github.com/zhuohuang-hust/src-cbuild@v0.0.0-20230105071821-c7aab3e7c840/mergeCode/libnetwork/resolvconf/dns/resolvconf.go (about)

     1  package dns
     2  
     3  import (
     4  	"regexp"
     5  )
     6  
     7  // IPLocalhost is a regex patter for localhost IP address range.
     8  const IPLocalhost = `((127\.([0-9]{1,3}\.){2}[0-9]{1,3})|(::1)$)`
     9  
    10  var localhostIPRegexp = regexp.MustCompile(IPLocalhost)
    11  
    12  // IsLocalhost returns true if ip matches the localhost IP regular expression.
    13  // Used for determining if nameserver settings are being passed which are
    14  // localhost addresses
    15  func IsLocalhost(ip string) bool {
    16  	return localhostIPRegexp.MatchString(ip)
    17  }