From 9616a82e7802241a4b74cf7ae38d43c37bf66e48 Mon Sep 17 00:00:00 2001 From: bladebryan Date: Fri, 21 Apr 2017 23:10:46 -0700 Subject: [PATCH] bpo-29960 _random.Random corrupted on exception in setstate(). (#1019) --- Lib/test/test_random.py | 5 +++++ Misc/ACKS | 1 + Misc/NEWS | 3 +++ Modules/_randommodule.c | 5 ++++- 4 files changed, 13 insertions(+), 1 deletion(-) diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py index 78909dd96e..48077fb5db 100644 --- a/Lib/test/test_random.py +++ b/Lib/test/test_random.py @@ -423,6 +423,7 @@ class MersenneTwister_TestBasicOps(TestBasicOps, unittest.TestCase): self.assertRaises(ValueError, self.gen.setstate, (1, None, None)) def test_setstate_middle_arg(self): + start_state = self.gen.getstate() # Wrong type, s/b tuple self.assertRaises(TypeError, self.gen.setstate, (2, None, None)) # Wrong length, s/b 625 @@ -436,6 +437,10 @@ class MersenneTwister_TestBasicOps(TestBasicOps, unittest.TestCase): self.gen.setstate((2, (1,)*624+(625,), None)) with self.assertRaises((ValueError, OverflowError)): self.gen.setstate((2, (1,)*624+(-1,), None)) + # Failed calls to setstate() should not have changed the state. + bits100 = self.gen.getrandbits(100) + self.gen.setstate(start_state) + self.assertEqual(self.gen.getrandbits(100), bits100) # Little trick to make "tuple(x % (2**32) for x in internalstate)" # raise ValueError. I cannot think of a simple way to achieve this, so diff --git a/Misc/ACKS b/Misc/ACKS index d4f20c548f..ab41431add 100644 --- a/Misc/ACKS +++ b/Misc/ACKS @@ -1110,6 +1110,7 @@ Milan Oberkirch Pascal Oberndoerfer Jeffrey Ollie Adam Olsen +Bryan Olson Grant Olson Koray Oner Piet van Oostrum diff --git a/Misc/NEWS b/Misc/NEWS index fe1b0f839d..72fcded6a1 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -317,6 +317,9 @@ Extension Modules Library ------- +- bpo-29960: Preserve generator state when _random.Random.setstate() + raises an exception. Patch by Bryan Olson. + - bpo-29802: Fixed reference counting in module-level struct functions when pass arguments of wrong type. diff --git a/Modules/_randommodule.c b/Modules/_randommodule.c index 6db1d2dfe6..9953654bdc 100644 --- a/Modules/_randommodule.c +++ b/Modules/_randommodule.c @@ -348,6 +348,7 @@ random_setstate(RandomObject *self, PyObject *state) int i; unsigned long element; long index; + uint32_t new_state[N]; if (!PyTuple_Check(state)) { PyErr_SetString(PyExc_TypeError, @@ -364,7 +365,7 @@ random_setstate(RandomObject *self, PyObject *state) element = PyLong_AsUnsignedLong(PyTuple_GET_ITEM(state, i)); if (element == (unsigned long)-1 && PyErr_Occurred()) return NULL; - self->state[i] = (uint32_t)element; + new_state[i] = (uint32_t)element; } index = PyLong_AsLong(PyTuple_GET_ITEM(state, i)); @@ -375,6 +376,8 @@ random_setstate(RandomObject *self, PyObject *state) return NULL; } self->index = (int)index; + for (i = 0; i < N; i++) + self->state[i] = new_state[i]; Py_RETURN_NONE; } -- 2.40.0