bpo-40170: Add _PyObject_CheckBuffer() internal function

Include/internal/pycore_object.h

@@ -111,6 +111,14 @@ _PyObject_IS_GC(PyObject *obj)
                 || Py_TYPE(obj)->tp_is_gc(obj)));
 }
 
+// Fast inlined version of PyObject_CheckBuffer()
+static inline int
+_PyObject_CheckBuffer(PyObject *obj)
+{
+    PyBufferProcs *tp_as_buffer = Py_TYPE(obj)->tp_as_buffer;
+    return (tp_as_buffer != NULL && tp_as_buffer->bf_getbuffer != NULL);
+}
+
 // Fast inlined version of PyType_IS_GC()
 #define _PyType_IS_GC(t) _PyType_HasFeature((t), Py_TPFLAGS_HAVE_GC)
 

Objects/abstract.c

@@ -3,6 +3,7 @@
 #include "Python.h"
 #include "pycore_abstract.h"      // _PyIndex_Check()
 #include "pycore_ceval.h"         // _Py_EnterRecursiveCall()
+#include "pycore_object.h"
 #include "pycore_pyerrors.h"
 #include "pycore_pystate.h"       // _PyThreadState_GET()
 #include <ctype.h>
@@ -283,8 +284,7 @@ PyObject_DelItemString(PyObject *o, const char *key)
 int
 PyObject_CheckBuffer(PyObject *obj)
 {
-    PyBufferProcs *tp_as_buffer = Py_TYPE(obj)->tp_as_buffer;
-    return (tp_as_buffer != NULL && tp_as_buffer->bf_getbuffer != NULL);
+    return _PyObject_CheckBuffer(obj);
 }
 
 
@@ -615,8 +615,8 @@ int PyObject_CopyData(PyObject *dest, PyObject *src)
     Py_ssize_t *indices, elements;
     char *dptr, *sptr;
 
-    if (!PyObject_CheckBuffer(dest) ||
-        !PyObject_CheckBuffer(src)) {
+    if (!_PyObject_CheckBuffer(dest) ||
+        !_PyObject_CheckBuffer(src)) {
         PyErr_SetString(PyExc_TypeError,
                         "both destination and source must be "\
                         "bytes-like objects");

Objects/bytearrayobject.c

@@ -829,7 +829,7 @@ bytearray_init(PyByteArrayObject *self, PyObject *args, PyObject *kwds)
     }
 
     /* Use the buffer API */
-    if (PyObject_CheckBuffer(arg)) {
+    if (_PyObject_CheckBuffer(arg)) {
         Py_ssize_t size;
         Py_buffer view;
         if (PyObject_GetBuffer(arg, &view, PyBUF_FULL_RO) < 0)
@@ -1614,7 +1614,7 @@ bytearray_extend(PyByteArrayObject *self, PyObject *iterable_of_ints)
     char *buf;
 
     /* bytearray_setslice code only accepts something supporting PEP 3118. */
-    if (PyObject_CheckBuffer(iterable_of_ints)) {
+    if (_PyObject_CheckBuffer(iterable_of_ints)) {
         if (bytearray_setslice(self, Py_SIZE(self), Py_SIZE(self), iterable_of_ints) == -1)
             return NULL;
 

Objects/bytes_methods.c

@@ -2,6 +2,7 @@
 #include "Python.h"
 #include "pycore_abstract.h"   // _PyIndex_Check()
 #include "pycore_bytes_methods.h"
+#include "pycore_object.h"
 
 PyDoc_STRVAR_shared(_Py_isspace__doc__,
 "B.isspace() -> bool\n\
@@ -462,7 +463,7 @@ parse_args_finds_byte(const char *function_name, PyObject *args,
                                    start, end))
         return 0;
 
-    if (PyObject_CheckBuffer(tmp_subobj)) {
+    if (_PyObject_CheckBuffer(tmp_subobj)) {
         *subobj = tmp_subobj;
         return 1;
     }

Objects/bytesobject.c

@@ -561,7 +561,7 @@ format_obj(PyObject *v, const char **pbuf, Py_ssize_t *plen)
         return result;
     }
     /* does it support buffer protocol? */
-    if (PyObject_CheckBuffer(v)) {
+    if (_PyObject_CheckBuffer(v)) {
         /* maybe we can avoid making a copy of the buffer object here? */
         result = _PyBytes_FromBuffer(v);
         if (result == NULL)
@@ -2740,7 +2740,7 @@ PyBytes_FromObject(PyObject *x)
     }
 
     /* Use the modern buffer interface */
-    if (PyObject_CheckBuffer(x))
+    if (_PyObject_CheckBuffer(x))
         return _PyBytes_FromBuffer(x);
 
     if (PyList_CheckExact(x))

Objects/memoryobject.c

@@ -800,7 +800,7 @@ PyMemoryView_FromObject(PyObject *v)
         CHECK_RELEASED(mv);
         return mbuf_add_view(mv->mbuf, &mv->view);
     }
-    else if (PyObject_CheckBuffer(v)) {
+    else if (_PyObject_CheckBuffer(v)) {
         PyObject *ret;
         mbuf = (_PyManagedBufferObject *)_PyManagedBuffer_FromObject(v);
         if (mbuf == NULL)

Objects/unicodeobject.c

@@ -3936,7 +3936,7 @@ PyUnicode_FSDecoder(PyObject* arg, void* addr)
         return 1;
     }
 
-    is_buffer = PyObject_CheckBuffer(arg);
+    is_buffer = _PyObject_CheckBuffer(arg);
     if (!is_buffer) {
         path = PyOS_FSPath(arg);
         if (path == NULL) {

PC/winreg.c

@@ -14,6 +14,7 @@
 
 #define PY_SSIZE_T_CLEAN
 #include "Python.h"
+#include "pycore_object.h"
 #include "structmember.h"         // PyMemberDef
 #include <windows.h>
 
@@ -689,7 +690,7 @@ Py2Reg(PyObject *value, DWORD typ, BYTE **retDataBuf, DWORD *retDataSize)
             else {
                 Py_buffer view;
 
-                if (!PyObject_CheckBuffer(value)) {
+                if (!_PyObject_CheckBuffer(value)) {
                     PyErr_Format(PyExc_TypeError,
                         "Objects of type '%s' can not "
                         "be used as binary registry values",

Python/marshal.c

@@ -9,6 +9,7 @@
 #define PY_SSIZE_T_CLEAN
 
 #include "Python.h"
+#include "pycore_object.h"
 #include "longintrepr.h"
 #include "code.h"
 #include "marshal.h"
@@ -526,7 +527,7 @@ w_complex_object(PyObject *v, char flag, WFILE *p)
         w_long(co->co_firstlineno, p);
         w_object(co->co_lnotab, p);
     }
-    else if (PyObject_CheckBuffer(v)) {
+    else if (_PyObject_CheckBuffer(v)) {
         /* Write unknown bytes-like objects as a bytes object */
         Py_buffer view;
         if (PyObject_GetBuffer(v, &view, PyBUF_SIMPLE) != 0) {