1
0
mirror of https://github.com/go-gitea/gitea.git synced 2024-12-04 14:46:57 -05:00
gitea/vendor/github.com/ulikunitz/xz/lzma/encoderdict.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

150 lines
3.4 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
import (
"errors"
"fmt"
"io"
)
// matcher is an interface that supports the identification of the next
// operation.
type matcher interface {
io.Writer
SetDict(d *encoderDict)
NextOp(rep [4]uint32) operation
}
// encoderDict provides the dictionary of the encoder. It includes an
// addtional buffer atop of the actual dictionary.
type encoderDict struct {
buf buffer
m matcher
head int64
capacity int
// preallocated array
data [maxMatchLen]byte
}
// newEncoderDict creates the encoder dictionary. The argument bufSize
// defines the size of the additional buffer.
func newEncoderDict(dictCap, bufSize int, m matcher) (d *encoderDict, err error) {
if !(1 <= dictCap && int64(dictCap) <= MaxDictCap) {
return nil, errors.New(
"lzma: dictionary capacity out of range")
}
if bufSize < 1 {
return nil, errors.New(
"lzma: buffer size must be larger than zero")
}
d = &encoderDict{
buf: *newBuffer(dictCap + bufSize),
capacity: dictCap,
m: m,
}
m.SetDict(d)
return d, nil
}
// Discard discards n bytes. Note that n must not be larger than
// MaxMatchLen.
func (d *encoderDict) Discard(n int) {
p := d.data[:n]
k, _ := d.buf.Read(p)
if k < n {
panic(fmt.Errorf("lzma: can't discard %d bytes", n))
}
d.head += int64(n)
d.m.Write(p)
}
// Len returns the data available in the encoder dictionary.
func (d *encoderDict) Len() int {
n := d.buf.Available()
if int64(n) > d.head {
return int(d.head)
}
return n
}
// DictLen returns the actual length of data in the dictionary.
func (d *encoderDict) DictLen() int {
if d.head < int64(d.capacity) {
return int(d.head)
}
return d.capacity
}
// Available returns the number of bytes that can be written by a
// following Write call.
func (d *encoderDict) Available() int {
return d.buf.Available() - d.DictLen()
}
// Write writes data into the dictionary buffer. Note that the position
// of the dictionary head will not be moved. If there is not enough
// space in the buffer ErrNoSpace will be returned.
func (d *encoderDict) Write(p []byte) (n int, err error) {
m := d.Available()
if len(p) > m {
p = p[:m]
err = ErrNoSpace
}
var e error
if n, e = d.buf.Write(p); e != nil {
err = e
}
return n, err
}
// Pos returns the position of the head.
func (d *encoderDict) Pos() int64 { return d.head }
// ByteAt returns the byte at the given distance.
func (d *encoderDict) ByteAt(distance int) byte {
if !(0 < distance && distance <= d.Len()) {
return 0
}
i := d.buf.rear - distance
if i < 0 {
i += len(d.buf.data)
}
return d.buf.data[i]
}
// CopyN copies the last n bytes from the dictionary into the provided
// writer. This is used for copying uncompressed data into an
// uncompressed segment.
func (d *encoderDict) CopyN(w io.Writer, n int) (written int, err error) {
if n <= 0 {
return 0, nil
}
m := d.Len()
if n > m {
n = m
err = ErrNoSpace
}
i := d.buf.rear - n
var e error
if i < 0 {
i += len(d.buf.data)
if written, e = w.Write(d.buf.data[i:]); e != nil {
return written, e
}
i = 0
}
var k int
k, e = w.Write(d.buf.data[i:d.buf.rear])
written += k
if e != nil {
err = e
}
return written, err
}
// Buffered returns the number of bytes in the buffer.
func (d *encoderDict) Buffered() int { return d.buf.Buffered() }