github.com/iDigitalFlame/xmt@v0.5.4/com/c_no_compat.go (about)

     1  //go:build go1.18
     2  // +build go1.18
     3  
     4  // Copyright (C) 2020 - 2023 iDigitalFlame
     5  //
     6  // This program is free software: you can redistribute it and/or modify
     7  // it under the terms of the GNU General Public License as published by
     8  // the Free Software Foundation, either version 3 of the License, or
     9  // any later version.
    10  //
    11  // This program is distributed in the hope that it will be useful,
    12  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    13  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    14  // GNU General Public License for more details.
    15  //
    16  // You should have received a copy of the GNU General Public License
    17  // along with this program.  If not, see <https://www.gnu.org/licenses/>.
    18  //
    19  
    20  package com
    21  
    22  import (
    23  	"net"
    24  	"net/netip"
    25  	"syscall"
    26  )
    27  
    28  var emptyAddr netip.AddrPort
    29  
    30  type udpAddr netip.AddrPort
    31  type udpSockInternal interface {
    32  	WriteToUDPAddrPort([]byte, netip.AddrPort) (int, error)
    33  	ReadFromUDPAddrPort([]byte) (int, netip.AddrPort, error)
    34  }
    35  
    36  func (u udpAddr) IsValid() bool {
    37  	return netip.AddrPort(u).IsValid()
    38  }
    39  func (u udpAddr) String() string {
    40  	// NOTE(dij): This causes IPv4 addresses to weirdly be wrapped as an IPv6
    41  	//            address. This doesn't seem to affect how it works on IPv4, but
    42  	//            we'll watch it. It only makes IPv4 addresses print out as IPv6
    43  	//            formatted addresses.
    44  	return netip.AddrPort(u).String()
    45  }
    46  func (u *udpCompat) ReadPacket(p []byte) (int, udpAddr, error) {
    47  	n, a, err := u.udpSock.ReadFromUDPAddrPort(p)
    48  	return n, udpAddr(a), err
    49  }
    50  func (u *udpCompat) WritePacket(p []byte, a udpAddr) (int, error) {
    51  	return u.udpSock.WriteToUDPAddrPort(p, netip.AddrPort(a))
    52  }
    53  func (i *ipPacketConn) ReadFromUDPAddrPort(b []byte) (int, netip.AddrPort, error) {
    54  	// NOTE(dij): Have to add this as there's no support for the netip
    55  	//            package for IPConns.
    56  	n, a, err := i.ReadFrom(b)
    57  	if a == nil {
    58  		return n, emptyAddr, err
    59  	}
    60  	v, ok := a.(*net.IPAddr)
    61  	if !ok {
    62  		if err != nil {
    63  			return n, emptyAddr, err
    64  		}
    65  		return n, emptyAddr, syscall.EINVAL
    66  	}
    67  	x, _ := netip.AddrFromSlice(v.IP)
    68  	return n, netip.AddrPortFrom(x, 0), err
    69  }
    70  func (i *ipPacketConn) WriteToUDPAddrPort(b []byte, a netip.AddrPort) (int, error) {
    71  	return i.WriteTo(b, &net.IPAddr{IP: a.Addr().AsSlice()})
    72  }