gogit.go

  1package repository
  2
  3import (
  4	"bufio"
  5	"bytes"
  6	"errors"
  7	"fmt"
  8	"io"
  9	"os"
 10	"path/filepath"
 11	"sort"
 12	"strings"
 13	"sync"
 14	"time"
 15
 16	"github.com/ProtonMail/go-crypto/openpgp"
 17	"github.com/go-git/go-billy/v5/osfs"
 18	gogit "github.com/go-git/go-git/v5"
 19	"github.com/go-git/go-git/v5/config"
 20	"github.com/go-git/go-git/v5/plumbing"
 21	"github.com/go-git/go-git/v5/plumbing/filemode"
 22	"github.com/go-git/go-git/v5/plumbing/object"
 23	"golang.org/x/sync/errgroup"
 24	"golang.org/x/sys/execabs"
 25
 26	"github.com/git-bug/git-bug/util/lamport"
 27)
 28
 29const clockPath = "clocks"
 30const indexPath = "indexes"
 31
 32var _ ClockedRepo = &GoGitRepo{}
 33var _ TestedRepo = &GoGitRepo{}
 34
 35type GoGitRepo struct {
 36	// Unfortunately, some parts of go-git are not thread-safe so we have to cover them with a big fat mutex here.
 37	// See https://github.com/go-git/go-git/issues/48
 38	// See https://github.com/go-git/go-git/issues/208
 39	// See https://github.com/go-git/go-git/pull/186
 40	rMutex sync.Mutex
 41	r      *gogit.Repository
 42	path   string
 43
 44	clocksMutex sync.Mutex
 45	clocks      map[string]lamport.Clock
 46
 47	indexesMutex sync.Mutex
 48	indexes      map[string]Index
 49
 50	keyring      Keyring
 51	localStorage LocalStorage
 52}
 53
 54// OpenGoGitRepo opens an already existing repo at the given path and
 55// with the specified LocalStorage namespace.  Given a repository path
 56// of "~/myrepo" and a namespace of "git-bug", local storage for the
 57// GoGitRepo will be configured at "~/myrepo/.git/git-bug".
 58func OpenGoGitRepo(path, namespace string, clockLoaders []ClockLoader) (*GoGitRepo, error) {
 59	path, err := detectGitPath(path, 0)
 60	if err != nil {
 61		return nil, err
 62	}
 63
 64	r, err := gogit.PlainOpen(path)
 65	if err != nil {
 66		return nil, err
 67	}
 68
 69	k, err := defaultKeyring()
 70	if err != nil {
 71		return nil, err
 72	}
 73
 74	repo := &GoGitRepo{
 75		r:            r,
 76		path:         path,
 77		clocks:       make(map[string]lamport.Clock),
 78		indexes:      make(map[string]Index),
 79		keyring:      k,
 80		localStorage: billyLocalStorage{Filesystem: osfs.New(filepath.Join(path, namespace))},
 81	}
 82
 83	loaderToRun := make([]ClockLoader, 0, len(clockLoaders))
 84	for _, loader := range clockLoaders {
 85		loader := loader
 86		allExist := true
 87		for _, name := range loader.Clocks {
 88			if _, err := repo.getClock(name); err != nil {
 89				allExist = false
 90			}
 91		}
 92
 93		if !allExist {
 94			loaderToRun = append(loaderToRun, loader)
 95		}
 96	}
 97
 98	var errG errgroup.Group
 99	for _, loader := range loaderToRun {
100		loader := loader
101		errG.Go(func() error {
102			return loader.Witnesser(repo)
103		})
104	}
105	err = errG.Wait()
106	if err != nil {
107		return nil, err
108	}
109
110	return repo, nil
111}
112
113// InitGoGitRepo creates a new empty git repo at the given path and
114// with the specified LocalStorage namespace.  Given a repository path
115// of "~/myrepo" and a namespace of "git-bug", local storage for the
116// GoGitRepo will be configured at "~/myrepo/.git/git-bug".
117func InitGoGitRepo(path, namespace string) (*GoGitRepo, error) {
118	r, err := gogit.PlainInit(path, false)
119	if err != nil {
120		return nil, err
121	}
122
123	k, err := defaultKeyring()
124	if err != nil {
125		return nil, err
126	}
127
128	return &GoGitRepo{
129		r:            r,
130		path:         filepath.Join(path, ".git"),
131		clocks:       make(map[string]lamport.Clock),
132		indexes:      make(map[string]Index),
133		keyring:      k,
134		localStorage: billyLocalStorage{Filesystem: osfs.New(filepath.Join(path, ".git", namespace))},
135	}, nil
136}
137
138// InitBareGoGitRepo creates a new --bare empty git repo at the given
139// path and with the specified LocalStorage namespace.  Given a repository
140// path of "~/myrepo" and a namespace of "git-bug", local storage for the
141// GoGitRepo will be configured at "~/myrepo/.git/git-bug".
142func InitBareGoGitRepo(path, namespace string) (*GoGitRepo, error) {
143	r, err := gogit.PlainInit(path, true)
144	if err != nil {
145		return nil, err
146	}
147
148	k, err := defaultKeyring()
149	if err != nil {
150		return nil, err
151	}
152
153	return &GoGitRepo{
154		r:            r,
155		path:         path,
156		clocks:       make(map[string]lamport.Clock),
157		indexes:      make(map[string]Index),
158		keyring:      k,
159		localStorage: billyLocalStorage{Filesystem: osfs.New(filepath.Join(path, namespace))},
160	}, nil
161}
162
163func detectGitPath(path string, depth int) (string, error) {
164	if depth >= 10 {
165		return "", fmt.Errorf("gitdir loop detected")
166	}
167
168	// normalize the path
169	path, err := filepath.Abs(path)
170	if err != nil {
171		return "", err
172	}
173
174	for {
175		fi, err := os.Stat(filepath.Join(path, ".git"))
176		if err == nil {
177			if !fi.IsDir() {
178				// See if our .git item is a dotfile that holds a submodule reference
179				dotfile, err := os.Open(filepath.Join(path, fi.Name()))
180				if err != nil {
181					// Can't open error
182					return "", fmt.Errorf(".git exists but is not a directory or a readable file: %w", err)
183				}
184				// We aren't going to defer the dotfile.Close, because we might keep looping, so we have to be sure to
185				// clean up before returning an error
186				reader := bufio.NewReader(io.LimitReader(dotfile, 2048))
187				line, _, err := reader.ReadLine()
188				_ = dotfile.Close()
189				if err != nil {
190					return "", fmt.Errorf(".git exists but is not a directory and cannot be read: %w", err)
191				}
192				dotContent := string(line)
193				if strings.HasPrefix(dotContent, "gitdir:") {
194					// This is a submodule parent path link. Strip the prefix, clean the string of whitespace just to
195					// be safe, and return
196					dotContent = strings.TrimSpace(strings.TrimPrefix(dotContent, "gitdir: "))
197					p, err := detectGitPath(dotContent, depth+1)
198					if err != nil {
199						return "", fmt.Errorf(".git gitdir error: %w", err)
200					}
201					return p, nil
202				}
203				return "", fmt.Errorf(".git exist but is not a directory or module/workspace file")
204			}
205			return filepath.Join(path, ".git"), nil
206		}
207		if !os.IsNotExist(err) {
208			// unknown error
209			return "", err
210		}
211
212		// detect bare repo
213		ok, err := isGitDir(path)
214		if err != nil {
215			return "", err
216		}
217		if ok {
218			return path, nil
219		}
220
221		if parent := filepath.Dir(path); parent == path {
222			return "", fmt.Errorf(".git not found")
223		} else {
224			path = parent
225		}
226	}
227}
228
229func isGitDir(path string) (bool, error) {
230	markers := []string{"HEAD", "objects", "refs"}
231
232	for _, marker := range markers {
233		_, err := os.Stat(filepath.Join(path, marker))
234		if err == nil {
235			continue
236		}
237		if !os.IsNotExist(err) {
238			// unknown error
239			return false, err
240		} else {
241			return false, nil
242		}
243	}
244
245	return true, nil
246}
247
248func (repo *GoGitRepo) Close() error {
249	var firstErr error
250	for name, index := range repo.indexes {
251		err := index.Close()
252		if err != nil && firstErr == nil {
253			firstErr = err
254		}
255		delete(repo.indexes, name)
256	}
257	return firstErr
258}
259
260// LocalConfig give access to the repository scoped configuration
261func (repo *GoGitRepo) LocalConfig() Config {
262	return newGoGitLocalConfig(repo.r)
263}
264
265// GlobalConfig give access to the global scoped configuration
266func (repo *GoGitRepo) GlobalConfig() Config {
267	return newGoGitGlobalConfig()
268}
269
270// AnyConfig give access to a merged local/global configuration
271func (repo *GoGitRepo) AnyConfig() ConfigRead {
272	return mergeConfig(repo.LocalConfig(), repo.GlobalConfig())
273}
274
275// Keyring give access to a user-wide storage for secrets
276func (repo *GoGitRepo) Keyring() Keyring {
277	return repo.keyring
278}
279
280// GetUserName returns the name the user has used to configure git
281func (repo *GoGitRepo) GetUserName() (string, error) {
282	return repo.AnyConfig().ReadString("user.name")
283}
284
285// GetUserEmail returns the email address that the user has used to configure git.
286func (repo *GoGitRepo) GetUserEmail() (string, error) {
287	return repo.AnyConfig().ReadString("user.email")
288}
289
290// GetCoreEditor returns the name of the editor that the user has used to configure git.
291func (repo *GoGitRepo) GetCoreEditor() (string, error) {
292	// See https://git-scm.com/docs/git-var
293	// The order of preference is the $GIT_EDITOR environment variable, then core.editor configuration, then $VISUAL, then $EDITOR, and then the default chosen at compile time, which is usually vi.
294
295	if val, ok := os.LookupEnv("GIT_EDITOR"); ok {
296		return val, nil
297	}
298
299	val, err := repo.AnyConfig().ReadString("core.editor")
300	if err == nil && val != "" {
301		return val, nil
302	}
303	if err != nil && !errors.Is(err, ErrNoConfigEntry) {
304		return "", err
305	}
306
307	if val, ok := os.LookupEnv("VISUAL"); ok {
308		return val, nil
309	}
310
311	if val, ok := os.LookupEnv("EDITOR"); ok {
312		return val, nil
313	}
314
315	priorities := []string{
316		"editor",
317		"nano",
318		"vim",
319		"vi",
320		"emacs",
321	}
322
323	for _, cmd := range priorities {
324		if _, err = execabs.LookPath(cmd); err == nil {
325			return cmd, nil
326		}
327
328	}
329
330	return "ed", nil
331}
332
333// GetRemotes returns the configured remotes repositories.
334func (repo *GoGitRepo) GetRemotes() (map[string]string, error) {
335	cfg, err := repo.r.Config()
336	if err != nil {
337		return nil, err
338	}
339
340	result := make(map[string]string, len(cfg.Remotes))
341	for name, remote := range cfg.Remotes {
342		if len(remote.URLs) > 0 {
343			result[name] = remote.URLs[0]
344		}
345	}
346
347	return result, nil
348}
349
350// LocalStorage returns a billy.Filesystem giving access to
351// $RepoPath/.git/$Namespace.
352func (repo *GoGitRepo) LocalStorage() LocalStorage {
353	return repo.localStorage
354}
355
356func (repo *GoGitRepo) GetIndex(name string) (Index, error) {
357	repo.indexesMutex.Lock()
358	defer repo.indexesMutex.Unlock()
359
360	if index, ok := repo.indexes[name]; ok {
361		return index, nil
362	}
363
364	path := filepath.Join(repo.localStorage.Root(), indexPath, name)
365
366	index, err := openBleveIndex(path)
367	if err == nil {
368		repo.indexes[name] = index
369	}
370	return index, err
371}
372
373// FetchRefs fetch git refs matching a directory prefix to a remote
374// Ex: prefix="foo" will fetch any remote refs matching "refs/foo/*" locally.
375// The equivalent git refspec would be "refs/foo/*:refs/remotes/<remote>/foo/*"
376func (repo *GoGitRepo) FetchRefs(remote string, prefixes ...string) (string, error) {
377	refSpecs := make([]config.RefSpec, len(prefixes))
378
379	for i, prefix := range prefixes {
380		refSpecs[i] = config.RefSpec(fmt.Sprintf("refs/%s/*:refs/remotes/%s/%s/*", prefix, remote, prefix))
381	}
382
383	buf := bytes.NewBuffer(nil)
384
385	err := repo.r.Fetch(&gogit.FetchOptions{
386		RemoteName: remote,
387		RefSpecs:   refSpecs,
388		Progress:   buf,
389	})
390	if err == gogit.NoErrAlreadyUpToDate {
391		return "already up-to-date", nil
392	}
393	if err != nil {
394		return "", err
395	}
396
397	return buf.String(), nil
398}
399
400// PushRefs push git refs matching a directory prefix to a remote
401// Ex: prefix="foo" will push any local refs matching "refs/foo/*" to the remote.
402// The equivalent git refspec would be "refs/foo/*:refs/foo/*"
403//
404// Additionally, PushRefs will update the local references in refs/remotes/<remote>/foo to match
405// the remote state.
406func (repo *GoGitRepo) PushRefs(remote string, prefixes ...string) (string, error) {
407	remo, err := repo.r.Remote(remote)
408	if err != nil {
409		return "", err
410	}
411
412	refSpecs := make([]config.RefSpec, len(prefixes))
413
414	for i, prefix := range prefixes {
415		refspec := fmt.Sprintf("refs/%s/*:refs/%s/*", prefix, prefix)
416
417		// to make sure that the push also create the corresponding refs/remotes/<remote>/... references,
418		// we need to have a default fetch refspec configured on the remote, to make our refs "track" the remote ones.
419		// This does not change the config on disk, only on memory.
420		hasCustomFetch := false
421		fetchRefspec := fmt.Sprintf("refs/%s/*:refs/remotes/%s/%s/*", prefix, remote, prefix)
422		for _, r := range remo.Config().Fetch {
423			if string(r) == fetchRefspec {
424				hasCustomFetch = true
425				break
426			}
427		}
428
429		if !hasCustomFetch {
430			remo.Config().Fetch = append(remo.Config().Fetch, config.RefSpec(fetchRefspec))
431		}
432
433		refSpecs[i] = config.RefSpec(refspec)
434	}
435
436	buf := bytes.NewBuffer(nil)
437
438	err = remo.Push(&gogit.PushOptions{
439		RemoteName: remote,
440		RefSpecs:   refSpecs,
441		Progress:   buf,
442	})
443	if err == gogit.NoErrAlreadyUpToDate {
444		return "already up-to-date", nil
445	}
446	if err != nil {
447		return "", err
448	}
449
450	return buf.String(), nil
451}
452
453// StoreData will store arbitrary data and return the corresponding hash
454func (repo *GoGitRepo) StoreData(data []byte) (Hash, error) {
455	obj := repo.r.Storer.NewEncodedObject()
456	obj.SetType(plumbing.BlobObject)
457
458	w, err := obj.Writer()
459	if err != nil {
460		return "", err
461	}
462
463	_, err = w.Write(data)
464	if err != nil {
465		return "", err
466	}
467
468	h, err := repo.r.Storer.SetEncodedObject(obj)
469	if err != nil {
470		return "", err
471	}
472
473	return Hash(h.String()), nil
474}
475
476// ReadData will attempt to read arbitrary data from the given hash
477func (repo *GoGitRepo) ReadData(hash Hash) ([]byte, error) {
478	repo.rMutex.Lock()
479	defer repo.rMutex.Unlock()
480
481	obj, err := repo.r.BlobObject(plumbing.NewHash(hash.String()))
482	if err == plumbing.ErrObjectNotFound {
483		return nil, ErrNotFound
484	}
485	if err != nil {
486		return nil, err
487	}
488
489	r, err := obj.Reader()
490	if err != nil {
491		return nil, err
492	}
493
494	// TODO: return a io.Reader instead
495	return io.ReadAll(r)
496}
497
498// StoreTree will store a mapping key-->Hash as a Git tree
499func (repo *GoGitRepo) StoreTree(mapping []TreeEntry) (Hash, error) {
500	var tree object.Tree
501
502	// TODO: can be removed once https://github.com/go-git/go-git/issues/193 is resolved
503	sorted := make([]TreeEntry, len(mapping))
504	copy(sorted, mapping)
505	sort.Slice(sorted, func(i, j int) bool {
506		nameI := sorted[i].Name
507		if sorted[i].ObjectType == Tree {
508			nameI += "/"
509		}
510		nameJ := sorted[j].Name
511		if sorted[j].ObjectType == Tree {
512			nameJ += "/"
513		}
514		return nameI < nameJ
515	})
516
517	for _, entry := range sorted {
518		mode := filemode.Regular
519		if entry.ObjectType == Tree {
520			mode = filemode.Dir
521		}
522
523		tree.Entries = append(tree.Entries, object.TreeEntry{
524			Name: entry.Name,
525			Mode: mode,
526			Hash: plumbing.NewHash(entry.Hash.String()),
527		})
528	}
529
530	obj := repo.r.Storer.NewEncodedObject()
531	obj.SetType(plumbing.TreeObject)
532	err := tree.Encode(obj)
533	if err != nil {
534		return "", err
535	}
536
537	hash, err := repo.r.Storer.SetEncodedObject(obj)
538	if err != nil {
539		return "", err
540	}
541
542	return Hash(hash.String()), nil
543}
544
545// ReadTree will return the list of entries in a Git tree
546func (repo *GoGitRepo) ReadTree(hash Hash) ([]TreeEntry, error) {
547	repo.rMutex.Lock()
548	defer repo.rMutex.Unlock()
549
550	h := plumbing.NewHash(hash.String())
551
552	// the given hash could be a tree or a commit
553	obj, err := repo.r.Storer.EncodedObject(plumbing.AnyObject, h)
554	if err == plumbing.ErrObjectNotFound {
555		return nil, ErrNotFound
556	}
557	if err != nil {
558		return nil, err
559	}
560
561	var tree *object.Tree
562	switch obj.Type() {
563	case plumbing.TreeObject:
564		tree, err = object.DecodeTree(repo.r.Storer, obj)
565	case plumbing.CommitObject:
566		var commit *object.Commit
567		commit, err = object.DecodeCommit(repo.r.Storer, obj)
568		if err != nil {
569			return nil, err
570		}
571		tree, err = commit.Tree()
572	default:
573		return nil, fmt.Errorf("given hash is not a tree")
574	}
575	if err != nil {
576		return nil, err
577	}
578
579	treeEntries := make([]TreeEntry, len(tree.Entries))
580	for i, entry := range tree.Entries {
581		objType := Blob
582		if entry.Mode == filemode.Dir {
583			objType = Tree
584		}
585
586		treeEntries[i] = TreeEntry{
587			ObjectType: objType,
588			Hash:       Hash(entry.Hash.String()),
589			Name:       entry.Name,
590		}
591	}
592
593	return treeEntries, nil
594}
595
596// StoreCommit will store a Git commit with the given Git tree
597func (repo *GoGitRepo) StoreCommit(treeHash Hash, parents ...Hash) (Hash, error) {
598	return repo.StoreSignedCommit(treeHash, nil, parents...)
599}
600
601// StoreSignedCommit will store a Git commit with the given Git tree. If signKey is not nil, the commit
602// will be signed accordingly.
603func (repo *GoGitRepo) StoreSignedCommit(treeHash Hash, signKey *openpgp.Entity, parents ...Hash) (Hash, error) {
604	cfg, err := repo.r.Config()
605	if err != nil {
606		return "", err
607	}
608
609	commit := object.Commit{
610		Author: object.Signature{
611			Name:  cfg.Author.Name,
612			Email: cfg.Author.Email,
613			When:  time.Now(),
614		},
615		Committer: object.Signature{
616			Name:  cfg.Committer.Name,
617			Email: cfg.Committer.Email,
618			When:  time.Now(),
619		},
620		Message:  "",
621		TreeHash: plumbing.NewHash(treeHash.String()),
622	}
623
624	for _, parent := range parents {
625		commit.ParentHashes = append(commit.ParentHashes, plumbing.NewHash(parent.String()))
626	}
627
628	// Compute the signature if needed
629	if signKey != nil {
630		// first get the serialized commit
631		encoded := &plumbing.MemoryObject{}
632		if err := commit.Encode(encoded); err != nil {
633			return "", err
634		}
635		r, err := encoded.Reader()
636		if err != nil {
637			return "", err
638		}
639
640		// sign the data
641		var sig bytes.Buffer
642		if err := openpgp.ArmoredDetachSign(&sig, signKey, r, nil); err != nil {
643			return "", err
644		}
645		commit.PGPSignature = sig.String()
646	}
647
648	obj := repo.r.Storer.NewEncodedObject()
649	obj.SetType(plumbing.CommitObject)
650	err = commit.Encode(obj)
651	if err != nil {
652		return "", err
653	}
654
655	hash, err := repo.r.Storer.SetEncodedObject(obj)
656	if err != nil {
657		return "", err
658	}
659
660	return Hash(hash.String()), nil
661}
662
663func (repo *GoGitRepo) ResolveRef(ref string) (Hash, error) {
664	r, err := repo.r.Reference(plumbing.ReferenceName(ref), false)
665	if err == plumbing.ErrReferenceNotFound {
666		return "", ErrNotFound
667	}
668	if err != nil {
669		return "", err
670	}
671	return Hash(r.Hash().String()), nil
672}
673
674// UpdateRef will create or update a Git reference
675func (repo *GoGitRepo) UpdateRef(ref string, hash Hash) error {
676	return repo.r.Storer.SetReference(plumbing.NewHashReference(plumbing.ReferenceName(ref), plumbing.NewHash(hash.String())))
677}
678
679// RemoveRef will remove a Git reference
680func (repo *GoGitRepo) RemoveRef(ref string) error {
681	return repo.r.Storer.RemoveReference(plumbing.ReferenceName(ref))
682}
683
684// ListRefs will return a list of Git ref matching the given refspec
685func (repo *GoGitRepo) ListRefs(refPrefix string) ([]string, error) {
686	refIter, err := repo.r.References()
687	if err != nil {
688		return nil, err
689	}
690
691	refs := make([]string, 0)
692
693	err = refIter.ForEach(func(ref *plumbing.Reference) error {
694		if strings.HasPrefix(ref.Name().String(), refPrefix) {
695			refs = append(refs, ref.Name().String())
696		}
697		return nil
698	})
699	if err != nil {
700		return nil, err
701	}
702
703	return refs, nil
704}
705
706// RefExist will check if a reference exist in Git
707func (repo *GoGitRepo) RefExist(ref string) (bool, error) {
708	_, err := repo.r.Reference(plumbing.ReferenceName(ref), false)
709	if err == nil {
710		return true, nil
711	} else if err == plumbing.ErrReferenceNotFound {
712		return false, nil
713	}
714	return false, err
715}
716
717// CopyRef will create a new reference with the same value as another one
718func (repo *GoGitRepo) CopyRef(source string, dest string) error {
719	r, err := repo.r.Reference(plumbing.ReferenceName(source), false)
720	if err == plumbing.ErrReferenceNotFound {
721		return ErrNotFound
722	}
723	if err != nil {
724		return err
725	}
726	return repo.r.Storer.SetReference(plumbing.NewHashReference(plumbing.ReferenceName(dest), r.Hash()))
727}
728
729// ListCommits will return the list of tree hashes of a ref, in chronological order
730func (repo *GoGitRepo) ListCommits(ref string) ([]Hash, error) {
731	return nonNativeListCommits(repo, ref)
732}
733
734func (repo *GoGitRepo) ReadCommit(hash Hash) (Commit, error) {
735	repo.rMutex.Lock()
736	defer repo.rMutex.Unlock()
737
738	commit, err := repo.r.CommitObject(plumbing.NewHash(hash.String()))
739	if err == plumbing.ErrObjectNotFound {
740		return Commit{}, ErrNotFound
741	}
742	if err != nil {
743		return Commit{}, err
744	}
745
746	parents := make([]Hash, len(commit.ParentHashes))
747	for i, parentHash := range commit.ParentHashes {
748		parents[i] = Hash(parentHash.String())
749	}
750
751	result := Commit{
752		Hash:     hash,
753		Parents:  parents,
754		TreeHash: Hash(commit.TreeHash.String()),
755	}
756
757	if commit.PGPSignature != "" {
758		// I can't find a way to just remove the signature when reading the encoded commit so we need to
759		// re-encode the commit without signature.
760
761		encoded := &plumbing.MemoryObject{}
762		err := commit.EncodeWithoutSignature(encoded)
763		if err != nil {
764			return Commit{}, err
765		}
766
767		result.SignedData, err = encoded.Reader()
768		if err != nil {
769			return Commit{}, err
770		}
771
772		result.Signature, err = deArmorSignature(strings.NewReader(commit.PGPSignature))
773		if err != nil {
774			return Commit{}, err
775		}
776	}
777
778	return result, nil
779}
780
781func (repo *GoGitRepo) AllClocks() (map[string]lamport.Clock, error) {
782	repo.clocksMutex.Lock()
783	defer repo.clocksMutex.Unlock()
784
785	result := make(map[string]lamport.Clock)
786
787	files, err := os.ReadDir(filepath.Join(repo.localStorage.Root(), clockPath))
788	if os.IsNotExist(err) {
789		return nil, nil
790	}
791	if err != nil {
792		return nil, err
793	}
794
795	for _, file := range files {
796		name := file.Name()
797		if c, ok := repo.clocks[name]; ok {
798			result[name] = c
799		} else {
800			c, err := lamport.LoadPersistedClock(repo.LocalStorage(), filepath.Join(clockPath, name))
801			if err != nil {
802				return nil, err
803			}
804			repo.clocks[name] = c
805			result[name] = c
806		}
807	}
808
809	return result, nil
810}
811
812// GetOrCreateClock return a Lamport clock stored in the Repo.
813// If the clock doesn't exist, it's created.
814func (repo *GoGitRepo) GetOrCreateClock(name string) (lamport.Clock, error) {
815	repo.clocksMutex.Lock()
816	defer repo.clocksMutex.Unlock()
817
818	c, err := repo.getClock(name)
819	if err == nil {
820		return c, nil
821	}
822	if err != ErrClockNotExist {
823		return nil, err
824	}
825
826	c, err = lamport.NewPersistedClock(repo.LocalStorage(), filepath.Join(clockPath, name))
827	if err != nil {
828		return nil, err
829	}
830
831	repo.clocks[name] = c
832	return c, nil
833}
834
835func (repo *GoGitRepo) getClock(name string) (lamport.Clock, error) {
836	if c, ok := repo.clocks[name]; ok {
837		return c, nil
838	}
839
840	c, err := lamport.LoadPersistedClock(repo.LocalStorage(), filepath.Join(clockPath, name))
841	if err == nil {
842		repo.clocks[name] = c
843		return c, nil
844	}
845	if err == lamport.ErrClockNotExist {
846		return nil, ErrClockNotExist
847	}
848	return nil, err
849}
850
851// Increment is equivalent to c = GetOrCreateClock(name) + c.Increment()
852func (repo *GoGitRepo) Increment(name string) (lamport.Time, error) {
853	c, err := repo.GetOrCreateClock(name)
854	if err != nil {
855		return lamport.Time(0), err
856	}
857	return c.Increment()
858}
859
860// Witness is equivalent to c = GetOrCreateClock(name) + c.Witness(time)
861func (repo *GoGitRepo) Witness(name string, time lamport.Time) error {
862	c, err := repo.GetOrCreateClock(name)
863	if err != nil {
864		return err
865	}
866	return c.Witness(time)
867}
868
869// AddRemote add a new remote to the repository
870// Not in the interface because it's only used for testing
871func (repo *GoGitRepo) AddRemote(name string, url string) error {
872	_, err := repo.r.CreateRemote(&config.RemoteConfig{
873		Name: name,
874		URLs: []string{url},
875	})
876
877	return err
878}
879
880// GetLocalRemote return the URL to use to add this repo as a local remote
881func (repo *GoGitRepo) GetLocalRemote() string {
882	return repo.path
883}
884
885// EraseFromDisk delete this repository entirely from the disk
886func (repo *GoGitRepo) EraseFromDisk() error {
887	err := repo.Close()
888	if err != nil {
889		return err
890	}
891
892	path := filepath.Clean(strings.TrimSuffix(repo.path, string(filepath.Separator)+".git"))
893
894	// fmt.Println("Cleaning repo:", path)
895	return os.RemoveAll(path)
896}