Caleb Gardner
71 lines
1.6 KiB
Go
71 lines
1.6 KiB
Go
package squashfs
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"errors"
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/CalebQ42/GoSquashfs/internal/directory"
|
|
"github.com/CalebQ42/GoSquashfs/internal/inode"
|
|
)
|
|
|
|
const (
|
|
magic = 0x73717368
|
|
)
|
|
|
|
type Reader struct {
|
|
r io.ReaderAt
|
|
super Superblock
|
|
flags SuperblockFlags
|
|
decompressor Decompressor
|
|
dirs []*directory.Directory
|
|
}
|
|
|
|
func NewSquashfsReader(r io.ReaderAt) (*Reader, error) {
|
|
var rdr Reader
|
|
rdr.r = r
|
|
err := binary.Read(io.NewSectionReader(rdr.r, 0, int64(binary.Size(rdr.super))), binary.LittleEndian, &rdr.super)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if rdr.super.Magic != magic {
|
|
return nil, errors.New("doesn't have magic number, probably isn't a squashfs")
|
|
}
|
|
rdr.flags = rdr.super.GetFlags()
|
|
switch rdr.super.CompressionType {
|
|
case gzipCompression:
|
|
rdr.decompressor = &ZlibDecompressor{}
|
|
default:
|
|
return nil, errors.New("Unsupported compression type")
|
|
}
|
|
if rdr.flags.CompressorOptions {
|
|
//TODO: parse compressor options
|
|
fmt.Println("Compressor options is NOT currently supported")
|
|
return nil, errors.New("Has compressor options")
|
|
}
|
|
return &rdr, nil
|
|
}
|
|
|
|
func (r *Reader) readDirTable() error {
|
|
inoderdr, err := r.NewBlockReaderFromInodeRef(r.super.RootInodeRef)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
i, err := inode.ProcessInode(inoderdr, r.super.BlockSize)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
inDir := i.Info.(inode.BasicDirectory)
|
|
dirrdr, err := r.NewBlockReader(int64(r.super.DirTableStart) + int64(inDir.DirectoryIndex))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
dir, err := directory.NewDirectory(dirrdr)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
fmt.Println("Entries", len(dir.Entries))
|
|
return nil
|
|
}
|