42 lines
953 B
Go
42 lines
953 B
Go
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package updater
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import (
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"context"
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"net"
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)
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func newResolver(resolverAddress string) *net.Resolver {
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return &net.Resolver{
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PreferGo: true,
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Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
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d := net.Dialer{}
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return d.DialContext(ctx, "udp", net.JoinHostPort(resolverAddress, "53"))
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},
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}
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}
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func newLookupIP(r *net.Resolver) lookupIPFunc {
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return func(ctx context.Context, host string) (ips []net.IP, err error) {
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addresses, err := r.LookupIPAddr(ctx, host)
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if err != nil {
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return nil, err
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}
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ips = make([]net.IP, len(addresses))
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for i := range addresses {
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ips[i] = addresses[i].IP
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}
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return ips, nil
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}
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}
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func resolveRepeat(ctx context.Context, lookupIP lookupIPFunc, host string, n int) (ips []net.IP, err error) {
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for i := 0; i < n; i++ {
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newIPs, err := lookupIP(ctx, host)
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if err != nil {
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return nil, err
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}
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ips = append(ips, newIPs...)
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}
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return uniqueSortedIPs(ips), nil
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}
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