44 lines
1.4 KiB
Go
44 lines
1.4 KiB
Go
// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build tailscale_go
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// +build tailscale_go
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package deephash
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import "reflect"
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// iterKey returns the current iter key.
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// scratch is a re-usable reflect.Value.
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// iterKey may store the iter key in scratch and return scratch,
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// or it may allocate and return a new reflect.Value.
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func iterKey(iter *reflect.MapIter, scratch reflect.Value) reflect.Value {
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iter.SetKey(scratch)
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return scratch
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}
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// iterVal returns the current iter val.
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// scratch is a re-usable reflect.Value.
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// iterVal may store the iter val in scratch and return scratch,
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// or it may allocate and return a new reflect.Value.
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func iterVal(iter *reflect.MapIter, scratch reflect.Value) reflect.Value {
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iter.SetValue(scratch)
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return scratch
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}
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// mapIter returns a map iterator for mapVal.
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// scratch is a re-usable reflect.MapIter.
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// mapIter may re-use scratch and return it,
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// or it may allocate and return a new *reflect.MapIter.
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// If mapVal is the zero reflect.Value, mapIter may return nil.
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func mapIter(scratch *reflect.MapIter, mapVal reflect.Value) *reflect.MapIter {
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scratch.Reset(mapVal) // always Reset, to allow the caller to avoid pinning memory
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if !mapVal.IsValid() {
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// Returning scratch would also be OK.
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// Do this for consistency with the non-optimized version.
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return nil
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}
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return scratch
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}
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