Clean path before checking if valid.

v0.6.0 fixes

.github/FUNDING.yml

@@ -0,0 +1,3 @@
+# These are supported funding model platforms
+
+github: CalebQ42

README.md

@@ -4,15 +4,19 @@
 
 A PURE Go library to read and write squashfs.
 
-Currently has support for reading squashfs files and extracting files and folders. Supports all compression types except LZO, but additional compression options are hit or miss.
-
-The only major thing missing from squashfs reading is Xattr parsing.
+Currently has support for reading squashfs files and extracting files and folders.
 
 Special thanks to <https://dr-emann.github.io/squashfs/> for some VERY important information in an easy to understand format.
 Thanks also to [distri's squashfs library](https://github.com/distr1/distri/tree/master/internal/squashfs) as I referenced it to figure some things out (and double check others).
 
-## Performane
-
-This library, decompressing the firefox AppImage and using go tests, takes about twice as long as `unsquashfs` on my quad core laptop. (~1 second with the libarary and about half a second with `unsquashfs`)
-
 ## [TODO](https://github.com/CalebQ42/squashfs/projects/1?fullscreen=true)
+
+## Limitations
+
+* No Xattr parsing. This is simply because I haven't done any research on it and how to apply these in a pure go way.
+
+## Performance
+
+This library, decompressing the Firefox AppImage and using go tests, takes about twice as long as `unsquashfs` on my quad core laptop. (~1 second with the library and about half a second with `unsquashfs`).
+
+**My recents tests have shown the Firefox AppImage might be an outlier and this library might be considerably slower (4x ~ 6x time slower then `unsquashfs`)**

compress.go

@@ -1,17 +0,0 @@
-package squashfs
-
-import "reflect"
-
-func (w *Writer) compressData(data []byte) ([]byte, error) {
-	if reflect.DeepEqual(data, make([]byte, len(data))) {
-		return nil, nil
-	}
-	compressedData, err := w.compressor.Compress(data)
-	if err != nil {
-		return nil, err
-	}
-	if len(data) <= len(compressedData) {
-		return data, nil
-	}
-	return compressedData, nil
-}

datareader.go

@@ -1,247 +0,0 @@
-package squashfs
-
-import (
-	"bytes"
-	"errors"
-	"io"
-
-	"github.com/CalebQ42/squashfs/internal/inode"
-)
-
-var (
-	//ErrInodeNotFile is given when giving an inode, but the function requires a file inode.
-	errInodeNotFile = errors.New("Given inode is NOT a file type")
-	//ErrInodeOnlyFragment is given when trying to make a DataReader from an inode, but the inode only had data in a fragment
-	errInodeOnlyFragment = errors.New("Given inode ONLY has fragment data")
-)
-
-//DataReader reads data from data blocks.
-type dataReader struct {
-	r             *Reader
-	curData       []byte
-	sizes         []uint32
-	offset        int64 //offset relative to the beginning of the squash file
-	curBlock      int   //Which block in sizes is currently cached
-	curReadOffset int   //offset relative to the currently cached data
-}
-
-//NewDataReader creates a new data reader at the given offset, with the blocks defined by sizes
-func (r *Reader) newDataReader(offset int64, sizes []uint32) (*dataReader, error) {
-	var dr dataReader
-	dr.r = r
-	dr.offset = offset
-	dr.sizes = sizes
-	err := dr.readCurBlock()
-	if err != nil {
-		return nil, err
-	}
-	return &dr, nil
-}
-
-//NewDataReaderFromInode creates a new DataReader from a given inode. Inode must be of BasicFile or ExtendedFile types
-func (r *Reader) newDataReaderFromInode(i *inode.Inode) (*dataReader, error) {
-	var rdr dataReader
-	rdr.r = r
-	switch i.Type {
-	case inode.FileType:
-		fil := i.Info.(inode.File)
-		if fil.BlockStart == 0 {
-			return nil, errInodeOnlyFragment
-		}
-		rdr.offset = int64(fil.BlockStart)
-		for _, sizes := range fil.BlockSizes {
-			rdr.sizes = append(rdr.sizes, sizes)
-		}
-		if fil.Fragmented {
-			rdr.sizes = rdr.sizes[:len(rdr.sizes)-1]
-		}
-	case inode.ExtFileType:
-		fil := i.Info.(inode.ExtFile)
-		if fil.BlockStart == 0 {
-			return nil, errInodeOnlyFragment
-		}
-		rdr.offset = int64(fil.BlockStart)
-		for _, sizes := range fil.BlockSizes {
-			rdr.sizes = append(rdr.sizes, sizes)
-		}
-		if fil.Fragmented {
-			rdr.sizes = rdr.sizes[:len(rdr.sizes)-1]
-		}
-	default:
-		return nil, errInodeNotFile
-	}
-	err := rdr.readCurBlock()
-	if err != nil {
-		return nil, err
-	}
-	return &rdr, nil
-}
-
-//removed the compression bit from a data block size
-func actualDataSize(size uint32) uint32 {
-	return size &^ (1 << 24)
-}
-
-func (d *dataReader) readNextBlock() error {
-	d.curBlock++
-	if d.curBlock >= len(d.sizes) {
-		d.curBlock--
-		return io.EOF
-	}
-	err := d.readCurBlock()
-	if err != nil {
-		d.curBlock--
-		d.readCurBlock()
-		return err
-	}
-	return nil
-}
-
-func (d *dataReader) readBlockAt(offset int64, size uint32) ([]byte, error) {
-	compressed := size&(1<<24) != (1 << 24)
-	size = size &^ (1 << 24)
-	if d.sizes[d.curBlock] == 0 {
-		return make([]byte, d.r.super.BlockSize), nil
-	}
-	sec := io.NewSectionReader(d.r.r, offset, int64(size))
-	if compressed {
-		btys, err := d.r.decompressor.Decompress(sec)
-		if err != nil {
-			return nil, err
-		}
-		return btys, nil
-	}
-	var buf bytes.Buffer
-	_, err := io.Copy(&buf, sec)
-	if err != nil {
-		return nil, err
-	}
-	return buf.Bytes(), nil
-}
-
-func (d *dataReader) offsetForBlock(index int) int64 {
-	out := d.offset
-	for i := 0; i < index; i++ {
-		out += int64(actualDataSize(d.sizes[i]))
-	}
-	return out
-}
-
-func (d *dataReader) readCurBlock() error {
-	if d.curBlock >= len(d.sizes) {
-		return io.EOF
-	}
-	offset := d.offsetForBlock(d.curBlock)
-	data, err := d.readBlockAt(offset, d.sizes[d.curBlock])
-	if err != nil {
-		return err
-	}
-	d.curData = data
-	return nil
-}
-
-func (d *dataReader) Read(p []byte) (int, error) {
-	if d.curData == nil {
-		err := d.readCurBlock()
-		if err != nil {
-			return 0, err
-		}
-	}
-	if d.curReadOffset+len(p) <= len(d.curData) {
-		for i := 0; i < len(p); i++ {
-			p[i] = d.curData[d.curReadOffset+i]
-		}
-		d.curReadOffset += len(p)
-		return len(p), nil
-	}
-	read := 0
-	for read < len(p) {
-		if d.curReadOffset == len(d.curData) {
-			err := d.readNextBlock()
-			if err != nil {
-				return read, err
-			}
-			d.curReadOffset = 0
-		}
-		for ; read < len(p); read++ {
-			if d.curReadOffset < len(d.curData) {
-				p[read] = d.curData[d.curReadOffset]
-			} else {
-				break
-			}
-			d.curReadOffset++
-		}
-	}
-	if read != len(p) {
-		return read, errors.New("Didn't read enough data")
-	}
-	return read, nil
-}
-
-// WriteTo writes all the data in the datablock to the writer. MUST BE USED ON A FRESH DATA READER.
-func (d *dataReader) WriteTo(w io.Writer) (int64, error) {
-	type dataCache struct {
-		err   error
-		data  []byte
-		index int
-	}
-	dataChan := make(chan *dataCache)
-	for i := range d.sizes {
-		go func(index int, c chan *dataCache) {
-			var cache dataCache
-			cache.index = index
-			defer func() {
-				c <- &cache
-			}()
-			data, err := d.readBlockAt(d.offsetForBlock(index), d.sizes[index])
-			if err != nil {
-				cache.err = err
-				return
-			}
-			cache.data = data
-			return
-		}(i, dataChan)
-	}
-	curIndex := 0
-	totalWrite := int64(0)
-	var backlog []*dataCache
-mainLoop:
-	for {
-		if curIndex == len(d.sizes) {
-			return totalWrite, nil
-		}
-		if len(backlog) > 0 {
-			for i, cache := range backlog {
-				if cache.index == curIndex {
-					writen, err := w.Write(cache.data)
-					totalWrite += int64(writen)
-					if err != nil {
-						return totalWrite, err
-					}
-					if len(backlog) > 0 {
-						backlog[i] = backlog[len(backlog)-1]
-						backlog = backlog[:len(backlog)-1]
-					} else {
-						backlog = nil
-					}
-					curIndex++
-					continue mainLoop
-				}
-			}
-		}
-		cache := <-dataChan
-		if cache.err != nil {
-			return totalWrite, cache.err
-		}
-		if cache.index == curIndex {
-			writen, err := w.Write(cache.data)
-			totalWrite += int64(writen)
-			if err != nil {
-				return totalWrite, err
-			}
-			curIndex++
-		} else {
-			backlog = append(backlog, cache)
-		}
-	}
-}

file.go

@@ -1,555 +0,0 @@
-package squashfs
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"os"
-	"path"
-	"strings"
-	"time"
-
-	"github.com/CalebQ42/squashfs/internal/directory"
-	"github.com/CalebQ42/squashfs/internal/inode"
-)
-
-var (
-	//ErrNotDirectory is returned when you're trying to do directory things with a non-directory
-	errNotDirectory = errors.New("File is not a directory")
-	//ErrNotFile is returned when you're trying to do file things with a directory
-	errNotFile = errors.New("File is not a file")
-	//ErrNotReading is returned when running functions that are only meant to be used when reading a squashfs
-	errNotReading = errors.New("Function only supported when reading a squashfs")
-	//ErrBrokenSymlink is returned when using ExtractWithOptions with the unbreakSymlink set to true, but the symlink's file cannot be extracted.
-	ErrBrokenSymlink = errors.New("Extracted symlink is probably broken")
-)
-
-//File is the main way to interact with files within squashfs, or when putting files into a squashfs.
-//File can be either a file or folder. When reading from a squashfs, it reads from the datablocks.
-//When writing, this holds the information on WHERE the file will be placed inside the archive.
-//
-//Implements os.FileInfo and io.ReadCloser
-type File struct {
-	Reader  io.Reader
-	Parent  *File
-	r       *Reader //Underlying reader. When writing, will probably be an os.File. When reading this is kept nil UNTIL reading to save memory.
-	in      *inode.Inode
-	name    string
-	path    string
-	filType int //The file's type, using inode types.
-
-}
-
-//get a File from a directory.entry
-func (r *Reader) newFileFromDirEntry(entry *directory.Entry) (fil *File, err error) {
-	fil = new(File)
-	fil.in, err = r.getInodeFromEntry(entry)
-	if err != nil {
-		return nil, err
-	}
-	fil.name = entry.Name
-	fil.r = r
-	fil.filType = fil.in.Type
-	return
-}
-
-//Name is the file's name
-func (f *File) Name() string {
-	return f.name
-}
-
-//Size is the complete size of the file. Zero if it's not a file.
-func (f *File) Size() int64 {
-	switch f.filType {
-	case inode.FileType:
-		return int64(f.in.Info.(inode.File).Size)
-	case inode.ExtFileType:
-		return int64(f.in.Info.(inode.ExtFile).Size)
-	default:
-		return 0
-	}
-}
-
-//ModTime is the time of last modification.
-func (f *File) ModTime() time.Time {
-	return time.Unix(int64(f.in.Header.ModifiedTime), 0)
-}
-
-//Sys returns the underlying reader, file.Reader. If the reader isn't initialized, it will initialize it.
-//If called on something other then a file, returns nil.
-func (f *File) Sys() interface{} {
-	if f.IsFile() {
-		if f.Reader == nil && f.r != nil {
-			var err error
-			f.Reader, err = f.r.newFileReader(f.in)
-			if err != nil {
-				return nil
-			}
-		}
-		return f.Reader
-	}
-	return nil
-}
-
-//GetChildren returns a *squashfs.File slice of every direct child of the directory. If the File is not a directory, will return ErrNotDirectory
-func (f *File) GetChildren() (children []*File, err error) {
-	children = make([]*File, 0)
-	if f.r == nil {
-		return nil, errNotReading
-	}
-	if !f.IsDir() {
-		return nil, errNotDirectory
-	}
-	dir, err := f.r.readDirFromInode(f.in)
-	if err != nil {
-		return
-	}
-	var fil *File
-	for _, entry := range dir.Entries {
-		fil, err = f.r.newFileFromDirEntry(&entry)
-		if err != nil {
-			return
-		}
-		fil.Parent = f
-		if f.name != "" {
-			fil.path = f.Path()
-		}
-		children = append(children, fil)
-	}
-	return
-}
-
-//GetChildrenRecursively returns ALL children. Goes down ALL folder paths.
-func (f *File) GetChildrenRecursively() (children []*File, err error) {
-	children = make([]*File, 0)
-	if f.r == nil {
-		return nil, errNotReading
-	}
-	if !f.IsDir() {
-		return nil, errNotDirectory
-	}
-	children, err = f.GetChildren()
-	if err != nil {
-		return
-	}
-	var childFolders []*File
-	for _, child := range children {
-		if child.IsDir() {
-			childFolders = append(childFolders, child)
-		}
-	}
-	foldChil := make(chan []*File)
-	errChan := make(chan error)
-	for _, folds := range childFolders {
-		go func(fil *File) {
-			childs, err := fil.GetChildrenRecursively()
-			errChan <- err
-			foldChil <- childs
-		}(folds)
-	}
-	for range childFolders {
-		err = <-errChan
-		if err != nil {
-			return
-		}
-		children = append(children, <-foldChil...)
-	}
-	return
-}
-
-//Path returns the path of the file within the archive.
-func (f *File) Path() string {
-	if f.name == "" {
-		return f.path
-	}
-	return f.path + "/" + f.name
-}
-
-//GetFileAtPath tries to return the File at the given path, relative to the file.
-//Returns nil if called on something other then a folder, OR if the path goes oustide the archive.
-//Allows wildcards supported by path.Match (namely * and ?).
-func (f *File) GetFileAtPath(dirPath string) *File {
-	if dirPath == "" {
-		return f
-	}
-	dirPath = strings.TrimSuffix(strings.TrimPrefix(dirPath, "/"), "/")
-	if dirPath != "" && !f.IsDir() {
-		return nil
-	}
-	for strings.HasSuffix(dirPath, "./") {
-		//since you can TECHNICALLY have an infinite amount of ./ and it would still be valid.
-		dirPath = strings.TrimPrefix(dirPath, "./")
-	}
-	split := strings.Split(dirPath, "/")
-	if split[0] == ".." && f.name == "" {
-		return nil
-	} else if split[0] == ".." {
-		if f.Parent != nil {
-			return f.Parent.GetFileAtPath(strings.Join(split[1:], "/"))
-		}
-		return nil
-	}
-	children, err := f.GetChildren()
-	if err != nil {
-		return nil
-	}
-	for _, child := range children {
-		eq, _ := path.Match(split[0], child.name)
-		if eq {
-			return child.GetFileAtPath(strings.Join(split[1:], "/"))
-		}
-	}
-	return nil
-}
-
-//IsDir returns if the file is a directory.
-func (f *File) IsDir() bool {
-	return f.filType == inode.DirType || f.filType == inode.ExtDirType
-}
-
-//IsSymlink returns if the file is a symlink.
-func (f *File) IsSymlink() bool {
-	return f.filType == inode.SymType || f.filType == inode.ExtSymlinkType
-}
-
-//IsFile returns if the file is a file.
-func (f *File) IsFile() bool {
-	return f.filType == inode.FileType || f.filType == inode.ExtFileType
-}
-
-//SymlinkPath returns the path the symlink is pointing to. If the file ISN'T a symlink, will return an empty string.
-//If a path begins with "/" then the symlink is pointing to an absolute path (starting from root, and not a file inside the archive)
-func (f *File) SymlinkPath() string {
-	switch f.filType {
-	case inode.SymType:
-		return f.in.Info.(inode.Sym).Path
-	case inode.ExtSymlinkType:
-		return f.in.Info.(inode.Sym).Path
-	default:
-		return ""
-	}
-}
-
-//GetSymlinkFile tries to return the squashfs.File associated with the symlink. If the file isn't a symlink
-//or the symlink points to a location outside the archive, nil is returned.
-func (f *File) GetSymlinkFile() *File {
-	if !f.IsSymlink() {
-		return nil
-	}
-	if strings.HasSuffix(f.SymlinkPath(), "/") {
-		return nil
-	}
-	return f.Parent.GetFileAtPath(f.SymlinkPath())
-}
-
-//GetSymlinkFileRecursive tries to return the squasfs.File associated with the symlink. It will recursively
-//try to get the symlink's file. This will return either a non-symlink File, or nil.
-func (f *File) GetSymlinkFileRecursive() *File {
-	if !f.IsSymlink() {
-		return nil
-	}
-	if strings.HasSuffix(f.SymlinkPath(), "/") {
-		return nil
-	}
-	sym := f
-	for {
-		sym = sym.GetSymlinkFile()
-		if sym == nil {
-			return nil
-		}
-		if !sym.IsSymlink() {
-			return sym
-		}
-	}
-}
-
-//Mode returns the os.FileMode of the File. Sets mode bits for directories and symlinks.
-func (f *File) Mode() os.FileMode {
-	mode := os.FileMode(f.in.Header.Permissions)
-	switch {
-	case f.IsDir():
-		mode = mode | os.ModeDir
-	case f.IsSymlink():
-		mode = mode | os.ModeSymlink
-	}
-	return mode
-}
-
-//ExtractTo extracts the file to the given path. This is the same as ExtractWithOptions(path, false, false, os.ModePerm, false).
-//Will NOT try to keep symlinks valid, folders extracted will have the permissions set by the squashfs, but the folder to make path will have full permissions (777).
-//
-//Will try it's best to extract all files, and if any errors come up, they will be appended to the error slice that's returned.
-func (f *File) ExtractTo(path string) []error {
-	return f.ExtractWithOptions(path, false, false, os.ModePerm, false)
-}
-
-//ExtractSymlink is similar to ExtractTo, but when it extracts a symlink, it instead extracts the file associated with the symlink in it's place.
-//This is the same as ExtractWithOptions(path, true, false, os.ModePerm, false)
-func (f *File) ExtractSymlink(path string) []error {
-	return f.ExtractWithOptions(path, true, false, os.ModePerm, false)
-}
-
-//ExtractWithOptions will extract the file to the given path, while allowing customization on how it works. ExtractTo is the "default" options.
-//Will try it's best to extract all files, and if any errors come up, they will be appended to the error slice that's returned.
-//Should only return multiple errors if extracting a folder.
-//
-//If dereferenceSymlink is set, instead of extracting a symlink, it will extract the file the symlink is pointed to in it's place.
-//If both dereferenceSymlink and unbreakSymlink is set, dereferenceSymlink takes precendence.
-//
-//If unbreakSymlink is set, it will also try to extract the symlink's associated file. WARNING: the symlink's file may have to go up the directory to work.
-//If unbreakSymlink is set and the file cannot be extracted, a ErrBrokenSymlink will be appended to the returned error slice.
-//
-//folderPerm only applies to the folders created to get to path. Folders from the archive are given the correct permissions defined by the archive.
-func (f *File) ExtractWithOptions(path string, dereferenceSymlink, unbreakSymlink bool, folderPerm os.FileMode, verbose bool) (errs []error) {
-	errs = make([]error, 0)
-	err := os.MkdirAll(path, folderPerm)
-	if err != nil {
-		return []error{err}
-	}
-	switch {
-	case f.IsDir():
-		if f.name != "" {
-			//TODO: check if folder is present, and if so, try to set it's permission
-			err = os.Mkdir(path+"/"+f.name, os.ModePerm)
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while making: ", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-				return
-			}
-			fil, err := os.Open(path + "/" + f.name)
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while opening:", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-				return
-			}
-			fil.Chown(int(f.r.idTable[f.in.Header.UID]), int(f.r.idTable[f.in.Header.GID]))
-			//don't mention anything when it fails. Because it fails often. Probably has something to do about uid & gid 0
-			// if err != nil {
-			// 	if verbose {
-			// 		fmt.Println("Error while changing owner:", path+"/"+f.Name)
-			// 		fmt.Println(err)
-			// 	}
-			// 	errs = append(errs, err)
-			// }
-			err = fil.Chmod(f.Mode())
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while changing owner:", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-			}
-		}
-		children, err := f.GetChildren()
-		if err != nil {
-			if verbose {
-				fmt.Println("Error getting children for:", f.Path())
-				fmt.Println(err)
-			}
-			errs = append(errs, err)
-			return
-		}
-		finishChan := make(chan []error)
-		for _, child := range children {
-			go func(child *File) {
-				if f.name == "" {
-					finishChan <- child.ExtractWithOptions(path, dereferenceSymlink, unbreakSymlink, folderPerm, verbose)
-				} else {
-					finishChan <- child.ExtractWithOptions(path+"/"+f.name, dereferenceSymlink, unbreakSymlink, folderPerm, verbose)
-				}
-			}(child)
-		}
-		for range children {
-			errs = append(errs, (<-finishChan)...)
-		}
-		return
-	case f.IsFile():
-		fil, err := os.Create(path + "/" + f.name)
-		if os.IsExist(err) {
-			err = os.Remove(path + "/" + f.name)
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while making:", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-				return
-			}
-			fil, err = os.Create(path + "/" + f.name)
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while making:", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-				return
-			}
-		} else if err != nil {
-			if verbose {
-				fmt.Println("Error while making:", path+"/"+f.name)
-				fmt.Println(err)
-			}
-			errs = append(errs, err)
-			return
-		} //Since we will be reading from the file
-		if f.Reader == nil && f.r != nil {
-			f.Reader, err = f.r.newFileReader(f.in)
-			if err != nil {
-				if verbose {
-					fmt.Println("Error while Copying data to:", path+"/"+f.name)
-					fmt.Println(err)
-				}
-				errs = append(errs, err)
-				return
-			}
-		}
-		_, err = io.Copy(fil, f.Reader)
-		if err != nil {
-			if verbose {
-				fmt.Println("Error while Copying data to:", path+"/"+f.name)
-				fmt.Println(err)
-			}
-			errs = append(errs, err)
-			return
-		}
-		fil.Chown(int(f.r.idTable[f.in.Header.UID]), int(f.r.idTable[f.in.Header.GID]))
-		//don't mention anything when it fails. Because it fails often. Probably has something to do about uid & gid 0
-		// if err != nil {
-		// 	if verbose {
-		// 		fmt.Println("Error while changing owner:", path+"/"+f.Name)
-		// 		fmt.Println(err)
-		// 	}
-		// 	errs = append(errs, err)
-		// 	return
-		// }
-		err = fil.Chmod(f.Mode())
-		if err != nil {
-			if verbose {
-				fmt.Println("Error while setting permissions for:", path+"/"+f.name)
-				fmt.Println(err)
-			}
-			errs = append(errs, err)
-		}
-		return
-	case f.IsSymlink():
-		symPath := f.SymlinkPath()
-		if dereferenceSymlink {
-			fil := f.GetSymlinkFile()
-			if fil == nil {
-				if verbose {
-					fmt.Println("Symlink path(", symPath, ") is outside the archive:"+path+"/"+f.name)
-				}
-				return
-			}
-			fil.name = f.name
-			extracSymErrs := fil.ExtractWithOptions(path, dereferenceSymlink, unbreakSymlink, folderPerm, verbose)
-			if len(extracSymErrs) > 0 {
-				if verbose {
-					fmt.Println("Error(s) while extracting the symlink's file:", path+"/"+f.name)
-					fmt.Println(extracSymErrs)
-				}
-				errs = append(errs, extracSymErrs...)
-			}
-			return
-		} else if unbreakSymlink {
-			fil := f.GetSymlinkFile()
-			if fil != nil {
-				symPath = path + "/" + symPath
-				paths := strings.Split(symPath, "/")
-				extracSymErrs := fil.ExtractWithOptions(strings.Join(paths[:len(paths)-1], "/"), dereferenceSymlink, unbreakSymlink, folderPerm, verbose)
-				if len(extracSymErrs) > 0 {
-					if verbose {
-						fmt.Println("Error(s) while extracting the symlink's file:", path+"/"+f.name)
-						fmt.Println(extracSymErrs)
-					}
-					errs = append(errs, extracSymErrs...)
-				}
-			} else {
-				if verbose {
-					fmt.Println("Symlink path(", symPath, ") is outside the archive:"+path+"/"+f.name)
-				}
-				return
-			}
-		}
-		err = os.Symlink(f.SymlinkPath(), path+"/"+f.name)
-		if err != nil {
-			if verbose {
-				fmt.Println("Error while making symlink:", path+"/"+f.name)
-				fmt.Println(err)
-			}
-			errs = append(errs, err)
-		}
-	}
-	return
-}
-
-//Read from the file. Doesn't do anything fancy, just pases it to the underlying io.Reader. If a directory, return io.EOF.
-func (f *File) Read(p []byte) (int, error) {
-	if !f.IsFile() {
-		return 0, io.EOF
-	}
-	var err error
-	if f.Reader == nil && f.r != nil {
-		f.Reader, err = f.r.newFileReader(f.in)
-		if err != nil {
-			return 0, err
-		}
-	}
-	return f.Reader.Read(p)
-}
-
-//ReadDirFromInode returns a fully populated Directory from a given Inode.
-//If the given inode is not a directory it returns an error.
-func (r *Reader) readDirFromInode(i *inode.Inode) (*directory.Directory, error) {
-	var offset uint32
-	var metaOffset uint16
-	var size uint32
-	switch i.Type {
-	case inode.DirType:
-		offset = i.Info.(inode.Dir).DirectoryIndex
-		metaOffset = i.Info.(inode.Dir).DirectoryOffset
-		size = uint32(i.Info.(inode.Dir).DirectorySize)
-	case inode.ExtDirType:
-		offset = i.Info.(inode.ExtDir).DirectoryIndex
-		metaOffset = i.Info.(inode.ExtDir).DirectoryOffset
-		size = i.Info.(inode.ExtDir).DirectorySize
-	default:
-		return nil, errors.New("Not a directory inode")
-	}
-	br, err := r.newMetadataReader(int64(r.super.DirTableStart + uint64(offset)))
-	if err != nil {
-		return nil, err
-	}
-	_, err = br.Seek(int64(metaOffset), io.SeekStart)
-	if err != nil {
-		return nil, err
-	}
-	dir, err := directory.NewDirectory(br, size)
-	if err != nil {
-		return dir, err
-	}
-	return dir, nil
-}
-
-//GetInodeFromEntry returns the inode associated with a given directory.Entry
-func (r *Reader) getInodeFromEntry(en *directory.Entry) (*inode.Inode, error) {
-	br, err := r.newMetadataReader(int64(r.super.InodeTableStart + uint64(en.Header.InodeOffset)))
-	if err != nil {
-		return nil, err
-	}
-	_, err = br.Seek(int64(en.Offset), io.SeekStart)
-	if err != nil {
-		return nil, err
-	}
-	i, err := inode.ProcessInode(br, r.super.BlockSize)
-	if err != nil {
-		return nil, err
-	}
-	return i, nil
-}

filereader.go

@@ -1,101 +0,0 @@
-package squashfs
-
-import (
-	"bytes"
-	"errors"
-	"io"
-
-	"github.com/CalebQ42/squashfs/internal/inode"
-)
-
-//FileReader provides a io.Reader interface for files within a squashfs archive
-type fileReader struct {
-	r            *Reader
-	data         *dataReader
-	in           *inode.Inode
-	fragmentData []byte
-	fragged      bool
-	fragOnly     bool
-	read         int
-	FileSize     int //FileSize is the total size of the given file
-}
-
-var (
-	//ErrPathIsNotFile returns when trying to read from a file, but the given path is NOT a file.
-	errPathIsNotFile = errors.New("The given path is not a file")
-)
-
-//ReadFile provides a squashfs.FileReader for the file at the given location.
-func (r *Reader) newFileReader(in *inode.Inode) (*fileReader, error) {
-	var rdr fileReader
-	rdr.in = in
-	if in.Type != inode.FileType && in.Type != inode.ExtFileType {
-		return nil, errPathIsNotFile
-	}
-	switch in.Type {
-	case inode.FileType:
-		fil := in.Info.(inode.File)
-		rdr.fragged = fil.Fragmented
-		rdr.fragOnly = fil.BlockStart == 0
-		rdr.FileSize = int(fil.Size)
-	case inode.ExtFileType:
-		fil := in.Info.(inode.ExtFile)
-		rdr.fragged = fil.Fragmented
-		rdr.fragOnly = fil.BlockStart == 0
-		rdr.FileSize = int(fil.Size)
-	}
-	var err error
-	if rdr.fragged {
-		rdr.fragmentData, err = r.getFragmentDataFromInode(in)
-		if err != nil {
-			return nil, err
-		}
-	}
-	if !rdr.fragOnly {
-		rdr.data, err = r.newDataReaderFromInode(in)
-	}
-	return &rdr, nil
-}
-
-func (f *fileReader) Read(p []byte) (int, error) {
-	if f.fragOnly {
-		n, err := bytes.NewBuffer(f.fragmentData[f.read:]).Read(p)
-		f.read += n
-		if err != nil {
-			return n, err
-		}
-		return n, nil
-	}
-	var read int
-	n, err := f.data.Read(p)
-	read += n
-	if f.fragged && err == io.EOF {
-		if f.fragmentData == nil {
-			f.fragmentData, err = f.r.getFragmentDataFromInode(f.in)
-		}
-		n, err = bytes.NewBuffer(f.fragmentData).Read(p[read:])
-		read += n
-		if err != nil {
-			return read, err
-		}
-	} else if err != nil {
-		return read, err
-	}
-	return read, nil
-}
-
-func (f *fileReader) WriteTo(w io.Writer) (int64, error) {
-	if f.fragOnly {
-		n, err := w.Write(f.fragmentData)
-		return int64(n), err
-	}
-	if !f.fragged {
-		return f.data.WriteTo(w)
-	}
-	n, err := f.data.WriteTo(w)
-	if err != nil {
-		return int64(n), err
-	}
-	nn, err := w.Write(f.fragmentData)
-	return int64(nn) + n, err
-}

fragment.go

@@ -1,80 +0,0 @@
-package squashfs
-
-import (
-	"encoding/binary"
-	"errors"
-	"io"
-
-	"github.com/CalebQ42/squashfs/internal/inode"
-)
-
-//FragmentEntry is an entry in the fragment table
-type fragmentEntry struct {
-	Start  uint64
-	Size   uint32
-	Unused uint32
-}
-
-//GetFragmentDataFromInode returns the fragment data for a given inode.
-//If the inode does not have a fragment, harmlessly returns an empty slice without an error.
-func (r *Reader) getFragmentDataFromInode(in *inode.Inode) ([]byte, error) {
-	var size uint32
-	var fragIndex uint32
-	var fragOffset uint32
-	if in.Type == inode.FileType {
-		bf := in.Info.(inode.File)
-		if !bf.Fragmented {
-			return make([]byte, 0), nil
-		}
-		if bf.BlockStart == 0 {
-			size = bf.Size
-		} else {
-			size = bf.BlockSizes[len(bf.BlockSizes)-1]
-		}
-		fragIndex = bf.FragmentIndex
-		fragOffset = bf.FragmentOffset
-	} else if in.Type == inode.ExtFileType {
-		bf := in.Info.(inode.ExtFile)
-		if !bf.Fragmented {
-			return make([]byte, 0), nil
-		}
-		if bf.BlockStart == 0 {
-			size = bf.Size
-		} else {
-			size = bf.BlockSizes[len(bf.BlockSizes)-1]
-		}
-		fragIndex = bf.FragmentIndex
-		fragOffset = bf.FragmentOffset
-	} else {
-		return nil, errors.New("Inode type not supported")
-	}
-	//reading the fragment entry first
-	fragEntryRdr, err := r.newMetadataReader(int64(r.fragOffsets[int(fragIndex/512)]))
-	if err != nil {
-		return nil, err
-	}
-	_, err = fragEntryRdr.Seek(int64(16*fragIndex), io.SeekStart)
-	if err != nil {
-		return nil, err
-	}
-	var entry fragmentEntry
-	err = binary.Read(fragEntryRdr, binary.LittleEndian, &entry)
-	if err != nil {
-		return nil, err
-	}
-	//now reading the actual fragment
-	dr, err := r.newDataReader(int64(entry.Start), []uint32{entry.Size})
-	if err != nil {
-		return nil, err
-	}
-	_, err = dr.Read(make([]byte, fragOffset))
-	if err != nil {
-		return nil, err
-	}
-	tmp := make([]byte, size)
-	err = binary.Read(dr, binary.LittleEndian, &tmp)
-	if err != nil {
-		return nil, err
-	}
-	return tmp, nil
-}

go.mod

@@ -1,18 +1,11 @@
 module github.com/CalebQ42/squashfs
 
-go 1.15
+go 1.19
 
 require (
-	github.com/CalebQ42/GoAppImage v0.4.0
-	github.com/adrg/xdg v0.2.3 // indirect
-	github.com/google/go-cmp v0.5.4 // indirect
-	github.com/gopherjs/gopherjs v0.0.0-20200217142428-fce0ec30dd00 // indirect
-	github.com/klauspost/compress v1.11.4
-	github.com/kr/text v0.2.0 // indirect
-	github.com/pierrec/lz4/v4 v4.1.2
-	github.com/smartystreets/assertions v1.2.0 // indirect
-	github.com/ulikunitz/xz v0.5.9
-	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
-	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
-	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
+	github.com/klauspost/compress v1.15.9
+	github.com/pierrec/lz4/v4 v4.1.15
+	github.com/rasky/go-lzo v0.0.0-20200203143853-96a758eda86e
+	github.com/therootcompany/xz v1.0.1
+	github.com/ulikunitz/xz v0.5.10
 )

go.sum

@@ -1,73 +1,10 @@
-github.com/CalebQ42/GoAppImage v0.4.0 h1:aF+Y/vyo/RGhoyZEW1CMY6WyRWrZZO4ydsRFAtIGnaY=
-github.com/CalebQ42/GoAppImage v0.4.0/go.mod h1:qHudJKAn/dlkNWNnH4h1YKXp29EZ7Bppsn7sNP2HuvU=
-github.com/adrg/xdg v0.2.2 h1:A7ZHKRz5KGOLJX/bg7IPzStryhvCzAE1wX+KWawPiAo=
-github.com/adrg/xdg v0.2.2/go.mod h1:7I2hH/IT30IsupOpKZ5ue7/qNi3CoKzD6tL3HwpaRMQ=
-github.com/adrg/xdg v0.2.3 h1:GxXngdYxNDkoUvZXjNJGwqZxWXi43MKbOOlA/00qZi4=
-github.com/adrg/xdg v0.2.3/go.mod h1:7I2hH/IT30IsupOpKZ5ue7/qNi3CoKzD6tL3HwpaRMQ=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
-github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
-github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.4 h1:L8R9j+yAqZuZjsqh/z+F1NCffTKKLShY6zXTItVIZ8M=
-github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1 h1:EGx4pi6eqNxGaHF6qqu48+N2wcFQ5qg5FXgOdqsJ5d8=
-github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
-github.com/gopherjs/gopherjs v0.0.0-20200217142428-fce0ec30dd00 h1:l5lAOZEym3oK3SQ2HBHWsJUfbNBiTXJDeW2QDxw9AQ0=
-github.com/gopherjs/gopherjs v0.0.0-20200217142428-fce0ec30dd00/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
-github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7C0MuV77Wo=
-github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
-github.com/klauspost/compress v1.11.4 h1:kz40R/YWls3iqT9zX9AHN3WoVsrAWVyui5sxuLqiXqU=
-github.com/klauspost/compress v1.11.4/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
-github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
-github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
-github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
-github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
-github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
-github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
-github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
-github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWbfPhv4DMiApHyliiK5xCTNVSPiaAs=
-github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
-github.com/pierrec/lz4/v4 v4.1.2 h1:qvY3YFXRQE/XB8MlLzJH7mSzBs74eA2gg52YTk6jUPM=
-github.com/pierrec/lz4/v4 v4.1.2/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d h1:zE9ykElWQ6/NYmHa3jpm/yHnI4xSofP+UP6SpjHcSeM=
-github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d/go.mod h1:OnSkiWE9lh6wB0YB77sQom3nweQdgAjqCqsofrRNTgc=
-github.com/smartystreets/assertions v1.2.0 h1:42S6lae5dvLc7BrLu/0ugRtcFVjoJNMC/N3yZFZkDFs=
-github.com/smartystreets/assertions v1.2.0/go.mod h1:tcbTF8ujkAEcZ8TElKY+i30BzYlVhC/LOxJk7iOWnoo=
-github.com/smartystreets/goconvey v1.6.4 h1:fv0U8FUIMPNf1L9lnHLvLhgicrIVChEkdzIKYqbNC9s=
-github.com/smartystreets/goconvey v1.6.4/go.mod h1:syvi0/a8iFYH4r/RixwvyeAJjdLS9QV7WQ/tjFTllLA=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
-github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/ulikunitz/xz v0.5.9 h1:RsKRIA2MO8x56wkkcd3LbtcE/uMszhb6DpRf+3uwa3I=
-github.com/ulikunitz/xz v0.5.9/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=
-go.lsp.dev/uri v0.3.0 h1:KcZJmh6nFIBeJzTugn5JTU6OOyG0lDOo3R9KwTxTYbo=
-go.lsp.dev/uri v0.3.0/go.mod h1:P5sbO1IQR+qySTWOCnhnK7phBx+W3zbLqSMDJNTw88I=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
-golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a h1:1BGLXjeY4akVXGgbC9HugT3Jv3hCI0z56oJR5vAMgBU=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/tools v0.0.0-20190328211700-ab21143f2384 h1:TFlARGu6Czu1z7q93HTxcP1P+/ZFC/IKythI5RzrnRg=
-golang.org/x/tools v0.0.0-20190328211700-ab21143f2384/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
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-gopkg.in/ini.v1 v1.62.0 h1:duBzk771uxoUuOlyRLkHsygud9+5lrlGjdFBb4mSKDU=
-gopkg.in/ini.v1 v1.62.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
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+github.com/klauspost/compress v1.15.9 h1:wKRjX6JRtDdrE9qwa4b/Cip7ACOshUI4smpCQanqjSY=
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+github.com/therootcompany/xz v1.0.1/go.mod h1:3K3UH1yCKgBneZYhuQUvJ9HPD19UEXEI0BWbMn8qNMY=
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+github.com/ulikunitz/xz v0.5.10/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=

internal/compression/gzip.go

@@ -1,75 +0,0 @@
-package compression
-
-import (
-	"bytes"
-	"compress/zlib"
-	"encoding/binary"
-	"io"
-)
-
-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
-}

internal/compression/lz4.go

@@ -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
-}

internal/compression/lzma.go

@@ -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
-}

internal/compression/types.go

@@ -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)
-}

internal/compression/xz.go

@@ -1,75 +0,0 @@
-package compression
-
-import (
-	"bytes"
-	"encoding/binary"
-	"io"
-
-	"github.com/ulikunitz/xz"
-)
-
-type xzInit struct {
-	DictionarySize int32
-	Filters        int32
-}
-
-//Xz is a Xz decompressor.
-type Xz struct {
-	DictionarySize int32
-	HasFilters     bool
-}
-
-//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
-	var init xzInit
-	err := binary.Read(rdr, binary.LittleEndian, &init)
-	if err != nil {
-		return nil, err
-	}
-	x.DictionarySize = init.DictionarySize
-	//TODO: When I can do filters, parse the filters
-	if init.Filters != 0 {
-		x.HasFilters = true
-	}
-	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)
-	if err != nil {
-		return nil, err
-	}
-	r.DictCap = int(x.DictionarySize)
-	err = r.Verify()
-	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 := xz.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
-}

internal/compression/zstd.go

@@ -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
-}

internal/data/fullreader.go

@@ -0,0 +1,145 @@
+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   func() (io.Reader, error)
+	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 func() (io.Reader, error)) {
+	r.fragRdr = rdr
+	r.sizes = append(r.sizes, 0)
+}
+
+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
+	var rdr io.ReadCloser
+	size := realSize(r.sizes[index])
+	if size == 0 {
+		out <- outDat{
+			i:    index,
+			err:  nil,
+			data: make([]byte, r.blockSize),
+		}
+		return
+	}
+	// rdr := io.LimitReader(toreader.NewReader(r.r, offset), int64(size))
+	if size == r.sizes[index] {
+		//Special workaround for zstd for increased performancce.
+		if zstd, ok := r.d.(*decompress.Zstd); ok {
+			dat = make([]byte, size)
+			_, err = r.r.ReadAt(dat, offset)
+			if err == nil {
+				dat, err = zstd.Decode(dat)
+			}
+		} else {
+			rdr, err = r.d.Reader(io.LimitReader(toreader.NewReader(r.r, offset), int64(size)))
+			if err == nil {
+				dat, err = io.ReadAll(rdr)
+			}
+		}
+	} else {
+		dat = make([]byte, size)
+		_, err = r.r.ReadAt(dat, offset)
+	}
+	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() {
+				rdr, e := r.fragRdr()
+				if err != nil {
+					out <- outDat{
+						i:   num - 1,
+						err: e,
+					}
+					return
+				}
+				dat, e := io.ReadAll(rdr)
+				out <- outDat{
+					i:    num - 1,
+					err:  e,
+					data: dat,
+				}
+				if clr, ok := rdr.(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
+}

internal/data/reader.go

@@ -0,0 +1,98 @@
+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
+	comRdr     io.Reader
+	blockSizes []uint32
+	blockSize  uint32
+	resetable  bool
+}
+
+func NewReader(r io.Reader, d decompress.Decompressor, blockSizes []uint32, blockSize uint32) *Reader {
+	return &Reader{
+		d:          d,
+		master:     r,
+		blockSizes: blockSizes,
+		blockSize:  blockSize,
+		resetable:  true,
+	}
+}
+
+func (r *Reader) AddFragment(rdr io.Reader) {
+	r.fragRdr = rdr
+	r.blockSizes = append(r.blockSizes, 0)
+}
+
+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] {
+				if r.d.Resetable() {
+					if r.comRdr == nil {
+						r.cur, err = r.d.Reader(r.cur)
+						if err != nil {
+							return
+						}
+					} else {
+						err = r.d.Reset(r.comRdr, r.cur)
+						r.cur = r.comRdr
+					}
+				} else {
+					r.cur, err = r.d.Reader(r.cur)
+				}
+			}
+		}
+	}
+	r.blockSizes = r.blockSizes[1:]
+	return
+}
+
+func (r *Reader) Read(p []byte) (n int, err error) {
+	if r.cur == nil {
+		err = r.advance()
+		if err != nil {
+			return
+		}
+	}
+	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
+}

internal/decompress/gzip.go

@@ -0,0 +1,19 @@
+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)
+}
+
+func (g GZip) Resetable() bool { return true }
+
+func (g GZip) Reset(old, src io.Reader) error {
+	return old.(zlib.Resetter).Reset(src, nil)
+}

internal/decompress/interface.go

@@ -0,0 +1,19 @@
+package decompress
+
+import (
+	"errors"
+	"io"
+)
+
+var ErrNotResetable = errors.New("decompressor not resetable")
+
+type Decompressor interface {
+	//Creates a new decompressor reading from src.
+	Reader(src io.Reader) (io.ReadCloser, error)
+	//Reports whether Reset will work or not.
+	Resetable() bool
+	//Reset attempts to re-use an old decompressor with new data.
+	//Will return ErrNotResetable if not Resetable().
+	//Must ALWAYS be provided with a reader created with Reader.
+	Reset(old, src io.Reader) error
+}

internal/decompress/lz4.go

@@ -0,0 +1,20 @@
+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
+}
+
+func (l Lz4) Resetable() bool { return true }
+
+func (l Lz4) Reset(old, src io.Reader) error {
+	old.(*lz4.Reader).Reset(src)
+	return nil
+}

internal/decompress/lzma.go

@@ -0,0 +1,18 @@
+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
+}
+
+func (l Lzma) Resetable() bool { return false }
+
+func (l Lzma) Reset(old, src io.Reader) error { return ErrNotResetable }

internal/decompress/lzo.go

@@ -0,0 +1,22 @@
+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
+}
+
+func (l Lzo) Resetable() bool { return false }
+
+func (l Lzo) Reset(old, src io.Reader) error { return ErrNotResetable }

internal/decompress/xz.go

@@ -0,0 +1,20 @@
+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
+}
+
+func (x Xz) Resetable() bool { return true }
+
+func (x Xz) Reset(old, src io.Reader) error {
+	return old.(*xz.Reader).Reset(src)
+}

internal/decompress/zstd.go

@@ -0,0 +1,29 @@
+package decompress
+
+import (
+	"io"
+
+	"github.com/klauspost/compress/zstd"
+)
+
+type Zstd struct {
+	writeToReader *zstd.Decoder
+}
+
+func (z Zstd) Reader(src io.Reader) (io.ReadCloser, error) {
+	r, err := zstd.NewReader(src)
+	return r.IOReadCloser(), err
+}
+
+func (z Zstd) Resetable() bool { return true }
+
+func (z Zstd) Reset(old, src io.Reader) error {
+	return old.(*zstd.Decoder).Reset(src)
+}
+
+func (z *Zstd) Decode(in []byte) (out []byte, err error) {
+	if z.writeToReader == nil {
+		z.writeToReader, _ = zstd.NewReader(nil)
+	}
+	return z.writeToReader.DecodeAll(in, nil)
+}

internal/directory/directory.go

@@ -6,89 +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 {
-	*Header
-	Name string
-	EntryRaw
+	Name       string
+	BlockStart uint32
+	Type       uint16
+	Offset     uint16
 }
 
-//NewEntry creates a new directory entry
-func NewEntry(rdr io.Reader) (Entry, error) {
-	var entry Entry
-	err := binary.Read(rdr, binary.LittleEndian, &entry.EntryRaw)
+func readEntry(r io.Reader) (e entry, err error) {
+	err = binary.Read(r, binary.LittleEndian, &e.entryInit)
 	if err != nil {
-		return Entry{}, err
+		return
 	}
-	tmp := make([]byte, entry.EntryRaw.NameSize+1)
-	err = binary.Read(rdr, binary.LittleEndian, &tmp)
-	if err != nil {
-		return Entry{}, err
-	}
-	entry.Name = string(tmp)
-	return entry, err
+	e.Name = make([]byte, e.NameSize+1)
+	err = binary.Read(r, binary.LittleEndian, &e.Name)
+	return
 }
 
-//Directory is an entry in the directory table of a squashfs.
-//Will only have multiple headers if there are more then 256 entries
-type Directory struct {
-	Headers []Header
-	Entries []Entry
-}
-
-//NewDirectory reads the directory from rdr
-func NewDirectory(base io.Reader, size uint32) (*Directory, error) {
-	var dir Directory
-	var err error
-	tmp := make([]byte, size)
-	base.Read(tmp)
-	rdr := bytes.NewBuffer(tmp)
+func ReadEntries(rdr io.Reader, size uint32) (e []Entry, err error) {
+	dat := make([]byte, size-3)
+	rdr.Read(dat)
+	r := bytes.NewReader(dat)
+	var h header
+	var en entry
 	for {
-		var hdr Header
-		err = binary.Read(rdr, binary.LittleEndian, &hdr)
-		if err == io.ErrUnexpectedEOF {
-			break
+		err = binary.Read(r, binary.LittleEndian, &h)
+		if err == io.EOF {
+			err = nil
+			return
 		} else if err != nil {
-			return nil, err
+			return
 		}
-		hdr.Count++
-		headers := hdr.Count / 256
-		if hdr.Count%256 > 0 {
-			headers++
-		}
-		dir.Headers = append(dir.Headers, hdr)
-		for i := uint32(0); i < hdr.Count; i++ {
+		h.Entries++
+		for i := 0; i < int(h.Entries); i++ {
 			if i != 0 && i%256 == 0 {
-				var newHdr Header
-				err = binary.Read(rdr, binary.LittleEndian, &newHdr)
+				err = binary.Read(r, binary.LittleEndian, &h)
 				if err != nil {
-					return nil, err
+					return
 				}
-				dir.Headers = append(dir.Headers, newHdr)
 			}
-			var ent Entry
-			ent, err = NewEntry(rdr)
+			en, err = readEntry(r)
 			if err != nil {
-				return nil, err
+				return
 			}
-			ent.Header = &dir.Headers[len(dir.Headers)-1]
-			dir.Entries = append(dir.Entries, ent)
+			e = append(e, Entry{
+				Name:       string(en.Name),
+				BlockStart: h.InodeStart,
+				Type:       en.Type,
+				Offset:     en.Offset,
+			})
 		}
 	}
-	return &dir, nil
 }

internal/inode/dir.go

@@ -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
+}

internal/inode/file.go

@@ -0,0 +1,62 @@
+package inode
+
+import (
+	"encoding/binary"
+	"io"
+	"math"
+)
+
+type fileInit struct {
+	BlockStart uint32
+	FragInd    uint32
+	FragOffset uint32
+	Size       uint32
+}
+
+type File struct {
+	fileInit
+	BlockSizes []uint32
+}
+
+type eFileInit struct {
+	BlockStart uint64
+	Size       uint64
+	Sparse     uint64
+	LinkCount  uint32
+	FragInd    uint32
+	FragOffset 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
+	}
+	toRead := int(math.Floor(float64(f.Size) / float64(blockSize)))
+	if f.FragInd == 0xFFFFFFFF && f.Size%blockSize > 0 {
+		toRead++
+	}
+	f.BlockSizes = make([]uint32, toRead)
+	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
+	}
+	toRead := int(math.Floor(float64(f.Size) / float64(blockSize)))
+	if f.FragInd == 0xFFFFFFFF && f.Size%uint64(blockSize) > 0 {
+		toRead++
+	}
+	f.BlockSizes = make([]uint32, toRead)
+	err = binary.Read(r, binary.LittleEndian, &f.BlockSizes)
+	return
+}

internal/inode/inode.go

@@ -0,0 +1,79 @@
+package inode
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+	"strconv"
+)
+
+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 " + strconv.Itoa(int(i.Type)))
+	}
+	return
+}

internal/inode/inodetypes.go

@@ -1,256 +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
-	ExtSymlinkType
-	ExtBlockDeviceType
-	ExtCharDeviceType
-	ExtFifoType
-	ExtSocketType
-)
-
-//Header is the common header for all inodes
-type Header struct {
-	InodeType    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++ {
-		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     uint32
-	Size           uint32
-	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 / blockSize
-	if inode.Size%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
-}

internal/inode/misc.go

@@ -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
+}

internal/inode/process.go

@@ -1,125 +0,0 @@
-package inode
-
-import (
-	"encoding/binary"
-	"io"
-)
-
-//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 {
-	Info interface{} //Info is the parsed specific data. It's type is defined by Type.
-	Type int         //Type the inode type defined in the header. Here so it's easy to access
-	Header
-}
-
-//ProcessInode tries to read an inode from the BlockReader
-func ProcessInode(br io.Reader, blockSize uint32) (*Inode, error) {
-	var head Header
-	err := binary.Read(br, binary.LittleEndian, &head)
-	if err != nil {
-		return nil, err
-	}
-	var info interface{}
-	switch head.InodeType {
-	case DirType:
-		var inode Dir
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case FileType:
-		inode, err := NewFile(br, blockSize)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case SymType:
-		inode, err := NewSymlink(br)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case BlockDevType:
-		var inode Device
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case CharDevType:
-		var inode Device
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case FifoType:
-		var inode IPC
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case SocketType:
-		var inode IPC
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtDirType:
-		inode, err := NewExtendedDirectory(br)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtFileType:
-		inode, err := NewExtendedFile(br, blockSize)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtSymlinkType:
-		inode, err := NewExtendedSymlink(br)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtBlockDeviceType:
-		var inode ExtDevice
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtCharDeviceType:
-		var inode ExtDevice
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtFifoType:
-		var inode ExtIPC
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	case ExtSocketType:
-		var inode ExtIPC
-		err = binary.Read(br, binary.LittleEndian, &inode)
-		if err != nil {
-			return nil, err
-		}
-		info = inode
-	}
-	return &Inode{
-		Type:   int(head.InodeType),
-		Header: head,
-		Info:   info,
-	}, nil
-}

internal/inode/sym.go

@@ -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
+}

internal/metadata/reader.go

@@ -0,0 +1,81 @@
+package metadata
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/CalebQ42/squashfs/internal/decompress"
+)
+
+type Reader struct {
+	master io.Reader
+	cur    io.Reader
+	d      decompress.Decompressor
+	comRdr io.Reader
+}
+
+func NewReader(master io.Reader, d decompress.Decompressor) *Reader {
+	return &Reader{
+		master: master,
+		d:      d,
+	}
+}
+
+func realSize(siz uint16) uint16 {
+	return siz &^ 0x8000
+}
+
+func (r *Reader) advance() (err error) {
+	if !r.d.Resetable() {
+		if clr, ok := r.cur.(io.Closer); ok {
+			clr.Close()
+		}
+	}
+	var raw uint16
+	err = binary.Read(r.master, binary.LittleEndian, &raw)
+	if err != nil {
+		return
+	}
+	size := realSize(raw)
+	r.cur = io.LimitReader(r.master, int64(size))
+	if size == raw {
+		if r.d.Resetable() {
+			if r.comRdr == nil {
+				r.cur, err = r.d.Reader(r.cur)
+				if err != nil {
+					return
+				}
+			} else {
+				err = r.d.Reset(r.comRdr, r.cur)
+				r.cur = r.comRdr
+			}
+		} else {
+			r.cur, err = r.d.Reader(r.cur)
+		}
+	}
+	return
+}
+
+func (r *Reader) Read(p []byte) (n int, err error) {
+	if r.cur == nil {
+		err = r.advance()
+		if err != nil {
+			return
+		}
+	}
+	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 := 0; i < tmpN; i++ {
+			p[n+i] = tmp[i]
+		}
+		n += tmpN
+	}
+	return
+}

internal/toreader/reader.go

@@ -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
+}

internal/toreader/readerat.go

@@ -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
+}

metadata.go

@@ -1,188 +0,0 @@
-package squashfs
-
-import (
-	"bytes"
-	"encoding/binary"
-	"errors"
-	"io"
-)
-
-type metadata struct {
-	raw        uint16
-	size       uint16
-	compressed bool
-}
-
-//MetadataReader is a block reader for metadata. It will automatically read the next block, when it reaches the end of a block.
-type metadataReader struct {
-	s          *Reader
-	headers    []*metadata
-	data       []byte
-	offset     int64
-	readOffset int
-}
-
-//NewMetadataReader creates a new MetadataReader, beginning to read at the given offset. It will automatically cache the first block at the location.
-func (s *Reader) newMetadataReader(offset int64) (*metadataReader, error) {
-	var br metadataReader
-	br.s = s
-	br.offset = offset
-	err := br.parseMetadata()
-	if err != nil {
-		return nil, err
-	}
-	err = br.readNextDataBlock()
-	if err != nil {
-		return nil, err
-	}
-	return &br, nil
-}
-
-//NewMetadataReaderFromInodeRef creates a new MetadataReader with the offsets set by the given inode reference.
-func (s *Reader) newMetadataReaderFromInodeRef(ref uint64) (*metadataReader, error) {
-	offset, metaOffset := processInodeRef(ref)
-	br, err := s.newMetadataReader(int64(s.super.InodeTableStart + offset))
-	if err != nil {
-		return nil, err
-	}
-	_, err = br.Seek(int64(metaOffset), io.SeekStart)
-	if err != nil {
-		return nil, err
-	}
-	return br, nil
-}
-
-//ProcessInodeRef processes an inode reference and returns two values
-//
-//The first value is the inode table offset. AKA, it's where the metadata block of the inode STARTS relative to the inode table.
-//
-//The second value is the offset of the inode, INSIDE of the metadata.
-func processInodeRef(inodeRef uint64) (tableOffset uint64, metaOffset uint64) {
-	tableOffset = inodeRef >> 16
-	metaOffset = inodeRef &^ 0xFFFFFFFF0000
-	return
-}
-
-func (br *metadataReader) parseMetadata() error {
-	var raw uint16
-	err := binary.Read(io.NewSectionReader(br.s.r, br.offset, 2), binary.LittleEndian, &raw)
-	if err != nil {
-		return err
-	}
-	br.offset += 2
-	compressed := raw&0x8000 != 0x8000
-	size := raw &^ 0x8000
-	br.headers = append(br.headers, &metadata{
-		raw:        raw,
-		size:       size,
-		compressed: compressed,
-	})
-	return nil
-}
-
-func (br *metadataReader) readNextDataBlock() error {
-	meta := br.headers[len(br.headers)-1]
-	r := io.NewSectionReader(br.s.r, br.offset, int64(meta.size))
-	if meta.compressed {
-		byts, err := br.s.decompressor.Decompress(r)
-		if err != nil {
-			return err
-		}
-		br.offset += int64(meta.size)
-		br.data = append(br.data, byts...)
-		return nil
-	}
-	var buf bytes.Buffer
-	_, err := io.Copy(&buf, r)
-	if err != nil {
-		return err
-	}
-	br.offset += int64(meta.size)
-	br.data = append(br.data, buf.Bytes()...)
-	return nil
-}
-
-//Read reads bytes into the given byte slice. Returns the amount of data read.
-func (br *metadataReader) Read(p []byte) (int, error) {
-	if br.readOffset+len(p) <= len(br.data) {
-		for i := 0; i < len(p); i++ {
-			p[i] = br.data[br.readOffset+i]
-		}
-		br.readOffset += len(p)
-		return len(p), nil
-	}
-	read := 0
-	for read < len(p) {
-		err := br.parseMetadata()
-		if err != nil {
-			br.readOffset += read
-			return read, err
-		}
-		err = br.readNextDataBlock()
-		if err != nil {
-			br.readOffset += read
-			return read, err
-		}
-		for ; read < len(p); read++ {
-			if br.readOffset+read < len(br.data) {
-				p[read] = br.data[br.readOffset+read]
-			} else {
-				break
-			}
-		}
-	}
-	br.readOffset += read
-	if read != len(p) {
-		return read, errors.New("Didn't read enough data")
-	}
-	return read, nil
-}
-
-//Seek will seek to the specified location (if possible). Seeking is relative to the uncompressed data.
-//When io.SeekCurrent or io.SeekStart is set, if seeking would put the offset beyond the current cached data, it will try to read the next data blocks to accomodate. On a failure it will seek to the end of the data.
-//When io.SeekEnd is set, it wil seek reletive to the currently cached data.
-func (br *metadataReader) Seek(offset int64, whence int) (int64, error) {
-	switch whence {
-	case io.SeekCurrent:
-		br.readOffset += int(offset)
-		for {
-			if br.readOffset < len(br.data) {
-				break
-			}
-			err := br.parseMetadata()
-			if err != nil {
-				br.readOffset = len(br.data)
-				return int64(br.readOffset), err
-			}
-			err = br.readNextDataBlock()
-			if err != nil {
-				br.readOffset = len(br.data)
-				return int64(br.readOffset), err
-			}
-		}
-	case io.SeekStart:
-		br.readOffset = int(offset)
-		for {
-			if br.readOffset < len(br.data) {
-				break
-			}
-			err := br.parseMetadata()
-			if err != nil {
-				br.readOffset = len(br.data)
-				return int64(br.readOffset), err
-			}
-			err = br.readNextDataBlock()
-			if err != nil {
-				br.readOffset = len(br.data)
-				return int64(br.readOffset), err
-			}
-		}
-	case io.SeekEnd:
-		br.readOffset = len(br.data) - int(offset)
-		if br.readOffset < 0 {
-			br.readOffset = 0
-			return int64(br.readOffset), errors.New("Trying to seek to a negative value")
-		}
-	}
-	return int64(br.readOffset), nil
-}

reader.go

@@ -7,248 +7,218 @@ import (
 	"math"
 	"time"
 
-	"github.com/CalebQ42/squashfs/internal/compression"
+	"github.com/CalebQ42/squashfs/internal/decompress"
+	"github.com/CalebQ42/squashfs/internal/directory"
 	"github.com/CalebQ42/squashfs/internal/inode"
+	"github.com/CalebQ42/squashfs/internal/metadata"
+	"github.com/CalebQ42/squashfs/internal/toreader"
 )
 
-const (
-	magic = 0x73717368
-)
+type Reader struct {
+	*FS
+	d           decompress.Decompressor
+	r           io.ReaderAt
+	fragEntries []fragEntry
+	ids         []uint32
+	// exportTable []uint64
+	s superblock
+}
 
 var (
-	//ErrNoMagic is returned if the magic number in the superblock isn't correct.
-	errNoMagic = errors.New("Magic number doesn't match. Either isn't a squashfs or corrupted")
-	//ErrIncompatibleCompression is returned if the compression type in the superblock doesn't work.
-	errIncompatibleCompression = errors.New("Compression type unsupported")
-	//ErrCompressorOptions is returned if compressor options is present. It's not currently supported.
-	errCompressorOptions = errors.New("Compressor options is not currently supported")
-	//ErrOptions is returned when compression options that I haven't tested is set. When this is returned, the Reader is also returned.
-	ErrOptions = errors.New("Possibly incompatible compressor options")
+	ErrorMagic   = errors.New("magic incorrect. probably not reading squashfs archive")
+	ErrorLog     = errors.New("block log is incorrect. possible corrupted archive")
+	ErrorVersion = errors.New("squashfs version of archive is not 4.0")
 )
 
-//Reader processes and reads a squashfs archive.
-type Reader struct {
-	r            io.ReaderAt
-	decompressor compression.Decompressor
-	fragOffsets  []uint64
-	idTable      []uint32
-	super        superblock
-	flags        superblockFlags
-}
+// The types of compression supported by squashfs
+const (
+	GZipCompression = uint16(iota + 1)
+	LZMACompression
+	LZOCompression
+	XZCompression
+	LZ4Compression
+	ZSTDCompression
+)
 
-//NewSquashfsReader returns a new squashfs.Reader from an io.ReaderAt
-func NewSquashfsReader(r io.ReaderAt) (*Reader, error) {
-	hasUnsupportedOptions := false
-	var rdr Reader
-	rdr.r = r
-	err := binary.Read(io.NewSectionReader(rdr.r, 0, int64(binary.Size(rdr.super))), binary.LittleEndian, &rdr.super)
+// Creates a new squashfs.Reader from the given io.Reader. NOTE: All data from the io.Reader will be read and stored in memory.
+func NewReaderFromReader(r io.Reader) (*Reader, error) {
+	rdr, err := toreader.NewReaderAt(r)
 	if err != nil {
 		return nil, err
 	}
-	if rdr.super.Magic != magic {
-		return nil, errNoMagic
+	return NewReader(rdr)
+}
+
+// Creates a new squashfs.Reader from the given io.ReaderAt.
+func NewReader(r io.ReaderAt) (*Reader, error) {
+	var squash Reader
+	squash.r = r
+	err := binary.Read(toreader.NewReader(r, 0), binary.LittleEndian, &squash.s)
+	if err != nil {
+		return nil, err
 	}
-	// if rdr.super.BlockLog == uint16(math.Log2(float64(rdr.super.BlockSize))) {
-	// 	return nil, errors.New("BlockSize and BlockLog doesn't match. The archive is probably corrupt")
-	// }
-	rdr.flags = rdr.super.GetFlags()
-	if rdr.flags.CompressorOptions {
-		switch rdr.super.CompressionType {
-		case GzipCompression:
-			gzip, err := compression.NewGzipCompressorWithOptions(io.NewSectionReader(rdr.r, int64(binary.Size(rdr.super)), 8))
-			if err != nil {
-				return nil, err
-			}
-			if gzip.HasCustomWindow || gzip.HasStrategies {
-				hasUnsupportedOptions = true
-			}
-			rdr.decompressor = gzip
-		case XzCompression:
-			xz, err := compression.NewXzCompressorWithOptions(io.NewSectionReader(rdr.r, int64(binary.Size(rdr.super)), 8))
-			if err != nil {
-				return nil, err
-			}
-			if xz.HasFilters {
-				return nil, errors.New("XZ compression options has filters. These are not yet supported")
-			}
-			rdr.decompressor = xz
-		case Lz4Compression:
-			lz4, err := compression.NewLz4CompressorWithOptions(io.NewSectionReader(rdr.r, int64(binary.Size(rdr.super)), 8))
-			if err != nil {
-				return nil, err
-			}
-			rdr.decompressor = lz4
-		case ZstdCompression:
-			zstd, err := compression.NewZstdCompressorWithOptions(io.NewSectionReader(rdr.r, int64(binary.Size(rdr.super)), 4))
-			if err != nil {
-				return nil, err
-			}
-			rdr.decompressor = zstd
-		default:
-			return nil, errIncompatibleCompression
-		}
-	} else {
-		switch rdr.super.CompressionType {
-		case GzipCompression:
-			rdr.decompressor = &compression.Gzip{}
-		case LzmaCompression:
-			rdr.decompressor = &compression.Lzma{}
-		case XzCompression:
-			rdr.decompressor = &compression.Xz{}
-		case Lz4Compression:
-			rdr.decompressor = &compression.Lz4{}
-		case ZstdCompression:
-			rdr.decompressor = &compression.Zstd{}
-		default:
-			//TODO: all compression types.
-			return nil, errIncompatibleCompression
-		}
+	if !squash.s.checkMagic() {
+		return nil, ErrorMagic
 	}
-	fragBlocks := int(math.Ceil(float64(rdr.super.FragCount) / 512))
-	if fragBlocks > 0 {
-		offset := int64(rdr.super.FragTableStart)
-		for i := 0; i < fragBlocks; i++ {
-			tmp := make([]byte, 8)
-			_, err = r.ReadAt(tmp, offset)
-			if err != nil {
-				return nil, err
-			}
-			rdr.fragOffsets = append(rdr.fragOffsets, binary.LittleEndian.Uint64(tmp))
-			offset += 8
-		}
+	if !squash.s.checkBlockLog() {
+		return nil, ErrorLog
 	}
-	unread := rdr.super.IDCount
-	blockOffsets := make([]uint64, int(math.Ceil(float64(rdr.super.IDCount)/2048)))
-	for i := range blockOffsets {
-		secRdr := io.NewSectionReader(r, int64(rdr.super.IDTableStart)+(8*int64(i)), 8)
-		err = binary.Read(secRdr, binary.LittleEndian, &blockOffsets[i])
+	if !squash.s.checkVersion() {
+		return nil, ErrorVersion
+	}
+	switch squash.s.CompType {
+	case GZipCompression:
+		squash.d = decompress.GZip{}
+	case LZMACompression:
+		squash.d = decompress.Lzma{}
+	case LZOCompression:
+		squash.d = decompress.Lzo{}
+	case XZCompression:
+		squash.d = decompress.Xz{}
+	case LZ4Compression:
+		squash.d = decompress.Lz4{}
+	case ZSTDCompression:
+		squash.d = &decompress.Zstd{}
+	default:
+		return nil, errors.New("uh, I need to do this, OR something if very wrong")
+	}
+	if !squash.s.noFragments() && squash.s.FragCount > 0 {
+		fragOffsets := make([]uint64, int(math.Ceil(float64(squash.s.FragCount)/512)))
+		err = binary.Read(toreader.NewReader(r, int64(squash.s.FragTableStart)), binary.LittleEndian, &fragOffsets)
 		if err != nil {
 			return nil, err
 		}
-		idRdr, err := rdr.newMetadataReader(int64(blockOffsets[i]))
-		if err != nil {
-			return nil, err
-		}
-		read := uint16(math.Min(float64(unread), 2048))
-		for i := uint16(0); i < read; i++ {
-			var tmp uint32
-			err = binary.Read(idRdr, binary.LittleEndian, &tmp)
+		squash.fragEntries = make([]fragEntry, squash.s.FragCount)
+		if len(fragOffsets) == 1 {
+			rdr := metadata.NewReader(toreader.NewReader(r, int64(fragOffsets[0])), squash.d)
+			err = binary.Read(rdr, binary.LittleEndian, &squash.fragEntries)
 			if err != nil {
 				return nil, err
 			}
-			rdr.idTable = append(rdr.idTable, tmp)
-		}
-		unread -= read
-	}
-	if hasUnsupportedOptions {
-		return &rdr, ErrOptions
-	}
-	return &rdr, nil
-}
-
-//ModTime is the last time the file was modified/created.
-func (r *Reader) ModTime() time.Time {
-	return time.Unix(int64(r.super.CreationTime), 0)
-}
-
-//ExtractTo tries to extract ALL files to the given path. This is the same as getting the root folder and extracting that.
-func (r *Reader) ExtractTo(path string) []error {
-	root, err := r.GetRootFolder()
-	if err != nil {
-		return []error{err}
-	}
-	return root.ExtractTo(path)
-}
-
-//GetRootFolder returns a squashfs.File that references the root directory of the squashfs archive.
-func (r *Reader) GetRootFolder() (root *File, err error) {
-	root = new(File)
-	mr, err := r.newMetadataReaderFromInodeRef(r.super.RootInodeRef)
-	if err != nil {
-		return nil, err
-	}
-	root.in, err = inode.ProcessInode(mr, r.super.BlockSize)
-	if err != nil {
-		return nil, err
-	}
-	root.path = "/"
-	root.filType = root.in.Type
-	root.r = r
-	return root, nil
-}
-
-//GetAllFiles returns a slice of ALL files and folders contained in the squashfs.
-func (r *Reader) GetAllFiles() (fils []*File, err error) {
-	root, err := r.GetRootFolder()
-	if err != nil {
-		return nil, err
-	}
-	return root.GetChildrenRecursively()
-}
-
-//FindFile returns the first file (in the same order as Reader.GetAllFiles) that the given function returns true for. Returns nil if nothing is found.
-func (r *Reader) FindFile(query func(*File) bool) *File {
-	root, err := r.GetRootFolder()
-	if err != nil {
-		return nil
-	}
-	fils, err := root.GetChildren()
-	if err != nil {
-		return nil
-	}
-	var childrenDirs []*File
-	for _, fil := range fils {
-		if query(fil) {
-			return fil
-		}
-		if fil.IsDir() {
-			childrenDirs = append(childrenDirs, fil)
+		} else {
+			toRead := squash.s.FragCount
+			var curRead uint32
+			var tmp []fragEntry
+			var rdr *metadata.Reader
+			var offset int
+			for i := range fragOffsets {
+				curRead = uint32(math.Min(512, float64(toRead)))
+				tmp = make([]fragEntry, curRead)
+				rdr = metadata.NewReader(toreader.NewReader(r, int64(fragOffsets[i])), squash.d)
+				err = binary.Read(rdr, binary.LittleEndian, &tmp)
+				if err != nil {
+					return nil, err
+				}
+				offset = int(squash.s.FragCount - toRead)
+				for i := range tmp {
+					squash.fragEntries[offset+i] = tmp[i]
+				}
+				toRead -= curRead
+			}
 		}
 	}
-	for len(childrenDirs) != 0 {
-		var tmp []*File
-		for _, dirs := range childrenDirs {
-			chil, err := dirs.GetChildren()
+	if squash.s.IdCount > 0 {
+		idOffsets := make([]uint64, int(math.Ceil(float64(squash.s.IdCount)/2048)))
+		err = binary.Read(toreader.NewReader(r, int64(squash.s.IdTableStart)), binary.LittleEndian, &idOffsets)
+		if err != nil {
+			return nil, err
+		}
+		squash.ids = make([]uint32, squash.s.IdCount)
+		if len(idOffsets) == 1 {
+			rdr := metadata.NewReader(toreader.NewReader(r, int64(idOffsets[0])), squash.d)
+			err = binary.Read(rdr, binary.LittleEndian, &squash.ids)
 			if err != nil {
-				return nil
+				return nil, err
 			}
-			for _, child := range chil {
-				if query(child) {
-					return child
+		} else {
+			toRead := squash.s.IdCount
+			var curRead uint16
+			var tmp []uint32
+			var rdr *metadata.Reader
+			var offset int
+			for i := range idOffsets {
+				curRead = uint16(math.Min(2048, float64(toRead)))
+				tmp = make([]uint32, curRead)
+				rdr = metadata.NewReader(toreader.NewReader(r, int64(idOffsets[i])), squash.d)
+				err = binary.Read(rdr, binary.LittleEndian, &tmp)
+				if err != nil {
+					return nil, err
 				}
-				if child.IsDir() {
-					tmp = append(tmp, child)
+				offset = int(squash.s.IdCount - toRead)
+				for i := range tmp {
+					squash.ids[offset+i] = tmp[i]
 				}
+				toRead -= curRead
 			}
 		}
-		childrenDirs = tmp
 	}
-	return nil
+	root, err := squash.inodeFromRef(squash.s.RootInodeRef)
+	if err != nil {
+		return nil, err
+	}
+	rootEnts, err := squash.readDirectory(root)
+	if err != nil {
+		return nil, err
+	}
+	enType := root.Type
+	if enType == inode.EDir {
+		enType = inode.Dir
+	}
+	squash.FS = &FS{
+		e: rootEnts,
+		File: &File{
+			rdr: &squash,
+			i:   root,
+			e: directory.Entry{
+				Name: "",
+				Type: enType,
+			},
+			r: &squash,
+		},
+	}
+	return &squash, nil
 }
 
-//FindAll returns all files where the given function returns true.
-func (r *Reader) FindAll(query func(*File) bool) (all []*File) {
-	root, err := r.GetRootFolder()
-	if err != nil {
-		return nil
-	}
-	fils, err := root.GetChildrenRecursively()
-	if err != nil {
-		return nil
-	}
-	for _, fil := range fils {
-		if query(fil) {
-			all = append(all, fil)
-		}
-	}
-	return
-}
+// func (r *Reader) initExport() (err error) {
+// 	num := int(math.Ceil(float64(r.s.InodeCount) / 1024))
+// 	offsets := make([]uint64, num)
+// 	err = binary.Read(toreader.NewReader(r.r, int64(r.s.ExportTableStart)), binary.LittleEndian, &offsets)
+// 	if err != nil {
+// 		return
+// 	}
+// 	left := r.s.InodeCount
+// 	var toRead uint32
+// 	var new []uint64
+// 	var rdr *metadata.Reader
+// 	for i := range offsets {
+// 		rdr = metadata.NewReader(toreader.NewReader(r.r, int64(offsets[i])), r.d)
+// 		toRead = uint32(math.Min(1024, float64(left)))
+// 		new = make([]uint64, toRead)
+// 		err = binary.Read(rdr, binary.LittleEndian, &new)
+// 		if err != nil {
+// 			return
+// 		}
+// 		left -= toRead
+// 		r.exportTable = append(r.exportTable, new...)
+// 	}
+// 	return nil
+// }
 
-//GetFileAtPath will return the file at the given path. If the file cannot be found, will return nil.
-func (r *Reader) GetFileAtPath(path string) *File {
-	dir, err := r.GetRootFolder()
-	if err != nil {
-		return nil
-	}
-	return dir.GetFileAtPath(path)
+// func (r *Reader) inode(index uint32) (i inode.Inode, err error) {
+// 	if r.s.exportable() {
+// 		if r.exportTable == nil {
+// 			err = r.initExport()
+// 			if err != nil {
+// 				return
+// 			}
+// 		}
+// 		return r.inodeFromRef(r.exportTable[index-1])
+// 	}
+// 	err = errors.New("archive is not exportable")
+// 	return
+// }
+
+// Returns the last time the archive was modified.
+func (r Reader) ModTime() time.Time {
+	return time.Unix(int64(r.s.ModTime), 0)
 }

reader_file.go

@@ -0,0 +1,351 @@
+package squashfs
+
+import (
+	"errors"
+	"io"
+	"io/fs"
+	"log"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"github.com/CalebQ42/squashfs/internal/directory"
+	"github.com/CalebQ42/squashfs/internal/inode"
+)
+
+// File represents a file inside a squashfs archive.
+type File struct {
+	i        inode.Inode
+	rdr      io.Reader
+	fullRdr  io.WriterTo
+	r        *Reader
+	parent   *FS
+	e        directory.Entry
+	dirsRead int
+}
+
+var (
+	ErrReadNotFile = errors.New("read called on non-file")
+)
+
+func (r Reader) newFile(en directory.Entry, parent *FS) (*File, error) {
+	i, err := r.inodeFromDir(en)
+	if err != nil {
+		return nil, err
+	}
+	var rdr io.Reader
+	var full io.WriterTo
+	if i.Type == inode.Fil || i.Type == inode.EFil {
+		full, rdr, err = r.getReaders(i)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return &File{
+		e:       en,
+		i:       i,
+		rdr:     rdr,
+		fullRdr: full,
+		r:       &r,
+		parent:  parent,
+	}, nil
+}
+
+// Stat returns the File's fs.FileInfo
+func (f File) Stat() (fs.FileInfo, error) {
+	return newFileInfo(f.e, f.i), nil
+}
+
+// Read reads the data from the file. Only works if file is a normal file.
+func (f File) Read(p []byte) (int, error) {
+	if f.i.Type != inode.Fil && f.i.Type != inode.EFil {
+		return 0, ErrReadNotFile
+	}
+	if f.rdr == nil {
+		return 0, fs.ErrClosed
+	}
+	return f.rdr.Read(p)
+}
+
+// WriteTo writes all data from the file to the writer. This is multi-threaded.
+// The underlying reader is seperate from the one used with Read and can be reused.
+func (f File) WriteTo(w io.Writer) (int64, error) {
+	return f.fullRdr.WriteTo(w)
+}
+
+// Close simply nils the underlying reader. Here mostly to satisfy fs.File
+func (f *File) Close() error {
+	f.rdr = nil
+	return nil
+}
+
+// ReadDir returns n fs.DirEntry's that's contained in the File (if it's a directory).
+// If n <= 0 all fs.DirEntry's are returned.
+func (f *File) ReadDir(n int) (out []fs.DirEntry, err error) {
+	if !f.IsDir() {
+		return nil, errors.New("File is not a directory")
+	}
+	ents, err := f.r.readDirectory(f.i)
+	if err != nil {
+		return nil, err
+	}
+	start, end := 0, len(ents)
+	if n > 0 {
+		start, end = f.dirsRead, f.dirsRead+n
+		if end > len(f.r.e) {
+			end = len(f.r.e)
+			err = io.EOF
+		}
+	}
+	var fi fileInfo
+	for _, e := range ents[start:end] {
+		fi, err = f.r.newFileInfo(e)
+		if err != nil {
+			f.dirsRead += len(out)
+			return
+		}
+		out = append(out, fs.FileInfoToDirEntry(fi))
+	}
+	f.dirsRead += len(out)
+	return
+}
+
+// FS returns the File as a FS.
+func (f *File) FS() (*FS, error) {
+	if !f.IsDir() {
+		return nil, errors.New("File is not a directory")
+	}
+	ents, err := f.r.readDirectory(f.i)
+	if err != nil {
+		return nil, err
+	}
+	return &FS{
+		File: f,
+		e:    ents,
+	}, nil
+}
+
+// IsDir Yep.
+func (f File) IsDir() bool {
+	return f.i.Type == inode.Dir || f.i.Type == inode.EDir
+}
+
+// IsRegular yep.
+func (f File) IsRegular() bool {
+	return f.i.Type == inode.Fil || f.i.Type == inode.EFil
+}
+
+// IsSymlink yep.
+func (f File) IsSymlink() bool {
+	return f.i.Type == inode.Sym || f.i.Type == inode.ESym
+}
+
+// SymlinkPath returns the symlink's target path. Is the File isn't a symlink, returns an empty string.
+func (f File) SymlinkPath() string {
+	switch f.i.Type {
+	case inode.Sym:
+		return string(f.i.Data.(inode.Symlink).Target)
+	case inode.ESym:
+		return string(f.i.Data.(inode.ESymlink).Target)
+	}
+	return ""
+}
+
+func (f File) path() string {
+	if f.parent == nil {
+		return f.e.Name
+	}
+	return f.parent.path() + "/" + f.e.Name
+}
+
+// GetSymlinkFile returns the File the symlink is pointing to.
+// If not a symlink, or the target is unobtainable (such as it being outside the archive or it's absolute) returns nil
+func (f File) GetSymlinkFile() *File {
+	if !f.IsSymlink() {
+		return nil
+	}
+	if strings.HasPrefix(f.SymlinkPath(), "/") {
+		return nil
+	}
+	sym, err := f.parent.Open(f.SymlinkPath())
+	if err != nil {
+		return nil
+	}
+	return sym.(*File)
+}
+
+// ExtractionOptions are available options on how to extract.
+type ExtractionOptions struct {
+	LogOutput          io.Writer   //Where error log should write. If nil, uses os.Stdout. Has no effect if verbose is false.
+	DereferenceSymlink bool        //Replace symlinks with the target file
+	UnbreakSymlink     bool        //Try to make sure symlinks remain unbroken when extracted, without changing the symlink
+	Verbose            bool        //Prints extra info to log on an error
+	FolderPerm         fs.FileMode //The permissions used when creating the extraction folder
+}
+
+// DefaultOptions is the default ExtractionOptions.
+func DefaultOptions() ExtractionOptions {
+	return ExtractionOptions{
+		FolderPerm: 0755,
+	}
+}
+
+// ExtractTo extracts the File to the given folder with the default options.
+// If the File is a directory, it instead extracts the directory's contents to the folder.
+func (f File) ExtractTo(folder string) error {
+	return f.ExtractWithOptions(folder, DefaultOptions())
+}
+
+// ExtractSymlink extracts the File to the folder with the DereferenceSymlink option.
+// If the File is a directory, it instead extracts the directory's contents to the folder.
+func (f File) ExtractSymlink(folder string) error {
+	return f.ExtractWithOptions(folder, ExtractionOptions{
+		DereferenceSymlink: true,
+		FolderPerm:         0755,
+	})
+}
+
+// ExtractWithOptions extracts the File to the given folder with the given ExtrationOptions.
+// If the File is a directory, it instead extracts the directory's contents to the folder.
+func (f File) ExtractWithOptions(folder string, op ExtractionOptions) error {
+	if op.Verbose {
+		if op.LogOutput == nil {
+			op.LogOutput = os.Stdout
+		}
+		log.SetOutput(op.LogOutput)
+	}
+	return f.realExtract(folder, op)
+}
+
+func (f File) realExtract(folder string, op ExtractionOptions) error {
+	err := os.MkdirAll(folder, op.FolderPerm)
+	folder = filepath.Clean(folder)
+	if err != nil && !os.IsExist(err) {
+		if op.Verbose {
+			log.Println("Error while creating extraction folder")
+		}
+		return err
+	}
+	if f.IsDir() {
+		filFS, _ := f.FS()
+		var ents []directory.Entry
+		ents, err = f.r.readDirectory(f.i)
+		if err != nil {
+			if op.Verbose {
+				log.Println("Error while reading children of", f.path())
+			}
+			return err
+		}
+		errChan := make(chan error)
+		for i := 0; i < len(ents); i++ {
+			go func(ent directory.Entry) {
+				fil, goErr := f.r.newFile(ent, filFS)
+				if goErr != nil {
+					if op.Verbose {
+						log.Println("Error while reading info for", filepath.Join(f.path(), ent.Name))
+					}
+					errChan <- goErr
+					return
+				}
+				if fil.IsDir() {
+					info, _ := fil.Stat()
+					err = os.Mkdir(filepath.Join(folder, fil.e.Name), info.Mode())
+					if err != nil {
+						if op.Verbose {
+							log.Println("Error while creating", filepath.Join(folder, fil.e.Name))
+						}
+						errChan <- err
+						return
+					}
+					errChan <- fil.realExtract(filepath.Join(folder, fil.e.Name), op)
+				} else {
+					errChan <- fil.realExtract(folder, op)
+				}
+				fil.Close()
+			}(ents[i])
+		}
+		for i := 0; i < len(ents); i++ {
+			err = <-errChan
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	} else if f.IsRegular() {
+		var fil *os.File
+		fil, err = os.Create(folder + "/" + f.e.Name)
+		if os.IsExist(err) {
+			os.Remove(folder + "/" + f.e.Name)
+			fil, err = os.Create(folder + "/" + f.e.Name)
+			if err != nil {
+				if op.Verbose {
+					log.Println("Error while creating", folder+"/"+f.e.Name)
+				}
+				return err
+			}
+		} else if err != nil {
+			if op.Verbose {
+				log.Println("Error while creating", folder+"/"+f.e.Name)
+			}
+			return err
+		}
+		_, err = io.Copy(fil, f)
+		if err != nil {
+			if op.Verbose {
+				log.Println("Error while copying data to", folder+"/"+f.e.Name)
+			}
+			return err
+		}
+		return nil
+	} else if f.IsSymlink() {
+		symPath := f.SymlinkPath()
+		if op.DereferenceSymlink {
+			fil := f.GetSymlinkFile()
+			if fil == nil {
+				if op.Verbose {
+					log.Println("Symlink path(", symPath, ") is unobtainable:", folder+"/"+f.e.Name)
+				}
+				return errors.New("cannot get symlink target")
+			}
+			fil.e.Name = f.e.Name
+			err = fil.realExtract(folder, op)
+			if err != nil {
+				if op.Verbose {
+					log.Println("Error while extracting the symlink's file:", folder+"/"+f.e.Name)
+				}
+				return err
+			}
+			return nil
+		} else if op.UnbreakSymlink {
+			fil := f.GetSymlinkFile()
+			if fil == nil {
+				if op.Verbose {
+					log.Println("Symlink path(", symPath, ") is unobtainable:", folder+"/"+f.e.Name)
+				}
+				return errors.New("cannot get symlink target")
+			}
+			extractLoc := filepath.Clean(folder + "/" + filepath.Dir(symPath))
+			err = fil.realExtract(extractLoc, op)
+			if err != nil {
+				if op.Verbose {
+					log.Println("Error while extracting ", folder+"/"+f.e.Name)
+				}
+				return err
+			}
+		}
+		err = os.Symlink(f.SymlinkPath(), folder+"/"+f.e.Name)
+		if os.IsExist(err) {
+			os.Remove(folder + "/" + f.e.Name)
+			err = os.Symlink(f.SymlinkPath(), folder+"/"+f.e.Name)
+		}
+		if err != nil {
+			if op.Verbose {
+				log.Println("Error while making symlink:", folder+"/"+f.e.Name)
+			}
+			return err
+		}
+		return nil
+	}
+	return errors.New("Unsupported file type. Inode type: " + strconv.Itoa(int(f.i.Type)))
+}

reader_fileinfo.go

@@ -0,0 +1,66 @@
+package squashfs
+
+import (
+	"io/fs"
+	"time"
+
+	"github.com/CalebQ42/squashfs/internal/directory"
+	"github.com/CalebQ42/squashfs/internal/inode"
+)
+
+type fileInfo struct {
+	e       directory.Entry
+	size    int64
+	perm    uint32
+	modTime uint32
+}
+
+func (r Reader) newFileInfo(e directory.Entry) (fileInfo, error) {
+	i, err := r.inodeFromDir(e)
+	if err != nil {
+		return fileInfo{}, err
+	}
+	return newFileInfo(e, i), nil
+}
+
+func newFileInfo(e directory.Entry, i inode.Inode) fileInfo {
+	var size int64
+	if i.Type == inode.Fil {
+		size = int64(i.Data.(inode.File).Size)
+	} else if i.Type == inode.EFil {
+		size = int64(i.Data.(inode.EFile).Size)
+	}
+	return fileInfo{
+		e:       e,
+		size:    size,
+		perm:    uint32(i.Perm),
+		modTime: i.ModTime,
+	}
+}
+
+func (f fileInfo) Name() string {
+	return f.e.Name
+}
+
+func (f fileInfo) Size() int64 {
+	return f.size
+}
+
+func (f fileInfo) Mode() fs.FileMode {
+	if f.IsDir() {
+		return fs.FileMode(f.perm | uint32(fs.ModeDir))
+	}
+	return fs.FileMode(f.perm)
+}
+
+func (f fileInfo) ModTime() time.Time {
+	return time.Unix(int64(f.modTime), 0)
+}
+
+func (f fileInfo) IsDir() bool {
+	return f.e.Type == inode.Dir
+}
+
+func (f fileInfo) Sys() any {
+	return nil
+}

reader_frag.go

@@ -0,0 +1,22 @@
+package squashfs
+
+import (
+	"io"
+
+	"github.com/CalebQ42/squashfs/internal/toreader"
+)
+
+type fragEntry struct {
+	Start uint64
+	Size  uint32
+	_     uint32
+}
+
+func (r Reader) fragReader(index uint32) (io.Reader, error) {
+	realSize := r.fragEntries[index].Size &^ (1 << 24)
+	rdr := io.LimitReader(toreader.NewReader(r.r, int64(r.fragEntries[index].Start)), int64(realSize))
+	if realSize != r.fragEntries[index].Size {
+		return rdr, nil
+	}
+	return r.d.Reader(rdr)
+}

reader_fs.go

@@ -0,0 +1,375 @@
+package squashfs
+
+import (
+	"bytes"
+	"io"
+	"io/fs"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/CalebQ42/squashfs/internal/directory"
+	"github.com/CalebQ42/squashfs/internal/inode"
+)
+
+// FS is a fs.FS representation of a squashfs directory.
+// Implements fs.GlobFS, fs.ReadDirFS, fs.ReadFileFS, fs.StatFS, and fs.SubFS
+type FS struct {
+	*File
+	e []directory.Entry
+}
+
+func (r Reader) newFS(e directory.Entry, parent *FS) (*FS, error) {
+	i, err := r.inodeFromDir(e)
+	if err != nil {
+		return nil, err
+	}
+	ents, err := r.readDirectory(i)
+	if err != nil {
+		return nil, err
+	}
+	return &FS{
+		File: &File{
+			i:      i,
+			r:      &r,
+			parent: parent,
+			e:      e,
+		},
+		e: ents,
+	}, nil
+}
+
+// Open opens the file at name. Returns a squashfs.File.
+func (f FS) Open(name string) (fs.File, error) {
+	name = filepath.Clean(name)
+	if !fs.ValidPath(name) {
+		return nil, &fs.PathError{
+			Op:   "open",
+			Path: name,
+			Err:  fs.ErrInvalid,
+		}
+	}
+	if name == "." || name == "" {
+		return f.File, nil
+	}
+	split := strings.Split(name, "/")
+	for i := range f.e {
+		if f.e[i].Name != split[0] {
+			continue
+		}
+		if len(split) > 1 && f.e[i].Type != inode.Dir {
+			return nil, &fs.PathError{
+				Op:   "open",
+				Path: name,
+				Err:  fs.ErrNotExist,
+			}
+		}
+		if len(split) > 1 {
+			newFS, err := f.r.newFS(f.e[i], &f)
+			if err != nil {
+				return nil, &fs.PathError{
+					Op:   "open",
+					Path: name,
+					Err:  err,
+				}
+			}
+			out, err := newFS.Open(strings.Join(split[1:], "/"))
+			if err != nil {
+				err.(*fs.PathError).Path = name
+			}
+			return out, err
+		}
+		out, err := f.r.newFile(f.e[i], &f)
+		if err != nil {
+			err = &fs.PathError{
+				Op:   "open",
+				Path: name,
+				Err:  err,
+			}
+		}
+		return out, err
+	}
+	return nil, &fs.PathError{
+		Op:   "open",
+		Path: name,
+		Err:  fs.ErrNotExist,
+	}
+}
+
+// Glob returns the name of the files at the given pattern.
+// All paths are relative to the FS.
+// Uses filepath.Match to compare names.
+func (f FS) Glob(pattern string) (out []string, err error) {
+	pattern = filepath.Clean(pattern)
+	if !fs.ValidPath(pattern) {
+		return nil, &fs.PathError{
+			Op:   "glob",
+			Path: pattern,
+			Err:  fs.ErrInvalid,
+		}
+	}
+	split := strings.Split(pattern, "/")
+	for i := 0; i < len(f.e); i++ {
+		if match, _ := path.Match(split[0], f.e[i].Name); match {
+			if len(split) == 1 {
+				out = append(out, f.e[i].Name)
+				continue
+			}
+			sub, err := f.Sub(split[0])
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "glob"
+					pathErr.Path = pattern
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "glob",
+					Path: pattern,
+					Err:  err,
+				}
+			}
+			subGlob, err := sub.(fs.GlobFS).Glob(strings.Join(split[1:], "/"))
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "glob"
+					pathErr.Path = pattern
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "glob",
+					Path: pattern,
+					Err:  err,
+				}
+			}
+			for i := 0; i < len(subGlob); i++ {
+				subGlob[i] = f.File.e.Name + "/" + subGlob[i]
+			}
+			out = append(out, subGlob...)
+		}
+	}
+	return
+}
+
+// ReadDir returns all the DirEntry returns all DirEntry's for the directory at name.
+// If name is not a directory, returns an error.
+func (f FS) ReadDir(name string) ([]fs.DirEntry, error) {
+	name = filepath.Clean(name)
+	if !fs.ValidPath(name) {
+		return nil, &fs.PathError{
+			Op:   "readdir",
+			Path: name,
+			Err:  fs.ErrInvalid,
+		}
+	}
+	if name == "." || name == "" {
+		return f.File.ReadDir(-1)
+	}
+	split := strings.Split(name, "/")
+	for i := 0; i < len(f.e); i++ {
+		if split[0] == f.e[i].Name {
+			if len(split) == 1 {
+				fi, err := f.r.newFile(f.e[i], &f)
+				if err != nil {
+					return nil, &fs.PathError{
+						Op:   "readdir",
+						Path: name,
+						Err:  err,
+					}
+				}
+				out, err := fi.ReadDir(-1)
+				if err != nil {
+					err = &fs.PathError{
+						Op:   "readdir",
+						Path: name,
+						Err:  err,
+					}
+				}
+				return out, err
+			}
+			sub, err := f.Sub(split[0])
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "readir"
+					pathErr.Path = name
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "readdir",
+					Path: name,
+					Err:  err,
+				}
+			}
+			redDir, err := sub.(fs.ReadDirFS).ReadDir(strings.Join(split[1:], "/"))
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "readdir"
+					pathErr.Path = name
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "readdir",
+					Path: name,
+					Err:  err,
+				}
+			}
+			return redDir, nil
+		}
+	}
+	return nil, &fs.PathError{
+		Op:   "readdir",
+		Path: name,
+		Err:  fs.ErrNotExist,
+	}
+}
+
+// ReadFile returns the data (in []byte) for the file at name.
+func (f FS) ReadFile(name string) ([]byte, error) {
+	fil, err := f.Open(name)
+	if err != nil {
+		if pathErr, ok := err.(*fs.PathError); ok {
+			pathErr.Op = "readfile"
+			pathErr.Path = name
+			return nil, pathErr
+		}
+	}
+	var buf bytes.Buffer
+	_, err = io.Copy(&buf, fil)
+	if err != nil {
+		return nil, &fs.PathError{
+			Op:   "readfile",
+			Path: name,
+			Err:  err,
+		}
+	}
+	return buf.Bytes(), nil
+}
+
+// Stat returns the fs.FileInfo for the file at name.
+func (f FS) Stat(name string) (fs.FileInfo, error) {
+	name = filepath.Clean(strings.TrimPrefix(name, "/"))
+	if !fs.ValidPath(name) {
+		return nil, &fs.PathError{
+			Op:   "stat",
+			Path: name,
+			Err:  fs.ErrInvalid,
+		}
+	}
+	if name == "." || name == "" {
+		return f.File.Stat()
+	}
+	split := strings.Split(name, "/")
+	for i := 0; i < len(f.e); i++ {
+		if split[0] == f.e[i].Name {
+			if len(split) == 1 {
+				in, err := f.r.newFileInfo(f.e[i])
+				if err != nil {
+					err = &fs.PathError{
+						Op:   "stat",
+						Path: name,
+						Err:  err,
+					}
+				}
+				return in, err
+			}
+			sub, err := f.Sub(split[0])
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "stat"
+					pathErr.Path = name
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "stat",
+					Path: name,
+					Err:  err,
+				}
+			}
+			stat, err := sub.(fs.StatFS).Stat(strings.Join(split[1:], "/"))
+			if err != nil {
+				if pathErr, ok := err.(*fs.PathError); ok {
+					if pathErr.Err == fs.ErrNotExist {
+						continue
+					}
+					pathErr.Op = "stat"
+					pathErr.Path = name
+					return nil, pathErr
+				}
+				return nil, &fs.PathError{
+					Op:   "stat",
+					Path: name,
+					Err:  err,
+				}
+			}
+			return stat, nil
+		}
+	}
+	return nil, &fs.PathError{
+		Op:   "stat",
+		Path: name,
+		Err:  fs.ErrNotExist,
+	}
+}
+
+// Sub returns the FS at dir
+func (f FS) Sub(dir string) (fs.FS, error) {
+	dir = filepath.Clean(dir)
+	if !fs.ValidPath(dir) {
+		return nil, &fs.PathError{
+			Op:   "sub",
+			Path: dir,
+			Err:  fs.ErrInvalid,
+		}
+	}
+	if dir == "." || dir == "" {
+		return f, nil
+	}
+	split := strings.Split(dir, "/")
+	for i := range f.e {
+		if f.e[i].Name != split[0] {
+			continue
+		}
+		if f.e[i].Type != inode.Dir {
+			return nil, &fs.PathError{
+				Op:   "sub",
+				Path: dir,
+				Err:  fs.ErrNotExist,
+			}
+		}
+		newFS, err := f.r.newFS(f.e[i], &f)
+		if err != nil {
+			return nil, &fs.PathError{
+				Op:   "sub",
+				Path: dir,
+				Err:  err,
+			}
+		}
+		if len(split) > 1 {
+			ret, err := newFS.Sub(strings.Join(split[1:], "/"))
+			if err != nil {
+				err.(*fs.PathError).Path = dir
+			}
+			return ret, err
+		}
+		return newFS, nil
+	}
+	return nil, &fs.PathError{
+		Op:   "sub",
+		Path: dir,
+		Err:  fs.ErrNotExist,
+	}
+}

reader_inode.go

@@ -0,0 +1,114 @@
+package squashfs
+
+import (
+	"errors"
+	"io"
+
+	"github.com/CalebQ42/squashfs/internal/data"
+	"github.com/CalebQ42/squashfs/internal/directory"
+	"github.com/CalebQ42/squashfs/internal/inode"
+	"github.com/CalebQ42/squashfs/internal/metadata"
+	"github.com/CalebQ42/squashfs/internal/toreader"
+)
+
+func (r Reader) inodeFromRef(ref uint64) (i inode.Inode, err error) {
+	offset, meta := (ref>>16)+r.s.InodeTableStart, ref&0xFFFF
+	rdr := metadata.NewReader(toreader.NewReader(r.r, int64(offset)), r.d)
+	_, err = rdr.Read(make([]byte, meta))
+	if err != nil {
+		return
+	}
+	return inode.Read(rdr, r.s.BlockSize)
+}
+
+func (r Reader) inodeFromDir(e directory.Entry) (i inode.Inode, err error) {
+	rdr := metadata.NewReader(toreader.NewReader(r.r, int64(uint64(e.BlockStart)+r.s.InodeTableStart)), r.d)
+	_, err = rdr.Read(make([]byte, e.Offset))
+	if err != nil {
+		return
+	}
+	return inode.Read(rdr, r.s.BlockSize)
+}
+
+func (r Reader) getReaders(i inode.Inode) (full *data.FullReader, rdr *data.Reader, err error) {
+	var fragOffset uint64
+	var blockOffset uint64
+	var blockSizes []uint32
+	var fragInd uint32
+	var fragSize uint32
+	if i.Type == inode.Fil {
+		fragOffset = uint64(i.Data.(inode.File).FragOffset)
+		blockOffset = uint64(i.Data.(inode.File).BlockStart)
+		blockSizes = i.Data.(inode.File).BlockSizes
+		fragInd = i.Data.(inode.File).FragInd
+		fragSize = i.Data.(inode.File).Size % r.s.BlockSize
+	} else if i.Type == inode.EFil {
+		fragOffset = uint64(i.Data.(inode.EFile).FragOffset)
+		blockOffset = i.Data.(inode.EFile).BlockStart
+		blockSizes = i.Data.(inode.EFile).BlockSizes
+		fragInd = i.Data.(inode.EFile).FragInd
+		fragSize = uint32(i.Data.(inode.EFile).Size % uint64(r.s.BlockSize))
+	} else {
+		return nil, nil, errors.New("getReaders called on non-file type")
+	}
+	rdr = data.NewReader(toreader.NewReader(r.r, int64(blockOffset)), r.d, blockSizes, r.s.BlockSize)
+	full = data.NewFullReader(r.r, uint64(blockOffset), r.d, blockSizes, r.s.BlockSize)
+	if fragInd != 0xFFFFFFFF {
+		full.AddFragment(func() (io.Reader, error) {
+			var fragRdr io.Reader
+			fragRdr, err = r.fragReader(fragInd)
+			if err != nil {
+				return nil, err
+			}
+			var n, tmpN int
+			for n != int(fragOffset) {
+				tmpN, err = fragRdr.Read(make([]byte, int(fragOffset)-n))
+				if err != nil {
+					return nil, err
+				}
+				n += tmpN
+			}
+			fragRdr = io.LimitReader(fragRdr, int64(fragSize))
+			return fragRdr, nil
+		})
+		var fragRdr io.Reader
+		fragRdr, err = r.fragReader(fragInd)
+		if err != nil {
+			return nil, nil, err
+		}
+		var n, tmpN int
+		for n != int(fragOffset) {
+			tmpN, err = fragRdr.Read(make([]byte, int(fragOffset)-n))
+			if err != nil {
+				return nil, nil, err
+			}
+			n += tmpN
+		}
+		fragRdr = io.LimitReader(fragRdr, int64(fragSize))
+		rdr.AddFragment(fragRdr)
+	}
+	return
+}
+
+func (r Reader) readDirectory(i inode.Inode) ([]directory.Entry, error) {
+	var offset uint64
+	var blockOffset uint16
+	var size uint32
+	if i.Type == inode.Dir {
+		offset = uint64(i.Data.(inode.Directory).BlockStart)
+		blockOffset = i.Data.(inode.Directory).Offset
+		size = uint32(i.Data.(inode.Directory).Size)
+	} else if i.Type == inode.EDir {
+		offset = uint64(i.Data.(inode.EDirectory).BlockStart)
+		blockOffset = i.Data.(inode.EDirectory).Offset
+		size = i.Data.(inode.EDirectory).Size
+	} else {
+		return nil, errors.New("readDirectory called on non-directory type")
+	}
+	rdr := metadata.NewReader(toreader.NewReader(r.r, int64(offset+r.s.DirTableStart)), r.d)
+	_, err := rdr.Read(make([]byte, blockOffset))
+	if err != nil {
+		return nil, err
+	}
+	return directory.ReadEntries(rdr, size)
+}

squash_test.go

@@ -1,232 +0,0 @@
-package squashfs
-
-import (
-	"fmt"
-	"io"
-	"net/http"
-	"os"
-	"os/exec"
-	"strconv"
-	"testing"
-	"time"
-
-	goappimage "github.com/CalebQ42/GoAppImage"
-)
-
-const (
-	downloadURL  = "https://github.com/srevinsaju/Firefox-Appimage/releases/download/firefox-v84.0.r20201221152838/firefox-84.0.r20201221152838-x86_64.AppImage"
-	appImageName = "firefox-84.0.r20201221152838-x86_64.AppImage"
-	squashfsName = "balenaEtcher-1.5.113-x64.AppImage.sfs" //testing with a ArchLinux root fs from the live img
-)
-
-func TestSquashfs(t *testing.T) {
-	wd, err := os.Getwd()
-	if err != nil {
-		t.Fatal(err)
-	}
-	squashFil, err := os.Open(wd + "/testing/" + squashfsName)
-	if err != nil {
-		t.Fatal(err)
-	}
-	rdr, err := NewSquashfsReader(squashFil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	fmt.Println("stuff", rdr.super.CompressionType)
-	fil := rdr.GetFileAtPath("*.desktop")
-	if fil == nil {
-		t.Fatal("Can't find desktop fil")
-	}
-	errs := fil.ExtractTo(wd + "/testing")
-	if len(errs) > 0 {
-		t.Fatal(errs)
-	}
-	errs = rdr.ExtractTo(wd + "/testing/" + squashfsName + ".d")
-	if len(errs) > 0 {
-		t.Fatal(errs)
-	}
-	t.Fatal("No Problems")
-}
-
-func TestAppImage(t *testing.T) {
-	t.Parallel()
-	wd, err := os.Getwd()
-	if err != nil {
-		t.Fatal(err)
-	}
-	aiFil, err := os.Open(wd + "/testing/" + appImageName)
-	if os.IsNotExist(err) {
-		err = downloadTestAppImage(wd + "/testing")
-		if err != nil {
-			t.Fatal(err)
-		}
-		aiFil, err = os.Open(wd + "/testing/" + appImageName)
-		if err != nil {
-			t.Fatal(err)
-		}
-	} else if err != nil {
-		t.Fatal(err)
-	}
-	defer aiFil.Close()
-	stat, _ := aiFil.Stat()
-	os.RemoveAll(wd + "/testing/firefox")
-	ai := goappimage.NewAppImage(wd + "/testing/" + appImageName)
-	start := time.Now()
-	rdr, err := NewSquashfsReader(io.NewSectionReader(aiFil, ai.Offset, stat.Size()-ai.Offset))
-	if err != nil {
-		t.Fatal(err)
-	}
-	errs := rdr.ExtractTo(wd + "/testing/firefox")
-	if len(errs) > 0 {
-		t.Fatal(errs)
-	}
-	// os.RemoveAll(wd + "/testing/" + appImageName + ".d")
-	// root, _ := rdr.GetRootFolder()
-	// errs := root.ExtractWithOptions(wd+"/testing/"+appImageName+".d", true, os.ModePerm, true)
-	// t.Fatal(errs)
-	fmt.Println(time.Since(start))
-	t.Fatal("No problemo!")
-}
-
-func TestUnsquashfs(t *testing.T) {
-	t.Parallel()
-	wd, err := os.Getwd()
-	if err != nil {
-		t.Fatal(err)
-	}
-	aiFil, err := os.Open(wd + "/testing/" + appImageName)
-	if os.IsNotExist(err) {
-		err = downloadTestAppImage(wd + "/testing")
-		if err != nil {
-			t.Fatal(err)
-		}
-		aiFil, err = os.Open(wd + "/testing/" + appImageName)
-		if err != nil {
-			t.Fatal(err)
-		}
-	} else if err != nil {
-		t.Fatal(err)
-	}
-	os.RemoveAll(wd + "/testing/unsquashFirefox")
-	os.RemoveAll(wd + "/testing/firefox")
-	ai := goappimage.NewAppImage(wd + "/testing/" + appImageName)
-	fmt.Println("Command:", "unsquashfs", "-d", wd+"/testing/unsquashFirefox", "-o", strconv.Itoa(int(ai.Offset)), aiFil.Name())
-	cmd := exec.Command("unsquashfs", "-d", wd+"/testing/unsquashFirefox", "-o", strconv.Itoa(int(ai.Offset)), aiFil.Name())
-	start := time.Now()
-	err = cmd.Run()
-	if err != nil {
-		t.Fatal(err)
-	}
-	fmt.Println(time.Since(start))
-	t.Fatal("HI")
-}
-
-func BenchmarkDragRace(b *testing.B) {
-	wd, err := os.Getwd()
-	if err != nil {
-		b.Fatal(err)
-	}
-	aiFil, err := os.Open(wd + "/testing/" + appImageName)
-	if os.IsNotExist(err) {
-		err = downloadTestAppImage(wd + "/testing")
-		if err != nil {
-			b.Fatal(err)
-		}
-		aiFil, err = os.Open(wd + "/testing/" + appImageName)
-		if err != nil {
-			b.Fatal(err)
-		}
-	} else if err != nil {
-		b.Fatal(err)
-	}
-	stat, _ := aiFil.Stat()
-	ai := goappimage.NewAppImage(wd + "/testing/" + appImageName)
-	os.RemoveAll(wd + "/testing/unsquashFirefox")
-	os.RemoveAll(wd + "/testing/firefox")
-	cmd := exec.Command("unsquashfs", "-d", wd+"/testing/unsquashFirefox", "-o", strconv.Itoa(int(ai.Offset)), aiFil.Name())
-	start := time.Now()
-	err = cmd.Run()
-	if err != nil {
-		b.Fatal(err)
-	}
-	unsquashTime := time.Since(start)
-	start = time.Now()
-	rdr, err := NewSquashfsReader(io.NewSectionReader(aiFil, ai.Offset, stat.Size()-ai.Offset))
-	if err != nil {
-		b.Fatal(err)
-	}
-	errs := rdr.ExtractTo(wd + "/testing/firefox")
-	if len(errs) > 0 {
-		b.Fatal(errs)
-	}
-	libTime := time.Since(start)
-	b.Log("Unsqushfs:", unsquashTime.Round(time.Millisecond))
-	b.Log("Library:", libTime.Round(time.Millisecond))
-	b.Log("unsquashfs is " + strconv.FormatFloat(float64(libTime.Milliseconds())/float64(unsquashTime.Milliseconds()), 'f', 2, 64) + "x faster")
-}
-
-func downloadTestAppImage(dir string) error {
-	//seems to time out on slow connections. Might fix that at some point... or not. It's just a test...
-	os.Mkdir(dir, os.ModePerm)
-	appImage, err := os.Create(dir + "/" + appImageName)
-	if err != nil {
-		return err
-	}
-	defer appImage.Close()
-	check := http.Client{
-		CheckRedirect: func(r *http.Request, _ []*http.Request) error {
-			r.URL.Opaque = r.URL.Path
-			return nil
-		},
-	}
-	resp, err := check.Get(downloadURL)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-	_, err = io.Copy(appImage, resp.Body)
-	if err != nil {
-		return err
-	}
-	return nil
-}
-
-func TestCreateSquashFromAppImage(t *testing.T) {
-	wd, err := os.Getwd()
-	if err != nil {
-		t.Fatal(err)
-	}
-	err = os.Mkdir(wd+"/testing", 0777)
-	if err != nil && !os.IsExist(err) {
-		t.Fatal(err)
-	}
-	_, err = os.Open(wd + "/testing/" + appImageName)
-	if os.IsNotExist(err) {
-		err = downloadTestAppImage(wd + "/testing")
-		if err != nil {
-			t.Fatal(err)
-		}
-		_, err = os.Open(wd + "/testing/" + appImageName)
-		if err != nil {
-			t.Fatal(err)
-		}
-	} else if err != nil {
-		t.Fatal(err)
-	}
-	ai := goappimage.NewAppImage(wd + "/testing/" + appImageName)
-	aiFil, err := os.Open(wd + "/testing/" + appImageName)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer aiFil.Close()
-	aiFil.Seek(ai.Offset, 0)
-	os.Remove(wd + "/testing/" + appImageName + ".squashfs")
-	aiSquash, err := os.Create(wd + "/testing/" + appImageName + ".squashfs")
-	if err != nil {
-		t.Fatal(err)
-	}
-	_, err = io.Copy(aiSquash, aiFil)
-	if err != nil {
-		t.Fatal(err)
-	}
-}

squashfs_test.go

@@ -0,0 +1,187 @@
+package squashfs_test
+
+//Actually proper tests go here.
+
+import (
+	"errors"
+	"io"
+	"io/fs"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/CalebQ42/squashfs"
+)
+
+const (
+	squashfsURL  = "https://darkstorm.tech/LinuxPATest.sfs"
+	squashfsName = "LinuxPATest.sfs"
+
+	filePath = "PortableApps/Notepad++Portable/App/DefaultData/Config/contextMenu.xml"
+)
+
+func preTest(dir string) (fil *os.File, err error) {
+	fil, err = os.Open(filepath.Join(dir, squashfsName))
+	if err != nil {
+		_, err = os.Open(dir)
+		if os.IsNotExist(err) {
+			err = os.Mkdir(dir, 0755)
+		}
+		if err != nil {
+			return
+		}
+		os.Remove(filepath.Join(dir, squashfsName))
+		fil, err = os.Create(filepath.Join(dir, squashfsName))
+		if err != nil {
+			return
+		}
+		var resp *http.Response
+		resp, err = http.DefaultClient.Get(squashfsURL)
+		if err != nil {
+			return
+		}
+		_, err = io.Copy(fil, resp.Body)
+		if err != nil {
+			return
+		}
+	}
+	_, err = exec.LookPath("unsquashfs")
+	if err != nil {
+		return
+	}
+	_, err = exec.LookPath("mksquashfs")
+	return
+}
+
+func TestMisc(t *testing.T) {
+	tmpDir := "testing"
+	fil, err := preTest(tmpDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	rdr, err := squashfs.NewReader(fil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_ = rdr
+	// Put testing here
+	t.Fatal("UM")
+}
+
+func BenchmarkRace(b *testing.B) {
+	// tmpDir := b.TempDir()
+	tmpDir := "testing"
+	fil, err := preTest(tmpDir)
+	if err != nil {
+		b.Fatal(err)
+	}
+	libPath := filepath.Join(tmpDir, "ExtractLib")
+	unsquashPath := filepath.Join(tmpDir, "ExtractSquashfs")
+	os.RemoveAll(libPath)
+	os.RemoveAll(unsquashPath)
+	var libTime, unsquashTime time.Duration
+	start := time.Now()
+	rdr, err := squashfs.NewReader(fil)
+	if err != nil {
+		b.Fatal(err)
+	}
+	err = rdr.ExtractTo(libPath)
+	if err != nil {
+		b.Fatal(err)
+	}
+	libTime = time.Since(start)
+	cmd := exec.Command("unsquashfs", "-d", unsquashPath, fil.Name())
+	start = time.Now()
+	err = cmd.Run()
+	if err != nil {
+		b.Fatal(err)
+	}
+	unsquashTime = time.Since(start)
+	b.Log("Library took:", libTime.Round(time.Millisecond))
+	b.Log("unsquashfs took:", unsquashTime.Round(time.Millisecond))
+	b.Log("unsquashfs is", strconv.FormatFloat(float64(libTime.Milliseconds())/float64(unsquashTime.Milliseconds()), 'f', 2, 64), "times faster")
+}
+
+func TestExtractQuick(t *testing.T) {
+
+	//First, setup everything and extract the archive using the library and unsquashfs
+
+	// tmpDir := b.TempDir()
+	tmpDir := "testing"
+	fil, err := preTest(tmpDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	libPath := filepath.Join(tmpDir, "ExtractLib")
+	unsquashPath := filepath.Join(tmpDir, "ExtractSquashfs")
+	os.RemoveAll(libPath)
+	os.RemoveAll(unsquashPath)
+	rdr, err := squashfs.NewReader(fil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	op := squashfs.DefaultOptions()
+	op.Verbose = true
+	err = rdr.ExtractWithOptions(libPath, op)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cmd := exec.Command("unsquashfs", "-d", unsquashPath, fil.Name())
+	err = cmd.Run()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	//Then compare the sizes and existance between the two (using unsquashfs as a reference).
+	//If the file doesn't exist, or the size is different, we exit.
+	//TODO: Add long test that checks contents.
+
+	squashFils := os.DirFS(unsquashPath)
+	err = fs.WalkDir(squashFils, ".", func(path string, d fs.DirEntry, _ error) error {
+		libFil, e := os.Open(filepath.Join(libPath, path))
+		if e != nil {
+			return e
+		}
+		stat, _ := d.Info()
+		libStat, _ := libFil.Stat()
+		if stat.Size() != libStat.Size() {
+			t.Log(path, "not the same size between library and unsquashfs")
+			t.Log("File is", libStat.Size())
+			t.Log("Should be", stat.Size())
+			return errors.New("file not the correct size")
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Fatal("end")
+}
+
+func TestSingleFile(t *testing.T) {
+	tmpDir := "testing"
+	fil, err := preTest(tmpDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	os.Remove(filepath.Base(filePath))
+	rdr, err := squashfs.NewReader(fil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	f, err := rdr.Open(filePath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	op := squashfs.DefaultOptions()
+	op.Verbose = true
+	err = f.(*squashfs.File).ExtractWithOptions("testing", op)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Fatal("HI")
+}

superblock.go

@@ -1,31 +1,22 @@
 package squashfs
 
-//The types of compression supported by squashfs.
-const (
-	GzipCompression = 1 + iota
-	LzmaCompression
-	LzoCompression
-	XzCompression
-	Lz4Compression
-	ZstdCompression
-)
+import "math"
 
-//Superblock contains important information about a squashfs file. Located at the very front of the archive.
 type superblock struct {
 	Magic            uint32
 	InodeCount       uint32
-	CreationTime     uint32
+	ModTime          uint32
 	BlockSize        uint32
 	FragCount        uint32
-	CompressionType  uint16
+	CompType         uint16
 	BlockLog         uint16
 	Flags            uint16
-	IDCount          uint16
-	MajorVersion     uint16
-	MinorVersion     uint16
+	IdCount          uint16
+	VerMaj           uint16
+	VerMin           uint16
 	RootInodeRef     uint64
-	BytesUsed        uint64
-	IDTableStart     uint64
+	Size             uint64
+	IdTableStart     uint64
 	XattrTableStart  uint64
 	InodeTableStart  uint64
 	DirTableStart    uint64
@@ -33,36 +24,57 @@ type superblock struct {
 	ExportTableStart uint64
 }
 
-//SuperblockFlags is the parsed version of Superblock.Flags
-type superblockFlags struct {
-	UncompressedInodes    bool
-	UncompressedData      bool
-	Check                 bool
-	UncompressedFragments bool
-	NoFragments           bool
-	AlwaysFragments       bool
-	Duplicates            bool
-	Exportable            bool
-	UncompressedXattr     bool
-	NoXattr               bool
-	CompressorOptions     bool
-	UncompressedIDs       bool
+func (s superblock) checkMagic() bool {
+	return s.Magic == 0x73717368
 }
 
-//GetFlags returns a SuperblockFlags for a given superblock.
-func (s *superblock) GetFlags() superblockFlags {
-	return superblockFlags{
-		UncompressedInodes:    s.Flags&0x1 == 0x1,
-		UncompressedData:      s.Flags&0x2 == 0x2,
-		Check:                 s.Flags&0x4 == 0x4,
-		UncompressedFragments: s.Flags&0x8 == 0x8,
-		NoFragments:           s.Flags&0x10 == 0x10,
-		AlwaysFragments:       s.Flags&0x20 == 0x20,
-		Duplicates:            s.Flags&0x40 == 0x40,
-		Exportable:            s.Flags&0x80 == 0x80,
-		UncompressedXattr:     s.Flags&0x100 == 0x100,
-		NoXattr:               s.Flags&0x200 == 0x200,
-		CompressorOptions:     s.Flags&0x400 == 0x400,
-		UncompressedIDs:       s.Flags&0x800 == 0x800,
-	}
+func (s superblock) checkBlockLog() bool {
+	return s.BlockLog == uint16(math.Log2(float64(s.BlockSize)))
+}
+
+func (s superblock) checkVersion() bool {
+	return s.VerMaj == 4 && s.VerMin == 0
+}
+
+func (s superblock) uncompressedInodes() bool {
+	return s.Flags&0x1 == 0x1
+}
+
+func (s superblock) uncompressedData() bool {
+	return s.Flags&0x2 == 0x2
+}
+func (s superblock) uncompressedFragments() bool {
+	return s.Flags&0x8 == 0x8
+}
+
+func (s superblock) noFragments() bool {
+	return s.Flags&0x10 == 0x10
+}
+
+func (s superblock) alwaysFragment() bool {
+	return s.Flags&0x20 == 0x20
+}
+
+func (s superblock) duplicates() bool {
+	return s.Flags&0x40 == 0x40
+}
+
+func (s superblock) exportable() bool {
+	return s.Flags&0x80 == 0x80
+}
+
+func (s superblock) uncompressedXattrs() bool {
+	return s.Flags&0x100 == 0x100
+}
+
+func (s superblock) noXattrs() bool {
+	return s.Flags&0x200 == 0x200
+}
+
+func (s superblock) compressionOptions() bool {
+	return s.Flags&0x400 == 0x400
+}
+
+func (s superblock) uncompressedIDs() bool {
+	return s.Flags&0x800 == 0x800
 }

writer.go

@@ -1,209 +0,0 @@
-package squashfs
-
-import (
-	"errors"
-	"io"
-	"log"
-	"os"
-	"path"
-	"sort"
-	"strings"
-	"syscall"
-
-	"github.com/CalebQ42/squashfs/internal/compression"
-)
-
-type fileHolder struct {
-	reader      io.Reader
-	path        string
-	name        string
-	symLocation string
-	UID         int
-	GUID        int
-	perm        int
-	folder      bool
-	symlink     bool
-}
-
-//Writer is used to creaste squashfs archives. Currently unusable
-//TODO: Make usable
-type Writer struct {
-	compressor      compression.Compressor
-	structure       map[string][]*fileHolder
-	symlinkTable    map[string]string //[oldpath]newpath
-	uidGUIDTable    []int
-	compressionType int
-	allowErrors     bool
-}
-
-//NewWriter creates a new with the default options (Gzip compression and allow errors)
-func NewWriter() (*Writer, error) {
-	return NewWriterWithOptions(GzipCompression, true)
-}
-
-//NewWriterWithOptions creates a new squashfs.Writer with the given options.
-//compressionType can be of any types, except LZO (which this library doesn't have support for yet)
-//allowErrors determines if, when adding folders, it allows errors encountered with it's sub-directories and instead logs the errors.
-func NewWriterWithOptions(compressionType int, allowErrors bool) (*Writer, error) {
-	if compressionType < 0 || compressionType > 6 {
-		return nil, errors.New("Incorrect compression type")
-	}
-	if compressionType == 3 {
-		return nil, errors.New("LZO compression is not (currently) supported")
-	}
-	return &Writer{
-		structure: map[string][]*fileHolder{
-			"/": make([]*fileHolder, 0),
-		},
-		symlinkTable:    make(map[string]string),
-		compressionType: compressionType,
-		allowErrors:     allowErrors,
-	}, nil
-}
-
-//AddFile attempts to add an os.File to the archive at it's root.
-func (w *Writer) AddFile(file *os.File) error {
-	return w.AddFileToFolder("/", file)
-}
-
-//AddFileToFolder adds the given file to the squashfs archive, placing it inside the given folder.
-func (w *Writer) AddFileToFolder(folder string, file *os.File) error {
-	name := path.Base(file.Name())
-	if !strings.HasSuffix(folder, "/") {
-		folder += "/"
-	}
-	return w.AddFileTo(folder+name, file)
-}
-
-//AddFileTo adds the given file to the squashfs archive at the given filepath.
-func (w *Writer) AddFileTo(filepath string, file *os.File) error {
-	filepath = path.Clean(filepath)
-	if !strings.HasPrefix(filepath, "/") {
-		filepath = "/" + filepath
-	}
-	var holder fileHolder
-	holder.path, holder.name = path.Split(filepath)
-	holder.reader = file
-	stat, err := file.Stat()
-	if err != nil {
-		return err
-	}
-	holder.folder = stat.IsDir()
-	holder.symlink = (stat.Mode()&os.ModeSymlink == os.ModeSymlink)
-	holder.perm = int(stat.Mode().Perm())
-	//Thanks to https://stackoverflow.com/questions/58179647/getting-uid-and-gid-of-a-file for uid and guid getting
-	if stat, ok := stat.Sys().(*syscall.Stat_t); ok {
-		holder.UID = int(stat.Uid)
-		holder.GUID = int(stat.Gid)
-	}
-	if sort.SearchInts(w.uidGUIDTable, holder.UID) == len(w.uidGUIDTable) {
-		w.uidGUIDTable = append(w.uidGUIDTable, holder.UID)
-		sort.Ints(w.uidGUIDTable)
-	}
-	if sort.SearchInts(w.uidGUIDTable, holder.GUID) == len(w.uidGUIDTable) {
-		w.uidGUIDTable = append(w.uidGUIDTable, holder.GUID)
-		sort.Ints(w.uidGUIDTable)
-	}
-	if holder.symlink {
-		target, err := os.Readlink(file.Name())
-		if err != nil {
-			return err
-		}
-		holder.symLocation = target
-	} else if holder.folder {
-		subDirNames, err := file.Readdirnames(-1)
-		if err != nil {
-			return err
-		}
-		dirsAdded := make([]string, 0)
-		for _, subDir := range subDirNames {
-			fil, err := os.Open(file.Name() + subDir)
-			if err != nil {
-				return err
-			}
-			err = w.AddFileToFolder(holder.path+"/"+holder.name, fil)
-			if err != nil && !w.allowErrors {
-				for _, dir := range dirsAdded {
-					w.Remove(dir)
-				}
-				return err
-			} else if err != nil {
-				log.Println("Error while adding", fil.Name())
-				log.Println(err)
-			}
-			if !w.allowErrors {
-				dirsAdded = append(dirsAdded, holder.path+"/"+holder.name)
-			}
-		}
-	} else if !stat.Mode().IsRegular() {
-		return errors.New("Unsupported file type " + file.Name())
-	}
-	w.structure[holder.path] = append(w.structure[holder.path], &holder)
-	return nil
-}
-
-//AddReaderTo adds the data from the given reader to the archive as a file located at the given filepath.
-//Data from the reader is not read until the squashfs archive is writen.
-//If the given reader implements io.Closer, it will be closed after it is fully read.
-func (w *Writer) AddReaderTo(filepath string, reader io.Reader) error {
-	filepath = path.Clean(filepath)
-	if !strings.HasPrefix(filepath, "/") {
-		filepath = "/" + filepath
-	}
-	var holder fileHolder
-	holder.path, holder.name = path.Split(filepath)
-	holder.reader = reader
-	w.structure[holder.path] = append(w.structure[holder.path], &holder)
-	return nil
-}
-
-//Remove tries to remove the file(s) at the given filepath. If wildcards are used, it will remove all files that match.
-//Returns true if one or more files are removed.
-func (w *Writer) Remove(filepath string) bool {
-	var matchFound bool
-	filepath = path.Clean(filepath)
-	if !strings.HasPrefix(filepath, "/") {
-		filepath = "/" + filepath
-	}
-	dir, name := path.Split(filepath)
-	for structDir, files := range w.structure {
-		if match, _ := path.Match(dir, structDir); match {
-			for i, fil := range files {
-				if match, _ = path.Match(name, fil.name); match {
-					matchFound = true
-					if i != len(files)-1 {
-						w.structure[structDir] = append(w.structure[structDir][:i], w.structure[structDir][i+1:]...)
-					} else {
-						w.structure[structDir] = w.structure[structDir][:i]
-					}
-				}
-			}
-		}
-	}
-	return matchFound
-}
-
-//FixSymlinks will scan through the squashfs archive and try to find broken symlinks and fix them.
-//This done by replacing the symlink with the target file and then pointing other symlinks to that file.
-//
-//If this is not run before writing, you may end up with broken symlinks.
-func (w *Writer) FixSymlinks() error {
-	//TODO
-	return errors.New("DON'T")
-}
-
-//WriteToFilename creates the squashfs archive with the given filepath.
-func (w *Writer) WriteToFilename(filepath string) error {
-	newFil, err := os.Create(filepath)
-	if err != nil {
-		return err
-	}
-	_, err = w.WriteTo(newFil)
-	return err
-}
-
-//WriteTo attempts to write the archive to the given io.Writer.
-func (w *Writer) WriteTo(write io.Writer) (int64, error) {
-	//TODO
-	return 0, errors.New("I SAID DON'T")
-}

writer_compression_options.go

@@ -1,15 +0,0 @@
-package squashfs
-
-//TODO: Allow settings the options
-
-// func (w *Writer) SetGzipOptions() error {}
-
-// func (w *Writer) SetLzmaOptions() error {}
-
-// func (w *Writer) SetLzoOptions() error {}
-
-// func (w *Writer) SetXzOptions() error {}
-
-// func (w *Writer) SetLz4Options() error {}
-
-// func (w *Writer) SetZstdOptions() error {}