xo-alloc2/include/xo/alloc2/visitor/AResourceVisitor.hpp
Roland Conybeare b1d2ae6f19 xo-gc stack: refactor + streamline.
Retiring unused Collector typealiases.
Fix #include topology.
Fix/improve write barrier setup.
2026-05-02 13:49:29 -04:00

81 lines
2.5 KiB
C++

/** @file AResourceVisitor.hpp
*
* Generated automagically from ingredients:
* 1. code generator:
* [xo-facet/codegen/genfacet]
* arguments:
* --input [idl/ResourceVisitor.json5]
* 2. jinja2 template for abstract facet .hpp file:
* [abstract_facet.hpp.j2]
* 3. idl for facet methods
* [idl/ResourceVisitor.json5]
**/
#pragma once
// includes (via {facet_includes})
#include "Allocator.hpp"
#include <xo/facet/obj.hpp>
#include <xo/facet/facet_implementation.hpp>
#include <xo/facet/typeseq.hpp>
// {pretext} here
namespace xo {
namespace mm {
using Copaque = const void *;
using Opaque = void *;
/**
Visitor to receive measured resource consumption
**/
class AResourceVisitor {
public:
/** @defgroup mm-resourcevisitor-type-traits **/
///@{
// types
/** integer identifying a type **/
using typeseq = xo::facet::typeseq;
using Copaque = const void *;
using Opaque = void *;
/** type for length of a sequence **/
using size_type = std::size_t;
///@}
/** @defgroup mm-resourcevisitor-methods **/
///@{
// const methods
/** An uninitialized AResourceVisitor instance will have zero vtable pointer (per {linux,osx} abi).
* Use case for this is narrow. We go to some lengths to avoid null vtable pointers. For example
* obj<AFacet> will have non-null vtable (via IFacet_Any) with all methods terminating.
**/
bool _has_null_vptr() const noexcept { return *reinterpret_cast<const void * const *>(this) == nullptr; }
/** RTTI: unique id# for actual runtime data representation **/
virtual typeseq _typeseq() const noexcept = 0;
/** destroy instance @p d; calls c++ dtor only for actual runtime type; does not recover memory **/
virtual void _drop(Opaque d) const noexcept = 0;
/** report memory consumption **/
virtual void on_allocator(Copaque data, obj<AAllocator> mm) const noexcept = 0;
// nonconst methods
///@}
}; /*AResourceVisitor*/
/** Implementation IResourceVisitor_DRepr of AResourceVisitor for state DRepr
* should provide a specialization:
*
* template <>
* struct xo::facet::FacetImplementation<AResourceVisitor, DRepr> {
* using Impltype = IResourceVisitor_DRepr;
* };
*
* then IResourceVisitor_ImplType<DRepr> --> IResourceVisitor_DRepr
**/
template <typename DRepr>
using IResourceVisitor_ImplType = xo::facet::FacetImplType<AResourceVisitor, DRepr>;
} /*namespace mm*/
} /*namespace xo*/
/* AResourceVisitor.hpp */