You can lookup an inode via a string path now

Removed DecompressCopy (as I wasn't using it)
Started work on fragments

README.md

@@ -15,6 +15,7 @@ Thanks also to [distri's squashfs library](https://github.com/distr1/distri/tree
 * Reading inodes
 * Reading directories
 * Basic gzip compression (Shouldn't be too hard to implement other, but for right now, this works)
+* Listing all files via a string slice
 
 # Not Working (Yet). Roughly in order.
 
@@ -31,4 +32,4 @@ Thanks also to [distri's squashfs library](https://github.com/distr1/distri/tree
 
 # Where I'm at.
 
-* I CAN READ THE ENTIRE DIRECTORY!!!!! (This is a big ol' step)
+* Started work on fragments

compression.go

@@ -8,7 +8,6 @@ import (
 
 type Decompressor interface {
 	Decompress(io.Reader) ([]byte, error)
-	DecompressCopy(*io.Writer, *io.SectionReader) error
 }
 
 type ZlibDecompressor struct{}
@@ -25,15 +24,3 @@ func (z *ZlibDecompressor) Decompress(r io.Reader) ([]byte, error) {
 	}
 	return data.Bytes(), nil
 }
-
-func (z *ZlibDecompressor) DecompressCopy(w *io.Writer, r *io.SectionReader) error {
-	rdr, err := zlib.NewReader(r)
-	if err != nil {
-		return err
-	}
-	_, err = io.Copy(*w, rdr)
-	if err != nil {
-		return err
-	}
-	return err
-}

fragment.go

@@ -0,0 +1,48 @@
+package squashfs
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+
+	"github.com/CalebQ42/GoSquashfs/internal/inode"
+)
+
+type FragmentEntryRaw struct {
+	Start uint64
+	Size  uint32
+}
+
+type FragmentEntry struct {
+	start      uint64
+	size       uint32
+	compressed bool
+}
+
+//NewFragmentEntry reads a fragment entry from the given io.Reader.
+func (r *Reader) NewFragmentEntry(rdr *io.Reader) (*FragmentEntry, error) {
+	var entry FragmentEntry
+	var raw FragmentEntryRaw
+	err := binary.Read(*rdr, binary.LittleEndian, &raw)
+	if err != nil {
+		return nil, err
+	}
+	entry.start = raw.Start
+	entry.compressed = raw.Size&0x1000000 == 0x1000000
+	entry.size = raw.Size &^ 0x1000000
+	return &entry, nil
+}
+
+//GetFragmentFromInode returns the fragment data for a given inode
+func (r *Reader) GetFragmentFromInode(in *inode.Inode) ([]byte, error) {
+	if in.Type != inode.BasicFileType {
+		return nil, errors.New("Only basic file is supported right now")
+	}
+	bf := in.Info.(inode.BasicFile)
+	var size uint32
+	if bf.Init.BlockStart == 0 {
+		size = bf.Init.Size
+	} else {
+		size = bf.BlockSizes
+	}
+}

internal/inode/process.go

@@ -15,11 +15,11 @@ type Inode struct {
 }
 
 //ProcessInode tries to read an inode from the BlockReader
-func ProcessInode(br io.Reader, blockSize uint32) (Inode, error) {
+func ProcessInode(br io.Reader, blockSize uint32) (*Inode, error) {
 	var head Header
 	err := binary.Read(br, binary.LittleEndian, &head)
 	if err != nil {
-		return Inode{}, err
+		return nil, err
 	}
 	var info interface{}
 	switch head.InodeType {
@@ -27,97 +27,97 @@ func ProcessInode(br io.Reader, blockSize uint32) (Inode, error) {
 		var inode BasicDirectory
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicFileType:
 		inode, err := NewBasicFile(br, blockSize)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicSymlinkType:
 		inode, err := NewBasicSymlink(br)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicBlockDeviceType:
 		var inode BasicDevice
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicCharDeviceType:
 		var inode BasicDevice
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicFifoType:
 		var inode BasicIPC
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case BasicSocketType:
 		var inode BasicIPC
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtDirType:
 		inode, err := NewExtendedDirectory(br)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtFileType:
 		inode, err := NewExtendedFile(br, blockSize)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtSymlinkType:
 		inode, err := NewExtendedSymlink(br)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtBlockDeviceType:
 		var inode ExtendedDevice
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtCharDeviceType:
 		var inode ExtendedDevice
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtFifoType:
 		var inode ExtendedIPC
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	case ExtSocketType:
 		var inode ExtendedIPC
 		err = binary.Read(br, binary.LittleEndian, &inode)
 		if err != nil {
-			return Inode{}, err
+			return nil, err
 		}
 		info = inode
 	}
-	return Inode{
+	return &Inode{
 		Type:   int(head.InodeType),
 		Header: head,
 		Info:   info,

squashfsreader.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"strings"
 
 	"github.com/CalebQ42/GoSquashfs/internal/directory"
 	"github.com/CalebQ42/GoSquashfs/internal/inode"
@@ -14,6 +15,17 @@ const (
 	magic = 0x73717368
 )
 
+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")
+)
+
+//Reader processes and reads a squashfs archive.
+//TODO: Give a way to actually read files :P
 type Reader struct {
 	r            io.ReaderAt
 	super        Superblock
@@ -22,6 +34,7 @@ type Reader struct {
 	dirs         []*directory.Directory
 }
 
+//NewSquashfsReader returns a new squashfs.Reader from an io.ReaderAt
 func NewSquashfsReader(r io.ReaderAt) (*Reader, error) {
 	var rdr Reader
 	rdr.r = r
@@ -30,25 +43,43 @@ func NewSquashfsReader(r io.ReaderAt) (*Reader, error) {
 		return nil, err
 	}
 	if rdr.super.Magic != magic {
-		return nil, errors.New("doesn't have magic number, probably isn't a squashfs")
+		return nil, ErrNoMagic
 	}
 	rdr.flags = rdr.super.GetFlags()
 	switch rdr.super.CompressionType {
 	case gzipCompression:
 		rdr.decompressor = &ZlibDecompressor{}
 	default:
-		return nil, errors.New("Unsupported compression type")
+		return nil, ErrIncompatibleCompression
 	}
 	if rdr.flags.CompressorOptions {
 		//TODO: parse compressor options
-		fmt.Println("Compressor options is NOT currently supported")
-		return nil, errors.New("Has compressor options")
+		return nil, ErrCompressorOptions
 	}
 	return &rdr, nil
 }
 
+//GetFilesList returns a list of ALL files in the squashfs, going down every folder.
+//Paths that terminate in a folder end with /
+func (r *Reader) GetFilesList() ([]string, error) {
+	inoderdr, err := r.NewBlockReaderFromInodeRef(r.super.RootInodeRef)
+	if err != nil {
+		return nil, err
+	}
+	i, err := inode.ProcessInode(inoderdr, r.super.BlockSize)
+	if err != nil {
+		return nil, err
+	}
+	paths, err := r.readDir(i)
+	if err != nil {
+		return nil, err
+	}
+	return paths, nil
+}
+
+//readDir returns a list of all decendents of a given inode. Inode given MUST be a directory type.
 func (r *Reader) readDir(i *inode.Inode) (paths []string, err error) {
-	dir, err := r.ReadDirFromInode(*i)
+	dir, err := r.ReadDirFromInode(i)
 	if err != nil {
 		return
 	}
@@ -77,20 +108,10 @@ func (r *Reader) readDir(i *inode.Inode) (paths []string, err error) {
 }
 
 func (r *Reader) readDirTable() error {
-	inoderdr, err := r.NewBlockReaderFromInodeRef(r.super.RootInodeRef)
+	paths, err := r.GetFilesList()
 	if err != nil {
 		return err
 	}
-	i, err := inode.ProcessInode(inoderdr, r.super.BlockSize)
-	if err != nil {
-		return err
-	}
-	paths, err := r.readDir(&i)
-	if err != nil {
-		return err
-	}
-	for _, path := range paths {
-		fmt.Println(path)
-	}
+	fmt.Println(strings.Join(paths, "\n"))
 	return nil
 }

utils.go

@@ -3,11 +3,17 @@ package squashfs
 import (
 	"errors"
 	"io"
+	"strings"
 
 	"github.com/CalebQ42/GoSquashfs/internal/directory"
 	"github.com/CalebQ42/GoSquashfs/internal/inode"
 )
 
+var (
+	//ErrNotFound means that the given path is NOT present in the archive
+	ErrNotFound = errors.New("Path not found")
+)
+
 //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.
@@ -19,7 +25,9 @@ func processInodeRef(inodeRef uint64) (tableOffset uint64, metaOffset uint64) {
 	return
 }
 
-func (r *Reader) ReadDirFromInode(i inode.Inode) (*directory.Directory, error) {
+//ReadDirFromInode returns a fully populated directory.Directory from a given inode.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 uint16
@@ -50,6 +58,7 @@ func (r *Reader) ReadDirFromInode(i inode.Inode) (*directory.Directory, error) {
 	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.NewBlockReader(int64(r.super.InodeTableStart + uint64(en.Header.InodeOffset)))
 	if err != nil {
@@ -63,5 +72,45 @@ func (r *Reader) GetInodeFromEntry(en *directory.Entry) (*inode.Inode, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &i, nil
+	return i, nil
+}
+
+//GetInodeFromPath returns the inode at the given path, relative to root.
+//The given path can start or without "/".
+func (r *Reader) GetInodeFromPath(path string) (*inode.Inode, error) {
+	path = strings.TrimSuffix(strings.TrimPrefix(path, "/"), "/")
+	pathDirs := strings.Split(path, "/")
+	rdr, err := r.NewBlockReaderFromInodeRef(r.super.RootInodeRef)
+	if err != nil {
+		return nil, err
+	}
+	curInodeDir, err := inode.ProcessInode(rdr, r.super.BlockSize)
+	if err != nil {
+		return nil, err
+	}
+	for depth := 0; depth < len(pathDirs); depth++ {
+		if curInodeDir.Type != inode.BasicDirectoryType && curInodeDir.Type != inode.ExtDirType {
+			return nil, ErrNotFound
+		}
+		dir, err := r.ReadDirFromInode(curInodeDir)
+		if err != nil {
+			return nil, err
+		}
+		for _, entry := range dir.Entries {
+			if entry.Name == pathDirs[depth] {
+				if depth == len(pathDirs)-1 {
+					in, err := r.GetInodeFromEntry(&entry)
+					if err != nil {
+						return nil, err
+					}
+					return in, nil
+				}
+				curInodeDir, err = r.GetInodeFromEntry(&entry)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+	}
+	return nil, ErrNotFound
 }