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")
)

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

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 tries to read 'b' bytes into buffer, advancing the read offset pointer.

Returns the actual number of bytes read.

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