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#pragma once
#include <memory>
#include <new>
#include <utility>
#include <vector>
// based on boost::core::noinit_adaptor
// The goal is to avoid initialization of the content of a container,
// because setting several kB of uint8_t to 0 has a real cost if you
// do 100k times per second.
template<class Allocator>
struct noinit_adaptor: Allocator
{
template<class U>
struct rebind {
typedef noinit_adaptor<typename std::allocator_traits<Allocator>::template
rebind_alloc<U> > other;
};
noinit_adaptor(): Allocator() { }
template<class U>
noinit_adaptor(U&& u) noexcept : Allocator(std::forward<U>(u)) { }
template<class U>
noinit_adaptor(const noinit_adaptor<U>& u) noexcept : Allocator(static_cast<const U&>(u)) { }
template<class U>
void construct(U* p) {
::new((void*)p) U;
}
template<class U, class V, class... Args>
void construct(U* p, V&& v, Args&&... args) {
::new((void*)p) U(std::forward<V>(v), std::forward<Args>(args)...);
}
template<class U>
void destroy(U* p) {
p->~U();
}
};
template<class T, class U>
inline bool operator==(const noinit_adaptor<T>& lhs,
const noinit_adaptor<U>& rhs) noexcept
{
return static_cast<const T&>(lhs) == static_cast<const U&>(rhs);
}
template<class T, class U>
inline bool operator!=(const noinit_adaptor<T>& lhs,
const noinit_adaptor<U>& rhs) noexcept
{
return !(lhs == rhs);
}
template<class Allocator>
inline noinit_adaptor<Allocator> noinit_adapt(const Allocator& a) noexcept
{
return noinit_adaptor<Allocator>(a);
}
template<class T> using NoInitVector = std::vector<T, noinit_adaptor<std::allocator<T>>>;
using PacketBuffer = NoInitVector<uint8_t>;
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