diff options
| author | 2026-03-06 10:59:53 +0800 | |
|---|---|---|
| committer | 2026-03-06 10:59:53 +0800 | |
| commit | 95f8f3d45fe077042df4fd4afa73d4e419bc9974 (patch) | |
| tree | 1e650b788eb4fbe5fc61ad0df700de58ebba40c5 /reachability/walk.go | |
| parent | format/commitgraph: Split layer files (diff) | |
| signature | No signature | |
reachability: Split walk files
Diffstat (limited to 'reachability/walk.go')
| -rw-r--r-- | reachability/walk.go | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/reachability/walk.go b/reachability/walk.go index 4611e46e..13400e89 100644 --- a/reachability/walk.go +++ b/reachability/walk.go @@ -1,14 +1,7 @@ package reachability import ( - "errors" - "fmt" - "iter" - - "codeberg.org/lindenii/furgit/format/commitgraph" - "codeberg.org/lindenii/furgit/object" "codeberg.org/lindenii/furgit/objectid" - "codeberg.org/lindenii/furgit/objecttype" ) // Walk is one single-use iterator-style traversal. @@ -22,295 +15,3 @@ type Walk struct { seqUsed bool err error } - -// Seq returns the traversal sequence. It is single-use. -func (walk *Walk) Seq() iter.Seq[objectid.ObjectID] { - if walk.seqUsed { - return func(yield func(objectid.ObjectID) bool) { - _ = yield - - if walk.err == nil { - walk.err = errors.New("reachability: walk sequence already consumed") - } - } - } - - walk.seqUsed = true - - return func(yield func(objectid.ObjectID) bool) { - if walk.err != nil { - return - } - - stack := walk.initialStack() - - var err error - - visited := make(map[objectid.ObjectID]struct{}, len(stack)) - for len(stack) > 0 { - item := stack[len(stack)-1] - stack = stack[:len(stack)-1] - - if containsOID(walk.haves, item.id) { - continue - } - - if _, ok := visited[item.id]; ok { - continue - } - - visited[item.id] = struct{}{} - - var next []walkItem - - next, err = walk.expand(item) - if err != nil { - walk.err = err - - return - } - - if !yield(item.id) { - return - } - - stack = append(stack, next...) - } - } -} - -// Err returns the terminal error, if any, once Seq has been consumed. -func (walk *Walk) Err() error { - return walk.err -} - -type walkItem struct { - id objectid.ObjectID - want objecttype.Type -} - -func (walk *Walk) initialStack() []walkItem { - if len(walk.wants) == 0 { - return nil - } - - stack := make([]walkItem, 0, len(walk.wants)) - for want := range walk.wants { - stack = append(stack, walkItem{id: want, want: objecttype.TypeInvalid}) - } - - return stack -} - -func (walk *Walk) expand(item walkItem) ([]walkItem, error) { - if walk.domain == DomainCommits { - return walk.expandCommits(item) - } - - return walk.expandObjects(item) -} - -func (walk *Walk) expandCommits(item walkItem) ([]walkItem, error) { - if walk.reachability.graph != nil { //nolint:nestif - next, graphUsed, err := walk.expandCommitsFromGraph(item.id) - if err != nil { - return nil, err - } - - if graphUsed && walk.strict { - err = walk.validateCommitObject(item.id) - if err != nil { - return nil, err - } - } - - if graphUsed { - return next, nil - } - } - - ty, err := walk.readHeaderType(item.id) - if err != nil { - return nil, err - } - - switch ty { - case objecttype.TypeCommit: - content, err := walk.readBytesContent(item.id) - if err != nil { - return nil, err - } - - commit, err := object.ParseCommit(content, item.id.Algorithm()) - if err != nil { - return nil, err - } - - next := make([]walkItem, 0, len(commit.Parents)) - for _, parent := range commit.Parents { - next = append(next, walkItem{id: parent, want: objecttype.TypeInvalid}) - } - - return next, nil - case objecttype.TypeTag: - content, err := walk.readBytesContent(item.id) - if err != nil { - return nil, err - } - - tag, err := object.ParseTag(content, item.id.Algorithm()) - if err != nil { - return nil, err - } - - return []walkItem{{id: tag.Target, want: objecttype.TypeInvalid}}, nil - case objecttype.TypeTree, objecttype.TypeBlob, objecttype.TypeInvalid, - objecttype.TypeFuture, objecttype.TypeOfsDelta, objecttype.TypeRefDelta: - return nil, &ErrObjectType{OID: item.id, Got: ty, Want: objecttype.TypeCommit} - } - - return nil, fmt.Errorf("reachability: unreachable object type %d", ty) -} - -func (walk *Walk) validateCommitObject(id objectid.ObjectID) error { - ty, err := walk.readHeaderType(id) - if err != nil { - return err - } - - if ty != objecttype.TypeCommit { - return &ErrObjectType{OID: id, Got: ty, Want: objecttype.TypeCommit} - } - - content, err := walk.readBytesContent(id) - if err != nil { - return err - } - - _, err = object.ParseCommit(content, id.Algorithm()) - - return err -} - -func (walk *Walk) expandCommitsFromGraph(id objectid.ObjectID) ([]walkItem, bool, error) { - pos, err := walk.reachability.graph.Lookup(id) - if err != nil { - var notFound *commitgraph.ErrNotFound - if errors.As(err, ¬Found) { - return nil, false, nil - } - - return nil, true, err - } - - commit, err := walk.reachability.graph.CommitAt(pos) - if err != nil { - return nil, true, err - } - - next := make([]walkItem, 0, 2+len(commit.ExtraParents)) - - if commit.Parent1.Valid { - parentOID, err := walk.reachability.graph.OIDAt(commit.Parent1.Pos) - if err != nil { - return nil, true, err - } - - next = append(next, walkItem{id: parentOID, want: objecttype.TypeInvalid}) - } - - if commit.Parent2.Valid { - parentOID, err := walk.reachability.graph.OIDAt(commit.Parent2.Pos) - if err != nil { - return nil, true, err - } - - next = append(next, walkItem{id: parentOID, want: objecttype.TypeInvalid}) - } - - for _, parentPos := range commit.ExtraParents { - parentOID, err := walk.reachability.graph.OIDAt(parentPos) - if err != nil { - return nil, true, err - } - - next = append(next, walkItem{id: parentOID, want: objecttype.TypeInvalid}) - } - - return next, true, nil -} - -func (walk *Walk) expandObjects(item walkItem) ([]walkItem, error) { - ty, err := walk.readHeaderType(item.id) - if err != nil { - return nil, err - } - - if item.want != objecttype.TypeInvalid && ty != item.want { - return nil, &ErrObjectType{OID: item.id, Got: ty, Want: item.want} - } - - switch ty { - case objecttype.TypeBlob: - return nil, nil - case objecttype.TypeCommit: - content, err := walk.readBytesContent(item.id) - if err != nil { - return nil, err - } - - commit, err := object.ParseCommit(content, item.id.Algorithm()) - if err != nil { - return nil, err - } - - next := make([]walkItem, 0, len(commit.Parents)+1) - - next = append(next, walkItem{id: commit.Tree, want: objecttype.TypeTree}) - for _, parent := range commit.Parents { - next = append(next, walkItem{id: parent, want: objecttype.TypeCommit}) - } - - return next, nil - case objecttype.TypeTree: - content, err := walk.readBytesContent(item.id) - if err != nil { - return nil, err - } - - tree, err := object.ParseTree(content, item.id.Algorithm()) - if err != nil { - return nil, err - } - - next := make([]walkItem, 0, len(tree.Entries)) - for _, entry := range tree.Entries { - switch entry.Mode { - case object.FileModeGitlink: - continue - case object.FileModeDir: - next = append(next, walkItem{id: entry.ID, want: objecttype.TypeTree}) - case object.FileModeRegular, object.FileModeExecutable, object.FileModeSymlink: - next = append(next, walkItem{id: entry.ID, want: objecttype.TypeBlob}) - } - } - - return next, nil - case objecttype.TypeTag: - content, err := walk.readBytesContent(item.id) - if err != nil { - return nil, err - } - - tag, err := object.ParseTag(content, item.id.Algorithm()) - if err != nil { - return nil, err - } - - return []walkItem{{id: tag.Target, want: tag.TargetType}}, nil - case objecttype.TypeInvalid, objecttype.TypeFuture, objecttype.TypeOfsDelta, objecttype.TypeRefDelta: - return nil, &ErrObjectType{OID: item.id, Got: ty, Want: item.want} - } - - return nil, fmt.Errorf("reachability: unreachable object type %d", ty) -} |
