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-rw-r--r--ext/pybind11/include/pybind11/buffer_info.h108
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diff --git a/ext/pybind11/include/pybind11/buffer_info.h b/ext/pybind11/include/pybind11/buffer_info.h
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+++ b/ext/pybind11/include/pybind11/buffer_info.h
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+/*
+ pybind11/buffer_info.h: Python buffer object interface
+
+ Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
+
+ All rights reserved. Use of this source code is governed by a
+ BSD-style license that can be found in the LICENSE file.
+*/
+
+#pragma once
+
+#include "detail/common.h"
+
+NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+
+/// Information record describing a Python buffer object
+struct buffer_info {
+ void *ptr = nullptr; // Pointer to the underlying storage
+ ssize_t itemsize = 0; // Size of individual items in bytes
+ ssize_t size = 0; // Total number of entries
+ std::string format; // For homogeneous buffers, this should be set to format_descriptor<T>::format()
+ ssize_t ndim = 0; // Number of dimensions
+ std::vector<ssize_t> shape; // Shape of the tensor (1 entry per dimension)
+ std::vector<ssize_t> strides; // Number of entries between adjacent entries (for each per dimension)
+
+ buffer_info() { }
+
+ buffer_info(void *ptr, ssize_t itemsize, const std::string &format, ssize_t ndim,
+ detail::any_container<ssize_t> shape_in, detail::any_container<ssize_t> strides_in)
+ : ptr(ptr), itemsize(itemsize), size(1), format(format), ndim(ndim),
+ shape(std::move(shape_in)), strides(std::move(strides_in)) {
+ if (ndim != (ssize_t) shape.size() || ndim != (ssize_t) strides.size())
+ pybind11_fail("buffer_info: ndim doesn't match shape and/or strides length");
+ for (size_t i = 0; i < (size_t) ndim; ++i)
+ size *= shape[i];
+ }
+
+ template <typename T>
+ buffer_info(T *ptr, detail::any_container<ssize_t> shape_in, detail::any_container<ssize_t> strides_in)
+ : buffer_info(private_ctr_tag(), ptr, sizeof(T), format_descriptor<T>::format(), static_cast<ssize_t>(shape_in->size()), std::move(shape_in), std::move(strides_in)) { }
+
+ buffer_info(void *ptr, ssize_t itemsize, const std::string &format, ssize_t size)
+ : buffer_info(ptr, itemsize, format, 1, {size}, {itemsize}) { }
+
+ template <typename T>
+ buffer_info(T *ptr, ssize_t size)
+ : buffer_info(ptr, sizeof(T), format_descriptor<T>::format(), size) { }
+
+ explicit buffer_info(Py_buffer *view, bool ownview = true)
+ : buffer_info(view->buf, view->itemsize, view->format, view->ndim,
+ {view->shape, view->shape + view->ndim}, {view->strides, view->strides + view->ndim}) {
+ this->view = view;
+ this->ownview = ownview;
+ }
+
+ buffer_info(const buffer_info &) = delete;
+ buffer_info& operator=(const buffer_info &) = delete;
+
+ buffer_info(buffer_info &&other) {
+ (*this) = std::move(other);
+ }
+
+ buffer_info& operator=(buffer_info &&rhs) {
+ ptr = rhs.ptr;
+ itemsize = rhs.itemsize;
+ size = rhs.size;
+ format = std::move(rhs.format);
+ ndim = rhs.ndim;
+ shape = std::move(rhs.shape);
+ strides = std::move(rhs.strides);
+ std::swap(view, rhs.view);
+ std::swap(ownview, rhs.ownview);
+ return *this;
+ }
+
+ ~buffer_info() {
+ if (view && ownview) { PyBuffer_Release(view); delete view; }
+ }
+
+private:
+ struct private_ctr_tag { };
+
+ buffer_info(private_ctr_tag, void *ptr, ssize_t itemsize, const std::string &format, ssize_t ndim,
+ detail::any_container<ssize_t> &&shape_in, detail::any_container<ssize_t> &&strides_in)
+ : buffer_info(ptr, itemsize, format, ndim, std::move(shape_in), std::move(strides_in)) { }
+
+ Py_buffer *view = nullptr;
+ bool ownview = false;
+};
+
+NAMESPACE_BEGIN(detail)
+
+template <typename T, typename SFINAE = void> struct compare_buffer_info {
+ static bool compare(const buffer_info& b) {
+ return b.format == format_descriptor<T>::format() && b.itemsize == (ssize_t) sizeof(T);
+ }
+};
+
+template <typename T> struct compare_buffer_info<T, detail::enable_if_t<std::is_integral<T>::value>> {
+ static bool compare(const buffer_info& b) {
+ return (size_t) b.itemsize == sizeof(T) && (b.format == format_descriptor<T>::value ||
+ ((sizeof(T) == sizeof(long)) && b.format == (std::is_unsigned<T>::value ? "L" : "l")) ||
+ ((sizeof(T) == sizeof(size_t)) && b.format == (std::is_unsigned<T>::value ? "N" : "n")));
+ }
+};
+
+NAMESPACE_END(detail)
+NAMESPACE_END(PYBIND11_NAMESPACE)