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aeb6ceead7
unused undocumented value PyBUF_SHADOW, and strangely-looking code in PyMemoryView_GetContiguous.
74 lines
2.7 KiB
C
74 lines
2.7 KiB
C
/* Memory view object. In Python this is available as "memoryview". */
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#ifndef Py_MEMORYOBJECT_H
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#define Py_MEMORYOBJECT_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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PyAPI_DATA(PyTypeObject) PyMemoryView_Type;
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#define PyMemoryView_Check(op) (Py_TYPE(op) == &PyMemoryView_Type)
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/* Get a pointer to the underlying Py_buffer of a memoryview object. */
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#define PyMemoryView_GET_BUFFER(op) (&((PyMemoryViewObject *)(op))->view)
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/* Get a pointer to the PyObject from which originates a memoryview object. */
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#define PyMemoryView_GET_BASE(op) (((PyMemoryViewObject *)(op))->view.obj)
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PyAPI_FUNC(PyObject *) PyMemoryView_GetContiguous(PyObject *base,
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int buffertype,
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char fort);
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/* Return a contiguous chunk of memory representing the buffer
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from an object in a memory view object. If a copy is made then the
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base object for the memory view will be a *new* bytes object.
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Otherwise, the base-object will be the object itself and no
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data-copying will be done.
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The buffertype argument can be PyBUF_READ, PyBUF_WRITE,
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PyBUF_SHADOW to determine whether the returned buffer
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should be READONLY, WRITABLE, or set to update the
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original buffer if a copy must be made. If buffertype is
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PyBUF_WRITE and the buffer is not contiguous an error will
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be raised. In this circumstance, the user can use
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PyBUF_SHADOW to ensure that a a writable temporary
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contiguous buffer is returned. The contents of this
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contiguous buffer will be copied back into the original
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object after the memoryview object is deleted as long as
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the original object is writable and allows setting an
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exclusive write lock. If this is not allowed by the
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original object, then a BufferError is raised.
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If the object is multi-dimensional and if fortran is 'F',
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the first dimension of the underlying array will vary the
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fastest in the buffer. If fortran is 'C', then the last
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dimension will vary the fastest (C-style contiguous). If
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fortran is 'A', then it does not matter and you will get
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whatever the object decides is more efficient.
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A new reference is returned that must be DECREF'd when finished.
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*/
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PyAPI_FUNC(PyObject *) PyMemoryView_FromObject(PyObject *base);
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PyAPI_FUNC(PyObject *) PyMemoryView_FromBuffer(Py_buffer *info);
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/* create new if bufptr is NULL
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will be a new bytesobject in base */
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/* The struct is declared here so that macros can work, but it shouldn't
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be considered public. Don't access those fields directly, use the macros
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and functions instead! */
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typedef struct {
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PyObject_HEAD
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Py_buffer view;
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} PyMemoryViewObject;
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#ifdef __cplusplus
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}
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#endif
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#endif /* !Py_MEMORYOBJECT_H */
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