diff options
| author | thegeorg <[email protected]> | 2024-02-19 02:38:52 +0300 |
|---|---|---|
| committer | thegeorg <[email protected]> | 2024-02-19 02:50:43 +0300 |
| commit | d96fa07134c06472bfee6718b5cfd1679196fc99 (patch) | |
| tree | 31ec344fa9d3ff8dc038692516b6438dfbdb8a2d /contrib/tools/python3/Include/cpython/objimpl.h | |
| parent | 452cf9e068aef7110e35e654c5d47eb80111ef89 (diff) | |
Sync contrib/tools/python3 layout with upstream
* Move src/ subdir contents to the top of the layout
* Rename self-written lib -> lib2 to avoid CaseFolding warning from the VCS
* Regenerate contrib/libs/python proxy-headers accordingly
4ccc62ac1511abcf0fed14ccade38e984e088f1e
Diffstat (limited to 'contrib/tools/python3/Include/cpython/objimpl.h')
| -rw-r--r-- | contrib/tools/python3/Include/cpython/objimpl.h | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/contrib/tools/python3/Include/cpython/objimpl.h b/contrib/tools/python3/Include/cpython/objimpl.h new file mode 100644 index 00000000000..5a8cdd57c78 --- /dev/null +++ b/contrib/tools/python3/Include/cpython/objimpl.h @@ -0,0 +1,95 @@ +#ifndef Py_CPYTHON_OBJIMPL_H +# error "this header file must not be included directly" +#endif + +static inline size_t _PyObject_SIZE(PyTypeObject *type) { + return _Py_STATIC_CAST(size_t, type->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 + +static inline size_t _PyObject_VAR_SIZE(PyTypeObject *type, Py_ssize_t nitems) { + size_t size = _Py_STATIC_CAST(size_t, type->tp_basicsize); + size += _Py_STATIC_CAST(size_t, nitems) * _Py_STATIC_CAST(size_t, type->tp_itemsize); + return _Py_SIZE_ROUND_UP(size, SIZEOF_VOID_P); +} + + +/* 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. */ + + +typedef struct { + /* user context passed as the first argument to the 2 functions */ + void *ctx; + + /* allocate an arena of size bytes */ + void* (*alloc) (void *ctx, size_t size); + + /* free an arena */ + void (*free) (void *ctx, void *ptr, size_t size); +} PyObjectArenaAllocator; + +/* Get the arena allocator. */ +PyAPI_FUNC(void) PyObject_GetArenaAllocator(PyObjectArenaAllocator *allocator); + +/* Set the arena allocator. */ +PyAPI_FUNC(void) PyObject_SetArenaAllocator(PyObjectArenaAllocator *allocator); + + +/* Test if an object implements the garbage collector protocol */ +PyAPI_FUNC(int) PyObject_IS_GC(PyObject *obj); + + +/* Code built with Py_BUILD_CORE must include pycore_gc.h instead which + defines a different _PyGC_FINALIZED() macro. */ +#ifndef Py_BUILD_CORE + // Kept for backward compatibility with Python 3.8 +# define _PyGC_FINALIZED(o) PyObject_GC_IsFinalized(o) +#endif + + +// Test if a type supports weak references +PyAPI_FUNC(int) PyType_SUPPORTS_WEAKREFS(PyTypeObject *type); + +PyAPI_FUNC(PyObject **) PyObject_GET_WEAKREFS_LISTPTR(PyObject *op); + +PyAPI_FUNC(PyObject *) PyUnstable_Object_GC_NewWithExtraData(PyTypeObject *, + size_t); |
