From 93f562c4f9a751034616068468e7dc2cfd022275 Mon Sep 17 00:00:00 2001 From: Mark Dickinson Date: Sat, 30 Jan 2010 10:30:15 +0000 Subject: Merged revisions 77842 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r77842 | mark.dickinson | 2010-01-30 10:08:33 +0000 (Sat, 30 Jan 2010) | 4 lines Issue #7767: Add new C-API function PyLong_AsLongLongAndOverflow, a long long variant of PyLong_AsLongAndOverflow. Patch by Case Van Horsen. ........ --- Doc/c-api/long.rst | 13 ++++ Include/longobject.h | 1 + Misc/NEWS | 3 + Modules/_testcapimodule.c | 167 ++++++++++++++++++++++++++++++++++++++++++++++ Objects/longobject.c | 96 ++++++++++++++++++++++++++ 5 files changed, 280 insertions(+) diff --git a/Doc/c-api/long.rst b/Doc/c-api/long.rst index 083fe8b..ba9949f 100644 --- a/Doc/c-api/long.rst +++ b/Doc/c-api/long.rst @@ -130,6 +130,19 @@ All integers are implemented as "long" integer objects of arbitrary size. be ``0``. +.. cfunction:: PY_LONG_LONG PyLong_AsLongLongAndOverflow(PyObject *pylong, int* overflow) + + Return a C :ctype:`long long` representation of the contents of + *pylong*. If *pylong* is greater than :const:`PY_LLONG_MAX` or less + than :const:`PY_LLONG_MIN`, set `*overflow` to ``1`` or ``-1``, + respectively, and return ``-1``; otherwise, set `*overflow` to + ``0``. If any other exception occurs (for example a TypeError or + MemoryError), then ``-1`` will be returned and ``*overflow`` will + be ``0``. + + .. versionadded:: 3.2 + + .. cfunction:: Py_ssize_t PyLong_AsSsize_t(PyObject *pylong) .. index:: diff --git a/Include/longobject.h b/Include/longobject.h index 2bb1e71..83d780d 100644 --- a/Include/longobject.h +++ b/Include/longobject.h @@ -62,6 +62,7 @@ PyAPI_FUNC(PyObject *) PyLong_FromUnsignedLongLong(unsigned PY_LONG_LONG); PyAPI_FUNC(PY_LONG_LONG) PyLong_AsLongLong(PyObject *); PyAPI_FUNC(unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLong(PyObject *); PyAPI_FUNC(unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLongMask(PyObject *); +PyAPI_FUNC(PY_LONG_LONG) PyLong_AsLongLongAndOverflow(PyObject *, int *); #endif /* HAVE_LONG_LONG */ PyAPI_FUNC(PyObject *) PyLong_FromString(char *, char **, int); diff --git a/Misc/NEWS b/Misc/NEWS index 0d94c45..d21121d 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -192,6 +192,9 @@ Core and Builtins C-API ----- +- Issue #7767: New function PyLong_AsLongLongAndOverflow added, + analogous to PyLong_AsLongAndOverflow. + - Make PyUnicode_CompareWithASCIIString return not equal if the Python string has '\0' at the end. diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c index 5671783..b635483 100644 --- a/Modules/_testcapimodule.c +++ b/Modules/_testcapimodule.c @@ -524,6 +524,171 @@ test_long_and_overflow(PyObject *self) return Py_None; } +/* Test the PyLong_AsLongLongAndOverflow API. General conversion to + PY_LONG_LONG is tested by test_long_api_inner. This test will + concentrate on proper handling of overflow. +*/ + +static PyObject * +test_long_long_and_overflow(PyObject *self) +{ + PyObject *num, *one, *temp; + PY_LONG_LONG value; + int overflow; + + /* Test that overflow is set properly for a large value. */ + /* num is a number larger than PY_LLONG_MAX on a typical machine. */ + num = PyLong_FromString("FFFFFFFFFFFFFFFFFFFFFFFF", NULL, 16); + if (num == NULL) + return NULL; + overflow = 1234; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != -1) + return raiseTestError("test_long_long_and_overflow", + "return value was not set to -1"); + if (overflow != 1) + return raiseTestError("test_long_long_and_overflow", + "overflow was not set to 1"); + + /* Same again, with num = PY_LLONG_MAX + 1 */ + num = PyLong_FromLongLong(PY_LLONG_MAX); + if (num == NULL) + return NULL; + one = PyLong_FromLong(1L); + if (one == NULL) { + Py_DECREF(num); + return NULL; + } + temp = PyNumber_Add(num, one); + Py_DECREF(one); + Py_DECREF(num); + num = temp; + if (num == NULL) + return NULL; + overflow = 0; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != -1) + return raiseTestError("test_long_long_and_overflow", + "return value was not set to -1"); + if (overflow != 1) + return raiseTestError("test_long_long_and_overflow", + "overflow was not set to 1"); + + /* Test that overflow is set properly for a large negative value. */ + /* num is a number smaller than PY_LLONG_MIN on a typical platform */ + num = PyLong_FromString("-FFFFFFFFFFFFFFFFFFFFFFFF", NULL, 16); + if (num == NULL) + return NULL; + overflow = 1234; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != -1) + return raiseTestError("test_long_long_and_overflow", + "return value was not set to -1"); + if (overflow != -1) + return raiseTestError("test_long_long_and_overflow", + "overflow was not set to -1"); + + /* Same again, with num = PY_LLONG_MIN - 1 */ + num = PyLong_FromLongLong(PY_LLONG_MIN); + if (num == NULL) + return NULL; + one = PyLong_FromLong(1L); + if (one == NULL) { + Py_DECREF(num); + return NULL; + } + temp = PyNumber_Subtract(num, one); + Py_DECREF(one); + Py_DECREF(num); + num = temp; + if (num == NULL) + return NULL; + overflow = 0; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != -1) + return raiseTestError("test_long_long_and_overflow", + "return value was not set to -1"); + if (overflow != -1) + return raiseTestError("test_long_long_and_overflow", + "overflow was not set to -1"); + + /* Test that overflow is cleared properly for small values. */ + num = PyLong_FromString("FF", NULL, 16); + if (num == NULL) + return NULL; + overflow = 1234; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != 0xFF) + return raiseTestError("test_long_long_and_overflow", + "expected return value 0xFF"); + if (overflow != 0) + return raiseTestError("test_long_long_and_overflow", + "overflow was not cleared"); + + num = PyLong_FromString("-FF", NULL, 16); + if (num == NULL) + return NULL; + overflow = 0; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != -0xFF) + return raiseTestError("test_long_long_and_overflow", + "expected return value 0xFF"); + if (overflow != 0) + return raiseTestError("test_long_long_and_overflow", + "overflow was set incorrectly"); + + num = PyLong_FromLongLong(PY_LLONG_MAX); + if (num == NULL) + return NULL; + overflow = 1234; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != PY_LLONG_MAX) + return raiseTestError("test_long_long_and_overflow", + "expected return value PY_LLONG_MAX"); + if (overflow != 0) + return raiseTestError("test_long_long_and_overflow", + "overflow was not cleared"); + + num = PyLong_FromLongLong(PY_LLONG_MIN); + if (num == NULL) + return NULL; + overflow = 0; + value = PyLong_AsLongLongAndOverflow(num, &overflow); + Py_DECREF(num); + if (value == -1 && PyErr_Occurred()) + return NULL; + if (value != PY_LLONG_MIN) + return raiseTestError("test_long_long_and_overflow", + "expected return value PY_LLONG_MIN"); + if (overflow != 0) + return raiseTestError("test_long_long_and_overflow", + "overflow was not cleared"); + + Py_INCREF(Py_None); + return Py_None; +} + /* Test the L code for PyArg_ParseTuple. This should deliver a PY_LONG_LONG for both long and int arguments. The test may leak a little memory if it fails. @@ -1791,6 +1956,8 @@ static PyMethodDef TestMethods[] = { {"getargs_L", getargs_L, METH_VARARGS}, {"getargs_K", getargs_K, METH_VARARGS}, {"test_longlong_api", test_longlong_api, METH_NOARGS}, + {"test_long_long_and_overflow", + (PyCFunction)test_long_long_and_overflow, METH_NOARGS}, {"test_L_code", (PyCFunction)test_L_code, METH_NOARGS}, {"codec_incrementalencoder", (PyCFunction)codec_incrementalencoder, METH_VARARGS}, diff --git a/Objects/longobject.c b/Objects/longobject.c index afac856..db7a91c 100644 --- a/Objects/longobject.c +++ b/Objects/longobject.c @@ -971,6 +971,7 @@ PyLong_AsVoidPtr(PyObject *vv) */ #define IS_LITTLE_ENDIAN (int)*(unsigned char*)&one +#define PY_ABS_LLONG_MIN (0-(unsigned PY_LONG_LONG)PY_LLONG_MIN) /* Create a new long int object from a C PY_LONG_LONG int. */ @@ -1269,6 +1270,101 @@ PyLong_AsUnsignedLongLongMask(register PyObject *op) } #undef IS_LITTLE_ENDIAN +/* Get a C long long int from a Python long or Python int object. + On overflow, returns -1 and sets *overflow to 1 or -1 depending + on the sign of the result. Otherwise *overflow is 0. + + For other errors (e.g., type error), returns -1 and sets an error + condition. +*/ + +PY_LONG_LONG +PyLong_AsLongLongAndOverflow(PyObject *vv, int *overflow) +{ + /* This version by Tim Peters */ + register PyLongObject *v; + unsigned PY_LONG_LONG x, prev; + PY_LONG_LONG res; + Py_ssize_t i; + int sign; + int do_decref = 0; /* if nb_int was called */ + + *overflow = 0; + if (vv == NULL) { + PyErr_BadInternalCall(); + return -1; + } + + if (!PyLong_Check(vv)) { + PyNumberMethods *nb; + nb = vv->ob_type->tp_as_number; + if (nb == NULL || nb->nb_int == NULL) { + PyErr_SetString(PyExc_TypeError, + "an integer is required"); + return -1; + } + vv = (*nb->nb_int) (vv); + if (vv == NULL) + return -1; + do_decref = 1; + if (!PyLong_Check(vv)) { + Py_DECREF(vv); + PyErr_SetString(PyExc_TypeError, + "nb_int should return int object"); + return -1; + } + } + + res = -1; + v = (PyLongObject *)vv; + i = Py_SIZE(v); + + switch (i) { + case -1: + res = -(sdigit)v->ob_digit[0]; + break; + case 0: + res = 0; + break; + case 1: + res = v->ob_digit[0]; + break; + default: + sign = 1; + x = 0; + if (i < 0) { + sign = -1; + i = -(i); + } + while (--i >= 0) { + prev = x; + x = (x << PyLong_SHIFT) + v->ob_digit[i]; + if ((x >> PyLong_SHIFT) != prev) { + *overflow = sign; + goto exit; + } + } + /* Haven't lost any bits, but casting to long requires extra + * care (see comment above). + */ + if (x <= (unsigned PY_LONG_LONG)PY_LLONG_MAX) { + res = (PY_LONG_LONG)x * sign; + } + else if (sign < 0 && x == PY_ABS_LLONG_MIN) { + res = PY_LLONG_MIN; + } + else { + *overflow = sign; + /* res is already set to -1 */ + } + } + exit: + if (do_decref) { + Py_DECREF(vv); + } + return res; +} + #endif /* HAVE_LONG_LONG */ #define CHECK_BINOP(v,w) \ -- cgit v0.12