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authorAntonio Jesus Navarro Perez <antnavper@gmail.com>2018-06-05 18:33:27 +0200
committerAntonio Jesus Navarro Perez <antnavper@gmail.com>2018-06-05 18:34:08 +0200
commitb0d807a1ae0687ef3a01d78c1dc5e55f7217268f (patch)
tree3a9d6f21cad1af18d940abcc17ddb1337e78146d /storage/filesystem/internal/dotgit/writers.go
parent8955f060a3cba36a56ac334576eba4123f6e918a (diff)
downloadgo-git-b0d807a1ae0687ef3a01d78c1dc5e55f7217268f.tar.gz
dotgit: Move package outside internal.
Signed-off-by: Antonio Jesus Navarro Perez <antnavper@gmail.com>
Diffstat (limited to 'storage/filesystem/internal/dotgit/writers.go')
-rw-r--r--storage/filesystem/internal/dotgit/writers.go282
1 files changed, 0 insertions, 282 deletions
diff --git a/storage/filesystem/internal/dotgit/writers.go b/storage/filesystem/internal/dotgit/writers.go
deleted file mode 100644
index c2b420f..0000000
--- a/storage/filesystem/internal/dotgit/writers.go
+++ /dev/null
@@ -1,282 +0,0 @@
-package dotgit
-
-import (
- "fmt"
- "io"
- "sync/atomic"
-
- "gopkg.in/src-d/go-git.v4/plumbing"
- "gopkg.in/src-d/go-git.v4/plumbing/format/idxfile"
- "gopkg.in/src-d/go-git.v4/plumbing/format/objfile"
- "gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
-
- "gopkg.in/src-d/go-billy.v4"
-)
-
-// PackWriter is a io.Writer that generates the packfile index simultaneously,
-// a packfile.Decoder is used with a file reader to read the file being written
-// this operation is synchronized with the write operations.
-// The packfile is written in a temp file, when Close is called this file
-// is renamed/moved (depends on the Filesystem implementation) to the final
-// location, if the PackWriter is not used, nothing is written
-type PackWriter struct {
- Notify func(plumbing.Hash, *packfile.Index)
-
- fs billy.Filesystem
- fr, fw billy.File
- synced *syncedReader
- checksum plumbing.Hash
- index *packfile.Index
- result chan error
-}
-
-func newPackWrite(fs billy.Filesystem) (*PackWriter, error) {
- fw, err := fs.TempFile(fs.Join(objectsPath, packPath), "tmp_pack_")
- if err != nil {
- return nil, err
- }
-
- fr, err := fs.Open(fw.Name())
- if err != nil {
- return nil, err
- }
-
- writer := &PackWriter{
- fs: fs,
- fw: fw,
- fr: fr,
- synced: newSyncedReader(fw, fr),
- result: make(chan error),
- }
-
- go writer.buildIndex()
- return writer, nil
-}
-
-func (w *PackWriter) buildIndex() {
- s := packfile.NewScanner(w.synced)
- d, err := packfile.NewDecoder(s, nil)
- if err != nil {
- w.result <- err
- return
- }
-
- checksum, err := d.Decode()
- if err != nil {
- w.result <- err
- return
- }
-
- w.checksum = checksum
- w.index = d.Index()
- w.result <- err
-}
-
-// waitBuildIndex waits until buildIndex function finishes, this can terminate
-// with a packfile.ErrEmptyPackfile, this means that nothing was written so we
-// ignore the error
-func (w *PackWriter) waitBuildIndex() error {
- err := <-w.result
- if err == packfile.ErrEmptyPackfile {
- return nil
- }
-
- return err
-}
-
-func (w *PackWriter) Write(p []byte) (int, error) {
- return w.synced.Write(p)
-}
-
-// Close closes all the file descriptors and save the final packfile, if nothing
-// was written, the tempfiles are deleted without writing a packfile.
-func (w *PackWriter) Close() error {
- defer func() {
- if w.Notify != nil && w.index != nil && w.index.Size() > 0 {
- w.Notify(w.checksum, w.index)
- }
-
- close(w.result)
- }()
-
- if err := w.synced.Close(); err != nil {
- return err
- }
-
- if err := w.waitBuildIndex(); err != nil {
- return err
- }
-
- if err := w.fr.Close(); err != nil {
- return err
- }
-
- if err := w.fw.Close(); err != nil {
- return err
- }
-
- if w.index == nil || w.index.Size() == 0 {
- return w.clean()
- }
-
- return w.save()
-}
-
-func (w *PackWriter) clean() error {
- return w.fs.Remove(w.fw.Name())
-}
-
-func (w *PackWriter) save() error {
- base := w.fs.Join(objectsPath, packPath, fmt.Sprintf("pack-%s", w.checksum))
- idx, err := w.fs.Create(fmt.Sprintf("%s.idx", base))
- if err != nil {
- return err
- }
-
- if err := w.encodeIdx(idx); err != nil {
- return err
- }
-
- if err := idx.Close(); err != nil {
- return err
- }
-
- return w.fs.Rename(w.fw.Name(), fmt.Sprintf("%s.pack", base))
-}
-
-func (w *PackWriter) encodeIdx(writer io.Writer) error {
- idx := w.index.ToIdxFile()
- idx.PackfileChecksum = w.checksum
- idx.Version = idxfile.VersionSupported
- e := idxfile.NewEncoder(writer)
- _, err := e.Encode(idx)
- return err
-}
-
-type syncedReader struct {
- w io.Writer
- r io.ReadSeeker
-
- blocked, done uint32
- written, read uint64
- news chan bool
-}
-
-func newSyncedReader(w io.Writer, r io.ReadSeeker) *syncedReader {
- return &syncedReader{
- w: w,
- r: r,
- news: make(chan bool),
- }
-}
-
-func (s *syncedReader) Write(p []byte) (n int, err error) {
- defer func() {
- written := atomic.AddUint64(&s.written, uint64(n))
- read := atomic.LoadUint64(&s.read)
- if written > read {
- s.wake()
- }
- }()
-
- n, err = s.w.Write(p)
- return
-}
-
-func (s *syncedReader) Read(p []byte) (n int, err error) {
- defer func() { atomic.AddUint64(&s.read, uint64(n)) }()
-
- for {
- s.sleep()
- n, err = s.r.Read(p)
- if err == io.EOF && !s.isDone() && n == 0 {
- continue
- }
-
- break
- }
-
- return
-}
-
-func (s *syncedReader) isDone() bool {
- return atomic.LoadUint32(&s.done) == 1
-}
-
-func (s *syncedReader) isBlocked() bool {
- return atomic.LoadUint32(&s.blocked) == 1
-}
-
-func (s *syncedReader) wake() {
- if s.isBlocked() {
- // fmt.Println("wake")
- atomic.StoreUint32(&s.blocked, 0)
- s.news <- true
- }
-}
-
-func (s *syncedReader) sleep() {
- read := atomic.LoadUint64(&s.read)
- written := atomic.LoadUint64(&s.written)
- if read >= written {
- atomic.StoreUint32(&s.blocked, 1)
- // fmt.Println("sleep", read, written)
- <-s.news
- }
-
-}
-
-func (s *syncedReader) Seek(offset int64, whence int) (int64, error) {
- if whence == io.SeekCurrent {
- return s.r.Seek(offset, whence)
- }
-
- p, err := s.r.Seek(offset, whence)
- atomic.StoreUint64(&s.read, uint64(p))
-
- return p, err
-}
-
-func (s *syncedReader) Close() error {
- atomic.StoreUint32(&s.done, 1)
- close(s.news)
- return nil
-}
-
-type ObjectWriter struct {
- objfile.Writer
- fs billy.Filesystem
- f billy.File
-}
-
-func newObjectWriter(fs billy.Filesystem) (*ObjectWriter, error) {
- f, err := fs.TempFile(fs.Join(objectsPath, packPath), "tmp_obj_")
- if err != nil {
- return nil, err
- }
-
- return &ObjectWriter{
- Writer: (*objfile.NewWriter(f)),
- fs: fs,
- f: f,
- }, nil
-}
-
-func (w *ObjectWriter) Close() error {
- if err := w.Writer.Close(); err != nil {
- return err
- }
-
- if err := w.f.Close(); err != nil {
- return err
- }
-
- return w.save()
-}
-
-func (w *ObjectWriter) save() error {
- hash := w.Hash().String()
- file := w.fs.Join(objectsPath, hash[0:2], hash[2:40])
-
- return w.fs.Rename(w.f.Name(), file)
-}