39 lines
1015 B
Go
39 lines
1015 B
Go
// Copyright 2014 The zappy 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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// Copyright 2011 The Snappy-Go 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 SNAPPY-GO-LICENSE file.
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package zappy
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import (
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"encoding/binary"
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"errors"
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)
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// ErrCorrupt reports that the input is invalid.
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var ErrCorrupt = errors.New("zappy: corrupt input")
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// DecodedLen returns the length of the decoded block.
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func DecodedLen(src []byte) (int, error) {
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v, _, err := decodedLen(src)
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return v, err
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}
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// decodedLen returns the length of the decoded block and the number of bytes
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// that the length header occupied.
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func decodedLen(src []byte) (blockLen, headerLen int, err error) {
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v, n := binary.Uvarint(src)
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if n == 0 {
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return 0, 0, ErrCorrupt
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}
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if uint64(int(v)) != v {
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return 0, 0, errors.New("zappy: decoded block is too large")
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}
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return int(v), n, nil
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}
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