38 lines
751 B
Go
38 lines
751 B
Go
// Copyright (c) HashiCorp, Inc.
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// SPDX-License-Identifier: MPL-2.0
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package dns
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import (
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"math/rand"
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"regexp"
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)
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// MaxLabelLength is the maximum length for a name that can be used in DNS.
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const MaxLabelLength = 63
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// InvalidNameRe is a regex that matches characters which can not be included in
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// a DNS name.
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var InvalidNameRe = regexp.MustCompile(`[^A-Za-z0-9\\-]+`)
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type RecursorStrategy string
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const (
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RecursorStrategySequential RecursorStrategy = "sequential"
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RecursorStrategyRandom RecursorStrategy = "random"
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)
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func (s RecursorStrategy) Indexes(max int) []int {
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switch s {
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case RecursorStrategyRandom:
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return rand.Perm(max)
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default:
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idxs := make([]int, max)
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for i := range idxs {
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idxs[i] = i
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}
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return idxs
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}
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}
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