From 3041ff45fe6cd62be471e82cd4a5c9f7436a3745 Mon Sep 17 00:00:00 2001 From: Eric Snow Date: Mon, 16 Jun 2025 17:34:19 -0600 Subject: [PATCH] gh-135443: Sometimes Fall Back to __main__.__dict__ For Globals (gh-135491) For several builtin functions, we now fall back to __main__.__dict__ for the globals when there is no current frame and _PyInterpreterState_IsRunningMain() returns true. This allows those functions to be run with Interpreter.call(). The affected builtins: * exec() * eval() * globals() * locals() * vars() * dir() We take a similar approach with "stateless" functions, which don't use any global variables. (cherry picked from commit a450a0ddec7a2813fb4603f0df406fa33750654a) Co-authored-by: Eric Snow --- Include/internal/pycore_ceval.h | 10 ++ Lib/test/test_interpreters/test_api.py | 107 ++++++++++++++++ Objects/object.c | 20 ++- Python/bltinmodule.c | 163 +++++++++++++++++-------- Python/ceval.c | 119 +++++++++++++++++- Python/crossinterp_data_lookup.h | 24 ++-- Python/import.c | 15 ++- 7 files changed, 392 insertions(+), 66 deletions(-) diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h index 3d8247df31ce32..2c678cd97df79c 100644 --- a/Include/internal/pycore_ceval.h +++ b/Include/internal/pycore_ceval.h @@ -239,6 +239,16 @@ static inline void _Py_LeaveRecursiveCall(void) { extern _PyInterpreterFrame* _PyEval_GetFrame(void); +extern PyObject * _PyEval_GetGlobalsFromRunningMain(PyThreadState *); +extern int _PyEval_EnsureBuiltins( + PyThreadState *, + PyObject *, + PyObject **p_builtins); +extern int _PyEval_EnsureBuiltinsWithModule( + PyThreadState *, + PyObject *, + PyObject **p_builtins); + PyAPI_FUNC(PyObject *)_Py_MakeCoro(PyFunctionObject *func); /* Handle signals, pending calls, GIL drop request diff --git a/Lib/test/test_interpreters/test_api.py b/Lib/test/test_interpreters/test_api.py index 1403cd145b6787..a409c1a691818e 100644 --- a/Lib/test/test_interpreters/test_api.py +++ b/Lib/test/test_interpreters/test_api.py @@ -1414,6 +1414,113 @@ def test_call_invalid(self): with self.assertRaises(interpreters.NotShareableError): interp.call(func, op, 'eggs!') + def test_callable_requires_frame(self): + # There are various functions that require a current frame. + interp = interpreters.create() + for call, expected in [ + ((eval, '[1, 2, 3]'), + [1, 2, 3]), + ((eval, 'sum([1, 2, 3])'), + 6), + ((exec, '...'), + None), + ]: + with self.subTest(str(call)): + res = interp.call(*call) + self.assertEqual(res, expected) + + result_not_pickleable = [ + globals, + locals, + vars, + ] + for func, expectedtype in { + globals: dict, + locals: dict, + vars: dict, + dir: list, + }.items(): + with self.subTest(str(func)): + if func in result_not_pickleable: + with self.assertRaises(interpreters.NotShareableError): + interp.call(func) + else: + res = interp.call(func) + self.assertIsInstance(res, expectedtype) + self.assertIn('__builtins__', res) + + def test_globals_from_builtins(self): + # The builtins exec(), eval(), globals(), locals(), vars(), + # and dir() each runs relative to the target interpreter's + # __main__ module, when called directly. However, + # globals(), locals(), and vars() don't work when called + # directly so we don't check them. + from _frozen_importlib import BuiltinImporter + interp = interpreters.create() + + names = interp.call(dir) + self.assertEqual(names, [ + '__builtins__', + '__doc__', + '__loader__', + '__name__', + '__package__', + '__spec__', + ]) + + values = {name: interp.call(eval, name) + for name in names if name != '__builtins__'} + self.assertEqual(values, { + '__name__': '__main__', + '__doc__': None, + '__spec__': None, # It wasn't imported, so no module spec? + '__package__': None, + '__loader__': BuiltinImporter, + }) + with self.assertRaises(ExecutionFailed): + interp.call(eval, 'spam'), + + interp.call(exec, f'assert dir() == {names}') + + # Update the interpreter's __main__. + interp.prepare_main(spam=42) + expected = names + ['spam'] + + names = interp.call(dir) + self.assertEqual(names, expected) + + value = interp.call(eval, 'spam') + self.assertEqual(value, 42) + + interp.call(exec, f'assert dir() == {expected}, dir()') + + def test_globals_from_stateless_func(self): + # A stateless func, which doesn't depend on any globals, + # doesn't go through pickle, so it runs in __main__. + def set_global(name, value): + globals()[name] = value + + def get_global(name): + return globals().get(name) + + interp = interpreters.create() + + modname = interp.call(get_global, '__name__') + self.assertEqual(modname, '__main__') + + res = interp.call(get_global, 'spam') + self.assertIsNone(res) + + interp.exec('spam = True') + res = interp.call(get_global, 'spam') + self.assertTrue(res) + + interp.call(set_global, 'spam', 42) + res = interp.call(get_global, 'spam') + self.assertEqual(res, 42) + + interp.exec('assert spam == 42, repr(spam)') + def test_call_in_thread(self): interp = interpreters.create() diff --git a/Objects/object.c b/Objects/object.c index 5414b66b0bd8a3..7140520a1bb3e8 100644 --- a/Objects/object.c +++ b/Objects/object.c @@ -1973,9 +1973,25 @@ _dir_locals(void) PyObject *names; PyObject *locals; - locals = _PyEval_GetFrameLocals(); - if (locals == NULL) + if (_PyEval_GetFrame() != NULL) { + locals = _PyEval_GetFrameLocals(); + } + else { + PyThreadState *tstate = _PyThreadState_GET(); + locals = _PyEval_GetGlobalsFromRunningMain(tstate); + if (locals == NULL) { + if (!_PyErr_Occurred(tstate)) { + locals = _PyEval_GetFrameLocals(); + assert(_PyErr_Occurred(tstate)); + } + } + else { + Py_INCREF(locals); + } + } + if (locals == NULL) { return NULL; + } names = PyMapping_Keys(locals); Py_DECREF(locals); diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c index 3d0295ee3883f2..09b6c975383883 100644 --- a/Python/bltinmodule.c +++ b/Python/bltinmodule.c @@ -958,6 +958,7 @@ builtin_eval_impl(PyObject *module, PyObject *source, PyObject *globals, PyObject *locals) /*[clinic end generated code: output=0a0824aa70093116 input=7c7bce5299a89062]*/ { + PyThreadState *tstate = _PyThreadState_GET(); PyObject *result = NULL, *source_copy; const char *str; @@ -971,35 +972,46 @@ builtin_eval_impl(PyObject *module, PyObject *source, PyObject *globals, : "globals must be a dict"); return NULL; } - if (globals == Py_None) { + + int fromframe = 0; + if (globals != Py_None) { + Py_INCREF(globals); + } + else if (_PyEval_GetFrame() != NULL) { + fromframe = 1; globals = PyEval_GetGlobals(); - if (locals == Py_None) { - locals = _PyEval_GetFrameLocals(); - if (locals == NULL) - return NULL; - } - else { - Py_INCREF(locals); - } + assert(globals != NULL); + Py_INCREF(globals); } - else if (locals == Py_None) - locals = Py_NewRef(globals); else { - Py_INCREF(locals); + globals = _PyEval_GetGlobalsFromRunningMain(tstate); + if (globals == NULL) { + if (!_PyErr_Occurred(tstate)) { + PyErr_SetString(PyExc_TypeError, + "eval must be given globals and locals " + "when called without a frame"); + } + return NULL; + } + Py_INCREF(globals); } - if (globals == NULL || locals == NULL) { - PyErr_SetString(PyExc_TypeError, - "eval must be given globals and locals " - "when called without a frame"); - goto error; + if (locals != Py_None) { + Py_INCREF(locals); } - - int r = PyDict_Contains(globals, &_Py_ID(__builtins__)); - if (r == 0) { - r = PyDict_SetItem(globals, &_Py_ID(__builtins__), PyEval_GetBuiltins()); + else if (fromframe) { + locals = _PyEval_GetFrameLocals(); + if (locals == NULL) { + assert(PyErr_Occurred()); + Py_DECREF(globals); + return NULL; + } + } + else { + locals = Py_NewRef(globals); } - if (r < 0) { + + if (_PyEval_EnsureBuiltins(tstate, globals, NULL) < 0) { goto error; } @@ -1040,6 +1052,7 @@ builtin_eval_impl(PyObject *module, PyObject *source, PyObject *globals, } error: + Py_XDECREF(globals); Py_XDECREF(locals); return result; } @@ -1070,29 +1083,44 @@ builtin_exec_impl(PyObject *module, PyObject *source, PyObject *globals, PyObject *locals, PyObject *closure) /*[clinic end generated code: output=7579eb4e7646743d input=25e989b6d87a3a21]*/ { + PyThreadState *tstate = _PyThreadState_GET(); PyObject *v; - if (globals == Py_None) { + int fromframe = 0; + if (globals != Py_None) { + Py_INCREF(globals); + } + else if (_PyEval_GetFrame() != NULL) { + fromframe = 1; globals = PyEval_GetGlobals(); - if (locals == Py_None) { - locals = _PyEval_GetFrameLocals(); - if (locals == NULL) - return NULL; - } - else { - Py_INCREF(locals); + assert(globals != NULL); + Py_INCREF(globals); + } + else { + globals = _PyEval_GetGlobalsFromRunningMain(tstate); + if (globals == NULL) { + if (!_PyErr_Occurred(tstate)) { + PyErr_SetString(PyExc_SystemError, + "globals and locals cannot be NULL"); + } + goto error; } - if (!globals || !locals) { - PyErr_SetString(PyExc_SystemError, - "globals and locals cannot be NULL"); + Py_INCREF(globals); + } + + if (locals != Py_None) { + Py_INCREF(locals); + } + else if (fromframe) { + locals = _PyEval_GetFrameLocals(); + if (locals == NULL) { + assert(PyErr_Occurred()); + Py_DECREF(globals); return NULL; } } - else if (locals == Py_None) { - locals = Py_NewRef(globals); - } else { - Py_INCREF(locals); + locals = Py_NewRef(globals); } if (!PyDict_Check(globals)) { @@ -1106,11 +1134,8 @@ builtin_exec_impl(PyObject *module, PyObject *source, PyObject *globals, Py_TYPE(locals)->tp_name); goto error; } - int r = PyDict_Contains(globals, &_Py_ID(__builtins__)); - if (r == 0) { - r = PyDict_SetItem(globals, &_Py_ID(__builtins__), PyEval_GetBuiltins()); - } - if (r < 0) { + + if (_PyEval_EnsureBuiltins(tstate, globals, NULL) < 0) { goto error; } @@ -1187,11 +1212,13 @@ builtin_exec_impl(PyObject *module, PyObject *source, PyObject *globals, } if (v == NULL) goto error; + Py_DECREF(globals); Py_DECREF(locals); Py_DECREF(v); Py_RETURN_NONE; error: + Py_XDECREF(globals); Py_XDECREF(locals); return NULL; } @@ -1241,10 +1268,21 @@ static PyObject * builtin_globals_impl(PyObject *module) /*[clinic end generated code: output=e5dd1527067b94d2 input=9327576f92bb48ba]*/ { - PyObject *d; - - d = PyEval_GetGlobals(); - return Py_XNewRef(d); + PyObject *globals; + if (_PyEval_GetFrame() != NULL) { + globals = PyEval_GetGlobals(); + assert(globals != NULL); + return Py_NewRef(globals); + } + PyThreadState *tstate = _PyThreadState_GET(); + globals = _PyEval_GetGlobalsFromRunningMain(tstate); + if (globals == NULL) { + if (_PyErr_Occurred(tstate)) { + return NULL; + } + Py_RETURN_NONE; + } + return Py_NewRef(globals); } @@ -1888,7 +1926,21 @@ static PyObject * builtin_locals_impl(PyObject *module) /*[clinic end generated code: output=b46c94015ce11448 input=7874018d478d5c4b]*/ { - return _PyEval_GetFrameLocals(); + PyObject *locals; + if (_PyEval_GetFrame() != NULL) { + locals = _PyEval_GetFrameLocals(); + assert(locals != NULL || PyErr_Occurred()); + return locals; + } + PyThreadState *tstate = _PyThreadState_GET(); + locals = _PyEval_GetGlobalsFromRunningMain(tstate); + if (locals == NULL) { + if (_PyErr_Occurred(tstate)) { + return NULL; + } + Py_RETURN_NONE; + } + return Py_NewRef(locals); } @@ -2624,7 +2676,22 @@ builtin_vars(PyObject *self, PyObject *args) if (!PyArg_UnpackTuple(args, "vars", 0, 1, &v)) return NULL; if (v == NULL) { - d = _PyEval_GetFrameLocals(); + if (_PyEval_GetFrame() != NULL) { + d = _PyEval_GetFrameLocals(); + } + else { + PyThreadState *tstate = _PyThreadState_GET(); + d = _PyEval_GetGlobalsFromRunningMain(tstate); + if (d == NULL) { + if (!_PyErr_Occurred(tstate)) { + d = _PyEval_GetFrameLocals(); + assert(_PyErr_Occurred(tstate)); + } + } + else { + Py_INCREF(d); + } + } } else { if (PyObject_GetOptionalAttr(v, &_Py_ID(__dict__), &d) == 0) { diff --git a/Python/ceval.c b/Python/ceval.c index d1b6b9f1a1a35f..12d9011f5c7ee2 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -2732,10 +2732,9 @@ _PyEval_GetFrameLocals(void) return locals; } -PyObject * -PyEval_GetGlobals(void) +static PyObject * +_PyEval_GetGlobals(PyThreadState *tstate) { - PyThreadState *tstate = _PyThreadState_GET(); _PyInterpreterFrame *current_frame = _PyThreadState_GetFrame(tstate); if (current_frame == NULL) { return NULL; @@ -2743,6 +2742,120 @@ PyEval_GetGlobals(void) return current_frame->f_globals; } +PyObject * +PyEval_GetGlobals(void) +{ + PyThreadState *tstate = _PyThreadState_GET(); + return _PyEval_GetGlobals(tstate); +} + +PyObject * +_PyEval_GetGlobalsFromRunningMain(PyThreadState *tstate) +{ + if (!_PyInterpreterState_IsRunningMain(tstate->interp)) { + return NULL; + } + PyObject *mod = _Py_GetMainModule(tstate); + if (_Py_CheckMainModule(mod) < 0) { + Py_XDECREF(mod); + return NULL; + } + PyObject *globals = PyModule_GetDict(mod); // borrowed + Py_DECREF(mod); + return globals; +} + +static PyObject * +get_globals_builtins(PyObject *globals) +{ + PyObject *builtins = NULL; + if (PyDict_Check(globals)) { + if (PyDict_GetItemRef(globals, &_Py_ID(__builtins__), &builtins) < 0) { + return NULL; + } + } + else { + if (PyMapping_GetOptionalItem( + globals, &_Py_ID(__builtins__), &builtins) < 0) + { + return NULL; + } + } + return builtins; +} + +static int +set_globals_builtins(PyObject *globals, PyObject *builtins) +{ + if (PyDict_Check(globals)) { + if (PyDict_SetItem(globals, &_Py_ID(__builtins__), builtins) < 0) { + return -1; + } + } + else { + if (PyObject_SetItem(globals, &_Py_ID(__builtins__), builtins) < 0) { + return -1; + } + } + return 0; +} + +int +_PyEval_EnsureBuiltins(PyThreadState *tstate, PyObject *globals, + PyObject **p_builtins) +{ + PyObject *builtins = get_globals_builtins(globals); + if (builtins == NULL) { + if (_PyErr_Occurred(tstate)) { + return -1; + } + builtins = PyEval_GetBuiltins(); // borrowed + if (builtins == NULL) { + assert(_PyErr_Occurred(tstate)); + return -1; + } + Py_INCREF(builtins); + if (set_globals_builtins(globals, builtins) < 0) { + Py_DECREF(builtins); + return -1; + } + } + if (p_builtins != NULL) { + *p_builtins = builtins; + } + else { + Py_DECREF(builtins); + } + return 0; +} + +int +_PyEval_EnsureBuiltinsWithModule(PyThreadState *tstate, PyObject *globals, + PyObject **p_builtins) +{ + PyObject *builtins = get_globals_builtins(globals); + if (builtins == NULL) { + if (_PyErr_Occurred(tstate)) { + return -1; + } + builtins = PyImport_ImportModuleLevel("builtins", NULL, NULL, NULL, 0); + if (builtins == NULL) { + return -1; + } + if (set_globals_builtins(globals, builtins) < 0) { + Py_DECREF(builtins); + return -1; + } + } + if (p_builtins != NULL) { + *p_builtins = builtins; + } + else { + Py_DECREF(builtins); + } + return 0; +} + PyObject* PyEval_GetFrameLocals(void) { diff --git a/Python/crossinterp_data_lookup.h b/Python/crossinterp_data_lookup.h index 6d0b93eb82ac1e..c3c76ae8d9a289 100644 --- a/Python/crossinterp_data_lookup.h +++ b/Python/crossinterp_data_lookup.h @@ -722,16 +722,26 @@ _PyFunction_FromXIData(_PyXIData_t *xidata) return NULL; } // Create a new function. + // For stateless functions (no globals) we use __main__ as __globals__, + // just like we do for builtins like exec(). assert(PyCode_Check(code)); - PyObject *globals = PyDict_New(); + PyThreadState *tstate = _PyThreadState_GET(); + PyObject *globals = _PyEval_GetGlobalsFromRunningMain(tstate); // borrowed if (globals == NULL) { - Py_DECREF(code); - return NULL; + if (_PyErr_Occurred(tstate)) { + Py_DECREF(code); + return NULL; + } + globals = PyDict_New(); + if (globals == NULL) { + Py_DECREF(code); + return NULL; + } } - PyThreadState *tstate = _PyThreadState_GET(); - if (PyDict_SetItem(globals, &_Py_ID(__builtins__), - tstate->interp->builtins) < 0) - { + else { + Py_INCREF(globals); + } + if (_PyEval_EnsureBuiltins(tstate, globals, NULL) < 0) { Py_DECREF(code); Py_DECREF(globals); return NULL; diff --git a/Python/import.c b/Python/import.c index d67bbb703525d1..add78534606bf0 100644 --- a/Python/import.c +++ b/Python/import.c @@ -3958,25 +3958,28 @@ PyImport_Import(PyObject *module_name) } /* Get the builtins from current globals */ - globals = PyEval_GetGlobals(); + globals = PyEval_GetGlobals(); // borrowed if (globals != NULL) { Py_INCREF(globals); + // XXX Use _PyEval_EnsureBuiltins()? builtins = PyObject_GetItem(globals, &_Py_ID(__builtins__)); if (builtins == NULL) { // XXX Fall back to interp->builtins or sys.modules['builtins']? goto err; } } + else if (_PyErr_Occurred(tstate)) { + goto err; + } else { /* No globals -- use standard builtins, and fake globals */ - builtins = PyImport_ImportModuleLevel("builtins", - NULL, NULL, NULL, 0); - if (builtins == NULL) { + globals = PyDict_New(); + if (globals == NULL) { goto err; } - globals = Py_BuildValue("{OO}", &_Py_ID(__builtins__), builtins); - if (globals == NULL) + if (_PyEval_EnsureBuiltinsWithModule(tstate, globals, &builtins) < 0) { goto err; + } } /* Get the __import__ function from the builtins */