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/*
* Copyright 2016-2019 Max Kellermann <max.kellermann@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``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
* FOUNDATION OR CONTRIBUTORS 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.
*/
#ifndef NET_ADDRESS_INFO_HXX
#define NET_ADDRESS_INFO_HXX
#include "SocketAddress.hxx"
#include <utility>
#ifdef _WIN32
#include <ws2tcpip.h>
#else
#include <netdb.h>
#endif
constexpr struct addrinfo
MakeAddrInfo(int flags, int family, int socktype, int protocol=0) noexcept
{
struct addrinfo ai{};
ai.ai_flags = flags;
ai.ai_family = family;
ai.ai_socktype = socktype;
ai.ai_protocol = protocol;
return ai;
}
class AddressInfo : addrinfo {
/* this class cannot be instantiated, it can only be cast from
a struct addrinfo pointer */
AddressInfo() = delete;
~AddressInfo() = delete;
public:
constexpr int GetFamily() const {
return ai_family;
}
constexpr int GetType() const {
return ai_socktype;
}
constexpr int GetProtocol() const {
return ai_protocol;
}
constexpr operator SocketAddress() const {
return {ai_addr, (SocketAddress::size_type)ai_addrlen};
}
};
class AddressInfoList {
struct addrinfo *value = nullptr;
public:
AddressInfoList() = default;
explicit AddressInfoList(struct addrinfo *_value):value(_value) {}
AddressInfoList(AddressInfoList &&src)
:value(std::exchange(src.value, nullptr)) {}
~AddressInfoList() {
freeaddrinfo(value);
}
AddressInfoList &operator=(AddressInfoList &&src) {
std::swap(value, src.value);
return *this;
}
bool empty() const {
return value == nullptr;
}
const AddressInfo &front() const {
return *(const AddressInfo *)value;
}
/**
* Pick the best address from the list, e.g. prefer IPv6 over
* IPv4 (if both are available). We do this because binding
* to an IPv6 wildcard address also allows accepting IPv4
* connections.
*/
gcc_pure
const AddressInfo &GetBest() const;
class const_iterator {
struct addrinfo *cursor;
public:
explicit constexpr const_iterator(struct addrinfo *_cursor)
:cursor(_cursor) {}
constexpr bool operator==(const_iterator other) const {
return cursor == other.cursor;
}
constexpr bool operator!=(const_iterator other) const {
return cursor != other.cursor;
}
const_iterator &operator++() {
cursor = cursor->ai_next;
return *this;
}
constexpr const AddressInfo &operator*() const {
return *(const AddressInfo *)cursor;
}
constexpr const AddressInfo *operator->() const {
return (const AddressInfo *)cursor;
}
};
const_iterator begin() const {
return const_iterator(value);
}
const_iterator end() const {
return const_iterator(nullptr);
}
};
#endif