diff options
| -rw-r--r-- | Objects/rangeobject.c | 90 |
1 files changed, 80 insertions, 10 deletions
diff --git a/Objects/rangeobject.c b/Objects/rangeobject.c index d4622eb..cec38f0 100644 --- a/Objects/rangeobject.c +++ b/Objects/rangeobject.c @@ -11,21 +11,80 @@ typedef struct { long step; long len; int reps; + long totlen; } rangeobject; +static int +long_mul(long i, long j, long *kk) +{ + PyObject *a; + PyObject *b; + PyObject *c; + + if ((a = PyInt_FromLong(i)) == NULL) + return 0; + + if ((b = PyInt_FromLong(j)) == NULL) + return 0; + + c = PyNumber_Multiply(a, b); + + Py_DECREF(a); + Py_DECREF(b); + + if (c == NULL) + return 0; + + *kk = PyInt_AS_LONG(c); + Py_DECREF(c); + + if (*kk > INT_MAX) { + PyErr_SetString(PyExc_OverflowError, + "integer multiplication"); + return 0; + } + else + return 1; +} PyObject * PyRange_New(long start, long len, long step, int reps) { + long totlen = -1; rangeobject *obj = PyObject_NEW(rangeobject, &PyRange_Type); if (obj == NULL) return NULL; + if (len == 0 || reps <= 0) { + start = 0; + len = 0; + step = 1; + reps = 1; + totlen = 0; + } + else { + long last = start + (len - 1) * step; + if ((step > 0) ? + (last > (PyInt_GetMax() - step)) + :(last < (-1 - PyInt_GetMax() - step))) { + PyErr_SetString(PyExc_OverflowError, + "integer addition"); + return NULL; + } + if (! long_mul(len, (long) reps, &totlen)) { + if(!PyErr_ExceptionMatches(PyExc_OverflowError)) + return NULL; + PyErr_Clear(); + totlen = -1; + } + } + obj->start = start; obj->len = len; obj->step = step; obj->reps = reps; + obj->totlen = totlen; return (PyObject *) obj; } @@ -39,11 +98,12 @@ range_dealloc(rangeobject *r) static PyObject * range_item(rangeobject *r, int i) { - if (i < 0 || i >= r->len * r->reps) { - PyErr_SetString(PyExc_IndexError, + if (i < 0 || i >= r->totlen) + if (r->totlen!=-1) { + PyErr_SetString(PyExc_IndexError, "xrange object index out of range"); - return NULL; - } + return NULL; + } return PyInt_FromLong(r->start + (i % r->len) * r->step); } @@ -51,7 +111,10 @@ range_item(rangeobject *r, int i) static int range_length(rangeobject *r) { - return r->len * r->reps; + if (r->totlen == -1) + PyErr_SetString(PyExc_OverflowError, + "xrange object has too many items"); + return r->totlen; } static PyObject * @@ -93,7 +156,9 @@ range_concat(rangeobject *r, PyObject *obj) static PyObject * range_repeat(rangeobject *r, int n) { - if (n < 0) + long lreps = 0; + + if (n <= 0) return (PyObject *) PyRange_New(0, 0, 1, 1); else if (n == 1) { @@ -101,12 +166,15 @@ range_repeat(rangeobject *r, int n) return (PyObject *) r; } + else if (! long_mul((long) r->reps, (long) n, &lreps)) + return NULL; + else return (PyObject *) PyRange_New( r->start, r->len, r->step, - r->reps * n); + (int) lreps); } static int @@ -161,15 +229,17 @@ range_tolist(rangeobject *self, PyObject *args) { PyObject *thelist; int j; - int len = self->len * self->reps; if (! PyArg_ParseTuple(args, ":tolist")) return NULL; - if ((thelist = PyList_New(len)) == NULL) + if (self->totlen == -1) + return PyErr_NoMemory(); + + if ((thelist = PyList_New(self->totlen)) == NULL) return NULL; - for (j = 0; j < len; ++j) + for (j = 0; j < self->totlen; ++j) if ((PyList_SetItem(thelist, j, (PyObject *) PyInt_FromLong( self->start + (j % self->len) * self->step))) < 0) return NULL; |