Golang restic.Hash函数代码示例

func TestLoadLargeBuffer(t *testing.T) {
	b := mem.New()

	for i := 0; i < 20; i++ {
		data := Random(23+i, rand.Intn(MiB)+500*KiB)

		id := restic.Hash(data)
		err := b.Save(restic.Handle{Name: id.String(), Type: restic.DataFile}, data)
		OK(t, err)

		buf := make([]byte, len(data)+100)
		buf, err = backend.LoadAll(b, restic.Handle{Type: restic.DataFile, Name: id.String()}, buf)
		OK(t, err)

		if len(buf) != len(data) {
			t.Errorf("length of returned buffer does not match, want %d, got %d", len(data), len(buf))
			continue
		}

		if !bytes.Equal(buf, data) {
			t.Errorf("wrong data returned")
			continue
		}
	}
}

func saveFile(t testing.TB, be Saver, filename string, n int) {
	f, err := os.Open(filename)
	if err != nil {
		t.Fatal(err)
	}

	data := make([]byte, n)
	m, err := io.ReadFull(f, data)

	if m != n {
		t.Fatalf("read wrong number of bytes from %v: want %v, got %v", filename, m, n)
	}

	if err = f.Close(); err != nil {
		t.Fatal(err)
	}

	h := restic.Handle{Type: restic.DataFile, Name: restic.Hash(data).String()}

	err = be.Save(h, data)
	if err != nil {
		t.Fatal(err)
	}

	err = os.Remove(filename)
	if err != nil {
		t.Fatal(err)
	}
}

func TestSaveFrom(t *testing.T) {
	repo, cleanup := repository.TestRepository(t)
	defer cleanup()

	for _, size := range testSizes {
		data := make([]byte, size)
		_, err := io.ReadFull(rand.Reader, data)
		OK(t, err)

		id := restic.Hash(data)

		// save
		id2, err := repo.SaveBlob(restic.DataBlob, data, id)
		OK(t, err)
		Equals(t, id, id2)

		OK(t, repo.Flush())

		// read back
		buf := make([]byte, size)
		n, err := repo.LoadBlob(restic.DataBlob, id, buf)
		OK(t, err)
		Equals(t, len(buf), n)

		Assert(t, len(buf) == len(data),
			"number of bytes read back does not match: expected %d, got %d",
			len(data), len(buf))

		Assert(t, bytes.Equal(buf, data),
			"data does not match: expected %02x, got %02x",
			data, buf)
	}
}

// savePacker stores p in the backend.
func (r *Repository) savePacker(p *pack.Packer) error {
	debug.Log("save packer with %d blobs\n", p.Count())
	n, err := p.Finalize()
	if err != nil {
		return err
	}

	tmpfile := p.Writer().(*os.File)
	f, err := fs.Open(tmpfile.Name())
	if err != nil {
		return errors.Wrap(err, "Open")
	}

	data := make([]byte, n)
	m, err := io.ReadFull(f, data)
	if err != nil {
		return errors.Wrap(err, "ReadFul")
	}

	if uint(m) != n {
		return errors.Errorf("read wrong number of bytes from %v: want %v, got %v", tmpfile.Name(), n, m)
	}

	if err = f.Close(); err != nil {
		return errors.Wrap(err, "Close")
	}

	id := restic.Hash(data)
	h := restic.Handle{Type: restic.DataFile, Name: id.String()}

	err = r.be.Save(h, data)
	if err != nil {
		debug.Log("Save(%v) error: %v", h, err)
		return err
	}

	debug.Log("saved as %v", h)

	err = fs.Remove(tmpfile.Name())
	if err != nil {
		return errors.Wrap(err, "Remove")
	}

	// update blobs in the index
	for _, b := range p.Blobs() {
		debug.Log("  updating blob %v to pack %v", b.ID.Str(), id.Str())
		r.idx.Current().Store(restic.PackedBlob{
			Blob: restic.Blob{
				Type:   b.Type,
				ID:     b.ID,
				Offset: b.Offset,
				Length: uint(b.Length),
			},
			PackID: id,
		})
	}

	return nil
}

// checkPack reads a pack and checks the integrity of all blobs.
func checkPack(r restic.Repository, id restic.ID) error {
	debug.Log("checking pack %v", id.Str())
	h := restic.Handle{Type: restic.DataFile, Name: id.String()}
	buf, err := backend.LoadAll(r.Backend(), h, nil)
	if err != nil {
		return err
	}

	hash := restic.Hash(buf)
	if !hash.Equal(id) {
		debug.Log("Pack ID does not match, want %v, got %v", id.Str(), hash.Str())
		return errors.Errorf("Pack ID does not match, want %v, got %v", id.Str(), hash.Str())
	}

	blobs, err := pack.List(r.Key(), bytes.NewReader(buf), int64(len(buf)))
	if err != nil {
		return err
	}

	var errs []error
	for i, blob := range blobs {
		debug.Log("  check blob %d: %v", i, blob.ID.Str())

		plainBuf := make([]byte, blob.Length)
		n, err := crypto.Decrypt(r.Key(), plainBuf, buf[blob.Offset:blob.Offset+blob.Length])
		if err != nil {
			debug.Log("  error decrypting blob %v: %v", blob.ID.Str(), err)
			errs = append(errs, errors.Errorf("blob %v: %v", i, err))
			continue
		}
		plainBuf = plainBuf[:n]

		hash := restic.Hash(plainBuf)
		if !hash.Equal(blob.ID) {
			debug.Log("  Blob ID does not match, want %v, got %v", blob.ID.Str(), hash.Str())
			errs = append(errs, errors.Errorf("Blob ID does not match, want %v, got %v", blob.ID.Str(), hash.Str()))
			continue
		}
	}

	if len(errs) > 0 {
		return errors.Errorf("pack %v contains %v errors: %v", id.Str(), len(errs), errs)
	}

	return nil
}

// TestLoadNegativeOffset tests the backend's Load function with negative offsets.
func TestLoadNegativeOffset(t testing.TB) {
	b := open(t)
	defer close(t)

	length := rand.Intn(1<<24) + 2000

	data := test.Random(23, length)
	id := restic.Hash(data)

	handle := restic.Handle{Type: restic.DataFile, Name: id.String()}
	err := b.Save(handle, data)
	if err != nil {
		t.Fatalf("Save() error: %v", err)
	}

	// test normal reads
	for i := 0; i < 50; i++ {
		l := rand.Intn(length + 2000)
		o := -rand.Intn(length + 2000)

		buf := make([]byte, l)
		n, err := b.Load(handle, buf, int64(o))

		// if we requested data beyond the end of the file, require
		// ErrUnexpectedEOF error
		if len(buf) > -o {
			if errors.Cause(err) != io.ErrUnexpectedEOF {
				t.Errorf("Load(%d, %d) did not return io.ErrUnexpectedEOF", len(buf), o)
				continue
			}
			err = nil
			buf = buf[:-o]
		}

		if err != nil {
			t.Errorf("Load(%d, %d) returned error: %v", len(buf), o, err)
			continue
		}

		if n != len(buf) {
			t.Errorf("Load(%d, %d) returned short read, only got %d bytes", len(buf), o, n)
			continue
		}

		p := len(data) + o
		if !bytes.Equal(buf, data[p:p+len(buf)]) {
			t.Errorf("Load(%d, %d) returned wrong bytes", len(buf), o)
			continue
		}

	}

	test.OK(t, b.Remove(restic.DataFile, id.String()))
}

func genTestContent() map[restic.ID][]byte {
	m := make(map[restic.ID][]byte)

	for _, length := range testContentLengths {
		buf := Random(int(length), int(length))
		id := restic.Hash(buf)
		m[id] = buf
		testMaxFileSize += length
	}

	return m
}

func TestShortPack(t *testing.T) {
	k := crypto.NewRandomKey()

	bufs, packData, packSize := newPack(t, k, []int{23})

	b := mem.New()
	id := restic.Hash(packData)

	handle := restic.Handle{Type: restic.DataFile, Name: id.String()}
	OK(t, b.Save(handle, packData))
	verifyBlobs(t, bufs, k, restic.ReaderAt(b, handle), packSize)
}

func TestUnpackReadSeeker(t *testing.T) {
	// create random keys
	k := crypto.NewRandomKey()

	bufs, packData, packSize := newPack(t, k, testLens)

	b := mem.New()
	id := restic.Hash(packData)

	handle := restic.Handle{Type: restic.DataFile, Name: id.String()}
	OK(t, b.Save(handle, packData))
	verifyBlobs(t, bufs, k, restic.ReaderAt(b, handle), packSize)
}

func (arch *Archiver) saveChunk(chunk chunker.Chunk, p *restic.Progress, token struct{}, file fs.File, resultChannel chan<- saveResult) {
	defer freeBuf(chunk.Data)

	id := restic.Hash(chunk.Data)
	err := arch.Save(restic.DataBlob, chunk.Data, id)
	// TODO handle error
	if err != nil {
		panic(err)
	}

	p.Report(restic.Stat{Bytes: uint64(chunk.Length)})
	arch.blobToken <- token
	resultChannel <- saveResult{id: id, bytes: uint64(chunk.Length)}
}

// SaveTreeJSON stores a tree in the repository.
func (arch *Archiver) SaveTreeJSON(tree *restic.Tree) (restic.ID, error) {
	data, err := json.Marshal(tree)
	if err != nil {
		return restic.ID{}, errors.Wrap(err, "Marshal")
	}
	data = append(data, '\n')

	// check if tree has been saved before
	id := restic.Hash(data)
	if arch.isKnownBlob(id, restic.TreeBlob) {
		return id, nil
	}

	return arch.repo.SaveBlob(restic.TreeBlob, data, id)
}

// SaveTree stores a tree into the repository and returns the ID. The ID is
// checked against the index. The tree is only stored when the index does not
// contain the ID.
func (r *Repository) SaveTree(t *restic.Tree) (restic.ID, error) {
	buf, err := json.Marshal(t)
	if err != nil {
		return restic.ID{}, errors.Wrap(err, "MarshalJSON")
	}

	// append a newline so that the data is always consistent (json.Encoder
	// adds a newline after each object)
	buf = append(buf, '\n')

	id := restic.Hash(buf)
	if r.idx.Has(id, restic.TreeBlob) {
		return id, nil
	}

	_, err = r.SaveBlob(restic.TreeBlob, buf, id)
	return id, err
}

// SaveUnpacked encrypts data and stores it in the backend. Returned is the
// storage hash.
func (r *Repository) SaveUnpacked(t restic.FileType, p []byte) (id restic.ID, err error) {
	ciphertext := make([]byte, len(p)+crypto.Extension)
	ciphertext, err = r.Encrypt(ciphertext, p)
	if err != nil {
		return restic.ID{}, err
	}

	id = restic.Hash(ciphertext)
	h := restic.Handle{Type: t, Name: id.String()}

	err = r.be.Save(h, ciphertext)
	if err != nil {
		debug.Log("error saving blob %v: %v", h, err)
		return restic.ID{}, err
	}

	debug.Log("blob %v saved", h)
	return id, nil
}

func testParallelSaveWithDuplication(t *testing.T, seed int) {
	repo, cleanup := repository.TestRepository(t)
	defer cleanup()

	dataSizeMb := 128
	duplication := 7

	arch := archiver.New(repo)
	chunks := getRandomData(seed, dataSizeMb*1024*1024)

	errChannels := [](<-chan error){}

	// interweaved processing of subsequent chunks
	maxParallel := 2*duplication - 1
	barrier := make(chan struct{}, maxParallel)

	for _, c := range chunks {
		for dupIdx := 0; dupIdx < duplication; dupIdx++ {
			errChan := make(chan error)
			errChannels = append(errChannels, errChan)

			go func(c chunker.Chunk, errChan chan<- error) {
				barrier <- struct{}{}

				id := restic.Hash(c.Data)
				time.Sleep(time.Duration(id[0]))
				err := arch.Save(restic.DataBlob, c.Data, id)
				<-barrier
				errChan <- err
			}(c, errChan)
		}
	}

	for _, errChan := range errChannels {
		OK(t, <-errChan)
	}

	OK(t, repo.Flush())
	OK(t, repo.SaveIndex())

	chkr := createAndInitChecker(t, repo)
	assertNoUnreferencedPacks(t, chkr)
}

// SaveAndEncrypt encrypts data and stores it to the backend as type t. If data
// is small enough, it will be packed together with other small blobs.
func (r *Repository) SaveAndEncrypt(t restic.BlobType, data []byte, id *restic.ID) (restic.ID, error) {
	if id == nil {
		// compute plaintext hash
		hashedID := restic.Hash(data)
		id = &hashedID
	}

	debug.Log("save id %v (%v, %d bytes)", id.Str(), t, len(data))

	// get buf from the pool
	ciphertext := getBuf()
	defer freeBuf(ciphertext)

	// encrypt blob
	ciphertext, err := r.Encrypt(ciphertext, data)
	if err != nil {
		return restic.ID{}, err
	}

	// find suitable packer and add blob
	packer, err := r.findPacker(uint(len(ciphertext)))
	if err != nil {
		return restic.ID{}, err
	}

	// save ciphertext
	_, err = packer.Add(t, *id, ciphertext)
	if err != nil {
		return restic.ID{}, err
	}

	// if the pack is not full enough and there are less than maxPackers
	// packers, put back to the list
	if packer.Size() < minPackSize && r.countPacker() < maxPackers {
		debug.Log("pack is not full enough (%d bytes)", packer.Size())
		r.insertPacker(packer)
		return *id, nil
	}

	// else write the pack to the backend
	return *id, r.savePacker(packer)
}