#ifndef Py_BUILD_CORE_BUILTIN

# define Py_BUILD_CORE_MODULE 1

#include "Python.h"

#include "pycore_frame.h"

#include "pycore_pystate.h" // _PyThreadState_GET()

#include "pycore_interpreteridobject.h"

#define MODULE_NAME "_xxsubinterpreters"

static char *

_copy_raw_string(PyObject *strobj)

{

const char *str = PyUnicode_AsUTF8(strobj);

if (str == NULL) {

return NULL;

}

char *copied = PyMem_Malloc(strlen(str)+1);

if (copied == NULL) {

PyErr_NoMemory();

return NULL;

}

strcpy(copied, str);

return copied;

}

static PyInterpreterState *

_get_current_interp(void)

{

// PyInterpreterState_Get() aborts if lookup fails, so don't need

// to check the result for NULL.

return PyInterpreterState_Get();

}

static PyObject *

add_new_exception(PyObject *mod, const char *name, PyObject *base)

{

assert(!PyObject_HasAttrString(mod, name));

PyObject *exctype = PyErr_NewException(name, base, NULL);

if (exctype == NULL) {

return NULL;

}

int res = PyModule_AddType(mod, (PyTypeObject *)exctype);

if (res < 0) {

Py_DECREF(exctype);

return NULL;

}

return exctype;

}

#define ADD_NEW_EXCEPTION(MOD, NAME, BASE) \

add_new_exception(MOD, MODULE_NAME "." Py_STRINGIFY(NAME), BASE)

static int

_release_xid_data(_PyCrossInterpreterData *data, int ignoreexc)

{

PyObject *exctype, *excval, *exctb;

if (ignoreexc) {

PyErr_Fetch(&exctype, &excval, &exctb);

}

int res = _PyCrossInterpreterData_Release(data);

if (res < 0) {

// XXX Fix this!

/* The owning interpreter is already destroyed.

_PyCrossInterpreterData_Clear(NULL, data);

if (ignoreexc) {

// XXX Emit a warning?

PyErr_Clear();

}

}

if (ignoreexc) {

PyErr_Restore(exctype, excval, exctb);

}

return res;

}

typedef struct {

/* exceptions */

PyObject *RunFailedError;

} module_state;

static inline module_state *

get_module_state(PyObject *mod)

{

assert(mod != NULL);

module_state *state = PyModule_GetState(mod);

assert(state != NULL);

return state;

}

static int

traverse_module_state(module_state *state, visitproc visit, void *arg)

{

/* exceptions */

Py_VISIT(state->RunFailedError);

return 0;

}

static int

clear_module_state(module_state *state)

{

/* exceptions */

Py_CLEAR(state->RunFailedError);

return 0;

}

struct _sharednsitem {

char *name;

_PyCrossInterpreterData data;

};

static void _sharednsitem_clear(struct _sharednsitem *); // forward

static int

_sharednsitem_init(struct _sharednsitem *item, PyObject *key, PyObject *value)

{

item->name = _copy_raw_string(key);

if (item->name == NULL) {

return -1;

}

if (_PyObject_GetCrossInterpreterData(value, &item->data) != 0) {

_sharednsitem_clear(item);

return -1;

}

return 0;

}

static void

_sharednsitem_clear(struct _sharednsitem *item)

{

if (item->name != NULL) {

PyMem_Free(item->name);

item->name = NULL;

}

(void)_release_xid_data(&item->data, 1);

}

static int

_sharednsitem_apply(struct _sharednsitem *item, PyObject *ns)

{

PyObject *name = PyUnicode_FromString(item->name);

if (name == NULL) {

return -1;

}

PyObject *value = _PyCrossInterpreterData_NewObject(&item->data);

if (value == NULL) {

Py_DECREF(name);

return -1;

}

int res = PyDict_SetItem(ns, name, value);

Py_DECREF(name);

Py_DECREF(value);

return res;

}

typedef struct _sharedns {

Py_ssize_t len;

struct _sharednsitem* items;

} _sharedns;

static _sharedns *

_sharedns_new(Py_ssize_t len)

{

_sharedns *shared = PyMem_NEW(_sharedns, 1);

if (shared == NULL) {

PyErr_NoMemory();

return NULL;

}

shared->len = len;

shared->items = PyMem_NEW(struct _sharednsitem, len);

if (shared->items == NULL) {

PyErr_NoMemory();

PyMem_Free(shared);

return NULL;

}

return shared;

}

static void

_sharedns_free(_sharedns *shared)

{

for (Py_ssize_t i=0; i < shared->len; i++) {

_sharednsitem_clear(&shared->items[i]);

}

PyMem_Free(shared->items);

PyMem_Free(shared);

}

static _sharedns *

_get_shared_ns(PyObject *shareable)

{

if (shareable == NULL || shareable == Py_None) {

return NULL;

}

Py_ssize_t len = PyDict_Size(shareable);

if (len == 0) {

return NULL;

}

_sharedns *shared = _sharedns_new(len);

if (shared == NULL) {

return NULL;

}

Py_ssize_t pos = 0;

for (Py_ssize_t i=0; i < len; i++) {

PyObject *key, *value;

if (PyDict_Next(shareable, &pos, &key, &value) == 0) {

break;

}

if (_sharednsitem_init(&shared->items[i], key, value) != 0) {

break;

}

}

if (PyErr_Occurred()) {

_sharedns_free(shared);

return NULL;

}

return shared;

}

static int

_sharedns_apply(_sharedns *shared, PyObject *ns)

{

for (Py_ssize_t i=0; i < shared->len; i++) {

if (_sharednsitem_apply(&shared->items[i], ns) != 0) {

return -1;

}

}

return 0;

}

typedef struct _sharedexception {

char *name;

char *msg;

} _sharedexception;

static _sharedexception *

_sharedexception_new(void)

{

_sharedexception *err = PyMem_NEW(_sharedexception, 1);

if (err == NULL) {

PyErr_NoMemory();

return NULL;

}

err->name = NULL;

err->msg = NULL;

return err;

}

static void

_sharedexception_clear(_sharedexception *exc)

{

if (exc->name != NULL) {

PyMem_Free(exc->name);

}

if (exc->msg != NULL) {

PyMem_Free(exc->msg);

}

}

static void

_sharedexception_free(_sharedexception *exc)

{

_sharedexception_clear(exc);

PyMem_Free(exc);

}

static _sharedexception *

_sharedexception_bind(PyObject *exctype, PyObject *exc, PyObject *tb)

{

assert(exctype != NULL);

char *failure = NULL;

_sharedexception *err = _sharedexception_new();

if (err == NULL) {

goto finally;

}

PyObject *name = PyUnicode_FromFormat("%S", exctype);

if (name == NULL) {

failure = "unable to format exception type name";

goto finally;

}

err->name = _copy_raw_string(name);

Py_DECREF(name);

if (err->name == NULL) {

if (PyErr_ExceptionMatches(PyExc_MemoryError)) {

failure = "out of memory copying exception type name";

} else {

failure = "unable to encode and copy exception type name";

}

goto finally;

}

if (exc != NULL) {

PyObject *msg = PyUnicode_FromFormat("%S", exc);

if (msg == NULL) {

failure = "unable to format exception message";

goto finally;

}

err->msg = _copy_raw_string(msg);

Py_DECREF(msg);

if (err->msg == NULL) {

if (PyErr_ExceptionMatches(PyExc_MemoryError)) {

failure = "out of memory copying exception message";

} else {

failure = "unable to encode and copy exception message";

}

goto finally;

}

}

finally:

if (failure != NULL) {

PyErr_Clear();

if (err->name != NULL) {

PyMem_Free(err->name);

err->name = NULL;

}

err->msg = failure;

}

return err;

}

static void

_sharedexception_apply(_sharedexception *exc, PyObject *wrapperclass)

{

if (exc->name != NULL) {

if (exc->msg != NULL) {

PyErr_Format(wrapperclass, "%s: %s", exc->name, exc->msg);

}

else {

PyErr_SetString(wrapperclass, exc->name);

}

}

else if (exc->msg != NULL) {

PyErr_SetString(wrapperclass, exc->msg);

}

else {

PyErr_SetNone(wrapperclass);

}

}

static int

exceptions_init(PyObject *mod)

{

module_state *state = get_module_state(mod);

if (state == NULL) {

return -1;

}

#define ADD(NAME, BASE) \

do { \

assert(state->NAME == NULL); \

state->NAME = ADD_NEW_EXCEPTION(mod, NAME, BASE); \

if (state->NAME == NULL) { \

return -1; \

} \

} while (0)

// An uncaught exception came out of interp_run_string().

ADD(RunFailedError, PyExc_RuntimeError);

#undef ADD

return 0;

}

static int

_is_running(PyInterpreterState *interp)

{

PyThreadState *tstate = PyInterpreterState_ThreadHead(interp);

if (PyThreadState_Next(tstate) != NULL) {

PyErr_SetString(PyExc_RuntimeError,

"interpreter has more than one thread");

return -1;

}

assert(!PyErr_Occurred());

_PyInterpreterFrame *frame = tstate->cframe->current_frame;

if (frame == NULL) {

return 0;

}

return 1;

}

static int

_ensure_not_running(PyInterpreterState *interp)

{

int is_running = _is_running(interp);

if (is_running < 0) {

return -1;

}

if (is_running) {

PyErr_Format(PyExc_RuntimeError, "interpreter already running");

return -1;

}

return 0;

}

static int

_run_script(PyInterpreterState *interp, const char *codestr,

_sharedns *shared, _sharedexception **exc)

{

PyObject *exctype = NULL;

PyObject *excval = NULL;

PyObject *tb = NULL;

PyObject *main_mod = _PyInterpreterState_GetMainModule(interp);

if (main_mod == NULL) {

goto error;

}

PyObject *ns = PyModule_GetDict(main_mod); // borrowed

Py_DECREF(main_mod);

if (ns == NULL) {

goto error;

}

Py_INCREF(ns);

// Apply the cross-interpreter data.

if (shared != NULL) {

if (_sharedns_apply(shared, ns) != 0) {

Py_DECREF(ns);

goto error;

}

}

// Run the string (see PyRun_SimpleStringFlags).

PyObject *result = PyRun_StringFlags(codestr, Py_file_input, ns, ns, NULL);

Py_DECREF(ns);

if (result == NULL) {

goto error;

}

else {

Py_DECREF(result); // We throw away the result.

}

*exc = NULL;

return 0;

error:

PyErr_Fetch(&exctype, &excval, &tb);

_sharedexception *sharedexc = _sharedexception_bind(exctype, excval, tb);

Py_XDECREF(exctype);

Py_XDECREF(excval);

Py_XDECREF(tb);

if (sharedexc == NULL) {

fprintf(stderr, "RunFailedError: script raised an uncaught exception");

PyErr_Clear();

sharedexc = NULL;

}

else {

assert(!PyErr_Occurred());

}

*exc = sharedexc;

return -1;

}

static int

_run_script_in_interpreter(PyObject *mod, PyInterpreterState *interp,

const char *codestr, PyObject *shareables)

{

if (_ensure_not_running(interp) < 0) {

return -1;

}

module_state *state = get_module_state(mod);

_sharedns *shared = _get_shared_ns(shareables);

if (shared == NULL && PyErr_Occurred()) {

return -1;

}

// Switch to interpreter.

PyThreadState *save_tstate = NULL;

if (interp != PyInterpreterState_Get()) {

// XXX Using the "head" thread isn't strictly correct.

PyThreadState *tstate = PyInterpreterState_ThreadHead(interp);

// XXX Possible GILState issues?

save_tstate = PyThreadState_Swap(tstate);

}

// Run the script.

_sharedexception *exc = NULL;

int result = _run_script(interp, codestr, shared, &exc);

// Switch back.

if (save_tstate != NULL) {

PyThreadState_Swap(save_tstate);

}

// Propagate any exception out to the caller.

if (exc != NULL) {

assert(state != NULL);

_sharedexception_apply(exc, state->RunFailedError);

_sharedexception_free(exc);

}

else if (result != 0) {

// We were unable to allocate a shared exception.

PyErr_NoMemory();

}

if (shared != NULL) {

_sharedns_free(shared);

}

return result;

}

static PyObject *

interp_create(PyObject *self, PyObject *args, PyObject *kwds)

{

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_GET();

const _PyInterpreterConfig config = isolated

? (_PyInterpreterConfig)_PyInterpreterConfig_INIT

: (_PyInterpreterConfig)_PyInterpreterConfig_LEGACY_INIT;

// XXX Possible GILState issues?

PyThreadState *tstate = _Py_NewInterpreterFromConfig(&config);

PyThreadState_Swap(save_tstate);

if (tstate == NULL) {

/* Since no new thread state was created, there is no exception to

PyErr_SetString(PyExc_RuntimeError, "interpreter creation failed");

return NULL;

}

PyInterpreterState *interp = PyThreadState_GetInterpreter(tstate);

PyObject *idobj = _PyInterpreterState_GetIDObject(interp);

if (idobj == NULL) {

// XXX Possible GILState issues?

save_tstate = PyThreadState_Swap(tstate);

Py_EndInterpreter(tstate);

PyThreadState_Swap(save_tstate);

return NULL;

}

_PyInterpreterState_RequireIDRef(interp, 1);

return idobj;

}

PyDoc_STRVAR(create_doc,

Create a new interpreter and return a unique generated ID.");

static PyObject *

interp_destroy(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kwlist[] = {"id", NULL};

PyObject *id;

// XXX Use "L" for id?

if (!PyArg_ParseTupleAndKeywords(args, kwds,

"O:destroy", kwlist, &id)) {

return NULL;

}

// Look up the interpreter.

PyInterpreterState *interp = _PyInterpreterID_LookUp(id);

if (interp == NULL) {

return NULL;

}

// Ensure we don't try to destroy the current interpreter.

PyInterpreterState *current = _get_current_interp();

if (current == NULL) {

return NULL;

}

if (interp == current) {

PyErr_SetString(PyExc_RuntimeError,

"cannot destroy the current interpreter");

return NULL;

}

// Ensure the interpreter isn't running.

/* XXX We *could* support destroying a running interpreter but

if (_ensure_not_running(interp) < 0) {

return NULL;

}

// Destroy the interpreter.

PyThreadState *tstate = PyInterpreterState_ThreadHead(interp);

// XXX Possible GILState issues?

PyThreadState *save_tstate = PyThreadState_Swap(tstate);

Py_EndInterpreter(tstate);

PyThreadState_Swap(save_tstate);

Py_RETURN_NONE;

}

PyDoc_STRVAR(destroy_doc,

So does an unrecognized ID.");

static PyObject *

interp_list_all(PyObject *self, PyObject *Py_UNUSED(ignored))

{

PyObject *ids, *id;

PyInterpreterState *interp;

ids = PyList_New(0);

if (ids == NULL) {

return NULL;

}

interp = PyInterpreterState_Head();

while (interp != NULL) {

id = _PyInterpreterState_GetIDObject(interp);

if (id == NULL) {

Py_DECREF(ids);

return NULL;

}

// insert at front of list

int res = PyList_Insert(ids, 0, id);

Py_DECREF(id);

if (res < 0) {

Py_DECREF(ids);

return NULL;

}

interp = PyInterpreterState_Next(interp);

}

return ids;

}

PyDoc_STRVAR(list_all_doc,

Return a list containing the ID of every existing interpreter.");

static PyObject *

interp_get_current(PyObject *self, PyObject *Py_UNUSED(ignored))

{

PyInterpreterState *interp =_get_current_interp();

if (interp == NULL) {

return NULL;

}

return _PyInterpreterState_GetIDObject(interp);

}

PyDoc_STRVAR(get_current_doc,

Return the ID of current interpreter.");

static PyObject *

interp_get_main(PyObject *self, PyObject *Py_UNUSED(ignored))

{

// Currently, 0 is always the main interpreter.

int64_t id = 0;

return _PyInterpreterID_New(id);

}

PyDoc_STRVAR(get_main_doc,

Return the ID of main interpreter.");

static PyObject *

interp_run_string(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kwlist[] = {"id", "script", "shared", NULL};

PyObject *id, *code;

PyObject *shared = NULL;

if (!PyArg_ParseTupleAndKeywords(args, kwds,

"OU|O:run_string", kwlist,

&id, &code, &shared)) {

return NULL;

}

// Look up the interpreter.

PyInterpreterState *interp = _PyInterpreterID_LookUp(id);

if (interp == NULL) {

return NULL;

}

// Extract code.

Py_ssize_t size;

const char *codestr = PyUnicode_AsUTF8AndSize(code, &size);

if (codestr == NULL) {

return NULL;

}

if (strlen(codestr) != (size_t)size) {

PyErr_SetString(PyExc_ValueError,

"source code string cannot contain null bytes");

return NULL;

}

// Run the code in the interpreter.

if (_run_script_in_interpreter(self, interp, codestr, shared) != 0) {

return NULL;

}

Py_RETURN_NONE;

}

PyDoc_STRVAR(run_string_doc,

See PyRun_SimpleStrings.");

static PyObject *

object_is_shareable(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kwlist[] = {"obj", NULL};

PyObject *obj;

if (!PyArg_ParseTupleAndKeywords(args, kwds,

"O:is_shareable", kwlist, &obj)) {

return NULL;

}

if (_PyObject_CheckCrossInterpreterData(obj) == 0) {

Py_RETURN_TRUE;

}

PyErr_Clear();

Py_RETURN_FALSE;

}

PyDoc_STRVAR(is_shareable_doc,

False otherwise.");

static PyObject *

interp_is_running(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kwlist[] = {"id", NULL};

PyObject *id;

if (!PyArg_ParseTupleAndKeywords(args, kwds,

"O:is_running", kwlist, &id)) {

return NULL;

}

PyInterpreterState *interp = _PyInterpreterID_LookUp(id);

if (interp == NULL) {

return NULL;

}

int is_running = _is_running(interp);

if (is_running < 0) {

return NULL;

}

if (is_running) {

Py_RETURN_TRUE;

}

Py_RETURN_FALSE;

}

PyDoc_STRVAR(is_running_doc,

Return whether or not the identified interpreter is running.");

static PyMethodDef module_functions[] = {

{"create", _PyCFunction_CAST(interp_create),

METH_VARARGS | METH_KEYWORDS, create_doc},

{"destroy", _PyCFunction_CAST(interp_destroy),

METH_VARARGS | METH_KEYWORDS, destroy_doc},

{"list_all", interp_list_all,

METH_NOARGS, list_all_doc},

{"get_current", interp_get_current,

METH_NOARGS, get_current_doc},

{"get_main", interp_get_main,

METH_NOARGS, get_main_doc},

{"is_running", _PyCFunction_CAST(interp_is_running),

METH_VARARGS | METH_KEYWORDS, is_running_doc},

{"run_string", _PyCFunction_CAST(interp_run_string),

METH_VARARGS | METH_KEYWORDS, run_string_doc},

{"is_shareable", _PyCFunction_CAST(object_is_shareable),

METH_VARARGS | METH_KEYWORDS, is_shareable_doc},

{NULL, NULL} /* sentinel */

};

PyDoc_STRVAR(module_doc,

The 'interpreters' module provides a more convenient interface.");

static int

module_exec(PyObject *mod)

{

/* Add exception types */

if (exceptions_init(mod) != 0) {

goto error;

}

// PyInterpreterID

if (PyModule_AddType(mod, &_PyInterpreterID_Type) < 0) {

goto error;

}

return 0;

error:

return -1;

}

static struct PyModuleDef_Slot module_slots[] = {

{Py_mod_exec, module_exec},

{0, NULL},

};

static int

module_traverse(PyObject *mod, visitproc visit, void *arg)

{

module_state *state = get_module_state(mod);

assert(state != NULL);

traverse_module_state(state, visit, arg);

return 0;

}

static int

module_clear(PyObject *mod)

{

module_state *state = get_module_state(mod);

assert(state != NULL);

clear_module_state(state);

return 0;

}

static void

module_free(void *mod)

{

module_state *state = get_module_state(mod);

assert(state != NULL);

clear_module_state(state);

}

static struct PyModuleDef moduledef = {

.m_base = PyModuleDef_HEAD_INIT,

.m_name = MODULE_NAME,

.m_doc = module_doc,

.m_size = sizeof(module_state),

.m_methods = module_functions,

.m_slots = module_slots,

.m_traverse = module_traverse,

.m_clear = module_clear,

.m_free = (freefunc)module_free,

};

PyInit__xxsubinterpreters(void)

{

return PyModuleDef_Init(&moduledef);

}