use memoryview from CPython

Author: timfel

graalpython/com.oracle.graal.python.cext/include/Python.h

@@ -103,6 +103,7 @@
 #include "pydebug.h"
 #include "code.h"
 #include "pyfpe.h"
+#include "memoryobject.h"
 
 // our impls
 #ifdef Py_True

graalpython/com.oracle.graal.python.cext/include/memoryobject.h

@@ -0,0 +1,73 @@
+/* Memory view object. In Python this is available as "memoryview". */
+
+#ifndef Py_MEMORYOBJECT_H
+#define Py_MEMORYOBJECT_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef Py_LIMITED_API
+PyAPI_DATA(PyTypeObject) _PyManagedBuffer_Type;
+#endif
+PyAPI_DATA(PyTypeObject) PyMemoryView_Type;
+
+#define PyMemoryView_Check(op) (Py_TYPE(op) == &PyMemoryView_Type)
+
+#ifndef Py_LIMITED_API
+/* Get a pointer to the memoryview's private copy of the exporter's buffer. */
+#define PyMemoryView_GET_BUFFER(op) (&((PyMemoryViewObject *)(op))->view)
+/* Get a pointer to the exporting object (this may be NULL!). */
+#define PyMemoryView_GET_BASE(op) (((PyMemoryViewObject *)(op))->view.obj)
+#endif
+
+PyAPI_FUNC(PyObject *) PyMemoryView_FromObject(PyObject *base);
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
+PyAPI_FUNC(PyObject *) PyMemoryView_FromMemory(char *mem, Py_ssize_t size,
+                                               int flags);
+#endif
+#ifndef Py_LIMITED_API
+PyAPI_FUNC(PyObject *) PyMemoryView_FromBuffer(Py_buffer *info);
+#endif
+PyAPI_FUNC(PyObject *) PyMemoryView_GetContiguous(PyObject *base,
+                                                  int buffertype,
+                                                  char order);
+
+
+/* The structs are declared here so that macros can work, but they shouldn't
+   be considered public. Don't access their fields directly, use the macros
+   and functions instead! */
+#ifndef Py_LIMITED_API
+#define _Py_MANAGED_BUFFER_RELEASED    0x001  /* access to exporter blocked */
+#define _Py_MhANAGED_BUFFER_FREE_FORMAT 0x002  /* free format */
+typedef struct {
+    PyObject_HEAD
+    int flags;          /* state flags */
+    Py_ssize_t exports; /* number of direct memoryview exports */
+    Py_buffer master; /* snapshot buffer obtained from the original exporter */
+} _PyManagedBufferObject;
+
+
+/* memoryview state flags */
+#define _Py_MEMORYVIEW_RELEASED    0x001  /* access to master buffer blocked */
+#define _Py_MEMORYVIEW_C           0x002  /* C-contiguous layout */
+#define _Py_MEMORYVIEW_FORTRAN     0x004  /* Fortran contiguous layout */
+#define _Py_MEMORYVIEW_SCALAR      0x008  /* scalar: ndim = 0 */
+#define _Py_MEMORYVIEW_PIL         0x010  /* PIL-style layout */
+
+typedef struct {
+    PyObject_VAR_HEAD
+    _PyManagedBufferObject *mbuf; /* managed buffer */
+    Py_hash_t hash;               /* hash value for read-only views */
+    int flags;                    /* state flags */
+    Py_ssize_t exports;           /* number of buffer re-exports */
+    Py_buffer view;               /* private copy of the exporter's view */
+    PyObject *weakreflist;
+    Py_ssize_t ob_array[1];       /* shape, strides, suboffsets */
+} PyMemoryViewObject;
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_MEMORYOBJECT_H */
+