38 lines
937 B
Go
38 lines
937 B
Go
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// Copyright 2014-2017 Ulrich Kunitz. 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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package lzma
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import (
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"errors"
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"io"
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)
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// ErrLimit indicates that the limit of the LimitedByteWriter has been
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// reached.
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var ErrLimit = errors.New("limit reached")
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// LimitedByteWriter provides a byte writer that can be written until a
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// limit is reached. The field N provides the number of remaining
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// bytes.
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type LimitedByteWriter struct {
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BW io.ByteWriter
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N int64
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}
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// WriteByte writes a single byte to the limited byte writer. It returns
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// ErrLimit if the limit has been reached. If the byte is successfully
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// written the field N of the LimitedByteWriter will be decremented by
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// one.
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func (l *LimitedByteWriter) WriteByte(c byte) error {
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if l.N <= 0 {
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return ErrLimit
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}
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if err := l.BW.WriteByte(c); err != nil {
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return err
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}
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l.N--
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return nil
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}
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