Move changes from exp2 to main

This is largely a move to simplify a lot of the readers
Also further breaks out functions.
This commit is contained in:
Caleb Gardner
2022-05-10 01:12:13 -05:00
parent 0a2ced9072
commit 16ef5838c3
41 changed files with 1377 additions and 2293 deletions
-76
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@@ -1,76 +0,0 @@
package compression
import (
"bytes"
"encoding/binary"
"io"
"github.com/klauspost/compress/zlib"
)
type gzipInit struct {
CompressionLevel int32
WindowSize int16
Strategies int16
}
//Gzip is a decompressor for gzip type compression. Uses zlib for compression and decompression
type Gzip struct {
wrt *zlib.Writer
gzipInit
HasCustomWindow bool
HasStrategies bool
}
//NewGzipCompressorWithOptions creates a new gzip compressor/decompressor with options read from the given reader.
func NewGzipCompressorWithOptions(r io.Reader) (*Gzip, error) {
var gzip Gzip
err := binary.Read(r, binary.LittleEndian, &gzip.gzipInit)
if err != nil {
return nil, err
}
//TODO: proper support for window size and strategies
gzip.HasCustomWindow = gzip.WindowSize != 15
gzip.HasStrategies = gzip.Strategies != 0 && gzip.Strategies != 1
return &gzip, nil
}
//Decompress reads the entirety of the given reader and returns it uncompressed as a byte slice.
func (g *Gzip) Decompress(r io.Reader) ([]byte, error) {
rdr, err := zlib.NewReader(r)
if err != nil {
return nil, err
}
var data bytes.Buffer
_, err = io.Copy(&data, rdr)
if err != nil {
return nil, err
}
return data.Bytes(), nil
}
//Compress compresses the given data (as a byte array) and returns the compressed data.
func (g *Gzip) Compress(data []byte) ([]byte, error) {
var buf bytes.Buffer
var err error
if g.wrt == nil {
if g.CompressionLevel == 0 {
g.wrt = zlib.NewWriter(&buf)
} else {
g.wrt, err = zlib.NewWriterLevel(&buf, int(g.CompressionLevel))
if err != nil {
return nil, err
}
}
}
wrt, err := zlib.NewWriterLevel(&buf, int(g.CompressionLevel))
if err != nil {
return nil, err
}
_, err = wrt.Write(data)
if err != nil {
return nil, err
}
wrt.Close()
return buf.Bytes(), nil
}
-55
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@@ -1,55 +0,0 @@
package compression
import (
"bytes"
"encoding/binary"
"io"
"github.com/pierrec/lz4/v4"
)
//Lz4 is a Lz4 Compressor/Decompressor
type Lz4 struct {
HC bool
}
//NewLz4CompressorWithOptions creates a new lz4 compressor/decompressor with options read from the given reader.
func NewLz4CompressorWithOptions(r io.Reader) (*Lz4, error) {
var lz4 Lz4
var init struct {
Version int32
Flags int32
}
err := binary.Read(r, binary.LittleEndian, &init)
if err != nil {
return nil, err
}
lz4.HC = init.Flags == 1
return &lz4, nil
}
//Decompress decompresses all data from r and returns the uncompressed bytes
func (l *Lz4) Decompress(r io.Reader) ([]byte, error) {
rdr := lz4.NewReader(r)
var buf bytes.Buffer
_, err := io.Copy(&buf, rdr)
return buf.Bytes(), err
}
//Compress implements compression.Compress
func (l *Lz4) Compress(data []byte) ([]byte, error) {
var buf bytes.Buffer
w := lz4.NewWriter(&buf)
if l.HC {
err := w.Apply(lz4.CompressionLevelOption(lz4.Level9))
if err != nil {
return nil, err
}
}
_, err := w.Write(data)
if err != nil {
return nil, err
}
w.Close()
return buf.Bytes(), nil
}
-40
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@@ -1,40 +0,0 @@
package compression
import (
"bytes"
"io"
"github.com/ulikunitz/xz/lzma"
)
//Lzma is a lzma decompressor
type Lzma struct{}
//Decompress decompresses all the data in the given reader and returns the uncompressed bytes.
func (l *Lzma) Decompress(rdr io.Reader) ([]byte, error) {
r, err := lzma.NewReader(rdr)
if err != nil {
return nil, err
}
var buf bytes.Buffer
_, err = io.Copy(&buf, r)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
//Compress implements compression.Compress
func (l *Lzma) Compress(data []byte) ([]byte, error) {
var buf bytes.Buffer
w, err := lzma.NewWriter(&buf)
if err != nil {
return nil, err
}
_, err = w.Write(data)
if err != nil {
return nil, err
}
w.Close()
return buf.Bytes(), nil
}
-30
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@@ -1,30 +0,0 @@
package compression
import (
"encoding/binary"
"io"
lzo "github.com/rasky/go-lzo"
)
type Lzo struct {
Algorithm int32
Level int32
}
func NewLzoCompressorWithOptions(rdr io.Reader) (*Lzo, error) {
var lz Lzo
err := binary.Read(rdr, binary.LittleEndian, &lz)
if err != nil {
return nil, err
}
return &lz, nil
}
func (l Lzo) Decompress(rdr io.Reader) ([]byte, error) {
byt, err := lzo.Decompress1X(rdr, 0, 0)
if err != nil {
return nil, err
}
return byt, nil
}
-13
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@@ -1,13 +0,0 @@
package compression
import "io"
//Compressor is a squashfs decompressor interface. Allows for easy compression.
type Compressor interface {
Compress([]byte) ([]byte, error)
}
//Decompressor is a squashfs decompressor interface. Allows for easy decompression no matter the type of compression.
type Decompressor interface {
Decompress(io.Reader) ([]byte, error)
}
-60
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@@ -1,60 +0,0 @@
package compression
import (
"bytes"
"encoding/binary"
"io"
"github.com/therootcompany/xz"
wrtXz "github.com/ulikunitz/xz"
)
type Xz struct {
DictionarySize int32
Filters int32
}
//NewXzCompressorWithOptions creates a new Xz compressor/decompressor that reads the compressor options from the given reader.
func NewXzCompressorWithOptions(rdr io.Reader) (*Xz, error) {
var x Xz
err := binary.Read(rdr, binary.LittleEndian, &x)
if err != nil {
return nil, err
}
return &x, nil
}
//Decompress decompresses all the data from the rdr and returns the uncompressed bytes.
func (x *Xz) Decompress(rdr io.Reader) ([]byte, error) {
r, err := xz.NewReader(rdr, 0)
if err != nil {
return nil, err
}
var buf bytes.Buffer
_, err = io.Copy(&buf, r)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
//Compress implements compression.Compress
func (x *Xz) Compress(data []byte) ([]byte, error) {
var buf bytes.Buffer
w, err := wrtXz.NewWriter(&buf)
if err != nil {
return nil, err
}
w.DictCap = int(x.DictionarySize)
err = w.Verify()
if err != nil {
return nil, err
}
_, err = w.Write(data)
if err != nil {
return nil, err
}
w.Close()
return buf.Bytes(), nil
}
-51
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@@ -1,51 +0,0 @@
package compression
import (
"bytes"
"encoding/binary"
"io"
"github.com/klauspost/compress/zstd"
)
//Zstd is a zstd compressor/decompressor
type Zstd struct {
CompressionLevel int32
}
//NewZstdCompressorWithOptions creates a new Zstd with options read from the given reader
func NewZstdCompressorWithOptions(r io.Reader) (*Zstd, error) {
var zstd Zstd
err := binary.Read(r, binary.LittleEndian, &zstd)
if err != nil {
return nil, err
}
return &zstd, nil
}
//Decompress decompresses all data from the reader and returns the uncompressed data
func (z *Zstd) Decompress(r io.Reader) ([]byte, error) {
rdr, err := zstd.NewReader(r)
if err != nil {
return nil, err
}
defer rdr.Close()
var buf bytes.Buffer
_, err = io.Copy(&buf, rdr)
return buf.Bytes(), err
}
//Compress impelements compression.Compress
func (z *Zstd) Compress(data []byte) ([]byte, error) {
var buf bytes.Buffer
w, err := zstd.NewWriter(&buf, zstd.WithEncoderLevel(zstd.EncoderLevel(z.CompressionLevel)))
if err != nil {
return nil, err
}
_, err = w.Write(data)
if err != nil {
return nil, err
}
w.Close()
return buf.Bytes(), nil
}
+115
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@@ -0,0 +1,115 @@
package data
import (
"io"
"github.com/CalebQ42/squashfs/internal/decompress"
"github.com/CalebQ42/squashfs/internal/toreader"
)
type FullReader struct {
r io.ReaderAt
d decompress.Decompressor
fragRdr io.Reader
sizes []uint32
blockSize uint32
start uint64
}
func NewFullReader(r io.ReaderAt, start uint64, d decompress.Decompressor, blockSizes []uint32, blockSize uint32) *FullReader {
return &FullReader{
r: r,
start: start,
blockSize: blockSize,
sizes: blockSizes,
d: d,
}
}
func (r *FullReader) AddFragment(rdr io.Reader) {
r.fragRdr = rdr
}
type outDat struct {
err error
data []byte
i int
}
func (r FullReader) process(index int, offset int64, out chan outDat) {
var err error
var dat []byte
size := realSize(r.sizes[index])
rdr := io.LimitReader(toreader.NewReader(r.r, offset), int64(size))
if size == r.sizes[index] {
rdr, err = r.d.Reader(rdr)
}
if err == nil {
dat, err = io.ReadAll(rdr)
}
out <- outDat{
i: index,
err: err,
data: dat,
}
if clr, ok := rdr.(io.Closer); ok {
clr.Close()
}
}
func (r FullReader) WriteTo(w io.Writer) (n int64, err error) {
out := make(chan outDat, len(r.sizes))
offset := r.start
num := len(r.sizes)
for i := 0; i < num; i++ {
if i == num-1 && r.fragRdr != nil {
go func() {
dat, e := io.ReadAll(r.fragRdr)
out <- outDat{
i: num,
err: e,
data: dat,
}
if clr, ok := r.fragRdr.(io.Closer); ok {
clr.Close()
}
}()
continue
}
go r.process(i, int64(offset), out)
offset += uint64(realSize(r.sizes[i]))
}
cache := make(map[int]outDat)
var tmpN int
for cur := 0; cur < num; {
dat := <-out
if dat.err != nil {
err = dat.err
return
}
if dat.i != cur {
cache[dat.i] = dat
continue
}
tmpN, err = w.Write(dat.data)
n += int64(tmpN)
if err != nil {
return
}
cur++
var ok bool
for {
dat, ok = cache[cur]
if !ok {
break
}
tmpN, err = w.Write(dat.data)
n += int64(tmpN)
if err != nil {
return
}
cur++
}
}
return
}
+77
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@@ -0,0 +1,77 @@
package data
import (
"bytes"
"io"
"github.com/CalebQ42/squashfs/internal/decompress"
)
type Reader struct {
master io.Reader
cur io.Reader
fragRdr io.Reader
d decompress.Decompressor
blockSizes []uint32
blockSize uint32
}
func NewReader(r io.Reader, d decompress.Decompressor, blockSizes []uint32, blockSize uint32) (*Reader, error) {
var out Reader
out.d = d
out.master = r
out.blockSizes = blockSizes
out.blockSize = blockSize
err := out.advance()
return &out, err
}
func (r *Reader) AddFragment(rdr io.Reader) {
r.fragRdr = rdr
}
func realSize(siz uint32) uint32 {
return siz &^ (1 << 24)
}
func (r *Reader) advance() (err error) {
if clr, ok := r.cur.(io.Closer); ok {
clr.Close()
}
if len(r.blockSizes) == 0 {
return io.EOF
}
if len(r.blockSizes) == 1 && r.fragRdr != nil {
r.cur = r.fragRdr
} else {
size := realSize(r.blockSizes[0])
if size == 0 {
r.cur = bytes.NewReader(make([]byte, r.blockSize))
} else {
r.cur = io.LimitReader(r.master, int64(size))
if size == r.blockSizes[0] {
r.cur, err = r.d.Reader(r.cur)
}
}
}
r.blockSizes = r.blockSizes[1:]
return
}
func (r *Reader) Read(p []byte) (n int, err error) {
n, err = r.cur.Read(p)
if err == io.EOF {
err = r.advance()
if err != nil {
return
}
var tmpN int
tmp := make([]byte, len(p)-n)
tmpN, err = r.Read(tmp)
for i := range tmp {
p[n+i] = tmp[i]
}
n += tmpN
}
return
}
+13
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@@ -0,0 +1,13 @@
package decompress
import (
"io"
"github.com/klauspost/compress/zlib"
)
type GZip struct{}
func (g GZip) Reader(src io.Reader) (io.ReadCloser, error) {
return zlib.NewReader(src)
}
+7
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@@ -0,0 +1,7 @@
package decompress
import "io"
type Decompressor interface {
Reader(src io.Reader) (io.ReadCloser, error)
}
+13
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@@ -0,0 +1,13 @@
package decompress
import (
"io"
"github.com/pierrec/lz4/v4"
)
type Lz4 struct{}
func (l Lz4) Reader(r io.Reader) (io.ReadCloser, error) {
return io.NopCloser(lz4.NewReader(r)), nil
}
+14
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@@ -0,0 +1,14 @@
package decompress
import (
"io"
"github.com/ulikunitz/xz/lzma"
)
type Lzma struct{}
func (l Lzma) Reader(r io.Reader) (io.ReadCloser, error) {
rdr, err := lzma.NewReader(r)
return io.NopCloser(rdr), err
}
+18
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@@ -0,0 +1,18 @@
package decompress
import (
"bytes"
"io"
"github.com/rasky/go-lzo"
)
type Lzo struct{}
func (l Lzo) Reader(r io.Reader) (io.ReadCloser, error) {
cache, err := lzo.Decompress1X(r, 0, 0)
if err != nil {
return nil, err
}
return io.NopCloser(bytes.NewReader(cache)), nil
}
+14
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@@ -0,0 +1,14 @@
package decompress
import (
"io"
"github.com/therootcompany/xz"
)
type Xz struct{}
func (x Xz) Reader(r io.Reader) (io.ReadCloser, error) {
rdr, err := xz.NewReader(r, 0)
return io.NopCloser(rdr), err
}
+14
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@@ -0,0 +1,14 @@
package decompress
import (
"io"
"github.com/klauspost/compress/zstd"
)
type Zstd struct{}
func (z Zstd) Reader(src io.Reader) (io.ReadCloser, error) {
r, err := zstd.NewReader(src)
return r.IOReadCloser(), err
}
+59 -68
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@@ -6,82 +6,73 @@ import (
"io"
)
//Header is the header for a directory in the directory table
type Header struct {
Count uint32
InodeOffset uint32
InodeNumber uint32
type header struct {
Entries uint32
InodeStart uint32
Num uint32
}
//EntryRaw is the values that can be easily decoded
type EntryRaw struct {
Offset uint16
InodeOffset int16
Type uint16
NameSize uint16
type entryInit struct {
Offset uint16
NumOffset int16
Type uint16
NameSize uint16
}
type entry struct {
entryInit
Name []byte
}
//Entry is an entry in a directory.
type Entry struct {
Name string
InodeOffset uint32
InodeBlockOffset uint16
Type uint16
Name string
BlockStart uint32
Type uint16
Offset uint16
}
//NewEntry creates a new directory entry
func NewEntry(rdr io.Reader) (*Entry, error) {
var raw EntryRaw
err := binary.Read(rdr, binary.LittleEndian, &raw)
func readEntry(r io.Reader) (e entry, err error) {
err = binary.Read(r, binary.LittleEndian, &e.entryInit)
if err != nil {
return nil, err
}
tmp := make([]byte, raw.NameSize+1)
err = binary.Read(rdr, binary.LittleEndian, &tmp)
if err != nil {
return nil, err
}
return &Entry{
InodeBlockOffset: raw.Offset,
Type: raw.Type,
Name: string(tmp),
}, nil
}
//NewDirectory reads the directory from rdr
func NewDirectory(base io.Reader, size uint32) (entries []*Entry, err error) {
tmp := make([]byte, size)
base.Read(tmp)
rdr := bytes.NewBuffer(tmp)
for {
var hdr Header
err = binary.Read(rdr, binary.LittleEndian, &hdr)
if err == io.ErrUnexpectedEOF {
err = nil
break
} else if err != nil {
return nil, err
}
hdr.Count++
headers := hdr.Count / 256
if hdr.Count%256 > 0 {
headers++
}
for i := uint32(0); i < hdr.Count; i++ {
if i != 0 && i%256 == 0 {
err = binary.Read(rdr, binary.LittleEndian, &hdr)
if err != nil {
return nil, err
}
}
var ent *Entry
ent, err = NewEntry(rdr)
if err != nil {
return nil, err
}
ent.InodeOffset = hdr.InodeOffset
entries = append(entries, ent)
}
return
}
e.Name = make([]byte, e.NameSize+1)
err = binary.Read(r, binary.LittleEndian, &e.Name)
return
}
func ReadEntries(rdr io.Reader, size uint32) (e []Entry, err error) {
dat := make([]byte, size)
rdr.Read(dat)
r := bytes.NewReader(dat)
var h header
var en entry
for {
err = binary.Read(r, binary.LittleEndian, &h)
if err == io.ErrUnexpectedEOF {
err = nil
return
} else if err != nil {
return
}
h.Entries++
for i := 0; i < int(h.Entries); i++ {
if i != 0 && i%256 == 0 {
err = binary.Read(r, binary.LittleEndian, &h)
if err != nil {
return
}
}
en, err = readEntry(r)
if err != nil {
return
}
e = append(e, Entry{
Name: string(en.Name),
BlockStart: h.InodeStart,
Type: en.Type,
Offset: en.Offset,
})
}
}
}
+65
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@@ -0,0 +1,65 @@
package inode
import (
"encoding/binary"
"io"
)
type Directory struct {
BlockStart uint32
LinkCount uint32
Size uint16
Offset uint16
ParentNum uint32
}
type eDirectoryInit struct {
LinkCount uint32
Size uint32
BlockStart uint32
ParentNum uint32
IndCount uint16
Offset uint16
XattrInd uint32
}
type EDirectory struct {
eDirectoryInit
Indexes []DirectoryIndex
}
type directoryIndexInit struct {
Ind uint32
Start uint32
NameSize uint32
}
type DirectoryIndex struct {
directoryIndexInit
Name []byte
}
func ReadDir(r io.Reader) (d Directory, err error) {
err = binary.Read(r, binary.LittleEndian, &d)
return
}
func ReadEDir(r io.Reader) (d EDirectory, err error) {
err = binary.Read(r, binary.LittleEndian, &d.eDirectoryInit)
if err != nil {
return
}
d.Indexes = make([]DirectoryIndex, d.IndCount)
for i := range d.Indexes {
err = binary.Read(r, binary.LittleEndian, &d.Indexes[i].directoryIndexInit)
if err != nil {
return
}
d.Indexes[i].Name = make([]byte, d.Indexes[i].NameSize+1)
err = binary.Read(r, binary.LittleEndian, &d.Indexes[i].Name)
if err != nil {
return
}
}
return
}
+54
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@@ -0,0 +1,54 @@
package inode
import (
"encoding/binary"
"io"
"math"
)
type fileInit struct {
BlockStart uint32
FragInd uint32
Offset uint32
Size uint32
}
type File struct {
fileInit
BlockSizes []uint32
}
type eFileInit struct {
BlockStart uint32
Size uint64
Sparse uint64
LinkCount uint32
FragInd uint32
Offset uint32
XattrInd uint32
}
type EFile struct {
eFileInit
BlockSizes []uint32
}
func ReadFile(r io.Reader, blockSize uint32) (f File, err error) {
err = binary.Read(r, binary.LittleEndian, &f.fileInit)
if err != nil {
return
}
f.BlockSizes = make([]uint32, int(math.Ceil(float64(f.Size)/float64(blockSize))))
err = binary.Read(r, binary.LittleEndian, &f.BlockSizes)
return
}
func ReadEFile(r io.Reader, blockSize uint32) (f EFile, err error) {
err = binary.Read(r, binary.LittleEndian, &f.eFileInit)
if err != nil {
return
}
f.BlockSizes = make([]uint32, int(math.Ceil(float64(f.Size)/float64(blockSize))))
err = binary.Read(r, binary.LittleEndian, &f.BlockSizes)
return
}
+78
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@@ -0,0 +1,78 @@
package inode
import (
"encoding/binary"
"errors"
"io"
)
const (
Dir = uint16(iota + 1)
Fil
Sym
Block
Char
Fifo
Sock
EDir
EFil
ESym
EBlock
EChar
EFifo
ESock
)
type Header struct {
Type uint16
Perm uint16
UidInd uint16
GidInd uint16
ModTime uint32
Num uint32
}
type Inode struct {
Header
Data any
}
func Read(r io.Reader, blockSize uint32) (i Inode, err error) {
err = binary.Read(r, binary.LittleEndian, &i.Header)
if err != nil {
return
}
switch i.Type {
case Dir:
i.Data, err = ReadDir(r)
case Fil:
i.Data, err = ReadFile(r, blockSize)
case Sym:
i.Data, err = ReadSym(r)
case Block:
fallthrough
case Char:
i.Data, err = ReadDevice(r)
case Fifo:
fallthrough
case Sock:
i.Data, err = ReadIPC(r)
case EDir:
i.Data, err = ReadEDir(r)
case EFil:
i.Data, err = ReadEFile(r, blockSize)
case ESym:
i.Data, err = ReadESym(r)
case EBlock:
fallthrough
case EChar:
i.Data, err = ReadEDevice(r)
case EFifo:
fallthrough
case ESock:
i.Data, err = ReadEIPC(r)
default:
return i, errors.New("invalid inode type")
}
return
}
-257
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@@ -1,257 +0,0 @@
package inode
import (
"encoding/binary"
"io"
)
//The different types of inodes as defined by inodetype
const (
DirType = iota + 1
FileType
SymType
BlockDevType
CharDevType
FifoType
SocketType
ExtDirType
ExtFileType
ExtSymType
ExtBlockDeviceType
ExtCharDeviceType
ExtFifoType
ExtSocketType
)
//Header is the common header for all inodes
type Header struct {
Type uint16
Permissions uint16
UID uint16
GID uint16
ModifiedTime uint32
Number uint32
}
//Dir is self explainatory
type Dir struct {
DirectoryIndex uint32
HardLinks uint32
DirectorySize uint16
DirectoryOffset uint16
ParentInodeNumber uint32
}
//ExtDirInit is the information that can be directoy decoded
type ExtDirInit struct {
HardLinks uint32
DirectorySize uint32
DirectoryIndex uint32
ParentInodeNumber uint32
IndexCount uint16 //one less then directory indexes following structure
DirectoryOffset uint16
XattrIndex uint32
}
//ExtDir is a directory with extra info
type ExtDir struct {
Indexes []DirIndex
ExtDirInit
}
//NewExtendedDirectory creates a new ExtendedDirectory
func NewExtendedDirectory(rdr io.Reader) (ExtDir, error) {
var inode ExtDir
err := binary.Read(rdr, binary.LittleEndian, &inode.ExtDirInit)
if err != nil {
return inode, err
}
for i := uint16(0); i < inode.IndexCount; i++ {
var tmp DirIndex
tmp, err = NewDirectoryIndex(rdr)
if err != nil {
return inode, err
}
inode.Indexes = append(inode.Indexes, tmp)
}
return inode, err
}
//DirIndexInit holds the values that can be easily decoded
type DirIndexInit struct {
Offset uint32
DirTableOffset uint32
NameSize uint32
}
//DirIndex is a quick lookup provided by an ExtendedDirectory
type DirIndex struct {
Name string
DirIndexInit
}
//NewDirectoryIndex return a new DirectoryIndex
func NewDirectoryIndex(rdr io.Reader) (DirIndex, error) {
var index DirIndex
err := binary.Read(rdr, binary.LittleEndian, &index.DirIndexInit)
if err != nil {
return index, err
}
tmp := make([]byte, index.NameSize+1, index.NameSize+1)
err = binary.Read(rdr, binary.LittleEndian, &tmp)
if err != nil {
return index, err
}
index.Name = string(tmp)
return index, nil
}
//FileInit is the information that can be directly decoded
type FileInit struct {
BlockStart uint32
FragmentIndex uint32
FragmentOffset uint32
Size uint32
}
//File is self explainatory
type File struct {
BlockSizes []uint32
Fragmented bool
FileInit
}
//NewFile creates a new File
func NewFile(rdr io.Reader, blockSize uint32) (File, error) {
var inode File
err := binary.Read(rdr, binary.LittleEndian, &inode.FileInit)
if err != nil {
return inode, err
}
inode.Fragmented = inode.FragmentIndex != 0xFFFFFFFF
blocks := inode.Size / blockSize
if inode.Size%blockSize > 0 {
blocks++
}
inode.BlockSizes = make([]uint32, blocks, blocks)
err = binary.Read(rdr, binary.LittleEndian, &inode.BlockSizes)
return inode, err
}
//ExtFileInit is the information that can be directly decoded
type ExtFileInit struct {
BlockStart uint64
Size uint64
Sparse uint64
HardLinks uint32
FragmentIndex uint32
FragmentOffset uint32
XattrIndex uint32
}
//ExtFile is a file with more information
type ExtFile struct {
BlockSizes []uint32
Fragmented bool
ExtFileInit
}
//NewExtendedFile creates a new ExtendedFile
func NewExtendedFile(rdr io.Reader, blockSize uint32) (ExtFile, error) {
var inode ExtFile
err := binary.Read(rdr, binary.LittleEndian, &inode.ExtFileInit)
if err != nil {
return inode, err
}
inode.Fragmented = inode.FragmentIndex != 0xFFFFFFFF
blocks := inode.Size / uint64(blockSize)
if inode.Size%uint64(blockSize) > 0 {
blocks++
}
inode.BlockSizes = make([]uint32, blocks, blocks)
err = binary.Read(rdr, binary.LittleEndian, &inode.BlockSizes)
return inode, err
}
//SymInit is all the values that can be directly decoded
type SymInit struct {
HardLinks uint32
TargetPathSize uint32
}
//Sym is a symlink
type Sym struct {
Path string
targetPath []byte //len is TargetPathSize
SymInit
}
//NewSymlink creates a new Symlink
func NewSymlink(rdr io.Reader) (Sym, error) {
var inode Sym
err := binary.Read(rdr, binary.LittleEndian, &inode.SymInit)
if err != nil {
return inode, err
}
inode.targetPath = make([]byte, inode.TargetPathSize, inode.TargetPathSize)
err = binary.Read(rdr, binary.LittleEndian, &inode.targetPath)
if err != nil {
return inode, err
}
inode.Path = string(inode.targetPath)
return inode, err
}
//ExtSymInit is all the values that can be directly decoded
type ExtSymInit struct {
HardLinks uint32
TargetPathSize uint32
}
//ExtSym is a symlink with extra information
type ExtSym struct {
Path string
targetPath []uint8
ExtSymInit
XattrIndex uint32
}
//NewExtendedSymlink creates a new ExtendedSymlink
func NewExtendedSymlink(rdr io.Reader) (ExtSym, error) {
var inode ExtSym
err := binary.Read(rdr, binary.LittleEndian, &inode.ExtSymInit)
if err != nil {
return inode, err
}
inode.targetPath = make([]uint8, inode.TargetPathSize, inode.TargetPathSize)
err = binary.Read(rdr, binary.LittleEndian, &inode.targetPath)
if err != nil {
return inode, err
}
inode.Path = string(inode.targetPath)
err = binary.Read(rdr, binary.LittleEndian, &inode.XattrIndex)
return inode, err
}
//Device is a device
type Device struct {
HardLinks uint32
Device uint32
}
//ExtDevice is a device with more info
type ExtDevice struct {
Device
XattrIndex uint32
}
//IPC is a Fifo or Socket device
type IPC struct {
HardLink uint32
}
//ExtIPC is a IPC device with extra info
type ExtIPC struct {
IPC
XattrIndex uint32
}
+45
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@@ -0,0 +1,45 @@
package inode
import (
"encoding/binary"
"io"
)
type Device struct {
LinkCount uint32
Dev uint32
}
type EDevice struct {
Device
XattrInd uint32
}
func ReadDevice(r io.Reader) (d Device, err error) {
err = binary.Read(r, binary.LittleEndian, &d)
return
}
func ReadEDevice(r io.Reader) (d EDevice, err error) {
err = binary.Read(r, binary.LittleEndian, &d)
return
}
type IPC struct {
LinkCount uint32
}
type EIPC struct {
IPC
XattrInd uint32
}
func ReadIPC(r io.Reader) (i IPC, err error) {
err = binary.Read(r, binary.LittleEndian, &i)
return
}
func ReadEIPC(r io.Reader) (i EIPC, err error) {
err = binary.Read(r, binary.LittleEndian, &i)
return
}
-128
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@@ -1,128 +0,0 @@
package inode
import (
"encoding/binary"
"errors"
"io"
"strconv"
)
//Inode holds an inode. Header is the header that's common for all inodes.
//
//Info holds the actual Inode. Due to each inode type being a different type, it's store as an interface{}
type Inode struct {
Header
Info interface{} //Info is the parsed specific data. It's type is defined by Type.
}
//ProcessInode tries to read an inode from the BlockReader
func ProcessInode(br io.Reader, blockSize uint32) (*Inode, error) {
var in Inode
err := binary.Read(br, binary.LittleEndian, &in.Header)
if err != nil {
return nil, err
}
switch in.Type {
case DirType:
var inode Dir
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case FileType:
var inode File
inode, err = NewFile(br, blockSize)
if err != nil {
return nil, err
}
in.Info = inode
case SymType:
var inode Sym
inode, err = NewSymlink(br)
if err != nil {
return nil, err
}
in.Info = inode
case BlockDevType:
var inode Device
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case CharDevType:
var inode Device
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case FifoType:
var inode IPC
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case SocketType:
var inode IPC
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case ExtDirType:
var inode ExtDir
inode, err = NewExtendedDirectory(br)
if err != nil {
return nil, err
}
in.Info = inode
case ExtFileType:
var inode ExtFile
inode, err = NewExtendedFile(br, blockSize)
if err != nil {
return nil, err
}
in.Info = inode
case ExtSymType:
var inode ExtSym
inode, err = NewExtendedSymlink(br)
if err != nil {
return nil, err
}
in.Info = inode
case ExtBlockDeviceType:
var inode ExtDevice
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case ExtCharDeviceType:
var inode ExtDevice
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case ExtFifoType:
var inode ExtIPC
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
case ExtSocketType:
var inode ExtIPC
err = binary.Read(br, binary.LittleEndian, &inode)
if err != nil {
return nil, err
}
in.Info = inode
default:
return nil, errors.New("Unsupported inode type: " + strconv.Itoa(int(in.Type)))
}
return &in, nil
}
+46
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@@ -0,0 +1,46 @@
package inode
import (
"encoding/binary"
"io"
)
type symlinkInit struct {
LinkCount uint32
TargetSize uint32
}
type Symlink struct {
symlinkInit
Target []byte
}
type ESymlink struct {
symlinkInit
Target []byte
XattrInd uint32
}
func ReadSym(r io.Reader) (s Symlink, err error) {
err = binary.Read(r, binary.LittleEndian, &s.symlinkInit)
if err != nil {
return
}
s.Target = make([]byte, s.TargetSize)
err = binary.Read(r, binary.LittleEndian, &s.Target)
return
}
func ReadESym(r io.Reader) (s ESymlink, err error) {
err = binary.Read(r, binary.LittleEndian, &s.symlinkInit)
if err != nil {
return
}
s.Target = make([]byte, s.TargetSize)
err = binary.Read(r, binary.LittleEndian, &s.Target)
if err != nil {
return
}
err = binary.Read(r, binary.LittleEndian, &s.XattrInd)
return
}
+60
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@@ -0,0 +1,60 @@
package metadata
import (
"encoding/binary"
"io"
"github.com/CalebQ42/squashfs/internal/decompress"
)
type Reader struct {
master io.Reader
cur io.Reader
d decompress.Decompressor
}
func NewReader(r io.Reader, d decompress.Decompressor) (*Reader, error) {
var out Reader
out.d = d
out.master = r
return &out, out.Advance()
}
func (r *Reader) Advance() error {
if clr, ok := r.cur.(io.Closer); ok {
clr.Close()
}
var size uint16
err := binary.Read(r.master, binary.LittleEndian, &size)
if err != nil {
return err
}
comp := size&0x8000 != 0x8000
size &^= 0x8000
r.cur = io.LimitReader(r.master, int64(size))
if comp {
r.cur, err = r.d.Reader(r.cur)
if err != nil {
return err
}
}
return nil
}
func (r Reader) Read(p []byte) (n int, err error) {
n, err = r.cur.Read(p)
if err == io.EOF {
err = r.Advance()
if err != nil {
return
}
var tmpN int
tmp := make([]byte, len(p)-n)
tmpN, err = r.Read(tmp)
for i := range tmp {
p[n+i] = tmp[i]
}
n += tmpN
}
return
}
-135
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@@ -1,135 +0,0 @@
package rawreader
import (
"bytes"
"errors"
"io"
)
func ConvertReader(r io.Reader) (RawReader, error) {
if rr, ok := r.(RawReader); ok {
return rr, nil
}
if rs, is := r.(io.ReadSeeker); is {
return &fromReadSeeker{
ReadSeeker: rs,
}, nil
}
buf := new(bytes.Buffer)
_, err := io.Copy(buf, r)
if err != nil {
return nil, err
}
return &fromReader{
data: buf.Bytes(),
}, nil
}
func ConvertReaderAt(r io.ReaderAt) RawReader {
if rr, ok := r.(RawReader); ok {
return rr
}
return &fromReaderAt{
ReaderAt: r,
}
}
//TODO: Add way to discard data from fromReader
//RawReader implements the needed interfaces for reading a squashfs archive.
type RawReader interface {
io.ReadSeeker
io.ReaderAt
}
type fromReader struct {
data []byte
off int
}
func (r *fromReader) ReadAt(p []byte, off int64) (n int, err error) {
n = len(p)
if int(off)+len(p) > len(r.data) {
n = len(r.data) - int(off)
err = io.EOF
}
if n < 0 {
n = 0
}
for i := 0; i < n; i++ {
p[i] = r.data[int(off)+i]
}
return
}
func (r *fromReader) Seek(off int64, whence int) (n int64, err error) {
switch whence {
case io.SeekEnd:
r.off = len(r.data) - int(off)
if r.off < 0 {
r.off = 0
err = io.EOF
}
case io.SeekCurrent:
r.off += int(off)
case io.SeekStart:
r.off = int(off)
}
if r.off > len(r.data) {
r.off = len(r.data)
return int64(r.off), io.EOF
}
return int64(r.off), err
}
func (r *fromReader) Read(p []byte) (n int, err error) {
n = len(p)
if r.off+len(p) > len(r.data) {
n = len(r.data) - r.off
err = io.EOF
}
if n < 0 {
n = 0
}
for i := 0; i < n; i++ {
p[i] = r.data[r.off+i]
}
return
}
type fromReadSeeker struct {
io.ReadSeeker
}
func (r *fromReadSeeker) ReadAt(p []byte, off int64) (n int, err error) {
tmp, _ := r.Seek(0, io.SeekCurrent)
defer r.Seek(tmp, io.SeekStart)
_, err = r.Seek(off, io.SeekStart)
if err != nil {
return
}
return r.Read(p)
}
type fromReaderAt struct {
io.ReaderAt
off int
}
func (r *fromReaderAt) Read(p []byte) (n int, err error) {
n, err = r.ReadAt(p, int64(r.off))
r.off += n
return
}
func (r *fromReaderAt) Seek(off int64, whence int) (n int64, err error) {
switch whence {
case io.SeekEnd:
return 0, errors.New("cannot SeekEnd RawReader")
case io.SeekCurrent:
r.off += int(off)
case io.SeekStart:
r.off = int(off)
}
return int64(r.off), nil
}
+25
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@@ -0,0 +1,25 @@
package toreader
import "io"
type Reader struct {
r io.ReaderAt
off int64
}
func NewReader(r io.ReaderAt, start int64) *Reader {
return &Reader{
r: r,
off: start,
}
}
func (r *Reader) Read(p []byte) (n int, err error) {
n, err = r.r.ReadAt(p, r.off)
r.off += int64(n)
return
}
func (r Reader) Offset() int64 {
return r.off
}
+23
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@@ -0,0 +1,23 @@
package toreader
import "io"
type ReaderAt struct {
d []byte
}
func NewReaderAt(r io.Reader) (ra ReaderAt, err error) {
ra.d, err = io.ReadAll(r)
return
}
func (r ReaderAt) ReadAt(p []byte, off int64) (n int, err error) {
if int(off) >= len(r.d) {
return 0, io.EOF
}
n = copy(p, r.d[off:])
if n != len(p) {
err = io.EOF
}
return
}