istio

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// Copyright Istio Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//     http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package validation
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import (
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	"encoding/binary"
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	"unsafe"
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)
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var nativeByteOrder binary.ByteOrder
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func init() {
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	var x uint16 = 0x0102
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	lowerByte := *(*byte)(unsafe.Pointer(&x))
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	switch lowerByte {
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	case 0x01:
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		nativeByteOrder = binary.BigEndian
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	case 0x02:
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		nativeByteOrder = binary.LittleEndian
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	default:
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		panic("Could not determine native byte order.")
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	}
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}
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// <arpa/inet.h>
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func ntohs(n16 uint16) uint16 {
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	if nativeByteOrder == binary.BigEndian {
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		return n16
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	}
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	return (n16&0xff00)>>8 | (n16&0xff)<<8
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}
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