bpo-40453: Add PyConfig._isolated_subinterpreter (GH-19820)
An isolated subinterpreter cannot spawn threads, spawn a child
process or call os.fork().
* Add private _Py_NewInterpreter(isolated_subinterpreter) function.
* Add isolated=True keyword-only parameter to
_xxsubinterpreters.create().
* Allow again os.fork() in "non-isolated" subinterpreters.
diff --git a/Modules/_posixsubprocess.c b/Modules/_posixsubprocess.c
index 60dd78d..add2962 100644
--- a/Modules/_posixsubprocess.c
+++ b/Modules/_posixsubprocess.c
@@ -663,6 +663,14 @@
return NULL;
}
+ PyInterpreterState *interp = PyInterpreterState_Get();
+ const PyConfig *config = _PyInterpreterState_GetConfig(interp);
+ if (config->_isolated_interpreter) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "subprocess not supported for isolated subinterpreters");
+ return NULL;
+ }
+
/* We need to call gc.disable() when we'll be calling preexec_fn */
if (preexec_fn != Py_None) {
PyObject *result;
diff --git a/Modules/_threadmodule.c b/Modules/_threadmodule.c
index b3d90b2..77baba4 100644
--- a/Modules/_threadmodule.c
+++ b/Modules/_threadmodule.c
@@ -1085,6 +1085,14 @@
"optional 3rd arg must be a dictionary");
return NULL;
}
+
+ PyInterpreterState *interp = _PyInterpreterState_GET();
+ if (interp->config._isolated_interpreter) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "thread is not supported for isolated subinterpreters");
+ return NULL;
+ }
+
boot = PyMem_NEW(struct bootstate, 1);
if (boot == NULL)
return PyErr_NoMemory();
diff --git a/Modules/_winapi.c b/Modules/_winapi.c
index 1b28adb..e1672c4 100644
--- a/Modules/_winapi.c
+++ b/Modules/_winapi.c
@@ -1080,6 +1080,14 @@
return NULL;
}
+ PyInterpreterState *interp = PyInterpreterState_Get();
+ const PyConfig *config = _PyInterpreterState_GetConfig(interp);
+ if (config->_isolated_interpreter) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "subprocess not supported for isolated subinterpreters");
+ return NULL;
+ }
+
ZeroMemory(&si, sizeof(si));
si.StartupInfo.cb = sizeof(si);
diff --git a/Modules/_xxsubinterpretersmodule.c b/Modules/_xxsubinterpretersmodule.c
index 15e8055..de11c09 100644
--- a/Modules/_xxsubinterpretersmodule.c
+++ b/Modules/_xxsubinterpretersmodule.c
@@ -1999,16 +1999,20 @@
}
static PyObject *
-interp_create(PyObject *self, PyObject *args)
+interp_create(PyObject *self, PyObject *args, PyObject *kwds)
{
- if (!PyArg_UnpackTuple(args, "create", 0, 0)) {
+
+ static char *kwlist[] = {"isolated", NULL};
+ int isolated = 1;
+ if (!PyArg_ParseTupleAndKeywords(args, kwds, "|$i:create", kwlist,
+ &isolated)) {
return NULL;
}
// Create and initialize the new interpreter.
PyThreadState *save_tstate = PyThreadState_Swap(NULL);
// XXX Possible GILState issues?
- PyThreadState *tstate = Py_NewInterpreter();
+ PyThreadState *tstate = _Py_NewInterpreter(isolated);
PyThreadState_Swap(save_tstate);
if (tstate == NULL) {
/* Since no new thread state was created, there is no exception to
@@ -2547,8 +2551,8 @@
}
static PyMethodDef module_functions[] = {
- {"create", (PyCFunction)interp_create,
- METH_VARARGS, create_doc},
+ {"create", (PyCFunction)(void(*)(void))interp_create,
+ METH_VARARGS | METH_KEYWORDS, create_doc},
{"destroy", (PyCFunction)(void(*)(void))interp_destroy,
METH_VARARGS | METH_KEYWORDS, destroy_doc},
{"list_all", interp_list_all,
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 3d3f6ac..0163b07 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -6243,9 +6243,10 @@
/*[clinic end generated code: output=3626c81f98985d49 input=13c956413110eeaa]*/
{
pid_t pid;
-
- if (_PyInterpreterState_GET() != PyInterpreterState_Main()) {
- PyErr_SetString(PyExc_RuntimeError, "fork not supported for subinterpreters");
+ PyInterpreterState *interp = _PyInterpreterState_GET();
+ if (interp->config._isolated_interpreter) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "fork not supported for isolated subinterpreters");
return NULL;
}
if (PySys_Audit("os.fork", NULL) < 0) {