Issue #22117: Fix rounding in _PyTime_FromSecondsObject()

* Rename _PyTime_FromObject() to _PyTime_FromSecondsObject()
* Add _PyTime_AsNanosecondsObject() and _testcapi.pytime_fromsecondsobject()
* Add unit tests

Include/pytime.h

@@ -121,15 +121,18 @@ typedef PY_INT64_T _PyTime_t;
 
 /* Convert a Python float or int to a timetamp.
    Raise an exception and return -1 on error, return 0 on success. */
-PyAPI_FUNC(int) _PyTime_FromObject(_PyTime_t *t,
+PyAPI_FUNC(int) _PyTime_FromSecondsObject(_PyTime_t *t,
     PyObject *obj,
     _PyTime_round_t round);
 
 /* Convert timestamp to a number of milliseconds (10^-3 seconds). */
-PyAPI_FUNC(_PyTime_t)
-_PyTime_AsMilliseconds(_PyTime_t t,
+PyAPI_FUNC(_PyTime_t) _PyTime_AsMilliseconds(_PyTime_t t,
     _PyTime_round_t round);
 
+/* Convert timestamp to a number of nanoseconds (10^-9 seconds) as a Python int
+   object. */
+PyAPI_FUNC(PyObject *) _PyTime_AsNanosecondsObject(_PyTime_t t);
+
 /* Convert a timestamp to a timeval structure. */
 PyAPI_FUNC(int) _PyTime_AsTimeval(_PyTime_t t,
     struct timeval *tv,

Modules/_testcapimodule.c

@@ -3378,6 +3378,22 @@ return_result_with_error(PyObject *self, PyObject *args)
     Py_RETURN_NONE;
 }
 
+static PyObject *
+test_pytime_fromsecondsobject(PyObject *self, PyObject *args)
+{
+    PyObject *obj;
+    int round;
+    _PyTime_t ts;
+
+    if (!PyArg_ParseTuple(args, "Oi", &obj, &round))
+        return NULL;
+    if (check_time_rounding(round) < 0)
+        return NULL;
+    if (_PyTime_FromSecondsObject(&ts, obj, round) == -1)
+        return NULL;
+    return _PyTime_AsNanosecondsObject(ts);
+}
+
 
 static PyMethodDef TestMethods[] = {
     {"raise_exception",         raise_exception,                 METH_VARARGS},
@@ -3541,6 +3557,7 @@ static PyMethodDef TestMethods[] = {
         return_null_without_error, METH_NOARGS},
     {"return_result_with_error",
         return_result_with_error, METH_NOARGS},
+    {"pytime_fromsecondsobject", test_pytime_fromsecondsobject,  METH_VARARGS},
     {NULL, NULL} /* sentinel */
 };
 

Modules/timemodule.c

@@ -221,7 +221,7 @@ static PyObject *
 time_sleep(PyObject *self, PyObject *obj)
 {
     _PyTime_t secs;
-    if (_PyTime_FromObject(&secs, obj, _PyTime_ROUND_UP))
+    if (_PyTime_FromSecondsObject(&secs, obj, _PyTime_ROUND_UP))
         return NULL;
     if (secs < 0) {
         PyErr_SetString(PyExc_ValueError,

Python/pytime.c

@@ -424,7 +424,7 @@ _PyTime_FromTimespec(_PyTime_t *tp, struct timespec *ts)
 #endif
 
 int
-_PyTime_FromObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
+_PyTime_FromSecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
 {
     if (PyFloat_Check(obj)) {
         double d, err;
@@ -433,8 +433,7 @@ _PyTime_FromObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
         d = PyFloat_AsDouble(obj);
         d *= 1e9;
 
-        /* FIXME: use sign */
-        if (round == _PyTime_ROUND_UP)
+        if ((round == _PyTime_ROUND_UP) ^ (d < 0))
             d = ceil(d);
         else
             d = floor(d);
@@ -471,6 +470,18 @@ _PyTime_FromObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
     }
 }
 
+PyObject *
+_PyTime_AsNanosecondsObject(_PyTime_t t)
+{
+#ifdef HAVE_LONG_LONG
+    assert(sizeof(PY_LONG_LONG) >= sizeof(_PyTime_t));
+    return PyLong_FromLongLong((PY_LONG_LONG)t);
+#else
+    assert(sizeof(long) >= sizeof(_PyTime_t));
+    return PyLong_FromLong((long)t);
+#endif
+}
+
 static _PyTime_t
 _PyTime_Multiply(_PyTime_t t, unsigned int multiply, _PyTime_round_t round)
 {