mirror of
https://github.com/octoleo/restic.git
synced 2024-11-21 20:35:12 +00:00
repository: split StreamPack implementation
Move the actual decoding of the pack data into a separate iterator.
This commit is contained in:
Michael Eischer
parent
54c5c72e5a
commit
fb422497af
@ -882,7 +882,7 @@ const maxUnusedRange = 4 * 1024 * 1024
|
||||
|
||||
// StreamPack loads the listed blobs from the specified pack file. The plaintext blob is passed to
|
||||
// the handleBlobFn callback or an error if decryption failed or the blob hash does not match.
|
||||
// handleBlobFn is never called multiple times for the same blob. If the callback returns an error,
|
||||
// handleBlobFn is called at most once for each blob. If the callback returns an error,
|
||||
// then StreamPack will abort and not retry it.
|
||||
func StreamPack(ctx context.Context, beLoad BackendLoadFn, key *crypto.Key, packID restic.ID, blobs []restic.Blob, handleBlobFn func(blob restic.BlobHandle, buf []byte, err error) error) error {
|
||||
if len(blobs) == 0 {
|
||||
@ -940,72 +940,18 @@ func streamPackPart(ctx context.Context, beLoad BackendLoadFn, key *crypto.Key,
|
||||
if bufferSize > MaxStreamBufferSize {
|
||||
bufferSize = MaxStreamBufferSize
|
||||
}
|
||||
// create reader here to allow reusing the buffered reader from checker.checkData
|
||||
bufRd := bufio.NewReaderSize(rd, bufferSize)
|
||||
currentBlobEnd := dataStart
|
||||
var buf []byte
|
||||
var decode []byte
|
||||
for len(blobs) > 0 {
|
||||
entry := blobs[0]
|
||||
it := NewPackBlobIterator(packID, bufRd, dataStart, blobs, key, dec)
|
||||
|
||||
skipBytes := int(entry.Offset - currentBlobEnd)
|
||||
if skipBytes < 0 {
|
||||
return errors.Errorf("overlapping blobs in pack %v", packID)
|
||||
}
|
||||
|
||||
_, err := bufRd.Discard(skipBytes)
|
||||
if err != nil {
|
||||
for {
|
||||
val, err := it.Next()
|
||||
if err == ErrPackEOF {
|
||||
break
|
||||
} else if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
h := restic.BlobHandle{ID: entry.ID, Type: entry.Type}
|
||||
debug.Log(" process blob %v, skipped %d, %v", h, skipBytes, entry)
|
||||
|
||||
if uint(cap(buf)) < entry.Length {
|
||||
buf = make([]byte, entry.Length)
|
||||
}
|
||||
buf = buf[:entry.Length]
|
||||
|
||||
n, err := io.ReadFull(bufRd, buf)
|
||||
if err != nil {
|
||||
debug.Log(" read error %v", err)
|
||||
return errors.Wrap(err, "ReadFull")
|
||||
}
|
||||
|
||||
if n != len(buf) {
|
||||
return errors.Errorf("read blob %v from %v: not enough bytes read, want %v, got %v",
|
||||
h, packID.Str(), len(buf), n)
|
||||
}
|
||||
currentBlobEnd = entry.Offset + entry.Length
|
||||
|
||||
if int(entry.Length) <= key.NonceSize() {
|
||||
debug.Log("%v", blobs)
|
||||
return errors.Errorf("invalid blob length %v", entry)
|
||||
}
|
||||
|
||||
// decryption errors are likely permanent, give the caller a chance to skip them
|
||||
nonce, ciphertext := buf[:key.NonceSize()], buf[key.NonceSize():]
|
||||
plaintext, err := key.Open(ciphertext[:0], nonce, ciphertext, nil)
|
||||
if err == nil && entry.IsCompressed() {
|
||||
// DecodeAll will allocate a slice if it is not large enough since it
|
||||
// knows the decompressed size (because we're using EncodeAll)
|
||||
decode, err = dec.DecodeAll(plaintext, decode[:0])
|
||||
plaintext = decode
|
||||
if err != nil {
|
||||
err = errors.Errorf("decompressing blob %v failed: %v", h, err)
|
||||
}
|
||||
}
|
||||
if err == nil {
|
||||
id := restic.Hash(plaintext)
|
||||
if !id.Equal(entry.ID) {
|
||||
debug.Log("read blob %v/%v from %v: wrong data returned, hash is %v",
|
||||
h.Type, h.ID, packID.Str(), id)
|
||||
err = errors.Errorf("read blob %v from %v: wrong data returned, hash is %v",
|
||||
h, packID.Str(), id)
|
||||
}
|
||||
}
|
||||
|
||||
err = handleBlobFn(entry.BlobHandle, plaintext, err)
|
||||
err = handleBlobFn(val.Handle, val.Plaintext, val.Err)
|
||||
if err != nil {
|
||||
cancel()
|
||||
return backoff.Permanent(err)
|
||||
@ -1018,6 +964,109 @@ func streamPackPart(ctx context.Context, beLoad BackendLoadFn, key *crypto.Key,
|
||||
return errors.Wrap(err, "StreamPack")
|
||||
}
|
||||
|
||||
type PackBlobIterator struct {
|
||||
packID restic.ID
|
||||
rd *bufio.Reader
|
||||
currentOffset uint
|
||||
|
||||
blobs []restic.Blob
|
||||
key *crypto.Key
|
||||
dec *zstd.Decoder
|
||||
|
||||
buf []byte
|
||||
decode []byte
|
||||
}
|
||||
|
||||
type PackBlobValue struct {
|
||||
Handle restic.BlobHandle
|
||||
Plaintext []byte
|
||||
Err error
|
||||
}
|
||||
|
||||
var ErrPackEOF = errors.New("reached EOF of pack file")
|
||||
|
||||
func NewPackBlobIterator(packID restic.ID, rd *bufio.Reader, currentOffset uint,
|
||||
blobs []restic.Blob, key *crypto.Key, dec *zstd.Decoder) *PackBlobIterator {
|
||||
return &PackBlobIterator{
|
||||
packID: packID,
|
||||
rd: rd,
|
||||
currentOffset: currentOffset,
|
||||
blobs: blobs,
|
||||
key: key,
|
||||
dec: dec,
|
||||
}
|
||||
}
|
||||
|
||||
// Next returns the next blob, an error or ErrPackEOF if all blobs were read
|
||||
func (b *PackBlobIterator) Next() (PackBlobValue, error) {
|
||||
if len(b.blobs) == 0 {
|
||||
return PackBlobValue{}, ErrPackEOF
|
||||
}
|
||||
|
||||
entry := b.blobs[0]
|
||||
b.blobs = b.blobs[1:]
|
||||
|
||||
skipBytes := int(entry.Offset - b.currentOffset)
|
||||
if skipBytes < 0 {
|
||||
return PackBlobValue{}, errors.Errorf("overlapping blobs in pack %v", b.packID)
|
||||
}
|
||||
|
||||
_, err := b.rd.Discard(skipBytes)
|
||||
if err != nil {
|
||||
return PackBlobValue{}, err
|
||||
}
|
||||
b.currentOffset = entry.Offset
|
||||
|
||||
h := restic.BlobHandle{ID: entry.ID, Type: entry.Type}
|
||||
debug.Log(" process blob %v, skipped %d, %v", h, skipBytes, entry)
|
||||
|
||||
if uint(cap(b.buf)) < entry.Length {
|
||||
b.buf = make([]byte, entry.Length)
|
||||
}
|
||||
b.buf = b.buf[:entry.Length]
|
||||
|
||||
n, err := io.ReadFull(b.rd, b.buf)
|
||||
if err != nil {
|
||||
debug.Log(" read error %v", err)
|
||||
return PackBlobValue{}, errors.Wrap(err, "ReadFull")
|
||||
}
|
||||
|
||||
if n != len(b.buf) {
|
||||
return PackBlobValue{}, errors.Errorf("read blob %v from %v: not enough bytes read, want %v, got %v",
|
||||
h, b.packID.Str(), len(b.buf), n)
|
||||
}
|
||||
b.currentOffset = entry.Offset + entry.Length
|
||||
|
||||
if int(entry.Length) <= b.key.NonceSize() {
|
||||
debug.Log("%v", b.blobs)
|
||||
return PackBlobValue{}, errors.Errorf("invalid blob length %v", entry)
|
||||
}
|
||||
|
||||
// decryption errors are likely permanent, give the caller a chance to skip them
|
||||
nonce, ciphertext := b.buf[:b.key.NonceSize()], b.buf[b.key.NonceSize():]
|
||||
plaintext, err := b.key.Open(ciphertext[:0], nonce, ciphertext, nil)
|
||||
if err == nil && entry.IsCompressed() {
|
||||
// DecodeAll will allocate a slice if it is not large enough since it
|
||||
// knows the decompressed size (because we're using EncodeAll)
|
||||
b.decode, err = b.dec.DecodeAll(plaintext, b.decode[:0])
|
||||
plaintext = b.decode
|
||||
if err != nil {
|
||||
err = errors.Errorf("decompressing blob %v failed: %v", h, err)
|
||||
}
|
||||
}
|
||||
if err == nil {
|
||||
id := restic.Hash(plaintext)
|
||||
if !id.Equal(entry.ID) {
|
||||
debug.Log("read blob %v/%v from %v: wrong data returned, hash is %v",
|
||||
h.Type, h.ID, b.packID.Str(), id)
|
||||
err = errors.Errorf("read blob %v from %v: wrong data returned, hash is %v",
|
||||
h, b.packID.Str(), id)
|
||||
}
|
||||
}
|
||||
|
||||
return PackBlobValue{entry.BlobHandle, plaintext, err}, nil
|
||||
}
|
||||
|
||||
var zeroChunkOnce sync.Once
|
||||
var zeroChunkID restic.ID
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user