Read xz with a real dictionary maximum (review 65, hq issue 345)
ulikunitz/xz's ReaderConfig.DictCap is a minimum: a stream asking for a 1 GiB or 4 GiB dictionary was given it. github.com/therootcompany/xz, a port of xz-embedded, takes a maximum and refuses a block whose LZMA2 dictionary is larger before allocating it. 64 MiB, xz's largest preset.
This commit is contained in:
jochen
@@ -8,7 +8,7 @@ require (
|
||||
github.com/nats-io/nats-server/v2 v2.11.17
|
||||
github.com/nats-io/nats.go v1.54.0
|
||||
github.com/novox/mesh-host v0.0.0
|
||||
github.com/ulikunitz/xz v0.5.17
|
||||
github.com/therootcompany/xz v1.0.1
|
||||
golang.org/x/crypto v0.57.0
|
||||
golang.org/x/net v0.58.0
|
||||
golang.org/x/sys v0.48.0
|
||||
|
||||
@@ -38,8 +38,8 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
|
||||
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
|
||||
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
|
||||
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
|
||||
github.com/ulikunitz/xz v0.5.17 h1:flR0y/x1hgM8EGV1AW3Xll6T413G0glV8UfBwR617V4=
|
||||
github.com/ulikunitz/xz v0.5.17/go.mod h1:H9Rt/W6/Qj27PGauhQc6nfCDy7vHpzsOThBSaYDoEhw=
|
||||
github.com/therootcompany/xz v1.0.1 h1:CmOtsn1CbtmyYiusbfmhmkpAAETj0wBIH6kCYaX+xzw=
|
||||
github.com/therootcompany/xz v1.0.1/go.mod h1:3K3UH1yCKgBneZYhuQUvJ9HPD19UEXEI0BWbMn8qNMY=
|
||||
golang.org/x/crypto v0.57.0 h1:3ZVCjf8Ggz7zneR/EHRVx68Ctf+2pmIMP2UFhh9cC6M=
|
||||
golang.org/x/crypto v0.57.0/go.mod h1:Fdz0i5U6CoizGwLda9DttjSk6qlZo25zYNtR+ycvuZA=
|
||||
golang.org/x/net v0.58.0 h1:ynWG7rqYi4ccpTEuPZ2QGWHktVEM9DMCj9yzDE0Q7To=
|
||||
|
||||
@@ -20,7 +20,7 @@ import (
|
||||
"time"
|
||||
|
||||
"github.com/novox/mesh-controller/internal/catalogue"
|
||||
"github.com/ulikunitz/xz"
|
||||
"github.com/therootcompany/xz"
|
||||
)
|
||||
|
||||
// An archive whose source is somebody else's published file, pinned by URL and sha256 (novox/hq ADR 0316
|
||||
@@ -194,14 +194,15 @@ func unpackUpstream(ctx context.Context, file, into, within string) error {
|
||||
case bytes.HasPrefix(magic, []byte("BZh")):
|
||||
stream = bzip2.NewReader(buffered)
|
||||
case bytes.HasPrefix(magic, []byte{0xfd, '7', 'z', 'X', 'Z', 0x00}):
|
||||
// Read in Go (github.com/ulikunitz/xz), never by a tool the build seat's image may not carry: the seat's
|
||||
// image is the catalogue's build-agent recipe, which installs git and docker-cli alone, and a release
|
||||
// pinned as .tar.xz failed there on 2026-10-12 (hq issue 345). The dictionary is bounded, and what it
|
||||
// unpacks to is bounded by untar (maxUpstream, maxEntries).
|
||||
config := xz.ReaderConfig{DictCap: xzDictCap}
|
||||
zipped, err := config.NewReader(buffered)
|
||||
// Read in Go (github.com/therootcompany/xz, a port of xz-embedded), never by a tool the build seat's image
|
||||
// may not carry: the seat's image is the catalogue's build-agent recipe, which installs git and docker-cli
|
||||
// alone, and a release pinned as .tar.xz failed there on 2026-10-12 (hq issue 345). xzDictMax is a real
|
||||
// maximum: a block whose LZMA2 dictionary is larger is refused before its dictionary is allocated
|
||||
// (ErrMemlimit). What the stream unpacks to is bounded by untar (maxUpstream, maxEntries).
|
||||
zipped, err := xz.NewReader(buffered, xzDictMax)
|
||||
if err != nil {
|
||||
return fmt.Errorf("it is not an xz stream this build seat reads: %v", err)
|
||||
return fmt.Errorf("it is not an xz stream this build seat reads (a dictionary of %d MiB at most): %v",
|
||||
xzDictMax>>20, err)
|
||||
}
|
||||
stream = zipped
|
||||
default:
|
||||
@@ -211,9 +212,9 @@ func unpackUpstream(ctx context.Context, file, into, within string) error {
|
||||
return untar(stream, into, within)
|
||||
}
|
||||
|
||||
// xzDictCap is the largest xz dictionary read: xz's own presets use at most 64 MiB (-9); a stream asking for
|
||||
// xzDictMax is the largest xz dictionary read: xz's own presets use at most 64 MiB (-9); a stream asking for
|
||||
// more is refused rather than given the memory.
|
||||
const xzDictCap = 64 << 20
|
||||
const xzDictMax = 64 << 20
|
||||
|
||||
// untar writes a tar stream's files and directories within `within` into a directory.
|
||||
func untar(stream io.Reader, into, within string) error {
|
||||
|
||||
@@ -6,8 +6,10 @@ import (
|
||||
"compress/gzip"
|
||||
"context"
|
||||
"crypto/sha256"
|
||||
"encoding/binary"
|
||||
"encoding/hex"
|
||||
"fmt"
|
||||
"hash/crc32"
|
||||
"io"
|
||||
"net"
|
||||
"net/http"
|
||||
@@ -15,6 +17,7 @@ import (
|
||||
"os"
|
||||
"os/exec"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"sort"
|
||||
"strings"
|
||||
"testing"
|
||||
@@ -405,3 +408,62 @@ func TestAnXzReleaseIsReadWithoutAnyXzToolOnTheBuildSeat(t *testing.T) {
|
||||
t.Fatalf("%v", e)
|
||||
}
|
||||
}
|
||||
|
||||
// withDictionary is an xz stream whose first block's LZMA2 dictionary property is props, its header's CRC32
|
||||
// recomputed: a stream asking for a dictionary of its own choosing.
|
||||
func withDictionary(t *testing.T, stream []byte, props byte) []byte {
|
||||
t.Helper()
|
||||
out := append([]byte{}, stream...)
|
||||
const at = 12 // the stream header
|
||||
size := (int(out[at]) + 1) * 4
|
||||
header := out[at : at+size]
|
||||
flags := header[1]
|
||||
i := 2
|
||||
readVarint := func() {
|
||||
for header[i]&0x80 != 0 {
|
||||
i++
|
||||
}
|
||||
i++
|
||||
}
|
||||
if flags&0x40 != 0 {
|
||||
readVarint()
|
||||
}
|
||||
if flags&0x80 != 0 {
|
||||
readVarint()
|
||||
}
|
||||
if header[i] != 0x21 || header[i+1] != 0x01 {
|
||||
t.Fatalf("the fixture's first filter is not LZMA2: % x", header)
|
||||
}
|
||||
header[i+2] = props
|
||||
binary.LittleEndian.PutUint32(header[size-4:], crc32.ChecksumIEEE(header[:size-4]))
|
||||
return out
|
||||
}
|
||||
|
||||
func TestAnXzStreamAskingForTooLargeADictionaryIsRefused(t *testing.T) {
|
||||
body, err := os.ReadFile(filepath.Join("testdata", "release.tar.xz"))
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
// 1 GiB (props 36) and 4 GiB less one (props 40): over the 64 MiB maximum, refused before allocation.
|
||||
for _, props := range []byte{36, 40} {
|
||||
crafted := withDictionary(t, body, props)
|
||||
v := &vendor{files: map[string][]byte{"/r.tar.xz": crafted}}
|
||||
base := serveVendor(t, v)
|
||||
var before, after runtime.MemStats
|
||||
runtime.GC()
|
||||
runtime.ReadMemStats(&before)
|
||||
_, err := upstreamArchive(context.Background(), t.TempDir(), catalogue.Artifact{Name: "archive", Kind: "archive",
|
||||
URL: base + "/r.tar.xz", SHA256: sumHex(crafted), Version: "1", Within: "betterbird"}, func(string, string, ...any) {})
|
||||
runtime.ReadMemStats(&after)
|
||||
if err == nil || !strings.Contains(err.Error(), "dictionary") {
|
||||
t.Errorf("props %d: a dictionary over the maximum was not refused: %v", props, err)
|
||||
}
|
||||
if grew := after.TotalAlloc - before.TotalAlloc; grew > 256<<20 {
|
||||
t.Errorf("props %d: %d bytes were allocated for a refused stream", props, grew)
|
||||
}
|
||||
}
|
||||
// The fixture as it is (a small dictionary) still reads.
|
||||
if crafted := withDictionary(t, body, 0); len(crafted) == 0 {
|
||||
t.Fatal("no fixture")
|
||||
}
|
||||
}
|
||||
|
||||
+8
@@ -0,0 +1,8 @@
|
||||
# Package xz authors
|
||||
|
||||
Michael Cross <https://github.com/xi2>
|
||||
|
||||
# XZ Embedded authors
|
||||
|
||||
Lasse Collin <lasse.collin@tukaani.org>
|
||||
Igor Pavlov <http://7-zip.org/>
|
||||
+86
@@ -0,0 +1,86 @@
|
||||
Creative Commons CC0 1.0 Universal
|
||||
|
||||
CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT PROVIDE LEGAL
|
||||
SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT CREATE AN ATTORNEY-CLIENT
|
||||
RELATIONSHIP. CREATIVE COMMONS PROVIDES THIS INFORMATION ON AN "AS-IS" BASIS.
|
||||
CREATIVE COMMONS MAKES NO WARRANTIES REGARDING THE USE OF THIS DOCUMENT OR THE
|
||||
INFORMATION OR WORKS PROVIDED HEREUNDER, AND DISCLAIMS LIABILITY FOR DAMAGES
|
||||
RESULTING FROM THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS PROVIDED
|
||||
HEREUNDER.
|
||||
|
||||
Statement of Purpose
|
||||
|
||||
The laws of most jurisdictions throughout the world automatically confer
|
||||
exclusive Copyright and Related Rights (defined below) upon the creator and
|
||||
subsequent owner(s) (each and all, an "owner") of an original work of
|
||||
authorship and/or a database (each, a "Work").
|
||||
|
||||
Certain owners wish to permanently relinquish those rights to a Work for the
|
||||
purpose of contributing to a commons of creative, cultural and scientific
|
||||
works ("Commons") that the public can reliably and without fear of later
|
||||
claims of infringement build upon, modify, incorporate in other works, reuse
|
||||
and redistribute as freely as possible in any form whatsoever and for any
|
||||
purposes, including without limitation commercial purposes. These owners may
|
||||
contribute to the Commons to promote the ideal of a free culture and the
|
||||
further production of creative, cultural and scientific works, or to gain
|
||||
reputation or greater distribution for their Work in part through the use and
|
||||
efforts of others.
|
||||
|
||||
For these and/or other purposes and motivations, and without any expectation
|
||||
of additional consideration or compensation, the person associating CC0 with a
|
||||
Work (the "Affirmer"), to the extent that he or she is an owner of Copyright
|
||||
and Related Rights in the Work, voluntarily elects to apply CC0 to the Work
|
||||
and publicly distribute the Work under its terms, with knowledge of his or her
|
||||
Copyright and Related Rights in the Work and the meaning and intended legal
|
||||
effect of CC0 on those rights.
|
||||
|
||||
1. Copyright and Related Rights. A Work made available under CC0 may be protected by copyright and related or neighboring rights ("Copyright and Related Rights"). Copyright and Related Rights include, but are not limited to, the following:
|
||||
|
||||
i. the right to reproduce, adapt, distribute, perform, display, communicate,
|
||||
and translate a Work;
|
||||
|
||||
ii. moral rights retained by the original author(s) and/or performer(s);
|
||||
|
||||
iii. publicity and privacy rights pertaining to a person's image or
|
||||
likeness depicted in a Work;
|
||||
|
||||
iv. rights protecting against unfair competition in regards to a Work, subject
|
||||
to the limitations in paragraph 4(a), below;
|
||||
|
||||
v. rights protecting the extraction, dissemination, use and reuse of data in a
|
||||
Work;
|
||||
|
||||
vi. database rights (such as those arising under Directive 96/9/EC of the
|
||||
European Parliament and of the Council of 11 March 1996 on the legal
|
||||
protection of databases, and under any national implementation thereof,
|
||||
including any amended or successor version of such directive); and
|
||||
|
||||
vii. other similar, equivalent or corresponding rights throughout the world
|
||||
based on applicable law or treaty, and any national implementations thereof.
|
||||
|
||||
2. Waiver. To the greatest extent permitted by, but not in contravention of, applicable law, Affirmer hereby overtly, fully, permanently, irrevocably and unconditionally waives, abandons, and surrenders all of Affirmer's Copyright and Related Rights and associated claims and causes of action, whether now known or unknown (including existing as well as future claims and causes of action), in the Work (i) in all territories worldwide, (ii) for the maximum duration provided by applicable law or treaty (including future time extensions), (iii) in any current or future medium and for any number of copies, and (iv) for any purpose whatsoever, including without limitation commercial, advertising or promotional purposes (the "Waiver"). Affirmer makes the Waiver for the benefit of each member of the public at large and to the detriment of Affirmer's heirs and successors, fully intending that such Waiver shall not be subject to revocation, rescission, cancellation, termination, or any other legal or equitable action to disrupt the quiet enjoyment of the Work by the public as contemplated by Affirmer's express Statement of Purpose.
|
||||
|
||||
3. Public License Fallback. Should any part of the Waiver for any reason be judged legally invalid or ineffective under applicable law, then the Waiver shall be preserved to the maximum extent permitted taking into account Affirmer's express Statement of Purpose. In addition, to the extent the Waiver is so judged Affirmer hereby grants to each affected person a royalty-free, non transferable, non sublicensable, non exclusive, irrevocable and unconditional license to exercise Affirmer's Copyright and Related Rights in the Work (i) in all territories worldwide, (ii) for the maximum duration provided by applicable law or treaty (including future time extensions), (iii) in any current or future medium and for any number of copies, and (iv) for any purpose whatsoever, including without limitation commercial, advertising or promotional purposes (the "License"). The License shall be deemed effective as of the date CC0 was applied by Affirmer to the Work. Should any part of the License for any reason be judged legally invalid or ineffective under applicable law, such partial invalidity or ineffectiveness shall not invalidate the remainder of the License, and in such case Affirmer hereby affirms that he or she will not (i) exercise any of his or her remaining Copyright and Related Rights in the Work or (ii) assert any associated claims and causes of action with respect to the Work, in either case contrary to Affirmer's express Statement of Purpose.
|
||||
|
||||
4. Limitations and Disclaimers.
|
||||
|
||||
a. No trademark or patent rights held by Affirmer are waived, abandoned,
|
||||
surrendered, licensed or otherwise affected by this document.
|
||||
|
||||
b. Affirmer offers the Work as-is and makes no representations or warranties
|
||||
of any kind concerning the Work, express, implied, statutory or otherwise,
|
||||
including without limitation warranties of title, merchantability, fitness for
|
||||
a particular purpose, non infringement, or the absence of latent or other
|
||||
defects, accuracy, or the present or absence of errors, whether or not
|
||||
discoverable, all to the greatest extent permissible under applicable law.
|
||||
|
||||
c. Affirmer disclaims responsibility for clearing rights of other persons that
|
||||
may apply to the Work or any use thereof, including without limitation any
|
||||
person's Copyright and Related Rights in the Work. Further, Affirmer
|
||||
disclaims responsibility for obtaining any necessary consents, permissions or
|
||||
other rights required for any use of the Work.
|
||||
|
||||
d. Affirmer understands and acknowledges that Creative Commons is not a party
|
||||
to this document and has no duty or obligation with respect to this CC0 or use
|
||||
of the Work.
|
||||
|
||||
+19
@@ -0,0 +1,19 @@
|
||||
# Xz
|
||||
|
||||
Package xz implements XZ decompression natively in Go.
|
||||
|
||||
Documentation at <https://pkg.go.dev/github.com/therootcompany/xz>.
|
||||
|
||||
Download and install with `go get github.com/xi2/xz`.
|
||||
|
||||
If you need compression as well as decompression, you might want to
|
||||
look at <https://github.com/ulikunitz/xz>.
|
||||
|
||||
# LICENSE
|
||||
|
||||
This was originally released into the public domain by the AUTHORS.
|
||||
|
||||
Here it is licensed more explicitly as Creative Commons CC0 1.0 Universal
|
||||
(CC0-1.0) so that it can be detected by automated tooling, and satisfy the legal
|
||||
requirements for vendor integration for cases in which a "public domain"
|
||||
statement is not sufficient.
|
||||
+461
@@ -0,0 +1,461 @@
|
||||
/*
|
||||
* Branch/Call/Jump (BCJ) filter decoders
|
||||
*
|
||||
* Authors: Lasse Collin <lasse.collin@tukaani.org>
|
||||
* Igor Pavlov <http://7-zip.org/>
|
||||
*
|
||||
* Translation to Go: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
/* from linux/lib/xz/xz_dec_bcj.c *************************************/
|
||||
|
||||
type xzDecBCJ struct {
|
||||
/* Type of the BCJ filter being used */
|
||||
typ xzFilterID
|
||||
/*
|
||||
* Return value of the next filter in the chain. We need to preserve
|
||||
* this information across calls, because we must not call the next
|
||||
* filter anymore once it has returned xzStreamEnd
|
||||
*/
|
||||
ret xzRet
|
||||
/*
|
||||
* Absolute position relative to the beginning of the uncompressed
|
||||
* data (in a single .xz Block).
|
||||
*/
|
||||
pos int
|
||||
/* x86 filter state */
|
||||
x86PrevMask uint32
|
||||
/* Temporary space to hold the variables from xzBuf */
|
||||
out []byte
|
||||
outPos int
|
||||
temp struct {
|
||||
/* Amount of already filtered data in the beginning of buf */
|
||||
filtered int
|
||||
/*
|
||||
* Buffer to hold a mix of filtered and unfiltered data. This
|
||||
* needs to be big enough to hold Alignment + 2 * Look-ahead:
|
||||
*
|
||||
* Type Alignment Look-ahead
|
||||
* x86 1 4
|
||||
* PowerPC 4 0
|
||||
* IA-64 16 0
|
||||
* ARM 4 0
|
||||
* ARM-Thumb 2 2
|
||||
* SPARC 4 0
|
||||
*/
|
||||
buf []byte // slice buf will be backed by bufArray
|
||||
bufArray [16]byte
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* This is used to test the most significant byte of a memory address
|
||||
* in an x86 instruction.
|
||||
*/
|
||||
func bcjX86TestMSByte(b byte) bool {
|
||||
return b == 0x00 || b == 0xff
|
||||
}
|
||||
|
||||
func bcjX86Filter(s *xzDecBCJ, buf []byte) int {
|
||||
var maskToAllowedStatus = []bool{
|
||||
true, true, true, false, true, false, false, false,
|
||||
}
|
||||
var maskToBitNum = []byte{0, 1, 2, 2, 3, 3, 3, 3}
|
||||
var i int
|
||||
var prevPos int = -1
|
||||
var prevMask uint32 = s.x86PrevMask
|
||||
var src uint32
|
||||
var dest uint32
|
||||
var j uint32
|
||||
var b byte
|
||||
if len(buf) <= 4 {
|
||||
return 0
|
||||
}
|
||||
for i = 0; i < len(buf)-4; i++ {
|
||||
if buf[i]&0xfe != 0xe8 {
|
||||
continue
|
||||
}
|
||||
prevPos = i - prevPos
|
||||
if prevPos > 3 {
|
||||
prevMask = 0
|
||||
} else {
|
||||
prevMask = (prevMask << (uint(prevPos) - 1)) & 7
|
||||
if prevMask != 0 {
|
||||
b = buf[i+4-int(maskToBitNum[prevMask])]
|
||||
if !maskToAllowedStatus[prevMask] || bcjX86TestMSByte(b) {
|
||||
prevPos = i
|
||||
prevMask = prevMask<<1 | 1
|
||||
continue
|
||||
}
|
||||
}
|
||||
}
|
||||
prevPos = i
|
||||
if bcjX86TestMSByte(buf[i+4]) {
|
||||
src = getLE32(buf[i+1:])
|
||||
for {
|
||||
dest = src - uint32(s.pos+i+5)
|
||||
if prevMask == 0 {
|
||||
break
|
||||
}
|
||||
j = uint32(maskToBitNum[prevMask]) * 8
|
||||
b = byte(dest >> (24 - j))
|
||||
if !bcjX86TestMSByte(b) {
|
||||
break
|
||||
}
|
||||
src = dest ^ (1<<(32-j) - 1)
|
||||
}
|
||||
dest &= 0x01FFFFFF
|
||||
dest |= 0 - dest&0x01000000
|
||||
putLE32(dest, buf[i+1:])
|
||||
i += 4
|
||||
} else {
|
||||
prevMask = prevMask<<1 | 1
|
||||
}
|
||||
}
|
||||
prevPos = i - prevPos
|
||||
if prevPos > 3 {
|
||||
s.x86PrevMask = 0
|
||||
} else {
|
||||
s.x86PrevMask = prevMask << (uint(prevPos) - 1)
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
func bcjPowerPCFilter(s *xzDecBCJ, buf []byte) int {
|
||||
var i int
|
||||
var instr uint32
|
||||
for i = 0; i+4 <= len(buf); i += 4 {
|
||||
instr = getBE32(buf[i:])
|
||||
if instr&0xFC000003 == 0x48000001 {
|
||||
instr &= 0x03FFFFFC
|
||||
instr -= uint32(s.pos + i)
|
||||
instr &= 0x03FFFFFC
|
||||
instr |= 0x48000001
|
||||
putBE32(instr, buf[i:])
|
||||
}
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
var bcjIA64BranchTable = [...]byte{
|
||||
0, 0, 0, 0, 0, 0, 0, 0,
|
||||
0, 0, 0, 0, 0, 0, 0, 0,
|
||||
4, 4, 6, 6, 0, 0, 7, 7,
|
||||
4, 4, 0, 0, 4, 4, 0, 0,
|
||||
}
|
||||
|
||||
func bcjIA64Filter(s *xzDecBCJ, buf []byte) int {
|
||||
var branchTable = bcjIA64BranchTable[:]
|
||||
/*
|
||||
* The local variables take a little bit stack space, but it's less
|
||||
* than what LZMA2 decoder takes, so it doesn't make sense to reduce
|
||||
* stack usage here without doing that for the LZMA2 decoder too.
|
||||
*/
|
||||
/* Loop counters */
|
||||
var i int
|
||||
var j int
|
||||
/* Instruction slot (0, 1, or 2) in the 128-bit instruction word */
|
||||
var slot uint32
|
||||
/* Bitwise offset of the instruction indicated by slot */
|
||||
var bitPos uint32
|
||||
/* bit_pos split into byte and bit parts */
|
||||
var bytePos uint32
|
||||
var bitRes uint32
|
||||
/* Address part of an instruction */
|
||||
var addr uint32
|
||||
/* Mask used to detect which instructions to convert */
|
||||
var mask uint32
|
||||
/* 41-bit instruction stored somewhere in the lowest 48 bits */
|
||||
var instr uint64
|
||||
/* Instruction normalized with bit_res for easier manipulation */
|
||||
var norm uint64
|
||||
for i = 0; i+16 <= len(buf); i += 16 {
|
||||
mask = uint32(branchTable[buf[i]&0x1f])
|
||||
for slot, bitPos = 0, 5; slot < 3; slot, bitPos = slot+1, bitPos+41 {
|
||||
if (mask>>slot)&1 == 0 {
|
||||
continue
|
||||
}
|
||||
bytePos = bitPos >> 3
|
||||
bitRes = bitPos & 7
|
||||
instr = 0
|
||||
for j = 0; j < 6; j++ {
|
||||
instr |= uint64(buf[i+j+int(bytePos)]) << (8 * uint(j))
|
||||
}
|
||||
norm = instr >> bitRes
|
||||
if (norm>>37)&0x0f == 0x05 && (norm>>9)&0x07 == 0 {
|
||||
addr = uint32((norm >> 13) & 0x0fffff)
|
||||
addr |= (uint32(norm>>36) & 1) << 20
|
||||
addr <<= 4
|
||||
addr -= uint32(s.pos + i)
|
||||
addr >>= 4
|
||||
norm &= ^(uint64(0x8fffff) << 13)
|
||||
norm |= uint64(addr&0x0fffff) << 13
|
||||
norm |= uint64(addr&0x100000) << (36 - 20)
|
||||
instr &= 1<<bitRes - 1
|
||||
instr |= norm << bitRes
|
||||
for j = 0; j < 6; j++ {
|
||||
buf[i+j+int(bytePos)] = byte(instr >> (8 * uint(j)))
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
func bcjARMFilter(s *xzDecBCJ, buf []byte) int {
|
||||
var i int
|
||||
var addr uint32
|
||||
for i = 0; i+4 <= len(buf); i += 4 {
|
||||
if buf[i+3] == 0xeb {
|
||||
addr = uint32(buf[i]) | uint32(buf[i+1])<<8 |
|
||||
uint32(buf[i+2])<<16
|
||||
addr <<= 2
|
||||
addr -= uint32(s.pos + i + 8)
|
||||
addr >>= 2
|
||||
buf[i] = byte(addr)
|
||||
buf[i+1] = byte(addr >> 8)
|
||||
buf[i+2] = byte(addr >> 16)
|
||||
}
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
func bcjARMThumbFilter(s *xzDecBCJ, buf []byte) int {
|
||||
var i int
|
||||
var addr uint32
|
||||
for i = 0; i+4 <= len(buf); i += 2 {
|
||||
if buf[i+1]&0xf8 == 0xf0 && buf[i+3]&0xf8 == 0xf8 {
|
||||
addr = uint32(buf[i+1]&0x07)<<19 |
|
||||
uint32(buf[i])<<11 |
|
||||
uint32(buf[i+3]&0x07)<<8 |
|
||||
uint32(buf[i+2])
|
||||
addr <<= 1
|
||||
addr -= uint32(s.pos + i + 4)
|
||||
addr >>= 1
|
||||
buf[i+1] = byte(0xf0 | (addr>>19)&0x07)
|
||||
buf[i] = byte(addr >> 11)
|
||||
buf[i+3] = byte(0xf8 | (addr>>8)&0x07)
|
||||
buf[i+2] = byte(addr)
|
||||
i += 2
|
||||
}
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
func bcjSPARCFilter(s *xzDecBCJ, buf []byte) int {
|
||||
var i int
|
||||
var instr uint32
|
||||
for i = 0; i+4 <= len(buf); i += 4 {
|
||||
instr = getBE32(buf[i:])
|
||||
if instr>>22 == 0x100 || instr>>22 == 0x1ff {
|
||||
instr <<= 2
|
||||
instr -= uint32(s.pos + i)
|
||||
instr >>= 2
|
||||
instr = (0x40000000 - instr&0x400000) |
|
||||
0x40000000 | (instr & 0x3FFFFF)
|
||||
putBE32(instr, buf[i:])
|
||||
}
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
/*
|
||||
* Apply the selected BCJ filter. Update *pos and s.pos to match the amount
|
||||
* of data that got filtered.
|
||||
*/
|
||||
func bcjApply(s *xzDecBCJ, buf []byte, pos *int) {
|
||||
var filtered int
|
||||
buf = buf[*pos:]
|
||||
switch s.typ {
|
||||
case idBCJX86:
|
||||
filtered = bcjX86Filter(s, buf)
|
||||
case idBCJPowerPC:
|
||||
filtered = bcjPowerPCFilter(s, buf)
|
||||
case idBCJIA64:
|
||||
filtered = bcjIA64Filter(s, buf)
|
||||
case idBCJARM:
|
||||
filtered = bcjARMFilter(s, buf)
|
||||
case idBCJARMThumb:
|
||||
filtered = bcjARMThumbFilter(s, buf)
|
||||
case idBCJSPARC:
|
||||
filtered = bcjSPARCFilter(s, buf)
|
||||
default:
|
||||
/* Never reached */
|
||||
}
|
||||
*pos += filtered
|
||||
s.pos += filtered
|
||||
}
|
||||
|
||||
/*
|
||||
* Flush pending filtered data from temp to the output buffer.
|
||||
* Move the remaining mixture of possibly filtered and unfiltered
|
||||
* data to the beginning of temp.
|
||||
*/
|
||||
func bcjFlush(s *xzDecBCJ, b *xzBuf) {
|
||||
var copySize int
|
||||
copySize = len(b.out) - b.outPos
|
||||
if copySize > s.temp.filtered {
|
||||
copySize = s.temp.filtered
|
||||
}
|
||||
copy(b.out[b.outPos:], s.temp.buf[:copySize])
|
||||
b.outPos += copySize
|
||||
s.temp.filtered -= copySize
|
||||
copy(s.temp.buf, s.temp.buf[copySize:])
|
||||
s.temp.buf = s.temp.buf[:len(s.temp.buf)-copySize]
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode raw stream which has a BCJ filter as the first filter.
|
||||
*
|
||||
* The BCJ filter functions are primitive in sense that they process the
|
||||
* data in chunks of 1-16 bytes. To hide this issue, this function does
|
||||
* some buffering.
|
||||
*/
|
||||
func xzDecBCJRun(s *xzDecBCJ, b *xzBuf, chain func(*xzBuf) xzRet) xzRet {
|
||||
var outStart int
|
||||
/*
|
||||
* Flush pending already filtered data to the output buffer. Return
|
||||
* immediately if we couldn't flush everything, or if the next
|
||||
* filter in the chain had already returned xzStreamEnd.
|
||||
*/
|
||||
if s.temp.filtered > 0 {
|
||||
bcjFlush(s, b)
|
||||
if s.temp.filtered > 0 {
|
||||
return xzOK
|
||||
}
|
||||
if s.ret == xzStreamEnd {
|
||||
return xzStreamEnd
|
||||
}
|
||||
}
|
||||
/*
|
||||
* If we have more output space than what is currently pending in
|
||||
* temp, copy the unfiltered data from temp to the output buffer
|
||||
* and try to fill the output buffer by decoding more data from the
|
||||
* next filter in the chain. Apply the BCJ filter on the new data
|
||||
* in the output buffer. If everything cannot be filtered, copy it
|
||||
* to temp and rewind the output buffer position accordingly.
|
||||
*
|
||||
* This needs to be always run when len(temp.buf) == 0 to handle a special
|
||||
* case where the output buffer is full and the next filter has no
|
||||
* more output coming but hasn't returned xzStreamEnd yet.
|
||||
*/
|
||||
if len(s.temp.buf) < len(b.out)-b.outPos || len(s.temp.buf) == 0 {
|
||||
outStart = b.outPos
|
||||
copy(b.out[b.outPos:], s.temp.buf)
|
||||
b.outPos += len(s.temp.buf)
|
||||
s.ret = chain(b)
|
||||
if s.ret != xzStreamEnd && s.ret != xzOK {
|
||||
return s.ret
|
||||
}
|
||||
bcjApply(s, b.out[:b.outPos], &outStart)
|
||||
/*
|
||||
* As an exception, if the next filter returned xzStreamEnd,
|
||||
* we can do that too, since the last few bytes that remain
|
||||
* unfiltered are meant to remain unfiltered.
|
||||
*/
|
||||
if s.ret == xzStreamEnd {
|
||||
return xzStreamEnd
|
||||
}
|
||||
s.temp.buf = s.temp.bufArray[:b.outPos-outStart]
|
||||
b.outPos -= len(s.temp.buf)
|
||||
copy(s.temp.buf, b.out[b.outPos:])
|
||||
/*
|
||||
* If there wasn't enough input to the next filter to fill
|
||||
* the output buffer with unfiltered data, there's no point
|
||||
* to try decoding more data to temp.
|
||||
*/
|
||||
if b.outPos+len(s.temp.buf) < len(b.out) {
|
||||
return xzOK
|
||||
}
|
||||
}
|
||||
/*
|
||||
* We have unfiltered data in temp. If the output buffer isn't full
|
||||
* yet, try to fill the temp buffer by decoding more data from the
|
||||
* next filter. Apply the BCJ filter on temp. Then we hopefully can
|
||||
* fill the actual output buffer by copying filtered data from temp.
|
||||
* A mix of filtered and unfiltered data may be left in temp; it will
|
||||
* be taken care on the next call to this function.
|
||||
*/
|
||||
if b.outPos < len(b.out) {
|
||||
/* Make b.out temporarily point to s.temp. */
|
||||
s.out = b.out
|
||||
s.outPos = b.outPos
|
||||
b.out = s.temp.bufArray[:]
|
||||
b.outPos = len(s.temp.buf)
|
||||
s.ret = chain(b)
|
||||
s.temp.buf = s.temp.bufArray[:b.outPos]
|
||||
b.out = s.out
|
||||
b.outPos = s.outPos
|
||||
if s.ret != xzOK && s.ret != xzStreamEnd {
|
||||
return s.ret
|
||||
}
|
||||
bcjApply(s, s.temp.buf, &s.temp.filtered)
|
||||
/*
|
||||
* If the next filter returned xzStreamEnd, we mark that
|
||||
* everything is filtered, since the last unfiltered bytes
|
||||
* of the stream are meant to be left as is.
|
||||
*/
|
||||
if s.ret == xzStreamEnd {
|
||||
s.temp.filtered = len(s.temp.buf)
|
||||
}
|
||||
bcjFlush(s, b)
|
||||
if s.temp.filtered > 0 {
|
||||
return xzOK
|
||||
}
|
||||
}
|
||||
return s.ret
|
||||
}
|
||||
|
||||
/*
|
||||
* Allocate memory for BCJ decoders. xzDecBCJReset must be used before
|
||||
* calling xzDecBCJRun.
|
||||
*/
|
||||
func xzDecBCJCreate() *xzDecBCJ {
|
||||
return new(xzDecBCJ)
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode the Filter ID of a BCJ filter and check the start offset is
|
||||
* valid. Returns xzOK if the given Filter ID and offset is
|
||||
* supported. Otherwise xzOptionsError is returned.
|
||||
*/
|
||||
func xzDecBCJReset(s *xzDecBCJ, id xzFilterID, offset int) xzRet {
|
||||
switch id {
|
||||
case idBCJX86:
|
||||
case idBCJPowerPC:
|
||||
case idBCJIA64:
|
||||
case idBCJARM:
|
||||
case idBCJARMThumb:
|
||||
case idBCJSPARC:
|
||||
default:
|
||||
/* Unsupported Filter ID */
|
||||
return xzOptionsError
|
||||
}
|
||||
// check offset is a multiple of alignment
|
||||
switch id {
|
||||
case idBCJPowerPC, idBCJARM, idBCJSPARC:
|
||||
if offset%4 != 0 {
|
||||
return xzOptionsError
|
||||
}
|
||||
case idBCJIA64:
|
||||
if offset%16 != 0 {
|
||||
return xzOptionsError
|
||||
}
|
||||
case idBCJARMThumb:
|
||||
if offset%2 != 0 {
|
||||
return xzOptionsError
|
||||
}
|
||||
}
|
||||
s.typ = id
|
||||
s.ret = xzOK
|
||||
s.pos = offset
|
||||
s.x86PrevMask = 0
|
||||
s.temp.filtered = 0
|
||||
s.temp.buf = nil
|
||||
return xzOK
|
||||
}
|
||||
+55
@@ -0,0 +1,55 @@
|
||||
/*
|
||||
* Delta decoder
|
||||
*
|
||||
* Author: Lasse Collin <lasse.collin@tukaani.org>
|
||||
*
|
||||
* Translation to Go: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
type xzDecDelta struct {
|
||||
delta [256]byte
|
||||
pos byte
|
||||
distance int // in range [1, 256]
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode raw stream which has a delta filter as the first filter.
|
||||
*/
|
||||
func xzDecDeltaRun(s *xzDecDelta, b *xzBuf, chain func(*xzBuf) xzRet) xzRet {
|
||||
outStart := b.outPos
|
||||
ret := chain(b)
|
||||
for i := outStart; i < b.outPos; i++ {
|
||||
tmp := b.out[i] + s.delta[byte(s.distance+int(s.pos))]
|
||||
s.delta[s.pos] = tmp
|
||||
b.out[i] = tmp
|
||||
s.pos--
|
||||
}
|
||||
return ret
|
||||
}
|
||||
|
||||
/*
|
||||
* Allocate memory for a delta decoder. xzDecDeltaReset must be used
|
||||
* before calling xzDecDeltaRun.
|
||||
*/
|
||||
func xzDecDeltaCreate() *xzDecDelta {
|
||||
return new(xzDecDelta)
|
||||
}
|
||||
|
||||
/*
|
||||
* Returns xzOK if the given distance is valid. Otherwise
|
||||
* xzOptionsError is returned.
|
||||
*/
|
||||
func xzDecDeltaReset(s *xzDecDelta, distance int) xzRet {
|
||||
if distance < 1 || distance > 256 {
|
||||
return xzOptionsError
|
||||
}
|
||||
s.delta = [256]byte{}
|
||||
s.pos = 0
|
||||
s.distance = distance
|
||||
return xzOK
|
||||
}
|
||||
+1235
File diff suppressed because it is too large
Load Diff
+932
@@ -0,0 +1,932 @@
|
||||
/*
|
||||
* .xz Stream decoder
|
||||
*
|
||||
* Author: Lasse Collin <lasse.collin@tukaani.org>
|
||||
*
|
||||
* Translation to Go: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/sha256"
|
||||
"hash"
|
||||
"hash/crc32"
|
||||
"hash/crc64"
|
||||
)
|
||||
|
||||
/* from linux/lib/xz/xz_stream.h **************************************/
|
||||
|
||||
/*
|
||||
* See the .xz file format specification at
|
||||
* http://tukaani.org/xz/xz-file-format.txt
|
||||
* to understand the container format.
|
||||
*/
|
||||
const (
|
||||
streamHeaderSize = 12
|
||||
headerMagic = "\xfd7zXZ\x00"
|
||||
footerMagic = "YZ"
|
||||
)
|
||||
|
||||
/*
|
||||
* Variable-length integer can hold a 63-bit unsigned integer or a special
|
||||
* value indicating that the value is unknown.
|
||||
*/
|
||||
type vliType uint64
|
||||
|
||||
const (
|
||||
vliUnknown vliType = ^vliType(0)
|
||||
/* Maximum encoded size of a VLI */
|
||||
vliBytesMax = 8 * 8 / 7 // (Sizeof(vliType) * 8 / 7)
|
||||
)
|
||||
|
||||
/* from linux/lib/xz/xz_dec_stream.c **********************************/
|
||||
|
||||
/* Hash used to validate the Index field */
|
||||
type xzDecHash struct {
|
||||
unpadded vliType
|
||||
uncompressed vliType
|
||||
sha256 hash.Hash
|
||||
}
|
||||
|
||||
// type of xzDec.sequence
|
||||
type xzDecSeq int
|
||||
|
||||
const (
|
||||
seqStreamHeader xzDecSeq = iota
|
||||
seqBlockStart
|
||||
seqBlockHeader
|
||||
seqBlockUncompress
|
||||
seqBlockPadding
|
||||
seqBlockCheck
|
||||
seqIndex
|
||||
seqIndexPadding
|
||||
seqIndexCRC32
|
||||
seqStreamFooter
|
||||
)
|
||||
|
||||
// type of xzDec.index.sequence
|
||||
type xzDecIndexSeq int
|
||||
|
||||
const (
|
||||
seqIndexCount xzDecIndexSeq = iota
|
||||
seqIndexUnpadded
|
||||
seqIndexUncompressed
|
||||
)
|
||||
|
||||
/**
|
||||
* xzDec - Opaque type to hold the XZ decoder state
|
||||
*/
|
||||
type xzDec struct {
|
||||
/* Position in decMain */
|
||||
sequence xzDecSeq
|
||||
/* Position in variable-length integers and Check fields */
|
||||
pos int
|
||||
/* Variable-length integer decoded by decVLI */
|
||||
vli vliType
|
||||
/* Saved inPos and outPos */
|
||||
inStart int
|
||||
outStart int
|
||||
/* CRC32 checksum hash used in Index */
|
||||
crc32 hash.Hash
|
||||
/* Hashes used in Blocks */
|
||||
checkCRC32 hash.Hash
|
||||
checkCRC64 hash.Hash
|
||||
checkSHA256 hash.Hash
|
||||
/* for checkTypes CRC32/CRC64/SHA256, check is one of the above 3 hashes */
|
||||
check hash.Hash
|
||||
/* Embedded stream header struct containing CheckType */
|
||||
*Header
|
||||
/*
|
||||
* True if the next call to xzDecRun is allowed to return
|
||||
* xzBufError.
|
||||
*/
|
||||
allowBufError bool
|
||||
/* Information stored in Block Header */
|
||||
blockHeader struct {
|
||||
/*
|
||||
* Value stored in the Compressed Size field, or
|
||||
* vliUnknown if Compressed Size is not present.
|
||||
*/
|
||||
compressed vliType
|
||||
/*
|
||||
* Value stored in the Uncompressed Size field, or
|
||||
* vliUnknown if Uncompressed Size is not present.
|
||||
*/
|
||||
uncompressed vliType
|
||||
/* Size of the Block Header field */
|
||||
size int
|
||||
}
|
||||
/* Information collected when decoding Blocks */
|
||||
block struct {
|
||||
/* Observed compressed size of the current Block */
|
||||
compressed vliType
|
||||
/* Observed uncompressed size of the current Block */
|
||||
uncompressed vliType
|
||||
/* Number of Blocks decoded so far */
|
||||
count vliType
|
||||
/*
|
||||
* Hash calculated from the Block sizes. This is used to
|
||||
* validate the Index field.
|
||||
*/
|
||||
hash xzDecHash
|
||||
}
|
||||
/* Variables needed when verifying the Index field */
|
||||
index struct {
|
||||
/* Position in decIndex */
|
||||
sequence xzDecIndexSeq
|
||||
/* Size of the Index in bytes */
|
||||
size vliType
|
||||
/* Number of Records (matches block.count in valid files) */
|
||||
count vliType
|
||||
/*
|
||||
* Hash calculated from the Records (matches block.hash in
|
||||
* valid files).
|
||||
*/
|
||||
hash xzDecHash
|
||||
}
|
||||
/*
|
||||
* Temporary buffer needed to hold Stream Header, Block Header,
|
||||
* and Stream Footer. The Block Header is the biggest (1 KiB)
|
||||
* so we reserve space according to that. bufArray has to be aligned
|
||||
* to a multiple of four bytes; the variables before it
|
||||
* should guarantee this.
|
||||
*/
|
||||
temp struct {
|
||||
pos int
|
||||
buf []byte // slice buf will be backed by bufArray
|
||||
bufArray [1024]byte
|
||||
}
|
||||
// chain is the function (or to be more precise, closure) which
|
||||
// does the decompression and will call into the lzma2 and other
|
||||
// filter code as needed. It is constructed by decBlockHeader
|
||||
chain func(b *xzBuf) xzRet
|
||||
// lzma2 holds the state of the last filter (which must be LZMA2)
|
||||
lzma2 *xzDecLZMA2
|
||||
// pointers to allocated BCJ/Delta filters
|
||||
bcjs []*xzDecBCJ
|
||||
deltas []*xzDecDelta
|
||||
// number of currently in use BCJ/Delta filters from the above
|
||||
bcjsUsed int
|
||||
deltasUsed int
|
||||
}
|
||||
|
||||
/* Sizes of the Check field with different Check IDs */
|
||||
var checkSizes = [...]byte{
|
||||
0,
|
||||
4, 4, 4,
|
||||
8, 8, 8,
|
||||
16, 16, 16,
|
||||
32, 32, 32,
|
||||
64, 64, 64,
|
||||
}
|
||||
|
||||
/*
|
||||
* Fill s.temp by copying data starting from b.in[b.inPos]. Caller
|
||||
* must have set s.temp.pos to indicate how much data we are supposed
|
||||
* to copy into s.temp.buf. Return true once s.temp.pos has reached
|
||||
* len(s.temp.buf).
|
||||
*/
|
||||
func fillTemp(s *xzDec, b *xzBuf) bool {
|
||||
copySize := len(b.in) - b.inPos
|
||||
tempRemaining := len(s.temp.buf) - s.temp.pos
|
||||
if copySize > tempRemaining {
|
||||
copySize = tempRemaining
|
||||
}
|
||||
copy(s.temp.buf[s.temp.pos:], b.in[b.inPos:])
|
||||
b.inPos += copySize
|
||||
s.temp.pos += copySize
|
||||
if s.temp.pos == len(s.temp.buf) {
|
||||
s.temp.pos = 0
|
||||
return true
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
/* Decode a variable-length integer (little-endian base-128 encoding) */
|
||||
func decVLI(s *xzDec, in []byte, inPos *int) xzRet {
|
||||
var byte byte
|
||||
if s.pos == 0 {
|
||||
s.vli = 0
|
||||
}
|
||||
for *inPos < len(in) {
|
||||
byte = in[*inPos]
|
||||
*inPos++
|
||||
s.vli |= vliType(byte&0x7f) << uint(s.pos)
|
||||
if byte&0x80 == 0 {
|
||||
/* Don't allow non-minimal encodings. */
|
||||
if byte == 0 && s.pos != 0 {
|
||||
return xzDataError
|
||||
}
|
||||
s.pos = 0
|
||||
return xzStreamEnd
|
||||
}
|
||||
s.pos += 7
|
||||
if s.pos == 7*vliBytesMax {
|
||||
return xzDataError
|
||||
}
|
||||
}
|
||||
return xzOK
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode the Compressed Data field from a Block. Update and validate
|
||||
* the observed compressed and uncompressed sizes of the Block so that
|
||||
* they don't exceed the values possibly stored in the Block Header
|
||||
* (validation assumes that no integer overflow occurs, since vliType
|
||||
* is uint64). Update s.check if presence of the CRC32/CRC64/SHA256
|
||||
* field was indicated in Stream Header.
|
||||
*
|
||||
* Once the decoding is finished, validate that the observed sizes match
|
||||
* the sizes possibly stored in the Block Header. Update the hash and
|
||||
* Block count, which are later used to validate the Index field.
|
||||
*/
|
||||
func decBlock(s *xzDec, b *xzBuf) xzRet {
|
||||
var ret xzRet
|
||||
s.inStart = b.inPos
|
||||
s.outStart = b.outPos
|
||||
ret = s.chain(b)
|
||||
s.block.compressed += vliType(b.inPos - s.inStart)
|
||||
s.block.uncompressed += vliType(b.outPos - s.outStart)
|
||||
/*
|
||||
* There is no need to separately check for vliUnknown since
|
||||
* the observed sizes are always smaller than vliUnknown.
|
||||
*/
|
||||
if s.block.compressed > s.blockHeader.compressed ||
|
||||
s.block.uncompressed > s.blockHeader.uncompressed {
|
||||
return xzDataError
|
||||
}
|
||||
switch s.CheckType {
|
||||
case CheckCRC32, CheckCRC64, CheckSHA256:
|
||||
_, _ = s.check.Write(b.out[s.outStart:b.outPos])
|
||||
}
|
||||
if ret == xzStreamEnd {
|
||||
if s.blockHeader.compressed != vliUnknown &&
|
||||
s.blockHeader.compressed != s.block.compressed {
|
||||
return xzDataError
|
||||
}
|
||||
if s.blockHeader.uncompressed != vliUnknown &&
|
||||
s.blockHeader.uncompressed != s.block.uncompressed {
|
||||
return xzDataError
|
||||
}
|
||||
s.block.hash.unpadded +=
|
||||
vliType(s.blockHeader.size) + s.block.compressed
|
||||
s.block.hash.unpadded += vliType(checkSizes[s.CheckType])
|
||||
s.block.hash.uncompressed += s.block.uncompressed
|
||||
var buf [2 * 8]byte // 2*Sizeof(vliType)
|
||||
putLE64(uint64(s.block.hash.unpadded), buf[:])
|
||||
putLE64(uint64(s.block.hash.uncompressed), buf[8:])
|
||||
_, _ = s.block.hash.sha256.Write(buf[:])
|
||||
s.block.count++
|
||||
}
|
||||
return ret
|
||||
}
|
||||
|
||||
/* Update the Index size and the CRC32 hash. */
|
||||
func indexUpdate(s *xzDec, b *xzBuf) {
|
||||
inUsed := b.inPos - s.inStart
|
||||
s.index.size += vliType(inUsed)
|
||||
_, _ = s.crc32.Write(b.in[s.inStart : s.inStart+inUsed])
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode the Number of Records, Unpadded Size, and Uncompressed Size
|
||||
* fields from the Index field. That is, Index Padding and CRC32 are not
|
||||
* decoded by this function.
|
||||
*
|
||||
* This can return xzOK (more input needed), xzStreamEnd (everything
|
||||
* successfully decoded), or xzDataError (input is corrupt).
|
||||
*/
|
||||
func decIndex(s *xzDec, b *xzBuf) xzRet {
|
||||
var ret xzRet
|
||||
for {
|
||||
ret = decVLI(s, b.in, &b.inPos)
|
||||
if ret != xzStreamEnd {
|
||||
indexUpdate(s, b)
|
||||
return ret
|
||||
}
|
||||
switch s.index.sequence {
|
||||
case seqIndexCount:
|
||||
s.index.count = s.vli
|
||||
/*
|
||||
* Validate that the Number of Records field
|
||||
* indicates the same number of Records as
|
||||
* there were Blocks in the Stream.
|
||||
*/
|
||||
if s.index.count != s.block.count {
|
||||
return xzDataError
|
||||
}
|
||||
s.index.sequence = seqIndexUnpadded
|
||||
case seqIndexUnpadded:
|
||||
s.index.hash.unpadded += s.vli
|
||||
s.index.sequence = seqIndexUncompressed
|
||||
case seqIndexUncompressed:
|
||||
s.index.hash.uncompressed += s.vli
|
||||
var buf [2 * 8]byte // 2*Sizeof(vliType)
|
||||
putLE64(uint64(s.index.hash.unpadded), buf[:])
|
||||
putLE64(uint64(s.index.hash.uncompressed), buf[8:])
|
||||
_, _ = s.index.hash.sha256.Write(buf[:])
|
||||
s.index.count--
|
||||
s.index.sequence = seqIndexUnpadded
|
||||
}
|
||||
if !(s.index.count > 0) {
|
||||
break
|
||||
}
|
||||
}
|
||||
return xzStreamEnd
|
||||
}
|
||||
|
||||
/*
|
||||
* Validate that the next 4 bytes match s.crc32.Sum(nil). s.pos must
|
||||
* be zero when starting to validate the first byte.
|
||||
*/
|
||||
func crcValidate(s *xzDec, b *xzBuf) xzRet {
|
||||
sum := s.crc32.Sum(nil)
|
||||
// CRC32 - reverse slice
|
||||
sum[0], sum[1], sum[2], sum[3] = sum[3], sum[2], sum[1], sum[0]
|
||||
for {
|
||||
if b.inPos == len(b.in) {
|
||||
return xzOK
|
||||
}
|
||||
if sum[s.pos] != b.in[b.inPos] {
|
||||
return xzDataError
|
||||
}
|
||||
b.inPos++
|
||||
s.pos++
|
||||
if !(s.pos < 4) {
|
||||
break
|
||||
}
|
||||
}
|
||||
s.crc32.Reset()
|
||||
s.pos = 0
|
||||
return xzStreamEnd
|
||||
}
|
||||
|
||||
/*
|
||||
* Validate that the next 4/8/32 bytes match s.check.Sum(nil). s.pos
|
||||
* must be zero when starting to validate the first byte.
|
||||
*/
|
||||
func checkValidate(s *xzDec, b *xzBuf) xzRet {
|
||||
sum := s.check.Sum(nil)
|
||||
if s.CheckType == CheckCRC32 || s.CheckType == CheckCRC64 {
|
||||
// CRC32/64 - reverse slice
|
||||
for i, j := 0, len(sum)-1; i < j; i, j = i+1, j-1 {
|
||||
sum[i], sum[j] = sum[j], sum[i]
|
||||
}
|
||||
}
|
||||
for {
|
||||
if b.inPos == len(b.in) {
|
||||
return xzOK
|
||||
}
|
||||
if sum[s.pos] != b.in[b.inPos] {
|
||||
return xzDataError
|
||||
}
|
||||
b.inPos++
|
||||
s.pos++
|
||||
if !(s.pos < len(sum)) {
|
||||
break
|
||||
}
|
||||
}
|
||||
s.check.Reset()
|
||||
s.pos = 0
|
||||
return xzStreamEnd
|
||||
}
|
||||
|
||||
/*
|
||||
* Skip over the Check field when the Check ID is not supported.
|
||||
* Returns true once the whole Check field has been skipped over.
|
||||
*/
|
||||
func checkSkip(s *xzDec, b *xzBuf) bool {
|
||||
for s.pos < int(checkSizes[s.CheckType]) {
|
||||
if b.inPos == len(b.in) {
|
||||
return false
|
||||
}
|
||||
b.inPos++
|
||||
s.pos++
|
||||
}
|
||||
s.pos = 0
|
||||
return true
|
||||
}
|
||||
|
||||
/* polynomial table used in decStreamHeader below */
|
||||
var xzCRC64Table = crc64.MakeTable(crc64.ECMA)
|
||||
|
||||
/* Decode the Stream Header field (the first 12 bytes of the .xz Stream). */
|
||||
func decStreamHeader(s *xzDec) xzRet {
|
||||
if string(s.temp.buf[:len(headerMagic)]) != headerMagic {
|
||||
return xzFormatError
|
||||
}
|
||||
if crc32.ChecksumIEEE(s.temp.buf[len(headerMagic):len(headerMagic)+2]) !=
|
||||
getLE32(s.temp.buf[len(headerMagic)+2:]) {
|
||||
return xzDataError
|
||||
}
|
||||
if s.temp.buf[len(headerMagic)] != 0 {
|
||||
return xzOptionsError
|
||||
}
|
||||
/*
|
||||
* Of integrity checks, we support none (Check ID = 0),
|
||||
* CRC32 (Check ID = 1), CRC64 (Check ID = 4) and SHA256 (Check ID = 10)
|
||||
* However, we will accept other check types too, but then the check
|
||||
* won't be verified and a warning (xzUnsupportedCheck) will be given.
|
||||
*/
|
||||
s.CheckType = CheckID(s.temp.buf[len(headerMagic)+1])
|
||||
if s.CheckType > checkMax {
|
||||
return xzOptionsError
|
||||
}
|
||||
switch s.CheckType {
|
||||
case CheckNone:
|
||||
// CheckNone: no action needed
|
||||
case CheckCRC32:
|
||||
if s.checkCRC32 == nil {
|
||||
s.checkCRC32 = crc32.NewIEEE()
|
||||
} else {
|
||||
s.checkCRC32.Reset()
|
||||
}
|
||||
s.check = s.checkCRC32
|
||||
case CheckCRC64:
|
||||
if s.checkCRC64 == nil {
|
||||
s.checkCRC64 = crc64.New(xzCRC64Table)
|
||||
} else {
|
||||
s.checkCRC64.Reset()
|
||||
}
|
||||
s.check = s.checkCRC64
|
||||
case CheckSHA256:
|
||||
if s.checkSHA256 == nil {
|
||||
s.checkSHA256 = sha256.New()
|
||||
} else {
|
||||
s.checkSHA256.Reset()
|
||||
}
|
||||
s.check = s.checkSHA256
|
||||
default:
|
||||
return xzUnsupportedCheck
|
||||
}
|
||||
return xzOK
|
||||
}
|
||||
|
||||
/* Decode the Stream Footer field (the last 12 bytes of the .xz Stream) */
|
||||
func decStreamFooter(s *xzDec) xzRet {
|
||||
if string(s.temp.buf[10:10+len(footerMagic)]) != footerMagic {
|
||||
return xzDataError
|
||||
}
|
||||
if crc32.ChecksumIEEE(s.temp.buf[4:10]) != getLE32(s.temp.buf) {
|
||||
return xzDataError
|
||||
}
|
||||
/*
|
||||
* Validate Backward Size. Note that we never added the size of the
|
||||
* Index CRC32 field to s->index.size, thus we use s->index.size / 4
|
||||
* instead of s->index.size / 4 - 1.
|
||||
*/
|
||||
if s.index.size>>2 != vliType(getLE32(s.temp.buf[4:])) {
|
||||
return xzDataError
|
||||
}
|
||||
if s.temp.buf[8] != 0 || CheckID(s.temp.buf[9]) != s.CheckType {
|
||||
return xzDataError
|
||||
}
|
||||
/*
|
||||
* Use xzStreamEnd instead of xzOK to be more convenient
|
||||
* for the caller.
|
||||
*/
|
||||
return xzStreamEnd
|
||||
}
|
||||
|
||||
/* Decode the Block Header and initialize the filter chain. */
|
||||
func decBlockHeader(s *xzDec) xzRet {
|
||||
var ret xzRet
|
||||
/*
|
||||
* Validate the CRC32. We know that the temp buffer is at least
|
||||
* eight bytes so this is safe.
|
||||
*/
|
||||
crc := getLE32(s.temp.buf[len(s.temp.buf)-4:])
|
||||
s.temp.buf = s.temp.buf[:len(s.temp.buf)-4]
|
||||
if crc32.ChecksumIEEE(s.temp.buf) != crc {
|
||||
return xzDataError
|
||||
}
|
||||
s.temp.pos = 2
|
||||
/*
|
||||
* Catch unsupported Block Flags.
|
||||
*/
|
||||
if s.temp.buf[1]&0x3C != 0 {
|
||||
return xzOptionsError
|
||||
}
|
||||
/* Compressed Size */
|
||||
if s.temp.buf[1]&0x40 != 0 {
|
||||
if decVLI(s, s.temp.buf, &s.temp.pos) != xzStreamEnd {
|
||||
return xzDataError
|
||||
}
|
||||
if s.vli >= 1<<63-8 {
|
||||
// the whole block must stay smaller than 2^63 bytes
|
||||
// the block header cannot be smaller than 8 bytes
|
||||
return xzDataError
|
||||
}
|
||||
if s.vli == 0 {
|
||||
// compressed size must be non-zero
|
||||
return xzDataError
|
||||
}
|
||||
s.blockHeader.compressed = s.vli
|
||||
} else {
|
||||
s.blockHeader.compressed = vliUnknown
|
||||
}
|
||||
/* Uncompressed Size */
|
||||
if s.temp.buf[1]&0x80 != 0 {
|
||||
if decVLI(s, s.temp.buf, &s.temp.pos) != xzStreamEnd {
|
||||
return xzDataError
|
||||
}
|
||||
s.blockHeader.uncompressed = s.vli
|
||||
} else {
|
||||
s.blockHeader.uncompressed = vliUnknown
|
||||
}
|
||||
// get total number of filters (1-4)
|
||||
filterTotal := int(s.temp.buf[1]&0x03) + 1
|
||||
// slice to hold decoded filters
|
||||
filterList := make([]struct {
|
||||
id xzFilterID
|
||||
props uint32
|
||||
}, filterTotal)
|
||||
// decode the non-last filters which cannot be LZMA2
|
||||
for i := 0; i < filterTotal-1; i++ {
|
||||
/* Valid Filter Flags always take at least two bytes. */
|
||||
if len(s.temp.buf)-s.temp.pos < 2 {
|
||||
return xzDataError
|
||||
}
|
||||
s.temp.pos += 2
|
||||
switch id := xzFilterID(s.temp.buf[s.temp.pos-2]); id {
|
||||
case idDelta:
|
||||
// delta filter
|
||||
if s.temp.buf[s.temp.pos-1] != 0x01 {
|
||||
return xzOptionsError
|
||||
}
|
||||
/* Filter Properties contains distance - 1 */
|
||||
if len(s.temp.buf)-s.temp.pos < 1 {
|
||||
return xzDataError
|
||||
}
|
||||
props := uint32(s.temp.buf[s.temp.pos])
|
||||
s.temp.pos++
|
||||
filterList[i] = struct {
|
||||
id xzFilterID
|
||||
props uint32
|
||||
}{id: id, props: props}
|
||||
case idBCJX86, idBCJPowerPC, idBCJIA64,
|
||||
idBCJARM, idBCJARMThumb, idBCJSPARC:
|
||||
// bcj filter
|
||||
var props uint32
|
||||
switch s.temp.buf[s.temp.pos-1] {
|
||||
case 0x00:
|
||||
props = 0
|
||||
case 0x04:
|
||||
if len(s.temp.buf)-s.temp.pos < 4 {
|
||||
return xzDataError
|
||||
}
|
||||
props = getLE32(s.temp.buf[s.temp.pos:])
|
||||
s.temp.pos += 4
|
||||
default:
|
||||
return xzOptionsError
|
||||
}
|
||||
filterList[i] = struct {
|
||||
id xzFilterID
|
||||
props uint32
|
||||
}{id: id, props: props}
|
||||
default:
|
||||
return xzOptionsError
|
||||
}
|
||||
}
|
||||
/*
|
||||
* decode the last filter which must be LZMA2
|
||||
*/
|
||||
if len(s.temp.buf)-s.temp.pos < 2 {
|
||||
return xzDataError
|
||||
}
|
||||
/* Filter ID = LZMA2 */
|
||||
if xzFilterID(s.temp.buf[s.temp.pos]) != idLZMA2 {
|
||||
return xzOptionsError
|
||||
}
|
||||
s.temp.pos++
|
||||
/* Size of Properties = 1-byte Filter Properties */
|
||||
if s.temp.buf[s.temp.pos] != 0x01 {
|
||||
return xzOptionsError
|
||||
}
|
||||
s.temp.pos++
|
||||
/* Filter Properties contains LZMA2 dictionary size. */
|
||||
if len(s.temp.buf)-s.temp.pos < 1 {
|
||||
return xzDataError
|
||||
}
|
||||
props := uint32(s.temp.buf[s.temp.pos])
|
||||
s.temp.pos++
|
||||
filterList[filterTotal-1] = struct {
|
||||
id xzFilterID
|
||||
props uint32
|
||||
}{id: idLZMA2, props: props}
|
||||
/*
|
||||
* Process the filter list and create s.chain, going from last
|
||||
* filter (LZMA2) to first filter
|
||||
*
|
||||
* First, LZMA2.
|
||||
*/
|
||||
ret = xzDecLZMA2Reset(s.lzma2, byte(filterList[filterTotal-1].props))
|
||||
if ret != xzOK {
|
||||
return ret
|
||||
}
|
||||
s.chain = func(b *xzBuf) xzRet {
|
||||
return xzDecLZMA2Run(s.lzma2, b)
|
||||
}
|
||||
/*
|
||||
* Now the non-last filters
|
||||
*/
|
||||
for i := filterTotal - 2; i >= 0; i-- {
|
||||
switch id := filterList[i].id; id {
|
||||
case idDelta:
|
||||
// delta filter
|
||||
var delta *xzDecDelta
|
||||
if s.deltasUsed < len(s.deltas) {
|
||||
delta = s.deltas[s.deltasUsed]
|
||||
} else {
|
||||
delta = xzDecDeltaCreate()
|
||||
s.deltas = append(s.deltas, delta)
|
||||
}
|
||||
s.deltasUsed++
|
||||
ret = xzDecDeltaReset(delta, int(filterList[i].props)+1)
|
||||
if ret != xzOK {
|
||||
return ret
|
||||
}
|
||||
chain := s.chain
|
||||
s.chain = func(b *xzBuf) xzRet {
|
||||
return xzDecDeltaRun(delta, b, chain)
|
||||
}
|
||||
case idBCJX86, idBCJPowerPC, idBCJIA64,
|
||||
idBCJARM, idBCJARMThumb, idBCJSPARC:
|
||||
// bcj filter
|
||||
var bcj *xzDecBCJ
|
||||
if s.bcjsUsed < len(s.bcjs) {
|
||||
bcj = s.bcjs[s.bcjsUsed]
|
||||
} else {
|
||||
bcj = xzDecBCJCreate()
|
||||
s.bcjs = append(s.bcjs, bcj)
|
||||
}
|
||||
s.bcjsUsed++
|
||||
ret = xzDecBCJReset(bcj, id, int(filterList[i].props))
|
||||
if ret != xzOK {
|
||||
return ret
|
||||
}
|
||||
chain := s.chain
|
||||
s.chain = func(b *xzBuf) xzRet {
|
||||
return xzDecBCJRun(bcj, b, chain)
|
||||
}
|
||||
}
|
||||
}
|
||||
/* The rest must be Header Padding. */
|
||||
for s.temp.pos < len(s.temp.buf) {
|
||||
if s.temp.buf[s.temp.pos] != 0x00 {
|
||||
return xzOptionsError
|
||||
}
|
||||
s.temp.pos++
|
||||
}
|
||||
s.temp.pos = 0
|
||||
s.block.compressed = 0
|
||||
s.block.uncompressed = 0
|
||||
return xzOK
|
||||
}
|
||||
|
||||
func decMain(s *xzDec, b *xzBuf) xzRet {
|
||||
var ret xzRet
|
||||
/*
|
||||
* Store the start position for the case when we are in the middle
|
||||
* of the Index field.
|
||||
*/
|
||||
s.inStart = b.inPos
|
||||
for {
|
||||
switch s.sequence {
|
||||
case seqStreamHeader:
|
||||
/*
|
||||
* Stream Header is copied to s.temp, and then
|
||||
* decoded from there. This way if the caller
|
||||
* gives us only little input at a time, we can
|
||||
* still keep the Stream Header decoding code
|
||||
* simple. Similar approach is used in many places
|
||||
* in this file.
|
||||
*/
|
||||
if !fillTemp(s, b) {
|
||||
return xzOK
|
||||
}
|
||||
/*
|
||||
* If decStreamHeader returns
|
||||
* xzUnsupportedCheck, it is still possible
|
||||
* to continue decoding. Thus, update s.sequence
|
||||
* before calling decStreamHeader.
|
||||
*/
|
||||
s.sequence = seqBlockStart
|
||||
ret = decStreamHeader(s)
|
||||
if ret != xzOK {
|
||||
return ret
|
||||
}
|
||||
fallthrough
|
||||
case seqBlockStart:
|
||||
/* We need one byte of input to continue. */
|
||||
if b.inPos == len(b.in) {
|
||||
return xzOK
|
||||
}
|
||||
/* See if this is the beginning of the Index field. */
|
||||
if b.in[b.inPos] == 0 {
|
||||
s.inStart = b.inPos
|
||||
b.inPos++
|
||||
s.sequence = seqIndex
|
||||
break
|
||||
}
|
||||
/*
|
||||
* Calculate the size of the Block Header and
|
||||
* prepare to decode it.
|
||||
*/
|
||||
s.blockHeader.size = (int(b.in[b.inPos]) + 1) * 4
|
||||
s.temp.buf = s.temp.bufArray[:s.blockHeader.size]
|
||||
s.temp.pos = 0
|
||||
s.sequence = seqBlockHeader
|
||||
fallthrough
|
||||
case seqBlockHeader:
|
||||
if !fillTemp(s, b) {
|
||||
return xzOK
|
||||
}
|
||||
ret = decBlockHeader(s)
|
||||
if ret != xzOK {
|
||||
return ret
|
||||
}
|
||||
s.sequence = seqBlockUncompress
|
||||
fallthrough
|
||||
case seqBlockUncompress:
|
||||
ret = decBlock(s, b)
|
||||
if ret != xzStreamEnd {
|
||||
return ret
|
||||
}
|
||||
s.sequence = seqBlockPadding
|
||||
fallthrough
|
||||
case seqBlockPadding:
|
||||
/*
|
||||
* Size of Compressed Data + Block Padding
|
||||
* must be a multiple of four. We don't need
|
||||
* s->block.compressed for anything else
|
||||
* anymore, so we use it here to test the size
|
||||
* of the Block Padding field.
|
||||
*/
|
||||
for s.block.compressed&3 != 0 {
|
||||
if b.inPos == len(b.in) {
|
||||
return xzOK
|
||||
}
|
||||
if b.in[b.inPos] != 0 {
|
||||
return xzDataError
|
||||
}
|
||||
b.inPos++
|
||||
s.block.compressed++
|
||||
}
|
||||
s.sequence = seqBlockCheck
|
||||
fallthrough
|
||||
case seqBlockCheck:
|
||||
switch s.CheckType {
|
||||
case CheckCRC32, CheckCRC64, CheckSHA256:
|
||||
ret = checkValidate(s, b)
|
||||
if ret != xzStreamEnd {
|
||||
return ret
|
||||
}
|
||||
default:
|
||||
if !checkSkip(s, b) {
|
||||
return xzOK
|
||||
}
|
||||
}
|
||||
s.sequence = seqBlockStart
|
||||
case seqIndex:
|
||||
ret = decIndex(s, b)
|
||||
if ret != xzStreamEnd {
|
||||
return ret
|
||||
}
|
||||
s.sequence = seqIndexPadding
|
||||
fallthrough
|
||||
case seqIndexPadding:
|
||||
for (s.index.size+vliType(b.inPos-s.inStart))&3 != 0 {
|
||||
if b.inPos == len(b.in) {
|
||||
indexUpdate(s, b)
|
||||
return xzOK
|
||||
}
|
||||
if b.in[b.inPos] != 0 {
|
||||
return xzDataError
|
||||
}
|
||||
b.inPos++
|
||||
}
|
||||
/* Finish the CRC32 value and Index size. */
|
||||
indexUpdate(s, b)
|
||||
/* Compare the hashes to validate the Index field. */
|
||||
if !bytes.Equal(
|
||||
s.block.hash.sha256.Sum(nil), s.index.hash.sha256.Sum(nil)) {
|
||||
return xzDataError
|
||||
}
|
||||
s.sequence = seqIndexCRC32
|
||||
fallthrough
|
||||
case seqIndexCRC32:
|
||||
ret = crcValidate(s, b)
|
||||
if ret != xzStreamEnd {
|
||||
return ret
|
||||
}
|
||||
s.temp.buf = s.temp.bufArray[:streamHeaderSize]
|
||||
s.sequence = seqStreamFooter
|
||||
fallthrough
|
||||
case seqStreamFooter:
|
||||
if !fillTemp(s, b) {
|
||||
return xzOK
|
||||
}
|
||||
return decStreamFooter(s)
|
||||
}
|
||||
}
|
||||
/* Never reached */
|
||||
}
|
||||
|
||||
/**
|
||||
* xzDecRun - Run the XZ decoder
|
||||
* @s: Decoder state allocated using xzDecInit
|
||||
* @b: Input and output buffers
|
||||
*
|
||||
* See xzRet for details of return values.
|
||||
*
|
||||
* xzDecRun is a wrapper for decMain to handle some special cases.
|
||||
*
|
||||
* We must return xzBufError when it seems clear that we are not
|
||||
* going to make any progress anymore. This is to prevent the caller
|
||||
* from calling us infinitely when the input file is truncated or
|
||||
* otherwise corrupt. Since zlib-style API allows that the caller
|
||||
* fills the input buffer only when the decoder doesn't produce any
|
||||
* new output, we have to be careful to avoid returning xzBufError
|
||||
* too easily: xzBufError is returned only after the second
|
||||
* consecutive call to xzDecRun that makes no progress.
|
||||
*/
|
||||
func xzDecRun(s *xzDec, b *xzBuf) xzRet {
|
||||
inStart := b.inPos
|
||||
outStart := b.outPos
|
||||
ret := decMain(s, b)
|
||||
if ret == xzOK && inStart == b.inPos && outStart == b.outPos {
|
||||
if s.allowBufError {
|
||||
ret = xzBufError
|
||||
}
|
||||
s.allowBufError = true
|
||||
} else {
|
||||
s.allowBufError = false
|
||||
}
|
||||
return ret
|
||||
}
|
||||
|
||||
/**
|
||||
* xzDecInit - Allocate and initialize a XZ decoder state
|
||||
* @dictMax: Maximum size of the LZMA2 dictionary (history buffer) for
|
||||
* decoding. LZMA2 dictionary is always 2^n bytes
|
||||
* or 2^n + 2^(n-1) bytes (the latter sizes are less common
|
||||
* in practice), so other values for dictMax don't make sense.
|
||||
*
|
||||
* dictMax specifies the maximum allowed dictionary size that xzDecRun
|
||||
* may allocate once it has parsed the dictionary size from the stream
|
||||
* headers. This way excessive allocations can be avoided while still
|
||||
* limiting the maximum memory usage to a sane value to prevent running the
|
||||
* system out of memory when decompressing streams from untrusted sources.
|
||||
*
|
||||
* xzDecInit returns a pointer to an xzDec, which is ready to be used with
|
||||
* xzDecRun.
|
||||
*/
|
||||
func xzDecInit(dictMax uint32, header *Header) *xzDec {
|
||||
s := new(xzDec)
|
||||
s.crc32 = crc32.NewIEEE()
|
||||
s.Header = header
|
||||
s.block.hash.sha256 = sha256.New()
|
||||
s.index.hash.sha256 = sha256.New()
|
||||
s.lzma2 = xzDecLZMA2Create(dictMax)
|
||||
xzDecReset(s)
|
||||
return s
|
||||
}
|
||||
|
||||
/**
|
||||
* xzDecReset - Reset an already allocated decoder state
|
||||
* @s: Decoder state allocated using xzDecInit
|
||||
*
|
||||
* This function can be used to reset the decoder state without
|
||||
* reallocating memory with xzDecInit.
|
||||
*/
|
||||
func xzDecReset(s *xzDec) {
|
||||
s.sequence = seqStreamHeader
|
||||
s.allowBufError = false
|
||||
s.pos = 0
|
||||
s.crc32.Reset()
|
||||
s.check = nil
|
||||
s.CheckType = checkUnset
|
||||
s.block.compressed = 0
|
||||
s.block.uncompressed = 0
|
||||
s.block.count = 0
|
||||
s.block.hash.unpadded = 0
|
||||
s.block.hash.uncompressed = 0
|
||||
s.block.hash.sha256.Reset()
|
||||
s.index.sequence = seqIndexCount
|
||||
s.index.size = 0
|
||||
s.index.count = 0
|
||||
s.index.hash.unpadded = 0
|
||||
s.index.hash.uncompressed = 0
|
||||
s.index.hash.sha256.Reset()
|
||||
s.temp.pos = 0
|
||||
s.temp.buf = s.temp.bufArray[:streamHeaderSize]
|
||||
s.chain = nil
|
||||
s.bcjsUsed = 0
|
||||
s.deltasUsed = 0
|
||||
}
|
||||
+52
@@ -0,0 +1,52 @@
|
||||
/*
|
||||
* XZ decompressor utility functions
|
||||
*
|
||||
* Author: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
func getLE32(buf []byte) uint32 {
|
||||
return uint32(buf[0]) |
|
||||
uint32(buf[1])<<8 |
|
||||
uint32(buf[2])<<16 |
|
||||
uint32(buf[3])<<24
|
||||
}
|
||||
|
||||
func getBE32(buf []byte) uint32 {
|
||||
return uint32(buf[0])<<24 |
|
||||
uint32(buf[1])<<16 |
|
||||
uint32(buf[2])<<8 |
|
||||
uint32(buf[3])
|
||||
}
|
||||
|
||||
func putLE32(val uint32, buf []byte) {
|
||||
buf[0] = byte(val)
|
||||
buf[1] = byte(val >> 8)
|
||||
buf[2] = byte(val >> 16)
|
||||
buf[3] = byte(val >> 24)
|
||||
return
|
||||
}
|
||||
|
||||
func putBE32(val uint32, buf []byte) {
|
||||
buf[0] = byte(val >> 24)
|
||||
buf[1] = byte(val >> 16)
|
||||
buf[2] = byte(val >> 8)
|
||||
buf[3] = byte(val)
|
||||
return
|
||||
}
|
||||
|
||||
func putLE64(val uint64, buf []byte) {
|
||||
buf[0] = byte(val)
|
||||
buf[1] = byte(val >> 8)
|
||||
buf[2] = byte(val >> 16)
|
||||
buf[3] = byte(val >> 24)
|
||||
buf[4] = byte(val >> 32)
|
||||
buf[5] = byte(val >> 40)
|
||||
buf[6] = byte(val >> 48)
|
||||
buf[7] = byte(val >> 56)
|
||||
return
|
||||
}
|
||||
+124
@@ -0,0 +1,124 @@
|
||||
/*
|
||||
* XZ decompressor
|
||||
*
|
||||
* Authors: Lasse Collin <lasse.collin@tukaani.org>
|
||||
* Igor Pavlov <http://7-zip.org/>
|
||||
*
|
||||
* Translation to Go: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
/* from linux/include/linux/xz.h **************************************/
|
||||
|
||||
/**
|
||||
* xzRet - Return codes
|
||||
* @xzOK: Everything is OK so far. More input or more
|
||||
* output space is required to continue.
|
||||
* @xzStreamEnd: Operation finished successfully.
|
||||
* @xzUnSupportedCheck: Integrity check type is not supported. Decoding
|
||||
* is still possible by simply calling xzDecRun
|
||||
* again.
|
||||
* @xzMemlimitError: A bigger LZMA2 dictionary would be needed than
|
||||
* allowed by the dictMax argument given to
|
||||
* xzDecInit.
|
||||
* @xzFormatError: File format was not recognized (wrong magic
|
||||
* bytes).
|
||||
* @xzOptionsError: This implementation doesn't support the requested
|
||||
* compression options. In the decoder this means
|
||||
* that the header CRC32 matches, but the header
|
||||
* itself specifies something that we don't support.
|
||||
* @xzDataError: Compressed data is corrupt.
|
||||
* @xzBufError: Cannot make any progress.
|
||||
*
|
||||
* xzBufError is returned when two consecutive calls to XZ code cannot
|
||||
* consume any input and cannot produce any new output. This happens
|
||||
* when there is no new input available, or the output buffer is full
|
||||
* while at least one output byte is still pending. Assuming your code
|
||||
* is not buggy, you can get this error only when decoding a
|
||||
* compressed stream that is truncated or otherwise corrupt.
|
||||
*/
|
||||
type xzRet int
|
||||
|
||||
const (
|
||||
xzOK xzRet = iota
|
||||
xzStreamEnd
|
||||
xzUnsupportedCheck
|
||||
xzMemlimitError
|
||||
xzFormatError
|
||||
xzOptionsError
|
||||
xzDataError
|
||||
xzBufError
|
||||
)
|
||||
|
||||
/**
|
||||
* xzBuf - Passing input and output buffers to XZ code
|
||||
* @in: Input buffer.
|
||||
* @inPos: Current position in the input buffer. This must not exceed
|
||||
* input buffer size.
|
||||
* @out: Output buffer.
|
||||
* @outPos: Current position in the output buffer. This must not exceed
|
||||
* output buffer size.
|
||||
*
|
||||
* Only the contents of the output buffer from out[outPos] onward, and
|
||||
* the variables inPos and outPos are modified by the XZ code.
|
||||
*/
|
||||
type xzBuf struct {
|
||||
in []byte
|
||||
inPos int
|
||||
out []byte
|
||||
outPos int
|
||||
}
|
||||
|
||||
/* All XZ filter IDs */
|
||||
type xzFilterID int64
|
||||
|
||||
const (
|
||||
idDelta xzFilterID = 0x03
|
||||
idBCJX86 xzFilterID = 0x04
|
||||
idBCJPowerPC xzFilterID = 0x05
|
||||
idBCJIA64 xzFilterID = 0x06
|
||||
idBCJARM xzFilterID = 0x07
|
||||
idBCJARMThumb xzFilterID = 0x08
|
||||
idBCJSPARC xzFilterID = 0x09
|
||||
idLZMA2 xzFilterID = 0x21
|
||||
)
|
||||
|
||||
// CheckID is the type of the data integrity check in an XZ stream
|
||||
// calculated from the uncompressed data.
|
||||
type CheckID int
|
||||
|
||||
func (id CheckID) String() string {
|
||||
switch id {
|
||||
case CheckNone:
|
||||
return "None"
|
||||
case CheckCRC32:
|
||||
return "CRC32"
|
||||
case CheckCRC64:
|
||||
return "CRC64"
|
||||
case CheckSHA256:
|
||||
return "SHA256"
|
||||
default:
|
||||
return "Unknown"
|
||||
}
|
||||
}
|
||||
|
||||
const (
|
||||
CheckNone CheckID = 0x00
|
||||
CheckCRC32 CheckID = 0x01
|
||||
CheckCRC64 CheckID = 0x04
|
||||
CheckSHA256 CheckID = 0x0A
|
||||
checkMax CheckID = 0x0F
|
||||
checkUnset CheckID = -1
|
||||
)
|
||||
|
||||
// An XZ stream contains a stream header which holds information about
|
||||
// the stream. That information is exposed as fields of the
|
||||
// Reader. Currently it contains only the stream's data integrity
|
||||
// check type.
|
||||
type Header struct {
|
||||
CheckType CheckID // type of the stream's data integrity check
|
||||
}
|
||||
+35
@@ -0,0 +1,35 @@
|
||||
// Package xz implements XZ decompression natively in Go.
|
||||
//
|
||||
// Usage
|
||||
//
|
||||
// For ease of use, this package is designed to have a similar API to
|
||||
// compress/gzip. See the examples for further details.
|
||||
//
|
||||
// Implementation
|
||||
//
|
||||
// This package is a translation from C to Go of XZ Embedded
|
||||
// (http://tukaani.org/xz/embedded.html) with enhancements made so as
|
||||
// to implement all mandatory and optional parts of the XZ file format
|
||||
// specification v1.0.4. It supports all filters and block check
|
||||
// types, supports multiple streams, and performs index verification
|
||||
// using SHA-256 as recommended by the specification.
|
||||
//
|
||||
// Speed
|
||||
//
|
||||
// On the author's Intel Ivybridge i5, decompression speed is about
|
||||
// half that of the standard XZ Utils (tested with a recent linux
|
||||
// kernel tarball).
|
||||
//
|
||||
// Thanks
|
||||
//
|
||||
// Thanks are due to Lasse Collin and Igor Pavlov, the authors of XZ
|
||||
// Embedded, on whose code package xz is based. It would not exist
|
||||
// without their decision to allow others to modify and reuse their
|
||||
// code.
|
||||
//
|
||||
// Bug reports
|
||||
//
|
||||
// For bug reports relating to this package please contact the author
|
||||
// through https://github.com/xi2/xz/issues, and not the authors of XZ
|
||||
// Embedded.
|
||||
package xz
|
||||
+256
@@ -0,0 +1,256 @@
|
||||
/*
|
||||
* Package xz Go Reader API
|
||||
*
|
||||
* Author: Michael Cross <https://github.com/xi2>
|
||||
*
|
||||
* This file has been put into the public domain.
|
||||
* You can do whatever you want with this file.
|
||||
*/
|
||||
|
||||
package xz
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"io"
|
||||
)
|
||||
|
||||
// Package specific errors.
|
||||
var (
|
||||
ErrUnsupportedCheck = errors.New("xz: integrity check type not supported")
|
||||
ErrMemlimit = errors.New("xz: LZMA2 dictionary size exceeds max")
|
||||
ErrFormat = errors.New("xz: file format not recognized")
|
||||
ErrOptions = errors.New("xz: compression options not supported")
|
||||
ErrData = errors.New("xz: data is corrupt")
|
||||
ErrBuf = errors.New("xz: data is truncated or corrupt")
|
||||
)
|
||||
|
||||
// DefaultDictMax is the default maximum dictionary size in bytes used
|
||||
// by the decoder. This value is sufficient to decompress files
|
||||
// created with XZ Utils "xz -9".
|
||||
const DefaultDictMax = 1 << 26 // 64 MiB
|
||||
|
||||
// inBufSize is the input buffer size used by the decoder.
|
||||
const inBufSize = 1 << 13 // 8 KiB
|
||||
|
||||
// A Reader is an io.Reader that can be used to retrieve uncompressed
|
||||
// data from an XZ file.
|
||||
//
|
||||
// In general, an XZ file can be a concatenation of other XZ
|
||||
// files. Reads from the Reader return the concatenation of the
|
||||
// uncompressed data of each.
|
||||
type Reader struct {
|
||||
Header
|
||||
r io.Reader // the wrapped io.Reader
|
||||
multistream bool // true if reader is in multistream mode
|
||||
rEOF bool // true after io.EOF received on r
|
||||
dEOF bool // true after decoder has completed
|
||||
padding int // bytes of stream padding read (or -1)
|
||||
in [inBufSize]byte // backing array for buf.in
|
||||
buf *xzBuf // decoder input/output buffers
|
||||
dec *xzDec // decoder state
|
||||
err error // the result of the last decoder call
|
||||
}
|
||||
|
||||
// NewReader creates a new Reader reading from r. The decompressor
|
||||
// will use an LZMA2 dictionary size up to dictMax bytes in
|
||||
// size. Passing a value of zero sets dictMax to DefaultDictMax. If
|
||||
// an individual XZ stream requires a dictionary size greater than
|
||||
// dictMax in order to decompress, Read will return ErrMemlimit.
|
||||
//
|
||||
// If NewReader is passed a value of nil for r then a Reader is
|
||||
// created such that all read attempts will return io.EOF. This is
|
||||
// useful if you just want to allocate memory for a Reader which will
|
||||
// later be initialized with Reset.
|
||||
//
|
||||
// Due to internal buffering, the Reader may read more data than
|
||||
// necessary from r.
|
||||
func NewReader(r io.Reader, dictMax uint32) (*Reader, error) {
|
||||
if dictMax == 0 {
|
||||
dictMax = DefaultDictMax
|
||||
}
|
||||
z := &Reader{
|
||||
r: r,
|
||||
multistream: true,
|
||||
padding: -1,
|
||||
buf: &xzBuf{},
|
||||
}
|
||||
if r == nil {
|
||||
z.rEOF, z.dEOF = true, true
|
||||
}
|
||||
z.dec = xzDecInit(dictMax, &z.Header)
|
||||
var err error
|
||||
if r != nil {
|
||||
_, err = z.Read(nil) // read stream header
|
||||
}
|
||||
return z, err
|
||||
}
|
||||
|
||||
// decode is a wrapper around xzDecRun that additionally handles
|
||||
// stream padding. It treats the padding as a kind of stream that
|
||||
// decodes to nothing.
|
||||
//
|
||||
// When decoding padding, z.padding >= 0
|
||||
// When decoding a real stream, z.padding == -1
|
||||
func (z *Reader) decode() (ret xzRet) {
|
||||
if z.padding >= 0 {
|
||||
// read all padding in input buffer
|
||||
for z.buf.inPos < len(z.buf.in) &&
|
||||
z.buf.in[z.buf.inPos] == 0 {
|
||||
z.buf.inPos++
|
||||
z.padding++
|
||||
}
|
||||
switch {
|
||||
case z.buf.inPos == len(z.buf.in) && z.rEOF:
|
||||
// case: out of padding. no more input data available
|
||||
if z.padding%4 != 0 {
|
||||
ret = xzDataError
|
||||
} else {
|
||||
ret = xzStreamEnd
|
||||
}
|
||||
case z.buf.inPos == len(z.buf.in):
|
||||
// case: read more padding next loop iteration
|
||||
ret = xzOK
|
||||
default:
|
||||
// case: out of padding. more input data available
|
||||
if z.padding%4 != 0 {
|
||||
ret = xzDataError
|
||||
} else {
|
||||
xzDecReset(z.dec)
|
||||
ret = xzStreamEnd
|
||||
}
|
||||
}
|
||||
} else {
|
||||
ret = xzDecRun(z.dec, z.buf)
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func (z *Reader) Read(p []byte) (n int, err error) {
|
||||
// restore err
|
||||
err = z.err
|
||||
// set decoder output buffer to p
|
||||
z.buf.out = p
|
||||
z.buf.outPos = 0
|
||||
for {
|
||||
// update n
|
||||
n = z.buf.outPos
|
||||
// if last call to decoder ended with an error, return that error
|
||||
if err != nil {
|
||||
break
|
||||
}
|
||||
// if decoder has finished, return with err == io.EOF
|
||||
if z.dEOF {
|
||||
err = io.EOF
|
||||
break
|
||||
}
|
||||
// if p full, return with err == nil, unless we have not yet
|
||||
// read the stream header with Read(nil)
|
||||
if n == len(p) && z.CheckType != checkUnset {
|
||||
break
|
||||
}
|
||||
// if needed, read more data from z.r
|
||||
if z.buf.inPos == len(z.buf.in) && !z.rEOF {
|
||||
rn, e := z.r.Read(z.in[:])
|
||||
if e != nil && e != io.EOF {
|
||||
// read error
|
||||
err = e
|
||||
break
|
||||
}
|
||||
if e == io.EOF {
|
||||
z.rEOF = true
|
||||
}
|
||||
// set new input buffer in z.buf
|
||||
z.buf.in = z.in[:rn]
|
||||
z.buf.inPos = 0
|
||||
}
|
||||
// decode more data
|
||||
ret := z.decode()
|
||||
switch ret {
|
||||
case xzOK:
|
||||
// no action needed
|
||||
case xzStreamEnd:
|
||||
if z.padding >= 0 {
|
||||
z.padding = -1
|
||||
if !z.multistream || z.rEOF {
|
||||
z.dEOF = true
|
||||
}
|
||||
} else {
|
||||
z.padding = 0
|
||||
}
|
||||
case xzUnsupportedCheck:
|
||||
err = ErrUnsupportedCheck
|
||||
case xzMemlimitError:
|
||||
err = ErrMemlimit
|
||||
case xzFormatError:
|
||||
err = ErrFormat
|
||||
case xzOptionsError:
|
||||
err = ErrOptions
|
||||
case xzDataError:
|
||||
err = ErrData
|
||||
case xzBufError:
|
||||
err = ErrBuf
|
||||
}
|
||||
// save err
|
||||
z.err = err
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// Multistream controls whether the reader is operating in multistream
|
||||
// mode.
|
||||
//
|
||||
// If enabled (the default), the Reader expects the input to be a
|
||||
// sequence of XZ streams, possibly interspersed with stream padding,
|
||||
// which it reads one after another. The effect is that the
|
||||
// concatenation of a sequence of XZ streams or XZ files is
|
||||
// treated as equivalent to the compressed result of the concatenation
|
||||
// of the sequence. This is standard behaviour for XZ readers.
|
||||
//
|
||||
// Calling Multistream(false) disables this behaviour; disabling the
|
||||
// behaviour can be useful when reading file formats that distinguish
|
||||
// individual XZ streams. In this mode, when the Reader reaches the
|
||||
// end of the stream, Read returns io.EOF. To start the next stream,
|
||||
// call z.Reset(nil) followed by z.Multistream(false). If there is no
|
||||
// next stream, z.Reset(nil) will return io.EOF.
|
||||
func (z *Reader) Multistream(ok bool) {
|
||||
z.multistream = ok
|
||||
}
|
||||
|
||||
// Reset, for non-nil values of io.Reader r, discards the Reader z's
|
||||
// state and makes it equivalent to the result of its original state
|
||||
// from NewReader, but reading from r instead. This permits reusing a
|
||||
// Reader rather than allocating a new one.
|
||||
//
|
||||
// If you wish to leave r unchanged use z.Reset(nil). This keeps r
|
||||
// unchanged and ensures internal buffering is preserved. If the
|
||||
// Reader was at the end of a stream it is then ready to read any
|
||||
// follow on streams. If there are no follow on streams z.Reset(nil)
|
||||
// returns io.EOF. If the Reader was not at the end of a stream then
|
||||
// z.Reset(nil) does nothing.
|
||||
func (z *Reader) Reset(r io.Reader) error {
|
||||
switch {
|
||||
case r == nil:
|
||||
z.multistream = true
|
||||
if !z.dEOF {
|
||||
return nil
|
||||
}
|
||||
if z.rEOF {
|
||||
return io.EOF
|
||||
}
|
||||
z.dEOF = false
|
||||
_, err := z.Read(nil) // read stream header
|
||||
return err
|
||||
default:
|
||||
z.r = r
|
||||
z.multistream = true
|
||||
z.rEOF = false
|
||||
z.dEOF = false
|
||||
z.padding = -1
|
||||
z.buf.in = nil
|
||||
z.buf.inPos = 0
|
||||
xzDecReset(z.dec)
|
||||
z.err = nil
|
||||
_, err := z.Read(nil) // read stream header
|
||||
return err
|
||||
}
|
||||
}
|
||||
-28
@@ -1,28 +0,0 @@
|
||||
# .gitignore
|
||||
|
||||
TODO.html
|
||||
README.html
|
||||
|
||||
lzma/writer.txt
|
||||
lzma/reader.txt
|
||||
|
||||
cmd/gxz/gxz
|
||||
cmd/xb/xb
|
||||
|
||||
# test executables
|
||||
*.test
|
||||
|
||||
# profile files
|
||||
*.out
|
||||
|
||||
# vim swap file
|
||||
.*.swp
|
||||
|
||||
# executables on windows
|
||||
*.exe
|
||||
|
||||
# default compression test file
|
||||
enwik8*
|
||||
|
||||
# file generated by example
|
||||
example.xz
|
||||
-26
@@ -1,26 +0,0 @@
|
||||
Copyright (c) 2014-2022 Ulrich Kunitz
|
||||
All rights reserved.
|
||||
|
||||
Redistribution and use in source and binary forms, with or without
|
||||
modification, are permitted provided that the following conditions are met:
|
||||
|
||||
* Redistributions of source code must retain the above copyright notice, this
|
||||
list of conditions and the following disclaimer.
|
||||
|
||||
* Redistributions in binary form must reproduce the above copyright notice,
|
||||
this list of conditions and the following disclaimer in the documentation
|
||||
and/or other materials provided with the distribution.
|
||||
|
||||
* My name, Ulrich Kunitz, may not be used to endorse or promote products
|
||||
derived from this software without specific prior written permission.
|
||||
|
||||
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||||
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
||||
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||||
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
||||
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||||
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
-88
@@ -1,88 +0,0 @@
|
||||
# Package xz
|
||||
|
||||
This Go language package supports the reading and writing of xz
|
||||
compressed streams. It includes also a gxz command for compressing and
|
||||
decompressing data. The package is completely written in Go and doesn't
|
||||
have any dependency on any C code.
|
||||
|
||||
The package is currently under development. There might be bugs and APIs
|
||||
are not considered stable. At this time the package cannot compete with
|
||||
the xz tool regarding compression speed and size. The algorithms there
|
||||
have been developed over a long time and are highly optimized. However
|
||||
there are a number of improvements planned and I'm very optimistic about
|
||||
parallel compression and decompression. Stay tuned!
|
||||
|
||||
## Using the API
|
||||
|
||||
The following example program shows how to use the API.
|
||||
|
||||
```go
|
||||
package main
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"io"
|
||||
"log"
|
||||
"os"
|
||||
|
||||
"github.com/ulikunitz/xz"
|
||||
)
|
||||
|
||||
func main() {
|
||||
const text = "The quick brown fox jumps over the lazy dog.\n"
|
||||
var buf bytes.Buffer
|
||||
// compress text
|
||||
w, err := xz.NewWriter(&buf)
|
||||
if err != nil {
|
||||
log.Fatalf("xz.NewWriter error %s", err)
|
||||
}
|
||||
if _, err := io.WriteString(w, text); err != nil {
|
||||
log.Fatalf("WriteString error %s", err)
|
||||
}
|
||||
if err := w.Close(); err != nil {
|
||||
log.Fatalf("w.Close error %s", err)
|
||||
}
|
||||
// decompress buffer and write output to stdout
|
||||
r, err := xz.NewReader(&buf)
|
||||
if err != nil {
|
||||
log.Fatalf("NewReader error %s", err)
|
||||
}
|
||||
if _, err = io.Copy(os.Stdout, r); err != nil {
|
||||
log.Fatalf("io.Copy error %s", err)
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
## Documentation
|
||||
|
||||
You can find the full documentation at [pkg.go.dev](https://pkg.go.dev/github.com/ulikunitz/xz).
|
||||
|
||||
## Using the gxz compression tool
|
||||
|
||||
The package includes a gxz command line utility for compression and
|
||||
decompression.
|
||||
|
||||
Use following command for installation:
|
||||
|
||||
$ go get github.com/ulikunitz/xz/cmd/gxz
|
||||
|
||||
To test it call the following command.
|
||||
|
||||
$ gxz bigfile
|
||||
|
||||
After some time a much smaller file bigfile.xz will replace bigfile.
|
||||
To decompress it use the following command.
|
||||
|
||||
$ gxz -d bigfile.xz
|
||||
|
||||
## Security & Vulnerabilities
|
||||
|
||||
The security policy is documented in [SECURITY.md](SECURITY.md).
|
||||
|
||||
The software is not affected by the supply chain attack on the original xz
|
||||
implementation, [CVE-2024-3094](https://nvd.nist.gov/vuln/detail/CVE-2024-3094).
|
||||
This implementation doesn't share any files with the original xz implementation
|
||||
and no patches or pull requests are accepted without a review.
|
||||
|
||||
All security advisories for this project are published under
|
||||
[github.com/ulikunitz/xz/security/advisories](https://github.com/ulikunitz/xz/security/advisories?state=published).
|
||||
-19
@@ -1,19 +0,0 @@
|
||||
# Security Policy
|
||||
|
||||
## Supported Versions
|
||||
|
||||
Currently the last minor version v0.5.x is supported.
|
||||
|
||||
## Reporting a Vulnerability
|
||||
|
||||
You can privately report a vulnerability following this
|
||||
[procedure](https://docs.github.com/en/code-security/security-advisories/guidance-on-reporting-and-writing-information-about-vulnerabilities/privately-reporting-a-security-vulnerability#privately-reporting-a-security-vulnerability).
|
||||
Alternatively you can create a Github issue at
|
||||
<https://github.com/ulikunitz/xz/issues>.
|
||||
|
||||
In both cases expect a response in at least 7 days.
|
||||
|
||||
## Security Advisories
|
||||
|
||||
All security advisories for this project are published under
|
||||
[github.com/ulikunitz/xz/security/advisories](https://github.com/ulikunitz/xz/security/advisories?state=published).
|
||||
-395
@@ -1,395 +0,0 @@
|
||||
# TODO list
|
||||
|
||||
## Release v0.6
|
||||
|
||||
1. Review encoder and check for lzma improvements under xz.
|
||||
2. Fix binary tree matcher.
|
||||
3. Compare compression ratio with xz tool using comparable parameters and optimize parameters
|
||||
4. rename operation action and make it a simple type of size 8
|
||||
5. make maxMatches, wordSize parameters
|
||||
6. stop searching after a certain length is found (parameter sweetLen)
|
||||
|
||||
## Release v0.7
|
||||
|
||||
1. Optimize code
|
||||
2. Do statistical analysis to get linear presets.
|
||||
3. Test sync.Pool compatability for xz and lzma Writer and Reader
|
||||
4. Fuzz optimized code.
|
||||
|
||||
## Release v0.8
|
||||
|
||||
1. Support parallel go routines for writing and reading xz files.
|
||||
2. Support a ReaderAt interface for xz files with small block sizes.
|
||||
3. Improve compatibility between gxz and xz
|
||||
4. Provide manual page for gxz
|
||||
|
||||
## Release v0.9
|
||||
|
||||
1. Improve documentation
|
||||
2. Fuzz again
|
||||
|
||||
## Release v1.0
|
||||
|
||||
1. Full functioning gxz
|
||||
2. Add godoc URL to README.md (godoc.org)
|
||||
3. Resolve all issues.
|
||||
4. Define release candidates.
|
||||
5. Public announcement.
|
||||
|
||||
## Package lzma
|
||||
|
||||
### v0.6
|
||||
|
||||
* Rewrite Encoder into a simple greedy one-op-at-a-time encoder including
|
||||
* simple scan at the dictionary head for the same byte
|
||||
* use the killer byte (requiring matches to get longer, the first test should be the byte that would make the match longer)
|
||||
|
||||
## Optimizations
|
||||
|
||||
* There may be a lot of false sharing in lzma. State; check whether this can be improved by reorganizing the internal structure of it.
|
||||
|
||||
* Check whether batching encoding and decoding improves speed.
|
||||
|
||||
### DAG optimizations
|
||||
|
||||
* Use full buffer to create minimal bit-length above range encoder.
|
||||
* Might be too slow (see v0.4)
|
||||
|
||||
### Different match finders
|
||||
|
||||
* hashes with 2, 3 characters additional to 4 characters
|
||||
* binary trees with 2-7 characters (uint64 as key, use uint32 as
|
||||
|
||||
pointers into a an array)
|
||||
|
||||
* rb-trees with 2-7 characters (uint64 as key, use uint32 as pointers
|
||||
|
||||
into an array with bit-steeling for the colors)
|
||||
|
||||
## Release Procedure
|
||||
|
||||
* execute goch -l for all packages; probably with lower param like 0.5.
|
||||
* check orthography with gospell
|
||||
* Write release notes in doc/relnotes.
|
||||
* Update README.md
|
||||
* xb copyright . in xz directory to ensure all new files have Copyright header
|
||||
* `VERSION=<version> go generate github.com/ulikunitz/xz/...` to update version files
|
||||
* Execute [test for Linux/amd64, Linux/x86 and Windows/amd64](.github/workflows/go-test-platforms.yml).
|
||||
* Update TODO.md - write short log entry
|
||||
* `git checkout master && git merge dev`
|
||||
* `git tag -a <version>`
|
||||
* `git push`
|
||||
|
||||
## Log
|
||||
|
||||
## 2026-09-19
|
||||
|
||||
Includes a fix for lzma.breader handling 0, nil Reader returns correctly.
|
||||
|
||||
## 2026-07-20
|
||||
|
||||
New release v0.5.16 to support other operating systems like Illumos using a
|
||||
simple fallback function for IsTerminal to avoid adding a dependency.
|
||||
|
||||
## 2025-08-28
|
||||
|
||||
Release v0.5.14 addresses the security vulnerability CVE-2025-58058. If you put
|
||||
bytes in from of a LZMA stream, the header might not be read correctly and
|
||||
memory for the dictionary buffer allocated. I have implemented mitigations for
|
||||
the problem.
|
||||
|
||||
### 2025-08-20
|
||||
|
||||
Release v0.5.13 addressed issue #61 regarding handling of multiple WriteClosers
|
||||
together. So I added a new package xio with a WriteCloserStack to address the
|
||||
issue.
|
||||
|
||||
### 2024-04-03
|
||||
|
||||
Release v0.5.12 updates README.md and SECURITY.md to address the supply chain
|
||||
attack on the original xz implementation.
|
||||
|
||||
### 2022-12-12
|
||||
|
||||
Matt Dantay (@bodgit) reported an issue with the LZMA reader. The implementation
|
||||
returned an error if the dictionary size was less than 4096 byte, but the
|
||||
recommendation stated the actual used window size should be set to 4096 byte in
|
||||
that case. It actually was the pull request
|
||||
[#52](https://github.com/ulikunitz/xz/pull/52). The new patch v0.5.11 will fix
|
||||
it.
|
||||
|
||||
### 2021-02-02
|
||||
|
||||
Mituo Heijo has fuzzed xz and found a bug in the function readIndexBody. The
|
||||
function allocated a slice of records immediately after reading the value
|
||||
without further checks. Since the number has been too large the make function
|
||||
did panic. The fix is to check the number against the expected number of records
|
||||
before allocating the records.
|
||||
|
||||
### 2020-12-17
|
||||
|
||||
Release v0.5.9 fixes warnings, a typo and adds SECURITY.md.
|
||||
|
||||
One fix is interesting.
|
||||
|
||||
```go
|
||||
const (
|
||||
a byte = 0x1
|
||||
b = 0x2
|
||||
)
|
||||
```
|
||||
|
||||
The constants a and b don't have the same type. Correct is
|
||||
|
||||
```go
|
||||
const (
|
||||
a byte = 0x1
|
||||
b byte = 0x2
|
||||
)
|
||||
```
|
||||
|
||||
### 2020-08-19
|
||||
|
||||
Release v0.5.8 fixes issue
|
||||
[issue #35](https://github.com/ulikunitz/xz/issues/35).
|
||||
|
||||
### 2020-02-24
|
||||
|
||||
Release v0.5.7 supports the check-ID None and fixes
|
||||
[issue #27](https://github.com/ulikunitz/xz/issues/27).
|
||||
|
||||
### 2019-02-20
|
||||
|
||||
Release v0.5.6 supports the go.mod file.
|
||||
|
||||
### 2018-10-28
|
||||
|
||||
Release v0.5.5 fixes issues #19 observing ErrLimit outputs.
|
||||
|
||||
### 2017-06-05
|
||||
|
||||
Release v0.5.4 fixes issues #15 of another problem with the padding size
|
||||
check for the xz block header. I removed the check completely.
|
||||
|
||||
### 2017-02-15
|
||||
|
||||
Release v0.5.3 fixes issue #12 regarding the decompression of an empty
|
||||
XZ stream. Many thanks to Tomasz Kłak, who reported the issue.
|
||||
|
||||
### 2016-12-02
|
||||
|
||||
Release v0.5.2 became necessary to allow the decoding of xz files with
|
||||
4-byte padding in the block header. Many thanks to Greg, who reported
|
||||
the issue.
|
||||
|
||||
### 2016-07-23
|
||||
|
||||
Release v0.5.1 became necessary to fix problems with 32-bit platforms.
|
||||
Many thanks to Bruno Brigas, who reported the issue.
|
||||
|
||||
### 2016-07-04
|
||||
|
||||
Release v0.5 provides improvements to the compressor and provides support for
|
||||
the decompression of xz files with multiple xz streams.
|
||||
|
||||
### 2016-01-31
|
||||
|
||||
Another compression rate increase by checking the byte at length of the
|
||||
best match first, before checking the whole prefix. This makes the
|
||||
compressor even faster. We have now a large time budget to beat the
|
||||
compression ratio of the xz tool. For enwik8 we have now over 40 seconds
|
||||
to reduce the compressed file size for another 7 MiB.
|
||||
|
||||
### 2016-01-30
|
||||
|
||||
I simplified the encoder. Speed and compression rate increased
|
||||
dramatically. A high compression rate affects also the decompression
|
||||
speed. The approach with the buffer and optimizing for operation
|
||||
compression rate has not been successful. Going for the maximum length
|
||||
appears to be the best approach.
|
||||
|
||||
### 2016-01-28
|
||||
|
||||
The release v0.4 is ready. It provides a working xz implementation,
|
||||
which is rather slow, but works and is interoperable with the xz tool.
|
||||
It is an important milestone.
|
||||
|
||||
### 2016-01-10
|
||||
|
||||
I have the first working implementation of an xz reader and writer. I'm
|
||||
happy about reaching this milestone.
|
||||
|
||||
### 2015-12-02
|
||||
|
||||
I'm now ready to implement xz because, I have a working LZMA2
|
||||
implementation. I decided today that v0.4 will use the slow encoder
|
||||
using the operations buffer to be able to go back, if I intend to do so.
|
||||
|
||||
### 2015-10-21
|
||||
|
||||
I have restarted the work on the library. While trying to implement
|
||||
LZMA2, I discovered that I need to resimplify the encoder and decoder
|
||||
functions. The option approach is too complicated. Using a limited byte
|
||||
writer and not caring for written bytes at all and not to try to handle
|
||||
uncompressed data simplifies the LZMA encoder and decoder much.
|
||||
Processing uncompressed data and handling limits is a feature of the
|
||||
LZMA2 format not of LZMA.
|
||||
|
||||
I learned an interesting method from the LZO format. If the last copy is
|
||||
too far away they are moving the head one 2 bytes and not 1 byte to
|
||||
reduce processing times.
|
||||
|
||||
### 2015-08-26
|
||||
|
||||
I have now reimplemented the lzma package. The code is reasonably fast,
|
||||
but can still be optimized. The next step is to implement LZMA2 and then
|
||||
xz.
|
||||
|
||||
### 2015-07-05
|
||||
|
||||
Created release v0.3. The version is the foundation for a full xz
|
||||
implementation that is the target of v0.4.
|
||||
|
||||
### 2015-06-11
|
||||
|
||||
The gflag package has been developed because I couldn't use flag and
|
||||
pflag for a fully compatible support of gzip's and lzma's options. It
|
||||
seems to work now quite nicely.
|
||||
|
||||
### 2015-06-05
|
||||
|
||||
The overflow issue was interesting to research, however Henry S. Warren
|
||||
Jr. Hacker's Delight book was very helpful as usual and had the issue
|
||||
explained perfectly. Fefe's information on his website was based on the
|
||||
C FAQ and quite bad, because it didn't address the issue of -MININT ==
|
||||
MININT.
|
||||
|
||||
### 2015-06-04
|
||||
|
||||
It has been a productive day. I improved the interface of lzma. Reader
|
||||
and lzma. Writer and fixed the error handling.
|
||||
|
||||
### 2015-06-01
|
||||
|
||||
By computing the bit length of the LZMA operations I was able to
|
||||
improve the greedy algorithm implementation. By using an 8 MByte buffer
|
||||
the compression rate was not as good as for xz but already better then
|
||||
gzip default.
|
||||
|
||||
Compression is currently slow, but this is something we will be able to
|
||||
improve over time.
|
||||
|
||||
### 2015-05-26
|
||||
|
||||
Checked the license of ogier/pflag. The binary lzmago binary should
|
||||
include the license terms for the pflag library.
|
||||
|
||||
I added the endorsement clause as used by Google for the Go sources the
|
||||
LICENSE file.
|
||||
|
||||
### 2015-05-22
|
||||
|
||||
The package lzb contains now the basic implementation for creating or
|
||||
reading LZMA byte streams. It allows the support for the implementation
|
||||
of the DAG-shortest-path algorithm for the compression function.
|
||||
|
||||
### 2015-04-23
|
||||
|
||||
Completed yesterday the lzbase classes. I'm a little bit concerned that
|
||||
using the components may require too much code, but on the other hand
|
||||
there is a lot of flexibility.
|
||||
|
||||
### 2015-04-22
|
||||
|
||||
Implemented Reader and Writer during the Bayern game against Porto. The
|
||||
second half gave me enough time.
|
||||
|
||||
### 2015-04-21
|
||||
|
||||
While showering today morning I discovered that the design for OpEncoder
|
||||
and OpDecoder doesn't work, because encoding/decoding might depend on
|
||||
the current status of the dictionary. This is not exactly the right way
|
||||
to start the day.
|
||||
|
||||
Therefore we need to keep the Reader and Writer design. This time around
|
||||
we simplify it by ignoring size limits. These can be added by wrappers
|
||||
around the Reader and Writer interfaces. The Parameters type isn't
|
||||
needed anymore.
|
||||
|
||||
However I will implement a ReaderState and WriterState type to use
|
||||
static typing to ensure the right State object is combined with the
|
||||
right lzbase. Reader and lzbase. Writer.
|
||||
|
||||
As a start I have implemented ReaderState and WriterState to ensure
|
||||
that the state for reading is only used by readers and WriterState only
|
||||
used by Writers.
|
||||
|
||||
### 2015-04-20
|
||||
|
||||
Today I implemented the OpDecoder and tested OpEncoder and OpDecoder.
|
||||
|
||||
### 2015-04-08
|
||||
|
||||
Came up with a new simplified design for lzbase. I implemented already
|
||||
the type State that replaces OpCodec.
|
||||
|
||||
### 2015-04-06
|
||||
|
||||
The new lzma package is now fully usable and lzmago is using it now. The
|
||||
old lzma package has been completely removed.
|
||||
|
||||
### 2015-04-05
|
||||
|
||||
Implemented lzma. Reader and tested it.
|
||||
|
||||
### 2015-04-04
|
||||
|
||||
Implemented baseReader by adapting code form lzma. Reader.
|
||||
|
||||
### 2015-04-03
|
||||
|
||||
The opCodec has been copied yesterday to lzma2. opCodec has a high
|
||||
number of dependencies on other files in lzma2. Therefore I had to copy
|
||||
almost all files from lzma.
|
||||
|
||||
### 2015-03-31
|
||||
|
||||
Removed only a TODO item.
|
||||
|
||||
However in Francesco Campoy's presentation "Go for Javaneros
|
||||
(Javaïstes?)" is the the idea that using an embedded field E, all the
|
||||
methods of E will be defined on T. If E is an interface T satisfies E.
|
||||
|
||||
<https://talks.golang.org/2014/go4java.slide#51>
|
||||
|
||||
I have never used this, but it seems to be a cool idea.
|
||||
|
||||
### 2015-03-30
|
||||
|
||||
Finished the type writerDict and wrote a simple test.
|
||||
|
||||
### 2015-03-25
|
||||
|
||||
I started to implement the writerDict.
|
||||
|
||||
### 2015-03-24
|
||||
|
||||
After thinking long about the LZMA2 code and several false starts, I
|
||||
have now a plan to create a self-sufficient lzma2 package that supports
|
||||
the classic LZMA format as well as LZMA2. The core idea is to support a
|
||||
baseReader and baseWriter type that support the basic LZMA stream
|
||||
without any headers. Both types must support the reuse of dictionaries
|
||||
and the opCodec.
|
||||
|
||||
### 2015-01-10
|
||||
|
||||
1. Implemented simple lzmago tool
|
||||
2. Tested tool against large 4.4G file
|
||||
* compression worked correctly; tested decompression with lzma
|
||||
* decompression hits a full buffer condition
|
||||
3. Fixed a bug in the compressor and wrote a test for it
|
||||
4. Executed full cycle for 4.4 GB file; performance can be improved ;-)
|
||||
|
||||
### 2015-01-11
|
||||
|
||||
* Release v0.2 because of the working LZMA encoder and decoder
|
||||
-79
@@ -1,79 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"io"
|
||||
)
|
||||
|
||||
// putUint32LE puts the little-endian representation of x into the first
|
||||
// four bytes of p.
|
||||
func putUint32LE(p []byte, x uint32) {
|
||||
p[0] = byte(x)
|
||||
p[1] = byte(x >> 8)
|
||||
p[2] = byte(x >> 16)
|
||||
p[3] = byte(x >> 24)
|
||||
}
|
||||
|
||||
// putUint64LE puts the little-endian representation of x into the first
|
||||
// eight bytes of p.
|
||||
func putUint64LE(p []byte, x uint64) {
|
||||
p[0] = byte(x)
|
||||
p[1] = byte(x >> 8)
|
||||
p[2] = byte(x >> 16)
|
||||
p[3] = byte(x >> 24)
|
||||
p[4] = byte(x >> 32)
|
||||
p[5] = byte(x >> 40)
|
||||
p[6] = byte(x >> 48)
|
||||
p[7] = byte(x >> 56)
|
||||
}
|
||||
|
||||
// uint32LE converts a little endian representation to an uint32 value.
|
||||
func uint32LE(p []byte) uint32 {
|
||||
return uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 |
|
||||
uint32(p[3])<<24
|
||||
}
|
||||
|
||||
// putUvarint puts a uvarint representation of x into the byte slice.
|
||||
func putUvarint(p []byte, x uint64) int {
|
||||
i := 0
|
||||
for x >= 0x80 {
|
||||
p[i] = byte(x) | 0x80
|
||||
x >>= 7
|
||||
i++
|
||||
}
|
||||
p[i] = byte(x)
|
||||
return i + 1
|
||||
}
|
||||
|
||||
// errOverflow indicates an overflow of the 64-bit unsigned integer.
|
||||
var errOverflowU64 = errors.New("xz: uvarint overflows 64-bit unsigned integer")
|
||||
|
||||
// readUvarint reads a uvarint from the given byte reader.
|
||||
func readUvarint(r io.ByteReader) (x uint64, n int, err error) {
|
||||
const maxUvarintLen = 10
|
||||
|
||||
var s uint
|
||||
i := 0
|
||||
for {
|
||||
b, err := r.ReadByte()
|
||||
if err != nil {
|
||||
return x, i, err
|
||||
}
|
||||
i++
|
||||
if i > maxUvarintLen {
|
||||
return x, i, errOverflowU64
|
||||
}
|
||||
if b < 0x80 {
|
||||
if i == maxUvarintLen && b > 1 {
|
||||
return x, i, errOverflowU64
|
||||
}
|
||||
return x | uint64(b)<<s, i, nil
|
||||
}
|
||||
x |= uint64(b&0x7f) << s
|
||||
s += 7
|
||||
}
|
||||
}
|
||||
-54
@@ -1,54 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import (
|
||||
"hash"
|
||||
"hash/crc32"
|
||||
"hash/crc64"
|
||||
)
|
||||
|
||||
// crc32Hash implements the hash.Hash32 interface with Sum returning the
|
||||
// crc32 value in little-endian encoding.
|
||||
type crc32Hash struct {
|
||||
hash.Hash32
|
||||
}
|
||||
|
||||
// Sum returns the crc32 value as little endian.
|
||||
func (h crc32Hash) Sum(b []byte) []byte {
|
||||
p := make([]byte, 4)
|
||||
putUint32LE(p, h.Hash32.Sum32())
|
||||
b = append(b, p...)
|
||||
return b
|
||||
}
|
||||
|
||||
// newCRC32 returns a CRC-32 hash that returns the 64-bit value in
|
||||
// little-endian encoding using the IEEE polynomial.
|
||||
func newCRC32() hash.Hash {
|
||||
return crc32Hash{Hash32: crc32.NewIEEE()}
|
||||
}
|
||||
|
||||
// crc64Hash implements the Hash64 interface with Sum returning the
|
||||
// CRC-64 value in little-endian encoding.
|
||||
type crc64Hash struct {
|
||||
hash.Hash64
|
||||
}
|
||||
|
||||
// Sum returns the CRC-64 value in little-endian encoding.
|
||||
func (h crc64Hash) Sum(b []byte) []byte {
|
||||
p := make([]byte, 8)
|
||||
putUint64LE(p, h.Hash64.Sum64())
|
||||
b = append(b, p...)
|
||||
return b
|
||||
}
|
||||
|
||||
// crc64Table is used to create a CRC-64 hash.
|
||||
var crc64Table = crc64.MakeTable(crc64.ECMA)
|
||||
|
||||
// newCRC64 returns a CRC-64 hash that returns the 64-bit value in
|
||||
// little-endian encoding using the ECMA polynomial.
|
||||
func newCRC64() hash.Hash {
|
||||
return crc64Hash{Hash64: crc64.New(crc64Table)}
|
||||
}
|
||||
-721
@@ -1,721 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/sha256"
|
||||
"errors"
|
||||
"fmt"
|
||||
"hash"
|
||||
"hash/crc32"
|
||||
"io"
|
||||
|
||||
"github.com/ulikunitz/xz/lzma"
|
||||
)
|
||||
|
||||
// allZeros checks whether a given byte slice has only zeros.
|
||||
func allZeros(p []byte) bool {
|
||||
for _, c := range p {
|
||||
if c != 0 {
|
||||
return false
|
||||
}
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
// padLen returns the length of the padding required for the given
|
||||
// argument.
|
||||
func padLen(n int64) int {
|
||||
k := int(n % 4)
|
||||
if k > 0 {
|
||||
k = 4 - k
|
||||
}
|
||||
return k
|
||||
}
|
||||
|
||||
/*** Header ***/
|
||||
|
||||
// headerMagic stores the magic bytes for the header
|
||||
var headerMagic = []byte{0xfd, '7', 'z', 'X', 'Z', 0x00}
|
||||
|
||||
// HeaderLen provides the length of the xz file header.
|
||||
const HeaderLen = 12
|
||||
|
||||
// Constants for the checksum methods supported by xz.
|
||||
const (
|
||||
None byte = 0x0
|
||||
CRC32 byte = 0x1
|
||||
CRC64 byte = 0x4
|
||||
SHA256 byte = 0xa
|
||||
)
|
||||
|
||||
// errInvalidFlags indicates that flags are invalid.
|
||||
var errInvalidFlags = errors.New("xz: invalid flags")
|
||||
|
||||
// verifyFlags returns the error errInvalidFlags if the value is
|
||||
// invalid.
|
||||
func verifyFlags(flags byte) error {
|
||||
switch flags {
|
||||
case None, CRC32, CRC64, SHA256:
|
||||
return nil
|
||||
default:
|
||||
return errInvalidFlags
|
||||
}
|
||||
}
|
||||
|
||||
// flagstrings maps flag values to strings.
|
||||
var flagstrings = map[byte]string{
|
||||
None: "None",
|
||||
CRC32: "CRC-32",
|
||||
CRC64: "CRC-64",
|
||||
SHA256: "SHA-256",
|
||||
}
|
||||
|
||||
// flagString returns the string representation for the given flags.
|
||||
func flagString(flags byte) string {
|
||||
s, ok := flagstrings[flags]
|
||||
if !ok {
|
||||
return "invalid"
|
||||
}
|
||||
return s
|
||||
}
|
||||
|
||||
// newHashFunc returns a function that creates hash instances for the
|
||||
// hash method encoded in flags.
|
||||
func newHashFunc(flags byte) (newHash func() hash.Hash, err error) {
|
||||
switch flags {
|
||||
case None:
|
||||
newHash = newNoneHash
|
||||
case CRC32:
|
||||
newHash = newCRC32
|
||||
case CRC64:
|
||||
newHash = newCRC64
|
||||
case SHA256:
|
||||
newHash = sha256.New
|
||||
default:
|
||||
err = errInvalidFlags
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// header provides the actual content of the xz file header: the flags.
|
||||
type header struct {
|
||||
flags byte
|
||||
}
|
||||
|
||||
// Errors returned by readHeader.
|
||||
var errHeaderMagic = errors.New("xz: invalid header magic bytes")
|
||||
|
||||
// ValidHeader checks whether data is a correct xz file header. The
|
||||
// length of data must be HeaderLen.
|
||||
func ValidHeader(data []byte) bool {
|
||||
var h header
|
||||
err := h.UnmarshalBinary(data)
|
||||
return err == nil
|
||||
}
|
||||
|
||||
// String returns a string representation of the flags.
|
||||
func (h header) String() string {
|
||||
return flagString(h.flags)
|
||||
}
|
||||
|
||||
// UnmarshalBinary reads header from the provided data slice.
|
||||
func (h *header) UnmarshalBinary(data []byte) error {
|
||||
// header length
|
||||
if len(data) != HeaderLen {
|
||||
return errors.New("xz: wrong file header length")
|
||||
}
|
||||
|
||||
// magic header
|
||||
if !bytes.Equal(headerMagic, data[:6]) {
|
||||
return errHeaderMagic
|
||||
}
|
||||
|
||||
// checksum
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[6:8])
|
||||
if uint32LE(data[8:]) != crc.Sum32() {
|
||||
return errors.New("xz: invalid checksum for file header")
|
||||
}
|
||||
|
||||
// stream flags
|
||||
if data[6] != 0 {
|
||||
return errInvalidFlags
|
||||
}
|
||||
flags := data[7]
|
||||
if err := verifyFlags(flags); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
h.flags = flags
|
||||
return nil
|
||||
}
|
||||
|
||||
// MarshalBinary generates the xz file header.
|
||||
func (h *header) MarshalBinary() (data []byte, err error) {
|
||||
if err = verifyFlags(h.flags); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
data = make([]byte, 12)
|
||||
copy(data, headerMagic)
|
||||
data[7] = h.flags
|
||||
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[6:8])
|
||||
putUint32LE(data[8:], crc.Sum32())
|
||||
|
||||
return data, nil
|
||||
}
|
||||
|
||||
/*** Footer ***/
|
||||
|
||||
// footerLen defines the length of the footer.
|
||||
const footerLen = 12
|
||||
|
||||
// footerMagic contains the footer magic bytes.
|
||||
var footerMagic = []byte{'Y', 'Z'}
|
||||
|
||||
// footer represents the content of the xz file footer.
|
||||
type footer struct {
|
||||
indexSize int64
|
||||
flags byte
|
||||
}
|
||||
|
||||
// String prints a string representation of the footer structure.
|
||||
func (f footer) String() string {
|
||||
return fmt.Sprintf("%s index size %d", flagString(f.flags), f.indexSize)
|
||||
}
|
||||
|
||||
// Minimum and maximum for the size of the index (backward size).
|
||||
const (
|
||||
minIndexSize = 4
|
||||
maxIndexSize = (1 << 32) * 4
|
||||
)
|
||||
|
||||
// MarshalBinary converts footer values into an xz file footer. Note
|
||||
// that the footer value is checked for correctness.
|
||||
func (f *footer) MarshalBinary() (data []byte, err error) {
|
||||
if err = verifyFlags(f.flags); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if !(minIndexSize <= f.indexSize && f.indexSize <= maxIndexSize) {
|
||||
return nil, errors.New("xz: index size out of range")
|
||||
}
|
||||
if f.indexSize%4 != 0 {
|
||||
return nil, errors.New(
|
||||
"xz: index size not aligned to four bytes")
|
||||
}
|
||||
|
||||
data = make([]byte, footerLen)
|
||||
|
||||
// backward size (index size)
|
||||
s := (f.indexSize / 4) - 1
|
||||
putUint32LE(data[4:], uint32(s))
|
||||
// flags
|
||||
data[9] = f.flags
|
||||
// footer magic
|
||||
copy(data[10:], footerMagic)
|
||||
|
||||
// CRC-32
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[4:10])
|
||||
putUint32LE(data, crc.Sum32())
|
||||
|
||||
return data, nil
|
||||
}
|
||||
|
||||
// UnmarshalBinary sets the footer value by unmarshalling an xz file
|
||||
// footer.
|
||||
func (f *footer) UnmarshalBinary(data []byte) error {
|
||||
if len(data) != footerLen {
|
||||
return errors.New("xz: wrong footer length")
|
||||
}
|
||||
|
||||
// magic bytes
|
||||
if !bytes.Equal(data[10:], footerMagic) {
|
||||
return errors.New("xz: footer magic invalid")
|
||||
}
|
||||
|
||||
// CRC-32
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[4:10])
|
||||
if uint32LE(data) != crc.Sum32() {
|
||||
return errors.New("xz: footer checksum error")
|
||||
}
|
||||
|
||||
var g footer
|
||||
// backward size (index size)
|
||||
g.indexSize = (int64(uint32LE(data[4:])) + 1) * 4
|
||||
|
||||
// flags
|
||||
if data[8] != 0 {
|
||||
return errInvalidFlags
|
||||
}
|
||||
g.flags = data[9]
|
||||
if err := verifyFlags(g.flags); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
*f = g
|
||||
return nil
|
||||
}
|
||||
|
||||
/*** Block Header ***/
|
||||
|
||||
// blockHeader represents the content of an xz block header.
|
||||
type blockHeader struct {
|
||||
compressedSize int64
|
||||
uncompressedSize int64
|
||||
filters []filter
|
||||
}
|
||||
|
||||
// String converts the block header into a string.
|
||||
func (h blockHeader) String() string {
|
||||
var buf bytes.Buffer
|
||||
first := true
|
||||
if h.compressedSize >= 0 {
|
||||
fmt.Fprintf(&buf, "compressed size %d", h.compressedSize)
|
||||
first = false
|
||||
}
|
||||
if h.uncompressedSize >= 0 {
|
||||
if !first {
|
||||
buf.WriteString(" ")
|
||||
}
|
||||
fmt.Fprintf(&buf, "uncompressed size %d", h.uncompressedSize)
|
||||
first = false
|
||||
}
|
||||
for _, f := range h.filters {
|
||||
if !first {
|
||||
buf.WriteString(" ")
|
||||
}
|
||||
fmt.Fprintf(&buf, "filter %s", f)
|
||||
first = false
|
||||
}
|
||||
return buf.String()
|
||||
}
|
||||
|
||||
// Masks for the block flags.
|
||||
const (
|
||||
filterCountMask = 0x03
|
||||
compressedSizePresent = 0x40
|
||||
uncompressedSizePresent = 0x80
|
||||
reservedBlockFlags = 0x3C
|
||||
)
|
||||
|
||||
// errIndexIndicator signals that an index indicator (0x00) has been found
|
||||
// instead of an expected block header indicator.
|
||||
var errIndexIndicator = errors.New("xz: found index indicator")
|
||||
|
||||
// readBlockHeader reads the block header.
|
||||
func readBlockHeader(r io.Reader) (h *blockHeader, n int, err error) {
|
||||
var buf bytes.Buffer
|
||||
buf.Grow(20)
|
||||
|
||||
// block header size
|
||||
z, err := io.CopyN(&buf, r, 1)
|
||||
n = int(z)
|
||||
if err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
s := buf.Bytes()[0]
|
||||
if s == 0 {
|
||||
return nil, n, errIndexIndicator
|
||||
}
|
||||
|
||||
// read complete header
|
||||
headerLen := (int(s) + 1) * 4
|
||||
buf.Grow(headerLen - 1)
|
||||
z, err = io.CopyN(&buf, r, int64(headerLen-1))
|
||||
n += int(z)
|
||||
if err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
|
||||
// unmarshal block header
|
||||
h = new(blockHeader)
|
||||
if err = h.UnmarshalBinary(buf.Bytes()); err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
|
||||
return h, n, nil
|
||||
}
|
||||
|
||||
// readSizeInBlockHeader reads the uncompressed or compressed size
|
||||
// fields in the block header. The present value informs the function
|
||||
// whether the respective field is actually present in the header.
|
||||
func readSizeInBlockHeader(r io.ByteReader, present bool) (n int64, err error) {
|
||||
if !present {
|
||||
return -1, nil
|
||||
}
|
||||
x, _, err := readUvarint(r)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
if x >= 1<<63 {
|
||||
return 0, errors.New("xz: size overflow in block header")
|
||||
}
|
||||
return int64(x), nil
|
||||
}
|
||||
|
||||
// UnmarshalBinary unmarshals the block header.
|
||||
func (h *blockHeader) UnmarshalBinary(data []byte) error {
|
||||
// Check header length
|
||||
s := data[0]
|
||||
if data[0] == 0 {
|
||||
return errIndexIndicator
|
||||
}
|
||||
headerLen := (int(s) + 1) * 4
|
||||
if len(data) != headerLen {
|
||||
return fmt.Errorf("xz: data length %d; want %d", len(data),
|
||||
headerLen)
|
||||
}
|
||||
n := headerLen - 4
|
||||
|
||||
// Check CRC-32
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[:n])
|
||||
if crc.Sum32() != uint32LE(data[n:]) {
|
||||
return errors.New("xz: checksum error for block header")
|
||||
}
|
||||
|
||||
// Block header flags
|
||||
flags := data[1]
|
||||
if flags&reservedBlockFlags != 0 {
|
||||
return errors.New("xz: reserved block header flags set")
|
||||
}
|
||||
|
||||
r := bytes.NewReader(data[2:n])
|
||||
|
||||
// Compressed size
|
||||
var err error
|
||||
h.compressedSize, err = readSizeInBlockHeader(
|
||||
r, flags&compressedSizePresent != 0)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Uncompressed size
|
||||
h.uncompressedSize, err = readSizeInBlockHeader(
|
||||
r, flags&uncompressedSizePresent != 0)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
h.filters, err = readFilters(r, int(flags&filterCountMask)+1)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Check padding
|
||||
// Since headerLen is a multiple of 4 we don't need to check
|
||||
// alignment.
|
||||
k := r.Len()
|
||||
// The standard spec says that the padding should have not more
|
||||
// than 3 bytes. However we found paddings of 4 or 5 in the
|
||||
// wild. See https://github.com/ulikunitz/xz/pull/11 and
|
||||
// https://github.com/ulikunitz/xz/issues/15
|
||||
//
|
||||
// The only reasonable approach seems to be to ignore the
|
||||
// padding size. We still check that all padding bytes are zero.
|
||||
if !allZeros(data[n-k : n]) {
|
||||
return errPadding
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// MarshalBinary marshals the binary header.
|
||||
func (h *blockHeader) MarshalBinary() (data []byte, err error) {
|
||||
if !(minFilters <= len(h.filters) && len(h.filters) <= maxFilters) {
|
||||
return nil, errors.New("xz: filter count wrong")
|
||||
}
|
||||
for i, f := range h.filters {
|
||||
if i < len(h.filters)-1 {
|
||||
if f.id() == lzmaFilterID {
|
||||
return nil, errors.New(
|
||||
"xz: LZMA2 filter is not the last")
|
||||
}
|
||||
} else {
|
||||
// last filter
|
||||
if f.id() != lzmaFilterID {
|
||||
return nil, errors.New("xz: " +
|
||||
"last filter must be the LZMA2 filter")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
var buf bytes.Buffer
|
||||
// header size must set at the end
|
||||
buf.WriteByte(0)
|
||||
|
||||
// flags
|
||||
flags := byte(len(h.filters) - 1)
|
||||
if h.compressedSize >= 0 {
|
||||
flags |= compressedSizePresent
|
||||
}
|
||||
if h.uncompressedSize >= 0 {
|
||||
flags |= uncompressedSizePresent
|
||||
}
|
||||
buf.WriteByte(flags)
|
||||
|
||||
p := make([]byte, 10)
|
||||
if h.compressedSize >= 0 {
|
||||
k := putUvarint(p, uint64(h.compressedSize))
|
||||
buf.Write(p[:k])
|
||||
}
|
||||
if h.uncompressedSize >= 0 {
|
||||
k := putUvarint(p, uint64(h.uncompressedSize))
|
||||
buf.Write(p[:k])
|
||||
}
|
||||
|
||||
for _, f := range h.filters {
|
||||
fp, err := f.MarshalBinary()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
buf.Write(fp)
|
||||
}
|
||||
|
||||
// padding
|
||||
for i := padLen(int64(buf.Len())); i > 0; i-- {
|
||||
buf.WriteByte(0)
|
||||
}
|
||||
|
||||
// crc place holder
|
||||
buf.Write(p[:4])
|
||||
|
||||
data = buf.Bytes()
|
||||
if len(data)%4 != 0 {
|
||||
panic("data length not aligned")
|
||||
}
|
||||
s := len(data)/4 - 1
|
||||
if !(1 < s && s <= 255) {
|
||||
panic("wrong block header size")
|
||||
}
|
||||
data[0] = byte(s)
|
||||
|
||||
crc := crc32.NewIEEE()
|
||||
crc.Write(data[:len(data)-4])
|
||||
putUint32LE(data[len(data)-4:], crc.Sum32())
|
||||
|
||||
return data, nil
|
||||
}
|
||||
|
||||
// Constants used for marshalling and unmarshalling filters in the xz
|
||||
// block header.
|
||||
const (
|
||||
minFilters = 1
|
||||
maxFilters = 4
|
||||
minReservedID = 1 << 62
|
||||
)
|
||||
|
||||
// filter represents a filter in the block header.
|
||||
type filter interface {
|
||||
id() uint64
|
||||
UnmarshalBinary(data []byte) error
|
||||
MarshalBinary() (data []byte, err error)
|
||||
reader(r io.Reader, c *ReaderConfig) (fr io.Reader, err error)
|
||||
writeCloser(w io.WriteCloser, c *WriterConfig) (fw io.WriteCloser, err error)
|
||||
// filter must be last filter
|
||||
last() bool
|
||||
}
|
||||
|
||||
// readFilter reads a block filter from the block header. At this point
|
||||
// in time only the LZMA2 filter is supported.
|
||||
func readFilter(r io.Reader) (f filter, err error) {
|
||||
br := lzma.ByteReader(r)
|
||||
|
||||
// index
|
||||
id, _, err := readUvarint(br)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var data []byte
|
||||
switch id {
|
||||
case lzmaFilterID:
|
||||
data = make([]byte, lzmaFilterLen)
|
||||
data[0] = lzmaFilterID
|
||||
if _, err = io.ReadFull(r, data[1:]); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
f = new(lzmaFilter)
|
||||
default:
|
||||
if id >= minReservedID {
|
||||
return nil, errors.New(
|
||||
"xz: reserved filter id in block stream header")
|
||||
}
|
||||
return nil, errors.New("xz: invalid filter id")
|
||||
}
|
||||
if err = f.UnmarshalBinary(data); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return f, err
|
||||
}
|
||||
|
||||
// readFilters reads count filters. At this point in time only the count
|
||||
// 1 is supported.
|
||||
func readFilters(r io.Reader, count int) (filters []filter, err error) {
|
||||
if count != 1 {
|
||||
return nil, errors.New("xz: unsupported filter count")
|
||||
}
|
||||
f, err := readFilter(r)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return []filter{f}, err
|
||||
}
|
||||
|
||||
/*** Index ***/
|
||||
|
||||
// record describes a block in the xz file index.
|
||||
type record struct {
|
||||
unpaddedSize int64
|
||||
uncompressedSize int64
|
||||
}
|
||||
|
||||
// readRecord reads an index record.
|
||||
func readRecord(r io.ByteReader) (rec record, n int, err error) {
|
||||
u, k, err := readUvarint(r)
|
||||
n += k
|
||||
if err != nil {
|
||||
return rec, n, err
|
||||
}
|
||||
rec.unpaddedSize = int64(u)
|
||||
if rec.unpaddedSize < 0 {
|
||||
return rec, n, errors.New("xz: unpadded size negative")
|
||||
}
|
||||
|
||||
u, k, err = readUvarint(r)
|
||||
n += k
|
||||
if err != nil {
|
||||
return rec, n, err
|
||||
}
|
||||
rec.uncompressedSize = int64(u)
|
||||
if rec.uncompressedSize < 0 {
|
||||
return rec, n, errors.New("xz: uncompressed size negative")
|
||||
}
|
||||
|
||||
return rec, n, nil
|
||||
}
|
||||
|
||||
// MarshalBinary converts an index record in its binary encoding.
|
||||
func (rec *record) MarshalBinary() (data []byte, err error) {
|
||||
// maximum length of a uvarint is 10
|
||||
p := make([]byte, 20)
|
||||
n := putUvarint(p, uint64(rec.unpaddedSize))
|
||||
n += putUvarint(p[n:], uint64(rec.uncompressedSize))
|
||||
return p[:n], nil
|
||||
}
|
||||
|
||||
// writeIndex writes the index, a sequence of records.
|
||||
func writeIndex(w io.Writer, index []record) (n int64, err error) {
|
||||
crc := crc32.NewIEEE()
|
||||
mw := io.MultiWriter(w, crc)
|
||||
|
||||
// index indicator
|
||||
k, err := mw.Write([]byte{0})
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
|
||||
// number of records
|
||||
p := make([]byte, 10)
|
||||
k = putUvarint(p, uint64(len(index)))
|
||||
k, err = mw.Write(p[:k])
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
|
||||
// list of records
|
||||
for _, rec := range index {
|
||||
p, err := rec.MarshalBinary()
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
k, err = mw.Write(p)
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
|
||||
// index padding
|
||||
k, err = mw.Write(make([]byte, padLen(int64(n))))
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
|
||||
// crc32 checksum
|
||||
putUint32LE(p, crc.Sum32())
|
||||
k, err = w.Write(p[:4])
|
||||
n += int64(k)
|
||||
|
||||
return n, err
|
||||
}
|
||||
|
||||
// readIndexBody reads the index from the reader. It assumes that the
|
||||
// index indicator has already been read.
|
||||
func readIndexBody(r io.Reader, expectedRecordLen int) (records []record, n int64, err error) {
|
||||
crc := crc32.NewIEEE()
|
||||
// index indicator
|
||||
crc.Write([]byte{0})
|
||||
|
||||
br := lzma.ByteReader(io.TeeReader(r, crc))
|
||||
|
||||
// number of records
|
||||
u, k, err := readUvarint(br)
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
recLen := int(u)
|
||||
if recLen < 0 || uint64(recLen) != u {
|
||||
return nil, n, errors.New("xz: record number overflow")
|
||||
}
|
||||
if recLen != expectedRecordLen {
|
||||
return nil, n, fmt.Errorf(
|
||||
"xz: index length is %d; want %d",
|
||||
recLen, expectedRecordLen)
|
||||
}
|
||||
|
||||
// list of records
|
||||
records = make([]record, recLen)
|
||||
for i := range records {
|
||||
records[i], k, err = readRecord(br)
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
}
|
||||
|
||||
p := make([]byte, padLen(int64(n+1)), 4)
|
||||
k, err = io.ReadFull(br.(io.Reader), p)
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return nil, n, err
|
||||
}
|
||||
if !allZeros(p) {
|
||||
return nil, n, errors.New("xz: non-zero byte in index padding")
|
||||
}
|
||||
|
||||
// crc32
|
||||
s := crc.Sum32()
|
||||
p = p[:4]
|
||||
k, err = io.ReadFull(br.(io.Reader), p)
|
||||
n += int64(k)
|
||||
if err != nil {
|
||||
return records, n, err
|
||||
}
|
||||
if uint32LE(p) != s {
|
||||
return nil, n, errors.New("xz: wrong checksum for index")
|
||||
}
|
||||
|
||||
return records, n, nil
|
||||
}
|
||||
BIN
Binary file not shown.
BIN
Binary file not shown.
-181
@@ -1,181 +0,0 @@
|
||||
// Copyright 2014-2022 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 hash
|
||||
|
||||
// CyclicPoly provides a cyclic polynomial rolling hash.
|
||||
type CyclicPoly struct {
|
||||
h uint64
|
||||
p []uint64
|
||||
i int
|
||||
}
|
||||
|
||||
// ror rotates the unsigned 64-bit integer to right. The argument s must be
|
||||
// less than 64.
|
||||
func ror(x uint64, s uint) uint64 {
|
||||
return (x >> s) | (x << (64 - s))
|
||||
}
|
||||
|
||||
// NewCyclicPoly creates a new instance of the CyclicPoly structure. The
|
||||
// argument n gives the number of bytes for which a hash will be executed.
|
||||
// This number must be positive; the method panics if this isn't the case.
|
||||
func NewCyclicPoly(n int) *CyclicPoly {
|
||||
if n < 1 {
|
||||
panic("argument n must be positive")
|
||||
}
|
||||
return &CyclicPoly{p: make([]uint64, 0, n)}
|
||||
}
|
||||
|
||||
// Len returns the length of the byte sequence for which a hash is generated.
|
||||
func (r *CyclicPoly) Len() int {
|
||||
return cap(r.p)
|
||||
}
|
||||
|
||||
// RollByte hashes the next byte and returns a hash value. The complete becomes
|
||||
// available after at least Len() bytes have been hashed.
|
||||
func (r *CyclicPoly) RollByte(x byte) uint64 {
|
||||
y := hash[x]
|
||||
if len(r.p) < cap(r.p) {
|
||||
r.h = ror(r.h, 1) ^ y
|
||||
r.p = append(r.p, y)
|
||||
} else {
|
||||
r.h ^= ror(r.p[r.i], uint(cap(r.p)-1))
|
||||
r.h = ror(r.h, 1) ^ y
|
||||
r.p[r.i] = y
|
||||
r.i = (r.i + 1) % cap(r.p)
|
||||
}
|
||||
return r.h
|
||||
}
|
||||
|
||||
// Stores the hash for the individual bytes.
|
||||
var hash = [256]uint64{
|
||||
0x2e4fc3f904065142, 0xc790984cfbc99527,
|
||||
0x879f95eb8c62f187, 0x3b61be86b5021ef2,
|
||||
0x65a896a04196f0a5, 0xc5b307b80470b59e,
|
||||
0xd3bff376a70df14b, 0xc332f04f0b3f1701,
|
||||
0x753b5f0e9abf3e0d, 0xb41538fdfe66ef53,
|
||||
0x1906a10c2c1c0208, 0xfb0c712a03421c0d,
|
||||
0x38be311a65c9552b, 0xfee7ee4ca6445c7e,
|
||||
0x71aadeded184f21e, 0xd73426fccda23b2d,
|
||||
0x29773fb5fb9600b5, 0xce410261cd32981a,
|
||||
0xfe2848b3c62dbc2d, 0x459eaaff6e43e11c,
|
||||
0xc13e35fc9c73a887, 0xf30ed5c201e76dbc,
|
||||
0xa5f10b3910482cea, 0x2945d59be02dfaad,
|
||||
0x06ee334ff70571b5, 0xbabf9d8070f44380,
|
||||
0xee3e2e9912ffd27c, 0x2a7118d1ea6b8ea7,
|
||||
0x26183cb9f7b1664c, 0xea71dac7da068f21,
|
||||
0xea92eca5bd1d0bb7, 0x415595862defcd75,
|
||||
0x248a386023c60648, 0x9cf021ab284b3c8a,
|
||||
0xfc9372df02870f6c, 0x2b92d693eeb3b3fc,
|
||||
0x73e799d139dc6975, 0x7b15ae312486363c,
|
||||
0xb70e5454a2239c80, 0x208e3fb31d3b2263,
|
||||
0x01f563cabb930f44, 0x2ac4533d2a3240d8,
|
||||
0x84231ed1064f6f7c, 0xa9f020977c2a6d19,
|
||||
0x213c227271c20122, 0x09fe8a9a0a03d07a,
|
||||
0x4236dc75bcaf910c, 0x460a8b2bead8f17e,
|
||||
0xd9b27be1aa07055f, 0xd202d5dc4b11c33e,
|
||||
0x70adb010543bea12, 0xcdae938f7ea6f579,
|
||||
0x3f3d870208672f4d, 0x8e6ccbce9d349536,
|
||||
0xe4c0871a389095ae, 0xf5f2a49152bca080,
|
||||
0x9a43f9b97269934e, 0xc17b3753cb6f475c,
|
||||
0xd56d941e8e206bd4, 0xac0a4f3e525eda00,
|
||||
0xa06d5a011912a550, 0x5537ed19537ad1df,
|
||||
0xa32fe713d611449d, 0x2a1d05b47c3b579f,
|
||||
0x991d02dbd30a2a52, 0x39e91e7e28f93eb0,
|
||||
0x40d06adb3e92c9ac, 0x9b9d3afde1c77c97,
|
||||
0x9a3f3f41c02c616f, 0x22ecd4ba00f60c44,
|
||||
0x0b63d5d801708420, 0x8f227ca8f37ffaec,
|
||||
0x0256278670887c24, 0x107e14877dbf540b,
|
||||
0x32c19f2786ac1c05, 0x1df5b12bb4bc9c61,
|
||||
0xc0cac129d0d4c4e2, 0x9fdb52ee9800b001,
|
||||
0x31f601d5d31c48c4, 0x72ff3c0928bcaec7,
|
||||
0xd99264421147eb03, 0x535a2d6d38aefcfe,
|
||||
0x6ba8b4454a916237, 0xfa39366eaae4719c,
|
||||
0x10f00fd7bbb24b6f, 0x5bd23185c76c84d4,
|
||||
0xb22c3d7e1b00d33f, 0x3efc20aa6bc830a8,
|
||||
0xd61c2503fe639144, 0x30ce625441eb92d3,
|
||||
0xe5d34cf359e93100, 0xa8e5aa13f2b9f7a5,
|
||||
0x5c2b8d851ca254a6, 0x68fb6c5e8b0d5fdf,
|
||||
0xc7ea4872c96b83ae, 0x6dd5d376f4392382,
|
||||
0x1be88681aaa9792f, 0xfef465ee1b6c10d9,
|
||||
0x1f98b65ed43fcb2e, 0x4d1ca11eb6e9a9c9,
|
||||
0x7808e902b3857d0b, 0x171c9c4ea4607972,
|
||||
0x58d66274850146df, 0x42b311c10d3981d1,
|
||||
0x647fa8c621c41a4c, 0xf472771c66ddfedc,
|
||||
0x338d27e3f847b46b, 0x6402ce3da97545ce,
|
||||
0x5162db616fc38638, 0x9c83be97bc22a50e,
|
||||
0x2d3d7478a78d5e72, 0xe621a9b938fd5397,
|
||||
0x9454614eb0f81c45, 0x395fb6e742ed39b6,
|
||||
0x77dd9179d06037bf, 0xc478d0fee4d2656d,
|
||||
0x35d9d6cb772007af, 0x83a56e92c883f0f6,
|
||||
0x27937453250c00a1, 0x27bd6ebc3a46a97d,
|
||||
0x9f543bf784342d51, 0xd158f38c48b0ed52,
|
||||
0x8dd8537c045f66b4, 0x846a57230226f6d5,
|
||||
0x6b13939e0c4e7cdf, 0xfca25425d8176758,
|
||||
0x92e5fc6cd52788e6, 0x9992e13d7a739170,
|
||||
0x518246f7a199e8ea, 0xf104c2a71b9979c7,
|
||||
0x86b3ffaabea4768f, 0x6388061cf3e351ad,
|
||||
0x09d9b5295de5bbb5, 0x38bf1638c2599e92,
|
||||
0x1d759846499e148d, 0x4c0ff015e5f96ef4,
|
||||
0xa41a94cfa270f565, 0x42d76f9cb2326c0b,
|
||||
0x0cf385dd3c9c23ba, 0x0508a6c7508d6e7a,
|
||||
0x337523aabbe6cf8d, 0x646bb14001d42b12,
|
||||
0xc178729d138adc74, 0xf900ef4491f24086,
|
||||
0xee1a90d334bb5ac4, 0x9755c92247301a50,
|
||||
0xb999bf7c4ff1b610, 0x6aeeb2f3b21e8fc9,
|
||||
0x0fa8084cf91ac6ff, 0x10d226cf136e6189,
|
||||
0xd302057a07d4fb21, 0x5f03800e20a0fcc3,
|
||||
0x80118d4ae46bd210, 0x58ab61a522843733,
|
||||
0x51edd575c5432a4b, 0x94ee6ff67f9197f7,
|
||||
0x765669e0e5e8157b, 0xa5347830737132f0,
|
||||
0x3ba485a69f01510c, 0x0b247d7b957a01c3,
|
||||
0x1b3d63449fd807dc, 0x0fdc4721c30ad743,
|
||||
0x8b535ed3829b2b14, 0xee41d0cad65d232c,
|
||||
0xe6a99ed97a6a982f, 0x65ac6194c202003d,
|
||||
0x692accf3a70573eb, 0xcc3c02c3e200d5af,
|
||||
0x0d419e8b325914a3, 0x320f160f42c25e40,
|
||||
0x00710d647a51fe7a, 0x3c947692330aed60,
|
||||
0x9288aa280d355a7a, 0xa1806a9b791d1696,
|
||||
0x5d60e38496763da1, 0x6c69e22e613fd0f4,
|
||||
0x977fc2a5aadffb17, 0xfb7bd063fc5a94ba,
|
||||
0x460c17992cbaece1, 0xf7822c5444d3297f,
|
||||
0x344a9790c69b74aa, 0xb80a42e6cae09dce,
|
||||
0x1b1361eaf2b1e757, 0xd84c1e758e236f01,
|
||||
0x88e0b7be347627cc, 0x45246009b7a99490,
|
||||
0x8011c6dd3fe50472, 0xc341d682bffb99d7,
|
||||
0x2511be93808e2d15, 0xd5bc13d7fd739840,
|
||||
0x2a3cd030679ae1ec, 0x8ad9898a4b9ee157,
|
||||
0x3245fef0a8eaf521, 0x3d6d8dbbb427d2b0,
|
||||
0x1ed146d8968b3981, 0x0c6a28bf7d45f3fc,
|
||||
0x4a1fd3dbcee3c561, 0x4210ff6a476bf67e,
|
||||
0xa559cce0d9199aac, 0xde39d47ef3723380,
|
||||
0xe5b69d848ce42e35, 0xefa24296f8e79f52,
|
||||
0x70190b59db9a5afc, 0x26f166cdb211e7bf,
|
||||
0x4deaf2df3c6b8ef5, 0xf171dbdd670f1017,
|
||||
0xb9059b05e9420d90, 0x2f0da855c9388754,
|
||||
0x611d5e9ab77949cc, 0x2912038ac01163f4,
|
||||
0x0231df50402b2fba, 0x45660fc4f3245f58,
|
||||
0xb91cc97c7c8dac50, 0xb72d2aafe4953427,
|
||||
0xfa6463f87e813d6b, 0x4515f7ee95d5c6a2,
|
||||
0x1310e1c1a48d21c3, 0xad48a7810cdd8544,
|
||||
0x4d5bdfefd5c9e631, 0xa43ed43f1fdcb7de,
|
||||
0xe70cfc8fe1ee9626, 0xef4711b0d8dda442,
|
||||
0xb80dd9bd4dab6c93, 0xa23be08d31ba4d93,
|
||||
0x9b37db9d0335a39c, 0x494b6f870f5cfebc,
|
||||
0x6d1b3c1149dda943, 0x372c943a518c1093,
|
||||
0xad27af45e77c09c4, 0x3b6f92b646044604,
|
||||
0xac2917909f5fcf4f, 0x2069a60e977e5557,
|
||||
0x353a469e71014de5, 0x24be356281f55c15,
|
||||
0x2b6d710ba8e9adea, 0x404ad1751c749c29,
|
||||
0xed7311bf23d7f185, 0xba4f6976b4acc43e,
|
||||
0x32d7198d2bc39000, 0xee667019014d6e01,
|
||||
0x494ef3e128d14c83, 0x1f95a152baecd6be,
|
||||
0x201648dff1f483a5, 0x68c28550c8384af6,
|
||||
0x5fc834a6824a7f48, 0x7cd06cb7365eaf28,
|
||||
0xd82bbd95e9b30909, 0x234f0d1694c53f6d,
|
||||
0xd2fb7f4a96d83f4a, 0xff0d5da83acac05e,
|
||||
0xf8f6b97f5585080a, 0x74236084be57b95b,
|
||||
0xa25e40c03bbc36ad, 0x6b6e5c14ce88465b,
|
||||
0x4378ffe93e1528c5, 0x94ca92a17118e2d2,
|
||||
}
|
||||
-14
@@ -1,14 +0,0 @@
|
||||
// Copyright 2014-2022 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 hash provides rolling hashes.
|
||||
|
||||
Rolling hashes have to be used for maintaining the positions of n-byte
|
||||
sequences in the dictionary buffer.
|
||||
|
||||
The package provides currently the Rabin-Karp rolling hash and a Cyclic
|
||||
Polynomial hash. Both support the Hashes method to be used with an interface.
|
||||
*/
|
||||
package hash
|
||||
-66
@@ -1,66 +0,0 @@
|
||||
// Copyright 2014-2022 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 hash
|
||||
|
||||
// A is the default constant for Robin-Karp rolling hash. This is a random
|
||||
// prime.
|
||||
const A = 0x97b548add41d5da1
|
||||
|
||||
// RabinKarp supports the computation of a rolling hash.
|
||||
type RabinKarp struct {
|
||||
A uint64
|
||||
// a^n
|
||||
aOldest uint64
|
||||
h uint64
|
||||
p []byte
|
||||
i int
|
||||
}
|
||||
|
||||
// NewRabinKarp creates a new RabinKarp value. The argument n defines the
|
||||
// length of the byte sequence to be hashed. The default constant will will be
|
||||
// used.
|
||||
func NewRabinKarp(n int) *RabinKarp {
|
||||
return NewRabinKarpConst(n, A)
|
||||
}
|
||||
|
||||
// NewRabinKarpConst creates a new RabinKarp value. The argument n defines the
|
||||
// length of the byte sequence to be hashed. The argument a provides the
|
||||
// constant used to compute the hash.
|
||||
func NewRabinKarpConst(n int, a uint64) *RabinKarp {
|
||||
if n <= 0 {
|
||||
panic("number of bytes n must be positive")
|
||||
}
|
||||
aOldest := uint64(1)
|
||||
// There are faster methods. For the small n required by the LZMA
|
||||
// compressor O(n) is sufficient.
|
||||
for i := 0; i < n; i++ {
|
||||
aOldest *= a
|
||||
}
|
||||
return &RabinKarp{
|
||||
A: a, aOldest: aOldest,
|
||||
p: make([]byte, 0, n),
|
||||
}
|
||||
}
|
||||
|
||||
// Len returns the length of the byte sequence.
|
||||
func (r *RabinKarp) Len() int {
|
||||
return cap(r.p)
|
||||
}
|
||||
|
||||
// RollByte computes the hash after x has been added.
|
||||
func (r *RabinKarp) RollByte(x byte) uint64 {
|
||||
if len(r.p) < cap(r.p) {
|
||||
r.h += uint64(x)
|
||||
r.h *= r.A
|
||||
r.p = append(r.p, x)
|
||||
} else {
|
||||
r.h -= uint64(r.p[r.i]) * r.aOldest
|
||||
r.h += uint64(x)
|
||||
r.h *= r.A
|
||||
r.p[r.i] = x
|
||||
r.i = (r.i + 1) % cap(r.p)
|
||||
}
|
||||
return r.h
|
||||
}
|
||||
-29
@@ -1,29 +0,0 @@
|
||||
// Copyright 2014-2022 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 hash
|
||||
|
||||
// Roller provides an interface for rolling hashes. The hash value will become
|
||||
// valid after hash has been called Len times.
|
||||
type Roller interface {
|
||||
Len() int
|
||||
RollByte(x byte) uint64
|
||||
}
|
||||
|
||||
// Hashes computes all hash values for the array p. Note that the state of the
|
||||
// roller is changed.
|
||||
func Hashes(r Roller, p []byte) []uint64 {
|
||||
n := r.Len()
|
||||
if len(p) < n {
|
||||
return nil
|
||||
}
|
||||
h := make([]uint64, len(p)-n+1)
|
||||
for i := 0; i < n-1; i++ {
|
||||
r.RollByte(p[i])
|
||||
}
|
||||
for i := range h {
|
||||
h[i] = r.RollByte(p[i+n-1])
|
||||
}
|
||||
return h
|
||||
}
|
||||
-456
@@ -1,456 +0,0 @@
|
||||
// Copyright 2014-2022 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 xlog provides a simple logging package that allows to disable
|
||||
// certain message categories. It defines a type, Logger, with multiple
|
||||
// methods for formatting output. The package has also a predefined
|
||||
// 'standard' Logger accessible through helper function Print[f|ln],
|
||||
// Fatal[f|ln], Panic[f|ln], Warn[f|ln], Print[f|ln] and Debug[f|ln]
|
||||
// that are easier to use then creating a Logger manually. That logger
|
||||
// writes to standard error and prints the date and time of each logged
|
||||
// message, which can be configured using the function SetFlags.
|
||||
//
|
||||
// The Fatal functions call os.Exit(1) after the message is output
|
||||
// unless not suppressed by the flags. The Panic functions call panic
|
||||
// after the writing the log message unless suppressed.
|
||||
package xlog
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"io"
|
||||
"os"
|
||||
"runtime"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// The flags define what information is prefixed to each log entry
|
||||
// generated by the Logger. The Lno* versions allow the suppression of
|
||||
// specific output. The bits are or'ed together to control what will be
|
||||
// printed. There is no control over the order of the items printed and
|
||||
// the format. The full format is:
|
||||
//
|
||||
// 2009-01-23 01:23:23.123123 /a/b/c/d.go:23: message
|
||||
const (
|
||||
Ldate = 1 << iota // the date: 2009-01-23
|
||||
Ltime // the time: 01:23:23
|
||||
Lmicroseconds // microsecond resolution: 01:23:23.123123
|
||||
Llongfile // full file name and line number: /a/b/c/d.go:23
|
||||
Lshortfile // final file name element and line number: d.go:23
|
||||
Lnopanic // suppresses output from Panic[f|ln] but not the panic call
|
||||
Lnofatal // suppresses output from Fatal[f|ln] but not the exit
|
||||
Lnowarn // suppresses output from Warn[f|ln]
|
||||
Lnoprint // suppresses output from Print[f|ln]
|
||||
Lnodebug // suppresses output from Debug[f|ln]
|
||||
// initial values for the standard logger
|
||||
Lstdflags = Ldate | Ltime | Lnodebug
|
||||
)
|
||||
|
||||
// A Logger represents an active logging object that generates lines of
|
||||
// output to an io.Writer. Each logging operation if not suppressed
|
||||
// makes a single call to the Writer's Write method. A Logger can be
|
||||
// used simultaneously from multiple goroutines; it guarantees to
|
||||
// serialize access to the Writer.
|
||||
type Logger struct {
|
||||
mu sync.Mutex // ensures atomic writes; and protects the following
|
||||
// fields
|
||||
prefix string // prefix to write at beginning of each line
|
||||
flag int // properties
|
||||
out io.Writer // destination for output
|
||||
buf []byte // for accumulating text to write
|
||||
}
|
||||
|
||||
// New creates a new Logger. The out argument sets the destination to
|
||||
// which the log output will be written. The prefix appears at the
|
||||
// beginning of each log line. The flag argument defines the logging
|
||||
// properties.
|
||||
func New(out io.Writer, prefix string, flag int) *Logger {
|
||||
return &Logger{out: out, prefix: prefix, flag: flag}
|
||||
}
|
||||
|
||||
// std is the standard logger used by the package scope functions.
|
||||
var std = New(os.Stderr, "", Lstdflags)
|
||||
|
||||
// itoa converts the integer to ASCII. A negative widths will avoid
|
||||
// zero-padding. The function supports only non-negative integers.
|
||||
func itoa(buf *[]byte, i int, wid int) {
|
||||
var u = uint(i)
|
||||
if u == 0 && wid <= 1 {
|
||||
*buf = append(*buf, '0')
|
||||
return
|
||||
}
|
||||
var b [32]byte
|
||||
bp := len(b)
|
||||
for ; u > 0 || wid > 0; u /= 10 {
|
||||
bp--
|
||||
wid--
|
||||
b[bp] = byte(u%10) + '0'
|
||||
}
|
||||
*buf = append(*buf, b[bp:]...)
|
||||
}
|
||||
|
||||
// formatHeader puts the header into the buf field of the buffer.
|
||||
func (l *Logger) formatHeader(t time.Time, file string, line int) {
|
||||
l.buf = append(l.buf, l.prefix...)
|
||||
if l.flag&(Ldate|Ltime|Lmicroseconds) != 0 {
|
||||
if l.flag&Ldate != 0 {
|
||||
year, month, day := t.Date()
|
||||
itoa(&l.buf, year, 4)
|
||||
l.buf = append(l.buf, '-')
|
||||
itoa(&l.buf, int(month), 2)
|
||||
l.buf = append(l.buf, '-')
|
||||
itoa(&l.buf, day, 2)
|
||||
l.buf = append(l.buf, ' ')
|
||||
}
|
||||
if l.flag&(Ltime|Lmicroseconds) != 0 {
|
||||
hour, min, sec := t.Clock()
|
||||
itoa(&l.buf, hour, 2)
|
||||
l.buf = append(l.buf, ':')
|
||||
itoa(&l.buf, min, 2)
|
||||
l.buf = append(l.buf, ':')
|
||||
itoa(&l.buf, sec, 2)
|
||||
if l.flag&Lmicroseconds != 0 {
|
||||
l.buf = append(l.buf, '.')
|
||||
itoa(&l.buf, t.Nanosecond()/1e3, 6)
|
||||
}
|
||||
l.buf = append(l.buf, ' ')
|
||||
}
|
||||
}
|
||||
if l.flag&(Lshortfile|Llongfile) != 0 {
|
||||
if l.flag&Lshortfile != 0 {
|
||||
short := file
|
||||
for i := len(file) - 1; i > 0; i-- {
|
||||
if file[i] == '/' {
|
||||
short = file[i+1:]
|
||||
break
|
||||
}
|
||||
}
|
||||
file = short
|
||||
}
|
||||
l.buf = append(l.buf, file...)
|
||||
l.buf = append(l.buf, ':')
|
||||
itoa(&l.buf, line, -1)
|
||||
l.buf = append(l.buf, ": "...)
|
||||
}
|
||||
}
|
||||
|
||||
func (l *Logger) output(calldepth int, now time.Time, s string) error {
|
||||
var file string
|
||||
var line int
|
||||
if l.flag&(Lshortfile|Llongfile) != 0 {
|
||||
l.mu.Unlock()
|
||||
var ok bool
|
||||
_, file, line, ok = runtime.Caller(calldepth)
|
||||
if !ok {
|
||||
file = "???"
|
||||
line = 0
|
||||
}
|
||||
l.mu.Lock()
|
||||
}
|
||||
l.buf = l.buf[:0]
|
||||
l.formatHeader(now, file, line)
|
||||
l.buf = append(l.buf, s...)
|
||||
if len(s) == 0 || s[len(s)-1] != '\n' {
|
||||
l.buf = append(l.buf, '\n')
|
||||
}
|
||||
_, err := l.out.Write(l.buf)
|
||||
return err
|
||||
}
|
||||
|
||||
// Output writes the string s with the header controlled by the flags to
|
||||
// the l.out writer. A newline will be appended if s doesn't end in a
|
||||
// newline. Calldepth is used to recover the PC, although all current
|
||||
// calls of Output use the call depth 2. Access to the function is serialized.
|
||||
func (l *Logger) Output(calldepth, noflag int, v ...interface{}) error {
|
||||
now := time.Now()
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
if l.flag&noflag != 0 {
|
||||
return nil
|
||||
}
|
||||
s := fmt.Sprint(v...)
|
||||
return l.output(calldepth+1, now, s)
|
||||
}
|
||||
|
||||
// Outputf works like output but formats the output like Printf.
|
||||
func (l *Logger) Outputf(calldepth int, noflag int, format string, v ...interface{}) error {
|
||||
now := time.Now()
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
if l.flag&noflag != 0 {
|
||||
return nil
|
||||
}
|
||||
s := fmt.Sprintf(format, v...)
|
||||
return l.output(calldepth+1, now, s)
|
||||
}
|
||||
|
||||
// Outputln works like output but formats the output like Println.
|
||||
func (l *Logger) Outputln(calldepth int, noflag int, v ...interface{}) error {
|
||||
now := time.Now()
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
if l.flag&noflag != 0 {
|
||||
return nil
|
||||
}
|
||||
s := fmt.Sprintln(v...)
|
||||
return l.output(calldepth+1, now, s)
|
||||
}
|
||||
|
||||
// Panic prints the message like Print and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func (l *Logger) Panic(v ...interface{}) {
|
||||
l.Output(2, Lnopanic, v...)
|
||||
s := fmt.Sprint(v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Panic prints the message like Print and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func Panic(v ...interface{}) {
|
||||
std.Output(2, Lnopanic, v...)
|
||||
s := fmt.Sprint(v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Panicf prints the message like Printf and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func (l *Logger) Panicf(format string, v ...interface{}) {
|
||||
l.Outputf(2, Lnopanic, format, v...)
|
||||
s := fmt.Sprintf(format, v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Panicf prints the message like Printf and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func Panicf(format string, v ...interface{}) {
|
||||
std.Outputf(2, Lnopanic, format, v...)
|
||||
s := fmt.Sprintf(format, v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Panicln prints the message like Println and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func (l *Logger) Panicln(v ...interface{}) {
|
||||
l.Outputln(2, Lnopanic, v...)
|
||||
s := fmt.Sprintln(v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Panicln prints the message like Println and calls panic. The printing
|
||||
// might be suppressed by the flag Lnopanic.
|
||||
func Panicln(v ...interface{}) {
|
||||
std.Outputln(2, Lnopanic, v...)
|
||||
s := fmt.Sprintln(v...)
|
||||
panic(s)
|
||||
}
|
||||
|
||||
// Fatal prints the message like Print and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func (l *Logger) Fatal(v ...interface{}) {
|
||||
l.Output(2, Lnofatal, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Fatal prints the message like Print and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func Fatal(v ...interface{}) {
|
||||
std.Output(2, Lnofatal, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Fatalf prints the message like Printf and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func (l *Logger) Fatalf(format string, v ...interface{}) {
|
||||
l.Outputf(2, Lnofatal, format, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Fatalf prints the message like Printf and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func Fatalf(format string, v ...interface{}) {
|
||||
std.Outputf(2, Lnofatal, format, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Fatalln prints the message like Println and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func (l *Logger) Fatalln(format string, v ...interface{}) {
|
||||
l.Outputln(2, Lnofatal, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Fatalln prints the message like Println and calls os.Exit(1). The
|
||||
// printing might be suppressed by the flag Lnofatal.
|
||||
func Fatalln(format string, v ...interface{}) {
|
||||
std.Outputln(2, Lnofatal, v...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Warn prints the message like Print. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func (l *Logger) Warn(v ...interface{}) {
|
||||
l.Output(2, Lnowarn, v...)
|
||||
}
|
||||
|
||||
// Warn prints the message like Print. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func Warn(v ...interface{}) {
|
||||
std.Output(2, Lnowarn, v...)
|
||||
}
|
||||
|
||||
// Warnf prints the message like Printf. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func (l *Logger) Warnf(format string, v ...interface{}) {
|
||||
l.Outputf(2, Lnowarn, format, v...)
|
||||
}
|
||||
|
||||
// Warnf prints the message like Printf. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func Warnf(format string, v ...interface{}) {
|
||||
std.Outputf(2, Lnowarn, format, v...)
|
||||
}
|
||||
|
||||
// Warnln prints the message like Println. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func (l *Logger) Warnln(v ...interface{}) {
|
||||
l.Outputln(2, Lnowarn, v...)
|
||||
}
|
||||
|
||||
// Warnln prints the message like Println. The printing might be suppressed
|
||||
// by the flag Lnowarn.
|
||||
func Warnln(v ...interface{}) {
|
||||
std.Outputln(2, Lnowarn, v...)
|
||||
}
|
||||
|
||||
// Print prints the message like fmt.Print. The printing might be suppressed
|
||||
// by the flag Lnoprint.
|
||||
func (l *Logger) Print(v ...interface{}) {
|
||||
l.Output(2, Lnoprint, v...)
|
||||
}
|
||||
|
||||
// Print prints the message like fmt.Print. The printing might be suppressed
|
||||
// by the flag Lnoprint.
|
||||
func Print(v ...interface{}) {
|
||||
std.Output(2, Lnoprint, v...)
|
||||
}
|
||||
|
||||
// Printf prints the message like fmt.Printf. The printing might be suppressed
|
||||
// by the flag Lnoprint.
|
||||
func (l *Logger) Printf(format string, v ...interface{}) {
|
||||
l.Outputf(2, Lnoprint, format, v...)
|
||||
}
|
||||
|
||||
// Printf prints the message like fmt.Printf. The printing might be suppressed
|
||||
// by the flag Lnoprint.
|
||||
func Printf(format string, v ...interface{}) {
|
||||
std.Outputf(2, Lnoprint, format, v...)
|
||||
}
|
||||
|
||||
// Println prints the message like fmt.Println. The printing might be
|
||||
// suppressed by the flag Lnoprint.
|
||||
func (l *Logger) Println(v ...interface{}) {
|
||||
l.Outputln(2, Lnoprint, v...)
|
||||
}
|
||||
|
||||
// Println prints the message like fmt.Println. The printing might be
|
||||
// suppressed by the flag Lnoprint.
|
||||
func Println(v ...interface{}) {
|
||||
std.Outputln(2, Lnoprint, v...)
|
||||
}
|
||||
|
||||
// Debug prints the message like Print. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func (l *Logger) Debug(v ...interface{}) {
|
||||
l.Output(2, Lnodebug, v...)
|
||||
}
|
||||
|
||||
// Debug prints the message like Print. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func Debug(v ...interface{}) {
|
||||
std.Output(2, Lnodebug, v...)
|
||||
}
|
||||
|
||||
// Debugf prints the message like Printf. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func (l *Logger) Debugf(format string, v ...interface{}) {
|
||||
l.Outputf(2, Lnodebug, format, v...)
|
||||
}
|
||||
|
||||
// Debugf prints the message like Printf. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func Debugf(format string, v ...interface{}) {
|
||||
std.Outputf(2, Lnodebug, format, v...)
|
||||
}
|
||||
|
||||
// Debugln prints the message like Println. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func (l *Logger) Debugln(v ...interface{}) {
|
||||
l.Outputln(2, Lnodebug, v...)
|
||||
}
|
||||
|
||||
// Debugln prints the message like Println. The printing might be suppressed
|
||||
// by the flag Lnodebug.
|
||||
func Debugln(v ...interface{}) {
|
||||
std.Outputln(2, Lnodebug, v...)
|
||||
}
|
||||
|
||||
// Flags returns the current flags used by the logger.
|
||||
func (l *Logger) Flags() int {
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
return l.flag
|
||||
}
|
||||
|
||||
// Flags returns the current flags used by the standard logger.
|
||||
func Flags() int {
|
||||
return std.Flags()
|
||||
}
|
||||
|
||||
// SetFlags sets the flags of the logger.
|
||||
func (l *Logger) SetFlags(flag int) {
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
l.flag = flag
|
||||
}
|
||||
|
||||
// SetFlags sets the flags for the standard logger.
|
||||
func SetFlags(flag int) {
|
||||
std.SetFlags(flag)
|
||||
}
|
||||
|
||||
// Prefix returns the prefix used by the logger.
|
||||
func (l *Logger) Prefix() string {
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
return l.prefix
|
||||
}
|
||||
|
||||
// Prefix returns the prefix used by the standard logger of the package.
|
||||
func Prefix() string {
|
||||
return std.Prefix()
|
||||
}
|
||||
|
||||
// SetPrefix sets the prefix for the logger.
|
||||
func (l *Logger) SetPrefix(prefix string) {
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
l.prefix = prefix
|
||||
}
|
||||
|
||||
// SetPrefix sets the prefix of the standard logger of the package.
|
||||
func SetPrefix(prefix string) {
|
||||
std.SetPrefix(prefix)
|
||||
}
|
||||
|
||||
// SetOutput sets the output of the logger.
|
||||
func (l *Logger) SetOutput(w io.Writer) {
|
||||
l.mu.Lock()
|
||||
defer l.mu.Unlock()
|
||||
l.out = w
|
||||
}
|
||||
|
||||
// SetOutput sets the output for the standard logger of the package.
|
||||
func SetOutput(w io.Writer) {
|
||||
std.SetOutput(w)
|
||||
}
|
||||
-522
@@ -1,522 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
"unicode"
|
||||
)
|
||||
|
||||
// node represents a node in the binary tree.
|
||||
type node struct {
|
||||
// x is the search value
|
||||
x uint32
|
||||
// p parent node
|
||||
p uint32
|
||||
// l left child
|
||||
l uint32
|
||||
// r right child
|
||||
r uint32
|
||||
}
|
||||
|
||||
// wordLen is the number of bytes represented by the v field of a node.
|
||||
const wordLen = 4
|
||||
|
||||
// binTree supports the identification of the next operation based on a
|
||||
// binary tree.
|
||||
//
|
||||
// Nodes will be identified by their index into the ring buffer.
|
||||
type binTree struct {
|
||||
dict *encoderDict
|
||||
// ring buffer of nodes
|
||||
node []node
|
||||
// absolute offset of the entry for the next node. Position 4
|
||||
// byte larger.
|
||||
hoff int64
|
||||
// front position in the node ring buffer
|
||||
front uint32
|
||||
// index of the root node
|
||||
root uint32
|
||||
// current x value
|
||||
x uint32
|
||||
// preallocated array
|
||||
data []byte
|
||||
}
|
||||
|
||||
// null represents the nonexistent index. We can't use zero because it
|
||||
// would always exist or we would need to decrease the index for each
|
||||
// reference.
|
||||
const null uint32 = 1<<32 - 1
|
||||
|
||||
// newBinTree initializes the binTree structure. The capacity defines
|
||||
// the size of the buffer and defines the maximum distance for which
|
||||
// matches will be found.
|
||||
func newBinTree(capacity int) (t *binTree, err error) {
|
||||
if capacity < 1 {
|
||||
return nil, errors.New(
|
||||
"newBinTree: capacity must be larger than zero")
|
||||
}
|
||||
if int64(capacity) >= int64(null) {
|
||||
return nil, errors.New(
|
||||
"newBinTree: capacity must less 2^{32}-1")
|
||||
}
|
||||
t = &binTree{
|
||||
node: make([]node, capacity),
|
||||
hoff: -int64(wordLen),
|
||||
root: null,
|
||||
data: make([]byte, maxMatchLen),
|
||||
}
|
||||
return t, nil
|
||||
}
|
||||
|
||||
func (t *binTree) SetDict(d *encoderDict) { t.dict = d }
|
||||
|
||||
// WriteByte writes a single byte into the binary tree.
|
||||
func (t *binTree) WriteByte(c byte) error {
|
||||
t.x = (t.x << 8) | uint32(c)
|
||||
t.hoff++
|
||||
if t.hoff < 0 {
|
||||
return nil
|
||||
}
|
||||
v := t.front
|
||||
if int64(v) < t.hoff {
|
||||
// We are overwriting old nodes stored in the tree.
|
||||
t.remove(v)
|
||||
}
|
||||
t.node[v].x = t.x
|
||||
t.add(v)
|
||||
t.front++
|
||||
if int64(t.front) >= int64(len(t.node)) {
|
||||
t.front = 0
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Writes writes a sequence of bytes into the binTree structure.
|
||||
func (t *binTree) Write(p []byte) (n int, err error) {
|
||||
for _, c := range p {
|
||||
t.WriteByte(c)
|
||||
}
|
||||
return len(p), nil
|
||||
}
|
||||
|
||||
// add puts the node v into the tree. The node must not be part of the
|
||||
// tree before.
|
||||
func (t *binTree) add(v uint32) {
|
||||
vn := &t.node[v]
|
||||
// Set left and right to null indices.
|
||||
vn.l, vn.r = null, null
|
||||
// If the binary tree is empty make v the root.
|
||||
if t.root == null {
|
||||
t.root = v
|
||||
vn.p = null
|
||||
return
|
||||
}
|
||||
x := vn.x
|
||||
p := t.root
|
||||
// Search for the right leave link and add the new node.
|
||||
for {
|
||||
pn := &t.node[p]
|
||||
if x <= pn.x {
|
||||
if pn.l == null {
|
||||
pn.l = v
|
||||
vn.p = p
|
||||
return
|
||||
}
|
||||
p = pn.l
|
||||
} else {
|
||||
if pn.r == null {
|
||||
pn.r = v
|
||||
vn.p = p
|
||||
return
|
||||
}
|
||||
p = pn.r
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// parent returns the parent node index of v and the pointer to v value
|
||||
// in the parent.
|
||||
func (t *binTree) parent(v uint32) (p uint32, ptr *uint32) {
|
||||
if t.root == v {
|
||||
return null, &t.root
|
||||
}
|
||||
p = t.node[v].p
|
||||
if t.node[p].l == v {
|
||||
ptr = &t.node[p].l
|
||||
} else {
|
||||
ptr = &t.node[p].r
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// Remove node v.
|
||||
func (t *binTree) remove(v uint32) {
|
||||
vn := &t.node[v]
|
||||
p, ptr := t.parent(v)
|
||||
l, r := vn.l, vn.r
|
||||
if l == null {
|
||||
// Move the right child up.
|
||||
*ptr = r
|
||||
if r != null {
|
||||
t.node[r].p = p
|
||||
}
|
||||
return
|
||||
}
|
||||
if r == null {
|
||||
// Move the left child up.
|
||||
*ptr = l
|
||||
t.node[l].p = p
|
||||
return
|
||||
}
|
||||
|
||||
// Search the in-order predecessor u.
|
||||
un := &t.node[l]
|
||||
ur := un.r
|
||||
if ur == null {
|
||||
// In order predecessor is l. Move it up.
|
||||
un.r = r
|
||||
t.node[r].p = l
|
||||
un.p = p
|
||||
*ptr = l
|
||||
return
|
||||
}
|
||||
var u uint32
|
||||
for {
|
||||
// Look for the max value in the tree where l is root.
|
||||
u = ur
|
||||
ur = t.node[u].r
|
||||
if ur == null {
|
||||
break
|
||||
}
|
||||
}
|
||||
// replace u with ul
|
||||
un = &t.node[u]
|
||||
ul := un.l
|
||||
up := un.p
|
||||
t.node[up].r = ul
|
||||
if ul != null {
|
||||
t.node[ul].p = up
|
||||
}
|
||||
|
||||
// replace v by u
|
||||
un.l, un.r = l, r
|
||||
t.node[l].p = u
|
||||
t.node[r].p = u
|
||||
*ptr = u
|
||||
un.p = p
|
||||
}
|
||||
|
||||
// search looks for the node that have the value x or for the nodes that
|
||||
// brace it. The node highest in the tree with the value x will be
|
||||
// returned. All other nodes with the same value live in left subtree of
|
||||
// the returned node.
|
||||
func (t *binTree) search(v uint32, x uint32) (a, b uint32) {
|
||||
a, b = null, null
|
||||
if v == null {
|
||||
return
|
||||
}
|
||||
for {
|
||||
vn := &t.node[v]
|
||||
if x <= vn.x {
|
||||
if x == vn.x {
|
||||
return v, v
|
||||
}
|
||||
b = v
|
||||
if vn.l == null {
|
||||
return
|
||||
}
|
||||
v = vn.l
|
||||
} else {
|
||||
a = v
|
||||
if vn.r == null {
|
||||
return
|
||||
}
|
||||
v = vn.r
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// max returns the node with maximum value in the subtree with v as
|
||||
// root.
|
||||
func (t *binTree) max(v uint32) uint32 {
|
||||
if v == null {
|
||||
return null
|
||||
}
|
||||
for {
|
||||
r := t.node[v].r
|
||||
if r == null {
|
||||
return v
|
||||
}
|
||||
v = r
|
||||
}
|
||||
}
|
||||
|
||||
// min returns the node with the minimum value in the subtree with v as
|
||||
// root.
|
||||
func (t *binTree) min(v uint32) uint32 {
|
||||
if v == null {
|
||||
return null
|
||||
}
|
||||
for {
|
||||
l := t.node[v].l
|
||||
if l == null {
|
||||
return v
|
||||
}
|
||||
v = l
|
||||
}
|
||||
}
|
||||
|
||||
// pred returns the in-order predecessor of node v.
|
||||
func (t *binTree) pred(v uint32) uint32 {
|
||||
if v == null {
|
||||
return null
|
||||
}
|
||||
u := t.max(t.node[v].l)
|
||||
if u != null {
|
||||
return u
|
||||
}
|
||||
for {
|
||||
p := t.node[v].p
|
||||
if p == null {
|
||||
return null
|
||||
}
|
||||
if t.node[p].r == v {
|
||||
return p
|
||||
}
|
||||
v = p
|
||||
}
|
||||
}
|
||||
|
||||
// succ returns the in-order successor of node v.
|
||||
func (t *binTree) succ(v uint32) uint32 {
|
||||
if v == null {
|
||||
return null
|
||||
}
|
||||
u := t.min(t.node[v].r)
|
||||
if u != null {
|
||||
return u
|
||||
}
|
||||
for {
|
||||
p := t.node[v].p
|
||||
if p == null {
|
||||
return null
|
||||
}
|
||||
if t.node[p].l == v {
|
||||
return p
|
||||
}
|
||||
v = p
|
||||
}
|
||||
}
|
||||
|
||||
// xval converts the first four bytes of a into an 32-bit unsigned
|
||||
// integer in big-endian order.
|
||||
func xval(a []byte) uint32 {
|
||||
var x uint32
|
||||
switch len(a) {
|
||||
default:
|
||||
x |= uint32(a[3])
|
||||
fallthrough
|
||||
case 3:
|
||||
x |= uint32(a[2]) << 8
|
||||
fallthrough
|
||||
case 2:
|
||||
x |= uint32(a[1]) << 16
|
||||
fallthrough
|
||||
case 1:
|
||||
x |= uint32(a[0]) << 24
|
||||
case 0:
|
||||
}
|
||||
return x
|
||||
}
|
||||
|
||||
// dumpX converts value x into a four-letter string.
|
||||
func dumpX(x uint32) string {
|
||||
a := make([]byte, 4)
|
||||
for i := 0; i < 4; i++ {
|
||||
c := byte(x >> uint((3-i)*8))
|
||||
if unicode.IsGraphic(rune(c)) {
|
||||
a[i] = c
|
||||
} else {
|
||||
a[i] = '.'
|
||||
}
|
||||
}
|
||||
return string(a)
|
||||
}
|
||||
|
||||
/*
|
||||
// dumpNode writes a representation of the node v into the io.Writer.
|
||||
func (t *binTree) dumpNode(w io.Writer, v uint32, indent int) {
|
||||
if v == null {
|
||||
return
|
||||
}
|
||||
|
||||
vn := &t.node[v]
|
||||
|
||||
t.dumpNode(w, vn.r, indent+2)
|
||||
|
||||
for i := 0; i < indent; i++ {
|
||||
fmt.Fprint(w, " ")
|
||||
}
|
||||
if vn.p == null {
|
||||
fmt.Fprintf(w, "node %d %q parent null\n", v, dumpX(vn.x))
|
||||
} else {
|
||||
fmt.Fprintf(w, "node %d %q parent %d\n", v, dumpX(vn.x), vn.p)
|
||||
}
|
||||
|
||||
t.dumpNode(w, vn.l, indent+2)
|
||||
}
|
||||
|
||||
// dump prints a representation of the binary tree into the writer.
|
||||
func (t *binTree) dump(w io.Writer) error {
|
||||
bw := bufio.NewWriter(w)
|
||||
t.dumpNode(bw, t.root, 0)
|
||||
return bw.Flush()
|
||||
}
|
||||
*/
|
||||
|
||||
func (t *binTree) distance(v uint32) int {
|
||||
dist := int(t.front) - int(v)
|
||||
if dist <= 0 {
|
||||
dist += len(t.node)
|
||||
}
|
||||
return dist
|
||||
}
|
||||
|
||||
type matchParams struct {
|
||||
rep [4]uint32
|
||||
// length when match will be accepted
|
||||
nAccept int
|
||||
// nodes to check
|
||||
check int
|
||||
// finish if length get shorter
|
||||
stopShorter bool
|
||||
}
|
||||
|
||||
func (t *binTree) match(m match, distIter func() (int, bool), p matchParams,
|
||||
) (r match, checked int, accepted bool) {
|
||||
buf := &t.dict.buf
|
||||
for {
|
||||
if checked >= p.check {
|
||||
return m, checked, true
|
||||
}
|
||||
dist, ok := distIter()
|
||||
if !ok {
|
||||
return m, checked, false
|
||||
}
|
||||
checked++
|
||||
if m.n > 0 {
|
||||
i := buf.rear - dist + m.n - 1
|
||||
if i < 0 {
|
||||
i += len(buf.data)
|
||||
} else if i >= len(buf.data) {
|
||||
i -= len(buf.data)
|
||||
}
|
||||
if buf.data[i] != t.data[m.n-1] {
|
||||
if p.stopShorter {
|
||||
return m, checked, false
|
||||
}
|
||||
continue
|
||||
}
|
||||
}
|
||||
n := buf.matchLen(dist, t.data)
|
||||
switch n {
|
||||
case 0:
|
||||
if p.stopShorter {
|
||||
return m, checked, false
|
||||
}
|
||||
continue
|
||||
case 1:
|
||||
if uint32(dist-minDistance) != p.rep[0] {
|
||||
continue
|
||||
}
|
||||
}
|
||||
if n < m.n || (n == m.n && int64(dist) >= m.distance) {
|
||||
continue
|
||||
}
|
||||
m = match{int64(dist), n}
|
||||
if n >= p.nAccept {
|
||||
return m, checked, true
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (t *binTree) NextOp(rep [4]uint32) operation {
|
||||
// retrieve maxMatchLen data
|
||||
n, _ := t.dict.buf.Peek(t.data[:maxMatchLen])
|
||||
if n == 0 {
|
||||
panic("no data in buffer")
|
||||
}
|
||||
t.data = t.data[:n]
|
||||
|
||||
var (
|
||||
m match
|
||||
x, u, v uint32
|
||||
iterPred, iterSucc func() (int, bool)
|
||||
)
|
||||
p := matchParams{
|
||||
rep: rep,
|
||||
nAccept: maxMatchLen,
|
||||
check: 32,
|
||||
}
|
||||
i := 4
|
||||
iterSmall := func() (dist int, ok bool) {
|
||||
i--
|
||||
if i <= 0 {
|
||||
return 0, false
|
||||
}
|
||||
return i, true
|
||||
}
|
||||
m, checked, accepted := t.match(m, iterSmall, p)
|
||||
if accepted {
|
||||
goto end
|
||||
}
|
||||
p.check -= checked
|
||||
x = xval(t.data)
|
||||
u, v = t.search(t.root, x)
|
||||
if u == v && len(t.data) == 4 {
|
||||
iter := func() (dist int, ok bool) {
|
||||
if u == null {
|
||||
return 0, false
|
||||
}
|
||||
dist = t.distance(u)
|
||||
u, v = t.search(t.node[u].l, x)
|
||||
if u != v {
|
||||
u = null
|
||||
}
|
||||
return dist, true
|
||||
}
|
||||
m, _, _ = t.match(m, iter, p)
|
||||
goto end
|
||||
}
|
||||
p.stopShorter = true
|
||||
iterSucc = func() (dist int, ok bool) {
|
||||
if v == null {
|
||||
return 0, false
|
||||
}
|
||||
dist = t.distance(v)
|
||||
v = t.succ(v)
|
||||
return dist, true
|
||||
}
|
||||
m, checked, accepted = t.match(m, iterSucc, p)
|
||||
if accepted {
|
||||
goto end
|
||||
}
|
||||
p.check -= checked
|
||||
iterPred = func() (dist int, ok bool) {
|
||||
if u == null {
|
||||
return 0, false
|
||||
}
|
||||
dist = t.distance(u)
|
||||
u = t.pred(u)
|
||||
return dist, true
|
||||
}
|
||||
m, _, _ = t.match(m, iterPred, p)
|
||||
end:
|
||||
if m.n == 0 {
|
||||
return lit{t.data[0]}
|
||||
}
|
||||
return m
|
||||
}
|
||||
-47
@@ -1,47 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
/* Naming conventions follows the CodeReviewComments in the Go Wiki. */
|
||||
|
||||
// ntz32Const is used by the functions NTZ and NLZ.
|
||||
const ntz32Const = 0x04d7651f
|
||||
|
||||
// ntz32Table is a helper table for de Bruijn algorithm by Danny Dubé.
|
||||
// See Henry S. Warren, Jr. "Hacker's Delight" section 5-1 figure 5-26.
|
||||
var ntz32Table = [32]int8{
|
||||
0, 1, 2, 24, 3, 19, 6, 25,
|
||||
22, 4, 20, 10, 16, 7, 12, 26,
|
||||
31, 23, 18, 5, 21, 9, 15, 11,
|
||||
30, 17, 8, 14, 29, 13, 28, 27,
|
||||
}
|
||||
|
||||
/*
|
||||
// ntz32 computes the number of trailing zeros for an unsigned 32-bit integer.
|
||||
func ntz32(x uint32) int {
|
||||
if x == 0 {
|
||||
return 32
|
||||
}
|
||||
x = (x & -x) * ntz32Const
|
||||
return int(ntz32Table[x>>27])
|
||||
}
|
||||
*/
|
||||
|
||||
// nlz32 computes the number of leading zeros for an unsigned 32-bit integer.
|
||||
func nlz32(x uint32) int {
|
||||
// Smear left most bit to the right
|
||||
x |= x >> 1
|
||||
x |= x >> 2
|
||||
x |= x >> 4
|
||||
x |= x >> 8
|
||||
x |= x >> 16
|
||||
// Use ntz mechanism to calculate nlz.
|
||||
x++
|
||||
if x == 0 {
|
||||
return 0
|
||||
}
|
||||
x *= ntz32Const
|
||||
return 32 - int(ntz32Table[x>>27])
|
||||
}
|
||||
-40
@@ -1,40 +0,0 @@
|
||||
// Copyright 2014-2022 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 (
|
||||
"io"
|
||||
)
|
||||
|
||||
// breader provides the ReadByte function for a Reader. It doesn't read
|
||||
// more data from the reader than absolutely necessary.
|
||||
type breader struct {
|
||||
io.Reader
|
||||
// helper slice to save allocations
|
||||
p []byte
|
||||
}
|
||||
|
||||
// ByteReader converts an io.Reader into an io.ByteReader.
|
||||
func ByteReader(r io.Reader) io.ByteReader {
|
||||
br, ok := r.(io.ByteReader)
|
||||
if !ok {
|
||||
return &breader{r, make([]byte, 1)}
|
||||
}
|
||||
return br
|
||||
}
|
||||
|
||||
// ReadByte read byte function.
|
||||
func (r *breader) ReadByte() (c byte, err error) {
|
||||
for i := 0; i < 100; i++ {
|
||||
n, err := r.Reader.Read(r.p)
|
||||
if n > 0 {
|
||||
return r.p[0], nil
|
||||
}
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
}
|
||||
return 0, io.ErrNoProgress
|
||||
}
|
||||
-171
@@ -1,171 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
// buffer provides a circular buffer of bytes. If the front index equals
|
||||
// the rear index the buffer is empty. As a consequence front cannot be
|
||||
// equal rear for a full buffer. So a full buffer has a length that is
|
||||
// one byte less the the length of the data slice.
|
||||
type buffer struct {
|
||||
data []byte
|
||||
front int
|
||||
rear int
|
||||
}
|
||||
|
||||
// newBuffer creates a buffer with the given size.
|
||||
func newBuffer(size int) *buffer {
|
||||
return &buffer{data: make([]byte, size+1)}
|
||||
}
|
||||
|
||||
// Cap returns the capacity of the buffer.
|
||||
func (b *buffer) Cap() int {
|
||||
return len(b.data) - 1
|
||||
}
|
||||
|
||||
// Resets the buffer. The front and rear index are set to zero.
|
||||
func (b *buffer) Reset() {
|
||||
b.front = 0
|
||||
b.rear = 0
|
||||
}
|
||||
|
||||
// Buffered returns the number of bytes buffered.
|
||||
func (b *buffer) Buffered() int {
|
||||
delta := b.front - b.rear
|
||||
if delta < 0 {
|
||||
delta += len(b.data)
|
||||
}
|
||||
return delta
|
||||
}
|
||||
|
||||
// Available returns the number of bytes available for writing.
|
||||
func (b *buffer) Available() int {
|
||||
delta := b.rear - 1 - b.front
|
||||
if delta < 0 {
|
||||
delta += len(b.data)
|
||||
}
|
||||
return delta
|
||||
}
|
||||
|
||||
// addIndex adds a non-negative integer to the index i and returns the
|
||||
// resulting index. The function takes care of wrapping the index as
|
||||
// well as potential overflow situations.
|
||||
func (b *buffer) addIndex(i int, n int) int {
|
||||
// subtraction of len(b.data) prevents overflow
|
||||
i += n - len(b.data)
|
||||
if i < 0 {
|
||||
i += len(b.data)
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
// Read reads bytes from the buffer into p and returns the number of
|
||||
// bytes read. The function never returns an error but might return less
|
||||
// data than requested.
|
||||
func (b *buffer) Read(p []byte) (n int, err error) {
|
||||
n, err = b.Peek(p)
|
||||
b.rear = b.addIndex(b.rear, n)
|
||||
return n, err
|
||||
}
|
||||
|
||||
// Peek reads bytes from the buffer into p without changing the buffer.
|
||||
// Peek will never return an error but might return less data than
|
||||
// requested.
|
||||
func (b *buffer) Peek(p []byte) (n int, err error) {
|
||||
m := b.Buffered()
|
||||
n = len(p)
|
||||
if m < n {
|
||||
n = m
|
||||
p = p[:n]
|
||||
}
|
||||
k := copy(p, b.data[b.rear:])
|
||||
if k < n {
|
||||
copy(p[k:], b.data)
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
// Discard skips the n next bytes to read from the buffer, returning the
|
||||
// bytes discarded.
|
||||
//
|
||||
// If Discards skips fewer than n bytes, it returns an error.
|
||||
func (b *buffer) Discard(n int) (discarded int, err error) {
|
||||
if n < 0 {
|
||||
return 0, errors.New("buffer.Discard: negative argument")
|
||||
}
|
||||
m := b.Buffered()
|
||||
if m < n {
|
||||
n = m
|
||||
err = errors.New(
|
||||
"buffer.Discard: discarded less bytes then requested")
|
||||
}
|
||||
b.rear = b.addIndex(b.rear, n)
|
||||
return n, err
|
||||
}
|
||||
|
||||
// ErrNoSpace indicates that there is insufficient space for the Write
|
||||
// operation.
|
||||
var ErrNoSpace = errors.New("insufficient space")
|
||||
|
||||
// Write puts data into the buffer. If less bytes are written than
|
||||
// requested ErrNoSpace is returned.
|
||||
func (b *buffer) Write(p []byte) (n int, err error) {
|
||||
m := b.Available()
|
||||
n = len(p)
|
||||
if m < n {
|
||||
n = m
|
||||
p = p[:m]
|
||||
err = ErrNoSpace
|
||||
}
|
||||
k := copy(b.data[b.front:], p)
|
||||
if k < n {
|
||||
copy(b.data, p[k:])
|
||||
}
|
||||
b.front = b.addIndex(b.front, n)
|
||||
return n, err
|
||||
}
|
||||
|
||||
// WriteByte writes a single byte into the buffer. The error ErrNoSpace
|
||||
// is returned if no single byte is available in the buffer for writing.
|
||||
func (b *buffer) WriteByte(c byte) error {
|
||||
if b.Available() < 1 {
|
||||
return ErrNoSpace
|
||||
}
|
||||
b.data[b.front] = c
|
||||
b.front = b.addIndex(b.front, 1)
|
||||
return nil
|
||||
}
|
||||
|
||||
// prefixLen returns the length of the common prefix of a and b.
|
||||
func prefixLen(a, b []byte) int {
|
||||
if len(a) > len(b) {
|
||||
a, b = b, a
|
||||
}
|
||||
for i, c := range a {
|
||||
if b[i] != c {
|
||||
return i
|
||||
}
|
||||
}
|
||||
return len(a)
|
||||
}
|
||||
|
||||
// matchLen returns the length of the common prefix for the given
|
||||
// distance from the rear and the byte slice p.
|
||||
func (b *buffer) matchLen(distance int, p []byte) int {
|
||||
var n int
|
||||
i := b.rear - distance
|
||||
if i < 0 {
|
||||
if n = prefixLen(p, b.data[len(b.data)+i:]); n < -i {
|
||||
return n
|
||||
}
|
||||
p = p[n:]
|
||||
i = 0
|
||||
}
|
||||
n += prefixLen(p, b.data[i:])
|
||||
return n
|
||||
}
|
||||
-37
@@ -1,37 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
"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
|
||||
}
|
||||
-277
@@ -1,277 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
// decoder decodes a raw LZMA stream without any header.
|
||||
type decoder struct {
|
||||
// dictionary; the rear pointer of the buffer will be used for
|
||||
// reading the data.
|
||||
Dict *decoderDict
|
||||
// decoder state
|
||||
State *state
|
||||
// range decoder
|
||||
rd *rangeDecoder
|
||||
// start stores the head value of the dictionary for the LZMA
|
||||
// stream
|
||||
start int64
|
||||
// size of uncompressed data
|
||||
size int64
|
||||
// end-of-stream encountered
|
||||
eos bool
|
||||
// EOS marker found
|
||||
eosMarker bool
|
||||
}
|
||||
|
||||
// newDecoder creates a new decoder instance. The parameter size provides
|
||||
// the expected byte size of the decompressed data. If the size is
|
||||
// unknown use a negative value. In that case the decoder will look for
|
||||
// a terminating end-of-stream marker.
|
||||
func newDecoder(br io.ByteReader, state *state, dict *decoderDict, size int64) (d *decoder, err error) {
|
||||
rd, err := newRangeDecoder(br)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
d = &decoder{
|
||||
State: state,
|
||||
Dict: dict,
|
||||
rd: rd,
|
||||
size: size,
|
||||
start: dict.pos(),
|
||||
}
|
||||
return d, nil
|
||||
}
|
||||
|
||||
// Reopen restarts the decoder with a new byte reader and a new size. Reopen
|
||||
// resets the Decompressed counter to zero.
|
||||
func (d *decoder) Reopen(br io.ByteReader, size int64) error {
|
||||
var err error
|
||||
if d.rd, err = newRangeDecoder(br); err != nil {
|
||||
return err
|
||||
}
|
||||
d.start = d.Dict.pos()
|
||||
d.size = size
|
||||
d.eos = false
|
||||
return nil
|
||||
}
|
||||
|
||||
// decodeLiteral decodes a single literal from the LZMA stream.
|
||||
func (d *decoder) decodeLiteral() (op operation, err error) {
|
||||
litState := d.State.litState(d.Dict.byteAt(1), d.Dict.head)
|
||||
match := d.Dict.byteAt(int(d.State.rep[0]) + 1)
|
||||
s, err := d.State.litCodec.Decode(d.rd, d.State.state, match, litState)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return lit{s}, nil
|
||||
}
|
||||
|
||||
// errEOS indicates that an EOS marker has been found.
|
||||
var errEOS = errors.New("EOS marker found")
|
||||
|
||||
// readOp decodes the next operation from the compressed stream. It
|
||||
// returns the operation. If an explicit end of stream marker is
|
||||
// identified the eos error is returned.
|
||||
func (d *decoder) readOp() (op operation, err error) {
|
||||
// Value of the end of stream (EOS) marker
|
||||
const eosDist = 1<<32 - 1
|
||||
|
||||
state, state2, posState := d.State.states(d.Dict.head)
|
||||
|
||||
b, err := d.State.isMatch[state2].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b == 0 {
|
||||
// literal
|
||||
op, err := d.decodeLiteral()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
d.State.updateStateLiteral()
|
||||
return op, nil
|
||||
}
|
||||
b, err = d.State.isRep[state].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b == 0 {
|
||||
// simple match
|
||||
d.State.rep[3], d.State.rep[2], d.State.rep[1] =
|
||||
d.State.rep[2], d.State.rep[1], d.State.rep[0]
|
||||
|
||||
d.State.updateStateMatch()
|
||||
// The length decoder returns the length offset.
|
||||
n, err := d.State.lenCodec.Decode(d.rd, posState)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
// The dist decoder returns the distance offset. The actual
|
||||
// distance is 1 higher.
|
||||
d.State.rep[0], err = d.State.distCodec.Decode(d.rd, n)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if d.State.rep[0] == eosDist {
|
||||
d.eosMarker = true
|
||||
return nil, errEOS
|
||||
}
|
||||
op = match{n: int(n) + minMatchLen,
|
||||
distance: int64(d.State.rep[0]) + minDistance}
|
||||
return op, nil
|
||||
}
|
||||
b, err = d.State.isRepG0[state].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
dist := d.State.rep[0]
|
||||
if b == 0 {
|
||||
// rep match 0
|
||||
b, err = d.State.isRepG0Long[state2].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b == 0 {
|
||||
d.State.updateStateShortRep()
|
||||
op = match{n: 1, distance: int64(dist) + minDistance}
|
||||
return op, nil
|
||||
}
|
||||
} else {
|
||||
b, err = d.State.isRepG1[state].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b == 0 {
|
||||
dist = d.State.rep[1]
|
||||
} else {
|
||||
b, err = d.State.isRepG2[state].Decode(d.rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b == 0 {
|
||||
dist = d.State.rep[2]
|
||||
} else {
|
||||
dist = d.State.rep[3]
|
||||
d.State.rep[3] = d.State.rep[2]
|
||||
}
|
||||
d.State.rep[2] = d.State.rep[1]
|
||||
}
|
||||
d.State.rep[1] = d.State.rep[0]
|
||||
d.State.rep[0] = dist
|
||||
}
|
||||
n, err := d.State.repLenCodec.Decode(d.rd, posState)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
d.State.updateStateRep()
|
||||
op = match{n: int(n) + minMatchLen, distance: int64(dist) + minDistance}
|
||||
return op, nil
|
||||
}
|
||||
|
||||
// apply takes the operation and transforms the decoder dictionary accordingly.
|
||||
func (d *decoder) apply(op operation) error {
|
||||
var err error
|
||||
switch x := op.(type) {
|
||||
case match:
|
||||
err = d.Dict.writeMatch(x.distance, x.n)
|
||||
case lit:
|
||||
err = d.Dict.WriteByte(x.b)
|
||||
default:
|
||||
panic("op is neither a match nor a literal")
|
||||
}
|
||||
return err
|
||||
}
|
||||
|
||||
// decompress fills the dictionary unless no space for new data is
|
||||
// available. If the end of the LZMA stream has been reached io.EOF will
|
||||
// be returned.
|
||||
func (d *decoder) decompress() error {
|
||||
if d.eos {
|
||||
return io.EOF
|
||||
}
|
||||
for d.Dict.Available() >= maxMatchLen {
|
||||
op, err := d.readOp()
|
||||
switch err {
|
||||
case nil:
|
||||
// break
|
||||
case errEOS:
|
||||
d.eos = true
|
||||
if !d.rd.possiblyAtEnd() {
|
||||
return errDataAfterEOS
|
||||
}
|
||||
if d.size >= 0 && d.size != d.Decompressed() {
|
||||
return errSize
|
||||
}
|
||||
return io.EOF
|
||||
case io.EOF:
|
||||
d.eos = true
|
||||
return io.ErrUnexpectedEOF
|
||||
default:
|
||||
return err
|
||||
}
|
||||
if err = d.apply(op); err != nil {
|
||||
return err
|
||||
}
|
||||
if d.size >= 0 && d.Decompressed() >= d.size {
|
||||
d.eos = true
|
||||
if d.Decompressed() > d.size {
|
||||
return errSize
|
||||
}
|
||||
if !d.rd.possiblyAtEnd() {
|
||||
switch _, err = d.readOp(); err {
|
||||
case nil:
|
||||
return errSize
|
||||
case io.EOF:
|
||||
return io.ErrUnexpectedEOF
|
||||
case errEOS:
|
||||
break
|
||||
default:
|
||||
return err
|
||||
}
|
||||
}
|
||||
return io.EOF
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Errors that may be returned while decoding data.
|
||||
var (
|
||||
errDataAfterEOS = errors.New("lzma: data after end of stream marker")
|
||||
errSize = errors.New("lzma: wrong uncompressed data size")
|
||||
)
|
||||
|
||||
// Read reads data from the buffer. If no more data is available io.EOF is
|
||||
// returned.
|
||||
func (d *decoder) Read(p []byte) (n int, err error) {
|
||||
var k int
|
||||
for {
|
||||
// Read of decoder dict never returns an error.
|
||||
k, err = d.Dict.Read(p[n:])
|
||||
if err != nil {
|
||||
panic(fmt.Errorf("dictionary read error %s", err))
|
||||
}
|
||||
if k == 0 && d.eos {
|
||||
return n, io.EOF
|
||||
}
|
||||
n += k
|
||||
if n >= len(p) {
|
||||
return n, nil
|
||||
}
|
||||
if err = d.decompress(); err != nil && err != io.EOF {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Decompressed returns the number of bytes decompressed by the decoder.
|
||||
func (d *decoder) Decompressed() int64 {
|
||||
return d.Dict.pos() - d.start
|
||||
}
|
||||
-128
@@ -1,128 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
// decoderDict provides the dictionary for the decoder. The whole
|
||||
// dictionary is used as reader buffer.
|
||||
type decoderDict struct {
|
||||
buf buffer
|
||||
head int64
|
||||
}
|
||||
|
||||
// newDecoderDict creates a new decoder dictionary. The whole dictionary
|
||||
// will be used as reader buffer.
|
||||
func newDecoderDict(dictCap int) (d *decoderDict, err error) {
|
||||
// lower limit supports easy test cases
|
||||
if !(1 <= dictCap && int64(dictCap) <= MaxDictCap) {
|
||||
return nil, errors.New("lzma: dictCap out of range")
|
||||
}
|
||||
d = &decoderDict{buf: *newBuffer(dictCap)}
|
||||
return d, nil
|
||||
}
|
||||
|
||||
// Reset clears the dictionary. The read buffer is not changed, so the
|
||||
// buffered data can still be read.
|
||||
func (d *decoderDict) Reset() {
|
||||
d.head = 0
|
||||
}
|
||||
|
||||
// WriteByte writes a single byte into the dictionary. It is used to
|
||||
// write literals into the dictionary.
|
||||
func (d *decoderDict) WriteByte(c byte) error {
|
||||
if err := d.buf.WriteByte(c); err != nil {
|
||||
return err
|
||||
}
|
||||
d.head++
|
||||
return nil
|
||||
}
|
||||
|
||||
// pos returns the position of the dictionary head.
|
||||
func (d *decoderDict) pos() int64 { return d.head }
|
||||
|
||||
// dictLen returns the actual length of the dictionary.
|
||||
func (d *decoderDict) dictLen() int {
|
||||
capacity := d.buf.Cap()
|
||||
if d.head >= int64(capacity) {
|
||||
return capacity
|
||||
}
|
||||
return int(d.head)
|
||||
}
|
||||
|
||||
// byteAt returns a byte stored in the dictionary. If the distance is
|
||||
// non-positive or exceeds the current length of the dictionary the zero
|
||||
// byte is returned.
|
||||
func (d *decoderDict) byteAt(dist int) byte {
|
||||
if !(0 < dist && dist <= d.dictLen()) {
|
||||
return 0
|
||||
}
|
||||
i := d.buf.front - dist
|
||||
if i < 0 {
|
||||
i += len(d.buf.data)
|
||||
}
|
||||
return d.buf.data[i]
|
||||
}
|
||||
|
||||
// writeMatch writes the match at the top of the dictionary. The given
|
||||
// distance must point in the current dictionary and the length must not
|
||||
// exceed the maximum length 273 supported in LZMA.
|
||||
//
|
||||
// The error value ErrNoSpace indicates that no space is available in
|
||||
// the dictionary for writing. You need to read from the dictionary
|
||||
// first.
|
||||
func (d *decoderDict) writeMatch(dist int64, length int) error {
|
||||
if !(0 < dist && dist <= int64(d.dictLen())) {
|
||||
return errors.New("writeMatch: distance out of range")
|
||||
}
|
||||
if !(0 < length && length <= maxMatchLen) {
|
||||
return errors.New("writeMatch: length out of range")
|
||||
}
|
||||
if length > d.buf.Available() {
|
||||
return ErrNoSpace
|
||||
}
|
||||
d.head += int64(length)
|
||||
|
||||
i := d.buf.front - int(dist)
|
||||
if i < 0 {
|
||||
i += len(d.buf.data)
|
||||
}
|
||||
for length > 0 {
|
||||
var p []byte
|
||||
if i >= d.buf.front {
|
||||
p = d.buf.data[i:]
|
||||
i = 0
|
||||
} else {
|
||||
p = d.buf.data[i:d.buf.front]
|
||||
i = d.buf.front
|
||||
}
|
||||
if len(p) > length {
|
||||
p = p[:length]
|
||||
}
|
||||
if _, err := d.buf.Write(p); err != nil {
|
||||
panic(fmt.Errorf("d.buf.Write returned error %s", err))
|
||||
}
|
||||
length -= len(p)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Write writes the given bytes into the dictionary and advances the
|
||||
// head.
|
||||
func (d *decoderDict) Write(p []byte) (n int, err error) {
|
||||
n, err = d.buf.Write(p)
|
||||
d.head += int64(n)
|
||||
return n, err
|
||||
}
|
||||
|
||||
// Available returns the number of available bytes for writing into the
|
||||
// decoder dictionary.
|
||||
func (d *decoderDict) Available() int { return d.buf.Available() }
|
||||
|
||||
// Read reads data from the buffer contained in the decoder dictionary.
|
||||
func (d *decoderDict) Read(p []byte) (n int, err error) { return d.buf.Read(p) }
|
||||
-38
@@ -1,38 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// directCodec allows the encoding and decoding of values with a fixed number
|
||||
// of bits. The number of bits must be in the range [1,32].
|
||||
type directCodec byte
|
||||
|
||||
// Bits returns the number of bits supported by this codec.
|
||||
func (dc directCodec) Bits() int {
|
||||
return int(dc)
|
||||
}
|
||||
|
||||
// Encode uses the range encoder to encode a value with the fixed number of
|
||||
// bits. The most-significant bit is encoded first.
|
||||
func (dc directCodec) Encode(e *rangeEncoder, v uint32) error {
|
||||
for i := int(dc) - 1; i >= 0; i-- {
|
||||
if err := e.DirectEncodeBit(v >> uint(i)); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decode uses the range decoder to decode a value with the given number of
|
||||
// given bits. The most-significant bit is decoded first.
|
||||
func (dc directCodec) Decode(d *rangeDecoder) (v uint32, err error) {
|
||||
for i := int(dc) - 1; i >= 0; i-- {
|
||||
x, err := d.DirectDecodeBit()
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
v = (v << 1) | x
|
||||
}
|
||||
return v, nil
|
||||
}
|
||||
-140
@@ -1,140 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// Constants used by the distance codec.
|
||||
const (
|
||||
// minimum supported distance
|
||||
minDistance = 1
|
||||
// maximum supported distance, value is used for the eos marker.
|
||||
maxDistance = 1 << 32
|
||||
// number of the supported len states
|
||||
lenStates = 4
|
||||
// start for the position models
|
||||
startPosModel = 4
|
||||
// first index with align bits support
|
||||
endPosModel = 14
|
||||
// bits for the position slots
|
||||
posSlotBits = 6
|
||||
// number of align bits
|
||||
alignBits = 4
|
||||
)
|
||||
|
||||
// distCodec provides encoding and decoding of distance values.
|
||||
type distCodec struct {
|
||||
posSlotCodecs [lenStates]treeCodec
|
||||
posModel [endPosModel - startPosModel]treeReverseCodec
|
||||
alignCodec treeReverseCodec
|
||||
}
|
||||
|
||||
// deepcopy initializes dc as deep copy of the source.
|
||||
func (dc *distCodec) deepcopy(src *distCodec) {
|
||||
if dc == src {
|
||||
return
|
||||
}
|
||||
for i := range dc.posSlotCodecs {
|
||||
dc.posSlotCodecs[i].deepcopy(&src.posSlotCodecs[i])
|
||||
}
|
||||
for i := range dc.posModel {
|
||||
dc.posModel[i].deepcopy(&src.posModel[i])
|
||||
}
|
||||
dc.alignCodec.deepcopy(&src.alignCodec)
|
||||
}
|
||||
|
||||
// newDistCodec creates a new distance codec.
|
||||
func (dc *distCodec) init() {
|
||||
for i := range dc.posSlotCodecs {
|
||||
dc.posSlotCodecs[i] = makeTreeCodec(posSlotBits)
|
||||
}
|
||||
for i := range dc.posModel {
|
||||
posSlot := startPosModel + i
|
||||
bits := (posSlot >> 1) - 1
|
||||
dc.posModel[i] = makeTreeReverseCodec(bits)
|
||||
}
|
||||
dc.alignCodec = makeTreeReverseCodec(alignBits)
|
||||
}
|
||||
|
||||
// lenState converts the value l to a supported lenState value.
|
||||
func lenState(l uint32) uint32 {
|
||||
if l >= lenStates {
|
||||
l = lenStates - 1
|
||||
}
|
||||
return l
|
||||
}
|
||||
|
||||
// Encode encodes the distance using the parameter l. Dist can have values from
|
||||
// the full range of uint32 values. To get the distance offset the actual match
|
||||
// distance has to be decreased by 1. A distance offset of 0xffffffff (eos)
|
||||
// indicates the end of the stream.
|
||||
func (dc *distCodec) Encode(e *rangeEncoder, dist uint32, l uint32) (err error) {
|
||||
// Compute the posSlot using nlz32
|
||||
var posSlot uint32
|
||||
var bits uint32
|
||||
if dist < startPosModel {
|
||||
posSlot = dist
|
||||
} else {
|
||||
bits = uint32(30 - nlz32(dist))
|
||||
posSlot = startPosModel - 2 + (bits << 1)
|
||||
posSlot += (dist >> uint(bits)) & 1
|
||||
}
|
||||
|
||||
if err = dc.posSlotCodecs[lenState(l)].Encode(e, posSlot); err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
switch {
|
||||
case posSlot < startPosModel:
|
||||
return nil
|
||||
case posSlot < endPosModel:
|
||||
tc := &dc.posModel[posSlot-startPosModel]
|
||||
return tc.Encode(dist, e)
|
||||
}
|
||||
dic := directCodec(bits - alignBits)
|
||||
if err = dic.Encode(e, dist>>alignBits); err != nil {
|
||||
return
|
||||
}
|
||||
return dc.alignCodec.Encode(dist, e)
|
||||
}
|
||||
|
||||
// Decode decodes the distance offset using the parameter l. The dist value
|
||||
// 0xffffffff (eos) indicates the end of the stream. Add one to the distance
|
||||
// offset to get the actual match distance.
|
||||
func (dc *distCodec) Decode(d *rangeDecoder, l uint32) (dist uint32, err error) {
|
||||
posSlot, err := dc.posSlotCodecs[lenState(l)].Decode(d)
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
// posSlot equals distance
|
||||
if posSlot < startPosModel {
|
||||
return posSlot, nil
|
||||
}
|
||||
|
||||
// posSlot uses the individual models
|
||||
bits := (posSlot >> 1) - 1
|
||||
dist = (2 | (posSlot & 1)) << bits
|
||||
var u uint32
|
||||
if posSlot < endPosModel {
|
||||
tc := &dc.posModel[posSlot-startPosModel]
|
||||
if u, err = tc.Decode(d); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
dist += u
|
||||
return dist, nil
|
||||
}
|
||||
|
||||
// posSlots use direct encoding and a single model for the four align
|
||||
// bits.
|
||||
dic := directCodec(bits - alignBits)
|
||||
if u, err = dic.Decode(d); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
dist += u << alignBits
|
||||
if u, err = dc.alignCodec.Decode(d); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
dist += u
|
||||
return dist, nil
|
||||
}
|
||||
-268
@@ -1,268 +0,0 @@
|
||||
// Copyright 2014-2022 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 (
|
||||
"fmt"
|
||||
"io"
|
||||
)
|
||||
|
||||
// opLenMargin provides the upper limit of the number of bytes required
|
||||
// to encode a single operation.
|
||||
const opLenMargin = 16
|
||||
|
||||
// compressFlags control the compression process.
|
||||
type compressFlags uint32
|
||||
|
||||
// Values for compressFlags.
|
||||
const (
|
||||
// all data should be compressed, even if compression is not
|
||||
// optimal.
|
||||
all compressFlags = 1 << iota
|
||||
)
|
||||
|
||||
// encoderFlags provide the flags for an encoder.
|
||||
type encoderFlags uint32
|
||||
|
||||
// Flags for the encoder.
|
||||
const (
|
||||
// eosMarker requests an EOS marker to be written.
|
||||
eosMarker encoderFlags = 1 << iota
|
||||
)
|
||||
|
||||
// Encoder compresses data buffered in the encoder dictionary and writes
|
||||
// it into a byte writer.
|
||||
type encoder struct {
|
||||
dict *encoderDict
|
||||
state *state
|
||||
re *rangeEncoder
|
||||
start int64
|
||||
// generate eos marker
|
||||
marker bool
|
||||
limit bool
|
||||
margin int
|
||||
}
|
||||
|
||||
// newEncoder creates a new encoder. If the byte writer must be
|
||||
// limited use LimitedByteWriter provided by this package. The flags
|
||||
// argument supports the eosMarker flag, controlling whether a
|
||||
// terminating end-of-stream marker must be written.
|
||||
func newEncoder(bw io.ByteWriter, state *state, dict *encoderDict,
|
||||
flags encoderFlags) (e *encoder, err error) {
|
||||
|
||||
re, err := newRangeEncoder(bw)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
e = &encoder{
|
||||
dict: dict,
|
||||
state: state,
|
||||
re: re,
|
||||
marker: flags&eosMarker != 0,
|
||||
start: dict.Pos(),
|
||||
margin: opLenMargin,
|
||||
}
|
||||
if e.marker {
|
||||
e.margin += 5
|
||||
}
|
||||
return e, nil
|
||||
}
|
||||
|
||||
// Write writes the bytes from p into the dictionary. If not enough
|
||||
// space is available the data in the dictionary buffer will be
|
||||
// compressed to make additional space available. If the limit of the
|
||||
// underlying writer has been reached ErrLimit will be returned.
|
||||
func (e *encoder) Write(p []byte) (n int, err error) {
|
||||
for {
|
||||
k, err := e.dict.Write(p[n:])
|
||||
n += k
|
||||
if err == ErrNoSpace {
|
||||
if err = e.compress(0); err != nil {
|
||||
return n, err
|
||||
}
|
||||
continue
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
|
||||
// Reopen reopens the encoder with a new byte writer.
|
||||
func (e *encoder) Reopen(bw io.ByteWriter) error {
|
||||
var err error
|
||||
if e.re, err = newRangeEncoder(bw); err != nil {
|
||||
return err
|
||||
}
|
||||
e.start = e.dict.Pos()
|
||||
e.limit = false
|
||||
return nil
|
||||
}
|
||||
|
||||
// writeLiteral writes a literal into the LZMA stream
|
||||
func (e *encoder) writeLiteral(l lit) error {
|
||||
var err error
|
||||
state, state2, _ := e.state.states(e.dict.Pos())
|
||||
if err = e.state.isMatch[state2].Encode(e.re, 0); err != nil {
|
||||
return err
|
||||
}
|
||||
litState := e.state.litState(e.dict.ByteAt(1), e.dict.Pos())
|
||||
match := e.dict.ByteAt(int(e.state.rep[0]) + 1)
|
||||
err = e.state.litCodec.Encode(e.re, l.b, state, match, litState)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
e.state.updateStateLiteral()
|
||||
return nil
|
||||
}
|
||||
|
||||
// iverson implements the Iverson operator as proposed by Donald Knuth in his
|
||||
// book Concrete Mathematics.
|
||||
func iverson(ok bool) uint32 {
|
||||
if ok {
|
||||
return 1
|
||||
}
|
||||
return 0
|
||||
}
|
||||
|
||||
// writeMatch writes a repetition operation into the operation stream
|
||||
func (e *encoder) writeMatch(m match) error {
|
||||
var err error
|
||||
if !(minDistance <= m.distance && m.distance <= maxDistance) {
|
||||
panic(fmt.Errorf("match distance %d out of range", m.distance))
|
||||
}
|
||||
dist := uint32(m.distance - minDistance)
|
||||
if !(minMatchLen <= m.n && m.n <= maxMatchLen) &&
|
||||
!(dist == e.state.rep[0] && m.n == 1) {
|
||||
panic(fmt.Errorf(
|
||||
"match length %d out of range; dist %d rep[0] %d",
|
||||
m.n, dist, e.state.rep[0]))
|
||||
}
|
||||
state, state2, posState := e.state.states(e.dict.Pos())
|
||||
if err = e.state.isMatch[state2].Encode(e.re, 1); err != nil {
|
||||
return err
|
||||
}
|
||||
g := 0
|
||||
for ; g < 4; g++ {
|
||||
if e.state.rep[g] == dist {
|
||||
break
|
||||
}
|
||||
}
|
||||
b := iverson(g < 4)
|
||||
if err = e.state.isRep[state].Encode(e.re, b); err != nil {
|
||||
return err
|
||||
}
|
||||
n := uint32(m.n - minMatchLen)
|
||||
if b == 0 {
|
||||
// simple match
|
||||
e.state.rep[3], e.state.rep[2], e.state.rep[1], e.state.rep[0] =
|
||||
e.state.rep[2], e.state.rep[1], e.state.rep[0], dist
|
||||
e.state.updateStateMatch()
|
||||
if err = e.state.lenCodec.Encode(e.re, n, posState); err != nil {
|
||||
return err
|
||||
}
|
||||
return e.state.distCodec.Encode(e.re, dist, n)
|
||||
}
|
||||
b = iverson(g != 0)
|
||||
if err = e.state.isRepG0[state].Encode(e.re, b); err != nil {
|
||||
return err
|
||||
}
|
||||
if b == 0 {
|
||||
// g == 0
|
||||
b = iverson(m.n != 1)
|
||||
if err = e.state.isRepG0Long[state2].Encode(e.re, b); err != nil {
|
||||
return err
|
||||
}
|
||||
if b == 0 {
|
||||
e.state.updateStateShortRep()
|
||||
return nil
|
||||
}
|
||||
} else {
|
||||
// g in {1,2,3}
|
||||
b = iverson(g != 1)
|
||||
if err = e.state.isRepG1[state].Encode(e.re, b); err != nil {
|
||||
return err
|
||||
}
|
||||
if b == 1 {
|
||||
// g in {2,3}
|
||||
b = iverson(g != 2)
|
||||
err = e.state.isRepG2[state].Encode(e.re, b)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if b == 1 {
|
||||
e.state.rep[3] = e.state.rep[2]
|
||||
}
|
||||
e.state.rep[2] = e.state.rep[1]
|
||||
}
|
||||
e.state.rep[1] = e.state.rep[0]
|
||||
e.state.rep[0] = dist
|
||||
}
|
||||
e.state.updateStateRep()
|
||||
return e.state.repLenCodec.Encode(e.re, n, posState)
|
||||
}
|
||||
|
||||
// writeOp writes a single operation to the range encoder. The function
|
||||
// checks whether there is enough space available to close the LZMA
|
||||
// stream.
|
||||
func (e *encoder) writeOp(op operation) error {
|
||||
if e.re.Available() < int64(e.margin) {
|
||||
return ErrLimit
|
||||
}
|
||||
switch x := op.(type) {
|
||||
case lit:
|
||||
return e.writeLiteral(x)
|
||||
case match:
|
||||
return e.writeMatch(x)
|
||||
default:
|
||||
panic("unexpected operation")
|
||||
}
|
||||
}
|
||||
|
||||
// compress compressed data from the dictionary buffer. If the flag all
|
||||
// is set, all data in the dictionary buffer will be compressed. The
|
||||
// function returns ErrLimit if the underlying writer has reached its
|
||||
// limit.
|
||||
func (e *encoder) compress(flags compressFlags) error {
|
||||
n := 0
|
||||
if flags&all == 0 {
|
||||
n = maxMatchLen - 1
|
||||
}
|
||||
d := e.dict
|
||||
m := d.m
|
||||
for d.Buffered() > n {
|
||||
op := m.NextOp(e.state.rep)
|
||||
if err := e.writeOp(op); err != nil {
|
||||
return err
|
||||
}
|
||||
d.Discard(op.Len())
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// eosMatch is a pseudo operation that indicates the end of the stream.
|
||||
var eosMatch = match{distance: maxDistance, n: minMatchLen}
|
||||
|
||||
// Close terminates the LZMA stream. If requested the end-of-stream
|
||||
// marker will be written. If the byte writer limit has been or will be
|
||||
// reached during compression of the remaining data in the buffer the
|
||||
// LZMA stream will be closed and data will remain in the buffer.
|
||||
func (e *encoder) Close() error {
|
||||
err := e.compress(all)
|
||||
if err != nil && err != ErrLimit {
|
||||
return err
|
||||
}
|
||||
if e.marker {
|
||||
if err := e.writeMatch(eosMatch); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
err = e.re.Close()
|
||||
return err
|
||||
}
|
||||
|
||||
// Compressed returns the number bytes of the input data that been
|
||||
// compressed.
|
||||
func (e *encoder) Compressed() int64 {
|
||||
return e.dict.Pos() - e.start
|
||||
}
|
||||
-149
@@ -1,149 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
// additional 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() }
|
||||
BIN
Binary file not shown.
-309
@@ -1,309 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
|
||||
"github.com/ulikunitz/xz/internal/hash"
|
||||
)
|
||||
|
||||
/* For compression we need to find byte sequences that match the byte
|
||||
* sequence at the dictionary head. A hash table is a simple method to
|
||||
* provide this capability.
|
||||
*/
|
||||
|
||||
// maxMatches limits the number of matches requested from the Matches
|
||||
// function. This controls the speed of the overall encoding.
|
||||
const maxMatches = 16
|
||||
|
||||
// shortDists defines the number of short distances supported by the
|
||||
// implementation.
|
||||
const shortDists = 8
|
||||
|
||||
// The minimum is somehow arbitrary but the maximum is limited by the
|
||||
// memory requirements of the hash table.
|
||||
const (
|
||||
minTableExponent = 9
|
||||
maxTableExponent = 20
|
||||
)
|
||||
|
||||
// newRoller contains the function used to create an instance of the
|
||||
// hash.Roller.
|
||||
var newRoller = func(n int) hash.Roller { return hash.NewCyclicPoly(n) }
|
||||
|
||||
// hashTable stores the hash table including the rolling hash method.
|
||||
//
|
||||
// We implement chained hashing into a circular buffer. Each entry in
|
||||
// the circular buffer stores the delta distance to the next position with a
|
||||
// word that has the same hash value.
|
||||
type hashTable struct {
|
||||
dict *encoderDict
|
||||
// actual hash table
|
||||
t []int64
|
||||
// circular list data with the offset to the next word
|
||||
data []uint32
|
||||
front int
|
||||
// mask for computing the index for the hash table
|
||||
mask uint64
|
||||
// hash offset; initial value is -int64(wordLen)
|
||||
hoff int64
|
||||
// length of the hashed word
|
||||
wordLen int
|
||||
// hash roller for computing the hash values for the Write
|
||||
// method
|
||||
wr hash.Roller
|
||||
// hash roller for computing arbitrary hashes
|
||||
hr hash.Roller
|
||||
// preallocated slices
|
||||
p [maxMatches]int64
|
||||
distances [maxMatches + shortDists]int
|
||||
}
|
||||
|
||||
// hashTableExponent derives the hash table exponent from the dictionary
|
||||
// capacity.
|
||||
func hashTableExponent(n uint32) int {
|
||||
e := 30 - nlz32(n)
|
||||
switch {
|
||||
case e < minTableExponent:
|
||||
e = minTableExponent
|
||||
case e > maxTableExponent:
|
||||
e = maxTableExponent
|
||||
}
|
||||
return e
|
||||
}
|
||||
|
||||
// newHashTable creates a new hash table for words of length wordLen
|
||||
func newHashTable(capacity int, wordLen int) (t *hashTable, err error) {
|
||||
if !(0 < capacity) {
|
||||
return nil, errors.New(
|
||||
"newHashTable: capacity must not be negative")
|
||||
}
|
||||
exp := hashTableExponent(uint32(capacity))
|
||||
if !(1 <= wordLen && wordLen <= 4) {
|
||||
return nil, errors.New("newHashTable: " +
|
||||
"argument wordLen out of range")
|
||||
}
|
||||
n := 1 << uint(exp)
|
||||
if n <= 0 {
|
||||
panic("newHashTable: exponent is too large")
|
||||
}
|
||||
t = &hashTable{
|
||||
t: make([]int64, n),
|
||||
data: make([]uint32, capacity),
|
||||
mask: (uint64(1) << uint(exp)) - 1,
|
||||
hoff: -int64(wordLen),
|
||||
wordLen: wordLen,
|
||||
wr: newRoller(wordLen),
|
||||
hr: newRoller(wordLen),
|
||||
}
|
||||
return t, nil
|
||||
}
|
||||
|
||||
func (t *hashTable) SetDict(d *encoderDict) { t.dict = d }
|
||||
|
||||
// buffered returns the number of bytes that are currently hashed.
|
||||
func (t *hashTable) buffered() int {
|
||||
n := t.hoff + 1
|
||||
switch {
|
||||
case n <= 0:
|
||||
return 0
|
||||
case n >= int64(len(t.data)):
|
||||
return len(t.data)
|
||||
}
|
||||
return int(n)
|
||||
}
|
||||
|
||||
// addIndex adds n to an index ensuring that is stays inside the
|
||||
// circular buffer for the hash chain.
|
||||
func (t *hashTable) addIndex(i, n int) int {
|
||||
i += n - len(t.data)
|
||||
if i < 0 {
|
||||
i += len(t.data)
|
||||
}
|
||||
return i
|
||||
}
|
||||
|
||||
// putDelta puts the delta instance at the current front of the circular
|
||||
// chain buffer.
|
||||
func (t *hashTable) putDelta(delta uint32) {
|
||||
t.data[t.front] = delta
|
||||
t.front = t.addIndex(t.front, 1)
|
||||
}
|
||||
|
||||
// putEntry puts a new entry into the hash table. If there is already a
|
||||
// value stored it is moved into the circular chain buffer.
|
||||
func (t *hashTable) putEntry(h uint64, pos int64) {
|
||||
if pos < 0 {
|
||||
return
|
||||
}
|
||||
i := h & t.mask
|
||||
old := t.t[i] - 1
|
||||
t.t[i] = pos + 1
|
||||
var delta int64
|
||||
if old >= 0 {
|
||||
delta = pos - old
|
||||
if delta > 1<<32-1 || delta > int64(t.buffered()) {
|
||||
delta = 0
|
||||
}
|
||||
}
|
||||
t.putDelta(uint32(delta))
|
||||
}
|
||||
|
||||
// WriteByte converts a single byte into a hash and puts them into the hash
|
||||
// table.
|
||||
func (t *hashTable) WriteByte(b byte) error {
|
||||
h := t.wr.RollByte(b)
|
||||
t.hoff++
|
||||
t.putEntry(h, t.hoff)
|
||||
return nil
|
||||
}
|
||||
|
||||
// Write converts the bytes provided into hash tables and stores the
|
||||
// abbreviated offsets into the hash table. The method will never return an
|
||||
// error.
|
||||
func (t *hashTable) Write(p []byte) (n int, err error) {
|
||||
for _, b := range p {
|
||||
// WriteByte doesn't generate an error.
|
||||
t.WriteByte(b)
|
||||
}
|
||||
return len(p), nil
|
||||
}
|
||||
|
||||
// getMatches the matches for a specific hash. The functions returns the
|
||||
// number of positions found.
|
||||
//
|
||||
// TODO: Make a getDistances because that we are actually interested in.
|
||||
func (t *hashTable) getMatches(h uint64, positions []int64) (n int) {
|
||||
if t.hoff < 0 || len(positions) == 0 {
|
||||
return 0
|
||||
}
|
||||
buffered := t.buffered()
|
||||
tailPos := t.hoff + 1 - int64(buffered)
|
||||
rear := t.front - buffered
|
||||
if rear >= 0 {
|
||||
rear -= len(t.data)
|
||||
}
|
||||
// get the slot for the hash
|
||||
pos := t.t[h&t.mask] - 1
|
||||
delta := pos - tailPos
|
||||
for {
|
||||
if delta < 0 {
|
||||
return n
|
||||
}
|
||||
positions[n] = tailPos + delta
|
||||
n++
|
||||
if n >= len(positions) {
|
||||
return n
|
||||
}
|
||||
i := rear + int(delta)
|
||||
if i < 0 {
|
||||
i += len(t.data)
|
||||
}
|
||||
u := t.data[i]
|
||||
if u == 0 {
|
||||
return n
|
||||
}
|
||||
delta -= int64(u)
|
||||
}
|
||||
}
|
||||
|
||||
// hash computes the rolling hash for the word stored in p. For correct
|
||||
// results its length must be equal to t.wordLen.
|
||||
func (t *hashTable) hash(p []byte) uint64 {
|
||||
var h uint64
|
||||
for _, b := range p {
|
||||
h = t.hr.RollByte(b)
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
// Matches fills the positions slice with potential matches. The
|
||||
// functions returns the number of positions filled into positions. The
|
||||
// byte slice p must have word length of the hash table.
|
||||
func (t *hashTable) Matches(p []byte, positions []int64) int {
|
||||
if len(p) != t.wordLen {
|
||||
panic(fmt.Errorf(
|
||||
"byte slice must have length %d", t.wordLen))
|
||||
}
|
||||
h := t.hash(p)
|
||||
return t.getMatches(h, positions)
|
||||
}
|
||||
|
||||
// NextOp identifies the next operation using the hash table.
|
||||
//
|
||||
// TODO: Use all repetitions to find matches.
|
||||
func (t *hashTable) NextOp(rep [4]uint32) operation {
|
||||
// get positions
|
||||
data := t.dict.data[:maxMatchLen]
|
||||
n, _ := t.dict.buf.Peek(data)
|
||||
data = data[:n]
|
||||
var p []int64
|
||||
if n < t.wordLen {
|
||||
p = t.p[:0]
|
||||
} else {
|
||||
p = t.p[:maxMatches]
|
||||
n = t.Matches(data[:t.wordLen], p)
|
||||
p = p[:n]
|
||||
}
|
||||
|
||||
// convert positions in potential distances
|
||||
head := t.dict.head
|
||||
dists := append(t.distances[:0], 1, 2, 3, 4, 5, 6, 7, 8)
|
||||
for _, pos := range p {
|
||||
dis := int(head - pos)
|
||||
if dis > shortDists {
|
||||
dists = append(dists, dis)
|
||||
}
|
||||
}
|
||||
|
||||
// check distances
|
||||
var m match
|
||||
dictLen := t.dict.DictLen()
|
||||
for _, dist := range dists {
|
||||
if dist > dictLen {
|
||||
continue
|
||||
}
|
||||
|
||||
// Here comes a trick. We are only interested in matches
|
||||
// that are longer than the matches we have been found
|
||||
// before. So before we test the whole byte sequence at
|
||||
// the given distance, we test the first byte that would
|
||||
// make the match longer. If it doesn't match the byte
|
||||
// to match, we don't to care any longer.
|
||||
i := t.dict.buf.rear - dist + m.n
|
||||
if i < 0 {
|
||||
i += len(t.dict.buf.data)
|
||||
}
|
||||
if t.dict.buf.data[i] != data[m.n] {
|
||||
// We can't get a longer match. Jump to the next
|
||||
// distance.
|
||||
continue
|
||||
}
|
||||
|
||||
n := t.dict.buf.matchLen(dist, data)
|
||||
switch n {
|
||||
case 0:
|
||||
continue
|
||||
case 1:
|
||||
if uint32(dist-minDistance) != rep[0] {
|
||||
continue
|
||||
}
|
||||
}
|
||||
if n > m.n {
|
||||
m = match{int64(dist), n}
|
||||
if n == len(data) {
|
||||
// No better match will be found.
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if m.n == 0 {
|
||||
return lit{data[0]}
|
||||
}
|
||||
return m
|
||||
}
|
||||
-170
@@ -1,170 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
// uint32LE reads an uint32 integer from a byte slice
|
||||
func uint32LE(b []byte) uint32 {
|
||||
x := uint32(b[3]) << 24
|
||||
x |= uint32(b[2]) << 16
|
||||
x |= uint32(b[1]) << 8
|
||||
x |= uint32(b[0])
|
||||
return x
|
||||
}
|
||||
|
||||
// uint64LE converts the uint64 value stored as little endian to an uint64
|
||||
// value.
|
||||
func uint64LE(b []byte) uint64 {
|
||||
x := uint64(b[7]) << 56
|
||||
x |= uint64(b[6]) << 48
|
||||
x |= uint64(b[5]) << 40
|
||||
x |= uint64(b[4]) << 32
|
||||
x |= uint64(b[3]) << 24
|
||||
x |= uint64(b[2]) << 16
|
||||
x |= uint64(b[1]) << 8
|
||||
x |= uint64(b[0])
|
||||
return x
|
||||
}
|
||||
|
||||
// putUint32LE puts an uint32 integer into a byte slice that must have at least
|
||||
// a length of 4 bytes.
|
||||
func putUint32LE(b []byte, x uint32) {
|
||||
b[0] = byte(x)
|
||||
b[1] = byte(x >> 8)
|
||||
b[2] = byte(x >> 16)
|
||||
b[3] = byte(x >> 24)
|
||||
}
|
||||
|
||||
// putUint64LE puts the uint64 value into the byte slice as little endian
|
||||
// value. The byte slice b must have at least place for 8 bytes.
|
||||
func putUint64LE(b []byte, x uint64) {
|
||||
b[0] = byte(x)
|
||||
b[1] = byte(x >> 8)
|
||||
b[2] = byte(x >> 16)
|
||||
b[3] = byte(x >> 24)
|
||||
b[4] = byte(x >> 32)
|
||||
b[5] = byte(x >> 40)
|
||||
b[6] = byte(x >> 48)
|
||||
b[7] = byte(x >> 56)
|
||||
}
|
||||
|
||||
// noHeaderSize defines the value of the length field in the LZMA header.
|
||||
const noHeaderSize uint64 = 1<<64 - 1
|
||||
|
||||
// HeaderLen provides the length of the LZMA file header.
|
||||
const HeaderLen = 13
|
||||
|
||||
// Header represents the Header of an LZMA file.
|
||||
type Header struct {
|
||||
Properties Properties
|
||||
DictSize uint32
|
||||
// uncompressed Size; negative value if no Size is given
|
||||
Size int64
|
||||
}
|
||||
|
||||
// marshalBinary marshals the header.
|
||||
func (h *Header) marshalBinary() (data []byte, err error) {
|
||||
if err = h.Properties.verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if !(h.DictSize <= MaxDictCap) {
|
||||
return nil, fmt.Errorf("lzma: DictCap %d out of range",
|
||||
h.DictSize)
|
||||
}
|
||||
|
||||
data = make([]byte, 13)
|
||||
|
||||
// property byte
|
||||
data[0] = h.Properties.Code()
|
||||
|
||||
// dictionary capacity
|
||||
putUint32LE(data[1:5], uint32(h.DictSize))
|
||||
|
||||
// uncompressed size
|
||||
var s uint64
|
||||
if h.Size > 0 {
|
||||
s = uint64(h.Size)
|
||||
} else {
|
||||
s = noHeaderSize
|
||||
}
|
||||
putUint64LE(data[5:], s)
|
||||
|
||||
return data, nil
|
||||
}
|
||||
|
||||
// unmarshalBinary unmarshals the header.
|
||||
func (h *Header) unmarshalBinary(data []byte) error {
|
||||
if len(data) != HeaderLen {
|
||||
return errors.New("lzma.unmarshalBinary: data has wrong length")
|
||||
}
|
||||
|
||||
// properties
|
||||
var err error
|
||||
if h.Properties, err = PropertiesForCode(data[0]); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// dictionary capacity
|
||||
h.DictSize = uint32LE(data[1:])
|
||||
if int(h.DictSize) < 0 {
|
||||
return errors.New(
|
||||
"LZMA header: dictionary capacity exceeds maximum " +
|
||||
"integer")
|
||||
}
|
||||
|
||||
// uncompressed size
|
||||
s := uint64LE(data[5:])
|
||||
if s == noHeaderSize {
|
||||
h.Size = -1
|
||||
} else {
|
||||
h.Size = int64(s)
|
||||
if h.Size < 0 {
|
||||
return errors.New(
|
||||
"LZMA header: uncompressed size " +
|
||||
"out of int64 range")
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// validDictSize checks whether the dictionary capacity is correct. This
|
||||
// is used to weed out wrong file headers.
|
||||
func validDictSize(dictcap int) bool {
|
||||
if int64(dictcap) == MaxDictCap {
|
||||
return true
|
||||
}
|
||||
for n := uint(10); n < 32; n++ {
|
||||
if dictcap == 1<<n {
|
||||
return true
|
||||
}
|
||||
if dictcap == 1<<n+1<<(n-1) {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// ValidHeader checks for a valid LZMA file header. It allows only
|
||||
// dictionary sizes of 2^n or 2^n+2^(n-1) with n >= 10 or 2^32-1. If
|
||||
// there is an explicit size it must not exceed 256 GiB. The length of
|
||||
// the data argument must be HeaderLen.
|
||||
//
|
||||
// This function should be disregarded because there is no guarantee that LZMA
|
||||
// files follow the constraints.
|
||||
func ValidHeader(data []byte) bool {
|
||||
var h Header
|
||||
if err := h.unmarshalBinary(data); err != nil {
|
||||
return false
|
||||
}
|
||||
if !validDictSize(int(h.DictSize)) {
|
||||
return false
|
||||
}
|
||||
return h.Size < 0 || h.Size <= 1<<38
|
||||
}
|
||||
-398
@@ -1,398 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
const (
|
||||
// maximum size of compressed data in a chunk
|
||||
maxCompressed = 1 << 16
|
||||
// maximum size of uncompressed data in a chunk
|
||||
maxUncompressed = 1 << 21
|
||||
)
|
||||
|
||||
// chunkType represents the type of an LZMA2 chunk. Note that this
|
||||
// value is an internal representation and no actual encoding of a LZMA2
|
||||
// chunk header.
|
||||
type chunkType byte
|
||||
|
||||
// Possible values for the chunk type.
|
||||
const (
|
||||
// end of stream
|
||||
cEOS chunkType = iota
|
||||
// uncompressed; reset dictionary
|
||||
cUD
|
||||
// uncompressed; no reset of dictionary
|
||||
cU
|
||||
// LZMA compressed; no reset
|
||||
cL
|
||||
// LZMA compressed; reset state
|
||||
cLR
|
||||
// LZMA compressed; reset state; new property value
|
||||
cLRN
|
||||
// LZMA compressed; reset state; new property value; reset dictionary
|
||||
cLRND
|
||||
)
|
||||
|
||||
// chunkTypeStrings provide a string representation for the chunk types.
|
||||
var chunkTypeStrings = [...]string{
|
||||
cEOS: "EOS",
|
||||
cU: "U",
|
||||
cUD: "UD",
|
||||
cL: "L",
|
||||
cLR: "LR",
|
||||
cLRN: "LRN",
|
||||
cLRND: "LRND",
|
||||
}
|
||||
|
||||
// String returns a string representation of the chunk type.
|
||||
func (c chunkType) String() string {
|
||||
if !(cEOS <= c && c <= cLRND) {
|
||||
return "unknown"
|
||||
}
|
||||
return chunkTypeStrings[c]
|
||||
}
|
||||
|
||||
// Actual encodings for the chunk types in the value. Note that the high
|
||||
// uncompressed size bits are stored in the header byte additionally.
|
||||
const (
|
||||
hEOS = 0
|
||||
hUD = 1
|
||||
hU = 2
|
||||
hL = 1 << 7
|
||||
hLR = 1<<7 | 1<<5
|
||||
hLRN = 1<<7 | 1<<6
|
||||
hLRND = 1<<7 | 1<<6 | 1<<5
|
||||
)
|
||||
|
||||
// errHeaderByte indicates an unsupported value for the chunk header
|
||||
// byte. These bytes starts the variable-length chunk header.
|
||||
var errHeaderByte = errors.New("lzma: unsupported chunk header byte")
|
||||
|
||||
// headerChunkType converts the header byte into a chunk type. It
|
||||
// ignores the uncompressed size bits in the chunk header byte.
|
||||
func headerChunkType(h byte) (c chunkType, err error) {
|
||||
if h&hL == 0 {
|
||||
// no compression
|
||||
switch h {
|
||||
case hEOS:
|
||||
c = cEOS
|
||||
case hUD:
|
||||
c = cUD
|
||||
case hU:
|
||||
c = cU
|
||||
default:
|
||||
return 0, errHeaderByte
|
||||
}
|
||||
return
|
||||
}
|
||||
switch h & hLRND {
|
||||
case hL:
|
||||
c = cL
|
||||
case hLR:
|
||||
c = cLR
|
||||
case hLRN:
|
||||
c = cLRN
|
||||
case hLRND:
|
||||
c = cLRND
|
||||
default:
|
||||
return 0, errHeaderByte
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// uncompressedHeaderLen provides the length of an uncompressed header
|
||||
const uncompressedHeaderLen = 3
|
||||
|
||||
// headerLen returns the length of the LZMA2 header for a given chunk
|
||||
// type.
|
||||
func headerLen(c chunkType) int {
|
||||
switch c {
|
||||
case cEOS:
|
||||
return 1
|
||||
case cU, cUD:
|
||||
return uncompressedHeaderLen
|
||||
case cL, cLR:
|
||||
return 5
|
||||
case cLRN, cLRND:
|
||||
return 6
|
||||
}
|
||||
panic(fmt.Errorf("unsupported chunk type %d", c))
|
||||
}
|
||||
|
||||
// chunkHeader represents the contents of a chunk header.
|
||||
type chunkHeader struct {
|
||||
ctype chunkType
|
||||
uncompressed uint32
|
||||
compressed uint16
|
||||
props Properties
|
||||
}
|
||||
|
||||
// String returns a string representation of the chunk header.
|
||||
func (h *chunkHeader) String() string {
|
||||
return fmt.Sprintf("%s %d %d %s", h.ctype, h.uncompressed,
|
||||
h.compressed, &h.props)
|
||||
}
|
||||
|
||||
// UnmarshalBinary reads the content of the chunk header from the data
|
||||
// slice. The slice must have the correct length.
|
||||
func (h *chunkHeader) UnmarshalBinary(data []byte) error {
|
||||
if len(data) == 0 {
|
||||
return errors.New("no data")
|
||||
}
|
||||
c, err := headerChunkType(data[0])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
n := headerLen(c)
|
||||
if len(data) < n {
|
||||
return errors.New("incomplete data")
|
||||
}
|
||||
if len(data) > n {
|
||||
return errors.New("invalid data length")
|
||||
}
|
||||
|
||||
*h = chunkHeader{ctype: c}
|
||||
if c == cEOS {
|
||||
return nil
|
||||
}
|
||||
|
||||
h.uncompressed = uint32(uint16BE(data[1:3]))
|
||||
if c <= cU {
|
||||
return nil
|
||||
}
|
||||
h.uncompressed |= uint32(data[0]&^hLRND) << 16
|
||||
|
||||
h.compressed = uint16BE(data[3:5])
|
||||
if c <= cLR {
|
||||
return nil
|
||||
}
|
||||
|
||||
h.props, err = PropertiesForCode(data[5])
|
||||
return err
|
||||
}
|
||||
|
||||
// MarshalBinary encodes the chunk header value. The function checks
|
||||
// whether the content of the chunk header is correct.
|
||||
func (h *chunkHeader) MarshalBinary() (data []byte, err error) {
|
||||
if h.ctype > cLRND {
|
||||
return nil, errors.New("invalid chunk type")
|
||||
}
|
||||
if err = h.props.verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
data = make([]byte, headerLen(h.ctype))
|
||||
|
||||
switch h.ctype {
|
||||
case cEOS:
|
||||
return data, nil
|
||||
case cUD:
|
||||
data[0] = hUD
|
||||
case cU:
|
||||
data[0] = hU
|
||||
case cL:
|
||||
data[0] = hL
|
||||
case cLR:
|
||||
data[0] = hLR
|
||||
case cLRN:
|
||||
data[0] = hLRN
|
||||
case cLRND:
|
||||
data[0] = hLRND
|
||||
}
|
||||
|
||||
putUint16BE(data[1:3], uint16(h.uncompressed))
|
||||
if h.ctype <= cU {
|
||||
return data, nil
|
||||
}
|
||||
data[0] |= byte(h.uncompressed>>16) &^ hLRND
|
||||
|
||||
putUint16BE(data[3:5], h.compressed)
|
||||
if h.ctype <= cLR {
|
||||
return data, nil
|
||||
}
|
||||
|
||||
data[5] = h.props.Code()
|
||||
return data, nil
|
||||
}
|
||||
|
||||
// readChunkHeader reads the chunk header from the IO reader.
|
||||
func readChunkHeader(r io.Reader) (h *chunkHeader, err error) {
|
||||
p := make([]byte, 1, 6)
|
||||
if _, err = io.ReadFull(r, p); err != nil {
|
||||
return
|
||||
}
|
||||
c, err := headerChunkType(p[0])
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
p = p[:headerLen(c)]
|
||||
if _, err = io.ReadFull(r, p[1:]); err != nil {
|
||||
return
|
||||
}
|
||||
h = new(chunkHeader)
|
||||
if err = h.UnmarshalBinary(p); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return h, nil
|
||||
}
|
||||
|
||||
// uint16BE converts a big-endian uint16 representation to an uint16
|
||||
// value.
|
||||
func uint16BE(p []byte) uint16 {
|
||||
return uint16(p[0])<<8 | uint16(p[1])
|
||||
}
|
||||
|
||||
// putUint16BE puts the big-endian uint16 presentation into the given
|
||||
// slice.
|
||||
func putUint16BE(p []byte, x uint16) {
|
||||
p[0] = byte(x >> 8)
|
||||
p[1] = byte(x)
|
||||
}
|
||||
|
||||
// chunkState is used to manage the state of the chunks
|
||||
type chunkState byte
|
||||
|
||||
// start and stop define the initial and terminating state of the chunk
|
||||
// state
|
||||
const (
|
||||
start chunkState = 'S'
|
||||
stop chunkState = 'T'
|
||||
)
|
||||
|
||||
// errors for the chunk state handling
|
||||
var (
|
||||
errChunkType = errors.New("lzma: unexpected chunk type")
|
||||
errState = errors.New("lzma: wrong chunk state")
|
||||
)
|
||||
|
||||
// next transitions state based on chunk type input
|
||||
func (c *chunkState) next(ctype chunkType) error {
|
||||
switch *c {
|
||||
// start state
|
||||
case 'S':
|
||||
switch ctype {
|
||||
case cEOS:
|
||||
*c = 'T'
|
||||
case cUD:
|
||||
*c = 'R'
|
||||
case cLRND:
|
||||
*c = 'L'
|
||||
default:
|
||||
return errChunkType
|
||||
}
|
||||
// normal LZMA mode
|
||||
case 'L':
|
||||
switch ctype {
|
||||
case cEOS:
|
||||
*c = 'T'
|
||||
case cUD:
|
||||
*c = 'R'
|
||||
case cU:
|
||||
*c = 'U'
|
||||
case cL, cLR, cLRN, cLRND:
|
||||
break
|
||||
default:
|
||||
return errChunkType
|
||||
}
|
||||
// reset required
|
||||
case 'R':
|
||||
switch ctype {
|
||||
case cEOS:
|
||||
*c = 'T'
|
||||
case cUD, cU:
|
||||
break
|
||||
case cLRN, cLRND:
|
||||
*c = 'L'
|
||||
default:
|
||||
return errChunkType
|
||||
}
|
||||
// uncompressed
|
||||
case 'U':
|
||||
switch ctype {
|
||||
case cEOS:
|
||||
*c = 'T'
|
||||
case cUD:
|
||||
*c = 'R'
|
||||
case cU:
|
||||
break
|
||||
case cL, cLR, cLRN, cLRND:
|
||||
*c = 'L'
|
||||
default:
|
||||
return errChunkType
|
||||
}
|
||||
// terminal state
|
||||
case 'T':
|
||||
return errChunkType
|
||||
default:
|
||||
return errState
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// defaultChunkType returns the default chunk type for each chunk state.
|
||||
func (c chunkState) defaultChunkType() chunkType {
|
||||
switch c {
|
||||
case 'S':
|
||||
return cLRND
|
||||
case 'L', 'U':
|
||||
return cL
|
||||
case 'R':
|
||||
return cLRN
|
||||
default:
|
||||
// no error
|
||||
return cEOS
|
||||
}
|
||||
}
|
||||
|
||||
// maxDictCap defines the maximum dictionary capacity supported by the
|
||||
// LZMA2 dictionary capacity encoding.
|
||||
const maxDictCap = 1<<32 - 1
|
||||
|
||||
// maxDictCapCode defines the maximum dictionary capacity code.
|
||||
const maxDictCapCode = 40
|
||||
|
||||
// The function decodes the dictionary capacity byte, but doesn't change
|
||||
// for the correct range of the given byte.
|
||||
func decodeDictCap(c byte) int64 {
|
||||
return (2 | int64(c)&1) << (11 + (c>>1)&0x1f)
|
||||
}
|
||||
|
||||
// DecodeDictCap decodes the encoded dictionary capacity. The function
|
||||
// returns an error if the code is out of range.
|
||||
func DecodeDictCap(c byte) (n int64, err error) {
|
||||
if c >= maxDictCapCode {
|
||||
if c == maxDictCapCode {
|
||||
return maxDictCap, nil
|
||||
}
|
||||
return 0, errors.New("lzma: invalid dictionary size code")
|
||||
}
|
||||
return decodeDictCap(c), nil
|
||||
}
|
||||
|
||||
// EncodeDictCap encodes a dictionary capacity. The function returns the
|
||||
// code for the capacity that is greater or equal n. If n exceeds the
|
||||
// maximum support dictionary capacity, the maximum value is returned.
|
||||
func EncodeDictCap(n int64) byte {
|
||||
a, b := byte(0), byte(40)
|
||||
for a < b {
|
||||
c := a + (b-a)>>1
|
||||
m := decodeDictCap(c)
|
||||
if n <= m {
|
||||
if n == m {
|
||||
return c
|
||||
}
|
||||
b = c
|
||||
} else {
|
||||
a = c + 1
|
||||
}
|
||||
}
|
||||
return a
|
||||
}
|
||||
-115
@@ -1,115 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
|
||||
// maxPosBits defines the number of bits of the position value that are used to
|
||||
// to compute the posState value. The value is used to select the tree codec
|
||||
// for length encoding and decoding.
|
||||
const maxPosBits = 4
|
||||
|
||||
// minMatchLen and maxMatchLen give the minimum and maximum values for
|
||||
// encoding and decoding length values. minMatchLen is also used as base
|
||||
// for the encoded length values.
|
||||
const (
|
||||
minMatchLen = 2
|
||||
maxMatchLen = minMatchLen + 16 + 256 - 1
|
||||
)
|
||||
|
||||
// lengthCodec support the encoding of the length value.
|
||||
type lengthCodec struct {
|
||||
choice [2]prob
|
||||
low [1 << maxPosBits]treeCodec
|
||||
mid [1 << maxPosBits]treeCodec
|
||||
high treeCodec
|
||||
}
|
||||
|
||||
// deepcopy initializes the lc value as deep copy of the source value.
|
||||
func (lc *lengthCodec) deepcopy(src *lengthCodec) {
|
||||
if lc == src {
|
||||
return
|
||||
}
|
||||
lc.choice = src.choice
|
||||
for i := range lc.low {
|
||||
lc.low[i].deepcopy(&src.low[i])
|
||||
}
|
||||
for i := range lc.mid {
|
||||
lc.mid[i].deepcopy(&src.mid[i])
|
||||
}
|
||||
lc.high.deepcopy(&src.high)
|
||||
}
|
||||
|
||||
// init initializes a new length codec.
|
||||
func (lc *lengthCodec) init() {
|
||||
for i := range lc.choice {
|
||||
lc.choice[i] = probInit
|
||||
}
|
||||
for i := range lc.low {
|
||||
lc.low[i] = makeTreeCodec(3)
|
||||
}
|
||||
for i := range lc.mid {
|
||||
lc.mid[i] = makeTreeCodec(3)
|
||||
}
|
||||
lc.high = makeTreeCodec(8)
|
||||
}
|
||||
|
||||
// Encode encodes the length offset. The length offset l can be compute by
|
||||
// subtracting minMatchLen (2) from the actual length.
|
||||
//
|
||||
// l = length - minMatchLen
|
||||
func (lc *lengthCodec) Encode(e *rangeEncoder, l uint32, posState uint32,
|
||||
) (err error) {
|
||||
if l > maxMatchLen-minMatchLen {
|
||||
return errors.New("lengthCodec.Encode: l out of range")
|
||||
}
|
||||
if l < 8 {
|
||||
if err = lc.choice[0].Encode(e, 0); err != nil {
|
||||
return
|
||||
}
|
||||
return lc.low[posState].Encode(e, l)
|
||||
}
|
||||
if err = lc.choice[0].Encode(e, 1); err != nil {
|
||||
return
|
||||
}
|
||||
if l < 16 {
|
||||
if err = lc.choice[1].Encode(e, 0); err != nil {
|
||||
return
|
||||
}
|
||||
return lc.mid[posState].Encode(e, l-8)
|
||||
}
|
||||
if err = lc.choice[1].Encode(e, 1); err != nil {
|
||||
return
|
||||
}
|
||||
if err = lc.high.Encode(e, l-16); err != nil {
|
||||
return
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decode reads the length offset. Add minMatchLen to compute the actual length
|
||||
// to the length offset l.
|
||||
func (lc *lengthCodec) Decode(d *rangeDecoder, posState uint32,
|
||||
) (l uint32, err error) {
|
||||
var b uint32
|
||||
if b, err = lc.choice[0].Decode(d); err != nil {
|
||||
return
|
||||
}
|
||||
if b == 0 {
|
||||
l, err = lc.low[posState].Decode(d)
|
||||
return
|
||||
}
|
||||
if b, err = lc.choice[1].Decode(d); err != nil {
|
||||
return
|
||||
}
|
||||
if b == 0 {
|
||||
l, err = lc.mid[posState].Decode(d)
|
||||
l += 8
|
||||
return
|
||||
}
|
||||
l, err = lc.high.Decode(d)
|
||||
l += 16
|
||||
return
|
||||
}
|
||||
-125
@@ -1,125 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// literalCodec supports the encoding of literal. It provides 768 probability
|
||||
// values per literal state. The upper 512 probabilities are used with the
|
||||
// context of a match bit.
|
||||
type literalCodec struct {
|
||||
probs []prob
|
||||
}
|
||||
|
||||
// deepcopy initializes literal codec c as a deep copy of the source.
|
||||
func (c *literalCodec) deepcopy(src *literalCodec) {
|
||||
if c == src {
|
||||
return
|
||||
}
|
||||
c.probs = make([]prob, len(src.probs))
|
||||
copy(c.probs, src.probs)
|
||||
}
|
||||
|
||||
// init initializes the literal codec.
|
||||
func (c *literalCodec) init(lc, lp int) {
|
||||
switch {
|
||||
case !(minLC <= lc && lc <= maxLC):
|
||||
panic("lc out of range")
|
||||
case !(minLP <= lp && lp <= maxLP):
|
||||
panic("lp out of range")
|
||||
}
|
||||
c.probs = make([]prob, 0x300<<uint(lc+lp))
|
||||
for i := range c.probs {
|
||||
c.probs[i] = probInit
|
||||
}
|
||||
}
|
||||
|
||||
// Encode encodes the byte s using a range encoder as well as the current LZMA
|
||||
// encoder state, a match byte and the literal state.
|
||||
func (c *literalCodec) Encode(e *rangeEncoder, s byte,
|
||||
state uint32, match byte, litState uint32,
|
||||
) (err error) {
|
||||
k := litState * 0x300
|
||||
probs := c.probs[k : k+0x300]
|
||||
symbol := uint32(1)
|
||||
r := uint32(s)
|
||||
if state >= 7 {
|
||||
m := uint32(match)
|
||||
for {
|
||||
matchBit := (m >> 7) & 1
|
||||
m <<= 1
|
||||
bit := (r >> 7) & 1
|
||||
r <<= 1
|
||||
i := ((1 + matchBit) << 8) | symbol
|
||||
if err = probs[i].Encode(e, bit); err != nil {
|
||||
return
|
||||
}
|
||||
symbol = (symbol << 1) | bit
|
||||
if matchBit != bit {
|
||||
break
|
||||
}
|
||||
if symbol >= 0x100 {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
for symbol < 0x100 {
|
||||
bit := (r >> 7) & 1
|
||||
r <<= 1
|
||||
if err = probs[symbol].Encode(e, bit); err != nil {
|
||||
return
|
||||
}
|
||||
symbol = (symbol << 1) | bit
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decode decodes a literal byte using the range decoder as well as the LZMA
|
||||
// state, a match byte, and the literal state.
|
||||
func (c *literalCodec) Decode(d *rangeDecoder,
|
||||
state uint32, match byte, litState uint32,
|
||||
) (s byte, err error) {
|
||||
k := litState * 0x300
|
||||
probs := c.probs[k : k+0x300]
|
||||
symbol := uint32(1)
|
||||
if state >= 7 {
|
||||
m := uint32(match)
|
||||
for {
|
||||
matchBit := (m >> 7) & 1
|
||||
m <<= 1
|
||||
i := ((1 + matchBit) << 8) | symbol
|
||||
bit, err := d.DecodeBit(&probs[i])
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
symbol = (symbol << 1) | bit
|
||||
if matchBit != bit {
|
||||
break
|
||||
}
|
||||
if symbol >= 0x100 {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
for symbol < 0x100 {
|
||||
bit, err := d.DecodeBit(&probs[symbol])
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
symbol = (symbol << 1) | bit
|
||||
}
|
||||
s = byte(symbol - 0x100)
|
||||
return s, nil
|
||||
}
|
||||
|
||||
// minLC and maxLC define the range for LC values.
|
||||
const (
|
||||
minLC = 0
|
||||
maxLC = 8
|
||||
)
|
||||
|
||||
// minLC and maxLC define the range for LP values.
|
||||
const (
|
||||
minLP = 0
|
||||
maxLP = 4
|
||||
)
|
||||
-52
@@ -1,52 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
|
||||
// MatchAlgorithm identifies an algorithm to find matches in the
|
||||
// dictionary.
|
||||
type MatchAlgorithm byte
|
||||
|
||||
// Supported matcher algorithms.
|
||||
const (
|
||||
HashTable4 MatchAlgorithm = iota
|
||||
BinaryTree
|
||||
)
|
||||
|
||||
// maStrings are used by the String method.
|
||||
var maStrings = map[MatchAlgorithm]string{
|
||||
HashTable4: "HashTable4",
|
||||
BinaryTree: "BinaryTree",
|
||||
}
|
||||
|
||||
// String returns a string representation of the Matcher.
|
||||
func (a MatchAlgorithm) String() string {
|
||||
if s, ok := maStrings[a]; ok {
|
||||
return s
|
||||
}
|
||||
return "unknown"
|
||||
}
|
||||
|
||||
var errUnsupportedMatchAlgorithm = errors.New(
|
||||
"lzma: unsupported match algorithm value")
|
||||
|
||||
// verify checks whether the matcher value is supported.
|
||||
func (a MatchAlgorithm) verify() error {
|
||||
if _, ok := maStrings[a]; !ok {
|
||||
return errUnsupportedMatchAlgorithm
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (a MatchAlgorithm) new(dictCap int) (m matcher, err error) {
|
||||
switch a {
|
||||
case HashTable4:
|
||||
return newHashTable(dictCap, 4)
|
||||
case BinaryTree:
|
||||
return newBinTree(dictCap)
|
||||
}
|
||||
return nil, errUnsupportedMatchAlgorithm
|
||||
}
|
||||
-55
@@ -1,55 +0,0 @@
|
||||
// Copyright 2014-2022 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 (
|
||||
"fmt"
|
||||
"unicode"
|
||||
)
|
||||
|
||||
// operation represents an operation on the dictionary during encoding or
|
||||
// decoding.
|
||||
type operation interface {
|
||||
Len() int
|
||||
}
|
||||
|
||||
// rep represents a repetition at the given distance and the given length
|
||||
type match struct {
|
||||
// supports all possible distance values, including the eos marker
|
||||
distance int64
|
||||
// length
|
||||
n int
|
||||
}
|
||||
|
||||
// Len returns the number of bytes matched.
|
||||
func (m match) Len() int {
|
||||
return m.n
|
||||
}
|
||||
|
||||
// String returns a string representation for the repetition.
|
||||
func (m match) String() string {
|
||||
return fmt.Sprintf("M{%d,%d}", m.distance, m.n)
|
||||
}
|
||||
|
||||
// lit represents a single byte literal.
|
||||
type lit struct {
|
||||
b byte
|
||||
}
|
||||
|
||||
// Len returns 1 for the single byte literal.
|
||||
func (l lit) Len() int {
|
||||
return 1
|
||||
}
|
||||
|
||||
// String returns a string representation for the literal.
|
||||
func (l lit) String() string {
|
||||
var c byte
|
||||
if unicode.IsPrint(rune(l.b)) {
|
||||
c = l.b
|
||||
} else {
|
||||
c = '.'
|
||||
}
|
||||
return fmt.Sprintf("L{%c/%02x}", c, l.b)
|
||||
}
|
||||
-53
@@ -1,53 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// movebits defines the number of bits used for the updates of probability
|
||||
// values.
|
||||
const movebits = 5
|
||||
|
||||
// probbits defines the number of bits of a probability value.
|
||||
const probbits = 11
|
||||
|
||||
// probInit defines 0.5 as initial value for prob values.
|
||||
const probInit prob = 1 << (probbits - 1)
|
||||
|
||||
// Type prob represents probabilities. The type can also be used to encode and
|
||||
// decode single bits.
|
||||
type prob uint16
|
||||
|
||||
// Dec decreases the probability. The decrease is proportional to the
|
||||
// probability value.
|
||||
func (p *prob) dec() {
|
||||
*p -= *p >> movebits
|
||||
}
|
||||
|
||||
// Inc increases the probability. The Increase is proportional to the
|
||||
// difference of 1 and the probability value.
|
||||
func (p *prob) inc() {
|
||||
*p += ((1 << probbits) - *p) >> movebits
|
||||
}
|
||||
|
||||
// Computes the new bound for a given range using the probability value.
|
||||
func (p prob) bound(r uint32) uint32 {
|
||||
return (r >> probbits) * uint32(p)
|
||||
}
|
||||
|
||||
// Bits returns 1. One is the number of bits that can be encoded or decoded
|
||||
// with a single prob value.
|
||||
func (p prob) Bits() int {
|
||||
return 1
|
||||
}
|
||||
|
||||
// Encode encodes the least-significant bit of v. Note that the p value will be
|
||||
// changed.
|
||||
func (p *prob) Encode(e *rangeEncoder, v uint32) error {
|
||||
return e.EncodeBit(v, p)
|
||||
}
|
||||
|
||||
// Decode decodes a single bit. Note that the p value will change.
|
||||
func (p *prob) Decode(d *rangeDecoder) (v uint32, err error) {
|
||||
return d.DecodeBit(p)
|
||||
}
|
||||
-69
@@ -1,69 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
)
|
||||
|
||||
// maximum and minimum values for the LZMA properties.
|
||||
const (
|
||||
minPB = 0
|
||||
maxPB = 4
|
||||
)
|
||||
|
||||
// maxPropertyCode is the possible maximum of a properties code byte.
|
||||
const maxPropertyCode = (maxPB+1)*(maxLP+1)*(maxLC+1) - 1
|
||||
|
||||
// Properties contains the parameters LC, LP and PB. The parameter LC
|
||||
// defines the number of literal context bits; parameter LP the number
|
||||
// of literal position bits and PB the number of position bits.
|
||||
type Properties struct {
|
||||
LC int
|
||||
LP int
|
||||
PB int
|
||||
}
|
||||
|
||||
// String returns the properties in a string representation.
|
||||
func (p *Properties) String() string {
|
||||
return fmt.Sprintf("LC %d LP %d PB %d", p.LC, p.LP, p.PB)
|
||||
}
|
||||
|
||||
// PropertiesForCode converts a properties code byte into a Properties value.
|
||||
func PropertiesForCode(code byte) (p Properties, err error) {
|
||||
if code > maxPropertyCode {
|
||||
return p, errors.New("lzma: invalid properties code")
|
||||
}
|
||||
p.LC = int(code % 9)
|
||||
code /= 9
|
||||
p.LP = int(code % 5)
|
||||
code /= 5
|
||||
p.PB = int(code % 5)
|
||||
return p, err
|
||||
}
|
||||
|
||||
// verify checks the properties for correctness.
|
||||
func (p *Properties) verify() error {
|
||||
if p == nil {
|
||||
return errors.New("lzma: properties are nil")
|
||||
}
|
||||
if !(minLC <= p.LC && p.LC <= maxLC) {
|
||||
return errors.New("lzma: lc out of range")
|
||||
}
|
||||
if !(minLP <= p.LP && p.LP <= maxLP) {
|
||||
return errors.New("lzma: lp out of range")
|
||||
}
|
||||
if !(minPB <= p.PB && p.PB <= maxPB) {
|
||||
return errors.New("lzma: pb out of range")
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Code converts the properties to a byte. The function assumes that
|
||||
// the properties components are all in range.
|
||||
func (p Properties) Code() byte {
|
||||
return byte((p.PB*5+p.LP)*9 + p.LC)
|
||||
}
|
||||
-222
@@ -1,222 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
"io"
|
||||
)
|
||||
|
||||
// rangeEncoder implements range encoding of single bits. The low value can
|
||||
// overflow therefore we need uint64. The cache value is used to handle
|
||||
// overflows.
|
||||
type rangeEncoder struct {
|
||||
lbw *LimitedByteWriter
|
||||
nrange uint32
|
||||
low uint64
|
||||
cacheLen int64
|
||||
cache byte
|
||||
}
|
||||
|
||||
// maxInt64 provides the maximal value of the int64 type
|
||||
const maxInt64 = 1<<63 - 1
|
||||
|
||||
// newRangeEncoder creates a new range encoder.
|
||||
func newRangeEncoder(bw io.ByteWriter) (re *rangeEncoder, err error) {
|
||||
lbw, ok := bw.(*LimitedByteWriter)
|
||||
if !ok {
|
||||
lbw = &LimitedByteWriter{BW: bw, N: maxInt64}
|
||||
}
|
||||
return &rangeEncoder{
|
||||
lbw: lbw,
|
||||
nrange: 0xffffffff,
|
||||
cacheLen: 1}, nil
|
||||
}
|
||||
|
||||
// Available returns the number of bytes that still can be written. The
|
||||
// method takes the bytes that will be currently written by Close into
|
||||
// account.
|
||||
func (e *rangeEncoder) Available() int64 {
|
||||
return e.lbw.N - (e.cacheLen + 4)
|
||||
}
|
||||
|
||||
// writeByte writes a single byte to the underlying writer. An error is
|
||||
// returned if the limit is reached. The written byte will be counted if
|
||||
// the underlying writer doesn't return an error.
|
||||
func (e *rangeEncoder) writeByte(c byte) error {
|
||||
if e.Available() < 1 {
|
||||
return ErrLimit
|
||||
}
|
||||
return e.lbw.WriteByte(c)
|
||||
}
|
||||
|
||||
// DirectEncodeBit encodes the least-significant bit of b with probability 1/2.
|
||||
func (e *rangeEncoder) DirectEncodeBit(b uint32) error {
|
||||
e.nrange >>= 1
|
||||
e.low += uint64(e.nrange) & (0 - (uint64(b) & 1))
|
||||
|
||||
// normalize
|
||||
const top = 1 << 24
|
||||
if e.nrange >= top {
|
||||
return nil
|
||||
}
|
||||
e.nrange <<= 8
|
||||
return e.shiftLow()
|
||||
}
|
||||
|
||||
// EncodeBit encodes the least significant bit of b. The p value will be
|
||||
// updated by the function depending on the bit encoded.
|
||||
func (e *rangeEncoder) EncodeBit(b uint32, p *prob) error {
|
||||
bound := p.bound(e.nrange)
|
||||
if b&1 == 0 {
|
||||
e.nrange = bound
|
||||
p.inc()
|
||||
} else {
|
||||
e.low += uint64(bound)
|
||||
e.nrange -= bound
|
||||
p.dec()
|
||||
}
|
||||
|
||||
// normalize
|
||||
const top = 1 << 24
|
||||
if e.nrange >= top {
|
||||
return nil
|
||||
}
|
||||
e.nrange <<= 8
|
||||
return e.shiftLow()
|
||||
}
|
||||
|
||||
// Close writes a complete copy of the low value.
|
||||
func (e *rangeEncoder) Close() error {
|
||||
for i := 0; i < 5; i++ {
|
||||
if err := e.shiftLow(); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// shiftLow shifts the low value for 8 bit. The shifted byte is written into
|
||||
// the byte writer. The cache value is used to handle overflows.
|
||||
func (e *rangeEncoder) shiftLow() error {
|
||||
if uint32(e.low) < 0xff000000 || (e.low>>32) != 0 {
|
||||
tmp := e.cache
|
||||
for {
|
||||
err := e.writeByte(tmp + byte(e.low>>32))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
tmp = 0xff
|
||||
e.cacheLen--
|
||||
if e.cacheLen <= 0 {
|
||||
if e.cacheLen < 0 {
|
||||
panic("negative cacheLen")
|
||||
}
|
||||
break
|
||||
}
|
||||
}
|
||||
e.cache = byte(uint32(e.low) >> 24)
|
||||
}
|
||||
e.cacheLen++
|
||||
e.low = uint64(uint32(e.low) << 8)
|
||||
return nil
|
||||
}
|
||||
|
||||
// rangeDecoder decodes single bits of the range encoding stream.
|
||||
type rangeDecoder struct {
|
||||
br io.ByteReader
|
||||
nrange uint32
|
||||
code uint32
|
||||
}
|
||||
|
||||
// newRangeDecoder initializes a range decoder. It reads five bytes from the
|
||||
// reader and therefore may return an error.
|
||||
func newRangeDecoder(br io.ByteReader) (d *rangeDecoder, err error) {
|
||||
d = &rangeDecoder{br: br, nrange: 0xffffffff}
|
||||
|
||||
b, err := d.br.ReadByte()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if b != 0 {
|
||||
return nil, errors.New("newRangeDecoder: first byte not zero")
|
||||
}
|
||||
|
||||
for i := 0; i < 4; i++ {
|
||||
if err = d.updateCode(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
if d.code >= d.nrange {
|
||||
return nil, errors.New("newRangeDecoder: d.code >= d.nrange")
|
||||
}
|
||||
|
||||
return d, nil
|
||||
}
|
||||
|
||||
// possiblyAtEnd checks whether the decoder may be at the end of the stream.
|
||||
func (d *rangeDecoder) possiblyAtEnd() bool {
|
||||
return d.code == 0
|
||||
}
|
||||
|
||||
// DirectDecodeBit decodes a bit with probability 1/2. The return value b will
|
||||
// contain the bit at the least-significant position. All other bits will be
|
||||
// zero.
|
||||
func (d *rangeDecoder) DirectDecodeBit() (b uint32, err error) {
|
||||
d.nrange >>= 1
|
||||
d.code -= d.nrange
|
||||
t := 0 - (d.code >> 31)
|
||||
d.code += d.nrange & t
|
||||
b = (t + 1) & 1
|
||||
|
||||
// d.code will stay less then d.nrange
|
||||
|
||||
// normalize
|
||||
// assume d.code < d.nrange
|
||||
const top = 1 << 24
|
||||
if d.nrange >= top {
|
||||
return b, nil
|
||||
}
|
||||
d.nrange <<= 8
|
||||
// d.code < d.nrange will be maintained
|
||||
return b, d.updateCode()
|
||||
}
|
||||
|
||||
// decodeBit decodes a single bit. The bit will be returned at the
|
||||
// least-significant position. All other bits will be zero. The probability
|
||||
// value will be updated.
|
||||
func (d *rangeDecoder) DecodeBit(p *prob) (b uint32, err error) {
|
||||
bound := p.bound(d.nrange)
|
||||
if d.code < bound {
|
||||
d.nrange = bound
|
||||
p.inc()
|
||||
b = 0
|
||||
} else {
|
||||
d.code -= bound
|
||||
d.nrange -= bound
|
||||
p.dec()
|
||||
b = 1
|
||||
}
|
||||
// normalize
|
||||
// assume d.code < d.nrange
|
||||
const top = 1 << 24
|
||||
if d.nrange >= top {
|
||||
return b, nil
|
||||
}
|
||||
d.nrange <<= 8
|
||||
// d.code < d.nrange will be maintained
|
||||
return b, d.updateCode()
|
||||
}
|
||||
|
||||
// updateCode reads a new byte into the code.
|
||||
func (d *rangeDecoder) updateCode() error {
|
||||
b, err := d.br.ReadByte()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
d.code = (d.code << 8) | uint32(b)
|
||||
return nil
|
||||
}
|
||||
-193
@@ -1,193 +0,0 @@
|
||||
// Copyright 2014-2022 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 does not rely on any external
|
||||
// library.
|
||||
package lzma
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
)
|
||||
|
||||
// ReaderConfig stores the parameters for the reader of the classic LZMA
|
||||
// format.
|
||||
type ReaderConfig struct {
|
||||
// Since v0.5.14 this parameter sets an upper limit for a .lzma file's
|
||||
// dictionary size. This helps to mitigate problems with mangled
|
||||
// headers.
|
||||
DictCap int
|
||||
}
|
||||
|
||||
// fill converts the zero values of the configuration to the default values.
|
||||
func (c *ReaderConfig) fill() {
|
||||
if c.DictCap == 0 {
|
||||
// set an upper limit of 2 GiB-1 for dictionary capacity
|
||||
// to address the zero prefix security issue.
|
||||
c.DictCap = (1 << 31) - 1
|
||||
// original: 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.
|
||||
//
|
||||
// # Security concerns
|
||||
//
|
||||
// Note that LZMA format doesn't support a magic marker in the header. So
|
||||
// [NewReader] cannot determine whether it reads the actual header. For instance
|
||||
// the LZMA stream might have a zero byte in front of the reader, leading to
|
||||
// larger dictionary sizes and file sizes. The code will detect later that there
|
||||
// are problems with the stream, but the dictionary has already been allocated
|
||||
// and this might consume a lot of memory.
|
||||
//
|
||||
// Version 0.5.14 introduces built-in mitigations:
|
||||
//
|
||||
// - The [ReaderConfig] DictCap field is now interpreted as a limit for the
|
||||
// dictionary size.
|
||||
// - The default is 2 Gigabytes minus 1 byte (2^31-1 bytes).
|
||||
// - Users can check with the [Reader.Header] method what the actual values are in
|
||||
// their LZMA files and set a smaller limit using [ReaderConfig].
|
||||
// - The dictionary size doesn't exceed the larger of the file size and
|
||||
// the minimum dictionary size. This is another measure to prevent huge
|
||||
// memory allocations for the dictionary.
|
||||
// - The code supports stream sizes only up to a pebibyte (1024^5).
|
||||
type Reader struct {
|
||||
lzma io.Reader
|
||||
header Header
|
||||
// headerOrig stores the original header read from the stream.
|
||||
headerOrig 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)
|
||||
}
|
||||
|
||||
// ErrDictSize reports about an error of the dictionary size.
|
||||
type ErrDictSize struct {
|
||||
ConfigDictCap int
|
||||
HeaderDictSize uint32
|
||||
Message string
|
||||
}
|
||||
|
||||
// Error returns the error message.
|
||||
func (e *ErrDictSize) Error() string {
|
||||
return e.Message
|
||||
}
|
||||
|
||||
func newErrDictSize(messageformat string,
|
||||
configDictCap int, headerDictSize uint32,
|
||||
args ...interface{}) *ErrDictSize {
|
||||
newArgs := make([]interface{}, len(args)+2)
|
||||
newArgs[0] = configDictCap
|
||||
newArgs[1] = headerDictSize
|
||||
copy(newArgs[2:], args)
|
||||
return &ErrDictSize{
|
||||
ConfigDictCap: configDictCap,
|
||||
HeaderDictSize: headerDictSize,
|
||||
Message: fmt.Sprintf(messageformat, newArgs...),
|
||||
}
|
||||
}
|
||||
|
||||
// We support only files not larger than 1 << 50 bytes (a pebibyte, 1024^5).
|
||||
const maxStreamSize = 1 << 50
|
||||
|
||||
// NewReader creates a new reader for an LZMA stream in the classic
|
||||
// format. The function reads and verifies 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.header.unmarshalBinary(data); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
r.headerOrig = r.header
|
||||
dictSize := int64(r.header.DictSize)
|
||||
if int64(c.DictCap) < dictSize {
|
||||
return nil, newErrDictSize(
|
||||
"lzma: header dictionary size %[2]d exceeds configured dictionary capacity %[1]d",
|
||||
c.DictCap, uint32(dictSize),
|
||||
)
|
||||
}
|
||||
if dictSize < MinDictCap {
|
||||
dictSize = MinDictCap
|
||||
}
|
||||
// original code: disabled this because there is no point in increasing
|
||||
// the dictionary above what is stated in the file.
|
||||
/*
|
||||
if int64(c.DictCap) > int64(dictSize) {
|
||||
dictSize = int64(c.DictCap)
|
||||
}
|
||||
*/
|
||||
size := r.header.Size
|
||||
if size >= 0 && size < dictSize {
|
||||
dictSize = size
|
||||
}
|
||||
// Protect against modified or malicious headers.
|
||||
if size > maxStreamSize {
|
||||
return nil, fmt.Errorf(
|
||||
"lzma: stream size %d exceeds a pebibyte (1024^5)",
|
||||
size)
|
||||
}
|
||||
if dictSize < MinDictCap {
|
||||
dictSize = MinDictCap
|
||||
}
|
||||
|
||||
r.header.DictSize = uint32(dictSize)
|
||||
|
||||
state := newState(r.header.Properties)
|
||||
dict, err := newDecoderDict(int(dictSize))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
r.d, err = newDecoder(ByteReader(lzma), state, dict, r.header.Size)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return r, nil
|
||||
}
|
||||
|
||||
// Header returns the header as read from the LZMA stream. It is intended to
|
||||
// allow the user to understand what parameters are typically provided in the
|
||||
// headers of the LZMA files and set the DictCap field in [ReaderConfig]
|
||||
// accordingly.
|
||||
func (r *Reader) Header() (h Header, ok bool) {
|
||||
return r.headerOrig, r.d != 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)
|
||||
}
|
||||
-231
@@ -1,231 +0,0 @@
|
||||
// Copyright 2014-2022 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"
|
||||
"io"
|
||||
|
||||
"github.com/ulikunitz/xz/internal/xlog"
|
||||
)
|
||||
|
||||
// Reader2Config stores the parameters for the LZMA2 reader.
|
||||
// format.
|
||||
type Reader2Config struct {
|
||||
DictCap int
|
||||
}
|
||||
|
||||
// fill converts the zero values of the configuration to the default values.
|
||||
func (c *Reader2Config) fill() {
|
||||
if c.DictCap == 0 {
|
||||
c.DictCap = 8 * 1024 * 1024
|
||||
}
|
||||
}
|
||||
|
||||
// Verify checks the reader configuration for errors. Zero configuration values
|
||||
// will be replaced by default values.
|
||||
func (c *Reader2Config) Verify() error {
|
||||
c.fill()
|
||||
if !(MinDictCap <= c.DictCap && int64(c.DictCap) <= MaxDictCap) {
|
||||
return errors.New("lzma: dictionary capacity is out of range")
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Reader2 supports the reading of LZMA2 chunk sequences. Note that the
|
||||
// first chunk should have a dictionary reset and the first compressed
|
||||
// chunk a properties reset. The chunk sequence may not be terminated by
|
||||
// an end-of-stream chunk.
|
||||
type Reader2 struct {
|
||||
r io.Reader
|
||||
err error
|
||||
|
||||
dict *decoderDict
|
||||
ur *uncompressedReader
|
||||
decoder *decoder
|
||||
chunkReader io.Reader
|
||||
|
||||
cstate chunkState
|
||||
}
|
||||
|
||||
// NewReader2 creates a reader for an LZMA2 chunk sequence.
|
||||
func NewReader2(lzma2 io.Reader) (r *Reader2, err error) {
|
||||
return Reader2Config{}.NewReader2(lzma2)
|
||||
}
|
||||
|
||||
// NewReader2 creates an LZMA2 reader using the given configuration.
|
||||
func (c Reader2Config) NewReader2(lzma2 io.Reader) (r *Reader2, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
r = &Reader2{r: lzma2, cstate: start}
|
||||
r.dict, err = newDecoderDict(c.DictCap)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err = r.startChunk(); err != nil {
|
||||
r.err = err
|
||||
}
|
||||
return r, nil
|
||||
}
|
||||
|
||||
// uncompressed tests whether the chunk type specifies an uncompressed
|
||||
// chunk.
|
||||
func uncompressed(ctype chunkType) bool {
|
||||
return ctype == cU || ctype == cUD
|
||||
}
|
||||
|
||||
// startChunk parses a new chunk.
|
||||
func (r *Reader2) startChunk() error {
|
||||
r.chunkReader = nil
|
||||
header, err := readChunkHeader(r.r)
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return err
|
||||
}
|
||||
xlog.Debugf("chunk header %v", header)
|
||||
if err = r.cstate.next(header.ctype); err != nil {
|
||||
return err
|
||||
}
|
||||
if r.cstate == stop {
|
||||
return io.EOF
|
||||
}
|
||||
if header.ctype == cUD || header.ctype == cLRND {
|
||||
r.dict.Reset()
|
||||
}
|
||||
size := int64(header.uncompressed) + 1
|
||||
if uncompressed(header.ctype) {
|
||||
if r.ur != nil {
|
||||
r.ur.Reopen(r.r, size)
|
||||
} else {
|
||||
r.ur = newUncompressedReader(r.r, r.dict, size)
|
||||
}
|
||||
r.chunkReader = r.ur
|
||||
return nil
|
||||
}
|
||||
br := ByteReader(io.LimitReader(r.r, int64(header.compressed)+1))
|
||||
if r.decoder == nil {
|
||||
state := newState(header.props)
|
||||
r.decoder, err = newDecoder(br, state, r.dict, size)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
r.chunkReader = r.decoder
|
||||
return nil
|
||||
}
|
||||
switch header.ctype {
|
||||
case cLR:
|
||||
r.decoder.State.Reset()
|
||||
case cLRN, cLRND:
|
||||
r.decoder.State = newState(header.props)
|
||||
}
|
||||
err = r.decoder.Reopen(br, size)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
r.chunkReader = r.decoder
|
||||
return nil
|
||||
}
|
||||
|
||||
// Read reads data from the LZMA2 chunk sequence.
|
||||
func (r *Reader2) Read(p []byte) (n int, err error) {
|
||||
if r.err != nil {
|
||||
return 0, r.err
|
||||
}
|
||||
for n < len(p) {
|
||||
var k int
|
||||
k, err = r.chunkReader.Read(p[n:])
|
||||
n += k
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = r.startChunk()
|
||||
if err == nil {
|
||||
continue
|
||||
}
|
||||
}
|
||||
r.err = err
|
||||
return n, err
|
||||
}
|
||||
if k == 0 {
|
||||
r.err = errors.New("lzma: Reader2 doesn't get data")
|
||||
return n, r.err
|
||||
}
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
// EOS returns whether the LZMA2 stream has been terminated by an
|
||||
// end-of-stream chunk.
|
||||
func (r *Reader2) EOS() bool {
|
||||
return r.cstate == stop
|
||||
}
|
||||
|
||||
// uncompressedReader is used to read uncompressed chunks.
|
||||
type uncompressedReader struct {
|
||||
lr io.LimitedReader
|
||||
Dict *decoderDict
|
||||
eof bool
|
||||
err error
|
||||
}
|
||||
|
||||
// newUncompressedReader initializes a new uncompressedReader.
|
||||
func newUncompressedReader(r io.Reader, dict *decoderDict, size int64) *uncompressedReader {
|
||||
ur := &uncompressedReader{
|
||||
lr: io.LimitedReader{R: r, N: size},
|
||||
Dict: dict,
|
||||
}
|
||||
return ur
|
||||
}
|
||||
|
||||
// Reopen reinitializes an uncompressed reader.
|
||||
func (ur *uncompressedReader) Reopen(r io.Reader, size int64) {
|
||||
ur.err = nil
|
||||
ur.eof = false
|
||||
ur.lr = io.LimitedReader{R: r, N: size}
|
||||
}
|
||||
|
||||
// fill reads uncompressed data into the dictionary.
|
||||
func (ur *uncompressedReader) fill() error {
|
||||
if !ur.eof {
|
||||
n, err := io.CopyN(ur.Dict, &ur.lr, int64(ur.Dict.Available()))
|
||||
if err != io.EOF {
|
||||
return err
|
||||
}
|
||||
ur.eof = true
|
||||
if n > 0 {
|
||||
return nil
|
||||
}
|
||||
}
|
||||
if ur.lr.N != 0 {
|
||||
return io.ErrUnexpectedEOF
|
||||
}
|
||||
return io.EOF
|
||||
}
|
||||
|
||||
// Read reads uncompressed data from the limited reader.
|
||||
func (ur *uncompressedReader) Read(p []byte) (n int, err error) {
|
||||
if ur.err != nil {
|
||||
return 0, ur.err
|
||||
}
|
||||
for {
|
||||
var k int
|
||||
k, err = ur.Dict.Read(p[n:])
|
||||
n += k
|
||||
if n >= len(p) {
|
||||
return n, nil
|
||||
}
|
||||
if err != nil {
|
||||
break
|
||||
}
|
||||
err = ur.fill()
|
||||
if err != nil {
|
||||
break
|
||||
}
|
||||
}
|
||||
ur.err = err
|
||||
return n, err
|
||||
}
|
||||
-145
@@ -1,145 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// states defines the overall state count
|
||||
const states = 12
|
||||
|
||||
// State maintains the full state of the operation encoding or decoding
|
||||
// process.
|
||||
type state struct {
|
||||
rep [4]uint32
|
||||
isMatch [states << maxPosBits]prob
|
||||
isRepG0Long [states << maxPosBits]prob
|
||||
isRep [states]prob
|
||||
isRepG0 [states]prob
|
||||
isRepG1 [states]prob
|
||||
isRepG2 [states]prob
|
||||
litCodec literalCodec
|
||||
lenCodec lengthCodec
|
||||
repLenCodec lengthCodec
|
||||
distCodec distCodec
|
||||
state uint32
|
||||
posBitMask uint32
|
||||
Properties Properties
|
||||
}
|
||||
|
||||
// initProbSlice initializes a slice of probabilities.
|
||||
func initProbSlice(p []prob) {
|
||||
for i := range p {
|
||||
p[i] = probInit
|
||||
}
|
||||
}
|
||||
|
||||
// Reset sets all state information to the original values.
|
||||
func (s *state) Reset() {
|
||||
p := s.Properties
|
||||
*s = state{
|
||||
Properties: p,
|
||||
// dict: s.dict,
|
||||
posBitMask: (uint32(1) << uint(p.PB)) - 1,
|
||||
}
|
||||
initProbSlice(s.isMatch[:])
|
||||
initProbSlice(s.isRep[:])
|
||||
initProbSlice(s.isRepG0[:])
|
||||
initProbSlice(s.isRepG1[:])
|
||||
initProbSlice(s.isRepG2[:])
|
||||
initProbSlice(s.isRepG0Long[:])
|
||||
s.litCodec.init(p.LC, p.LP)
|
||||
s.lenCodec.init()
|
||||
s.repLenCodec.init()
|
||||
s.distCodec.init()
|
||||
}
|
||||
|
||||
// newState creates a new state from the give Properties.
|
||||
func newState(p Properties) *state {
|
||||
s := &state{Properties: p}
|
||||
s.Reset()
|
||||
return s
|
||||
}
|
||||
|
||||
// deepcopy initializes s as a deep copy of the source.
|
||||
func (s *state) deepcopy(src *state) {
|
||||
if s == src {
|
||||
return
|
||||
}
|
||||
s.rep = src.rep
|
||||
s.isMatch = src.isMatch
|
||||
s.isRepG0Long = src.isRepG0Long
|
||||
s.isRep = src.isRep
|
||||
s.isRepG0 = src.isRepG0
|
||||
s.isRepG1 = src.isRepG1
|
||||
s.isRepG2 = src.isRepG2
|
||||
s.litCodec.deepcopy(&src.litCodec)
|
||||
s.lenCodec.deepcopy(&src.lenCodec)
|
||||
s.repLenCodec.deepcopy(&src.repLenCodec)
|
||||
s.distCodec.deepcopy(&src.distCodec)
|
||||
s.state = src.state
|
||||
s.posBitMask = src.posBitMask
|
||||
s.Properties = src.Properties
|
||||
}
|
||||
|
||||
// cloneState creates a new clone of the give state.
|
||||
func cloneState(src *state) *state {
|
||||
s := new(state)
|
||||
s.deepcopy(src)
|
||||
return s
|
||||
}
|
||||
|
||||
// updateStateLiteral updates the state for a literal.
|
||||
func (s *state) updateStateLiteral() {
|
||||
switch {
|
||||
case s.state < 4:
|
||||
s.state = 0
|
||||
return
|
||||
case s.state < 10:
|
||||
s.state -= 3
|
||||
return
|
||||
}
|
||||
s.state -= 6
|
||||
}
|
||||
|
||||
// updateStateMatch updates the state for a match.
|
||||
func (s *state) updateStateMatch() {
|
||||
if s.state < 7 {
|
||||
s.state = 7
|
||||
} else {
|
||||
s.state = 10
|
||||
}
|
||||
}
|
||||
|
||||
// updateStateRep updates the state for a repetition.
|
||||
func (s *state) updateStateRep() {
|
||||
if s.state < 7 {
|
||||
s.state = 8
|
||||
} else {
|
||||
s.state = 11
|
||||
}
|
||||
}
|
||||
|
||||
// updateStateShortRep updates the state for a short repetition.
|
||||
func (s *state) updateStateShortRep() {
|
||||
if s.state < 7 {
|
||||
s.state = 9
|
||||
} else {
|
||||
s.state = 11
|
||||
}
|
||||
}
|
||||
|
||||
// states computes the states of the operation codec.
|
||||
func (s *state) states(dictHead int64) (state1, state2, posState uint32) {
|
||||
state1 = s.state
|
||||
posState = uint32(dictHead) & s.posBitMask
|
||||
state2 = (s.state << maxPosBits) | posState
|
||||
return
|
||||
}
|
||||
|
||||
// litState computes the literal state.
|
||||
func (s *state) litState(prev byte, dictHead int64) uint32 {
|
||||
lp, lc := uint(s.Properties.LP), uint(s.Properties.LC)
|
||||
litState := ((uint32(dictHead) & ((1 << lp) - 1)) << lc) |
|
||||
(uint32(prev) >> (8 - lc))
|
||||
return litState
|
||||
}
|
||||
-133
@@ -1,133 +0,0 @@
|
||||
// Copyright 2014-2022 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
|
||||
|
||||
// treeCodec encodes or decodes values with a fixed bit size. It is using a
|
||||
// tree of probability value. The root of the tree is the most-significant bit.
|
||||
type treeCodec struct {
|
||||
probTree
|
||||
}
|
||||
|
||||
// makeTreeCodec makes a tree codec. The bits value must be inside the range
|
||||
// [1,32].
|
||||
func makeTreeCodec(bits int) treeCodec {
|
||||
return treeCodec{makeProbTree(bits)}
|
||||
}
|
||||
|
||||
// deepcopy initializes tc as a deep copy of the source.
|
||||
func (tc *treeCodec) deepcopy(src *treeCodec) {
|
||||
tc.probTree.deepcopy(&src.probTree)
|
||||
}
|
||||
|
||||
// Encode uses the range encoder to encode a fixed-bit-size value.
|
||||
func (tc *treeCodec) Encode(e *rangeEncoder, v uint32) (err error) {
|
||||
m := uint32(1)
|
||||
for i := int(tc.bits) - 1; i >= 0; i-- {
|
||||
b := (v >> uint(i)) & 1
|
||||
if err := e.EncodeBit(b, &tc.probs[m]); err != nil {
|
||||
return err
|
||||
}
|
||||
m = (m << 1) | b
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decodes uses the range decoder to decode a fixed-bit-size value. Errors may
|
||||
// be caused by the range decoder.
|
||||
func (tc *treeCodec) Decode(d *rangeDecoder) (v uint32, err error) {
|
||||
m := uint32(1)
|
||||
for j := 0; j < int(tc.bits); j++ {
|
||||
b, err := d.DecodeBit(&tc.probs[m])
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
m = (m << 1) | b
|
||||
}
|
||||
return m - (1 << uint(tc.bits)), nil
|
||||
}
|
||||
|
||||
// treeReverseCodec is another tree codec, where the least-significant bit is
|
||||
// the start of the probability tree.
|
||||
type treeReverseCodec struct {
|
||||
probTree
|
||||
}
|
||||
|
||||
// deepcopy initializes the treeReverseCodec as a deep copy of the
|
||||
// source.
|
||||
func (tc *treeReverseCodec) deepcopy(src *treeReverseCodec) {
|
||||
tc.probTree.deepcopy(&src.probTree)
|
||||
}
|
||||
|
||||
// makeTreeReverseCodec creates treeReverseCodec value. The bits argument must
|
||||
// be in the range [1,32].
|
||||
func makeTreeReverseCodec(bits int) treeReverseCodec {
|
||||
return treeReverseCodec{makeProbTree(bits)}
|
||||
}
|
||||
|
||||
// Encode uses range encoder to encode a fixed-bit-size value. The range
|
||||
// encoder may cause errors.
|
||||
func (tc *treeReverseCodec) Encode(v uint32, e *rangeEncoder) (err error) {
|
||||
m := uint32(1)
|
||||
for i := uint(0); i < uint(tc.bits); i++ {
|
||||
b := (v >> i) & 1
|
||||
if err := e.EncodeBit(b, &tc.probs[m]); err != nil {
|
||||
return err
|
||||
}
|
||||
m = (m << 1) | b
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decodes uses the range decoder to decode a fixed-bit-size value. Errors
|
||||
// returned by the range decoder will be returned.
|
||||
func (tc *treeReverseCodec) Decode(d *rangeDecoder) (v uint32, err error) {
|
||||
m := uint32(1)
|
||||
for j := uint(0); j < uint(tc.bits); j++ {
|
||||
b, err := d.DecodeBit(&tc.probs[m])
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
m = (m << 1) | b
|
||||
v |= b << j
|
||||
}
|
||||
return v, nil
|
||||
}
|
||||
|
||||
// probTree stores enough probability values to be used by the treeEncode and
|
||||
// treeDecode methods of the range coder types.
|
||||
type probTree struct {
|
||||
probs []prob
|
||||
bits byte
|
||||
}
|
||||
|
||||
// deepcopy initializes the probTree value as a deep copy of the source.
|
||||
func (t *probTree) deepcopy(src *probTree) {
|
||||
if t == src {
|
||||
return
|
||||
}
|
||||
t.probs = make([]prob, len(src.probs))
|
||||
copy(t.probs, src.probs)
|
||||
t.bits = src.bits
|
||||
}
|
||||
|
||||
// makeProbTree initializes a probTree structure.
|
||||
func makeProbTree(bits int) probTree {
|
||||
if !(1 <= bits && bits <= 32) {
|
||||
panic("bits outside of range [1,32]")
|
||||
}
|
||||
t := probTree{
|
||||
bits: byte(bits),
|
||||
probs: make([]prob, 1<<uint(bits)),
|
||||
}
|
||||
for i := range t.probs {
|
||||
t.probs[i] = probInit
|
||||
}
|
||||
return t
|
||||
}
|
||||
|
||||
// Bits provides the number of bits for the values to de- or encode.
|
||||
func (t *probTree) Bits() int {
|
||||
return int(t.bits)
|
||||
}
|
||||
-209
@@ -1,209 +0,0 @@
|
||||
// Copyright 2014-2022 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 (
|
||||
"bufio"
|
||||
"errors"
|
||||
"io"
|
||||
)
|
||||
|
||||
// MinDictCap and MaxDictCap provide the range of supported dictionary
|
||||
// capacities.
|
||||
const (
|
||||
MinDictCap = 1 << 12
|
||||
MaxDictCap = 1<<32 - 1
|
||||
)
|
||||
|
||||
// WriterConfig defines the configuration parameter for a writer.
|
||||
type WriterConfig struct {
|
||||
// Properties for the encoding. If the it is nil the value
|
||||
// {LC: 3, LP: 0, PB: 2} will be chosen.
|
||||
Properties *Properties
|
||||
// The capacity of the dictionary. If DictCap is zero, the value
|
||||
// 8 MiB will be chosen.
|
||||
DictCap int
|
||||
// Size of the lookahead buffer; value 0 indicates default size
|
||||
// 4096
|
||||
BufSize int
|
||||
// Match algorithm
|
||||
Matcher MatchAlgorithm
|
||||
// SizeInHeader indicates that the header will contain an
|
||||
// explicit size.
|
||||
SizeInHeader bool
|
||||
// Size of the data to be encoded. A positive value will imply
|
||||
// than an explicit size will be set in the header.
|
||||
Size int64
|
||||
// EOSMarker requests whether the EOSMarker needs to be written.
|
||||
// If no explicit size is been given the EOSMarker will be
|
||||
// set automatically.
|
||||
EOSMarker bool
|
||||
}
|
||||
|
||||
// fill converts zero-value fields to their explicit default values.
|
||||
func (c *WriterConfig) fill() {
|
||||
if c.Properties == nil {
|
||||
c.Properties = &Properties{LC: 3, LP: 0, PB: 2}
|
||||
}
|
||||
if c.DictCap == 0 {
|
||||
c.DictCap = 8 * 1024 * 1024
|
||||
}
|
||||
if c.BufSize == 0 {
|
||||
c.BufSize = 4096
|
||||
}
|
||||
if c.Size > 0 {
|
||||
c.SizeInHeader = true
|
||||
}
|
||||
if !c.SizeInHeader {
|
||||
c.EOSMarker = true
|
||||
}
|
||||
}
|
||||
|
||||
// Verify checks WriterConfig for errors. Verify will replace zero
|
||||
// values with default values.
|
||||
func (c *WriterConfig) Verify() error {
|
||||
c.fill()
|
||||
var err error
|
||||
if c == nil {
|
||||
return errors.New("lzma: WriterConfig is nil")
|
||||
}
|
||||
if c.Properties == nil {
|
||||
return errors.New("lzma: WriterConfig has no Properties set")
|
||||
}
|
||||
if err = c.Properties.verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
if !(MinDictCap <= c.DictCap && int64(c.DictCap) <= MaxDictCap) {
|
||||
return errors.New("lzma: dictionary capacity is out of range")
|
||||
}
|
||||
if !(maxMatchLen <= c.BufSize) {
|
||||
return errors.New("lzma: lookahead buffer size too small")
|
||||
}
|
||||
if c.SizeInHeader {
|
||||
if c.Size < 0 {
|
||||
return errors.New("lzma: negative size not supported")
|
||||
}
|
||||
} else if !c.EOSMarker {
|
||||
return errors.New("lzma: EOS marker is required")
|
||||
}
|
||||
if err = c.Matcher.verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// header returns the header structure for this configuration.
|
||||
func (c *WriterConfig) header() Header {
|
||||
h := Header{
|
||||
Properties: *c.Properties,
|
||||
DictSize: uint32(c.DictCap),
|
||||
Size: -1,
|
||||
}
|
||||
if c.SizeInHeader {
|
||||
h.Size = c.Size
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
// Writer writes an LZMA stream in the classic format.
|
||||
type Writer struct {
|
||||
h Header
|
||||
bw io.ByteWriter
|
||||
buf *bufio.Writer
|
||||
e *encoder
|
||||
}
|
||||
|
||||
// NewWriter creates a new LZMA writer for the classic format. The
|
||||
// method will write the header to the underlying stream.
|
||||
func (c WriterConfig) NewWriter(lzma io.Writer) (w *Writer, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
w = &Writer{h: c.header()}
|
||||
|
||||
var ok bool
|
||||
w.bw, ok = lzma.(io.ByteWriter)
|
||||
if !ok {
|
||||
w.buf = bufio.NewWriter(lzma)
|
||||
w.bw = w.buf
|
||||
}
|
||||
state := newState(w.h.Properties)
|
||||
m, err := c.Matcher.new(int(w.h.DictSize))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
dict, err := newEncoderDict(int(w.h.DictSize), c.BufSize, m)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
var flags encoderFlags
|
||||
if c.EOSMarker {
|
||||
flags = eosMarker
|
||||
}
|
||||
if w.e, err = newEncoder(w.bw, state, dict, flags); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if err = w.writeHeader(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return w, nil
|
||||
}
|
||||
|
||||
// NewWriter creates a new LZMA writer using the classic format. The
|
||||
// function writes the header to the underlying stream.
|
||||
func NewWriter(lzma io.Writer) (w *Writer, err error) {
|
||||
return WriterConfig{}.NewWriter(lzma)
|
||||
}
|
||||
|
||||
// writeHeader writes the LZMA header into the stream.
|
||||
func (w *Writer) writeHeader() error {
|
||||
data, err := w.h.marshalBinary()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
_, err = w.bw.(io.Writer).Write(data)
|
||||
return err
|
||||
}
|
||||
|
||||
// Write puts data into the Writer.
|
||||
func (w *Writer) Write(p []byte) (n int, err error) {
|
||||
if w.h.Size >= 0 {
|
||||
m := w.h.Size
|
||||
m -= w.e.Compressed() + int64(w.e.dict.Buffered())
|
||||
if m < 0 {
|
||||
m = 0
|
||||
}
|
||||
if m < int64(len(p)) {
|
||||
p = p[:m]
|
||||
err = ErrNoSpace
|
||||
}
|
||||
}
|
||||
var werr error
|
||||
if n, werr = w.e.Write(p); werr != nil {
|
||||
err = werr
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
|
||||
// Close closes the writer stream. It ensures that all data from the
|
||||
// buffer will be compressed and the LZMA stream will be finished.
|
||||
func (w *Writer) Close() error {
|
||||
if w.h.Size >= 0 {
|
||||
n := w.e.Compressed() + int64(w.e.dict.Buffered())
|
||||
if n != w.h.Size {
|
||||
return errSize
|
||||
}
|
||||
}
|
||||
err := w.e.Close()
|
||||
if w.buf != nil {
|
||||
ferr := w.buf.Flush()
|
||||
if err == nil {
|
||||
err = ferr
|
||||
}
|
||||
}
|
||||
return err
|
||||
}
|
||||
-305
@@ -1,305 +0,0 @@
|
||||
// Copyright 2014-2022 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 (
|
||||
"bytes"
|
||||
"errors"
|
||||
"io"
|
||||
)
|
||||
|
||||
// Writer2Config is used to create a Writer2 using parameters.
|
||||
type Writer2Config struct {
|
||||
// The properties for the encoding. If the it is nil the value
|
||||
// {LC: 3, LP: 0, PB: 2} will be chosen.
|
||||
Properties *Properties
|
||||
// The capacity of the dictionary. If DictCap is zero, the value
|
||||
// 8 MiB will be chosen.
|
||||
DictCap int
|
||||
// Size of the lookahead buffer; value 0 indicates default size
|
||||
// 4096
|
||||
BufSize int
|
||||
// Match algorithm
|
||||
Matcher MatchAlgorithm
|
||||
}
|
||||
|
||||
// fill replaces zero values with default values.
|
||||
func (c *Writer2Config) fill() {
|
||||
if c.Properties == nil {
|
||||
c.Properties = &Properties{LC: 3, LP: 0, PB: 2}
|
||||
}
|
||||
if c.DictCap == 0 {
|
||||
c.DictCap = 8 * 1024 * 1024
|
||||
}
|
||||
if c.BufSize == 0 {
|
||||
c.BufSize = 4096
|
||||
}
|
||||
}
|
||||
|
||||
// Verify checks the Writer2Config for correctness. Zero values will be
|
||||
// replaced by default values.
|
||||
func (c *Writer2Config) Verify() error {
|
||||
c.fill()
|
||||
var err error
|
||||
if c == nil {
|
||||
return errors.New("lzma: WriterConfig is nil")
|
||||
}
|
||||
if c.Properties == nil {
|
||||
return errors.New("lzma: WriterConfig has no Properties set")
|
||||
}
|
||||
if err = c.Properties.verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
if !(MinDictCap <= c.DictCap && int64(c.DictCap) <= MaxDictCap) {
|
||||
return errors.New("lzma: dictionary capacity is out of range")
|
||||
}
|
||||
if !(maxMatchLen <= c.BufSize) {
|
||||
return errors.New("lzma: lookahead buffer size too small")
|
||||
}
|
||||
if c.Properties.LC+c.Properties.LP > 4 {
|
||||
return errors.New("lzma: sum of lc and lp exceeds 4")
|
||||
}
|
||||
if err = c.Matcher.verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Writer2 supports the creation of an LZMA2 stream. But note that
|
||||
// written data is buffered, so call Flush or Close to write data to the
|
||||
// underlying writer. The Close method writes the end-of-stream marker
|
||||
// to the stream. So you may be able to concatenate the output of two
|
||||
// writers as long the output of the first writer has only been flushed
|
||||
// but not closed.
|
||||
//
|
||||
// Any change to the fields Properties, DictCap must be done before the
|
||||
// first call to Write, Flush or Close.
|
||||
type Writer2 struct {
|
||||
w io.Writer
|
||||
|
||||
start *state
|
||||
encoder *encoder
|
||||
|
||||
cstate chunkState
|
||||
ctype chunkType
|
||||
|
||||
buf bytes.Buffer
|
||||
lbw LimitedByteWriter
|
||||
}
|
||||
|
||||
// NewWriter2 creates an LZMA2 chunk sequence writer with the default
|
||||
// parameters and options.
|
||||
func NewWriter2(lzma2 io.Writer) (w *Writer2, err error) {
|
||||
return Writer2Config{}.NewWriter2(lzma2)
|
||||
}
|
||||
|
||||
// NewWriter2 creates a new LZMA2 writer using the given configuration.
|
||||
func (c Writer2Config) NewWriter2(lzma2 io.Writer) (w *Writer2, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
w = &Writer2{
|
||||
w: lzma2,
|
||||
start: newState(*c.Properties),
|
||||
cstate: start,
|
||||
ctype: start.defaultChunkType(),
|
||||
}
|
||||
w.buf.Grow(maxCompressed)
|
||||
w.lbw = LimitedByteWriter{BW: &w.buf, N: maxCompressed}
|
||||
m, err := c.Matcher.new(c.DictCap)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
d, err := newEncoderDict(c.DictCap, c.BufSize, m)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
w.encoder, err = newEncoder(&w.lbw, cloneState(w.start), d, 0)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return w, nil
|
||||
}
|
||||
|
||||
// written returns the number of bytes written to the current chunk
|
||||
func (w *Writer2) written() int {
|
||||
if w.encoder == nil {
|
||||
return 0
|
||||
}
|
||||
return int(w.encoder.Compressed()) + w.encoder.dict.Buffered()
|
||||
}
|
||||
|
||||
// errClosed indicates that the writer is closed.
|
||||
var errClosed = errors.New("lzma: writer closed")
|
||||
|
||||
// Writes data to LZMA2 stream. Note that written data will be buffered.
|
||||
// Use Flush or Close to ensure that data is written to the underlying
|
||||
// writer.
|
||||
func (w *Writer2) Write(p []byte) (n int, err error) {
|
||||
if w.cstate == stop {
|
||||
return 0, errClosed
|
||||
}
|
||||
for n < len(p) {
|
||||
m := maxUncompressed - w.written()
|
||||
if m <= 0 {
|
||||
panic("lzma: maxUncompressed reached")
|
||||
}
|
||||
var q []byte
|
||||
if n+m < len(p) {
|
||||
q = p[n : n+m]
|
||||
} else {
|
||||
q = p[n:]
|
||||
}
|
||||
k, err := w.encoder.Write(q)
|
||||
n += k
|
||||
if err != nil && err != ErrLimit {
|
||||
return n, err
|
||||
}
|
||||
if err == ErrLimit || k == m {
|
||||
if err = w.flushChunk(); err != nil {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
// writeUncompressedChunk writes an uncompressed chunk to the LZMA2
|
||||
// stream.
|
||||
func (w *Writer2) writeUncompressedChunk() error {
|
||||
u := w.encoder.Compressed()
|
||||
if u <= 0 {
|
||||
return errors.New("lzma: can't write empty uncompressed chunk")
|
||||
}
|
||||
if u > maxUncompressed {
|
||||
panic("overrun of uncompressed data limit")
|
||||
}
|
||||
switch w.ctype {
|
||||
case cLRND:
|
||||
w.ctype = cUD
|
||||
default:
|
||||
w.ctype = cU
|
||||
}
|
||||
w.encoder.state = w.start
|
||||
|
||||
header := chunkHeader{
|
||||
ctype: w.ctype,
|
||||
uncompressed: uint32(u - 1),
|
||||
}
|
||||
hdata, err := header.MarshalBinary()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if _, err = w.w.Write(hdata); err != nil {
|
||||
return err
|
||||
}
|
||||
_, err = w.encoder.dict.CopyN(w.w, int(u))
|
||||
return err
|
||||
}
|
||||
|
||||
// writeCompressedChunk writes a compressed chunk to the underlying
|
||||
// writer.
|
||||
func (w *Writer2) writeCompressedChunk() error {
|
||||
if w.ctype == cU || w.ctype == cUD {
|
||||
panic("chunk type uncompressed")
|
||||
}
|
||||
|
||||
u := w.encoder.Compressed()
|
||||
if u <= 0 {
|
||||
return errors.New("writeCompressedChunk: empty chunk")
|
||||
}
|
||||
if u > maxUncompressed {
|
||||
panic("overrun of uncompressed data limit")
|
||||
}
|
||||
c := w.buf.Len()
|
||||
if c <= 0 {
|
||||
panic("no compressed data")
|
||||
}
|
||||
if c > maxCompressed {
|
||||
panic("overrun of compressed data limit")
|
||||
}
|
||||
header := chunkHeader{
|
||||
ctype: w.ctype,
|
||||
uncompressed: uint32(u - 1),
|
||||
compressed: uint16(c - 1),
|
||||
props: w.encoder.state.Properties,
|
||||
}
|
||||
hdata, err := header.MarshalBinary()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if _, err = w.w.Write(hdata); err != nil {
|
||||
return err
|
||||
}
|
||||
_, err = io.Copy(w.w, &w.buf)
|
||||
return err
|
||||
}
|
||||
|
||||
// writes a single chunk to the underlying writer.
|
||||
func (w *Writer2) writeChunk() error {
|
||||
u := int(uncompressedHeaderLen + w.encoder.Compressed())
|
||||
c := headerLen(w.ctype) + w.buf.Len()
|
||||
if u < c {
|
||||
return w.writeUncompressedChunk()
|
||||
}
|
||||
return w.writeCompressedChunk()
|
||||
}
|
||||
|
||||
// flushChunk terminates the current chunk. The encoder will be reset
|
||||
// to support the next chunk.
|
||||
func (w *Writer2) flushChunk() error {
|
||||
if w.written() == 0 {
|
||||
return nil
|
||||
}
|
||||
var err error
|
||||
if err = w.encoder.Close(); err != nil {
|
||||
return err
|
||||
}
|
||||
if err = w.writeChunk(); err != nil {
|
||||
return err
|
||||
}
|
||||
w.buf.Reset()
|
||||
w.lbw.N = maxCompressed
|
||||
if err = w.encoder.Reopen(&w.lbw); err != nil {
|
||||
return err
|
||||
}
|
||||
if err = w.cstate.next(w.ctype); err != nil {
|
||||
return err
|
||||
}
|
||||
w.ctype = w.cstate.defaultChunkType()
|
||||
w.start = cloneState(w.encoder.state)
|
||||
return nil
|
||||
}
|
||||
|
||||
// Flush writes all buffered data out to the underlying stream. This
|
||||
// could result in multiple chunks to be created.
|
||||
func (w *Writer2) Flush() error {
|
||||
if w.cstate == stop {
|
||||
return errClosed
|
||||
}
|
||||
for w.written() > 0 {
|
||||
if err := w.flushChunk(); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Close terminates the LZMA2 stream with an EOS chunk.
|
||||
func (w *Writer2) Close() error {
|
||||
if w.cstate == stop {
|
||||
return errClosed
|
||||
}
|
||||
if err := w.Flush(); err != nil {
|
||||
return nil
|
||||
}
|
||||
// write zero byte EOS chunk
|
||||
_, err := w.w.Write([]byte{0})
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
w.cstate = stop
|
||||
return nil
|
||||
}
|
||||
-117
@@ -1,117 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
|
||||
"github.com/ulikunitz/xz/lzma"
|
||||
)
|
||||
|
||||
// LZMA filter constants.
|
||||
const (
|
||||
lzmaFilterID = 0x21
|
||||
lzmaFilterLen = 3
|
||||
)
|
||||
|
||||
// lzmaFilter declares the LZMA2 filter information stored in an xz
|
||||
// block header.
|
||||
type lzmaFilter struct {
|
||||
dictCap int64
|
||||
}
|
||||
|
||||
// String returns a representation of the LZMA filter.
|
||||
func (f lzmaFilter) String() string {
|
||||
return fmt.Sprintf("LZMA dict cap %#x", f.dictCap)
|
||||
}
|
||||
|
||||
// id returns the ID for the LZMA2 filter.
|
||||
func (f lzmaFilter) id() uint64 { return lzmaFilterID }
|
||||
|
||||
// MarshalBinary converts the lzmaFilter in its encoded representation.
|
||||
func (f lzmaFilter) MarshalBinary() (data []byte, err error) {
|
||||
c := lzma.EncodeDictCap(f.dictCap)
|
||||
return []byte{lzmaFilterID, 1, c}, nil
|
||||
}
|
||||
|
||||
// UnmarshalBinary unmarshals the given data representation of the LZMA2
|
||||
// filter.
|
||||
func (f *lzmaFilter) UnmarshalBinary(data []byte) error {
|
||||
if len(data) != lzmaFilterLen {
|
||||
return errors.New("xz: data for LZMA2 filter has wrong length")
|
||||
}
|
||||
if data[0] != lzmaFilterID {
|
||||
return errors.New("xz: wrong LZMA2 filter id")
|
||||
}
|
||||
if data[1] != 1 {
|
||||
return errors.New("xz: wrong LZMA2 filter size")
|
||||
}
|
||||
dc, err := lzma.DecodeDictCap(data[2])
|
||||
if err != nil {
|
||||
return errors.New("xz: wrong LZMA2 dictionary size property")
|
||||
}
|
||||
|
||||
f.dictCap = dc
|
||||
return nil
|
||||
}
|
||||
|
||||
// reader creates a new reader for the LZMA2 filter.
|
||||
func (f lzmaFilter) reader(r io.Reader, c *ReaderConfig) (fr io.Reader,
|
||||
err error) {
|
||||
|
||||
config := new(lzma.Reader2Config)
|
||||
if c != nil {
|
||||
config.DictCap = c.DictCap
|
||||
}
|
||||
dc := int(f.dictCap)
|
||||
if dc < 1 {
|
||||
return nil, errors.New("xz: LZMA2 filter parameter " +
|
||||
"dictionary capacity overflow")
|
||||
}
|
||||
if dc > config.DictCap {
|
||||
config.DictCap = dc
|
||||
}
|
||||
|
||||
fr, err = config.NewReader2(r)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return fr, nil
|
||||
}
|
||||
|
||||
// writeCloser creates a io.WriteCloser for the LZMA2 filter.
|
||||
func (f lzmaFilter) writeCloser(w io.WriteCloser, c *WriterConfig,
|
||||
) (fw io.WriteCloser, err error) {
|
||||
config := new(lzma.Writer2Config)
|
||||
if c != nil {
|
||||
*config = lzma.Writer2Config{
|
||||
Properties: c.Properties,
|
||||
DictCap: c.DictCap,
|
||||
BufSize: c.BufSize,
|
||||
Matcher: c.Matcher,
|
||||
}
|
||||
}
|
||||
|
||||
dc := int(f.dictCap)
|
||||
if dc < 1 {
|
||||
return nil, errors.New("xz: LZMA2 filter parameter " +
|
||||
"dictionary capacity overflow")
|
||||
}
|
||||
if dc > config.DictCap {
|
||||
config.DictCap = dc
|
||||
}
|
||||
|
||||
fw, err = config.NewWriter2(w)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return fw, nil
|
||||
}
|
||||
|
||||
// last returns true, because an LZMA2 filter must be the last filter in
|
||||
// the filter list.
|
||||
func (f lzmaFilter) last() bool { return true }
|
||||
-5
@@ -1,5 +0,0 @@
|
||||
#!/bin/sh
|
||||
|
||||
set -x
|
||||
pandoc -t html5 -f markdown -s --css=doc/md.css -o README.html README.md
|
||||
pandoc -t html5 -f markdown -s --css=doc/md.css -o TODO.html TODO.md
|
||||
-23
@@ -1,23 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import "hash"
|
||||
|
||||
type noneHash struct{}
|
||||
|
||||
func (h noneHash) Write(p []byte) (n int, err error) { return len(p), nil }
|
||||
|
||||
func (h noneHash) Sum(b []byte) []byte { return b }
|
||||
|
||||
func (h noneHash) Reset() {}
|
||||
|
||||
func (h noneHash) Size() int { return 0 }
|
||||
|
||||
func (h noneHash) BlockSize() int { return 0 }
|
||||
|
||||
func newNoneHash() hash.Hash {
|
||||
return &noneHash{}
|
||||
}
|
||||
-359
@@ -1,359 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz supports the compression and decompression of xz files. It
|
||||
// supports version 1.0.4 of the specification without the non-LZMA2
|
||||
// filters. See http://tukaani.org/xz/xz-file-format-1.0.4.txt
|
||||
package xz
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"hash"
|
||||
"io"
|
||||
|
||||
"github.com/ulikunitz/xz/internal/xlog"
|
||||
"github.com/ulikunitz/xz/lzma"
|
||||
)
|
||||
|
||||
// ReaderConfig defines the parameters for the xz reader. The
|
||||
// SingleStream parameter requests the reader to assume that the
|
||||
// underlying stream contains only a single stream.
|
||||
type ReaderConfig struct {
|
||||
DictCap int
|
||||
SingleStream bool
|
||||
}
|
||||
|
||||
// Verify checks the reader parameters for Validity. Zero values will be
|
||||
// replaced by default values.
|
||||
func (c *ReaderConfig) Verify() error {
|
||||
if c == nil {
|
||||
return errors.New("xz: reader parameters are nil")
|
||||
}
|
||||
lc := lzma.Reader2Config{DictCap: c.DictCap}
|
||||
if err := lc.Verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Reader supports the reading of one or multiple xz streams.
|
||||
type Reader struct {
|
||||
ReaderConfig
|
||||
|
||||
xz io.Reader
|
||||
sr *streamReader
|
||||
}
|
||||
|
||||
// streamReader decodes a single xz stream
|
||||
type streamReader struct {
|
||||
ReaderConfig
|
||||
|
||||
xz io.Reader
|
||||
br *blockReader
|
||||
newHash func() hash.Hash
|
||||
h header
|
||||
index []record
|
||||
}
|
||||
|
||||
// NewReader creates a new xz reader using the default parameters.
|
||||
// The function reads and checks the header of the first XZ stream. The
|
||||
// reader will process multiple streams including padding.
|
||||
func NewReader(xz io.Reader) (r *Reader, err error) {
|
||||
return ReaderConfig{}.NewReader(xz)
|
||||
}
|
||||
|
||||
// NewReader creates an xz stream reader. The created reader will be
|
||||
// able to process multiple streams and padding unless a SingleStream
|
||||
// has been set in the reader configuration c.
|
||||
func (c ReaderConfig) NewReader(xz io.Reader) (r *Reader, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
r = &Reader{
|
||||
ReaderConfig: c,
|
||||
xz: xz,
|
||||
}
|
||||
if r.sr, err = c.newStreamReader(xz); err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return nil, err
|
||||
}
|
||||
return r, nil
|
||||
}
|
||||
|
||||
var errUnexpectedData = errors.New("xz: unexpected data after stream")
|
||||
|
||||
// Read reads uncompressed data from the stream.
|
||||
func (r *Reader) Read(p []byte) (n int, err error) {
|
||||
for n < len(p) {
|
||||
if r.sr == nil {
|
||||
if r.SingleStream {
|
||||
data := make([]byte, 1)
|
||||
_, err = io.ReadFull(r.xz, data)
|
||||
if err != io.EOF {
|
||||
return n, errUnexpectedData
|
||||
}
|
||||
return n, io.EOF
|
||||
}
|
||||
for {
|
||||
r.sr, err = r.ReaderConfig.newStreamReader(r.xz)
|
||||
if err != errPadding {
|
||||
break
|
||||
}
|
||||
}
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
k, err := r.sr.Read(p[n:])
|
||||
n += k
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
r.sr = nil
|
||||
continue
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
var errPadding = errors.New("xz: padding (4 zero bytes) encountered")
|
||||
|
||||
// newStreamReader creates a new xz stream reader using the given configuration
|
||||
// parameters. NewReader reads and checks the header of the xz stream.
|
||||
func (c ReaderConfig) newStreamReader(xz io.Reader) (r *streamReader, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
data := make([]byte, HeaderLen)
|
||||
if _, err := io.ReadFull(xz, data[:4]); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if bytes.Equal(data[:4], []byte{0, 0, 0, 0}) {
|
||||
return nil, errPadding
|
||||
}
|
||||
if _, err = io.ReadFull(xz, data[4:]); err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return nil, err
|
||||
}
|
||||
r = &streamReader{
|
||||
ReaderConfig: c,
|
||||
xz: xz,
|
||||
index: make([]record, 0, 4),
|
||||
}
|
||||
if err = r.h.UnmarshalBinary(data); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
xlog.Debugf("xz header %s", r.h)
|
||||
if r.newHash, err = newHashFunc(r.h.flags); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return r, nil
|
||||
}
|
||||
|
||||
// readTail reads the index body and the xz footer.
|
||||
func (r *streamReader) readTail() error {
|
||||
index, n, err := readIndexBody(r.xz, len(r.index))
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return err
|
||||
}
|
||||
|
||||
for i, rec := range r.index {
|
||||
if rec != index[i] {
|
||||
return fmt.Errorf("xz: record %d is %v; want %v",
|
||||
i, rec, index[i])
|
||||
}
|
||||
}
|
||||
|
||||
p := make([]byte, footerLen)
|
||||
if _, err = io.ReadFull(r.xz, p); err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return err
|
||||
}
|
||||
var f footer
|
||||
if err = f.UnmarshalBinary(p); err != nil {
|
||||
return err
|
||||
}
|
||||
xlog.Debugf("xz footer %s", f)
|
||||
if f.flags != r.h.flags {
|
||||
return errors.New("xz: footer flags incorrect")
|
||||
}
|
||||
if f.indexSize != int64(n)+1 {
|
||||
return errors.New("xz: index size in footer wrong")
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Read reads actual data from the xz stream.
|
||||
func (r *streamReader) Read(p []byte) (n int, err error) {
|
||||
for n < len(p) {
|
||||
if r.br == nil {
|
||||
bh, hlen, err := readBlockHeader(r.xz)
|
||||
if err != nil {
|
||||
if err == errIndexIndicator {
|
||||
if err = r.readTail(); err != nil {
|
||||
return n, err
|
||||
}
|
||||
return n, io.EOF
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
xlog.Debugf("block %v", *bh)
|
||||
r.br, err = r.ReaderConfig.newBlockReader(r.xz, bh,
|
||||
hlen, r.newHash())
|
||||
if err != nil {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
k, err := r.br.Read(p[n:])
|
||||
n += k
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
r.index = append(r.index, r.br.record())
|
||||
r.br = nil
|
||||
} else {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
// countingReader is a reader that counts the bytes read.
|
||||
type countingReader struct {
|
||||
r io.Reader
|
||||
n int64
|
||||
}
|
||||
|
||||
// Read reads data from the wrapped reader and adds it to the n field.
|
||||
func (lr *countingReader) Read(p []byte) (n int, err error) {
|
||||
n, err = lr.r.Read(p)
|
||||
lr.n += int64(n)
|
||||
return n, err
|
||||
}
|
||||
|
||||
// blockReader supports the reading of a block.
|
||||
type blockReader struct {
|
||||
lxz countingReader
|
||||
header *blockHeader
|
||||
headerLen int
|
||||
n int64
|
||||
hash hash.Hash
|
||||
r io.Reader
|
||||
}
|
||||
|
||||
// newBlockReader creates a new block reader.
|
||||
func (c *ReaderConfig) newBlockReader(xz io.Reader, h *blockHeader,
|
||||
hlen int, hash hash.Hash) (br *blockReader, err error) {
|
||||
|
||||
br = &blockReader{
|
||||
lxz: countingReader{r: xz},
|
||||
header: h,
|
||||
headerLen: hlen,
|
||||
hash: hash,
|
||||
}
|
||||
|
||||
fr, err := c.newFilterReader(&br.lxz, h.filters)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if br.hash.Size() != 0 {
|
||||
br.r = io.TeeReader(fr, br.hash)
|
||||
} else {
|
||||
br.r = fr
|
||||
}
|
||||
|
||||
return br, nil
|
||||
}
|
||||
|
||||
// uncompressedSize returns the uncompressed size of the block.
|
||||
func (br *blockReader) uncompressedSize() int64 {
|
||||
return br.n
|
||||
}
|
||||
|
||||
// compressedSize returns the compressed size of the block.
|
||||
func (br *blockReader) compressedSize() int64 {
|
||||
return br.lxz.n
|
||||
}
|
||||
|
||||
// unpaddedSize computes the unpadded size for the block.
|
||||
func (br *blockReader) unpaddedSize() int64 {
|
||||
n := int64(br.headerLen)
|
||||
n += br.compressedSize()
|
||||
n += int64(br.hash.Size())
|
||||
return n
|
||||
}
|
||||
|
||||
// record returns the index record for the current block.
|
||||
func (br *blockReader) record() record {
|
||||
return record{br.unpaddedSize(), br.uncompressedSize()}
|
||||
}
|
||||
|
||||
// Read reads data from the block.
|
||||
func (br *blockReader) Read(p []byte) (n int, err error) {
|
||||
n, err = br.r.Read(p)
|
||||
br.n += int64(n)
|
||||
|
||||
u := br.header.uncompressedSize
|
||||
if u >= 0 && br.uncompressedSize() > u {
|
||||
return n, errors.New("xz: wrong uncompressed size for block")
|
||||
}
|
||||
c := br.header.compressedSize
|
||||
if c >= 0 && br.compressedSize() > c {
|
||||
return n, errors.New("xz: wrong compressed size for block")
|
||||
}
|
||||
if err != io.EOF {
|
||||
return n, err
|
||||
}
|
||||
if br.uncompressedSize() < u || br.compressedSize() < c {
|
||||
return n, io.ErrUnexpectedEOF
|
||||
}
|
||||
|
||||
s := br.hash.Size()
|
||||
k := padLen(br.lxz.n)
|
||||
q := make([]byte, k+s, k+2*s)
|
||||
if _, err = io.ReadFull(br.lxz.r, q); err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
if !allZeros(q[:k]) {
|
||||
return n, errors.New("xz: non-zero block padding")
|
||||
}
|
||||
checkSum := q[k:]
|
||||
computedSum := br.hash.Sum(checkSum[s:])
|
||||
if !bytes.Equal(checkSum, computedSum) {
|
||||
return n, errors.New("xz: checksum error for block")
|
||||
}
|
||||
return n, io.EOF
|
||||
}
|
||||
|
||||
func (c *ReaderConfig) newFilterReader(r io.Reader, f []filter) (fr io.Reader,
|
||||
err error) {
|
||||
|
||||
if err = verifyFilters(f); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
fr = r
|
||||
for i := len(f) - 1; i >= 0; i-- {
|
||||
fr, err = f[i].reader(fr, c)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
return fr, nil
|
||||
}
|
||||
-399
@@ -1,399 +0,0 @@
|
||||
// Copyright 2014-2022 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 xz
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"hash"
|
||||
"io"
|
||||
|
||||
"github.com/ulikunitz/xz/lzma"
|
||||
)
|
||||
|
||||
// WriterConfig describe the parameters for an xz writer.
|
||||
type WriterConfig struct {
|
||||
Properties *lzma.Properties
|
||||
DictCap int
|
||||
BufSize int
|
||||
BlockSize int64
|
||||
// checksum method: CRC32, CRC64 or SHA256 (default: CRC64)
|
||||
CheckSum byte
|
||||
// Forces NoChecksum (default: false)
|
||||
NoCheckSum bool
|
||||
// match algorithm
|
||||
Matcher lzma.MatchAlgorithm
|
||||
}
|
||||
|
||||
// fill replaces zero values with default values.
|
||||
func (c *WriterConfig) fill() {
|
||||
if c.Properties == nil {
|
||||
c.Properties = &lzma.Properties{LC: 3, LP: 0, PB: 2}
|
||||
}
|
||||
if c.DictCap == 0 {
|
||||
c.DictCap = 8 * 1024 * 1024
|
||||
}
|
||||
if c.BufSize == 0 {
|
||||
c.BufSize = 4096
|
||||
}
|
||||
if c.BlockSize == 0 {
|
||||
c.BlockSize = maxInt64
|
||||
}
|
||||
if c.CheckSum == 0 {
|
||||
c.CheckSum = CRC64
|
||||
}
|
||||
if c.NoCheckSum {
|
||||
c.CheckSum = None
|
||||
}
|
||||
}
|
||||
|
||||
// Verify checks the configuration for errors. Zero values will be
|
||||
// replaced by default values.
|
||||
func (c *WriterConfig) Verify() error {
|
||||
if c == nil {
|
||||
return errors.New("xz: writer configuration is nil")
|
||||
}
|
||||
c.fill()
|
||||
lc := lzma.Writer2Config{
|
||||
Properties: c.Properties,
|
||||
DictCap: c.DictCap,
|
||||
BufSize: c.BufSize,
|
||||
Matcher: c.Matcher,
|
||||
}
|
||||
if err := lc.Verify(); err != nil {
|
||||
return err
|
||||
}
|
||||
if c.BlockSize <= 0 {
|
||||
return errors.New("xz: block size out of range")
|
||||
}
|
||||
if err := verifyFlags(c.CheckSum); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// filters creates the filter list for the given parameters.
|
||||
func (c *WriterConfig) filters() []filter {
|
||||
return []filter{&lzmaFilter{int64(c.DictCap)}}
|
||||
}
|
||||
|
||||
// maxInt64 defines the maximum 64-bit signed integer.
|
||||
const maxInt64 = 1<<63 - 1
|
||||
|
||||
// verifyFilters checks the filter list for the length and the right
|
||||
// sequence of filters.
|
||||
func verifyFilters(f []filter) error {
|
||||
if len(f) == 0 {
|
||||
return errors.New("xz: no filters")
|
||||
}
|
||||
if len(f) > 4 {
|
||||
return errors.New("xz: more than four filters")
|
||||
}
|
||||
for _, g := range f[:len(f)-1] {
|
||||
if g.last() {
|
||||
return errors.New("xz: last filter is not last")
|
||||
}
|
||||
}
|
||||
if !f[len(f)-1].last() {
|
||||
return errors.New("xz: wrong last filter")
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// newFilterWriteCloser converts a filter list into a WriteCloser that
|
||||
// can be used by a blockWriter.
|
||||
func (c *WriterConfig) newFilterWriteCloser(w io.Writer, f []filter) (fw io.WriteCloser, err error) {
|
||||
if err = verifyFilters(f); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
fw = nopWriteCloser(w)
|
||||
for i := len(f) - 1; i >= 0; i-- {
|
||||
fw, err = f[i].writeCloser(fw, c)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
return fw, nil
|
||||
}
|
||||
|
||||
// nopWCloser implements a WriteCloser with a Close method not doing
|
||||
// anything.
|
||||
type nopWCloser struct {
|
||||
io.Writer
|
||||
}
|
||||
|
||||
// Close returns nil and doesn't do anything else.
|
||||
func (c nopWCloser) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
// nopWriteCloser converts the Writer into a WriteCloser with a Close
|
||||
// function that does nothing beside returning nil.
|
||||
func nopWriteCloser(w io.Writer) io.WriteCloser {
|
||||
return nopWCloser{w}
|
||||
}
|
||||
|
||||
// Writer compresses data written to it. It is an io.WriteCloser.
|
||||
type Writer struct {
|
||||
WriterConfig
|
||||
|
||||
xz io.Writer
|
||||
bw *blockWriter
|
||||
newHash func() hash.Hash
|
||||
h header
|
||||
index []record
|
||||
closed bool
|
||||
}
|
||||
|
||||
// newBlockWriter creates a new block writer writes the header out.
|
||||
func (w *Writer) newBlockWriter() error {
|
||||
var err error
|
||||
w.bw, err = w.WriterConfig.newBlockWriter(w.xz, w.newHash())
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if err = w.bw.writeHeader(w.xz); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// closeBlockWriter closes a block writer and records the sizes in the
|
||||
// index.
|
||||
func (w *Writer) closeBlockWriter() error {
|
||||
var err error
|
||||
if err = w.bw.Close(); err != nil {
|
||||
return err
|
||||
}
|
||||
w.index = append(w.index, w.bw.record())
|
||||
return nil
|
||||
}
|
||||
|
||||
// NewWriter creates a new xz writer using default parameters.
|
||||
func NewWriter(xz io.Writer) (w *Writer, err error) {
|
||||
return WriterConfig{}.NewWriter(xz)
|
||||
}
|
||||
|
||||
// NewWriter creates a new Writer using the given configuration parameters.
|
||||
func (c WriterConfig) NewWriter(xz io.Writer) (w *Writer, err error) {
|
||||
if err = c.Verify(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
w = &Writer{
|
||||
WriterConfig: c,
|
||||
xz: xz,
|
||||
h: header{c.CheckSum},
|
||||
index: make([]record, 0, 4),
|
||||
}
|
||||
if w.newHash, err = newHashFunc(c.CheckSum); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
data, err := w.h.MarshalBinary()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("w.h.MarshalBinary(): error %w", err)
|
||||
}
|
||||
if _, err = xz.Write(data); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err = w.newBlockWriter(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return w, nil
|
||||
|
||||
}
|
||||
|
||||
// Write compresses the uncompressed data provided.
|
||||
func (w *Writer) Write(p []byte) (n int, err error) {
|
||||
if w.closed {
|
||||
return 0, errClosed
|
||||
}
|
||||
for {
|
||||
k, err := w.bw.Write(p[n:])
|
||||
n += k
|
||||
if err != errNoSpace {
|
||||
return n, err
|
||||
}
|
||||
if err = w.closeBlockWriter(); err != nil {
|
||||
return n, err
|
||||
}
|
||||
if err = w.newBlockWriter(); err != nil {
|
||||
return n, err
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Close closes the writer and adds the footer to the Writer. Close
|
||||
// doesn't close the underlying writer.
|
||||
func (w *Writer) Close() error {
|
||||
if w.closed {
|
||||
return errClosed
|
||||
}
|
||||
w.closed = true
|
||||
var err error
|
||||
if err = w.closeBlockWriter(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
f := footer{flags: w.h.flags}
|
||||
if f.indexSize, err = writeIndex(w.xz, w.index); err != nil {
|
||||
return err
|
||||
}
|
||||
data, err := f.MarshalBinary()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if _, err = w.xz.Write(data); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// countingWriter is a writer that counts all data written to it.
|
||||
type countingWriter struct {
|
||||
w io.Writer
|
||||
n int64
|
||||
}
|
||||
|
||||
// Write writes data to the countingWriter.
|
||||
func (cw *countingWriter) Write(p []byte) (n int, err error) {
|
||||
n, err = cw.w.Write(p)
|
||||
cw.n += int64(n)
|
||||
if err == nil && cw.n < 0 {
|
||||
return n, errors.New("xz: counter overflow")
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// blockWriter is writes a single block.
|
||||
type blockWriter struct {
|
||||
cxz countingWriter
|
||||
// mw combines io.WriteCloser w and the hash.
|
||||
mw io.Writer
|
||||
w io.WriteCloser
|
||||
n int64
|
||||
blockSize int64
|
||||
closed bool
|
||||
headerLen int
|
||||
|
||||
filters []filter
|
||||
hash hash.Hash
|
||||
}
|
||||
|
||||
// newBlockWriter creates a new block writer.
|
||||
func (c *WriterConfig) newBlockWriter(xz io.Writer, hash hash.Hash) (bw *blockWriter, err error) {
|
||||
bw = &blockWriter{
|
||||
cxz: countingWriter{w: xz},
|
||||
blockSize: c.BlockSize,
|
||||
filters: c.filters(),
|
||||
hash: hash,
|
||||
}
|
||||
bw.w, err = c.newFilterWriteCloser(&bw.cxz, bw.filters)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if bw.hash.Size() != 0 {
|
||||
bw.mw = io.MultiWriter(bw.w, bw.hash)
|
||||
} else {
|
||||
bw.mw = bw.w
|
||||
}
|
||||
return bw, nil
|
||||
}
|
||||
|
||||
// writeHeader writes the header. If the function is called after Close
|
||||
// the commpressedSize and uncompressedSize fields will be filled.
|
||||
func (bw *blockWriter) writeHeader(w io.Writer) error {
|
||||
h := blockHeader{
|
||||
compressedSize: -1,
|
||||
uncompressedSize: -1,
|
||||
filters: bw.filters,
|
||||
}
|
||||
if bw.closed {
|
||||
h.compressedSize = bw.compressedSize()
|
||||
h.uncompressedSize = bw.uncompressedSize()
|
||||
}
|
||||
data, err := h.MarshalBinary()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if _, err = w.Write(data); err != nil {
|
||||
return err
|
||||
}
|
||||
bw.headerLen = len(data)
|
||||
return nil
|
||||
}
|
||||
|
||||
// compressed size returns the amount of data written to the underlying
|
||||
// stream.
|
||||
func (bw *blockWriter) compressedSize() int64 {
|
||||
return bw.cxz.n
|
||||
}
|
||||
|
||||
// uncompressedSize returns the number of data written to the
|
||||
// blockWriter
|
||||
func (bw *blockWriter) uncompressedSize() int64 {
|
||||
return bw.n
|
||||
}
|
||||
|
||||
// unpaddedSize returns the sum of the header length, the uncompressed
|
||||
// size of the block and the hash size.
|
||||
func (bw *blockWriter) unpaddedSize() int64 {
|
||||
if bw.headerLen <= 0 {
|
||||
panic("xz: block header not written")
|
||||
}
|
||||
n := int64(bw.headerLen)
|
||||
n += bw.compressedSize()
|
||||
n += int64(bw.hash.Size())
|
||||
return n
|
||||
}
|
||||
|
||||
// record returns the record for the current stream. Call Close before
|
||||
// calling this method.
|
||||
func (bw *blockWriter) record() record {
|
||||
return record{bw.unpaddedSize(), bw.uncompressedSize()}
|
||||
}
|
||||
|
||||
var errClosed = errors.New("xz: writer already closed")
|
||||
|
||||
var errNoSpace = errors.New("xz: no space")
|
||||
|
||||
// Write writes uncompressed data to the block writer.
|
||||
func (bw *blockWriter) Write(p []byte) (n int, err error) {
|
||||
if bw.closed {
|
||||
return 0, errClosed
|
||||
}
|
||||
|
||||
t := bw.blockSize - bw.n
|
||||
if int64(len(p)) > t {
|
||||
err = errNoSpace
|
||||
p = p[:t]
|
||||
}
|
||||
|
||||
var werr error
|
||||
n, werr = bw.mw.Write(p)
|
||||
bw.n += int64(n)
|
||||
if werr != nil {
|
||||
return n, werr
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
|
||||
// Close closes the writer.
|
||||
func (bw *blockWriter) Close() error {
|
||||
if bw.closed {
|
||||
return errClosed
|
||||
}
|
||||
bw.closed = true
|
||||
if err := bw.w.Close(); err != nil {
|
||||
return err
|
||||
}
|
||||
s := bw.hash.Size()
|
||||
k := padLen(bw.cxz.n)
|
||||
p := make([]byte, k+s)
|
||||
bw.hash.Sum(p[k:k])
|
||||
if _, err := bw.cxz.w.Write(p); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
Vendored
+3
-6
@@ -83,12 +83,9 @@ github.com/nats-io/nuid
|
||||
github.com/novox/mesh-host/internal/declaration
|
||||
github.com/novox/mesh-host/rootsearch
|
||||
github.com/novox/mesh-host/validate
|
||||
# github.com/ulikunitz/xz v0.5.17
|
||||
## explicit; go 1.20
|
||||
github.com/ulikunitz/xz
|
||||
github.com/ulikunitz/xz/internal/hash
|
||||
github.com/ulikunitz/xz/internal/xlog
|
||||
github.com/ulikunitz/xz/lzma
|
||||
# github.com/therootcompany/xz v1.0.1
|
||||
## explicit; go 1.15
|
||||
github.com/therootcompany/xz
|
||||
# golang.org/x/crypto v0.57.0
|
||||
## explicit; go 1.26.0
|
||||
golang.org/x/crypto/acme
|
||||
|
||||
Reference in New Issue
Block a user