diff options
| author | Xiang Zhang <angwerzx@126.com> | 2017-05-10 10:19:41 (GMT) |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2017-05-10 10:19:41 (GMT) |
| commit | 2ddf5a19c3a06978edff2c8ba0aaf5df3528204a (patch) | |
| tree | 8a4b6f0ae35ee772702912050fd252b9e360c482 | |
| parent | 305ccbe27ea5ba82fd2d8c32ec739f980e524330 (diff) | |
| download | cpython-2ddf5a19c3a06978edff2c8ba0aaf5df3528204a.zip cpython-2ddf5a19c3a06978edff2c8ba0aaf5df3528204a.tar.gz cpython-2ddf5a19c3a06978edff2c8ba0aaf5df3528204a.tar.bz2 | |
bpo-30281: Fix the default value for stop in PySlice_Unpack() (#1480)
| -rw-r--r-- | Doc/c-api/slice.rst | 2 | ||||
| -rw-r--r-- | Objects/sliceobject.c | 8 | ||||
| -rw-r--r-- | Python/ceval.c | 2 |
3 files changed, 7 insertions, 5 deletions
diff --git a/Doc/c-api/slice.rst b/Doc/c-api/slice.rst index aece011..f8395ec 100644 --- a/Doc/c-api/slice.rst +++ b/Doc/c-api/slice.rst @@ -75,7 +75,7 @@ Slice Objects Extract the start, stop and step data members from a slice object as C integers. Silently reduce values larger than ``PY_SSIZE_T_MAX`` to ``PY_SSIZE_T_MAX``, silently boost the start and stop values less than - ``-PY_SSIZE_T_MAX-1`` to ``-PY_SSIZE_T_MAX-1``, and silently boost the step + ``PY_SSIZE_T_MIN`` to ``PY_SSIZE_T_MIN``, and silently boost the step values less than ``-PY_SSIZE_T_MAX`` to ``-PY_SSIZE_T_MAX``. Return ``-1`` on error, ``0`` on success. diff --git a/Objects/sliceobject.c b/Objects/sliceobject.c index ebc4464..4263737 100644 --- a/Objects/sliceobject.c +++ b/Objects/sliceobject.c @@ -197,6 +197,8 @@ PySlice_Unpack(PyObject *_r, PySliceObject *r = (PySliceObject*)_r; /* this is harder to get right than you might think */ + Py_BUILD_ASSERT(PY_SSIZE_T_MIN + 1 <= -PY_SSIZE_T_MAX); + if (r->step == Py_None) { *step = 1; } @@ -217,14 +219,14 @@ PySlice_Unpack(PyObject *_r, } if (r->start == Py_None) { - *start = *step < 0 ? PY_SSIZE_T_MAX-1 : 0;; + *start = *step < 0 ? PY_SSIZE_T_MAX : 0; } else { if (!_PyEval_SliceIndex(r->start, start)) return -1; } if (r->stop == Py_None) { - *stop = *step < 0 ? -PY_SSIZE_T_MAX : PY_SSIZE_T_MAX; + *stop = *step < 0 ? PY_SSIZE_T_MIN : PY_SSIZE_T_MAX; } else { if (!_PyEval_SliceIndex(r->stop, stop)) return -1; @@ -258,7 +260,7 @@ PySlice_AdjustIndices(Py_ssize_t length, *stop = (step < 0) ? -1 : 0; } } - else if (*stop >= length) { + else if (*stop >= length) { *stop = (step < 0) ? length - 1 : length; } diff --git a/Python/ceval.c b/Python/ceval.c index afd305c..23fd088 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -4889,7 +4889,7 @@ do_call_core(PyObject *func, PyObject *callargs, PyObject *kwdict) /* Extract a slice index from a PyLong or an object with the nb_index slot defined, and store in *pi. Silently reduce values larger than PY_SSIZE_T_MAX to PY_SSIZE_T_MAX, - and silently boost values less than -PY_SSIZE_T_MAX-1 to -PY_SSIZE_T_MAX-1. + and silently boost values less than PY_SSIZE_T_MIN to PY_SSIZE_T_MIN. Return 0 on error, 1 on success. */ int |