diff options
Diffstat (limited to 'Objects/rangeobject.c')
| -rw-r--r-- | Objects/rangeobject.c | 205 |
1 files changed, 6 insertions, 199 deletions
diff --git a/Objects/rangeobject.c b/Objects/rangeobject.c index d790ca8f47..a4d9fb3244 100644 --- a/Objects/rangeobject.c +++ b/Objects/rangeobject.c @@ -318,195 +318,6 @@ range_item(rangeobject *r, Py_ssize_t i) return res; } -/* Additional helpers, since the standard slice helpers - * all clip to PY_SSIZE_T_MAX - */ - -/* Replace _PyEval_SliceIndex */ -static PyObject * -compute_slice_element(PyObject *obj) -{ - PyObject *result = NULL; - if (obj != NULL) { - if (PyIndex_Check(obj)) { - result = PyNumber_Index(obj); - } - else { - PyErr_SetString(PyExc_TypeError, - "slice indices must be integers or " - "None or have an __index__ method"); - } - } - return result; -} - -/* Replace PySlice_GetIndicesEx - * Result indicates whether or not the slice is empty - * (-1 = error, 0 = empty slice, 1 = slice contains elements) - */ -static int -compute_slice_indices(rangeobject *r, PySliceObject *slice, - PyObject **start, PyObject **stop, PyObject **step) -{ - int cmp_result, has_elements; - Py_ssize_t clamped_step = 0; - PyObject *zero = NULL, *one = NULL, *neg_one = NULL, *candidate = NULL; - PyObject *tmp_start = NULL, *tmp_stop = NULL, *tmp_step = NULL; - zero = PyLong_FromLong(0); - if (zero == NULL) goto Fail; - one = PyLong_FromLong(1); - if (one == NULL) goto Fail; - neg_one = PyLong_FromLong(-1); - if (neg_one == NULL) goto Fail; - - /* Calculate step value */ - if (slice->step == Py_None) { - clamped_step = 1; - tmp_step = one; - Py_INCREF(tmp_step); - } else { - if (!_PyEval_SliceIndex(slice->step, &clamped_step)) goto Fail; - if (clamped_step == 0) { - PyErr_SetString(PyExc_ValueError, - "slice step cannot be zero"); - goto Fail; - } - tmp_step = compute_slice_element(slice->step); - if (tmp_step == NULL) goto Fail; - } - - /* Calculate start value */ - if (slice->start == Py_None) { - if (clamped_step < 0) { - tmp_start = PyNumber_Subtract(r->length, one); - if (tmp_start == NULL) goto Fail; - } else { - tmp_start = zero; - Py_INCREF(tmp_start); - } - } else { - candidate = compute_slice_element(slice->start); - if (candidate == NULL) goto Fail; - cmp_result = PyObject_RichCompareBool(candidate, zero, Py_LT); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* candidate < 0 */ - tmp_start = PyNumber_Add(r->length, candidate); - if (tmp_start == NULL) goto Fail; - Py_CLEAR(candidate); - } else { - /* candidate >= 0 */ - tmp_start = candidate; - candidate = NULL; - } - cmp_result = PyObject_RichCompareBool(tmp_start, zero, Py_LT); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* tmp_start < 0 */ - Py_CLEAR(tmp_start); - if (clamped_step < 0) { - tmp_start = neg_one; - } else { - tmp_start = zero; - } - Py_INCREF(tmp_start); - } else { - /* tmp_start >= 0 */ - cmp_result = PyObject_RichCompareBool(tmp_start, r->length, Py_GE); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* tmp_start >= r->length */ - Py_CLEAR(tmp_start); - if (clamped_step < 0) { - tmp_start = PyNumber_Subtract(r->length, one); - if (tmp_start == NULL) goto Fail; - } else { - tmp_start = r->length; - Py_INCREF(tmp_start); - } - } - } - } - - /* Calculate stop value */ - if (slice->stop == Py_None) { - if (clamped_step < 0) { - tmp_stop = neg_one; - } else { - tmp_stop = r->length; - } - Py_INCREF(tmp_stop); - } else { - candidate = compute_slice_element(slice->stop); - if (candidate == NULL) goto Fail; - cmp_result = PyObject_RichCompareBool(candidate, zero, Py_LT); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* candidate < 0 */ - tmp_stop = PyNumber_Add(r->length, candidate); - if (tmp_stop == NULL) goto Fail; - Py_CLEAR(candidate); - } else { - /* candidate >= 0 */ - tmp_stop = candidate; - candidate = NULL; - } - cmp_result = PyObject_RichCompareBool(tmp_stop, zero, Py_LT); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* tmp_stop < 0 */ - Py_CLEAR(tmp_stop); - if (clamped_step < 0) { - tmp_stop = neg_one; - } else { - tmp_stop = zero; - } - Py_INCREF(tmp_stop); - } else { - /* tmp_stop >= 0 */ - cmp_result = PyObject_RichCompareBool(tmp_stop, r->length, Py_GE); - if (cmp_result == -1) goto Fail; - if (cmp_result) { - /* tmp_stop >= r->length */ - Py_CLEAR(tmp_stop); - if (clamped_step < 0) { - tmp_stop = PyNumber_Subtract(r->length, one); - if (tmp_stop == NULL) goto Fail; - } else { - tmp_stop = r->length; - Py_INCREF(tmp_stop); - } - } - } - } - - /* Check if the slice is empty or not */ - if (clamped_step < 0) { - has_elements = PyObject_RichCompareBool(tmp_start, tmp_stop, Py_GT); - } else { - has_elements = PyObject_RichCompareBool(tmp_start, tmp_stop, Py_LT); - } - if (has_elements == -1) goto Fail; - - *start = tmp_start; - *stop = tmp_stop; - *step = tmp_step; - Py_DECREF(neg_one); - Py_DECREF(one); - Py_DECREF(zero); - return has_elements; - - Fail: - Py_XDECREF(tmp_start); - Py_XDECREF(tmp_stop); - Py_XDECREF(tmp_step); - Py_XDECREF(candidate); - Py_XDECREF(neg_one); - Py_XDECREF(one); - Py_XDECREF(zero); - return -1; -} - static PyObject * compute_slice(rangeobject *r, PyObject *_slice) { @@ -514,10 +325,11 @@ compute_slice(rangeobject *r, PyObject *_slice) rangeobject *result; PyObject *start = NULL, *stop = NULL, *step = NULL; PyObject *substart = NULL, *substop = NULL, *substep = NULL; - int has_elements; + int error; - has_elements = compute_slice_indices(r, slice, &start, &stop, &step); - if (has_elements == -1) return NULL; + error = _PySlice_GetLongIndices(slice, r->length, &start, &stop, &step); + if (error == -1) + return NULL; substep = PyNumber_Multiply(r->step, step); if (substep == NULL) goto fail; @@ -527,13 +339,8 @@ compute_slice(rangeobject *r, PyObject *_slice) if (substart == NULL) goto fail; Py_CLEAR(start); - if (has_elements) { - substop = compute_item(r, stop); - if (substop == NULL) goto fail; - } else { - substop = substart; - Py_INCREF(substop); - } + substop = compute_item(r, stop); + if (substop == NULL) goto fail; Py_CLEAR(stop); result = make_range_object(Py_TYPE(r), substart, substop, substep); |