Set main folder permission

Added helper extraction functions
chmod & chown is now set after a folder's extraction to prevent permission issues

.gitignore

@@ -1 +1,2 @@
-testing
+testing
+/go-unsquashfs

README.md

@@ -1,8 +1,8 @@
-# squashfs (WIP)
+# squashfs
 
 [![PkgGoDev](https://pkg.go.dev/badge/github.com/CalebQ42/squashfs)](https://pkg.go.dev/github.com/CalebQ42/squashfs) [![Go Report Card](https://goreportcard.com/badge/github.com/CalebQ42/squashfs)](https://goreportcard.com/report/github.com/CalebQ42/squashfs)
 
-A PURE Go library to read and write squashfs.
+A PURE Go library to read squashfs. There is currently no plans to add archive creation support as it will almost always be better to just call `mksquashfs`. I could see some possible use cases, but probably won't spend time on it unless it's requested (open a discussion fi you want this feature).
 
 Currently has support for reading squashfs files and extracting files and folders.
 
@@ -14,7 +14,18 @@ Thanks also to [distri's squashfs library](https://github.com/distr1/distri/tree
 ## 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.
+* Socket files are not extracted.
+  * From my research, it seems like a socket file would be useless if it could be created.
+* Fifo files are ignored on `darwin`
 
-## Performance
+## Issues
 
-Testing on a zstd compressed file, my library is anywhere from 5x ~ 7x slower then `unsquashfs`
+* Significantly slower then `unsquashfs` when extracting folders (about 5 ~ 7 times slower on a ~100MB archive using zstd compression)
+  * This seems to be related to above along with the general optimization of `unsquashfs` and it's compression libraries.
+  * The larger the file's tree, the slower the extraction will be. Arch Linux's Live USB's airootfs.sfs takes ~35x longer for a full extraction.
+
+## Recommendations on Usage
+
+Due to the above performance consideration, this library should only be used to access files within the archive without extraction, or to mount it via Fuse.
+
+* Neither of these use cases are largely effected by the issue above.

cmd/go-unsquashfs/main.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/CalebQ42/squashfs"
+)
+
+func main() {
+	verbose := flag.Bool("v", false, "Verbose")
+	ignore := flag.Bool("ip", false, "Ignore Permissions and extract all files/folders with 0755")
+	flag.Parse()
+	if len(flag.Args()) < 2 {
+		fmt.Println("Please provide a file name and extraction path")
+		os.Exit(0)
+	}
+	f, err := os.Open(flag.Arg(0))
+	if err != nil {
+		panic(err)
+	}
+	r, err := squashfs.NewReader(f)
+	if err != nil {
+		panic(err)
+	}
+	op := squashfs.DefaultOptions()
+	op.Verbose = *verbose
+	op.IgnorePerm = *ignore
+	n := time.Now()
+	err = r.ExtractWithOptions(flag.Arg(1), op)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println("Took:", time.Since(n))
+}

internal/threadmanager/manager.go

@@ -0,0 +1,23 @@
+package threadmanager
+
+type Manager struct {
+	c chan int
+}
+
+func NewManager(maxRoutines int) *Manager {
+	m := &Manager{
+		c: make(chan int, maxRoutines),
+	}
+	for i := 0; i < maxRoutines; i++ {
+		m.c <- i
+	}
+	return m
+}
+
+func (m *Manager) Lock() int {
+	return <-m.c
+}
+
+func (m *Manager) Unlock(n int) {
+	m.c <- n
+}

reader_file.go

@@ -8,12 +8,14 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strconv"
 	"strings"
 
 	"github.com/CalebQ42/squashfs/internal/data"
 	"github.com/CalebQ42/squashfs/internal/directory"
 	"github.com/CalebQ42/squashfs/internal/inode"
+	"github.com/CalebQ42/squashfs/internal/threadmanager"
 )
 
 // File represents a file inside a squashfs archive.
@@ -59,6 +61,21 @@ func (f File) Stat() (fs.FileInfo, error) {
 	return newFileInfo(f.e, f.i), nil
 }
 
+// Mode returns the file's fs.FileMode
+func (f File) Mode() fs.FileMode {
+	switch f.e.Type {
+	case inode.Dir:
+		return fs.FileMode(f.i.Perm) | fs.ModeDir
+	case inode.Char:
+		return fs.FileMode(f.i.Perm) | fs.ModeCharDevice
+	case inode.Block:
+		return fs.FileMode(f.i.Perm) | fs.ModeDevice
+	case inode.Sym:
+		return fs.FileMode(f.i.Perm) | fs.ModeSymlink
+	}
+	return fs.FileMode(f.i.Perm)
+}
+
 // 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 {
@@ -71,16 +88,22 @@ func (f File) Read(p []byte) (int, error) {
 }
 
 func (f File) ReadAt(p []byte, off int64) (int, error) {
+	if f.i.Type != inode.Fil && f.i.Type != inode.EFil {
+		return 0, ErrReadNotFile
+	}
 	return f.fullRdr.ReadAt(p, off)
 }
 
 // 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) {
+	if f.i.Type != inode.Fil && f.i.Type != inode.EFil {
+		return 0, ErrReadNotFile
+	}
 	return f.fullRdr.WriteTo(w)
 }
 
-// Close simply nils the underlying reader. Here mostly to satisfy fs.File
+// Close simply nils the underlying reader.
 func (f *File) Close() error {
 	f.rdr = nil
 	return nil
@@ -90,7 +113,7 @@ func (f *File) Close() error {
 // 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")
+		return nil, errors.New("file is not a directory")
 	}
 	ents, err := f.r.readDirectory(f.i)
 	if err != nil {
@@ -197,96 +220,153 @@ func (f File) GetSymlinkFile() *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
+	manager            *threadmanager.Manager
+	LogOutput          io.Writer   //Where error log should write.
+	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.
+	IgnorePerm         bool        //Ignore file's permissions and instead use Perm.
+	Perm               fs.FileMode //Permission to use when IgnorePerm. Defaults to 0755.
+	notFirst           bool
 }
 
-// DefaultOptions is the default ExtractionOptions.
-func DefaultOptions() ExtractionOptions {
-	return ExtractionOptions{
-		FolderPerm: 0755,
+func DefaultOptions() *ExtractionOptions {
+	return &ExtractionOptions{
+		Perm: 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())
+	return f.realExtract(folder, DefaultOptions())
+}
+
+// ExtractVerbose extracts the File to the folder with the Verbose option.
+func (f File) ExtractVerbose(folder string) error {
+	op := DefaultOptions()
+	op.Verbose = true
+	return f.realExtract(folder, op)
+}
+
+// ExtractIgnorePermissions extracts the File to the folder with the IgnorePerm option.
+func (f File) ExtractIgnorePermissions(folder string) error {
+	op := DefaultOptions()
+	op.IgnorePerm = true
+	return f.realExtract(folder, op)
 }
 
 // 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,
-	})
+	op := DefaultOptions()
+	op.DereferenceSymlink = true
+	return f.realExtract(folder, op)
 }
 
 // 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
-		}
+func (f File) ExtractWithOptions(folder string, op *ExtractionOptions) error {
+	if op.Verbose && op.LogOutput != nil {
 		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")
+func (f File) realExtract(folder string, op *ExtractionOptions) (err error) {
+	if op.manager == nil {
+		op.manager = threadmanager.NewManager(runtime.NumCPU())
+	}
+	extDir := folder + "/" + f.e.Name
+	if !op.notFirst {
+		op.notFirst = true
+		if f.IsDir() {
+			extDir = folder
+			_, err = os.Open(folder)
+			if err != nil && os.IsNotExist(err) {
+				err = os.Mkdir(extDir, op.Perm)
+			}
+			if err != nil {
+				if op.Verbose {
+					log.Println("Error while making", folder)
+				}
+				return
+			}
+			if !op.IgnorePerm {
+				defer os.Chmod(extDir, f.Mode())
+				defer os.Chown(extDir, int(f.r.ids[f.i.UidInd]), int(f.r.ids[f.i.GidInd]))
+			}
 		}
-		return err
 	}
 	switch {
 	case f.IsDir():
-		filFS, _ := f.FS()
-		var ents []directory.Entry
-		ents, err = f.r.readDirectory(f.i)
+		if folder != extDir && f.e.Name != "" {
+			//First extract it with a permisive permission.
+			err = os.Mkdir(extDir, op.Perm)
+			if err != nil {
+				if op.Verbose {
+					log.Println("Error while making directory", extDir)
+				}
+				return
+			}
+			//Then set it to it's actual permissions once we're done with it
+			if !op.IgnorePerm {
+				defer os.Chmod(extDir, f.Mode())
+				defer os.Chown(extDir, int(f.r.ids[f.i.UidInd]), int(f.r.ids[f.i.GidInd]))
+			}
+		}
+		var filFS *FS
+		filFS, err = f.FS()
 		if err != nil {
 			if op.Verbose {
-				log.Println("Error while reading children of", f.path())
+				log.Println("Error while converting", f.path(), "to FS")
 			}
 			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)
+		errChan := make(chan error, len(filFS.e))
+		files := make([]directory.Entry, 0)
+		//Focus on making the folder tree first...
+		var i int
+		for i = 0; i < len(filFS.e); i++ {
+			if filFS.e[i].Type == inode.Fil {
+				files = append(files, filFS.e[i])
+			} else {
+				go func(index int) {
+					subF, goErr := f.r.newFile(filFS.e[index], filFS)
+					if goErr != nil {
+						if op.Verbose {
+							log.Println("Error while resolving", extDir)
+						}
+						errChan <- goErr
+						return
+					}
+					errChan <- subF.ExtractWithOptions(extDir, op)
+				}(i)
+			}
+		}
+		for i = 0; i < len(filFS.e)-len(files); i++ {
+			err = <-errChan
+			if err != nil {
+				return err
+			}
+		}
+		//Then we extract the files.
+		for i = 0; i < len(files); i++ {
+			go func(index int) {
+				n := op.manager.Lock()
+				defer op.manager.Unlock(n)
+				subF, goErr := f.r.newFile(files[index], filFS)
 				if goErr != nil {
 					if op.Verbose {
-						log.Println("Error while reading info for", filepath.Join(f.path(), ent.Name))
+						log.Println("Error while resolving", extDir)
 					}
 					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])
+				errChan <- subF.ExtractWithOptions(extDir, op)
+			}(i)
 		}
-		for i := 0; i < len(ents); i++ {
+		for i = 0; i < len(files); i++ {
 			err = <-errChan
 			if err != nil {
 				return err
@@ -294,36 +374,43 @@ func (f File) realExtract(folder string, op ExtractionOptions) error {
 		}
 	case f.IsRegular():
 		var fil *os.File
-		fil, err = os.Create(folder + "/" + f.e.Name)
+		fil, err = os.Create(extDir)
 		if os.IsExist(err) {
-			os.Remove(folder + "/" + f.e.Name)
-			fil, err = os.Create(folder + "/" + f.e.Name)
+			os.Remove(extDir)
+			fil, err = os.Create(extDir)
 			if err != nil {
 				if op.Verbose {
-					log.Println("Error while creating", folder+"/"+f.e.Name)
+					log.Println("Error while creating", extDir)
 				}
 				return err
 			}
 		} else if err != nil {
 			if op.Verbose {
-				log.Println("Error while creating", folder+"/"+f.e.Name)
+				log.Println("Error while creating", extDir)
 			}
 			return err
 		}
+		defer fil.Close()
 		_, err = io.Copy(fil, f)
 		if err != nil {
 			if op.Verbose {
-				log.Println("Error while copying data to", folder+"/"+f.e.Name)
+				log.Println("Error while copying data to", extDir)
 			}
 			return err
 		}
+		if op.IgnorePerm {
+			os.Chmod(extDir, op.Perm|(f.Mode()&fs.ModeType))
+		} else {
+			os.Chmod(extDir, f.Mode())
+			os.Chown(extDir, int(f.r.ids[f.i.UidInd]), int(f.r.ids[f.i.GidInd]))
+		}
 	case 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)
+					log.Println("Symlink path(", symPath, ") is unobtainable:", extDir)
 				}
 				return errors.New("cannot get symlink target")
 			}
@@ -331,7 +418,7 @@ func (f File) realExtract(folder string, op ExtractionOptions) error {
 			err = fil.realExtract(folder, op)
 			if err != nil {
 				if op.Verbose {
-					log.Println("Error while extracting the symlink's file:", folder+"/"+f.e.Name)
+					log.Println("Error while extracting the symlink's file:", extDir)
 				}
 				return err
 			}
@@ -340,31 +427,43 @@ func (f File) realExtract(folder string, op ExtractionOptions) error {
 			fil := f.GetSymlinkFile()
 			if fil == nil {
 				if op.Verbose {
-					log.Println("Symlink path(", symPath, ") is unobtainable:", folder+"/"+f.e.Name)
+					log.Println("Symlink path(", symPath, ") is unobtainable:", extDir)
 				}
 				return errors.New("cannot get symlink target")
 			}
-			extractLoc := filepath.Clean(folder + "/" + filepath.Dir(symPath))
+			extractLoc := filepath.Join(folder, filepath.Dir(symPath))
 			err = fil.realExtract(extractLoc, op)
 			if err != nil {
 				if op.Verbose {
-					log.Println("Error while extracting ", folder+"/"+f.e.Name)
+					log.Println("Error while extracting ", extDir)
 				}
 				return err
 			}
 		}
-		err = os.Symlink(f.SymlinkPath(), folder+"/"+f.e.Name)
+		err = os.Symlink(f.SymlinkPath(), extDir)
 		if os.IsExist(err) {
-			os.Remove(folder + "/" + f.e.Name)
-			err = os.Symlink(f.SymlinkPath(), folder+"/"+f.e.Name)
+			os.Remove(extDir)
+			err = os.Symlink(f.SymlinkPath(), extDir)
 		}
 		if err != nil {
 			if op.Verbose {
-				log.Println("Error while making symlink:", folder+"/"+f.e.Name)
+				log.Println("Error while making symlink:", extDir)
 			}
 			return err
 		}
+		if op.IgnorePerm {
+			os.Chmod(extDir, op.Perm|(f.Mode()&fs.ModeType))
+		} else {
+			os.Chmod(extDir, f.Mode())
+			os.Chown(extDir, int(f.r.ids[f.i.UidInd]), int(f.r.ids[f.i.GidInd]))
+		}
 	case f.isDeviceOrFifo():
+		if runtime.GOOS == "windows" {
+			if op.Verbose {
+				log.Println(extDir, "ignored since it's a device link and can't be created on Windows.")
+			}
+			return nil
+		}
 		_, err = exec.LookPath("mknod")
 		if err != nil {
 			if op.Verbose {
@@ -378,9 +477,15 @@ func (f File) realExtract(folder string, op ExtractionOptions) error {
 		} else if f.i.Type == inode.Block || f.i.Type == inode.EBlock {
 			typ = "b"
 		} else { //Fifo IPC
+			if runtime.GOOS == "darwin" {
+				if op.Verbose {
+					log.Println(extDir, "ignored since it's a Fifo file and can't be created on Darwin.")
+				}
+				return nil
+			}
 			typ = "p"
 		}
-		cmd := exec.Command("mknod", folder+"/"+f.e.Name, typ)
+		cmd := exec.Command("mknod", extDir, typ)
 		if typ != "p" {
 			maj, min := f.deviceDevices()
 			cmd.Args = append(cmd.Args, strconv.Itoa(int(maj)), strconv.Itoa(int(min)))
@@ -392,10 +497,20 @@ func (f File) realExtract(folder string, op ExtractionOptions) error {
 		err = cmd.Run()
 		if err != nil {
 			if op.Verbose {
-				log.Println("Error while running mknod for", folder+"/"+f.e.Name)
+				log.Println("Error while running mknod for", extDir)
 			}
 			return err
 		}
+		if op.IgnorePerm {
+			os.Chmod(extDir, op.Perm|(f.Mode()&fs.ModeType))
+		} else {
+			os.Chmod(extDir, f.Mode())
+			os.Chown(extDir, int(f.r.ids[f.i.UidInd]), int(f.r.ids[f.i.GidInd]))
+		}
+	case f.e.Type == inode.Sock:
+		if op.Verbose {
+			log.Println(extDir, "ignored since it's a socket file.")
+		}
 	default:
 		return errors.New("Unsupported file type. Inode type: " + strconv.Itoa(int(f.i.Type)))
 	}

squashfs_test.go

@@ -18,7 +18,7 @@ import (
 )
 
 const (
-	squashfsURL  = "https://darkstorm.tech/LinuxPATest.sfs"
+	squashfsURL  = "https://darkstorm.tech/files/LinuxPATest.sfs"
 	squashfsName = "LinuxPATest.sfs"
 
 	filePath = "PortableApps/Notepad++Portable/App/DefaultData/Config/contextMenu.xml"
@@ -106,7 +106,6 @@ func BenchmarkRace(b *testing.B) {
 }
 
 func TestExtractQuick(t *testing.T) {
-
 	//First, setup everything and extract the archive using the library and unsquashfs
 
 	// tmpDir := b.TempDir()
@@ -123,8 +122,12 @@ func TestExtractQuick(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	os.RemoveAll(filepath.Join(tmpDir, "testLog.txt"))
+	logFil, _ := os.Create(filepath.Join(tmpDir, "testLog.txt"))
 	op := squashfs.DefaultOptions()
 	op.Verbose = true
+	op.IgnorePerm = true
+	op.LogOutput = logFil
 	err = rdr.ExtractWithOptions(libPath, op)
 	if err != nil {
 		t.Fatal(err)
@@ -176,9 +179,7 @@ func TestSingleFile(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	op := squashfs.DefaultOptions()
-	op.Verbose = true
-	err = f.(*squashfs.File).ExtractWithOptions("testing", op)
+	err = f.(*squashfs.File).ExtractWithOptions("testing", &squashfs.ExtractionOptions{Verbose: true})
 	if err != nil {
 		t.Fatal(err)
 	}