cpython/Include
Pieter Eendebak 7e38e6745d
gh-123271: Make builtin zip method safe under free-threading (#123272)
The `zip_next` function uses a common optimization technique for methods
that generate tuples. The iterator maintains an internal reference to
the returned tuple. When the method is called again, it checks if the
internal tuple's reference count is 1. If so, the tuple can be reused.
However, this approach is not safe under the free-threading build:
after checking the reference count, another thread may perform the same
check and also reuse the tuple. This can result in a double decref on
the items of the replaced tuple and a double incref (memory leak) on
the items of the tuple being set.

This adds a function, `_PyObject_IsUniquelyReferenced` that
encapsulates the stricter logic necessary for the free-threaded build:
the internal tuple must be owned by the current thread, have a local
refcount of one, and a shared refcount of zero.
2024-08-27 15:22:43 -04:00
..
cpython gh-122417: Implement per-thread heap type refcounts (#122418) 2024-08-06 14:36:57 -04:00
internal gh-123271: Make builtin zip method safe under free-threading (#123272) 2024-08-27 15:22:43 -04:00
abstract.h gh-105201: Add PyIter_NextItem() (#122331) 2024-08-08 00:47:15 +02:00
bltinmodule.h these builtins have to be initialized 2009-05-09 18:10:51 +00:00
boolobject.h gh-115754: Add Py_GetConstant() function (#116883) 2024-03-21 16:07:00 +00:00
bytearrayobject.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
bytesobject.h gh-108765: Move standard includes to Python.h (#108769) 2023-09-01 21:03:20 +02:00
ceval.h GH-120507: Lower the BEFORE_WITH and BEFORE_ASYNC_WITH instructions. (#120640) 2024-06-18 12:17:46 +01:00
codecs.h Remove private _PyCodec_Lookup() function (#106269) 2023-06-30 09:34:01 +00:00
compile.h gh-109596: Ensure repeated rules in the grammar are not allowed and fix incorrect soft keywords (#109606) 2023-09-22 19:03:23 +01:00
complexobject.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
critical_section.h gh-119344: Make critical section API public (#119353) 2024-06-21 15:50:18 -04:00
datetime.h gh-87347: Add parenthesis around macro arguments (#93915) 2022-06-20 16:04:52 +02:00
descrobject.h gh-103509: PEP 697 -- Limited C API for Extending Opaque Types (GH-103511) 2023-05-04 09:56:53 +02:00
dictobject.h gh-106004: PyDict_GetItemRef() should only be in the limited API 3.13 (GH-107229) 2023-07-25 21:48:07 +03:00
dynamic_annotations.h gh-96959: Update HTTP links which are redirected to HTTPS (GH-96961) 2022-09-24 14:38:53 +03:00
enumobject.h Implement and apply PEP 322, reverse iteration 2003-11-06 14:06:48 +00:00
errcode.h gh-107450: Check for overflow in the tokenizer and fix overflow test (#110832) 2023-10-16 16:42:49 +02:00
exports.h gh-121040: Use __attribute__((fallthrough)) (#121044) 2024-06-27 09:58:44 +00:00
fileobject.h gh-106320: Remove _PyIsSelectable_fd() C API (#107142) 2023-07-23 19:07:12 +00:00
fileutils.h gh-108765: Move stat() fiddling from pyport.h to fileutils.h (#108854) 2023-09-03 21:32:13 +00:00
floatobject.h gh-121905: Consistently use "floating-point" instead of "floating point" (GH-121907) 2024-07-19 08:06:02 +00:00
frameobject.h bpo-45434: Remove useless space in includes (GH-28963) 2021-10-15 01:50:04 +02:00
genericaliasobject.h bpo-44654: Refactor and clean up the union type implementation (GH-27196) 2021-07-17 22:44:10 +03:00
import.h gh-105922: Add PyImport_AddModuleRef() function (#105923) 2023-06-20 08:48:14 +02:00
intrcheck.h gh-106320: Remove private _PyOS_IsMainThread() function (#108605) 2023-08-29 03:20:31 +00:00
iterobject.h gh-106320: Remove _PyAnextAwaitable_Type from the public C API (#108597) 2023-08-29 02:05:11 +00:00
listobject.h gh-114329: Fix PyList_GetItemRef() limited C API definition (#117520) 2024-04-03 21:02:42 +00:00
lock.h gh-117511: Make PyMutex public in the non-limited API (#117731) 2024-06-20 11:29:08 -04:00
longobject.h gh-117021: Fix integer overflow in PyLong_AsPid() on non-Windows 64-bit platforms (GH-117064) 2024-03-20 15:39:53 +02:00
marshal.h bpo-45474: Exclude all of marshal.h if Py_LIMITED_API is defined (GH-29061) 2021-10-20 02:32:14 -07:00
memoryobject.h gh-79315: Add Include/cpython/memoryobject.h header (#99723) 2022-11-23 15:44:42 +01:00
methodobject.h gh-114626: Add again _PyCFunctionFastWithKeywords name (GH-115561) 2024-02-19 13:20:46 +01:00
modsupport.h gh-112136: Restore removed _PyArg_Parser (#121262) 2024-07-03 18:36:57 +02:00
moduleobject.h gh-116322: Rename PyModule_ExperimentalSetGIL to PyUnstable_Module_SetGIL (GH-118645) 2024-05-06 18:59:36 +02:00
monitoring.h gh-111997: C-API for signalling monitoring events (#116413) 2024-05-04 08:23:50 +00:00
object.h gh-120198: Stop the world when setting __class__ on free-threaded build (GH-120672) 2024-07-11 02:02:08 +08:00
objimpl.h gh-102013: Move PyUnstable_GC_VisitObjects() to Include/cpython/objimpl.h (#115560) 2024-02-16 15:49:13 +01:00
opcode.h gh-105481: opcode.h is no longer generated during the build (#108080) 2023-08-17 17:07:58 +01:00
opcode_ids.h GH-123040: Specialize shadowed LOAD_ATTR. (GH-123219) 2024-08-23 10:22:35 +01:00
osdefs.h gh-108765: Reformat Include/osdefs.h (#108766) 2023-09-01 14:35:39 +00:00
osmodule.h Issue #29058: All stable API extensions added after Python 3.2 are now 2016-12-27 14:57:39 +02:00
patchlevel.h Python 3.14.0a0 2024-05-08 16:57:05 +02:00
py_curses.h gh-113565: Improve and harden detection of curses dependencies (#119816) 2024-07-01 08:10:03 +00:00
pyatomic.h gh-108724: Add PyMutex and _PyParkingLot APIs (gh-109344) 2023-09-19 09:54:29 -06:00
pybuffer.h gh-102500: Implement PEP 688 (#102521) 2023-05-04 07:59:46 -07:00
pycapsule.h gh-108240: Add pycore_capsule.h internal header file (#108596) 2023-08-29 01:20:02 +00:00
pydtrace.d bpo-36842: Implement PEP 578 (GH-12613) 2019-05-23 08:45:22 -07:00
pydtrace.h Fix pydtrace.d path comment in Include/pydtrace.h (#28539) 2022-12-31 22:40:25 +05:30
pyerrors.h gh-119521: Rename IncompleteInputError to _IncompleteInputError and remove from public API/ABI (GH-119680) 2024-06-24 14:08:12 +02:00
pyexpat.h gh-115398: Revert PyExpat_CAPI_MAGIC version bump (GH-116411) 2024-03-06 09:55:07 -08:00
pyframe.h gh-93937, C API: Move PyFrame_GetBack() to Python.h (#93938) 2022-06-19 12:02:33 +02:00
pyhash.h gh-111545: Add Include/cpython/pyhash.h header file (#112063) 2023-11-15 01:19:20 +01:00
pylifecycle.h gh-117987: Restore several functions removed in Python 3.13 alpha 1 (GH-117993) 2024-04-18 15:20:38 +02:00
pymacconfig.h gh-110820: Make sure processor specific defines are correct for Universal 2 build on macOS (#112828) 2023-12-08 10:09:34 +01:00
pymacro.h gh-118124: fix assert related C++ checks on Solaris/Illumos (#121974) 2024-07-21 18:50:14 +02:00
pymath.h gh-119613: Soft deprecate Py_IS_NAN/INFINITY/FINITE (#119701) 2024-05-29 10:45:14 +00:00
pymem.h gh-85283: Add PyMem_RawMalloc() to the limited C API (#108570) 2023-10-17 02:41:51 +02:00
pyport.h gh-121040: Use __attribute__((fallthrough)) (#121044) 2024-06-27 09:58:44 +00:00
pystate.h gh-108867: Add PyThreadState_GetUnchecked() function (#108870) 2023-10-03 16:53:51 +00:00
pystats.h gh-108753: Enhance pystats (#108754) 2023-09-06 15:54:59 +00:00
pystrcmp.h Merged revisions 59541-59561 via svnmerge from 2007-12-19 02:07:34 +00:00
pystrtod.h gh-106320: Remove private float C API functions (#108430) 2023-08-24 19:09:49 +02:00
Python.h gh-120642: Move private PyCode APIs to the internal C API (#120643) 2024-06-26 13:54:03 +02:00
pythonrun.h gh-102755: PyErr_DisplayException only in ABI >= 3.12. Tests cover PyErr_Display as well (GH-102849) 2023-03-21 10:36:18 +01:00
pythread.h gh-81925: Implement native thread ids for kFreeBSD (#111761) 2023-11-09 21:02:30 +01:00
pytypedefs.h bpo-45459: Fix PyModuleDef_Slot type in the limited C API (GH-31668) 2022-03-03 23:06:55 +01:00
rangeobject.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
README.rst gh-101101: Unstable C API tier (PEP 689) (GH-101102) 2023-02-28 09:31:01 +01:00
refcount.h gh-119853: Add Include/refcount.h file (#119854) 2024-05-31 16:49:26 +02:00
setobject.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
sliceobject.h gh-115754: Add Py_GetConstant() function (#116883) 2024-03-21 16:07:00 +00:00
structmember.h Fix typos in comments (#120188) 2024-06-07 10:19:41 +02:00
structseq.h gh-106168: PyTuple_SET_ITEM() now checks the index (#106164) 2023-06-28 03:45:57 +02:00
sysmodule.h gh-117987: Restore several functions removed in Python 3.13 alpha 1 (GH-117993) 2024-04-18 15:20:38 +02:00
traceback.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
tupleobject.h gh-87347: Add parenthesis around PyXXX_Check() arguments (#92815) 2022-06-16 13:49:43 +02:00
typeslots.h bpo-45459: Add Py_buffer to limited API (GH-29991) 2022-02-02 07:03:10 -08:00
unicodeobject.h gh-111089: Revert PyUnicode_AsUTF8() changes (#111833) 2023-11-07 22:36:13 +00:00
warnings.h bpo-35134: Split warnings.h and weakrefobject.h (GH-29042) 2021-10-19 01:31:57 +02:00
weakrefobject.h gh-105927: Limit PyWeakref_GetRef() to limited C API 3.13 (#117091) 2024-03-20 23:52:23 +01:00

The Python C API
================

The C API is divided into these sections:

1. ``Include/``: Limited API
2. ``Include/cpython/``: CPython implementation details
3. ``Include/cpython/``, names with the ``PyUnstable_`` prefix: API that can
   change between minor releases
4. ``Include/internal/``, and any name with ``_`` prefix: The internal API

Information on changing the C API is available `in the developer guide`_

.. _in the developer guide: https://devguide.python.org/c-api/