| package utils |
| |
| import ( |
| "bytes" |
| "compress/gzip" |
| "crypto/sha256" |
| "encoding/hex" |
| "github.com/dotcloud/tar" |
| "hash" |
| "io" |
| "sort" |
| "strconv" |
| ) |
| |
| type verboseHash struct { |
| hash.Hash |
| } |
| |
| func (h verboseHash) Write(buf []byte) (int, error) { |
| Debugf("--->%s<---", buf) |
| return h.Hash.Write(buf) |
| } |
| |
| type TarSum struct { |
| io.Reader |
| tarR *tar.Reader |
| tarW *tar.Writer |
| gz *gzip.Writer |
| bufTar *bytes.Buffer |
| bufGz *bytes.Buffer |
| h hash.Hash |
| h2 verboseHash |
| sums []string |
| finished bool |
| first bool |
| } |
| |
| func (ts *TarSum) encodeHeader(h *tar.Header) error { |
| for _, elem := range [][2]string{ |
| {"name", h.Name}, |
| {"mode", strconv.Itoa(int(h.Mode))}, |
| {"uid", strconv.Itoa(h.Uid)}, |
| {"gid", strconv.Itoa(h.Gid)}, |
| {"size", strconv.Itoa(int(h.Size))}, |
| {"mtime", strconv.Itoa(int(h.ModTime.UTC().Unix()))}, |
| {"typeflag", string([]byte{h.Typeflag})}, |
| {"linkname", h.Linkname}, |
| {"uname", h.Uname}, |
| {"gname", h.Gname}, |
| {"devmajor", strconv.Itoa(int(h.Devmajor))}, |
| {"devminor", strconv.Itoa(int(h.Devminor))}, |
| // {"atime", strconv.Itoa(int(h.AccessTime.UTC().Unix()))}, |
| // {"ctime", strconv.Itoa(int(h.ChangeTime.UTC().Unix()))}, |
| } { |
| // Debugf("-->%s<-- -->%s<--", elem[0], elem[1]) |
| if _, err := ts.h.Write([]byte(elem[0] + elem[1])); err != nil { |
| return err |
| } |
| } |
| return nil |
| } |
| |
| func (ts *TarSum) Read(buf []byte) (int, error) { |
| if ts.gz == nil { |
| ts.bufTar = bytes.NewBuffer([]byte{}) |
| ts.bufGz = bytes.NewBuffer([]byte{}) |
| ts.tarR = tar.NewReader(ts.Reader) |
| ts.tarW = tar.NewWriter(ts.bufTar) |
| ts.gz = gzip.NewWriter(ts.bufGz) |
| ts.h = sha256.New() |
| // ts.h = verboseHash{sha256.New()} |
| ts.h.Reset() |
| ts.first = true |
| } |
| |
| if ts.finished { |
| return ts.bufGz.Read(buf) |
| } |
| buf2 := make([]byte, len(buf), cap(buf)) |
| |
| n, err := ts.tarR.Read(buf2) |
| if err != nil { |
| if err == io.EOF { |
| if _, err := ts.h.Write(buf2[:n]); err != nil { |
| return 0, err |
| } |
| if !ts.first { |
| ts.sums = append(ts.sums, hex.EncodeToString(ts.h.Sum(nil))) |
| ts.h.Reset() |
| } else { |
| ts.first = false |
| } |
| |
| currentHeader, err := ts.tarR.Next() |
| if err != nil { |
| if err == io.EOF { |
| if err := ts.gz.Close(); err != nil { |
| return 0, err |
| } |
| ts.finished = true |
| return n, nil |
| } |
| return n, err |
| } |
| if err := ts.encodeHeader(currentHeader); err != nil { |
| return 0, err |
| } |
| if err := ts.tarW.WriteHeader(currentHeader); err != nil { |
| return 0, err |
| } |
| if _, err := ts.tarW.Write(buf2[:n]); err != nil { |
| return 0, err |
| } |
| ts.tarW.Flush() |
| if _, err := io.Copy(ts.gz, ts.bufTar); err != nil { |
| return 0, err |
| } |
| ts.gz.Flush() |
| |
| return ts.bufGz.Read(buf) |
| } |
| return n, err |
| } |
| |
| // Filling the hash buffer |
| if _, err = ts.h.Write(buf2[:n]); err != nil { |
| return 0, err |
| } |
| |
| // Filling the tar writter |
| if _, err = ts.tarW.Write(buf2[:n]); err != nil { |
| return 0, err |
| } |
| ts.tarW.Flush() |
| |
| // Filling the gz writter |
| if _, err = io.Copy(ts.gz, ts.bufTar); err != nil { |
| return 0, err |
| } |
| ts.gz.Flush() |
| |
| return ts.bufGz.Read(buf) |
| } |
| |
| func (ts *TarSum) Sum(extra []byte) string { |
| sort.Strings(ts.sums) |
| h := sha256.New() |
| if extra != nil { |
| h.Write(extra) |
| } |
| for _, sum := range ts.sums { |
| Debugf("-->%s<--", sum) |
| h.Write([]byte(sum)) |
| } |
| checksum := "tarsum+sha256:" + hex.EncodeToString(h.Sum(nil)) |
| Debugf("checksum processed: %s", checksum) |
| return checksum |
| } |