Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Includes/cpython/buffer.pxd

Index: third_party/cython/src/Cython/Includes/cpython/buffer.pxd
diff --git a/third_party/cython/src/Cython/Includes/cpython/buffer.pxd b/third_party/cython/src/Cython/Includes/cpython/buffer.pxd
new file mode 100644
index 0000000000000000000000000000000000000000..f5b63cb279c24bfe3cfa69004e2995210f8ea95a
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+++ b/third_party/cython/src/Cython/Includes/cpython/buffer.pxd
@@ -0,0 +1,109 @@
+# Please see the Python header files (object.h/abstract.h) for docs
+
+cdef extern from "Python.h":
+
+    cdef enum:
+        PyBUF_SIMPLE,
+        PyBUF_WRITABLE,
+        PyBUF_WRITEABLE, # backwards compatability
+        PyBUF_FORMAT,
+        PyBUF_ND,
+        PyBUF_STRIDES,
+        PyBUF_C_CONTIGUOUS,
+        PyBUF_F_CONTIGUOUS,
+        PyBUF_ANY_CONTIGUOUS,
+        PyBUF_INDIRECT,
+        PyBUF_CONTIG,
+        PyBUF_CONTIG_RO,
+        PyBUF_STRIDED,
+        PyBUF_STRIDED_RO,
+        PyBUF_RECORDS,
+        PyBUF_RECORDS_RO,
+        PyBUF_FULL,
+        PyBUF_FULL_RO,
+        PyBUF_READ,
+        PyBUF_WRITE,
+        PyBUF_SHADOW
+
+    bint PyObject_CheckBuffer(object obj)
+    # Return 1 if obj supports the buffer interface otherwise 0.
+
+    int PyObject_GetBuffer(object obj, Py_buffer *view, int flags) except -1
+    # Export obj into a Py_buffer, view. These arguments must never be
+    # NULL. The flags argument is a bit field indicating what kind of
+    # buffer the caller is prepared to deal with and therefore what
+    # kind of buffer the exporter is allowed to return. The buffer
+    # interface allows for complicated memory sharing possibilities,
+    # but some caller may not be able to handle all the complexity but
+    # may want to see if the exporter will let them take a simpler
+    # view to its memory.
+
+    # Some exporters may not be able to share memory in every possible
+    # way and may need to raise errors to signal to some consumers
+    # that something is just not possible. These errors should be a
+    # BufferError unless there is another error that is actually
+    # causing the problem. The exporter can use flags information to
+    # simplify how much of the Py_buffer structure is filled in with
+    # non-default values and/or raise an error if the object can’t
+    # support a simpler view of its memory.
+
+    # 0 is returned on success and -1 on error.
+
+    void PyBuffer_Release(Py_buffer *view)
+    # Release the buffer view. This should be called when the buffer
+    # is no longer being used as it may free memory from it.
+
+    void* PyBuffer_GetPointer(Py_buffer *view, Py_ssize_t *indices)
+    # ??
+
+    Py_ssize_t PyBuffer_SizeFromFormat(char *) # actually const char
+    # Return the implied ~Py_buffer.itemsize from the struct-stype
+    # ~Py_buffer.format
+
+    int PyBuffer_ToContiguous(void *buf, Py_buffer *view, Py_ssize_t len, char fort)
+    # ??
+
+    int PyBuffer_FromContiguous(Py_buffer *view, void *buf, Py_ssize_t len, char fort)
+    # ??
+
+    int PyObject_CopyToObject(object obj, void *buf, Py_ssize_t len, char fortran) except -1
+    # Copy len bytes of data pointed to by the contiguous chunk of
+    # memory pointed to by buf into the buffer exported by obj. The
+    # buffer must of course be writable. Return 0 on success and
+    # return -1 and raise an error on failure. If the object does not
+    # have a writable buffer, then an error is raised. If fortran is
+    # 'F', then if the object is multi-dimensional, then the data will
+    # be copied into the array in Fortran-style (first dimension
+    # varies the fastest). If fortran is 'C', then the data will be
+    # copied into the array in C-style (last dimension varies the
+    # fastest). If fortran is 'A', then it does not matter and the
+    # copy will be made in whatever way is more efficient.
+
+    int PyObject_CopyData(object dest, object src) except -1
+    # Copy the data from the src buffer to the buffer of destination
+
+    bint PyBuffer_IsContiguous(Py_buffer *view, char fort)
+    # Return 1 if the memory defined by the view is C-style (fortran
+    # is 'C') or Fortran-style (fortran is 'F') contiguous or either
+    # one (fortran is 'A'). Return 0 otherwise.
+
+    void PyBuffer_FillContiguousStrides(int ndims,
+                                        Py_ssize_t *shape,
+                                        Py_ssize_t *strides,
+                                        Py_ssize_t itemsize,
+                                        char fort)
+    # Fill the strides array with byte-strides of a contiguous
+    # (Fortran-style if fort is 'F' or C-style otherwise) array of the
+    # given shape with the given number of bytes per element.
+
+    int PyBuffer_FillInfo(Py_buffer *view, object exporter, void *buf,
+                          Py_ssize_t len, int readonly, int flags) except -1
+    # Fill in a buffer-info structure, view, correctly for an exporter
+    # that can only share a contiguous chunk of memory of “unsigned
+    # bytes” of the given length. Return 0 on success and -1 (with
+    # raising an error) on error.
+
+    # DEPRECATED HERE: do not cimport from here, cimport from cpython.object instead
+    object PyObject_Format(object obj, object format_spec)
+    # Takes an arbitrary object and returns the result of calling
+    # obj.__format__(format_spec).