unarr

README

go-unarr

Golang bindings for the unarr library from sumatrapdf.

unarr is a decompression library and CLI for RAR, TAR, ZIP and 7z archives.

GoDoc

See https://pkg.go.dev/github.com/gen2brain/go-unarr

Build tags

• extlib - use external libunarr library
• pkgconfig - enable pkg-config (used with extlib)
• static - use static library (used with pkgconfig)

Install CLI

go install github.com/gen2brain/go-unarr/cmd/unarr@latest

Example

unarr ./example.7z ./example/

Build

For one-off builds:

go build -o ./unarr ./cmd/unarr/*.go

For multi-platform cross-compile builds:

goreleaser --snapshot --skip-publish --rm-dist

Library Examples

Install Library

go get -v github.com/gen2brain/go-unarr

Open archive

a, err := unarr.NewArchive("test.7z")
if err != nil {
    panic(err)
}
defer a.Close()

Read first entry from archive

err := a.Entry()
if err != nil {
    panic(err)
}

data, err := a.ReadAll()
if err != nil {
    panic(err)
}

List contents of archive

list, err := a.List()
if err != nil {
    panic(err)
}

Read known filename from archive

err := a.EntryFor("filename.txt")
if err != nil {
    panic(err)
}

data, err := a.ReadAll()
if err != nil {
    panic(err)
}

Read first 8 bytes of the entry

err := a.Entry()
if err != nil {
    panic(err)
}

data := make([]byte, 8)

n, err := a.Read(data)
if err != nil {
    panic(err)
}

Read all entries from archive

for {
    err := a.Entry()
    if err != nil {
        if err == io.EOF {
            break
        } else {
            panic(err)
        }
    }

    data, err := a.ReadAll()
    if err != nil {
        panic(err)
    }
}

Extract contents of archive to destination path

_, err := a.Extract("/tmp/path")
if err != nil {
    panic(err)
}

Documentation

Overview

Package unarr is a decompression library for RAR, TAR, ZIP and 7z archives.

Index

• Variables
• type Archive
  • func NewArchive(path string) (a *Archive, err error)
  • func NewArchiveFromMemory(b []byte) (a *Archive, err error)
  • func NewArchiveFromReader(r io.Reader) (a *Archive, err error)
  • func (a *Archive) Close() (err error)
  • func (a *Archive) Entry() error
  • func (a *Archive) EntryAt(off int64) error
  • func (a *Archive) EntryFor(name string) error
  • func (a *Archive) Extract(path string) (contents []string, err error)
  • func (a *Archive) List() (contents []string, err error)
  • func (a *Archive) ModTime() time.Time
  • func (a *Archive) Name() string
  • func (a *Archive) Offset() int64
  • func (a *Archive) RawName() string
  • func (a *Archive) Read(b []byte) (n int, err error)
  • func (a *Archive) ReadAll() ([]byte, error)
  • func (a *Archive) Seek(offset int64, whence int) (int64, error)
  • func (a *Archive) Size() int

Variables

var (
	ErrOpenFile    = errors.New("unarr: open file failed")
	ErrOpenMemory  = errors.New("unarr: open memory failed")
	ErrOpenArchive = errors.New("unarr: no valid RAR, ZIP, 7Z or TAR archive")
	ErrEntry       = errors.New("unarr: failed to parse entry")
	ErrEntryAt     = errors.New("unarr: failed to parse entry at")
	ErrEntryFor    = errors.New("unarr: failed to parse entry for")
	ErrSeek        = errors.New("unarr: seek failed")
	ErrRead        = errors.New("unarr: read failure")
	ErrUnsafePath  = errors.New("unarr: entry path is not local")
)

Types

type Archive

type Archive struct {
	// contains filtered or unexported fields
}

Archive represents unarr archive

func NewArchive

func NewArchive(path string) (a *Archive, err error)

NewArchive returns new unarr Archive

func NewArchiveFromMemory

func NewArchiveFromMemory(b []byte) (a *Archive, err error)

NewArchiveFromMemory returns new unarr Archive from byte slice.

The byte slice must not be modified until the archive is closed.

func NewArchiveFromReader

func NewArchiveFromReader(r io.Reader) (a *Archive, err error)

NewArchiveFromReader returns new unarr Archive from io.Reader

func (*Archive) Close

func (a *Archive) Close() (err error)

Close closes the underlying unarr archive

func (*Archive) Entry

func (a *Archive) Entry() error

Entry reads the next archive entry.

io.EOF is returned when there is no more to be read from the archive.

func (*Archive) EntryAt

func (a *Archive) EntryAt(off int64) error

EntryAt reads the archive entry at the given offset

func (*Archive) EntryFor

func (a *Archive) EntryFor(name string) error

EntryFor reads the (first) archive entry associated with the given name

func (*Archive) Extract

func (a *Archive) Extract(path string) (contents []string, err error)

Extract extracts archive to destination path

func (*Archive) List

func (a *Archive) List() (contents []string, err error)

List lists the contents of archive

func (*Archive) ModTime

func (a *Archive) ModTime() time.Time

ModTime returns the stored modification time of the current entry

func (*Archive) Name

func (a *Archive) Name() string

Name returns the name of the current entry as UTF-8 string

func (*Archive) Offset

func (a *Archive) Offset() int64

Offset returns the stream offset of the current entry, for use with EntryAt

func (*Archive) RawName

func (a *Archive) RawName() string

RawName returns the name of the current entry as raw string

func (*Archive) Read

func (a *Archive) Read(b []byte) (n int, err error)

Read reads up to len(b) bytes of the current entry into b, advancing the read offset pointer.

Returns the actual number of bytes read, io.EOF at the end of the entry.

func (*Archive) ReadAll

func (a *Archive) ReadAll() ([]byte, error)

ReadAll reads current entry and returns data

func (*Archive) Seek

func (a *Archive) Seek(offset int64, whence int) (int64, error)

Seek moves the read offset pointer interpreted according to whence.

Returns the new offset.

func (*Archive) Size

func (a *Archive) Size() int

Size returns the total size of uncompressed data of the current entry