rexylib/include/rexy/binary.hpp

/**
	This file is a part of rexy's general purpose library
	Copyright (C) 2020 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef REXY_BINARY_HPP
#define REXY_BINARY_HPP

#include <cstdlib> //size_t
#include <utility> //move
#include <cstring> //memcpy
#include <type_traits>
#include "cx/utility.hpp" //max
#include "detail/default_allocator.hpp"
#include "steal.hpp"

#define STOP_STRICT_ALIAS_WARNING(x) (x)

namespace rexy{

	class binary_base
	{
	protected:
		char* m_data = nullptr;
		size_t m_size = 0;
		size_t m_cap = 0;
	public:
	protected:
		constexpr binary_base(void)noexcept = default;
		constexpr binary_base(char* data, size_t size)noexcept:
			m_data(data), m_cap(size){}
		constexpr binary_base(char* data, size_t cap, size_t size)noexcept:
			m_data(data), m_size(size), m_cap(cap){}
		template<class Allocator>
		binary_base(const binary_base& b)noexcept{}
		~binary_base(void)noexcept = default;

	public:
		constexpr char* release(void)noexcept{return cx::exchange(m_data, nullptr);}

		constexpr size_t size(void)const{return m_size;}
		constexpr size_t capacity(void)const{return m_cap;}
		constexpr char* get(void){return m_data;}
		constexpr const char* get(void)const{return m_data;}
		constexpr operator bool(void)const{return m_data;}

		constexpr char& operator[](size_t i)noexcept{return m_data[i];}
		constexpr const char& operator[](size_t i)const noexcept{return m_data[i];}

	};
	template<class Allocator = detail::default_allocator<>>
	class binary_data : public binary_base
	{
	public:
		using allocator_type = Allocator;
	public:
		constexpr binary_data(void)noexcept = default;
		binary_data(const char* data, size_t size)
			noexcept(noexcept(Allocator::copy(data, size))):
			binary_base(reinterpret_cast<char*>(Allocator::copy(data, size)), size){}
		constexpr binary_data(rexy::steal<char*> data, size_t size)noexcept:
			binary_base(data.value(), size){}
		constexpr binary_data(rexy::steal<char*> data, size_t cap, size_t size)noexcept:
			binary_base(data.value(), cap, size){}
		binary_data(const char* data, size_t cap, size_t size)
			noexcept(noexcept(Allocator::copy(data, size))):
			binary_base(reinterpret_cast<char*>(Allocator::copy(data, size)), cap, size){}
		binary_data(size_t size)
			noexcept(noexcept(Allocator::allocate(size))):
			binary_base(reinterpret_cast<char*>(Allocator::allocate(size)), size){}
		binary_data(const binary_data& b)
			noexcept(noexcept(Allocator::copy(b.m_data, b.m_cap))):
			binary_base(b.m_data, b.m_cap, b.m_size)
		{
			m_data = Allocator::copy(b.m_data, b.m_cap);
		}
		constexpr binary_data(binary_data&& b)noexcept:
			binary_base(cx::exchange(b.m_data, nullptr), b.m_cap, b.m_size){}
		~binary_data(void)
			noexcept(noexcept(Allocator::free(m_data)))
		{
			Allocator::free(m_data);
		}
		binary_data& operator=(const binary_data& b)
			noexcept(noexcept(Allocator::copy(b.m_data, b.m_size)))
		{
			binary_data<allocator_type> tmp(b);
			return (*this = std::move(tmp));
		}
		constexpr binary_data& operator=(binary_data&& b)noexcept{
			m_size = b.m_size;
			m_cap = b.m_cap;
			cx::swap(m_data, b.m_data);
			return *this;
		}
		void reset(void)
			noexcept(noexcept(Allocator::free(m_data)))
		{
			Allocator::free(m_data);
			m_data = nullptr;
			m_cap = m_size = 0;
		}
		void reset(char* val, size_t cap, size_t size = 0)
			noexcept(noexcept(Allocator::free(m_data)))
		{
			Allocator::free(m_data);
			m_data = val;
			m_cap = cap;
			m_size = size;
		}
		bool resize(size_t newsize)
			noexcept(noexcept(Allocator::allocate(0)) &&
			         noexcept(Allocator::free(nullptr)))
		{
			if(newsize < m_cap)
				return false;
			binary_data<allocator_type> tmp(newsize);
			if(!tmp)
				return false;
			memcpy(STOP_STRICT_ALIAS_WARNING(tmp).m_data, m_data, m_size);
			cx::swap(m_data, STOP_STRICT_ALIAS_WARNING(tmp).m_data);
			m_cap = STOP_STRICT_ALIAS_WARNING(tmp).m_cap;
			return true;
		}
		void append(const char* data, size_t len)
			noexcept(noexcept(Allocator::allocate(0)) &&
			         noexcept(Allocator::free(nullptr)))
		{
			if(m_size + len > m_cap)
				resize(cx::max(m_cap*2, m_size+len));
			memcpy(m_data+m_size, data, len);
			m_size += len;
		}
	};
	using binary = binary_data<>;

	namespace detail{
		std::true_type is_binary_type_helper(binary_base);
		std::false_type is_binary_type_helper(...);

		template<class T>
		struct is_binary_type{
			constexpr static bool value = std::is_same<decltype(is_binary_type_helper(std::declval<typename std::decay<T>::type>())),std::true_type>::value;
		};

		template<class... Ts>
		using enable_if_binary = std::enable_if_t<(is_binary_type<Ts>::value && ...),int>;
	}

	template<class Left, class Right, detail::enable_if_binary<Left,Right> = 0>
	bool operator==(Left&& l, Right&& r)noexcept{
		return l && r && l.size() == r.size() && l.capacity() == r.capacity() && !memcmp(l.get(), r.get(), l.size());
	}
	template<class Left, class Right, detail::enable_if_binary<Left,Right> = 0>
	bool operator!=(Left&& l, Right&& r)noexcept{
		return !(std::forward<Left>(l) == std::forward<Right>(r));
	}
	template<class All, class Alr>
	auto operator+(const rexy::binary_data<All>& l, const rexy::binary_data<Alr>& r)
		noexcept(std::is_nothrow_constructible<binary_data<All>, size_t>::value)
	{
		rexy::binary_data<All> retval(l.size() + r.size());
		memcpy(retval.get(), l.get(), l.size());
		memcpy(retval.get()+l.size(), r.get(), r.size());
		return retval;
	}
	template<class All, class Alr>
	decltype(auto) operator+=(rexy::binary_data<All>& l, const rexy::binary_data<Alr>& r)
		noexcept(noexcept(All::allocate(0)))
	{
		l.resize(l.size() + r.size());
		memcpy(l.get()+l.size(), r.get(), r.size());
		return l;
	}
} //namespace rexy

#undef STOP_STRICT_ALIAS_WARNING

#ifdef REXY_STRING_BASE_HPP
#include "detail/binary_string_conv.hpp"
#endif

#endif