48 lines
1.8 KiB
Go
48 lines
1.8 KiB
Go
// The MIT License
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//
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// Copyright (c) 2019-2020, Cloudflare, Inc. and Apple, Inc. All rights reserved.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package odoh
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import (
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"encoding/binary"
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"fmt"
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)
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func encodeLengthPrefixedSlice(slice []byte) []byte {
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result := make([]byte, 2)
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binary.BigEndian.PutUint16(result, uint16(len(slice)))
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return append(result, slice...)
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}
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func decodeLengthPrefixedSlice(slice []byte) ([]byte, int, error) {
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if len(slice) < 2 {
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return nil, 0, fmt.Errorf("Expected at least 2 bytes of length encoded prefix")
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}
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length := binary.BigEndian.Uint16(slice)
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if int(2+length) > len(slice) {
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return nil, 0, fmt.Errorf("Insufficient data. Expected %d, got %d", 2+length, len(slice))
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}
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return slice[2 : 2+length], int(2 + length), nil
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}
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