Remove zlib compression

This commit is contained in:
Alexander Neumann 2015-03-02 09:56:56 +01:00
parent b4cb75693e
commit c056382c9c
2 changed files with 6 additions and 61 deletions

View file

@ -113,10 +113,10 @@ Snapshots
A snapshots represents a directory with all files and sub-directories at a
given point in time. For each backup that is made, a new snapshot is created. A
snapshot is a zlib-compressed JSON document that is stored in an encrypted file
below the directory `snapshots` in the repository. The filename is the SHA-256
hash of the (encrypted) contents. This string is unique and used within restic
to uniquely identify a snapshot.
snapshot is a JSON document that is stored in an encrypted file below the
directory `snapshots` in the repository. The filename is the SHA-256 hash of
the (encrypted) contents. This string is unique and used within restic to
uniquely identify a snapshot.
The command `restic cat snapshot` can be used as follows to decrypt and
pretty-print the contents of a snapshot file:

View file

@ -1,9 +1,6 @@
package restic
import (
"bytes"
"compress/flate"
"compress/zlib"
"crypto/sha256"
"encoding/json"
"errors"
@ -109,26 +106,6 @@ func (s Server) LoadJSON(t backend.Type, blob Blob, item interface{}) error {
return s.LoadJSONID(t, blob.Storage, item)
}
var (
zEmptyString = []byte("x\x9C\x03\x00\x00\x00\x00\x01")
)
var zReaderPool = sync.Pool{
New: func() interface{} {
rd, err := zlib.NewReader(bytes.NewReader(zEmptyString))
if err != nil {
// shouldn't happen
panic(err)
}
return rd
},
}
type zReader interface {
io.ReadCloser
zlib.Resetter
}
// LoadJSONID calls Load() to get content from the backend and afterwards calls
// json.Unmarshal on the item.
func (s Server) LoadJSONID(t backend.Type, storageID backend.ID, item interface{}) error {
@ -146,21 +123,8 @@ func (s Server) LoadJSONID(t backend.Type, storageID backend.ID, item interface{
return err
}
// unzip
br := decryptRd.(flate.Reader)
unzipRd := zReaderPool.Get().(zReader)
err = unzipRd.Reset(br, nil)
defer func() {
unzipRd.Close()
zReaderPool.Put(unzipRd)
}()
if err != nil {
return err
}
// decode
decoder := json.NewDecoder(unzipRd)
decoder := json.NewDecoder(decryptRd)
err = decoder.Decode(item)
if err != nil {
return err
@ -275,12 +239,6 @@ func (s Server) SaveFrom(t backend.Type, id backend.ID, length uint, rd io.Reade
}, nil
}
var zWriterPool = sync.Pool{
New: func() interface{} {
return zlib.NewWriter(nil)
},
}
// SaveJSON serialises item as JSON and encrypts and saves it in the backend as
// type t.
func (s Server) SaveJSON(t backend.Type, item interface{}) (Blob, error) {
@ -290,14 +248,7 @@ func (s Server) SaveJSON(t backend.Type, item interface{}) (Blob, error) {
}
encWr := s.key.EncryptTo(backendBlob)
wr := zWriterPool.Get().(*zlib.Writer)
defer zWriterPool.Put(wr)
wr.Reset(encWr)
if err != nil {
return Blob{}, fmt.Errorf("zlib.NewWriter: %v", err)
}
hw := backend.NewHashingWriter(wr, sha256.New())
hw := backend.NewHashingWriter(encWr, sha256.New())
enc := json.NewEncoder(hw)
err = enc.Encode(item)
@ -305,12 +256,6 @@ func (s Server) SaveJSON(t backend.Type, item interface{}) (Blob, error) {
return Blob{}, fmt.Errorf("json.NewEncoder: %v", err)
}
// flush zlib writer
err = wr.Close()
if err != nil {
return Blob{}, fmt.Errorf("zlib.Writer.Close(): %v", err)
}
// finish encryption
err = encWr.Close()
if err != nil {