringIO" );

  obStringIO = PyObject_CallMethod( modStringIO, ( char* ) "StringIO", NULL );

  /* Construct a cStringIO object */
  if ( obStringIO == NULL )
    TRACEBACK_FETCH_ERROR( "cStringIO.StringIO() failed" );

  modTB = PyImport_ImportModule( "traceback" );
  if ( modTB == NULL )
    TRACEBACK_FETCH_ERROR( "can't import traceback" );

  obResult = PyObject_CallMethod( modTB, ( char* ) "print_exception",
                                  ( char* ) "OOOOO",
                                  type, value ? value : Py_None,
                                  traceback ? traceback : Py_None,
                                  Py_None,
                                  obStringIO );

  if ( obResult == NULL )
    TRACEBACK_FETCH_ERROR( "traceback.print_exception() failed" );
  Py_DECREF( obResult );

  obResult = PyObject_CallMethod( obStringIO, ( char* ) "getvalue", NULL );
  if ( obResult == NULL )
    TRACEBACK_FETCH_ERROR( "getvalue() failed." );

  /* And it should be a string all ready to go - duplicate it. */
  if ( !PyString_Check( obResult ) )
    TRACEBACK_FETCH_ERROR( "getvalue() did not return a string" );

  result = PyString_AsString( obResult );

done:

  // All finished - first see if we encountered an error
  if ( result.isEmpty() && !errMsg.isEmpty() )
  {
    result = errMsg;
  }

  Py_XDECREF( modStringIO );
  Py_XDECREF( modTB );
  Py_XDECREF( obStringIO );
  Py_XDECREF( obResult );
  Py_XDECREF( value );
  Py_XDECREF( traceback );
  Py_XDECREF( type );

  // we are done calling python API, release global interpreter lock
  PyGILState_Release( gstate );

  return result;
}

/* This function is called by the tp_dealloc handler to clear weak references.
 *
 * This iterates through the weak references for 'object' and calls callbacks
 * for those references which have one.  It returns when all callbacks have
 * been attempted.
 */
void
PyObject_ClearWeakRefs(PyObject *object)
{
    PyWeakReference **list;

    if (object == NULL
        || !PyType_SUPPORTS_WEAKREFS(Py_TYPE(object))
        || object->ob_refcnt != 0) {
        PyErr_BadInternalCall();
        return;
    }
    list = GET_WEAKREFS_LISTPTR(object);
    /* Remove the callback-less basic and proxy references */
    if (*list != NULL && (*list)->wr_callback == NULL) {
        clear_weakref(*list);
        if (*list != NULL && (*list)->wr_callback == NULL)
            clear_weakref(*list);
    }
    if (*list != NULL) {
        PyWeakReference *current = *list;
        Py_ssize_t count = _PyWeakref_GetWeakrefCount(current);
        PyObject *err_type, *err_value, *err_tb;

        PyErr_Fetch(&err_type, &err_value, &err_tb);
        if (count == 1) {
            PyObject *callback = current->wr_callback;

            current->wr_callback = NULL;
            clear_weakref(current);
            if (callback != NULL) {
                if (current->ob_refcnt > 0)
                    handle_callback(current, callback);
                Py_DECREF(callback);
            }
        }
        else {
            PyObject *tuple;
            Py_ssize_t i = 0;

            tuple = PyTuple_New(count * 2);
            if (tuple == NULL) {
                _PyErr_ReplaceException(err_type, err_value, err_tb);
                return;
            }

            for (i = 0; i < count; ++i) {
                PyWeakReference *next = current->wr_next;

                if (current->ob_refcnt > 0)
                {
                    Py_INCREF(current);
                    PyTuple_SET_ITEM(tuple, i * 2, (PyObject *) current);
                    PyTuple_SET_ITEM(tuple, i * 2 + 1, current->wr_callback);
                }
                else {
                    Py_DECREF(current->wr_callback);
                }
                current->wr_callback = NULL;
                clear_weakref(current);
                current = next;
            }
            for (i = 0; i < count; ++i) {
                PyObject *callback = PyTuple_GET_ITEM(tuple, i * 2 + 1);

                /* The tuple may have slots left to NULL */
                if (callback != NULL) {
                    PyObject *item = PyTuple_GET_ITEM(tuple, i * 2);
                    handle_callback((PyWeakReference *)item, callback);
                }
            }
            Py_DECREF(tuple);
        }
        assert(!PyErr_Occurred());
        PyErr_Restore(err_type, err_value, err_tb);
    }
}

static int GREENLET_NOINLINE(g_initialstub)(void* mark)
{
	int err;
	PyObject *o, *run;
	PyObject *exc, *val, *tb;
	PyObject *run_info;
	PyGreenlet* self = ts_target;
	PyObject* args = ts_passaround_args;
	PyObject* kwargs = ts_passaround_kwargs;

	/* save exception in case getattr clears it */
	PyErr_Fetch(&exc, &val, &tb);
	/* self.run is the object to call in the new greenlet */
	run = PyObject_GetAttrString((PyObject*) self, "run");
	if (run == NULL) {
		Py_XDECREF(exc);
		Py_XDECREF(val);
		Py_XDECREF(tb);
		return -1;
	}
	/* restore saved exception */
	PyErr_Restore(exc, val, tb);

	/* recheck the state in case getattr caused thread switches */
	if (!STATE_OK) {
		Py_DECREF(run);
		return -1;
	}

	/* recheck run_info in case greenlet reparented anywhere above */
	run_info = green_statedict(self);
	if (run_info == NULL || run_info != ts_current->run_info) {
		Py_DECREF(run);
		PyErr_SetString(PyExc_GreenletError, run_info
		                ? "cannot switch to a different thread"
		                : "cannot switch to a garbage collected greenlet");
		return -1;
	}

	/* by the time we got here another start could happen elsewhere,
	 * that means it should now be a regular switch
	 */
	if (PyGreenlet_STARTED(self)) {
		Py_DECREF(run);
		ts_passaround_args = args;
		ts_passaround_kwargs = kwargs;
		return 1;
	}

	/* start the greenlet */
	self->stack_start = NULL;
	self->stack_stop = (char*) mark;
	if (ts_current->stack_start == NULL) {
		/* ts_current is dying */
		self->stack_prev = ts_current->stack_prev;
	}
	else {
		self->stack_prev = ts_current;
	}
	self->top_frame = NULL;
	self->exc_type = NULL;
	self->exc_value = NULL;
	self->exc_traceback = NULL;
	self->recursion_depth = PyThreadState_GET()->recursion_depth;

	/* restore arguments in case they are clobbered */
	ts_target = self;
	ts_passaround_args = args;
	ts_passaround_kwargs = kwargs;

	/* perform the initial switch */
	err = g_switchstack();

	/* returns twice!
	   The 1st time with err=1: we are in the new greenlet
	   The 2nd time with err=0: back in the caller's greenlet
	*/
	if (err == 1) {
		/* in the new greenlet */
		PyGreenlet* origin;
#if GREENLET_USE_TRACING
		PyObject* tracefunc;
#endif
		PyObject* result;
		PyGreenlet* parent;
		self->stack_start = (char*) 1;  /* running */

		/* grab origin while we still can */
		origin = ts_origin;
		ts_origin = NULL;

		/* now use run_info to store the statedict */
		o = self->run_info;
		self->run_info = green_statedict(self->parent);
		Py_INCREF(self->run_info);
		Py_XDECREF(o);

#if GREENLET_USE_TRACING
		if ((tracefunc = PyDict_GetItem(self->run_info, ts_tracekey)) != NULL) {
			Py_INCREF(tracefunc);
//.........这里部分代码省略.........

/* Reads a buffer from the file object
 * Make sure to hold the GIL state before calling this function
 * Returns the number of bytes read if successful, or -1 on error
 */
ssize_t pyewf_file_object_read_buffer(
         PyObject *file_object,
         uint8_t *buffer,
         size_t size,
         libcerror_error_t **error )
{
	PyObject *argument_size       = NULL;
	PyObject *exception_string    = NULL;
	PyObject *exception_traceback = NULL;
	PyObject *exception_type      = NULL;
	PyObject *exception_value     = NULL;
	PyObject *method_name         = NULL;
	PyObject *method_result       = NULL;
	char *error_string            = NULL;
	char *safe_buffer             = NULL;
	static char *function         = "pyewf_file_object_read_buffer";
	Py_ssize_t safe_read_count    = 0;
	ssize_t read_count            = 0;
	int result                    = 0;

	if( file_object == NULL )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
		 "%s: invalid file object.",
		 function );

		return( -1 );
	}
	if( buffer == NULL )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
		 "%s: invalid buffer.",
		 function );

		return( -1 );
	}
	if( size > (size_t) SSIZE_MAX )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,
		 "%s: invalid size value exceeds maximum.",
		 function );

		return( -1 );
	}
	if( size > 0 )
	{
		method_name = PyString_FromString(
			       "read" );

		argument_size = PyLong_FromSize_t(
				 size );

		PyErr_Clear();

		method_result = PyObject_CallMethodObjArgs(
				 file_object,
				 method_name,
				 argument_size,
				 NULL );

		if( PyErr_Occurred() )
		{
			PyErr_Fetch(
			 &exception_type,
			 &exception_value,
			 &exception_traceback );

			exception_string = PyObject_Repr(
					    exception_value );

			error_string = PyString_AsString(
					exception_string );

			if( error_string != NULL )
			{
				libcerror_error_set(
				 error,
				 LIBCERROR_ERROR_DOMAIN_IO,
				 LIBCERROR_IO_ERROR_READ_FAILED,
				 "%s: unable to read from file object with error: %s.",
				 function,
				 error_string );
			}
			else
			{
				libcerror_error_set(
				 error,
//.........这里部分代码省略.........

/* Seeks a certain offset within the file object
 * Make sure to hold the GIL state before calling this function
 * Returns 1 if successful or -1 on error
 */
int pyewf_file_object_seek_offset(
     PyObject *file_object,
     off64_t offset,
     int whence,
     libcerror_error_t **error )
{
	PyObject *argument_offset     = NULL;
	PyObject *argument_whence     = NULL;
	PyObject *exception_string    = NULL;
	PyObject *exception_traceback = NULL;
	PyObject *exception_type      = NULL;
	PyObject *exception_value     = NULL;
	PyObject *method_name         = NULL;
	PyObject *method_result       = NULL;
	char *error_string            = NULL;
	static char *function         = "pyewf_file_object_seek_offset";

	if( file_object == NULL )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
		 "%s: invalid file object.",
		 function );

		return( -1 );
	}
#if defined( HAVE_LONG_LONG )
	if( offset > (off64_t) INT64_MAX )
#else
	if( offset > (off64_t) LONG_MAX )
#endif
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,
		 "%s: invalid offset value exceeds maximum.",
		 function );

		return( -1 );
	}
	if( ( whence != SEEK_CUR )
	 && ( whence != SEEK_END )
	 && ( whence != SEEK_SET ) )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_UNSUPPORTED_VALUE,
		 "%s: unsupported whence.",
		 function );

		return( -1 );
	}
	method_name = PyString_FromString(
	               "seek" );

#if defined( HAVE_LONG_LONG )
	argument_offset = PyLong_FromLongLong(
	                   (PY_LONG_LONG) offset );
#else
	argument_offset = PyLong_FromLongLong(
	                   (long) offset );
#endif
	argument_whence = PyInt_FromLong(
	                   (long) whence );

	PyErr_Clear();

	method_result = PyObject_CallMethodObjArgs(
	                 file_object,
	                 method_name,
	                 argument_offset,
	                 argument_whence,
	                 NULL );

	if( PyErr_Occurred() )
	{
		PyErr_Fetch(
		 &exception_type,
		 &exception_value,
		 &exception_traceback );

		exception_string = PyObject_Repr(
		                    exception_value );

		error_string = PyString_AsString(
		                exception_string );

		if( error_string != NULL )
		{
			libcerror_error_set(
			 error,
			 LIBCERROR_ERROR_DOMAIN_IO,
//.........这里部分代码省略.........

// Call a single slot and return the result.
PyObject *PyQtSlot::call(PyObject *callable, PyObject *args) const
{
    PyObject *sa, *oxtype, *oxvalue, *oxtb;

    // Keep some compilers quiet.
    oxtype = oxvalue = oxtb = 0;

    // We make repeated attempts to call a slot.  If we work out that it failed
    // because of an immediate type error we try again with one less argument.
    // We keep going until we run out of arguments to drop.  This emulates the
    // Qt ability of the slot to accept fewer arguments than a signal provides.
    sa = args;
    Py_INCREF(sa);

    for (;;)
    {
        PyObject *nsa, *xtype, *xvalue, *xtb, *res;

        if ((res = PyEval_CallObject(callable, sa)) != NULL)
        {
            // Remove any previous exception.

            if (sa != args)
            {
                Py_XDECREF(oxtype);
                Py_XDECREF(oxvalue);
                Py_XDECREF(oxtb);
                PyErr_Clear();
            }

            Py_DECREF(sa);

            return res;
        }

        // Get the exception.
        PyErr_Fetch(&xtype, &xvalue, &xtb);

        // See if it is unacceptable.  An acceptable failure is a type error
        // with no traceback - so long as we can still reduce the number of
        // arguments and try again.
        if (!PyErr_GivenExceptionMatches(xtype, PyExc_TypeError) || xtb ||
            PyTuple_Size(sa) == 0)
        {
            // If there is a traceback then we must have called the slot and
            // the exception was later on - so report the exception as is.
            if (xtb)
            {
                if (sa != args)
                {
                    Py_XDECREF(oxtype);
                    Py_XDECREF(oxvalue);
                    Py_XDECREF(oxtb);
                }

                PyErr_Restore(xtype,xvalue,xtb);
            }
            else if (sa == args)
            {
                PyErr_Restore(xtype, xvalue, xtb);
            }
            else
            {
                // Discard the latest exception and restore the original one.
                Py_XDECREF(xtype);
                Py_XDECREF(xvalue);
                Py_XDECREF(xtb);

                PyErr_Restore(oxtype, oxvalue, oxtb);
            }

            break;
        }

        // If this is the first attempt, save the exception.
        if (sa == args)
        {
            oxtype = xtype;
            oxvalue = xvalue;
            oxtb = xtb;
        }
        else
        {
            Py_XDECREF(xtype);
            Py_XDECREF(xvalue);
            Py_XDECREF(xtb);
        }

        // Create the new argument tuple.
        if ((nsa = PyTuple_GetSlice(sa, 0, PyTuple_Size(sa) - 1)) == NULL)
        {
            // Tidy up.
            Py_XDECREF(oxtype);
            Py_XDECREF(oxvalue);
            Py_XDECREF(oxtb);

            break;
        }

//.........这里部分代码省略.........

/* Retrieves the current offset within the file object
 * Make sure to hold the GIL state before calling this function
 * Returns 1 if successful or -1 on error
 */
int pyewf_file_object_get_offset(
     PyObject *file_object,
     off64_t *offset,
     libcerror_error_t **error )
{
	PyObject *exception_string    = NULL;
	PyObject *exception_traceback = NULL;
	PyObject *exception_type      = NULL;
	PyObject *exception_value     = NULL;
	PyObject *method_name         = NULL;
	PyObject *method_result       = NULL;
	char *error_string            = NULL;
	static char *function         = "pyewf_file_object_get_offset";
	int result                    = 0;

	if( file_object == NULL )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
		 "%s: invalid file object.",
		 function );

		return( -1 );
	}
	if( offset == NULL )
	{
		libcerror_error_set(
		 error,
		 LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
		 LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
		 "%s: invalid offset.",
		 function );

		return( -1 );
	}
	method_name = PyString_FromString(
	               "get_offset" );

	PyErr_Clear();

	/* Determine if the file object has the get_offset method
	 */
	result = PyObject_HasAttr(
	          file_object,
	          method_name );

	if( result == 0 )
	{
		Py_DecRef(
		 method_name );

		/* Fall back to the tell method
		 */
		method_name = PyString_FromString(
		               "tell" );
	}
	PyErr_Clear();

	method_result = PyObject_CallMethodObjArgs(
	                 file_object,
	                 method_name,
	                 NULL );

	if( PyErr_Occurred() )
	{
		PyErr_Fetch(
		 &exception_type,
		 &exception_value,
		 &exception_traceback );

		exception_string = PyObject_Repr(
		                    exception_value );

		error_string = PyString_AsString(
		                exception_string );

		if( error_string != NULL )
		{
			libcerror_error_set(
			 error,
			 LIBCERROR_ERROR_DOMAIN_RUNTIME,
			 LIBCERROR_RUNTIME_ERROR_GET_FAILED,
			 "%s: unable to retrieve current offset in file object with error: %s.",
			 function,
			 error_string );
		}
		else
		{
			libcerror_error_set(
			 error,
			 LIBCERROR_ERROR_DOMAIN_RUNTIME,
			 LIBCERROR_RUNTIME_ERROR_GET_FAILED,
			 "%s: unable to retrieve current offset in file object.",
			 function );
//.........这里部分代码省略.........

static int
profiler_callback(PyObject *self, PyFrameObject *frame, int what,
                  PyObject *arg)
{
    ProfilerObject *pObj = (ProfilerObject*)self;
    {
        /* keep error state, see ptrace_enter_call above.
         * We could keep this more focused, only really needed
         * when calling a user time function, and initializing
         * a user object
         */
        PyObject *et, *ev, *tb;
        PyErr_Fetch(&et, &ev, &tb);
        pObj->currentTime = CALL_TIMER(pObj);
        SelectStack(pObj);
        PyErr_Restore(et, ev, tb);
    }
    if (pObj->currentProfilerStack == NULL)
        return 0;

    switch (what) {

    /* the 'frame' of a called function is about to start its execution */
    case PyTrace_CALL:
        ptrace_enter_call(self, (void *)frame->f_code,
                                (PyObject *)frame->f_code);
        break;

    /* the 'frame' of a called function is about to finish
       (either normally or with an exception) */
    case PyTrace_RETURN:
        ptrace_leave_call(self, (void *)frame->f_code);
        break;

    /* case PyTrace_EXCEPTION:
        If the exception results in the function exiting, a
        PyTrace_RETURN event will be generated, so we don't need to
        handle it. */

#ifdef PyTrace_C_CALL   /* not defined in Python <= 2.3 */
    /* the Python function 'frame' is issuing a call to the built-in
       function 'arg' */
    case PyTrace_C_CALL:
        if ((((ProfilerObject *)self)->flags & POF_BUILTINS)
            && PyCFunction_Check(arg)) {
            ptrace_enter_call(self,
                              ((PyCFunctionObject *)arg)->m_ml,
                              arg);
        }
        break;

    /* the call to the built-in function 'arg' is returning into its
       caller 'frame' */
    case PyTrace_C_RETURN:              /* ...normally */
    case PyTrace_C_EXCEPTION:           /* ...with an exception set */
        if ((((ProfilerObject *)self)->flags & POF_BUILTINS)
            && PyCFunction_Check(arg)) {
            ptrace_leave_call(self,
                              ((PyCFunctionObject *)arg)->m_ml);
        }
        break;
#endif

    default:
        break;
    }
    return 0;
}

bool PythonScript::execute(TWScriptAPI *tw) const
{
    PyObject * tmp;

    // Load the script
    QFile scriptFile(m_Filename);
    if (!scriptFile.open(QIODevice::ReadOnly)) {
        // handle error
        return false;
    }
    QString contents = m_Codec->toUnicode(scriptFile.readAll());
    scriptFile.close();

    // Python seems to require Unix style line endings
    if (contents.contains("\r"))
        contents.replace(QRegExp("\r\n?"), "\n");

    // Create a separate sub-interpreter for this script
    PyThreadState* interpreter = Py_NewInterpreter();

    // Register the types
    if (!registerPythonTypes(tw->GetResult())) {
        Py_EndInterpreter(interpreter);
        return false;
    }

    pyQObject *TW;

    TW = (pyQObject*)QObjectToPython(tw);
    if (!TW) {
        tw->SetResult(tr("Could not create TW"));
        Py_EndInterpreter(interpreter);
        return false;
    }

    // Run the script
    PyObject * globals, * locals;
    globals = PyDict_New();
    locals = PyDict_New();

    // Create a dictionary of global variables
    // without the __builtins__ module, nothing would work!
    PyDict_SetItemString(globals, "__builtins__", PyEval_GetBuiltins());
    PyDict_SetItemString(globals, "TW", (PyObject*)TW);

    PyObject * ret = NULL;

    if (globals && locals)
        ret = PyRun_String(qPrintable(contents), Py_file_input, globals, locals);

    Py_XDECREF(globals);
    Py_XDECREF(locals);
    Py_XDECREF(ret);
    Py_XDECREF(TW);

    // Check for exceptions
    if (PyErr_Occurred()) {
        PyObject * errType, * errValue, * errTraceback;
        PyErr_Fetch(&errType, &errValue, &errTraceback);

        tmp = PyObject_Str(errValue);
        QString errString;
        if (!asQString(tmp, errString)) {
            Py_XDECREF(tmp);
            tw->SetResult(tr("Unknown error"));
            return false;
        }
        Py_XDECREF(tmp);
        tw->SetResult(errString);

        /////////////////////DEBUG
        // This prints the python error in the usual python way to stdout
        // Simply comment this block to prevent this behavior
        Py_XINCREF(errType);
        Py_XINCREF(errValue);
        Py_XINCREF(errTraceback);
        PyErr_Restore(errType, errValue, errTraceback);
        PyErr_Print();
        /////////////////////DEBUG

        Py_XDECREF(errType);
        Py_XDECREF(errValue);
        Py_XDECREF(errTraceback);

        Py_EndInterpreter(interpreter);
        return false;
    }

    // Finish
    Py_EndInterpreter(interpreter);
    return true;
}

// Format the current Python exception as a string.
// Let Python do the work for us; call traceback.format_exception()
std::string formatPythonException() {
    if (!PyErr_Occurred()) {
        return "<no error?>";
    }

    // Retrieve Python exception and "normalize" (the docs are unclear but
    // they say you should do it :) )
    PyObject* exceptionObj;
    PyObject* valueObj;
    PyObject* tracebackObj;
    PyErr_Fetch(&exceptionObj, &valueObj, &tracebackObj);
    DCHECK(exceptionObj);
    PyErr_NormalizeException(&exceptionObj, &valueObj, &tracebackObj);

    PyObjectHandle exception(exceptionObj);
    PyObjectHandle value(valueObj);
    PyObjectHandle traceback(tracebackObj);

    // value and traceback may be null
    if (!value) {
        value.reset(PyObjectHandle::INCREF, Py_None);
    }
    if (!traceback) {
        traceback.reset(PyObjectHandle::INCREF, Py_None);
    }

    PyObjectHandle tbModule(PyImport_ImportModule("traceback"));
    if (!tbModule) {
        return "<import traceback failed>";
    }

    PyObject* tbDict = PyModule_GetDict(tbModule.get());  // borrowed
    if (!tbDict) {
        return "<no dict in traceback module>";
    }

    // borrowed
    PyObject* formatFunc = PyDict_GetItemString(tbDict, "format_exception");
    if (!formatFunc) {
        return "<no format_exception in traceback module>";
    }

    PyObjectHandle formatted(PyObject_CallFunction(
                                 formatFunc, const_cast<char*>("OOO"), exception.get(), value.get(),
                                 traceback.get()));
    if (!formatted) {
        return "<traceback.format_exception error>";
    }

    // format_exception returns a list of strings that should be concatenated.
    // Well then, let's do that.

    if (!PyList_Check(formatted.get())) {
        return "<traceback.format_exception didn't return a list>";
    }

    std::string out;
    for (Py_ssize_t i = 0; i < PyList_GET_SIZE(formatted.get()); ++i) {
        PyObject* obj = PyList_GET_ITEM(formatted.get(), i);  // borrowed
        char* data;
        Py_ssize_t len;
        if (PyString_AsStringAndSize(obj, &data, &len) == -1) {
            return "<traceback.format_exception member not a string>";
        }
        out.append(data, len);
    }

    return out;
}

/* Fetches an error
 */
void VARARGS(
      pyesedb_error_fetch,
      libcerror_error_t **error,
      int error_domain,
      int error_code,
      const char *,
      format_string )
{
	va_list argument_list;

	char error_string[ PYESEDB_ERROR_STRING_SIZE ];

        PyObject *exception_traceback = NULL;
        PyObject *exception_type      = NULL;
        PyObject *exception_value     = NULL;
        PyObject *string_object       = NULL;
	static char *function         = "pyesedb_error_fetch";
	char *exception_string        = NULL;
	size_t error_string_length    = 0;
	int print_count               = 0;

#if PY_MAJOR_VERSION >= 3
	PyObject *utf8_string_object  = NULL;
#endif

	if( format_string == NULL )
	{
		PyErr_Format(
		 PyExc_ValueError,
		 "%s: missing format string.",
		 function );

		return;
	}
	VASTART(
	 argument_list,
	 const char *,
	 format_string );

	print_count = PyOS_vsnprintf(
	               error_string,
	               PYESEDB_ERROR_STRING_SIZE,
	               format_string,
	               argument_list );

	VAEND(
	 argument_list );

	if( print_count < 0 )
	{
		PyErr_Format(
		 PyExc_ValueError,
		 "%s: unable to format error string.",
		 function );

		return;
	}
	error_string_length = libcstring_narrow_string_length(
	                       error_string );

	if( ( error_string_length >= 1 )
	 && ( error_string[ error_string_length - 1 ] == '.' ) )
	{
		error_string[ error_string_length - 1 ] = 0;
	}
	PyErr_Fetch(
	 &exception_type,
	 &exception_value,
	 &exception_traceback );

	string_object = PyObject_Repr(
	                 exception_value );

#if PY_MAJOR_VERSION >= 3
	utf8_string_object = PyUnicode_AsUTF8String(
	                      string_object );

	if( utf8_string_object != NULL )
	{
		exception_string = PyBytes_AsString(
		                    utf8_string_object );
	}
#else
	exception_string = PyString_AsString(
	                    string_object );
#endif
	if( exception_string != NULL )
	{
		libcerror_error_set(
		 error,
		 error_domain,
		 error_code,
		 "%s with error: %s.",
		 error_string,
		 exception_string );
	}
	else
	{
//.........这里部分代码省略.........

static varobj_item *
py_varobj_iter_next (struct varobj_iter *self)
{
  struct py_varobj_iter *t = (struct py_varobj_iter *) self;
  struct cleanup *back_to;
  PyObject *item;
  PyObject *py_v;
  varobj_item *vitem;
  const char *name = NULL;

  if (!gdb_python_initialized)
    return NULL;

  back_to = varobj_ensure_python_env (self->var);

  item = PyIter_Next (t->iter);

  if (item == NULL)
    {
      /* Normal end of iteration.  */
      if (!PyErr_Occurred ())
	return NULL;

      /* If we got a memory error, just use the text as the item.  */
      if (PyErr_ExceptionMatches (gdbpy_gdb_memory_error))
	{
	  PyObject *type, *value, *trace;
	  char *name_str, *value_str;

	  PyErr_Fetch (&type, &value, &trace);
	  value_str = gdbpy_exception_to_string (type, value);
	  Py_XDECREF (type);
	  Py_XDECREF (value);
	  Py_XDECREF (trace);
	  if (value_str == NULL)
	    {
	      gdbpy_print_stack ();
	      return NULL;
	    }

	  name_str = xstrprintf ("<error at %d>",
				 self->next_raw_index++);
	  item = Py_BuildValue ("(ss)", name_str, value_str);
	  xfree (name_str);
	  xfree (value_str);
	  if (item == NULL)
	    {
	      gdbpy_print_stack ();
	      return NULL;
	    }
	}
      else
	{
	  /* Any other kind of error.  */
	  gdbpy_print_stack ();
	  return NULL;
	}
    }

  if (!PyArg_ParseTuple (item, "sO", &name, &py_v))
    {
      gdbpy_print_stack ();
      error (_("Invalid item from the child list"));
    }

  vitem = XNEW (struct varobj_item);
  vitem->value = convert_value_from_python (py_v);
  if (vitem->value == NULL)
    gdbpy_print_stack ();
  vitem->name = xstrdup (name);

  self->next_raw_index++;
  do_cleanups (back_to);
  return vitem;
}

//.........这里部分代码省略.........
        goto bad;
    }

#if PY_VERSION_HEX >= 0x03030000
    if (cause) {
#else
    if (cause && cause != Py_None) {
#endif
        PyObject *fixed_cause;
        if (cause == Py_None) {
            // raise ... from None
            fixed_cause = NULL;
        } else if (PyExceptionClass_Check(cause)) {
            fixed_cause = PyObject_CallObject(cause, NULL);
            if (fixed_cause == NULL)
                goto bad;
        } else if (PyExceptionInstance_Check(cause)) {
            fixed_cause = cause;
            Py_INCREF(fixed_cause);
        } else {
            PyErr_SetString(PyExc_TypeError,
                            "exception causes must derive from "
                            "BaseException");
            goto bad;
        }
        PyException_SetCause(value, fixed_cause);
    }

    PyErr_SetObject(type, value);

    if (tb) {
#if CYTHON_COMPILING_IN_PYPY
        PyObject *tmp_type, *tmp_value, *tmp_tb;
        PyErr_Fetch(&tmp_type, &tmp_value, &tmp_tb);
        Py_INCREF(tb);
        PyErr_Restore(tmp_type, tmp_value, tb);
        Py_XDECREF(tmp_tb);
#else
        PyThreadState *tstate = PyThreadState_GET();
        PyObject* tmp_tb = tstate->curexc_traceback;
        if (tb != tmp_tb) {
            Py_INCREF(tb);
            tstate->curexc_traceback = tb;
            Py_XDECREF(tmp_tb);
        }
#endif
    }

bad:
    Py_XDECREF(owned_instance);
    return;
}
#endif

/////////////// GetException.proto ///////////////
//@substitute: naming
//@requires: PyThreadStateGet

#if CYTHON_FAST_THREAD_STATE
#define __Pyx_GetException(type, value, tb)  __Pyx__GetException($local_tstate_cname, type, value, tb)
static int __Pyx__GetException(PyThreadState *tstate, PyObject **type, PyObject **value, PyObject **tb); /*proto*/
#else
static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb); /*proto*/
#endif

/////////////// GetException ///////////////

static PyObject *
gen_send_ex(PyGenObject *gen, PyObject *arg, int exc, int closing)
{
    PyThreadState *tstate = PyThreadState_GET();
    PyFrameObject *f = gen->gi_frame;
    PyObject *result;

    if (gen->gi_running) {
        char *msg = "generator already executing";
        if (PyCoro_CheckExact(gen))
            msg = "coroutine already executing";
        PyErr_SetString(PyExc_ValueError, msg);
        return NULL;
    }
    if (f == NULL || f->f_stacktop == NULL) {
        if (PyCoro_CheckExact(gen) && !closing) {
            /* `gen` is an exhausted coroutine: raise an error,
               except when called from gen_close(), which should
               always be a silent method. */
            PyErr_SetString(
                PyExc_RuntimeError,
                "cannot reuse already awaited coroutine");
        } else if (arg && !exc) {
            /* `gen` is an exhausted generator:
               only set exception if called from send(). */
            PyErr_SetNone(PyExc_StopIteration);
        }
        return NULL;
    }

    if (f->f_lasti == -1) {
        if (arg && arg != Py_None) {
            char *msg = "can't send non-None value to a "
                        "just-started generator";
            if (PyCoro_CheckExact(gen))
                msg = "can't send non-None value to a "
                      "just-started coroutine";
            PyErr_SetString(PyExc_TypeError, msg);
            return NULL;
        }
    } else {
        /* Push arg onto the frame's value stack */
        result = arg ? arg : Py_None;
        Py_INCREF(result);
        *(f->f_stacktop++) = result;
    }

    /* Generators always return to their most recent caller, not
     * necessarily their creator. */
    Py_XINCREF(tstate->frame);
    assert(f->f_back == NULL);
    f->f_back = tstate->frame;

    gen->gi_running = 1;
    result = PyEval_EvalFrameEx(f, exc);
    gen->gi_running = 0;

    /* Don't keep the reference to f_back any longer than necessary.  It
     * may keep a chain of frames alive or it could create a reference
     * cycle. */
    assert(f->f_back == tstate->frame);
    Py_CLEAR(f->f_back);

    /* If the generator just returned (as opposed to yielding), signal
     * that the generator is exhausted. */
    if (result && f->f_stacktop == NULL) {
        if (result == Py_None) {
            /* Delay exception instantiation if we can */
            PyErr_SetNone(PyExc_StopIteration);
        } else {
            PyObject *e = PyObject_CallFunctionObjArgs(
                               PyExc_StopIteration, result, NULL);
            if (e != NULL) {
                PyErr_SetObject(PyExc_StopIteration, e);
                Py_DECREF(e);
            }
        }
        Py_CLEAR(result);
    }
    else if (!result && PyErr_ExceptionMatches(PyExc_StopIteration)) {
        /* Check for __future__ generator_stop and conditionally turn
         * a leaking StopIteration into RuntimeError (with its cause
         * set appropriately). */
        if (((PyCodeObject *)gen->gi_code)->co_flags &
              (CO_FUTURE_GENERATOR_STOP | CO_COROUTINE | CO_ITERABLE_COROUTINE))
        {
            PyObject *exc, *val, *val2, *tb;
            char *msg = "generator raised StopIteration";
            if (PyCoro_CheckExact(gen))
                msg = "coroutine raised StopIteration";
            PyErr_Fetch(&exc, &val, &tb);
            PyErr_NormalizeException(&exc, &val, &tb);
            if (tb != NULL)
                PyException_SetTraceback(val, tb);
            Py_DECREF(exc);
            Py_XDECREF(tb);
            PyErr_SetString(PyExc_RuntimeError, msg);
            PyErr_Fetch(&exc, &val2, &tb);
            PyErr_NormalizeException(&exc, &val2, &tb);
            Py_INCREF(val);
//.........这里部分代码省略.........

int
_PyIOBase_finalize(PyObject *self)
{
    PyObject *res;
    PyObject *tp, *v, *tb;
    int closed = 1;
    int is_zombie;

    /* If _PyIOBase_finalize() is called from a destructor, we need to
       resurrect the object as calling close() can invoke arbitrary code. */
    is_zombie = (Py_REFCNT(self) == 0);
    if (is_zombie) {
        ++Py_REFCNT(self);
    }
    PyErr_Fetch(&tp, &v, &tb);
    /* If `closed` doesn't exist or can't be evaluated as bool, then the
       object is probably in an unusable state, so ignore. */
    res = PyObject_GetAttr(self, _PyIO_str_closed);
    if (res == NULL)
        PyErr_Clear();
    else {
        closed = PyObject_IsTrue(res);
        Py_DECREF(res);
        if (closed == -1)
            PyErr_Clear();
    }
    if (closed == 0) {
        res = PyObject_CallMethodObjArgs((PyObject *) self, _PyIO_str_close,
                                          NULL);
        /* Silencing I/O errors is bad, but printing spurious tracebacks is
           equally as bad, and potentially more frequent (because of
           shutdown issues). */
        if (res == NULL)
            PyErr_Clear();
        else
            Py_DECREF(res);
    }
    PyErr_Restore(tp, v, tb);
    if (is_zombie) {
        if (--Py_REFCNT(self) != 0) {
            /* The object lives again. The following code is taken from
               slot_tp_del in typeobject.c. */
            Py_ssize_t refcnt = Py_REFCNT(self);
            _Py_NewReference(self);
            Py_REFCNT(self) = refcnt;
            /* If Py_REF_DEBUG, _Py_NewReference bumped _Py_RefTotal, so
             * we need to undo that. */
            _Py_DEC_REFTOTAL;
            /* If Py_TRACE_REFS, _Py_NewReference re-added self to the object
             * chain, so no more to do there.
             * If COUNT_ALLOCS, the original decref bumped tp_frees, and
             * _Py_NewReference bumped tp_allocs:  both of those need to be
             * undone.
             */
#ifdef COUNT_ALLOCS
            --Py_TYPE(self)->tp_frees;
            --Py_TYPE(self)->tp_allocs;
#endif
            return -1;
        }
    }
    return 0;
}