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// Copyright 2010 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.
// (Raw) IP sockets
package net
// IPAddr represents the address of a IP end point.
type IPAddr struct {
IP IP
}
// Network returns the address's network name, "ip".
func (a *IPAddr) Network() string { return "ip" }
func (a *IPAddr) String() string {
if a == nil {
return "<nil>"
}
return a.IP.String()
}
// ResolveIPAddr parses addr as a IP address and resolves domain
// names to numeric addresses on the network net, which must be
// "ip", "ip4" or "ip6". A literal IPv6 host address must be
// enclosed in square brackets, as in "[::]".
func ResolveIPAddr(net, addr string) (*IPAddr, error) {
ip, err := hostToIP(net, addr)
if err != nil {
return nil, err
}
return &IPAddr{ip}, nil
}
// Convert "host" into IP address.
func hostToIP(net, host string) (ip IP, err error) {
var addr IP
// Try as an IP address.
addr = ParseIP(host)
if addr == nil {
filter := anyaddr
if net != "" && net[len(net)-1] == '4' {
filter = ipv4only
}
if net != "" && net[len(net)-1] == '6' {
filter = ipv6only
}
// Not an IP address. Try as a DNS name.
addrs, err1 := LookupHost(host)
if err1 != nil {
err = err1
goto Error
}
addr = firstFavoriteAddr(filter, addrs)
if addr == nil {
// should not happen
err = &AddrError{"LookupHost returned no suitable address", addrs[0]}
goto Error
}
}
return addr, nil
Error:
return nil, err
}
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