diff options
| -rw-r--r-- | Misc/NEWS.d/next/Library/2022-03-08-11-34-06.bpo-23325.3VQnfo.rst | 2 | ||||
| -rw-r--r-- | Modules/signalmodule.c | 36 |
2 files changed, 25 insertions, 13 deletions
diff --git a/Misc/NEWS.d/next/Library/2022-03-08-11-34-06.bpo-23325.3VQnfo.rst b/Misc/NEWS.d/next/Library/2022-03-08-11-34-06.bpo-23325.3VQnfo.rst new file mode 100644 index 0000000..0801cbb --- /dev/null +++ b/Misc/NEWS.d/next/Library/2022-03-08-11-34-06.bpo-23325.3VQnfo.rst @@ -0,0 +1,2 @@ +The :mod:`signal` module no longer assumes that :const:`~signal.SIG_IGN` and +:const:`~signal.SIG_DFL` are small int singletons. diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c index 96881d4..c3a5237 100644 --- a/Modules/signalmodule.c +++ b/Modules/signalmodule.c @@ -174,6 +174,17 @@ get_signal_state(PyObject *module) } +static inline int +compare_handler(PyObject *func, PyObject *dfl_ign_handler) +{ + assert(PyLong_CheckExact(dfl_ign_handler)); + if (!PyLong_CheckExact(func)) { + return 0; + } + // Assume that comparison of two PyLong objects will never fail. + return PyObject_RichCompareBool(func, dfl_ign_handler, Py_EQ) == 1; +} + #ifdef HAVE_GETITIMER /* auxiliary functions for setitimer */ static int @@ -525,21 +536,18 @@ signal_signal_impl(PyObject *module, int signalnum, PyObject *handler) "signal number out of range"); return NULL; } - if (handler == modstate->ignore_handler) { + if (PyCallable_Check(handler)) { + func = signal_handler; + } else if (compare_handler(handler, modstate->ignore_handler)) { func = SIG_IGN; - } - else if (handler == modstate->default_handler) { + } else if (compare_handler(handler, modstate->default_handler)) { func = SIG_DFL; - } - else if (!PyCallable_Check(handler)) { + } else { _PyErr_SetString(tstate, PyExc_TypeError, "signal handler must be signal.SIG_IGN, " "signal.SIG_DFL, or a callable object"); return NULL; } - else { - func = signal_handler; - } /* Check for pending signals before changing signal handler */ if (_PyErr_CheckSignalsTstate(tstate)) { @@ -1736,8 +1744,8 @@ _PySignal_Fini(void) set_handler(signum, NULL); if (func != NULL && func != Py_None - && func != state->default_handler - && func != state->ignore_handler) + && !compare_handler(func, state->default_handler) + && !compare_handler(func, state->ignore_handler)) { PyOS_setsig(signum, SIG_DFL); } @@ -1812,8 +1820,9 @@ _PyErr_CheckSignalsTstate(PyThreadState *tstate) * (see bpo-43406). */ PyObject *func = get_handler(i); - if (func == NULL || func == Py_None || func == state->ignore_handler || - func == state->default_handler) { + if (func == NULL || func == Py_None || + compare_handler(func, state->ignore_handler) || + compare_handler(func, state->default_handler)) { /* No Python signal handler due to aforementioned race condition. * We can't call raise() as it would break the assumption * that PyErr_SetInterrupt() only *simulates* an incoming @@ -1873,7 +1882,8 @@ PyErr_SetInterruptEx(int signum) signal_state_t *state = &signal_global_state; PyObject *func = get_handler(signum); - if (func != state->ignore_handler && func != state->default_handler) { + if (!compare_handler(func, state->ignore_handler) + && !compare_handler(func, state->default_handler)) { trip_signal(signum); } return 0; |