#include "Python.h"

#include "pycore_call.h" // _PyObject_CallNoArgsTstate()

#include "pycore_ceval.h" // _PyEval_EvalFrame()

#include "pycore_object.h" // _PyObject_GC_TRACK()

#include "pycore_pyerrors.h" // _PyErr_Occurred()

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

#include "pycore_tuple.h" // _PyTuple_ITEMS()

#include "frameobject.h" // _PyFrame_New_NoTrack()

static PyObject *const *

_PyStack_UnpackDict(PyThreadState *tstate,

PyObject *const *args, Py_ssize_t nargs,

PyObject *kwargs, PyObject **p_kwnames);

static void

_PyStack_UnpackDict_Free(PyObject *const *stack, Py_ssize_t nargs,

PyObject *kwnames);

static PyObject *

null_error(PyThreadState *tstate)

{

if (!_PyErr_Occurred(tstate)) {

_PyErr_SetString(tstate, PyExc_SystemError,

"null argument to internal routine");

}

return NULL;

}

PyObject*

_Py_CheckFunctionResult(PyThreadState *tstate, PyObject *callable,

PyObject *result, const char *where)

{

assert((callable != NULL) ^ (where != NULL));

if (result == NULL) {

if (!_PyErr_Occurred(tstate)) {

if (callable)

_PyErr_Format(tstate, PyExc_SystemError,

"%R returned NULL without setting an exception",

callable);

else

_PyErr_Format(tstate, PyExc_SystemError,

"%s returned NULL without setting an exception",

where);

#ifdef Py_DEBUG

/* Ensure that the bug is caught in debug mode.

Py_FatalError() logs the SystemError exception raised above. */

Py_FatalError("a function returned NULL without setting an exception");

#endif

return NULL;

}

}

else {

if (_PyErr_Occurred(tstate)) {

Py_DECREF(result);

if (callable) {

_PyErr_FormatFromCauseTstate(

tstate, PyExc_SystemError,

"%R returned a result with an exception set", callable);

}

else {

_PyErr_FormatFromCauseTstate(

tstate, PyExc_SystemError,

"%s returned a result with an exception set", where);

}

#ifdef Py_DEBUG

/* Ensure that the bug is caught in debug mode.

Py_FatalError() logs the SystemError exception raised above. */

Py_FatalError("a function returned a result with an exception set");

#endif

return NULL;

}

}

return result;

}

int

_Py_CheckSlotResult(PyObject *obj, const char *slot_name, int success)

{

PyThreadState *tstate = _PyThreadState_GET();

if (!success) {

if (!_PyErr_Occurred(tstate)) {

_Py_FatalErrorFormat(__func__,

"Slot %s of type %s failed "

"without setting an exception",

slot_name, Py_TYPE(obj)->tp_name);

}

}

else {

if (_PyErr_Occurred(tstate)) {

_Py_FatalErrorFormat(__func__,

"Slot %s of type %s succeeded "

"with an exception set",

slot_name, Py_TYPE(obj)->tp_name);

}

}

return 1;

}

/* --- Core PyObject call functions ------------------------------- */

/* Call a callable Python object without any arguments */

PyObject *

PyObject_CallNoArgs(PyObject *func)

{

PyThreadState *tstate = _PyThreadState_GET();

return _PyObject_CallNoArgsTstate(tstate, func);

}

PyObject *

_PyObject_FastCallDictTstate(PyThreadState *tstate, PyObject *callable,

PyObject *const *args, size_t nargsf,

PyObject *kwargs)

{

assert(callable != NULL);

/* PyObject_VectorcallDict() must not be called with an exception set,

because it can clear it (directly or indirectly) and so the

caller loses its exception */

assert(!_PyErr_Occurred(tstate));

Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);

assert(nargs >= 0);

assert(nargs == 0 || args != NULL);

assert(kwargs == NULL || PyDict_Check(kwargs));

vectorcallfunc func = PyVectorcall_Function(callable);

if (func == NULL) {

/* Use tp_call instead */

return _PyObject_MakeTpCall(tstate, callable, args, nargs, kwargs);

}

PyObject *res;

if (kwargs == NULL || PyDict_GET_SIZE(kwargs) == 0) {

res = func(callable, args, nargsf, NULL);

}

else {

PyObject *kwnames;

PyObject *const *newargs;

newargs = _PyStack_UnpackDict(tstate,

args, nargs,

kwargs, &kwnames);

if (newargs == NULL) {

return NULL;

}

res = func(callable, newargs,

nargs | PY_VECTORCALL_ARGUMENTS_OFFSET, kwnames);

_PyStack_UnpackDict_Free(newargs, nargs, kwnames);

}

return _Py_CheckFunctionResult(tstate, callable, res, NULL);

}

PyObject *

PyObject_VectorcallDict(PyObject *callable, PyObject *const *args,

size_t nargsf, PyObject *kwargs)

{

PyThreadState *tstate = _PyThreadState_GET();

return _PyObject_FastCallDictTstate(tstate, callable, args, nargsf, kwargs);

}

PyObject *

_PyObject_MakeTpCall(PyThreadState *tstate, PyObject *callable,

PyObject *const *args, Py_ssize_t nargs,

PyObject *keywords)

{

assert(nargs >= 0);

assert(nargs == 0 || args != NULL);

assert(keywords == NULL || PyTuple_Check(keywords) || PyDict_Check(keywords));

/* Slow path: build a temporary tuple for positional arguments and a

* temporary dictionary for keyword arguments (if any) */

ternaryfunc call = Py_TYPE(callable)->tp_call;

if (call == NULL) {

_PyErr_Format(tstate, PyExc_TypeError,

"'%.200s' object is not callable",

Py_TYPE(callable)->tp_name);

return NULL;

}

PyObject *argstuple = _PyTuple_FromArray(args, nargs);

if (argstuple == NULL) {

return NULL;

}

PyObject *kwdict;

if (keywords == NULL || PyDict_Check(keywords)) {

kwdict = keywords;

}

else {

if (PyTuple_GET_SIZE(keywords)) {

assert(args != NULL);

kwdict = _PyStack_AsDict(args + nargs, keywords);

if (kwdict == NULL) {

Py_DECREF(argstuple);

return NULL;

}

}

else {

keywords = kwdict = NULL;

}

}

PyObject *result = NULL;

if (_Py_EnterRecursiveCall(tstate, " while calling a Python object") == 0)

{

result = call(callable, argstuple, kwdict);

_Py_LeaveRecursiveCall(tstate);

}

Py_DECREF(argstuple);

if (kwdict != keywords) {

Py_DECREF(kwdict);

}

return _Py_CheckFunctionResult(tstate, callable, result, NULL);

}

static PyObject *

_PyVectorcall_Call(PyThreadState *tstate, vectorcallfunc func,

PyObject *callable, PyObject *tuple, PyObject *kwargs)

{

assert(func != NULL);

Py_ssize_t nargs = PyTuple_GET_SIZE(tuple);

/* Fast path for no keywords */

if (kwargs == NULL || PyDict_GET_SIZE(kwargs) == 0) {

return func(callable, _PyTuple_ITEMS(tuple), nargs, NULL);

}

/* Convert arguments & call */

PyObject *const *args;

PyObject *kwnames;

args = _PyStack_UnpackDict(tstate,

_PyTuple_ITEMS(tuple), nargs,

kwargs, &kwnames);

if (args == NULL) {

return NULL;

}

PyObject *result = func(callable, args,

nargs | PY_VECTORCALL_ARGUMENTS_OFFSET, kwnames);

_PyStack_UnpackDict_Free(args, nargs, kwnames);

return _Py_CheckFunctionResult(tstate, callable, result, NULL);

}

PyObject *

PyVectorcall_Call(PyObject *callable, PyObject *tuple, PyObject *kwargs)

{

PyThreadState *tstate = _PyThreadState_GET();

/* get vectorcallfunc as in PyVectorcall_Function, but without

* the Py_TPFLAGS_HAVE_VECTORCALL check */

Py_ssize_t offset = Py_TYPE(callable)->tp_vectorcall_offset;

if (offset <= 0) {

_PyErr_Format(tstate, PyExc_TypeError,

"'%.200s' object does not support vectorcall",

Py_TYPE(callable)->tp_name);

return NULL;

}

assert(PyCallable_Check(callable));

vectorcallfunc func;

memcpy(&func, (char *) callable + offset, sizeof(func));

if (func == NULL) {

_PyErr_Format(tstate, PyExc_TypeError,

"'%.200s' object does not support vectorcall",

Py_TYPE(callable)->tp_name);

return NULL;

}

return _PyVectorcall_Call(tstate, func, callable, tuple, kwargs);

}

PyObject *

_PyObject_Call(PyThreadState *tstate, PyObject *callable,

PyObject *args, PyObject *kwargs)

{

ternaryfunc call;

PyObject *result;

/* PyObject_Call() must not be called with an exception set,

because it can clear it (directly or indirectly) and so the

caller loses its exception */

assert(!_PyErr_Occurred(tstate));

assert(PyTuple_Check(args));

assert(kwargs == NULL || PyDict_Check(kwargs));

vectorcallfunc vector_func = PyVectorcall_Function(callable);

if (vector_func != NULL) {

return _PyVectorcall_Call(tstate, vector_func, callable, args, kwargs);

}

else {

call = Py_TYPE(callable)->tp_call;

if (call == NULL) {

_PyErr_Format(tstate, PyExc_TypeError,

"'%.200s' object is not callable",

Py_TYPE(callable)->tp_name);

return NULL;

}

if (_Py_EnterRecursiveCall(tstate, " while calling a Python object")) {

return NULL;

}

result = (*call)(callable, args, kwargs);

_Py_LeaveRecursiveCall(tstate);

return _Py_CheckFunctionResult(tstate, callable, result, NULL);

}

}

PyObject *

PyObject_Call(PyObject *callable, PyObject *args, PyObject *kwargs)

{

PyThreadState *tstate = _PyThreadState_GET();

return _PyObject_Call(tstate, callable, args, kwargs);

}

PyObject *

PyCFunction_Call(PyObject *callable, PyObject *args, PyObject *kwargs)

{

PyThreadState *tstate = _PyThreadState_GET();

return _PyObject_Call(tstate, callable, args, kwargs);

}

/* --- PyFunction call functions ---------------------------------- */

PyObject *

_PyFunction_Vectorcall(PyObject *func, PyObject* const* stack,

size_t nargsf, PyObject *kwnames)

{

assert(PyFunction_Check(func));

PyFrameConstructor *f = PyFunction_AS_FRAME_CONSTRUCTOR(func);

Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);

assert(nargs >= 0);

PyThreadState *tstate = _PyThreadState_GET();

assert(nargs == 0 || stack != NULL);

if (((PyCodeObject *)f->fc_code)->co_flags & CO_OPTIMIZED) {

return _PyEval_Vector(tstate, f, NULL, stack, nargs, kwnames);

}

else {

return _PyEval_Vector(tstate, f, f->fc_globals, stack, nargs, kwnames);

}

}

/* --- More complex call functions -------------------------------- */

/* External interface to call any callable object.

The args must be a tuple or NULL. The kwargs must be a dict or NULL. */

PyObject *

PyEval_CallObjectWithKeywords(PyObject *callable,

PyObject *args, PyObject *kwargs)

{

PyThreadState *tstate = _PyThreadState_GET();

#ifdef Py_DEBUG

/* PyEval_CallObjectWithKeywords() must not be called with an exception

set. It raises a new exception if parameters are invalid or if

PyTuple_New() fails, and so the original exception is lost. */

assert(!_PyErr_Occurred(tstate));

#endif

if (args != NULL && !PyTuple_Check(args)) {

_PyErr_SetString(tstate, PyExc_TypeError,

"argument list must be a tuple");

return NULL;

}

if (kwargs != NULL && !PyDict_Check(kwargs)) {

_PyErr_SetString(tstate, PyExc_TypeError,

"keyword list must be a dictionary");

return NULL;

}

if (args == NULL) {

return _PyObject_FastCallDictTstate(tstate, callable, NULL, 0, kwargs);

}

else {

return _PyObject_Call(tstate, callable, args, kwargs);

}

}

PyObject *

PyObject_CallObject(PyObject *callable, PyObject *args)

{

PyThreadState *tstate = _PyThreadState_GET();

assert(!_PyErr_Occurred(tstate));

if (args == NULL) {

return _PyObject_CallNoArgsTstate(tstate, callable);

}

if (!PyTuple_Check(args)) {

_PyErr_SetString(tstate, PyExc_TypeError,

"argument list must be a tuple");

return NULL;

}

return _PyObject_Call(tstate, callable, args, NULL);

}

/* Call callable(obj, *args, **kwargs). */

PyObject *

_PyObject_Call_Prepend(PyThreadState *tstate, PyObject *callable,

PyObject *obj, PyObject *args, PyObject *kwargs)

{

assert(PyTuple_Check(args));

PyObject *small_stack[_PY_FASTCALL_SMALL_STACK];

PyObject **stack;

Py_ssize_t argcount = PyTuple_GET_SIZE(args);

if (argcount + 1 <= (Py_ssize_t)Py_ARRAY_LENGTH(small_stack)) {

stack = small_stack;

}

else {

stack = PyMem_Malloc((argcount + 1) * sizeof(PyObject *));

if (stack == NULL) {

PyErr_NoMemory();

return NULL;

}

}

/* use borrowed references */

stack[0] = obj;

memcpy(&stack[1],

_PyTuple_ITEMS(args),

argcount * sizeof(PyObject *));

PyObject *result = _PyObject_FastCallDictTstate(tstate, callable,

stack, argcount + 1,

kwargs);

if (stack != small_stack) {

PyMem_Free(stack);

}

return result;

}

/* --- Call with a format string ---------------------------------- */

static PyObject *

_PyObject_CallFunctionVa(PyThreadState *tstate, PyObject *callable,

const char *format, va_list va, int is_size_t)

{

PyObject* small_stack[_PY_FASTCALL_SMALL_STACK];

const Py_ssize_t small_stack_len = Py_ARRAY_LENGTH(small_stack);

PyObject **stack;

Py_ssize_t nargs, i;

PyObject *result;

if (callable == NULL) {

return null_error(tstate);

}

if (!format || !*format) {

return _PyObject_CallNoArgsTstate(tstate, callable);

}

if (is_size_t) {

stack = _Py_VaBuildStack_SizeT(small_stack, small_stack_len,

format, va, &nargs);

}

else {

stack = _Py_VaBuildStack(small_stack, small_stack_len,

format, va, &nargs);

}

if (stack == NULL) {

return NULL;

}

if (nargs == 1 && PyTuple_Check(stack[0])) {

/* Special cases for backward compatibility:

- PyObject_CallFunction(func, "O", tuple) calls func(*tuple)

- PyObject_CallFunction(func, "(OOO)", arg1, arg2, arg3) calls

func(*(arg1, arg2, arg3)): func(arg1, arg2, arg3) */

PyObject *args = stack[0];

result = _PyObject_VectorcallTstate(tstate, callable,

_PyTuple_ITEMS(args),

PyTuple_GET_SIZE(args),

NULL);

}

else {

result = _PyObject_VectorcallTstate(tstate, callable,

stack, nargs, NULL);

}

for (i = 0; i < nargs; ++i) {

Py_DECREF(stack[i]);

}

if (stack != small_stack) {

PyMem_Free(stack);

}

return result;

}

PyObject *

PyObject_CallFunction(PyObject *callable, const char *format, ...)

{

va_list va;

PyObject *result;

PyThreadState *tstate = _PyThreadState_GET();

va_start(va, format);

result = _PyObject_CallFunctionVa(tstate, callable, format, va, 0);

va_end(va);

return result;

}

/* PyEval_CallFunction is exact copy of PyObject_CallFunction.

* This function is kept for backward compatibility.

*/

PyObject *

PyEval_CallFunction(PyObject *callable, const char *format, ...)

{

va_list va;

PyObject *result;

PyThreadState *tstate = _PyThreadState_GET();

va_start(va, format);

result = _PyObject_CallFunctionVa(tstate, callable, format, va, 0);

va_end(va);

return result;

}

PyObject *

_PyObject_CallFunction_SizeT(PyObject *callable, const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

va_list va;

va_start(va, format);

PyObject *result = _PyObject_CallFunctionVa(tstate, callable, format, va, 1);

va_end(va);

return result;

}

static PyObject*

callmethod(PyThreadState *tstate, PyObject* callable, const char *format, va_list va, int is_size_t)

{

assert(callable != NULL);

if (!PyCallable_Check(callable)) {

_PyErr_Format(tstate, PyExc_TypeError,

"attribute of type '%.200s' is not callable",

Py_TYPE(callable)->tp_name);

return NULL;

}

return _PyObject_CallFunctionVa(tstate, callable, format, va, is_size_t);

}

PyObject *

PyObject_CallMethod(PyObject *obj, const char *name, const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = PyObject_GetAttrString(obj, name);

if (callable == NULL) {

return NULL;

}

va_list va;

va_start(va, format);

PyObject *retval = callmethod(tstate, callable, format, va, 0);

va_end(va);

Py_DECREF(callable);

return retval;

}

/* PyEval_CallMethod is exact copy of PyObject_CallMethod.

* This function is kept for backward compatibility.

*/

PyObject *

PyEval_CallMethod(PyObject *obj, const char *name, const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = PyObject_GetAttrString(obj, name);

if (callable == NULL) {

return NULL;

}

va_list va;

va_start(va, format);

PyObject *retval = callmethod(tstate, callable, format, va, 0);

va_end(va);

Py_DECREF(callable);

return retval;

}

PyObject *

_PyObject_CallMethodId(PyObject *obj, _Py_Identifier *name,

const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = _PyObject_GetAttrId(obj, name);

if (callable == NULL) {

return NULL;

}

va_list va;

va_start(va, format);

PyObject *retval = callmethod(tstate, callable, format, va, 0);

va_end(va);

Py_DECREF(callable);

return retval;

}

PyObject *

_PyObject_CallMethod_SizeT(PyObject *obj, const char *name,

const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = PyObject_GetAttrString(obj, name);

if (callable == NULL) {

return NULL;

}

va_list va;

va_start(va, format);

PyObject *retval = callmethod(tstate, callable, format, va, 1);

va_end(va);

Py_DECREF(callable);

return retval;

}

PyObject *

_PyObject_CallMethodId_SizeT(PyObject *obj, _Py_Identifier *name,

const char *format, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = _PyObject_GetAttrId(obj, name);

if (callable == NULL) {

return NULL;

}

va_list va;

va_start(va, format);

PyObject *retval = callmethod(tstate, callable, format, va, 1);

va_end(va);

Py_DECREF(callable);

return retval;

}

/* --- Call with "..." arguments ---------------------------------- */

static PyObject *

object_vacall(PyThreadState *tstate, PyObject *base,

PyObject *callable, va_list vargs)

{

PyObject *small_stack[_PY_FASTCALL_SMALL_STACK];

PyObject **stack;

Py_ssize_t nargs;

PyObject *result;

Py_ssize_t i;

va_list countva;

if (callable == NULL) {

return null_error(tstate);

}

/* Count the number of arguments */

va_copy(countva, vargs);

nargs = base ? 1 : 0;

while (1) {

PyObject *arg = va_arg(countva, PyObject *);

if (arg == NULL) {

break;

}

nargs++;

}

va_end(countva);

/* Copy arguments */

if (nargs <= (Py_ssize_t)Py_ARRAY_LENGTH(small_stack)) {

stack = small_stack;

}

else {

stack = PyMem_Malloc(nargs * sizeof(stack[0]));

if (stack == NULL) {

PyErr_NoMemory();

return NULL;

}

}

i = 0;

if (base) {

stack[i++] = base;

}

for (; i < nargs; ++i) {

stack[i] = va_arg(vargs, PyObject *);

}

/* Call the function */

result = _PyObject_VectorcallTstate(tstate, callable, stack, nargs, NULL);

if (stack != small_stack) {

PyMem_Free(stack);

}

return result;

}

PyObject *

PyObject_VectorcallMethod(PyObject *name, PyObject *const *args,

size_t nargsf, PyObject *kwnames)

{

assert(name != NULL);

assert(args != NULL);

assert(PyVectorcall_NARGS(nargsf) >= 1);

PyThreadState *tstate = _PyThreadState_GET();

PyObject *callable = NULL;

/* Use args[0] as "self" argument */

int unbound = _PyObject_GetMethod(args[0], name, &callable);

if (callable == NULL) {

return NULL;

}

if (unbound) {

/* We must remove PY_VECTORCALL_ARGUMENTS_OFFSET since

* that would be interpreted as allowing to change args[-1] */

nargsf &= ~PY_VECTORCALL_ARGUMENTS_OFFSET;

}

else {

/* Skip "self". We can keep PY_VECTORCALL_ARGUMENTS_OFFSET since

* args[-1] in the onward call is args[0] here. */

args++;

nargsf--;

}

PyObject *result = _PyObject_VectorcallTstate(tstate, callable,

args, nargsf, kwnames);

Py_DECREF(callable);

return result;

}

PyObject *

PyObject_CallMethodObjArgs(PyObject *obj, PyObject *name, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *callable = NULL;

int is_method = _PyObject_GetMethod(obj, name, &callable);

if (callable == NULL) {

return NULL;

}

obj = is_method ? obj : NULL;

va_list vargs;

va_start(vargs, name);

PyObject *result = object_vacall(tstate, obj, callable, vargs);

va_end(vargs);

Py_DECREF(callable);

return result;

}

PyObject *

_PyObject_CallMethodIdObjArgs(PyObject *obj,

struct _Py_Identifier *name, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

if (obj == NULL || name == NULL) {

return null_error(tstate);

}

PyObject *oname = _PyUnicode_FromId(name); /* borrowed */

if (!oname) {

return NULL;

}

PyObject *callable = NULL;

int is_method = _PyObject_GetMethod(obj, oname, &callable);

if (callable == NULL) {

return NULL;

}

obj = is_method ? obj : NULL;

va_list vargs;

va_start(vargs, name);

PyObject *result = object_vacall(tstate, obj, callable, vargs);

va_end(vargs);

Py_DECREF(callable);

return result;

}

PyObject *

PyObject_CallFunctionObjArgs(PyObject *callable, ...)

{

PyThreadState *tstate = _PyThreadState_GET();

va_list vargs;

PyObject *result;

va_start(vargs, callable);

result = object_vacall(tstate, NULL, callable, vargs);

va_end(vargs);

return result;

}

/* --- PyStack functions ------------------------------------------ */

PyObject *

_PyStack_AsDict(PyObject *const *values, PyObject *kwnames)

{

Py_ssize_t nkwargs;

PyObject *kwdict;

Py_ssize_t i;

assert(kwnames != NULL);

nkwargs = PyTuple_GET_SIZE(kwnames);

kwdict = _PyDict_NewPresized(nkwargs);

if (kwdict == NULL) {

return NULL;

}

for (i = 0; i < nkwargs; i++) {

PyObject *key = PyTuple_GET_ITEM(kwnames, i);

PyObject *value = *values++;

/* If key already exists, replace it with the new value */

if (PyDict_SetItem(kwdict, key, value)) {

Py_DECREF(kwdict);

return NULL;

}

}

return kwdict;

}

/* Convert (args, nargs, kwargs: dict) into a (stack, nargs, kwnames: tuple).

Allocate a new argument vector and keyword names tuple. Return the argument

vector; return NULL with exception set on error. Return the keyword names

tuple in *p_kwnames.

This also checks that all keyword names are strings. If not, a TypeError is

raised.

The newly allocated argument vector supports PY_VECTORCALL_ARGUMENTS_OFFSET.

When done, you must call _PyStack_UnpackDict_Free(stack, nargs, kwnames) */

static PyObject *const *

_PyStack_UnpackDict(PyThreadState *tstate,

PyObject *const *args, Py_ssize_t nargs,

PyObject *kwargs, PyObject **p_kwnames)

{

assert(nargs >= 0);

assert(kwargs != NULL);

assert(PyDict_Check(kwargs));

Py_ssize_t nkwargs = PyDict_GET_SIZE(kwargs);

/* Check for overflow in the PyMem_Malloc() call below. The subtraction

* in this check cannot overflow: both maxnargs and nkwargs are

* non-negative signed integers, so their difference fits in the type. */

Py_ssize_t maxnargs = PY_SSIZE_T_MAX / sizeof(args[0]) - 1;

if (nargs > maxnargs - nkwargs) {

_PyErr_NoMemory(tstate);

return NULL;

}

/* Add 1 to support PY_VECTORCALL_ARGUMENTS_OFFSET */

PyObject **stack = PyMem_Malloc((1 + nargs + nkwargs) * sizeof(args[0]));

if (stack == NULL) {

_PyErr_NoMemory(tstate);

return NULL;

}

PyObject *kwnames = PyTuple_New(nkwargs);

if (kwnames == NULL) {

PyMem_Free(stack);

return NULL;

}

stack++; /* For PY_VECTORCALL_ARGUMENTS_OFFSET */

/* Copy positional arguments */

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

Py_INCREF(args[i]);

stack[i] = args[i];

}

PyObject **kwstack = stack + nargs;

/* This loop doesn't support lookup function mutating the dictionary

to change its size. It's a deliberate choice for speed, this function is

called in the performance critical hot code. */

Py_ssize_t pos = 0, i = 0;

PyObject *key, *value;

unsigned long keys_are_strings = Py_TPFLAGS_UNICODE_SUBCLASS;

while (PyDict_Next(kwargs, &pos, &key, &value)) {

keys_are_strings &= Py_TYPE(key)->tp_flags;

Py_INCREF(key);

Py_INCREF(value);

PyTuple_SET_ITEM(kwnames, i, key);

kwstack[i] = value;

i++;

}

/* keys_are_strings has the value Py_TPFLAGS_UNICODE_SUBCLASS if that

* flag is set for all keys. Otherwise, keys_are_strings equals 0.

* We do this check once at the end instead of inside the loop above

* because it simplifies the deallocation in the failing case.

* It happens to also make the loop above slightly more efficient. */

if (!keys_are_strings) {

_PyErr_SetString(tstate, PyExc_TypeError,

"keywords must be strings");

_PyStack_UnpackDict_Free(stack, nargs, kwnames);

return NULL;

}

*p_kwnames = kwnames;

return stack;

}

static void

_PyStack_UnpackDict_Free(PyObject *const *stack, Py_ssize_t nargs,

PyObject *kwnames)

{

Py_ssize_t n = PyTuple_GET_SIZE(kwnames) + nargs;

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

Py_DECREF(stack[i]);

}

PyMem_Free((PyObject **)stack - 1);

Py_DECREF(kwnames);

}