Dec 13, 2024 · Jul 2, 2024 · Jul 23, 2024 · Sep 3, 2024 · Sep 3, 2024 · Sep 3, 2024
diff --git a/Doc/c-api/long.rst b/Doc/c-api/long.rst

 .. c:struct:: PyLongLayout

   Layout of an array of digits, used by Python :class:`int` object.
   Layout of an array of "digits" ("limbs" in the GMP terminology), used to
   represent absolute value for arbitrary precision integers.

   Use :c:func:`PyLong_GetNativeLayout` to get the native layout of Python
   :class:`int` objects.
   :class:`int` objects, used internally for integers with "big enough"
   absolute value.

   See also :data:`sys.int_info` which exposes similar information to Python.


   See the :c:struct:`PyLongLayout` structure.

   The function must not be called before Python initialization nor after
   Python finalization. The returned layout is valid until Python is
   finalized. The layout is the same for all Python sub-interpreters and
   so it can be cached.


 .. c:struct:: PyLongExport

   On success, set *\*export_long* and return 0.
   On error, set an exception and return -1.

   This function always succeeds if *obj* is a Python :class:`int` object or a
   subclass.

   If *export_long.digits* is not ``NULL``, :c:func:`PyLong_FreeExport` must be
   called when the export is no longer needed.


   A Python :class:`int` writer instance.

   The instance must be destroyed by :c:func:`PyLongWriter_Finish`.
   The instance must be destroyed by :c:func:`PyLongWriter_Finish` or
   :c:func:`PyLongWriter_Discard`.


 .. c:function:: PyLongWriter* PyLongWriter_Create(int negative, Py_ssize_t ndigits, void **digits)
   *ndigits* is the number of digits in the *digits* array. It must be
   greater than or equal to 0.

   The caller must initialize the array of digits *digits* and then call
   :c:func:`PyLongWriter_Finish` to get a Python :class:`int`. Digits must be
   in the range [``0``; ``PyLong_BASE - 1``]. Unused digits must be set to
   ``0``.
   The caller can either initialize the array of digits *digits* and then call
   :c:func:`PyLongWriter_Finish` to get a Python :class:`int`, or call
   :c:func:`PyLongWriter_Discard` to destroy the writer instance.  Digits must
   be in the range [``0``; ``(1 << sys.int_info.bits_per_digit) - 1``].  Unused
   digits must be set to ``0``.


 .. c:function:: PyObject* PyLongWriter_Finish(PyLongWriter *writer)

 .. c:function:: void PyLongWriter_Discard(PyLongWriter *writer)

   Discardthe internal object and destroy the writer instance.
   Discarda :c:type:`PyLongWriter` created by :c:func:`PyLongWriter_Create`.
diff --git a/Include/cpython/longintrepr.h b/Include/cpython/longintrepr.h
    // Digit size in bytes
    uint8_t digit_size;

    //Word endian:
    // * 1 for most significantword first (big endian)
    // * -1 for least significant first (little endian)
    //Digits order:
    // * 1 for most significantdigit first
    // * -1 for least significant first
    int8_t digits_order;

    //Array endian:
    //Digit endianness:
    // * 1 for most significant byte first (big endian)
    // * -1 for least significant first (little endian)
    int8_tendian;
    int8_tendianness;
 } PyLongLayout;

 PyAPI_FUNC(const PyLongLayout*) PyLong_GetNativeLayout(void);
diff --git a/Lib/test/test_capi/test_long.py b/Lib/test/test_capi/test_long.py
            'bits_per_digit': int_info.bits_per_digit,
            'digit_size': int_info.sizeof_digit,
            'digits_order': -1,
            'endian': -1 if sys.byteorder == 'little' else 1,
            'endianness': -1 if sys.byteorder == 'little' else 1,
        }
        self.assertEqual(layout, expected)

diff --git a/Modules/_testcapi/long.c b/Modules/_testcapi/long.c
        goto error;
    }

    value = PyLong_FromLong(layout->endian);
    value = PyLong_FromLong(layout->endianness);
    if (value == NULL) {
        goto error;
    }
    res = PyDict_SetItemString(dict, "endian", value);
    res = PyDict_SetItemString(dict, "endianness", value);
    Py_DECREF(value);
    if (res < 0) {
        goto error;
diff --git a/Objects/longobject.c b/Objects/longobject.c
 static const PyLongLayout PyLong_LAYOUT = {
    .bits_per_digit = PyLong_SHIFT,
    .digits_order = -1,  // least significant first
    .endian = PY_LITTLE_ENDIAN ? -1 : 1,
    .endianness = PY_LITTLE_ENDIAN ? -1 : 1,
    .digit_size = sizeof(digit),
 };
Original file line number	Diff line number	Diff line change
Expand Up		@@ -148,15 +148,15 @@ typedef struct PyLongLayout {
		// Digit size in bytes
		uint8_t digit_size;

		//Word endian:
		// * 1 for most significantword first (big endian)
		// * -1 for least significant first (little endian)
		//Digits order:
		// * 1 for most significantdigit first
		// * -1 for least significant first
		int8_t digits_order;

		//Array endian:
		//Digit endianness:
		// * 1 for most significant byte first (big endian)
		// * -1 for least significant first (little endian)
		int8_tendian;
		int8_tendianness;
		} PyLongLayout;

		PyAPI_FUNC(const PyLongLayout*) PyLong_GetNativeLayout(void);
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Original file line number	Diff line number	Diff line change
Expand Up		@@ -678,7 +678,7 @@ def test_long_layout(self):
		'bits_per_digit': int_info.bits_per_digit,
		'digit_size': int_info.sizeof_digit,
		'digits_order': -1,
		'endian': -1 if sys.byteorder == 'little' else 1,
		'endianness': -1 if sys.byteorder == 'little' else 1,
		}
		self.assertEqual(layout, expected)

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Original file line number	Diff line number	Diff line change
Expand Up		@@ -155,11 +155,11 @@ layout_to_dict(const PyLongLayout *layout)
		goto error;
		}

		value = PyLong_FromLong(layout->endian);
		value = PyLong_FromLong(layout->endianness);
		if (value == NULL) {
		goto error;
		}
		res = PyDict_SetItemString(dict, "endian", value);
		res = PyDict_SetItemString(dict, "endianness", value);
		Py_DECREF(value);
		if (res < 0) {
		goto error;
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -6779,7 +6779,7 @@ int PyLong_AsUInt64(PyObject obj, uint64_t value)
		static const PyLongLayout PyLong_LAYOUT = {
		.bits_per_digit = PyLong_SHIFT,
		.digits_order = -1, // least significant first
		.endian = PY_LITTLE_ENDIAN ? -1 : 1,
		.endianness = PY_LITTLE_ENDIAN ? -1 : 1,
		.digit_size = sizeof(digit),
		};

Expand Down