docker-credential-helpers/registryurl/url_non_go18.go

//+build !go1.8

package registryurl

import (
	url "net/url"
	"strings"
)

func GetHostname(u *url.URL) string {
	return stripPort(u.Host)
}

func GetPort(u *url.URL) string {
	return portOnly(u.Host)
}

func stripPort(hostport string) string {
	colon := strings.IndexByte(hostport, ':')
	if colon == -1 {
		return hostport
	}
	if i := strings.IndexByte(hostport, ']'); i != -1 {
		return strings.TrimPrefix(hostport[:i], "[")
	}
	return hostport[:colon]
}

func portOnly(hostport string) string {
	colon := strings.IndexByte(hostport, ':')
	if colon == -1 {
		return ""
	}
	if i := strings.Index(hostport, "]:"); i != -1 {
		return hostport[i+len("]:"):]
	}
	if strings.Contains(hostport, "]") {
		return ""
	}
	return hostport[colon+len(":"):]
}