CHECK_VALIDITY(c->pstream, c->authorized, tag, PA_ERR_ACCESS);
CHECK_VALIDITY(c->pstream, !name || pa_namereg_is_valid_name(name), tag, PA_ERR_INVALID);
CHECK_VALIDITY(c->pstream, (idx != PA_INVALID_INDEX) ^ (name != NULL), tag, PA_ERR_INVALID);
CHECK_VALIDITY(c->pstream, c->authorized, tag, PA_ERR_ACCESS);
CHECK_VALIDITY(c->pstream, !name || pa_namereg_is_valid_name(name), tag, PA_ERR_INVALID);
CHECK_VALIDITY(c->pstream, (idx != PA_INVALID_INDEX) ^ (name != NULL), tag, PA_ERR_INVALID);