AdGuardHome/internal/aghnet/addr.go

44 lines
1.0 KiB
Go

package aghnet
import (
"fmt"
"strings"
"github.com/AdguardTeam/golibs/stringutil"
)
// NormalizeDomain returns a lowercased version of host without the final dot,
// unless host is ".", in which case it returns it unchanged. That is a special
// case that to allow matching queries like:
//
// dig IN NS '.'
func NormalizeDomain(host string) (norm string) {
if host == "." {
return host
}
return strings.ToLower(strings.TrimSuffix(host, "."))
}
// NewDomainNameSet returns nil and error, if list has duplicate or empty domain
// name. Otherwise returns a set, which contains domain names normalized using
// [NormalizeDomain].
func NewDomainNameSet(list []string) (set *stringutil.Set, err error) {
set = stringutil.NewSet()
for i, host := range list {
if host == "" {
return nil, fmt.Errorf("at index %d: hostname is empty", i)
}
host = NormalizeDomain(host)
if set.Has(host) {
return nil, fmt.Errorf("duplicate hostname %q at index %d", host, i)
}
set.Add(host)
}
return set, nil
}