mirror of
https://github.com/python/cpython
synced 2024-11-02 10:13:47 +00:00
3b3ec0d77f
Rename Py_NOGIL to Py_GIL_DISABLED
1172 lines
43 KiB
C
1172 lines
43 KiB
C
#ifndef Py_OBJECT_H
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#define Py_OBJECT_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* Object and type object interface */
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/*
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Objects are structures allocated on the heap. Special rules apply to
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the use of objects to ensure they are properly garbage-collected.
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Objects are never allocated statically or on the stack; they must be
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accessed through special macros and functions only. (Type objects are
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exceptions to the first rule; the standard types are represented by
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statically initialized type objects, although work on type/class unification
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for Python 2.2 made it possible to have heap-allocated type objects too).
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An object has a 'reference count' that is increased or decreased when a
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pointer to the object is copied or deleted; when the reference count
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reaches zero there are no references to the object left and it can be
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removed from the heap.
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An object has a 'type' that determines what it represents and what kind
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of data it contains. An object's type is fixed when it is created.
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Types themselves are represented as objects; an object contains a
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pointer to the corresponding type object. The type itself has a type
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pointer pointing to the object representing the type 'type', which
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contains a pointer to itself!.
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Objects do not float around in memory; once allocated an object keeps
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the same size and address. Objects that must hold variable-size data
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can contain pointers to variable-size parts of the object. Not all
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objects of the same type have the same size; but the size cannot change
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after allocation. (These restrictions are made so a reference to an
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object can be simply a pointer -- moving an object would require
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updating all the pointers, and changing an object's size would require
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moving it if there was another object right next to it.)
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Objects are always accessed through pointers of the type 'PyObject *'.
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The type 'PyObject' is a structure that only contains the reference count
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and the type pointer. The actual memory allocated for an object
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contains other data that can only be accessed after casting the pointer
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to a pointer to a longer structure type. This longer type must start
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with the reference count and type fields; the macro PyObject_HEAD should be
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used for this (to accommodate for future changes). The implementation
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of a particular object type can cast the object pointer to the proper
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type and back.
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A standard interface exists for objects that contain an array of items
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whose size is determined when the object is allocated.
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*/
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/* Py_DEBUG implies Py_REF_DEBUG. */
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#if defined(Py_DEBUG) && !defined(Py_REF_DEBUG)
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# define Py_REF_DEBUG
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#endif
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/* PyObject_HEAD defines the initial segment of every PyObject. */
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#define PyObject_HEAD PyObject ob_base;
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/*
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Immortalization:
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The following indicates the immortalization strategy depending on the amount
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of available bits in the reference count field. All strategies are backwards
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compatible but the specific reference count value or immortalization check
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might change depending on the specializations for the underlying system.
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Proper deallocation of immortal instances requires distinguishing between
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statically allocated immortal instances vs those promoted by the runtime to be
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immortal. The latter should be the only instances that require
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cleanup during runtime finalization.
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*/
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#if SIZEOF_VOID_P > 4
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/*
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In 64+ bit systems, an object will be marked as immortal by setting all of the
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lower 32 bits of the reference count field, which is equal to: 0xFFFFFFFF
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Using the lower 32 bits makes the value backwards compatible by allowing
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C-Extensions without the updated checks in Py_INCREF and Py_DECREF to safely
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increase and decrease the objects reference count. The object would lose its
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immortality, but the execution would still be correct.
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Reference count increases will use saturated arithmetic, taking advantage of
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having all the lower 32 bits set, which will avoid the reference count to go
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beyond the refcount limit. Immortality checks for reference count decreases will
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be done by checking the bit sign flag in the lower 32 bits.
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*/
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#define _Py_IMMORTAL_REFCNT UINT_MAX
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#else
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/*
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In 32 bit systems, an object will be marked as immortal by setting all of the
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lower 30 bits of the reference count field, which is equal to: 0x3FFFFFFF
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Using the lower 30 bits makes the value backwards compatible by allowing
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C-Extensions without the updated checks in Py_INCREF and Py_DECREF to safely
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increase and decrease the objects reference count. The object would lose its
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immortality, but the execution would still be correct.
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Reference count increases and decreases will first go through an immortality
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check by comparing the reference count field to the immortality reference count.
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*/
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#define _Py_IMMORTAL_REFCNT (UINT_MAX >> 2)
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#endif
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// Py_GIL_DISABLED builds indicate immortal objects using `ob_ref_local`, which is
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// always 32-bits.
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#ifdef Py_GIL_DISABLED
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#define _Py_IMMORTAL_REFCNT_LOCAL UINT32_MAX
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#endif
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// Kept for backward compatibility. It was needed by Py_TRACE_REFS build.
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#define _PyObject_EXTRA_INIT
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// Make all internal uses of PyObject_HEAD_INIT immortal while preserving the
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// C-API expectation that the refcnt will be set to 1.
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#if defined(Py_GIL_DISABLED)
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#define PyObject_HEAD_INIT(type) \
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{ \
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0, \
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0, \
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{ 0 }, \
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0, \
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_Py_IMMORTAL_REFCNT_LOCAL, \
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0, \
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(type), \
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},
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#elif defined(Py_BUILD_CORE)
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#define PyObject_HEAD_INIT(type) \
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{ \
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{ _Py_IMMORTAL_REFCNT }, \
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(type) \
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},
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#else
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#define PyObject_HEAD_INIT(type) \
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{ \
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{ 1 }, \
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(type) \
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},
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#endif /* Py_BUILD_CORE */
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#define PyVarObject_HEAD_INIT(type, size) \
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{ \
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PyObject_HEAD_INIT(type) \
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(size) \
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},
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/* PyObject_VAR_HEAD defines the initial segment of all variable-size
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* container objects. These end with a declaration of an array with 1
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* element, but enough space is malloc'ed so that the array actually
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* has room for ob_size elements. Note that ob_size is an element count,
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* not necessarily a byte count.
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*/
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#define PyObject_VAR_HEAD PyVarObject ob_base;
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#define Py_INVALID_SIZE (Py_ssize_t)-1
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/* Nothing is actually declared to be a PyObject, but every pointer to
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* a Python object can be cast to a PyObject*. This is inheritance built
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* by hand. Similarly every pointer to a variable-size Python object can,
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* in addition, be cast to PyVarObject*.
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*/
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#ifndef Py_GIL_DISABLED
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struct _object {
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#if (defined(__GNUC__) || defined(__clang__)) \
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&& !(defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)
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// On C99 and older, anonymous union is a GCC and clang extension
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__extension__
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#endif
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#ifdef _MSC_VER
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// Ignore MSC warning C4201: "nonstandard extension used:
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// nameless struct/union"
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__pragma(warning(push))
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__pragma(warning(disable: 4201))
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#endif
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union {
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Py_ssize_t ob_refcnt;
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#if SIZEOF_VOID_P > 4
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PY_UINT32_T ob_refcnt_split[2];
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#endif
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};
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#ifdef _MSC_VER
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__pragma(warning(pop))
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#endif
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PyTypeObject *ob_type;
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};
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#else
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// Objects that are not owned by any thread use a thread id (tid) of zero.
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// This includes both immortal objects and objects whose reference count
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// fields have been merged.
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#define _Py_UNOWNED_TID 0
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// The shared reference count uses the two least-significant bits to store
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// flags. The remaining bits are used to store the reference count.
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#define _Py_REF_SHARED_SHIFT 2
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#define _Py_REF_SHARED_FLAG_MASK 0x3
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// The shared flags are initialized to zero.
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#define _Py_REF_SHARED_INIT 0x0
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#define _Py_REF_MAYBE_WEAKREF 0x1
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#define _Py_REF_QUEUED 0x2
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#define _Py_REF_MERGED 0x3
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// Create a shared field from a refcnt and desired flags
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#define _Py_REF_SHARED(refcnt, flags) (((refcnt) << _Py_REF_SHARED_SHIFT) + (flags))
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// NOTE: In non-free-threaded builds, `struct _PyMutex` is defined in
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// pycore_lock.h. See pycore_lock.h for more details.
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struct _PyMutex { uint8_t v; };
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struct _object {
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uintptr_t ob_tid; // thread id (or zero)
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uint16_t _padding;
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struct _PyMutex ob_mutex; // per-object lock
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uint8_t ob_gc_bits; // gc-related state
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uint32_t ob_ref_local; // local reference count
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Py_ssize_t ob_ref_shared; // shared (atomic) reference count
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PyTypeObject *ob_type;
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};
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#endif
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/* Cast argument to PyObject* type. */
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#define _PyObject_CAST(op) _Py_CAST(PyObject*, (op))
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typedef struct {
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PyObject ob_base;
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Py_ssize_t ob_size; /* Number of items in variable part */
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} PyVarObject;
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/* Cast argument to PyVarObject* type. */
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#define _PyVarObject_CAST(op) _Py_CAST(PyVarObject*, (op))
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// Test if the 'x' object is the 'y' object, the same as "x is y" in Python.
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PyAPI_FUNC(int) Py_Is(PyObject *x, PyObject *y);
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#define Py_Is(x, y) ((x) == (y))
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#if defined(Py_GIL_DISABLED) && !defined(Py_LIMITED_API)
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static inline uintptr_t
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_Py_ThreadId(void)
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{
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uintptr_t tid;
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#if defined(_MSC_VER) && defined(_M_X64)
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tid = __readgsqword(48);
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#elif defined(_MSC_VER) && defined(_M_IX86)
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tid = __readfsdword(24);
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#elif defined(_MSC_VER) && defined(_M_ARM64)
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tid = __getReg(18);
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#elif defined(__i386__)
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__asm__("movl %%gs:0, %0" : "=r" (tid)); // 32-bit always uses GS
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#elif defined(__MACH__) && defined(__x86_64__)
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__asm__("movq %%gs:0, %0" : "=r" (tid)); // x86_64 macOSX uses GS
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#elif defined(__x86_64__)
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__asm__("movq %%fs:0, %0" : "=r" (tid)); // x86_64 Linux, BSD uses FS
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#elif defined(__arm__)
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__asm__ ("mrc p15, 0, %0, c13, c0, 3\nbic %0, %0, #3" : "=r" (tid));
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#elif defined(__aarch64__) && defined(__APPLE__)
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__asm__ ("mrs %0, tpidrro_el0" : "=r" (tid));
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#elif defined(__aarch64__)
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__asm__ ("mrs %0, tpidr_el0" : "=r" (tid));
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#else
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# error "define _Py_ThreadId for this platform"
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#endif
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return tid;
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}
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static inline Py_ALWAYS_INLINE int
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_Py_IsOwnedByCurrentThread(PyObject *ob)
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{
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return ob->ob_tid == _Py_ThreadId();
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}
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#endif
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static inline Py_ssize_t Py_REFCNT(PyObject *ob) {
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#if !defined(Py_GIL_DISABLED)
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return ob->ob_refcnt;
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#else
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uint32_t local = _Py_atomic_load_uint32_relaxed(&ob->ob_ref_local);
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if (local == _Py_IMMORTAL_REFCNT_LOCAL) {
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return _Py_IMMORTAL_REFCNT;
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}
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Py_ssize_t shared = _Py_atomic_load_ssize_relaxed(&ob->ob_ref_shared);
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return _Py_STATIC_CAST(Py_ssize_t, local) +
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Py_ARITHMETIC_RIGHT_SHIFT(Py_ssize_t, shared, _Py_REF_SHARED_SHIFT);
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#endif
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_REFCNT(ob) Py_REFCNT(_PyObject_CAST(ob))
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#endif
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// bpo-39573: The Py_SET_TYPE() function must be used to set an object type.
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static inline PyTypeObject* Py_TYPE(PyObject *ob) {
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return ob->ob_type;
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_TYPE(ob) Py_TYPE(_PyObject_CAST(ob))
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#endif
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PyAPI_DATA(PyTypeObject) PyLong_Type;
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PyAPI_DATA(PyTypeObject) PyBool_Type;
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// bpo-39573: The Py_SET_SIZE() function must be used to set an object size.
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static inline Py_ssize_t Py_SIZE(PyObject *ob) {
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assert(ob->ob_type != &PyLong_Type);
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assert(ob->ob_type != &PyBool_Type);
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PyVarObject *var_ob = _PyVarObject_CAST(ob);
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return var_ob->ob_size;
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_SIZE(ob) Py_SIZE(_PyObject_CAST(ob))
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#endif
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static inline Py_ALWAYS_INLINE int _Py_IsImmortal(PyObject *op)
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{
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#if defined(Py_GIL_DISABLED)
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return op->ob_ref_local == _Py_IMMORTAL_REFCNT_LOCAL;
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#elif SIZEOF_VOID_P > 4
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return _Py_CAST(PY_INT32_T, op->ob_refcnt) < 0;
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#else
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return op->ob_refcnt == _Py_IMMORTAL_REFCNT;
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#endif
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}
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#define _Py_IsImmortal(op) _Py_IsImmortal(_PyObject_CAST(op))
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static inline int Py_IS_TYPE(PyObject *ob, PyTypeObject *type) {
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return Py_TYPE(ob) == type;
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_IS_TYPE(ob, type) Py_IS_TYPE(_PyObject_CAST(ob), (type))
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#endif
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// Py_SET_REFCNT() implementation for stable ABI
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PyAPI_FUNC(void) _Py_SetRefcnt(PyObject *ob, Py_ssize_t refcnt);
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static inline void Py_SET_REFCNT(PyObject *ob, Py_ssize_t refcnt) {
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#if defined(Py_LIMITED_API) && Py_LIMITED_API+0 >= 0x030d0000
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// Stable ABI implements Py_SET_REFCNT() as a function call
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// on limited C API version 3.13 and newer.
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_Py_SetRefcnt(ob, refcnt);
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#else
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// This immortal check is for code that is unaware of immortal objects.
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// The runtime tracks these objects and we should avoid as much
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// as possible having extensions inadvertently change the refcnt
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// of an immortalized object.
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if (_Py_IsImmortal(ob)) {
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return;
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}
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#ifndef Py_GIL_DISABLED
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ob->ob_refcnt = refcnt;
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#else
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if (_Py_IsOwnedByCurrentThread(ob)) {
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// Set local refcount to desired refcount and shared refcount to zero,
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// but preserve the shared refcount flags.
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assert(refcnt < UINT32_MAX);
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ob->ob_ref_local = _Py_STATIC_CAST(uint32_t, refcnt);
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ob->ob_ref_shared &= _Py_REF_SHARED_FLAG_MASK;
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}
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else {
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// Set local refcount to zero and shared refcount to desired refcount.
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// Mark the object as merged.
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ob->ob_tid = _Py_UNOWNED_TID;
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ob->ob_ref_local = 0;
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ob->ob_ref_shared = _Py_REF_SHARED(refcnt, _Py_REF_MERGED);
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}
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#endif // Py_GIL_DISABLED
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#endif // Py_LIMITED_API+0 < 0x030d0000
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_SET_REFCNT(ob, refcnt) Py_SET_REFCNT(_PyObject_CAST(ob), (refcnt))
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#endif
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static inline void Py_SET_TYPE(PyObject *ob, PyTypeObject *type) {
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ob->ob_type = type;
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_SET_TYPE(ob, type) Py_SET_TYPE(_PyObject_CAST(ob), type)
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#endif
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static inline void Py_SET_SIZE(PyVarObject *ob, Py_ssize_t size) {
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assert(ob->ob_base.ob_type != &PyLong_Type);
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assert(ob->ob_base.ob_type != &PyBool_Type);
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ob->ob_size = size;
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}
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
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# define Py_SET_SIZE(ob, size) Py_SET_SIZE(_PyVarObject_CAST(ob), (size))
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#endif
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/*
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Type objects contain a string containing the type name (to help somewhat
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in debugging), the allocation parameters (see PyObject_New() and
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PyObject_NewVar()),
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and methods for accessing objects of the type. Methods are optional, a
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nil pointer meaning that particular kind of access is not available for
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this type. The Py_DECREF() macro uses the tp_dealloc method without
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checking for a nil pointer; it should always be implemented except if
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the implementation can guarantee that the reference count will never
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reach zero (e.g., for statically allocated type objects).
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NB: the methods for certain type groups are now contained in separate
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method blocks.
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*/
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typedef PyObject * (*unaryfunc)(PyObject *);
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typedef PyObject * (*binaryfunc)(PyObject *, PyObject *);
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typedef PyObject * (*ternaryfunc)(PyObject *, PyObject *, PyObject *);
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typedef int (*inquiry)(PyObject *);
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typedef Py_ssize_t (*lenfunc)(PyObject *);
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typedef PyObject *(*ssizeargfunc)(PyObject *, Py_ssize_t);
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typedef PyObject *(*ssizessizeargfunc)(PyObject *, Py_ssize_t, Py_ssize_t);
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typedef int(*ssizeobjargproc)(PyObject *, Py_ssize_t, PyObject *);
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typedef int(*ssizessizeobjargproc)(PyObject *, Py_ssize_t, Py_ssize_t, PyObject *);
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typedef int(*objobjargproc)(PyObject *, PyObject *, PyObject *);
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typedef int (*objobjproc)(PyObject *, PyObject *);
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typedef int (*visitproc)(PyObject *, void *);
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typedef int (*traverseproc)(PyObject *, visitproc, void *);
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typedef void (*freefunc)(void *);
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typedef void (*destructor)(PyObject *);
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typedef PyObject *(*getattrfunc)(PyObject *, char *);
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typedef PyObject *(*getattrofunc)(PyObject *, PyObject *);
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typedef int (*setattrfunc)(PyObject *, char *, PyObject *);
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typedef int (*setattrofunc)(PyObject *, PyObject *, PyObject *);
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typedef PyObject *(*reprfunc)(PyObject *);
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typedef Py_hash_t (*hashfunc)(PyObject *);
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typedef PyObject *(*richcmpfunc) (PyObject *, PyObject *, int);
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typedef PyObject *(*getiterfunc) (PyObject *);
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typedef PyObject *(*iternextfunc) (PyObject *);
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typedef PyObject *(*descrgetfunc) (PyObject *, PyObject *, PyObject *);
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typedef int (*descrsetfunc) (PyObject *, PyObject *, PyObject *);
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typedef int (*initproc)(PyObject *, PyObject *, PyObject *);
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typedef PyObject *(*newfunc)(PyTypeObject *, PyObject *, PyObject *);
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typedef PyObject *(*allocfunc)(PyTypeObject *, Py_ssize_t);
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030c0000 // 3.12
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typedef PyObject *(*vectorcallfunc)(PyObject *callable, PyObject *const *args,
|
|
size_t nargsf, PyObject *kwnames);
|
|
#endif
|
|
|
|
typedef struct{
|
|
int slot; /* slot id, see below */
|
|
void *pfunc; /* function pointer */
|
|
} PyType_Slot;
|
|
|
|
typedef struct{
|
|
const char* name;
|
|
int basicsize;
|
|
int itemsize;
|
|
unsigned int flags;
|
|
PyType_Slot *slots; /* terminated by slot==0. */
|
|
} PyType_Spec;
|
|
|
|
PyAPI_FUNC(PyObject*) PyType_FromSpec(PyType_Spec*);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
|
|
PyAPI_FUNC(PyObject*) PyType_FromSpecWithBases(PyType_Spec*, PyObject*);
|
|
#endif
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03040000
|
|
PyAPI_FUNC(void*) PyType_GetSlot(PyTypeObject*, int);
|
|
#endif
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03090000
|
|
PyAPI_FUNC(PyObject*) PyType_FromModuleAndSpec(PyObject *, PyType_Spec *, PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyType_GetModule(PyTypeObject *);
|
|
PyAPI_FUNC(void *) PyType_GetModuleState(PyTypeObject *);
|
|
#endif
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030B0000
|
|
PyAPI_FUNC(PyObject *) PyType_GetName(PyTypeObject *);
|
|
PyAPI_FUNC(PyObject *) PyType_GetQualName(PyTypeObject *);
|
|
#endif
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030C0000
|
|
PyAPI_FUNC(PyObject *) PyType_FromMetaclass(PyTypeObject*, PyObject*, PyType_Spec*, PyObject*);
|
|
PyAPI_FUNC(void *) PyObject_GetTypeData(PyObject *obj, PyTypeObject *cls);
|
|
PyAPI_FUNC(Py_ssize_t) PyType_GetTypeDataSize(PyTypeObject *cls);
|
|
#endif
|
|
|
|
/* Generic type check */
|
|
PyAPI_FUNC(int) PyType_IsSubtype(PyTypeObject *, PyTypeObject *);
|
|
|
|
static inline int PyObject_TypeCheck(PyObject *ob, PyTypeObject *type) {
|
|
return Py_IS_TYPE(ob, type) || PyType_IsSubtype(Py_TYPE(ob), type);
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define PyObject_TypeCheck(ob, type) PyObject_TypeCheck(_PyObject_CAST(ob), (type))
|
|
#endif
|
|
|
|
PyAPI_DATA(PyTypeObject) PyType_Type; /* built-in 'type' */
|
|
PyAPI_DATA(PyTypeObject) PyBaseObject_Type; /* built-in 'object' */
|
|
PyAPI_DATA(PyTypeObject) PySuper_Type; /* built-in 'super' */
|
|
|
|
PyAPI_FUNC(unsigned long) PyType_GetFlags(PyTypeObject*);
|
|
|
|
PyAPI_FUNC(int) PyType_Ready(PyTypeObject *);
|
|
PyAPI_FUNC(PyObject *) PyType_GenericAlloc(PyTypeObject *, Py_ssize_t);
|
|
PyAPI_FUNC(PyObject *) PyType_GenericNew(PyTypeObject *,
|
|
PyObject *, PyObject *);
|
|
PyAPI_FUNC(unsigned int) PyType_ClearCache(void);
|
|
PyAPI_FUNC(void) PyType_Modified(PyTypeObject *);
|
|
|
|
/* Generic operations on objects */
|
|
PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_ASCII(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_Bytes(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int);
|
|
PyAPI_FUNC(int) PyObject_RichCompareBool(PyObject *, PyObject *, int);
|
|
PyAPI_FUNC(PyObject *) PyObject_GetAttrString(PyObject *, const char *);
|
|
PyAPI_FUNC(int) PyObject_SetAttrString(PyObject *, const char *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_DelAttrString(PyObject *v, const char *name);
|
|
PyAPI_FUNC(int) PyObject_HasAttrString(PyObject *, const char *);
|
|
PyAPI_FUNC(PyObject *) PyObject_GetAttr(PyObject *, PyObject *);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030d0000
|
|
PyAPI_FUNC(int) PyObject_GetOptionalAttr(PyObject *, PyObject *, PyObject **);
|
|
PyAPI_FUNC(int) PyObject_GetOptionalAttrString(PyObject *, const char *, PyObject **);
|
|
#endif
|
|
PyAPI_FUNC(int) PyObject_SetAttr(PyObject *, PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_DelAttr(PyObject *v, PyObject *name);
|
|
PyAPI_FUNC(int) PyObject_HasAttr(PyObject *, PyObject *);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030d0000
|
|
PyAPI_FUNC(int) PyObject_HasAttrWithError(PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_HasAttrStringWithError(PyObject *, const char *);
|
|
#endif
|
|
PyAPI_FUNC(PyObject *) PyObject_SelfIter(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_GenericSetAttr(PyObject *, PyObject *, PyObject *);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
|
|
PyAPI_FUNC(int) PyObject_GenericSetDict(PyObject *, PyObject *, void *);
|
|
#endif
|
|
PyAPI_FUNC(Py_hash_t) PyObject_Hash(PyObject *);
|
|
PyAPI_FUNC(Py_hash_t) PyObject_HashNotImplemented(PyObject *);
|
|
PyAPI_FUNC(int) PyObject_IsTrue(PyObject *);
|
|
PyAPI_FUNC(int) PyObject_Not(PyObject *);
|
|
PyAPI_FUNC(int) PyCallable_Check(PyObject *);
|
|
PyAPI_FUNC(void) PyObject_ClearWeakRefs(PyObject *);
|
|
|
|
/* PyObject_Dir(obj) acts like Python builtins.dir(obj), returning a
|
|
list of strings. PyObject_Dir(NULL) is like builtins.dir(),
|
|
returning the names of the current locals. In this case, if there are
|
|
no current locals, NULL is returned, and PyErr_Occurred() is false.
|
|
*/
|
|
PyAPI_FUNC(PyObject *) PyObject_Dir(PyObject *);
|
|
|
|
/* Helpers for printing recursive container types */
|
|
PyAPI_FUNC(int) Py_ReprEnter(PyObject *);
|
|
PyAPI_FUNC(void) Py_ReprLeave(PyObject *);
|
|
|
|
/* Flag bits for printing: */
|
|
#define Py_PRINT_RAW 1 /* No string quotes etc. */
|
|
|
|
/*
|
|
Type flags (tp_flags)
|
|
|
|
These flags are used to change expected features and behavior for a
|
|
particular type.
|
|
|
|
Arbitration of the flag bit positions will need to be coordinated among
|
|
all extension writers who publicly release their extensions (this will
|
|
be fewer than you might expect!).
|
|
|
|
Most flags were removed as of Python 3.0 to make room for new flags. (Some
|
|
flags are not for backwards compatibility but to indicate the presence of an
|
|
optional feature; these flags remain of course.)
|
|
|
|
Type definitions should use Py_TPFLAGS_DEFAULT for their tp_flags value.
|
|
|
|
Code can use PyType_HasFeature(type_ob, flag_value) to test whether the
|
|
given type object has a specified feature.
|
|
*/
|
|
|
|
#ifndef Py_LIMITED_API
|
|
|
|
/* Track types initialized using _PyStaticType_InitBuiltin(). */
|
|
#define _Py_TPFLAGS_STATIC_BUILTIN (1 << 1)
|
|
|
|
/* Placement of weakref pointers are managed by the VM, not by the type.
|
|
* The VM will automatically set tp_weaklistoffset.
|
|
*/
|
|
#define Py_TPFLAGS_MANAGED_WEAKREF (1 << 3)
|
|
|
|
/* Placement of dict (and values) pointers are managed by the VM, not by the type.
|
|
* The VM will automatically set tp_dictoffset.
|
|
*/
|
|
#define Py_TPFLAGS_MANAGED_DICT (1 << 4)
|
|
|
|
#define Py_TPFLAGS_PREHEADER (Py_TPFLAGS_MANAGED_WEAKREF | Py_TPFLAGS_MANAGED_DICT)
|
|
|
|
/* Set if instances of the type object are treated as sequences for pattern matching */
|
|
#define Py_TPFLAGS_SEQUENCE (1 << 5)
|
|
/* Set if instances of the type object are treated as mappings for pattern matching */
|
|
#define Py_TPFLAGS_MAPPING (1 << 6)
|
|
#endif
|
|
|
|
/* Disallow creating instances of the type: set tp_new to NULL and don't create
|
|
* the "__new__" key in the type dictionary. */
|
|
#define Py_TPFLAGS_DISALLOW_INSTANTIATION (1UL << 7)
|
|
|
|
/* Set if the type object is immutable: type attributes cannot be set nor deleted */
|
|
#define Py_TPFLAGS_IMMUTABLETYPE (1UL << 8)
|
|
|
|
/* Set if the type object is dynamically allocated */
|
|
#define Py_TPFLAGS_HEAPTYPE (1UL << 9)
|
|
|
|
/* Set if the type allows subclassing */
|
|
#define Py_TPFLAGS_BASETYPE (1UL << 10)
|
|
|
|
/* Set if the type implements the vectorcall protocol (PEP 590) */
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030C0000
|
|
#define Py_TPFLAGS_HAVE_VECTORCALL (1UL << 11)
|
|
#ifndef Py_LIMITED_API
|
|
// Backwards compatibility alias for API that was provisional in Python 3.8
|
|
#define _Py_TPFLAGS_HAVE_VECTORCALL Py_TPFLAGS_HAVE_VECTORCALL
|
|
#endif
|
|
#endif
|
|
|
|
/* Set if the type is 'ready' -- fully initialized */
|
|
#define Py_TPFLAGS_READY (1UL << 12)
|
|
|
|
/* Set while the type is being 'readied', to prevent recursive ready calls */
|
|
#define Py_TPFLAGS_READYING (1UL << 13)
|
|
|
|
/* Objects support garbage collection (see objimpl.h) */
|
|
#define Py_TPFLAGS_HAVE_GC (1UL << 14)
|
|
|
|
/* These two bits are preserved for Stackless Python, next after this is 17 */
|
|
#ifdef STACKLESS
|
|
#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION (3UL << 15)
|
|
#else
|
|
#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION 0
|
|
#endif
|
|
|
|
/* Objects behave like an unbound method */
|
|
#define Py_TPFLAGS_METHOD_DESCRIPTOR (1UL << 17)
|
|
|
|
/* Object has up-to-date type attribute cache */
|
|
#define Py_TPFLAGS_VALID_VERSION_TAG (1UL << 19)
|
|
|
|
/* Type is abstract and cannot be instantiated */
|
|
#define Py_TPFLAGS_IS_ABSTRACT (1UL << 20)
|
|
|
|
// This undocumented flag gives certain built-ins their unique pattern-matching
|
|
// behavior, which allows a single positional subpattern to match against the
|
|
// subject itself (rather than a mapped attribute on it):
|
|
#define _Py_TPFLAGS_MATCH_SELF (1UL << 22)
|
|
|
|
/* Items (ob_size*tp_itemsize) are found at the end of an instance's memory */
|
|
#define Py_TPFLAGS_ITEMS_AT_END (1UL << 23)
|
|
|
|
/* These flags are used to determine if a type is a subclass. */
|
|
#define Py_TPFLAGS_LONG_SUBCLASS (1UL << 24)
|
|
#define Py_TPFLAGS_LIST_SUBCLASS (1UL << 25)
|
|
#define Py_TPFLAGS_TUPLE_SUBCLASS (1UL << 26)
|
|
#define Py_TPFLAGS_BYTES_SUBCLASS (1UL << 27)
|
|
#define Py_TPFLAGS_UNICODE_SUBCLASS (1UL << 28)
|
|
#define Py_TPFLAGS_DICT_SUBCLASS (1UL << 29)
|
|
#define Py_TPFLAGS_BASE_EXC_SUBCLASS (1UL << 30)
|
|
#define Py_TPFLAGS_TYPE_SUBCLASS (1UL << 31)
|
|
|
|
#define Py_TPFLAGS_DEFAULT ( \
|
|
Py_TPFLAGS_HAVE_STACKLESS_EXTENSION | \
|
|
0)
|
|
|
|
/* NOTE: Some of the following flags reuse lower bits (removed as part of the
|
|
* Python 3.0 transition). */
|
|
|
|
/* The following flags are kept for compatibility; in previous
|
|
* versions they indicated presence of newer tp_* fields on the
|
|
* type struct.
|
|
* Starting with 3.8, binary compatibility of C extensions across
|
|
* feature releases of Python is not supported anymore (except when
|
|
* using the stable ABI, in which all classes are created dynamically,
|
|
* using the interpreter's memory layout.)
|
|
* Note that older extensions using the stable ABI set these flags,
|
|
* so the bits must not be repurposed.
|
|
*/
|
|
#define Py_TPFLAGS_HAVE_FINALIZE (1UL << 0)
|
|
#define Py_TPFLAGS_HAVE_VERSION_TAG (1UL << 18)
|
|
|
|
|
|
/*
|
|
The macros Py_INCREF(op) and Py_DECREF(op) are used to increment or decrement
|
|
reference counts. Py_DECREF calls the object's deallocator function when
|
|
the refcount falls to 0; for
|
|
objects that don't contain references to other objects or heap memory
|
|
this can be the standard function free(). Both macros can be used
|
|
wherever a void expression is allowed. The argument must not be a
|
|
NULL pointer. If it may be NULL, use Py_XINCREF/Py_XDECREF instead.
|
|
The macro _Py_NewReference(op) initialize reference counts to 1, and
|
|
in special builds (Py_REF_DEBUG, Py_TRACE_REFS) performs additional
|
|
bookkeeping appropriate to the special build.
|
|
|
|
We assume that the reference count field can never overflow; this can
|
|
be proven when the size of the field is the same as the pointer size, so
|
|
we ignore the possibility. Provided a C int is at least 32 bits (which
|
|
is implicitly assumed in many parts of this code), that's enough for
|
|
about 2**31 references to an object.
|
|
|
|
XXX The following became out of date in Python 2.2, but I'm not sure
|
|
XXX what the full truth is now. Certainly, heap-allocated type objects
|
|
XXX can and should be deallocated.
|
|
Type objects should never be deallocated; the type pointer in an object
|
|
is not considered to be a reference to the type object, to save
|
|
complications in the deallocation function. (This is actually a
|
|
decision that's up to the implementer of each new type so if you want,
|
|
you can count such references to the type object.)
|
|
*/
|
|
|
|
#if defined(Py_REF_DEBUG) && !defined(Py_LIMITED_API)
|
|
PyAPI_FUNC(void) _Py_NegativeRefcount(const char *filename, int lineno,
|
|
PyObject *op);
|
|
PyAPI_FUNC(void) _Py_INCREF_IncRefTotal(void);
|
|
PyAPI_FUNC(void) _Py_DECREF_DecRefTotal(void);
|
|
#endif // Py_REF_DEBUG && !Py_LIMITED_API
|
|
|
|
PyAPI_FUNC(void) _Py_Dealloc(PyObject *);
|
|
|
|
/*
|
|
These are provided as conveniences to Python runtime embedders, so that
|
|
they can have object code that is not dependent on Python compilation flags.
|
|
*/
|
|
PyAPI_FUNC(void) Py_IncRef(PyObject *);
|
|
PyAPI_FUNC(void) Py_DecRef(PyObject *);
|
|
|
|
// Similar to Py_IncRef() and Py_DecRef() but the argument must be non-NULL.
|
|
// Private functions used by Py_INCREF() and Py_DECREF().
|
|
PyAPI_FUNC(void) _Py_IncRef(PyObject *);
|
|
PyAPI_FUNC(void) _Py_DecRef(PyObject *);
|
|
|
|
static inline Py_ALWAYS_INLINE void Py_INCREF(PyObject *op)
|
|
{
|
|
#if defined(Py_LIMITED_API) && (Py_LIMITED_API+0 >= 0x030c0000 || defined(Py_REF_DEBUG))
|
|
// Stable ABI implements Py_INCREF() as a function call on limited C API
|
|
// version 3.12 and newer, and on Python built in debug mode. _Py_IncRef()
|
|
// was added to Python 3.10.0a7, use Py_IncRef() on older Python versions.
|
|
// Py_IncRef() accepts NULL whereas _Py_IncRef() doesn't.
|
|
# if Py_LIMITED_API+0 >= 0x030a00A7
|
|
_Py_IncRef(op);
|
|
# else
|
|
Py_IncRef(op);
|
|
# endif
|
|
#else
|
|
// Non-limited C API and limited C API for Python 3.9 and older access
|
|
// directly PyObject.ob_refcnt.
|
|
#if defined(Py_GIL_DISABLED)
|
|
uint32_t local = _Py_atomic_load_uint32_relaxed(&op->ob_ref_local);
|
|
uint32_t new_local = local + 1;
|
|
if (new_local == 0) {
|
|
return;
|
|
}
|
|
if (_Py_IsOwnedByCurrentThread(op)) {
|
|
_Py_atomic_store_uint32_relaxed(&op->ob_ref_local, new_local);
|
|
}
|
|
else {
|
|
_Py_atomic_add_ssize(&op->ob_ref_shared, (1 << _Py_REF_SHARED_SHIFT));
|
|
}
|
|
#elif SIZEOF_VOID_P > 4
|
|
// Portable saturated add, branching on the carry flag and set low bits
|
|
PY_UINT32_T cur_refcnt = op->ob_refcnt_split[PY_BIG_ENDIAN];
|
|
PY_UINT32_T new_refcnt = cur_refcnt + 1;
|
|
if (new_refcnt == 0) {
|
|
return;
|
|
}
|
|
op->ob_refcnt_split[PY_BIG_ENDIAN] = new_refcnt;
|
|
#else
|
|
// Explicitly check immortality against the immortal value
|
|
if (_Py_IsImmortal(op)) {
|
|
return;
|
|
}
|
|
op->ob_refcnt++;
|
|
#endif
|
|
_Py_INCREF_STAT_INC();
|
|
#ifdef Py_REF_DEBUG
|
|
_Py_INCREF_IncRefTotal();
|
|
#endif
|
|
#endif
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define Py_INCREF(op) Py_INCREF(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
|
|
#if !defined(Py_LIMITED_API) && defined(Py_GIL_DISABLED)
|
|
// Implements Py_DECREF on objects not owned by the current thread.
|
|
PyAPI_FUNC(void) _Py_DecRefShared(PyObject *);
|
|
PyAPI_FUNC(void) _Py_DecRefSharedDebug(PyObject *, const char *, int);
|
|
|
|
// Called from Py_DECREF by the owning thread when the local refcount reaches
|
|
// zero. The call will deallocate the object if the shared refcount is also
|
|
// zero. Otherwise, the thread gives up ownership and merges the reference
|
|
// count fields.
|
|
PyAPI_FUNC(void) _Py_MergeZeroLocalRefcount(PyObject *);
|
|
#endif
|
|
|
|
#if defined(Py_LIMITED_API) && (Py_LIMITED_API+0 >= 0x030c0000 || defined(Py_REF_DEBUG))
|
|
// Stable ABI implements Py_DECREF() as a function call on limited C API
|
|
// version 3.12 and newer, and on Python built in debug mode. _Py_DecRef() was
|
|
// added to Python 3.10.0a7, use Py_DecRef() on older Python versions.
|
|
// Py_DecRef() accepts NULL whereas _Py_IncRef() doesn't.
|
|
static inline void Py_DECREF(PyObject *op) {
|
|
# if Py_LIMITED_API+0 >= 0x030a00A7
|
|
_Py_DecRef(op);
|
|
# else
|
|
Py_DecRef(op);
|
|
# endif
|
|
}
|
|
#define Py_DECREF(op) Py_DECREF(_PyObject_CAST(op))
|
|
|
|
#elif defined(Py_GIL_DISABLED) && defined(Py_REF_DEBUG)
|
|
static inline void Py_DECREF(const char *filename, int lineno, PyObject *op)
|
|
{
|
|
uint32_t local = _Py_atomic_load_uint32_relaxed(&op->ob_ref_local);
|
|
if (local == _Py_IMMORTAL_REFCNT_LOCAL) {
|
|
return;
|
|
}
|
|
_Py_DECREF_STAT_INC();
|
|
_Py_DECREF_DecRefTotal();
|
|
if (_Py_IsOwnedByCurrentThread(op)) {
|
|
if (local == 0) {
|
|
_Py_NegativeRefcount(filename, lineno, op);
|
|
}
|
|
local--;
|
|
_Py_atomic_store_uint32_relaxed(&op->ob_ref_local, local);
|
|
if (local == 0) {
|
|
_Py_MergeZeroLocalRefcount(op);
|
|
}
|
|
}
|
|
else {
|
|
_Py_DecRefSharedDebug(op, filename, lineno);
|
|
}
|
|
}
|
|
#define Py_DECREF(op) Py_DECREF(__FILE__, __LINE__, _PyObject_CAST(op))
|
|
|
|
#elif defined(Py_GIL_DISABLED)
|
|
static inline void Py_DECREF(PyObject *op)
|
|
{
|
|
uint32_t local = _Py_atomic_load_uint32_relaxed(&op->ob_ref_local);
|
|
if (local == _Py_IMMORTAL_REFCNT_LOCAL) {
|
|
return;
|
|
}
|
|
_Py_DECREF_STAT_INC();
|
|
if (_Py_IsOwnedByCurrentThread(op)) {
|
|
local--;
|
|
_Py_atomic_store_uint32_relaxed(&op->ob_ref_local, local);
|
|
if (local == 0) {
|
|
_Py_MergeZeroLocalRefcount(op);
|
|
}
|
|
}
|
|
else {
|
|
_Py_DecRefShared(op);
|
|
}
|
|
}
|
|
#define Py_DECREF(op) Py_DECREF(_PyObject_CAST(op))
|
|
|
|
#elif defined(Py_REF_DEBUG)
|
|
static inline void Py_DECREF(const char *filename, int lineno, PyObject *op)
|
|
{
|
|
if (op->ob_refcnt <= 0) {
|
|
_Py_NegativeRefcount(filename, lineno, op);
|
|
}
|
|
if (_Py_IsImmortal(op)) {
|
|
return;
|
|
}
|
|
_Py_DECREF_STAT_INC();
|
|
_Py_DECREF_DecRefTotal();
|
|
if (--op->ob_refcnt == 0) {
|
|
_Py_Dealloc(op);
|
|
}
|
|
}
|
|
#define Py_DECREF(op) Py_DECREF(__FILE__, __LINE__, _PyObject_CAST(op))
|
|
|
|
#else
|
|
static inline Py_ALWAYS_INLINE void Py_DECREF(PyObject *op)
|
|
{
|
|
// Non-limited C API and limited C API for Python 3.9 and older access
|
|
// directly PyObject.ob_refcnt.
|
|
if (_Py_IsImmortal(op)) {
|
|
return;
|
|
}
|
|
_Py_DECREF_STAT_INC();
|
|
if (--op->ob_refcnt == 0) {
|
|
_Py_Dealloc(op);
|
|
}
|
|
}
|
|
#define Py_DECREF(op) Py_DECREF(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
|
|
/* Safely decref `op` and set `op` to NULL, especially useful in tp_clear
|
|
* and tp_dealloc implementations.
|
|
*
|
|
* Note that "the obvious" code can be deadly:
|
|
*
|
|
* Py_XDECREF(op);
|
|
* op = NULL;
|
|
*
|
|
* Typically, `op` is something like self->containee, and `self` is done
|
|
* using its `containee` member. In the code sequence above, suppose
|
|
* `containee` is non-NULL with a refcount of 1. Its refcount falls to
|
|
* 0 on the first line, which can trigger an arbitrary amount of code,
|
|
* possibly including finalizers (like __del__ methods or weakref callbacks)
|
|
* coded in Python, which in turn can release the GIL and allow other threads
|
|
* to run, etc. Such code may even invoke methods of `self` again, or cause
|
|
* cyclic gc to trigger, but-- oops! --self->containee still points to the
|
|
* object being torn down, and it may be in an insane state while being torn
|
|
* down. This has in fact been a rich historic source of miserable (rare &
|
|
* hard-to-diagnose) segfaulting (and other) bugs.
|
|
*
|
|
* The safe way is:
|
|
*
|
|
* Py_CLEAR(op);
|
|
*
|
|
* That arranges to set `op` to NULL _before_ decref'ing, so that any code
|
|
* triggered as a side-effect of `op` getting torn down no longer believes
|
|
* `op` points to a valid object.
|
|
*
|
|
* There are cases where it's safe to use the naive code, but they're brittle.
|
|
* For example, if `op` points to a Python integer, you know that destroying
|
|
* one of those can't cause problems -- but in part that relies on that
|
|
* Python integers aren't currently weakly referencable. Best practice is
|
|
* to use Py_CLEAR() even if you can't think of a reason for why you need to.
|
|
*
|
|
* gh-98724: Use a temporary variable to only evaluate the macro argument once,
|
|
* to avoid the duplication of side effects if the argument has side effects.
|
|
*
|
|
* gh-99701: If the PyObject* type is used with casting arguments to PyObject*,
|
|
* the code can be miscompiled with strict aliasing because of type punning.
|
|
* With strict aliasing, a compiler considers that two pointers of different
|
|
* types cannot read or write the same memory which enables optimization
|
|
* opportunities.
|
|
*
|
|
* If available, use _Py_TYPEOF() to use the 'op' type for temporary variables,
|
|
* and so avoid type punning. Otherwise, use memcpy() which causes type erasure
|
|
* and so prevents the compiler to reuse an old cached 'op' value after
|
|
* Py_CLEAR().
|
|
*/
|
|
#ifdef _Py_TYPEOF
|
|
#define Py_CLEAR(op) \
|
|
do { \
|
|
_Py_TYPEOF(op)* _tmp_op_ptr = &(op); \
|
|
_Py_TYPEOF(op) _tmp_old_op = (*_tmp_op_ptr); \
|
|
if (_tmp_old_op != NULL) { \
|
|
*_tmp_op_ptr = _Py_NULL; \
|
|
Py_DECREF(_tmp_old_op); \
|
|
} \
|
|
} while (0)
|
|
#else
|
|
#define Py_CLEAR(op) \
|
|
do { \
|
|
PyObject **_tmp_op_ptr = _Py_CAST(PyObject**, &(op)); \
|
|
PyObject *_tmp_old_op = (*_tmp_op_ptr); \
|
|
if (_tmp_old_op != NULL) { \
|
|
PyObject *_null_ptr = _Py_NULL; \
|
|
memcpy(_tmp_op_ptr, &_null_ptr, sizeof(PyObject*)); \
|
|
Py_DECREF(_tmp_old_op); \
|
|
} \
|
|
} while (0)
|
|
#endif
|
|
|
|
|
|
/* Function to use in case the object pointer can be NULL: */
|
|
static inline void Py_XINCREF(PyObject *op)
|
|
{
|
|
if (op != _Py_NULL) {
|
|
Py_INCREF(op);
|
|
}
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define Py_XINCREF(op) Py_XINCREF(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
static inline void Py_XDECREF(PyObject *op)
|
|
{
|
|
if (op != _Py_NULL) {
|
|
Py_DECREF(op);
|
|
}
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define Py_XDECREF(op) Py_XDECREF(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
// Create a new strong reference to an object:
|
|
// increment the reference count of the object and return the object.
|
|
PyAPI_FUNC(PyObject*) Py_NewRef(PyObject *obj);
|
|
|
|
// Similar to Py_NewRef(), but the object can be NULL.
|
|
PyAPI_FUNC(PyObject*) Py_XNewRef(PyObject *obj);
|
|
|
|
static inline PyObject* _Py_NewRef(PyObject *obj)
|
|
{
|
|
Py_INCREF(obj);
|
|
return obj;
|
|
}
|
|
|
|
static inline PyObject* _Py_XNewRef(PyObject *obj)
|
|
{
|
|
Py_XINCREF(obj);
|
|
return obj;
|
|
}
|
|
|
|
// Py_NewRef() and Py_XNewRef() are exported as functions for the stable ABI.
|
|
// Names overridden with macros by static inline functions for best
|
|
// performances.
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define Py_NewRef(obj) _Py_NewRef(_PyObject_CAST(obj))
|
|
# define Py_XNewRef(obj) _Py_XNewRef(_PyObject_CAST(obj))
|
|
#else
|
|
# define Py_NewRef(obj) _Py_NewRef(obj)
|
|
# define Py_XNewRef(obj) _Py_XNewRef(obj)
|
|
#endif
|
|
|
|
|
|
/*
|
|
_Py_NoneStruct is an object of undefined type which can be used in contexts
|
|
where NULL (nil) is not suitable (since NULL often means 'error').
|
|
*/
|
|
PyAPI_DATA(PyObject) _Py_NoneStruct; /* Don't use this directly */
|
|
#define Py_None (&_Py_NoneStruct)
|
|
|
|
// Test if an object is the None singleton, the same as "x is None" in Python.
|
|
PyAPI_FUNC(int) Py_IsNone(PyObject *x);
|
|
#define Py_IsNone(x) Py_Is((x), Py_None)
|
|
|
|
/* Macro for returning Py_None from a function */
|
|
#define Py_RETURN_NONE return Py_None
|
|
|
|
/*
|
|
Py_NotImplemented is a singleton used to signal that an operation is
|
|
not implemented for a given type combination.
|
|
*/
|
|
PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
|
|
#define Py_NotImplemented (&_Py_NotImplementedStruct)
|
|
|
|
/* Macro for returning Py_NotImplemented from a function */
|
|
#define Py_RETURN_NOTIMPLEMENTED return Py_NotImplemented
|
|
|
|
/* Rich comparison opcodes */
|
|
#define Py_LT 0
|
|
#define Py_LE 1
|
|
#define Py_EQ 2
|
|
#define Py_NE 3
|
|
#define Py_GT 4
|
|
#define Py_GE 5
|
|
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030A0000
|
|
/* Result of calling PyIter_Send */
|
|
typedef enum {
|
|
PYGEN_RETURN = 0,
|
|
PYGEN_ERROR = -1,
|
|
PYGEN_NEXT = 1,
|
|
} PySendResult;
|
|
#endif
|
|
|
|
/*
|
|
* Macro for implementing rich comparisons
|
|
*
|
|
* Needs to be a macro because any C-comparable type can be used.
|
|
*/
|
|
#define Py_RETURN_RICHCOMPARE(val1, val2, op) \
|
|
do { \
|
|
switch (op) { \
|
|
case Py_EQ: if ((val1) == (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_NE: if ((val1) != (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_LT: if ((val1) < (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_GT: if ((val1) > (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_LE: if ((val1) <= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_GE: if ((val1) >= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
default: \
|
|
Py_UNREACHABLE(); \
|
|
} \
|
|
} while (0)
|
|
|
|
|
|
/*
|
|
More conventions
|
|
================
|
|
|
|
Argument Checking
|
|
-----------------
|
|
|
|
Functions that take objects as arguments normally don't check for nil
|
|
arguments, but they do check the type of the argument, and return an
|
|
error if the function doesn't apply to the type.
|
|
|
|
Failure Modes
|
|
-------------
|
|
|
|
Functions may fail for a variety of reasons, including running out of
|
|
memory. This is communicated to the caller in two ways: an error string
|
|
is set (see errors.h), and the function result differs: functions that
|
|
normally return a pointer return NULL for failure, functions returning
|
|
an integer return -1 (which could be a legal return value too!), and
|
|
other functions return 0 for success and -1 for failure.
|
|
Callers should always check for errors before using the result. If
|
|
an error was set, the caller must either explicitly clear it, or pass
|
|
the error on to its caller.
|
|
|
|
Reference Counts
|
|
----------------
|
|
|
|
It takes a while to get used to the proper usage of reference counts.
|
|
|
|
Functions that create an object set the reference count to 1; such new
|
|
objects must be stored somewhere or destroyed again with Py_DECREF().
|
|
Some functions that 'store' objects, such as PyTuple_SetItem() and
|
|
PyList_SetItem(),
|
|
don't increment the reference count of the object, since the most
|
|
frequent use is to store a fresh object. Functions that 'retrieve'
|
|
objects, such as PyTuple_GetItem() and PyDict_GetItemString(), also
|
|
don't increment
|
|
the reference count, since most frequently the object is only looked at
|
|
quickly. Thus, to retrieve an object and store it again, the caller
|
|
must call Py_INCREF() explicitly.
|
|
|
|
NOTE: functions that 'consume' a reference count, like
|
|
PyList_SetItem(), consume the reference even if the object wasn't
|
|
successfully stored, to simplify error handling.
|
|
|
|
It seems attractive to make other functions that take an object as
|
|
argument consume a reference count; however, this may quickly get
|
|
confusing (even the current practice is already confusing). Consider
|
|
it carefully, it may save lots of calls to Py_INCREF() and Py_DECREF() at
|
|
times.
|
|
*/
|
|
|
|
#ifndef Py_LIMITED_API
|
|
# define Py_CPYTHON_OBJECT_H
|
|
# include "cpython/object.h"
|
|
# undef Py_CPYTHON_OBJECT_H
|
|
#endif
|
|
|
|
|
|
static inline int
|
|
PyType_HasFeature(PyTypeObject *type, unsigned long feature)
|
|
{
|
|
unsigned long flags;
|
|
#ifdef Py_LIMITED_API
|
|
// PyTypeObject is opaque in the limited C API
|
|
flags = PyType_GetFlags(type);
|
|
#else
|
|
flags = type->tp_flags;
|
|
#endif
|
|
return ((flags & feature) != 0);
|
|
}
|
|
|
|
#define PyType_FastSubclass(type, flag) PyType_HasFeature((type), (flag))
|
|
|
|
static inline int PyType_Check(PyObject *op) {
|
|
return PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_TYPE_SUBCLASS);
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define PyType_Check(op) PyType_Check(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
#define _PyType_CAST(op) \
|
|
(assert(PyType_Check(op)), _Py_CAST(PyTypeObject*, (op)))
|
|
|
|
static inline int PyType_CheckExact(PyObject *op) {
|
|
return Py_IS_TYPE(op, &PyType_Type);
|
|
}
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
|
|
# define PyType_CheckExact(op) PyType_CheckExact(_PyObject_CAST(op))
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif // !Py_OBJECT_H
|