929 static PyObject *
930 alsamixer_list(PyObject *self, PyObject *args) 
931 {
932     snd_mixer_t *handle;
933     snd_mixer_selem_id_t *sid;
934     snd_mixer_elem_t *elem;
935     int err;
936     int cardidx = 0;
937     char cardname[32];
938     PyObject *result;
939     
940     if (!PyArg_ParseTuple(args,"|i:mixers",&cardidx)) 
when PyArg_ParseTuple() succeeds
taking False path
941         return NULL;
942     
943     sprintf(cardname, "hw:%d", cardidx);
944 
945     snd_mixer_selem_id_alloca(&sid);
946     err = alsamixer_gethandle(cardname, &handle);
947     if (err < 0) 
when considering range: 0 <= value <= 0x7fffffff
taking False path
948     {
949         PyErr_SetString(ALSAAudioError,snd_strerror(err));
950         snd_mixer_close(handle);
951         return NULL;
952     }
953 
954     result = PyList_New(0);
when PyList_New() succeeds
955 
956     for (elem = snd_mixer_first_elem(handle); elem; 
when treating unknown struct snd_mixer_elem_t * from alsaaudio.c:956 as non-NULL
taking True path
957          elem = snd_mixer_elem_next(elem)) 
958     {
959         PyObject *mixer;
960         snd_mixer_selem_get_id(elem, sid);
961         mixer = PyUnicode_FromString(snd_mixer_selem_id_get_name(sid));
when PyUnicodeUCS4_FromString() fails
962         PyList_Append(result,mixer);
returning -1 from PyList_Append() due to NULL item
963         Py_DECREF(mixer);
dereferencing NULL (mixer->ob_refcnt) at alsaaudio.c:963
964     }
965     snd_mixer_close(handle);
966 
967     return result;
968 }

929 static PyObject *
930 alsamixer_list(PyObject *self, PyObject *args) 
931 {
932     snd_mixer_t *handle;
933     snd_mixer_selem_id_t *sid;
934     snd_mixer_elem_t *elem;
935     int err;
936     int cardidx = 0;
937     char cardname[32];
938     PyObject *result;
939     
940     if (!PyArg_ParseTuple(args,"|i:mixers",&cardidx)) 
when PyArg_ParseTuple() succeeds
taking False path
941         return NULL;
942     
943     sprintf(cardname, "hw:%d", cardidx);
944 
945     snd_mixer_selem_id_alloca(&sid);
946     err = alsamixer_gethandle(cardname, &handle);
947     if (err < 0) 
when considering range: 0 <= value <= 0x7fffffff
taking False path
948     {
949         PyErr_SetString(ALSAAudioError,snd_strerror(err));
950         snd_mixer_close(handle);
951         return NULL;
952     }
953 
954     result = PyList_New(0);
when PyList_New() fails
955 
956     for (elem = snd_mixer_first_elem(handle); elem; 
when treating unknown struct snd_mixer_elem_t * from alsaaudio.c:956 as non-NULL
taking True path
957          elem = snd_mixer_elem_next(elem)) 
958     {
959         PyObject *mixer;
960         snd_mixer_selem_get_id(elem, sid);
961         mixer = PyUnicode_FromString(snd_mixer_selem_id_get_name(sid));
when PyUnicodeUCS4_FromString() succeeds
962         PyList_Append(result,mixer);
calling PyList_Append with NULL as argument 1 (result) at alsaaudio.c:962
PyList_Append() invokes Py_TYPE() on the pointer via the PyList_Check() macro, thus accessing (NULL)->ob_type
found 1 similar trace(s) to this
963         Py_DECREF(mixer);
964     }
965     snd_mixer_close(handle);
966 
967     return result;
968 }