1 /* Memory view object. In Python this is available as "memoryview". */ 2 3 #ifndef Py_MEMORYOBJECT_H 4 #define Py_MEMORYOBJECT_H 5 #ifdef __cplusplus 6 extern "C" { 7 #endif 8 9 PyAPI_DATA(PyTypeObject) PyMemoryView_Type; 10 11 #define PyMemoryView_Check(op) (Py_TYPE(op) == &PyMemoryView_Type) 12 13 /* Get a pointer to the underlying Py_buffer of a memoryview object. */ 14 #define PyMemoryView_GET_BUFFER(op) (&((PyMemoryViewObject *)(op))->view) 15 /* Get a pointer to the PyObject from which originates a memoryview object. */ 16 #define PyMemoryView_GET_BASE(op) (((PyMemoryViewObject *)(op))->view.obj) 17 18 19 PyAPI_FUNC(PyObject *) PyMemoryView_GetContiguous(PyObject *base, 20 int buffertype, 21 char fort); 22 23 /* Return a contiguous chunk of memory representing the buffer 24 from an object in a memory view object. If a copy is made then the 25 base object for the memory view will be a *new* bytes object. 26 27 Otherwise, the base-object will be the object itself and no 28 data-copying will be done. 29 30 The buffertype argument can be PyBUF_READ, PyBUF_WRITE, 31 PyBUF_SHADOW to determine whether the returned buffer 32 should be READONLY, WRITABLE, or set to update the 33 original buffer if a copy must be made. If buffertype is 34 PyBUF_WRITE and the buffer is not contiguous an error will 35 be raised. In this circumstance, the user can use 36 PyBUF_SHADOW to ensure that a a writable temporary 37 contiguous buffer is returned. The contents of this 38 contiguous buffer will be copied back into the original 39 object after the memoryview object is deleted as long as 40 the original object is writable and allows setting an 41 exclusive write lock. If this is not allowed by the 42 original object, then a BufferError is raised. 43 44 If the object is multi-dimensional and if fortran is 'F', 45 the first dimension of the underlying array will vary the 46 fastest in the buffer. If fortran is 'C', then the last 47 dimension will vary the fastest (C-style contiguous). If 48 fortran is 'A', then it does not matter and you will get 49 whatever the object decides is more efficient. 50 51 A new reference is returned that must be DECREF'd when finished. 52 */ 53 54 PyAPI_FUNC(PyObject *) PyMemoryView_FromObject(PyObject *base); 55 56 PyAPI_FUNC(PyObject *) PyMemoryView_FromBuffer(Py_buffer *info); 57 /* create new if bufptr is NULL 58 will be a new bytesobject in base */ 59 60 61 /* The struct is declared here so that macros can work, but it shouldn't 62 be considered public. Don't access those fields directly, use the macros 63 and functions instead! */ 64 typedef struct { 65 PyObject_HEAD 66 PyObject *base; 67 Py_buffer view; 68 } PyMemoryViewObject; 69 70 71 #ifdef __cplusplus 72 } 73 #endif 74 #endif /* !Py_MEMORYOBJECT_H */ 75
