summaryrefslogtreecommitdiffstats
path: root/contrib/tools/python3/Include/cpython/objimpl.h
diff options
context:
space:
mode:
authorthegeorg <[email protected]>2024-02-19 02:38:52 +0300
committerthegeorg <[email protected]>2024-02-19 02:50:43 +0300
commitd96fa07134c06472bfee6718b5cfd1679196fc99 (patch)
tree31ec344fa9d3ff8dc038692516b6438dfbdb8a2d /contrib/tools/python3/Include/cpython/objimpl.h
parent452cf9e068aef7110e35e654c5d47eb80111ef89 (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.h95
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);