mirror of
https://github.com/python/cpython.git
synced 2025-11-04 11:49:12 +00:00
e421106b9e
Include/*.h should be the "portable Python API", whereas Include/cpython/*.h should be the "CPython API": CPython implementation details. Changes: * Create Include/cpython/ subdirectory * "make install" now creates $prefix/include/cpython and copy Include/cpython/* to $prefix/include/cpython * Create Include/cpython/objimpl.h: move objimpl.h code surrounded by "#ifndef Py_LIMITED_API" to cpython/objimpl.h. * objimpl.h now includes cpython/objimpl.h * Windows installer (MSI) now also install Include/ subdirectories: Include/cpython/ and Include/internal/.
281 lines
10 KiB
C
281 lines
10 KiB
C
/* The PyObject_ memory family: high-level object memory interfaces.
|
|
See pymem.h for the low-level PyMem_ family.
|
|
*/
|
|
|
|
#ifndef Py_OBJIMPL_H
|
|
#define Py_OBJIMPL_H
|
|
|
|
#include "pymem.h"
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/* BEWARE:
|
|
|
|
Each interface exports both functions and macros. Extension modules should
|
|
use the functions, to ensure binary compatibility across Python versions.
|
|
Because the Python implementation is free to change internal details, and
|
|
the macros may (or may not) expose details for speed, if you do use the
|
|
macros you must recompile your extensions with each Python release.
|
|
|
|
Never mix calls to PyObject_ memory functions with calls to the platform
|
|
malloc/realloc/ calloc/free, or with calls to PyMem_.
|
|
*/
|
|
|
|
/*
|
|
Functions and macros for modules that implement new object types.
|
|
|
|
- PyObject_New(type, typeobj) allocates memory for a new object of the given
|
|
type, and initializes part of it. 'type' must be the C structure type used
|
|
to represent the object, and 'typeobj' the address of the corresponding
|
|
type object. Reference count and type pointer are filled in; the rest of
|
|
the bytes of the object are *undefined*! The resulting expression type is
|
|
'type *'. The size of the object is determined by the tp_basicsize field
|
|
of the type object.
|
|
|
|
- PyObject_NewVar(type, typeobj, n) is similar but allocates a variable-size
|
|
object with room for n items. In addition to the refcount and type pointer
|
|
fields, this also fills in the ob_size field.
|
|
|
|
- PyObject_Del(op) releases the memory allocated for an object. It does not
|
|
run a destructor -- it only frees the memory. PyObject_Free is identical.
|
|
|
|
- PyObject_Init(op, typeobj) and PyObject_InitVar(op, typeobj, n) don't
|
|
allocate memory. Instead of a 'type' parameter, they take a pointer to a
|
|
new object (allocated by an arbitrary allocator), and initialize its object
|
|
header fields.
|
|
|
|
Note that objects created with PyObject_{New, NewVar} are allocated using the
|
|
specialized Python allocator (implemented in obmalloc.c), if WITH_PYMALLOC is
|
|
enabled. In addition, a special debugging allocator is used if PYMALLOC_DEBUG
|
|
is also #defined.
|
|
|
|
In case a specific form of memory management is needed (for example, if you
|
|
must use the platform malloc heap(s), or shared memory, or C++ local storage or
|
|
operator new), you must first allocate the object with your custom allocator,
|
|
then pass its pointer to PyObject_{Init, InitVar} for filling in its Python-
|
|
specific fields: reference count, type pointer, possibly others. You should
|
|
be aware that Python has no control over these objects because they don't
|
|
cooperate with the Python memory manager. Such objects may not be eligible
|
|
for automatic garbage collection and you have to make sure that they are
|
|
released accordingly whenever their destructor gets called (cf. the specific
|
|
form of memory management you're using).
|
|
|
|
Unless you have specific memory management requirements, use
|
|
PyObject_{New, NewVar, Del}.
|
|
*/
|
|
|
|
/*
|
|
* Raw object memory interface
|
|
* ===========================
|
|
*/
|
|
|
|
/* Functions to call the same malloc/realloc/free as used by Python's
|
|
object allocator. If WITH_PYMALLOC is enabled, these may differ from
|
|
the platform malloc/realloc/free. The Python object allocator is
|
|
designed for fast, cache-conscious allocation of many "small" objects,
|
|
and with low hidden memory overhead.
|
|
|
|
PyObject_Malloc(0) returns a unique non-NULL pointer if possible.
|
|
|
|
PyObject_Realloc(NULL, n) acts like PyObject_Malloc(n).
|
|
PyObject_Realloc(p != NULL, 0) does not return NULL, or free the memory
|
|
at p.
|
|
|
|
Returned pointers must be checked for NULL explicitly; no action is
|
|
performed on failure other than to return NULL (no warning it printed, no
|
|
exception is set, etc).
|
|
|
|
For allocating objects, use PyObject_{New, NewVar} instead whenever
|
|
possible. The PyObject_{Malloc, Realloc, Free} family is exposed
|
|
so that you can exploit Python's small-block allocator for non-object
|
|
uses. If you must use these routines to allocate object memory, make sure
|
|
the object gets initialized via PyObject_{Init, InitVar} after obtaining
|
|
the raw memory.
|
|
*/
|
|
PyAPI_FUNC(void *) PyObject_Malloc(size_t size);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03050000
|
|
PyAPI_FUNC(void *) PyObject_Calloc(size_t nelem, size_t elsize);
|
|
#endif
|
|
PyAPI_FUNC(void *) PyObject_Realloc(void *ptr, size_t new_size);
|
|
PyAPI_FUNC(void) PyObject_Free(void *ptr);
|
|
|
|
|
|
/* Macros */
|
|
#define PyObject_MALLOC PyObject_Malloc
|
|
#define PyObject_REALLOC PyObject_Realloc
|
|
#define PyObject_FREE PyObject_Free
|
|
#define PyObject_Del PyObject_Free
|
|
#define PyObject_DEL PyObject_Free
|
|
|
|
|
|
/*
|
|
* Generic object allocator interface
|
|
* ==================================
|
|
*/
|
|
|
|
/* Functions */
|
|
PyAPI_FUNC(PyObject *) PyObject_Init(PyObject *, PyTypeObject *);
|
|
PyAPI_FUNC(PyVarObject *) PyObject_InitVar(PyVarObject *,
|
|
PyTypeObject *, Py_ssize_t);
|
|
PyAPI_FUNC(PyObject *) _PyObject_New(PyTypeObject *);
|
|
PyAPI_FUNC(PyVarObject *) _PyObject_NewVar(PyTypeObject *, Py_ssize_t);
|
|
|
|
#define PyObject_New(type, typeobj) \
|
|
( (type *) _PyObject_New(typeobj) )
|
|
#define PyObject_NewVar(type, typeobj, n) \
|
|
( (type *) _PyObject_NewVar((typeobj), (n)) )
|
|
|
|
/* Inline functions trading binary compatibility for speed:
|
|
PyObject_INIT() is the fast version of PyObject_Init(), and
|
|
PyObject_INIT_VAR() is the fast version of PyObject_InitVar.
|
|
See also pymem.h.
|
|
|
|
These inline functions expect non-NULL object pointers. */
|
|
static inline PyObject*
|
|
_PyObject_INIT(PyObject *op, PyTypeObject *typeobj)
|
|
{
|
|
assert(op != NULL);
|
|
Py_TYPE(op) = typeobj;
|
|
_Py_NewReference(op);
|
|
return op;
|
|
}
|
|
|
|
#define PyObject_INIT(op, typeobj) \
|
|
_PyObject_INIT(_PyObject_CAST(op), (typeobj))
|
|
|
|
static inline PyVarObject*
|
|
_PyObject_INIT_VAR(PyVarObject *op, PyTypeObject *typeobj, Py_ssize_t size)
|
|
{
|
|
assert(op != NULL);
|
|
Py_SIZE(op) = size;
|
|
PyObject_INIT((PyObject *)op, typeobj);
|
|
return op;
|
|
}
|
|
|
|
#define PyObject_INIT_VAR(op, typeobj, size) \
|
|
_PyObject_INIT_VAR(_PyVarObject_CAST(op), (typeobj), (size))
|
|
|
|
#define _PyObject_SIZE(typeobj) ( (typeobj)->tp_basicsize )
|
|
|
|
/* _PyObject_VAR_SIZE returns the number of bytes (as size_t) allocated for a
|
|
vrbl-size object with nitems items, exclusive of gc overhead (if any). The
|
|
value is rounded up to the closest multiple of sizeof(void *), in order to
|
|
ensure that pointer fields at the end of the object are correctly aligned
|
|
for the platform (this is of special importance for subclasses of, e.g.,
|
|
str or int, so that pointers can be stored after the embedded data).
|
|
|
|
Note that there's no memory wastage in doing this, as malloc has to
|
|
return (at worst) pointer-aligned memory anyway.
|
|
*/
|
|
#if ((SIZEOF_VOID_P - 1) & SIZEOF_VOID_P) != 0
|
|
# error "_PyObject_VAR_SIZE requires SIZEOF_VOID_P be a power of 2"
|
|
#endif
|
|
|
|
#define _PyObject_VAR_SIZE(typeobj, nitems) \
|
|
_Py_SIZE_ROUND_UP((typeobj)->tp_basicsize + \
|
|
(nitems)*(typeobj)->tp_itemsize, \
|
|
SIZEOF_VOID_P)
|
|
|
|
#define PyObject_NEW(type, typeobj) \
|
|
( (type *) PyObject_Init( \
|
|
(PyObject *) PyObject_MALLOC( _PyObject_SIZE(typeobj) ), (typeobj)) )
|
|
|
|
#define PyObject_NEW_VAR(type, typeobj, n) \
|
|
( (type *) PyObject_InitVar( \
|
|
(PyVarObject *) PyObject_MALLOC(_PyObject_VAR_SIZE((typeobj),(n)) ),\
|
|
(typeobj), (n)) )
|
|
|
|
/* This example code implements an object constructor with a custom
|
|
allocator, where PyObject_New is inlined, and shows the important
|
|
distinction between two steps (at least):
|
|
1) the actual allocation of the object storage;
|
|
2) the initialization of the Python specific fields
|
|
in this storage with PyObject_{Init, InitVar}.
|
|
|
|
PyObject *
|
|
YourObject_New(...)
|
|
{
|
|
PyObject *op;
|
|
|
|
op = (PyObject *) Your_Allocator(_PyObject_SIZE(YourTypeStruct));
|
|
if (op == NULL)
|
|
return PyErr_NoMemory();
|
|
|
|
PyObject_Init(op, &YourTypeStruct);
|
|
|
|
op->ob_field = value;
|
|
...
|
|
return op;
|
|
}
|
|
|
|
Note that in C++, the use of the new operator usually implies that
|
|
the 1st step is performed automatically for you, so in a C++ class
|
|
constructor you would start directly with PyObject_Init/InitVar
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
* Garbage Collection Support
|
|
* ==========================
|
|
*/
|
|
|
|
/* C equivalent of gc.collect() which ignores the state of gc.enabled. */
|
|
PyAPI_FUNC(Py_ssize_t) PyGC_Collect(void);
|
|
|
|
/* Test if a type has a GC head */
|
|
#define PyType_IS_GC(t) PyType_HasFeature((t), Py_TPFLAGS_HAVE_GC)
|
|
|
|
PyAPI_FUNC(PyVarObject *) _PyObject_GC_Resize(PyVarObject *, Py_ssize_t);
|
|
#define PyObject_GC_Resize(type, op, n) \
|
|
( (type *) _PyObject_GC_Resize(_PyVarObject_CAST(op), (n)) )
|
|
|
|
|
|
|
|
PyAPI_FUNC(PyObject *) _PyObject_GC_New(PyTypeObject *);
|
|
PyAPI_FUNC(PyVarObject *) _PyObject_GC_NewVar(PyTypeObject *, Py_ssize_t);
|
|
|
|
/* Tell the GC to track this object.
|
|
*
|
|
* See also private _PyObject_GC_TRACK() macro. */
|
|
PyAPI_FUNC(void) PyObject_GC_Track(void *);
|
|
|
|
/* Tell the GC to stop tracking this object.
|
|
*
|
|
* See also private _PyObject_GC_UNTRACK() macro. */
|
|
PyAPI_FUNC(void) PyObject_GC_UnTrack(void *);
|
|
|
|
PyAPI_FUNC(void) PyObject_GC_Del(void *);
|
|
|
|
#define PyObject_GC_New(type, typeobj) \
|
|
( (type *) _PyObject_GC_New(typeobj) )
|
|
#define PyObject_GC_NewVar(type, typeobj, n) \
|
|
( (type *) _PyObject_GC_NewVar((typeobj), (n)) )
|
|
|
|
|
|
/* Utility macro to help write tp_traverse functions.
|
|
* To use this macro, the tp_traverse function must name its arguments
|
|
* "visit" and "arg". This is intended to keep tp_traverse functions
|
|
* looking as much alike as possible.
|
|
*/
|
|
#define Py_VISIT(op) \
|
|
do { \
|
|
if (op) { \
|
|
int vret = visit(_PyObject_CAST(op), arg); \
|
|
if (vret) \
|
|
return vret; \
|
|
} \
|
|
} while (0)
|
|
|
|
#ifndef Py_LIMITED_API
|
|
# define Py_CPYTHON_OBJIMPL_H
|
|
# include "cpython/objimpl.h"
|
|
# undef Py_CPYTHON_OBJIMPL_H
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_OBJIMPL_H */
|