// Copyright 2012 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package ipv4 import ( "encoding/binary" "errors" "net" "unsafe" ) var ( errMissingAddress = errors.New("missing address") errMissingHeader = errors.New("missing header") errHeaderTooShort = errors.New("header too short") errBufferTooShort = errors.New("buffer too short") errInvalidConnType = errors.New("invalid conn type") errOpNoSupport = errors.New("operation not supported") errNoSuchInterface = errors.New("no such interface") errNoSuchMulticastInterface = errors.New("no such multicast interface") // See http://www.freebsd.org/doc/en/books/porters-handbook/freebsd-versions.html. freebsdVersion uint32 nativeEndian binary.ByteOrder ) func init() { i := uint32(1) b := (*[4]byte)(unsafe.Pointer(&i)) if b[0] == 1 { nativeEndian = binary.LittleEndian } else { nativeEndian = binary.BigEndian } } func boolint(b bool) int { if b { return 1 } return 0 } func netAddrToIP4(a net.Addr) net.IP { switch v := a.(type) { case *net.UDPAddr: if ip := v.IP.To4(); ip != nil { return ip } case *net.IPAddr: if ip := v.IP.To4(); ip != nil { return ip } } return nil }