xgboost::common::AlignedResourceReadStream Class Reference

Wrap resource into a dmlc stream. More...

#include <io.h>

Inheritance diagram for xgboost::common::AlignedResourceReadStream:

Public Member Functions
	AlignedResourceReadStream (std::shared_ptr< ResourceHandler > resource)
std::shared_ptr< ResourceHandler >	Share () noexcept(true)
auto	Consume (std::size_t n_bytes) noexcept(true)
	Consume n_bytes of data, no copying is performed.
template<typename T >
auto	Consume (T *out) noexcept(false) -> std::enable_if_t< std::is_pod_v< T >, bool >
virtual std::size_t	Tell () noexcept(true)
std::size_t	Read (void *ptr, std::size_t n_bytes) noexcept(true)
	Read n_bytes of data, output is copied into ptr.
template<typename T >
auto	Read (T *out) noexcept(false) -> std::enable_if_t< std::is_pod_v< T >, bool >
	Read a primitive type.
template<typename T >
bool	Read (std::vector< T > *out) noexcept(true)
	Read a vector.

Detailed Description

Wrap resource into a dmlc stream.

This class is to facilitate the use of mmap. Caller can optionally use the Read() method or the Consume() method. The former copies data into output, while the latter makes copy only if it's a primitive type.

Input is required to be aligned to IOAlignment().

Member Function Documentation

Consume()

auto xgboost::common::AlignedResourceReadStream::Consume ( std::size_t  n_bytes )

inlinenoexcept

Consume n_bytes of data, no copying is performed.

Returns

A pair with the beginning pointer and the number of available bytes, which may be smaller than requested.

Read() [1/2]

template<typename T >

bool xgboost::common::AlignedResourceReadStream::Read ( std::vector< T > *  out )

inlinenoexcept

Read a vector.

Returns

Whether the read is successful.

Read() [2/2]

template<typename T >

auto xgboost::common::AlignedResourceReadStream::Read ( T *  out ) -> std::enable_if_t<std::is_pod_v<T>, bool>

inline

Read a primitive type.

Returns

Whether the read is successful.

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The documentation for this class was generated from the following files:

• External/xgboost/src/common/io.h
• External/xgboost/src/common/io.cc