mirror of
https://github.com/matrix-construct/construct
synced 2024-11-17 23:40:57 +01:00
400 lines
9.6 KiB
C++
400 lines
9.6 KiB
C++
/*
|
|
* charybdis: 21st Century IRC++d
|
|
* util.h: Miscellaneous utilities
|
|
*
|
|
* Copyright (C) 2016 Charybdis Development Team
|
|
* Copyright (C) 2016 Jason Volk <jason@zemos.net>
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice is present in all copies.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
|
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
*/
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_ALLOCATOR_H
|
|
|
|
namespace ircd::allocator
|
|
{
|
|
struct state;
|
|
template<class T = char> struct dynamic;
|
|
template<class T = char, size_t = 512> struct fixed;
|
|
template<class T> struct node;
|
|
};
|
|
|
|
struct ircd::allocator::state
|
|
{
|
|
using word_t = unsigned long long;
|
|
using size_type = std::size_t;
|
|
|
|
size_t size { 0 };
|
|
word_t *avail { nullptr };
|
|
size_t last { 0 };
|
|
|
|
static uint byte(const uint &i) { return i / (sizeof(word_t) * 8); }
|
|
static uint bit(const uint &i) { return i % (sizeof(word_t) * 8); }
|
|
static word_t mask(const uint &pos) { return word_t(1) << bit(pos); }
|
|
|
|
bool test(const uint &pos) const { return avail[byte(pos)] & mask(pos); }
|
|
void bts(const uint &pos) { avail[byte(pos)] |= mask(pos); }
|
|
void btc(const uint &pos) { avail[byte(pos)] &= ~mask(pos); }
|
|
|
|
uint next(const size_t &n) const;
|
|
void deallocate(const uint &p, const size_t &n);
|
|
uint allocate(const size_t &n, const uint &hint = -1);
|
|
|
|
state(const size_t &size = 0,
|
|
word_t *const &avail = nullptr)
|
|
:size{size}
|
|
,avail{avail}
|
|
,last{0}
|
|
{}
|
|
};
|
|
|
|
template<class T,
|
|
size_t max>
|
|
struct ircd::allocator::fixed
|
|
:state
|
|
{
|
|
struct allocator;
|
|
|
|
std::array<word_t, max / 8> avail {{ 0 }};
|
|
std::array<T, max> buf alignas(16);
|
|
|
|
public:
|
|
allocator operator()();
|
|
operator allocator();
|
|
|
|
fixed()
|
|
:state{max, avail.data()}
|
|
{}
|
|
};
|
|
|
|
template<class T,
|
|
size_t size>
|
|
struct ircd::allocator::fixed<T, size>::allocator
|
|
{
|
|
using value_type = T;
|
|
using pointer = T *;
|
|
using const_pointer = const T *;
|
|
using reference = T &;
|
|
using const_reference = const T &;
|
|
using size_type = std::size_t;
|
|
using difference_type = std::ptrdiff_t;
|
|
|
|
fixed *s;
|
|
|
|
public:
|
|
template<class U, size_t S> struct rebind
|
|
{
|
|
using other = typename fixed<U, S>::allocator;
|
|
};
|
|
|
|
size_type max_size() const { return size; }
|
|
auto address(reference x) const { return &x; }
|
|
auto address(const_reference x) const { return &x; }
|
|
|
|
pointer allocate(const size_type &n, const const_pointer &hint = nullptr)
|
|
{
|
|
const uint hintpos(hint? hint - s->buf.data() : -1);
|
|
return s->buf.data() + s->state::allocate(n, hint);
|
|
}
|
|
|
|
void deallocate(const pointer &p, const size_type &n)
|
|
{
|
|
const uint pos(p - s->buf.data());
|
|
s->state::deallocate(pos, n);
|
|
}
|
|
|
|
template<class U, size_t S>
|
|
allocator(const typename fixed<U, S>::allocator &) noexcept
|
|
:s{reinterpret_cast<fixed *>(s.s)}
|
|
{}
|
|
|
|
allocator(fixed &s) noexcept
|
|
:s{&s}
|
|
{}
|
|
|
|
allocator(allocator &&) = default;
|
|
allocator(const allocator &) = default;
|
|
|
|
friend bool operator==(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
|
|
friend bool operator!=(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
};
|
|
|
|
template<class T,
|
|
size_t size>
|
|
typename ircd::allocator::fixed<T, size>::allocator
|
|
ircd::allocator::fixed<T, size>::operator()()
|
|
{
|
|
return { *this };
|
|
}
|
|
|
|
template<class T,
|
|
size_t size>
|
|
ircd::allocator::fixed<T, size>::operator
|
|
allocator()
|
|
{
|
|
return { *this };
|
|
}
|
|
|
|
template<class T>
|
|
struct ircd::allocator::dynamic
|
|
:state
|
|
{
|
|
struct allocator;
|
|
|
|
size_t head_size, data_size;
|
|
std::unique_ptr<uint8_t[]> arena;
|
|
T *buf;
|
|
|
|
public:
|
|
allocator operator()();
|
|
operator allocator();
|
|
|
|
dynamic(const size_t &size)
|
|
:state{size}
|
|
,head_size{size / 8}
|
|
,data_size{sizeof(T) * size + 16}
|
|
,arena
|
|
{
|
|
new __attribute__((aligned(16))) uint8_t[head_size + data_size]
|
|
}
|
|
,buf
|
|
{
|
|
reinterpret_cast<T *>(arena.get() + head_size + (head_size % 16))
|
|
}
|
|
{
|
|
state::avail = reinterpret_cast<word_t *>(arena.get());
|
|
}
|
|
};
|
|
|
|
template<class T>
|
|
struct ircd::allocator::dynamic<T>::allocator
|
|
{
|
|
using value_type = T;
|
|
using pointer = T *;
|
|
using const_pointer = const T *;
|
|
using reference = T &;
|
|
using const_reference = const T &;
|
|
using size_type = std::size_t;
|
|
using difference_type = std::ptrdiff_t;
|
|
|
|
dynamic *s;
|
|
|
|
public:
|
|
template<class U> struct rebind
|
|
{
|
|
using other = typename dynamic<U>::allocator;
|
|
};
|
|
|
|
size_type max_size() const { return s->size; }
|
|
auto address(reference x) const { return &x; }
|
|
auto address(const_reference x) const { return &x; }
|
|
|
|
pointer allocate(const size_type &n, const const_pointer &hint = nullptr)
|
|
{
|
|
const uint hintpos(hint? hint - s->buf : -1);
|
|
return s->buf + s->state::allocate(n, hintpos);
|
|
}
|
|
|
|
void deallocate(const pointer &p, const size_type &n)
|
|
{
|
|
const uint pos(p - s->buf);
|
|
s->state::deallocate(pos, n);
|
|
}
|
|
|
|
template<class U>
|
|
allocator(const typename dynamic<U>::allocator &) noexcept
|
|
:s{reinterpret_cast<dynamic *>(s.s)}
|
|
{}
|
|
|
|
allocator(dynamic &s) noexcept
|
|
:s{&s}
|
|
{}
|
|
|
|
allocator(allocator &&) = default;
|
|
allocator(const allocator &) = default;
|
|
|
|
friend bool operator==(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
|
|
friend bool operator!=(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
};
|
|
|
|
template<class T>
|
|
typename ircd::allocator::dynamic<T>::allocator
|
|
ircd::allocator::dynamic<T>::operator()()
|
|
{
|
|
return { *this };
|
|
}
|
|
|
|
template<class T>
|
|
ircd::allocator::dynamic<T>::operator
|
|
allocator()
|
|
{
|
|
return { *this };
|
|
}
|
|
|
|
template<class T>
|
|
struct ircd::allocator::node
|
|
{
|
|
struct allocator;
|
|
struct monotonic;
|
|
|
|
T *next {nullptr};
|
|
|
|
node() = default;
|
|
};
|
|
|
|
template<class T>
|
|
struct ircd::allocator::node<T>::allocator
|
|
{
|
|
using value_type = T;
|
|
using pointer = T *;
|
|
using const_pointer = const T *;
|
|
using reference = T &;
|
|
using const_reference = const T &;
|
|
using size_type = std::size_t;
|
|
using difference_type = std::ptrdiff_t;
|
|
|
|
node *s;
|
|
|
|
public:
|
|
template<class U> struct rebind
|
|
{
|
|
using other = typename node<U>::allocator;
|
|
};
|
|
|
|
size_type max_size() const { return std::numeric_limits<size_t>::max(); }
|
|
auto address(reference x) const { return &x; }
|
|
auto address(const_reference x) const { return &x; }
|
|
|
|
template<class U, class... args>
|
|
void construct(U *p, args&&... a)
|
|
{
|
|
new(p) U(std::forward<args>(a)...);
|
|
}
|
|
|
|
void construct(pointer p, const_reference val)
|
|
{
|
|
new(p) T(val);
|
|
}
|
|
|
|
pointer allocate(const size_type &n, const const_pointer &hint = nullptr)
|
|
{
|
|
assert(n == 1);
|
|
assert(hint == nullptr);
|
|
assert(s->next != nullptr);
|
|
return s->next;
|
|
}
|
|
|
|
void deallocate(const pointer &p, const size_type &n)
|
|
{
|
|
assert(n == 1);
|
|
}
|
|
|
|
template<class U>
|
|
allocator(const typename node<U>::allocator &s) noexcept
|
|
:s{reinterpret_cast<node *>(s.s)}
|
|
{
|
|
}
|
|
|
|
template<class U>
|
|
allocator(const U &s) noexcept
|
|
:s{reinterpret_cast<node *>(s.s)}
|
|
{
|
|
}
|
|
|
|
allocator(node &s) noexcept
|
|
:s{&s}
|
|
{
|
|
}
|
|
|
|
allocator() = default;
|
|
allocator(allocator &&) noexcept = default;
|
|
allocator(const allocator &) = default;
|
|
|
|
friend bool operator==(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
|
|
friend bool operator!=(const allocator &a, const allocator &b)
|
|
{
|
|
return &a == &b;
|
|
}
|
|
};
|
|
|
|
inline void
|
|
ircd::allocator::state::deallocate(const uint &pos,
|
|
const size_type &n)
|
|
{
|
|
for(size_t i(0); i < n; ++i)
|
|
btc(pos + i);
|
|
}
|
|
|
|
inline uint
|
|
ircd::allocator::state::allocate(const size_type &n,
|
|
const uint &hint)
|
|
{
|
|
const auto next(this->next(n));
|
|
if(unlikely(next >= size)) // No block of n was found anywhere (next is past-the-end)
|
|
throw std::bad_alloc();
|
|
|
|
for(size_t i(0); i < n; ++i)
|
|
bts(next + i);
|
|
|
|
last = next + n;
|
|
return next;
|
|
}
|
|
|
|
inline uint
|
|
ircd::allocator::state::next(const size_t &n)
|
|
const
|
|
{
|
|
uint ret(last), rem(n);
|
|
for(; ret < size && rem; ++ret)
|
|
if(test(ret))
|
|
rem = n;
|
|
else
|
|
--rem;
|
|
|
|
if(likely(!rem))
|
|
return ret - n;
|
|
|
|
for(ret = 0, rem = n; ret < last && rem; ++ret)
|
|
if(test(ret))
|
|
rem = n;
|
|
else
|
|
--rem;
|
|
|
|
if(unlikely(rem)) // The allocator should throw std::bad_alloc if !rem
|
|
return size;
|
|
|
|
return ret - n;
|
|
}
|