2021-03-01 04:38:33 +05:30
|
|
|
// Copyright 2014-2021 Ulrich Kunitz. All rights reserved.
|
2020-06-06 02:17:39 +05:30
|
|
|
// Use of this source code is governed by a BSD-style
|
|
|
|
// license that can be found in the LICENSE file.
|
|
|
|
|
|
|
|
package lzma
|
|
|
|
|
|
|
|
import (
|
|
|
|
"errors"
|
|
|
|
"io"
|
|
|
|
)
|
|
|
|
|
|
|
|
// ErrLimit indicates that the limit of the LimitedByteWriter has been
|
|
|
|
// reached.
|
|
|
|
var ErrLimit = errors.New("limit reached")
|
|
|
|
|
|
|
|
// LimitedByteWriter provides a byte writer that can be written until a
|
|
|
|
// limit is reached. The field N provides the number of remaining
|
|
|
|
// bytes.
|
|
|
|
type LimitedByteWriter struct {
|
|
|
|
BW io.ByteWriter
|
|
|
|
N int64
|
|
|
|
}
|
|
|
|
|
|
|
|
// WriteByte writes a single byte to the limited byte writer. It returns
|
|
|
|
// ErrLimit if the limit has been reached. If the byte is successfully
|
|
|
|
// written the field N of the LimitedByteWriter will be decremented by
|
|
|
|
// one.
|
|
|
|
func (l *LimitedByteWriter) WriteByte(c byte) error {
|
|
|
|
if l.N <= 0 {
|
|
|
|
return ErrLimit
|
|
|
|
}
|
|
|
|
if err := l.BW.WriteByte(c); err != nil {
|
|
|
|
return err
|
|
|
|
}
|
|
|
|
l.N--
|
|
|
|
return nil
|
|
|
|
}
|