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Diffstat (limited to 'ext/pybind11/include/pybind11/buffer_info.h')
-rw-r--r-- | ext/pybind11/include/pybind11/buffer_info.h | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/ext/pybind11/include/pybind11/buffer_info.h b/ext/pybind11/include/pybind11/buffer_info.h new file mode 100644 index 000000000..9f072fa73 --- /dev/null +++ b/ext/pybind11/include/pybind11/buffer_info.h @@ -0,0 +1,108 @@ +/* + 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) |