gh-132639: Adds PyLong_AsNativeBytes, PyLong_FromNativeBytes and PyLong_FromUnsignedNativeBytes to the limited API (GH-132640)

Author: zooba

Doc/data/stable_abi.dat

@@ -7,57 +7,6 @@
 
 PyAPI_FUNC(PyObject*) PyLong_FromUnicodeObject(PyObject *u, int base);
 
-#define Py_ASNATIVEBYTES_DEFAULTS -1
-#define Py_ASNATIVEBYTES_BIG_ENDIAN 0
-#define Py_ASNATIVEBYTES_LITTLE_ENDIAN 1
-#define Py_ASNATIVEBYTES_NATIVE_ENDIAN 3
-#define Py_ASNATIVEBYTES_UNSIGNED_BUFFER 4
-#define Py_ASNATIVEBYTES_REJECT_NEGATIVE 8
-#define Py_ASNATIVEBYTES_ALLOW_INDEX 16
-
-/* PyLong_AsNativeBytes: Copy the integer value to a native variable.
-   buffer points to the first byte of the variable.
-   n_bytes is the number of bytes available in the buffer. Pass 0 to request
-   the required size for the value.
-   flags is a bitfield of the following flags:
-   * 1 - little endian
-   * 2 - native endian
-   * 4 - unsigned destination (e.g. don't reject copying 255 into one byte)
-   * 8 - raise an exception for negative inputs
-   * 16 - call __index__ on non-int types
-   If flags is -1 (all bits set), native endian is used, value truncation
-   behaves most like C (allows negative inputs and allow MSB set), and non-int
-   objects will raise a TypeError.
-   Big endian mode will write the most significant byte into the address
-   directly referenced by buffer; little endian will write the least significant
-   byte into that address.
-
-   If an exception is raised, returns a negative value.
-   Otherwise, returns the number of bytes that are required to store the value.
-   To check that the full value is represented, ensure that the return value is
-   equal or less than n_bytes.
-   All n_bytes are guaranteed to be written (unless an exception occurs), and
-   so ignoring a positive return value is the equivalent of a downcast in C.
-   In cases where the full value could not be represented, the returned value
-   may be larger than necessary - this function is not an accurate way to
-   calculate the bit length of an integer object.
-   */
-PyAPI_FUNC(Py_ssize_t) PyLong_AsNativeBytes(PyObject* v, void* buffer,
-    Py_ssize_t n_bytes, int flags);
-
-/* PyLong_FromNativeBytes: Create an int value from a native integer
-   n_bytes is the number of bytes to read from the buffer. Passing 0 will
-   always produce the zero int.
-   PyLong_FromUnsignedNativeBytes always produces a non-negative int.
-   flags is the same as for PyLong_AsNativeBytes, but only supports selecting
-   the endianness or forcing an unsigned buffer.
-
-   Returns the int object, or NULL with an exception set. */
-PyAPI_FUNC(PyObject*) PyLong_FromNativeBytes(const void* buffer, size_t n_bytes,
-    int flags);
-PyAPI_FUNC(PyObject*) PyLong_FromUnsignedNativeBytes(const void* buffer,
-    size_t n_bytes, int flags);
-
 PyAPI_FUNC(int) PyUnstable_Long_IsCompact(const PyLongObject* op);
 PyAPI_FUNC(Py_ssize_t) PyUnstable_Long_CompactValue(const PyLongObject* op);
 

Include/cpython/longobject.h

@@ -40,6 +40,58 @@ PyAPI_FUNC(int) PyLong_AsInt32(PyObject *obj, int32_t *value);
 PyAPI_FUNC(int) PyLong_AsUInt32(PyObject *obj, uint32_t *value);
 PyAPI_FUNC(int) PyLong_AsInt64(PyObject *obj, int64_t *value);
 PyAPI_FUNC(int) PyLong_AsUInt64(PyObject *obj, uint64_t *value);
+
+#define Py_ASNATIVEBYTES_DEFAULTS -1
+#define Py_ASNATIVEBYTES_BIG_ENDIAN 0
+#define Py_ASNATIVEBYTES_LITTLE_ENDIAN 1
+#define Py_ASNATIVEBYTES_NATIVE_ENDIAN 3
+#define Py_ASNATIVEBYTES_UNSIGNED_BUFFER 4
+#define Py_ASNATIVEBYTES_REJECT_NEGATIVE 8
+#define Py_ASNATIVEBYTES_ALLOW_INDEX 16
+
+/* PyLong_AsNativeBytes: Copy the integer value to a native variable.
+   buffer points to the first byte of the variable.
+   n_bytes is the number of bytes available in the buffer. Pass 0 to request
+   the required size for the value.
+   flags is a bitfield of the following flags:
+   * 1 - little endian
+   * 2 - native endian
+   * 4 - unsigned destination (e.g. don't reject copying 255 into one byte)
+   * 8 - raise an exception for negative inputs
+   * 16 - call __index__ on non-int types
+   If flags is -1 (all bits set), native endian is used, value truncation
+   behaves most like C (allows negative inputs and allow MSB set), and non-int
+   objects will raise a TypeError.
+   Big endian mode will write the most significant byte into the address
+   directly referenced by buffer; little endian will write the least significant
+   byte into that address.
+
+   If an exception is raised, returns a negative value.
+   Otherwise, returns the number of bytes that are required to store the value.
+   To check that the full value is represented, ensure that the return value is
+   equal or less than n_bytes.
+   All n_bytes are guaranteed to be written (unless an exception occurs), and
+   so ignoring a positive return value is the equivalent of a downcast in C.
+   In cases where the full value could not be represented, the returned value
+   may be larger than necessary - this function is not an accurate way to
+   calculate the bit length of an integer object.
+   */
+PyAPI_FUNC(Py_ssize_t) PyLong_AsNativeBytes(PyObject* v, void* buffer,
+    Py_ssize_t n_bytes, int flags);
+
+/* PyLong_FromNativeBytes: Create an int value from a native integer
+   n_bytes is the number of bytes to read from the buffer. Passing 0 will
+   always produce the zero int.
+   PyLong_FromUnsignedNativeBytes always produces a non-negative int.
+   flags is the same as for PyLong_AsNativeBytes, but only supports selecting
+   the endianness or forcing an unsigned buffer.
+
+   Returns the int object, or NULL with an exception set. */
+PyAPI_FUNC(PyObject*) PyLong_FromNativeBytes(const void* buffer, size_t n_bytes,
+    int flags);
+PyAPI_FUNC(PyObject*) PyLong_FromUnsignedNativeBytes(const void* buffer,
+    size_t n_bytes, int flags);
+
 #endif
 
 PyAPI_FUNC(PyObject *) PyLong_GetInfo(void);

Include/longobject.h

@@ -0,0 +1,2 @@
+Added :c:func:`PyLong_AsNativeBytes`, :c:func:`PyLong_FromNativeBytes` and
+:c:func:`PyLong_FromUnsignedNativeBytes` to the limited C API.

Lib/test/test_stable_abi_ctypes.py

@@ -2528,6 +2528,26 @@
     added = '3.14'
 [function.PyLong_AsUInt64]
     added = '3.14'
+[function.PyLong_AsNativeBytes]
+    added = '3.14'
+[function.PyLong_FromNativeBytes]
+    added = '3.14'
+[function.PyLong_FromUnsignedNativeBytes]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_DEFAULTS]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_BIG_ENDIAN]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_LITTLE_ENDIAN]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_NATIVE_ENDIAN]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_UNSIGNED_BUFFER]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_REJECT_NEGATIVE]
+    added = '3.14'
+[const.Py_ASNATIVEBYTES_ALLOW_INDEX]
+    added = '3.14'
 [const.Py_tp_vectorcall]
     added = '3.14'
 [function.PyType_GetBaseByToken]