forgejo/vendor/github.com/ulikunitz/xz/lzma/reader.go
6543 12a1f914f4
Vendor Update Go Libs (#13166)
* update github.com/alecthomas/chroma v0.8.0 -> v0.8.1

* github.com/blevesearch/bleve v1.0.10 -> v1.0.12

* editorconfig-core-go v2.1.1 -> v2.3.7

* github.com/gliderlabs/ssh v0.2.2 -> v0.3.1

* migrate editorconfig.ParseBytes to Parse

* github.com/shurcooL/vfsgen to 0d455de96546

* github.com/go-git/go-git/v5 v5.1.0 -> v5.2.0

* github.com/google/uuid v1.1.1 -> v1.1.2

* github.com/huandu/xstrings v1.3.0 -> v1.3.2

* github.com/klauspost/compress v1.10.11 -> v1.11.1

* github.com/markbates/goth v1.61.2 -> v1.65.0

* github.com/mattn/go-sqlite3 v1.14.0 -> v1.14.4

* github.com/mholt/archiver v3.3.0 -> v3.3.2

* github.com/microcosm-cc/bluemonday 4f7140c49acb -> v1.0.4

* github.com/minio/minio-go v7.0.4 -> v7.0.5

* github.com/olivere/elastic v7.0.9 -> v7.0.20

* github.com/urfave/cli v1.20.0 -> v1.22.4

* github.com/prometheus/client_golang v1.1.0 -> v1.8.0

* github.com/xanzy/go-gitlab v0.37.0 -> v0.38.1

* mvdan.cc/xurls v2.1.0 -> v2.2.0

Co-authored-by: Lauris BH <lauris@nix.lv>
2020-10-16 01:06:27 -04:00

100 lines
2.6 KiB
Go
Vendored

// Copyright 2014-2019 Ulrich Kunitz. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package lzma supports the decoding and encoding of LZMA streams.
// Reader and Writer support the classic LZMA format. Reader2 and
// Writer2 support the decoding and encoding of LZMA2 streams.
//
// The package is written completely in Go and doesn't rely on any external
// library.
package lzma
import (
"errors"
"io"
)
// ReaderConfig stores the parameters for the reader of the classic LZMA
// format.
type ReaderConfig struct {
DictCap int
}
// fill converts the zero values of the configuration to the default values.
func (c *ReaderConfig) fill() {
if c.DictCap == 0 {
c.DictCap = 8 * 1024 * 1024
}
}
// Verify checks the reader configuration for errors. Zero values will
// be replaced by default values.
func (c *ReaderConfig) Verify() error {
c.fill()
if !(MinDictCap <= c.DictCap && int64(c.DictCap) <= MaxDictCap) {
return errors.New("lzma: dictionary capacity is out of range")
}
return nil
}
// Reader provides a reader for LZMA files or streams.
type Reader struct {
lzma io.Reader
h header
d *decoder
}
// NewReader creates a new reader for an LZMA stream using the classic
// format. NewReader reads and checks the header of the LZMA stream.
func NewReader(lzma io.Reader) (r *Reader, err error) {
return ReaderConfig{}.NewReader(lzma)
}
// NewReader creates a new reader for an LZMA stream in the classic
// format. The function reads and verifies the the header of the LZMA
// stream.
func (c ReaderConfig) NewReader(lzma io.Reader) (r *Reader, err error) {
if err = c.Verify(); err != nil {
return nil, err
}
data := make([]byte, HeaderLen)
if _, err := io.ReadFull(lzma, data); err != nil {
if err == io.EOF {
return nil, errors.New("lzma: unexpected EOF")
}
return nil, err
}
r = &Reader{lzma: lzma}
if err = r.h.unmarshalBinary(data); err != nil {
return nil, err
}
if r.h.dictCap < MinDictCap {
return nil, errors.New("lzma: dictionary capacity too small")
}
dictCap := r.h.dictCap
if c.DictCap > dictCap {
dictCap = c.DictCap
}
state := newState(r.h.properties)
dict, err := newDecoderDict(dictCap)
if err != nil {
return nil, err
}
r.d, err = newDecoder(ByteReader(lzma), state, dict, r.h.size)
if err != nil {
return nil, err
}
return r, nil
}
// EOSMarker indicates that an EOS marker has been encountered.
func (r *Reader) EOSMarker() bool {
return r.d.eosMarker
}
// Read returns uncompressed data.
func (r *Reader) Read(p []byte) (n int, err error) {
return r.d.Read(p)
}