--- /dev/null
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cache
+
+import (
+ "context"
+ "fmt"
+ "os"
+ "path/filepath"
+ "strconv"
+ "strings"
+ "sync"
+ "sync/atomic"
+
+ "golang.org/x/tools/internal/event"
+ "golang.org/x/tools/internal/gocommand"
+ "golang.org/x/tools/internal/imports"
+ "golang.org/x/tools/internal/lsp/source"
+ "golang.org/x/tools/internal/span"
+ "golang.org/x/tools/internal/xcontext"
+ errors "golang.org/x/xerrors"
+)
+
+type Session struct {
+ cache *Cache
+ id string
+
+ optionsMu sync.Mutex
+ options *source.Options
+
+ viewMu sync.Mutex
+ views []*View
+ viewMap map[span.URI]*View
+
+ overlayMu sync.Mutex
+ overlays map[span.URI]*overlay
+
+ // gocmdRunner guards go command calls from concurrency errors.
+ gocmdRunner *gocommand.Runner
+}
+
+type overlay struct {
+ session *Session
+ uri span.URI
+ text []byte
+ hash string
+ version float64
+ kind source.FileKind
+
+ // saved is true if a file matches the state on disk,
+ // and therefore does not need to be part of the overlay sent to go/packages.
+ saved bool
+}
+
+func (o *overlay) Read() ([]byte, error) {
+ return o.text, nil
+}
+
+func (o *overlay) FileIdentity() source.FileIdentity {
+ return source.FileIdentity{
+ URI: o.uri,
+ Hash: o.hash,
+ Kind: o.kind,
+ }
+}
+
+func (o *overlay) VersionedFileIdentity() source.VersionedFileIdentity {
+ return source.VersionedFileIdentity{
+ URI: o.uri,
+ SessionID: o.session.id,
+ Version: o.version,
+ }
+}
+
+func (o *overlay) Kind() source.FileKind {
+ return o.kind
+}
+
+func (o *overlay) URI() span.URI {
+ return o.uri
+}
+
+func (o *overlay) Version() float64 {
+ return o.version
+}
+
+func (o *overlay) Session() string {
+ return o.session.id
+}
+
+func (o *overlay) Saved() bool {
+ return o.saved
+}
+
+// closedFile implements LSPFile for a file that the editor hasn't told us about.
+type closedFile struct {
+ source.FileHandle
+}
+
+func (c *closedFile) VersionedFileIdentity() source.VersionedFileIdentity {
+ return source.VersionedFileIdentity{
+ URI: c.FileHandle.URI(),
+ SessionID: "",
+ Version: 0,
+ }
+}
+
+func (c *closedFile) Session() string {
+ return ""
+}
+
+func (c *closedFile) Version() float64 {
+ return 0
+}
+
+func (s *Session) ID() string { return s.id }
+func (s *Session) String() string { return s.id }
+
+func (s *Session) Options() *source.Options {
+ s.optionsMu.Lock()
+ defer s.optionsMu.Unlock()
+ return s.options
+}
+
+func (s *Session) SetOptions(options *source.Options) {
+ s.optionsMu.Lock()
+ defer s.optionsMu.Unlock()
+ s.options = options
+}
+
+func (s *Session) Shutdown(ctx context.Context) {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ for _, view := range s.views {
+ view.shutdown(ctx)
+ }
+ s.views = nil
+ s.viewMap = nil
+ event.Log(ctx, "Shutdown session", KeyShutdownSession.Of(s))
+}
+
+func (s *Session) Cache() interface{} {
+ return s.cache
+}
+
+func (s *Session) NewView(ctx context.Context, name string, folder span.URI, options *source.Options) (source.View, source.Snapshot, func(), error) {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ view, snapshot, release, err := s.createView(ctx, name, folder, options, 0)
+ if err != nil {
+ return nil, nil, func() {}, err
+ }
+ s.views = append(s.views, view)
+ // we always need to drop the view map
+ s.viewMap = make(map[span.URI]*View)
+ return view, snapshot, release, nil
+}
+
+func (s *Session) createView(ctx context.Context, name string, folder span.URI, options *source.Options, snapshotID uint64) (*View, *snapshot, func(), error) {
+ index := atomic.AddInt64(&viewIndex, 1)
+
+ if s.cache.options != nil {
+ s.cache.options(options)
+ }
+
+ // Set the module-specific information.
+ ws, err := s.getWorkspaceInformation(ctx, folder, options)
+ if err != nil {
+ return nil, nil, func() {}, err
+ }
+
+ // If workspace module mode is enabled, find all of the modules in the
+ // workspace. By default, we just find the root module.
+ var modules map[span.URI]*moduleRoot
+ modules, err = findWorkspaceModules(ctx, ws.rootURI, options)
+ if err != nil {
+ return nil, nil, func() {}, err
+ }
+
+ // We want a true background context and not a detached context here
+ // the spans need to be unrelated and no tag values should pollute it.
+ baseCtx := event.Detach(xcontext.Detach(ctx))
+ backgroundCtx, cancel := context.WithCancel(baseCtx)
+
+ v := &View{
+ session: s,
+ initialized: make(chan struct{}),
+ initializationSema: make(chan struct{}, 1),
+ initializeOnce: &sync.Once{},
+ id: strconv.FormatInt(index, 10),
+ options: options,
+ baseCtx: baseCtx,
+ backgroundCtx: backgroundCtx,
+ cancel: cancel,
+ name: name,
+ folder: folder,
+ filesByURI: make(map[span.URI]*fileBase),
+ filesByBase: make(map[string][]*fileBase),
+ workspaceInformation: *ws,
+ }
+ v.importsState = &importsState{
+ ctx: backgroundCtx,
+ processEnv: &imports.ProcessEnv{
+ GocmdRunner: s.gocmdRunner,
+ WorkingDir: folder.Filename(),
+ Env: ws.goEnv,
+ },
+ }
+ v.snapshot = &snapshot{
+ id: snapshotID,
+ view: v,
+ generation: s.cache.store.Generation(generationName(v, 0)),
+ packages: make(map[packageKey]*packageHandle),
+ ids: make(map[span.URI][]packageID),
+ metadata: make(map[packageID]*metadata),
+ files: make(map[span.URI]source.VersionedFileHandle),
+ goFiles: make(map[parseKey]*parseGoHandle),
+ importedBy: make(map[packageID][]packageID),
+ actions: make(map[actionKey]*actionHandle),
+ workspacePackages: make(map[packageID]packagePath),
+ unloadableFiles: make(map[span.URI]struct{}),
+ parseModHandles: make(map[span.URI]*parseModHandle),
+ modTidyHandles: make(map[span.URI]*modTidyHandle),
+ modUpgradeHandles: make(map[span.URI]*modUpgradeHandle),
+ modWhyHandles: make(map[span.URI]*modWhyHandle),
+ modules: modules,
+ }
+
+ v.snapshot.workspaceDirectories = v.snapshot.findWorkspaceDirectories(ctx)
+
+ // Initialize the view without blocking.
+ initCtx, initCancel := context.WithCancel(xcontext.Detach(ctx))
+ v.initCancelFirstAttempt = initCancel
+ snapshot := v.snapshot
+ release := snapshot.generation.Acquire(initCtx)
+ go func() {
+ snapshot.initialize(initCtx, true)
+ release()
+ }()
+ return v, snapshot, snapshot.generation.Acquire(ctx), nil
+}
+
+// findWorkspaceModules walks the view's root folder, looking for go.mod files.
+// Any that are found are added to the view's set of modules, which are then
+// used to construct the workspace module.
+//
+// It assumes that the caller has not yet created the view, and therefore does
+// not lock any of the internal data structures before accessing them.
+//
+// TODO(rstambler): Check overlays for go.mod files.
+func findWorkspaceModules(ctx context.Context, root span.URI, options *source.Options) (map[span.URI]*moduleRoot, error) {
+ // Walk the view's folder to find all modules in the view.
+ modules := make(map[span.URI]*moduleRoot)
+ if !options.ExperimentalWorkspaceModule {
+ path := filepath.Join(root.Filename(), "go.mod")
+ if info, _ := os.Stat(path); info != nil {
+ if m := getViewModule(ctx, root, span.URIFromPath(path), options); m != nil {
+ modules[m.rootURI] = m
+ }
+ }
+ return modules, nil
+ }
+ return modules, filepath.Walk(root.Filename(), func(path string, info os.FileInfo, err error) error {
+ if err != nil {
+ // Probably a permission error. Keep looking.
+ return filepath.SkipDir
+ }
+ // For any path that is not the workspace folder, check if the path
+ // would be ignored by the go command. Vendor directories also do not
+ // contain workspace modules.
+ if info.IsDir() && path != root.Filename() {
+ suffix := strings.TrimPrefix(path, root.Filename())
+ switch {
+ case checkIgnored(suffix),
+ strings.Contains(filepath.ToSlash(suffix), "/vendor/"):
+ return filepath.SkipDir
+ }
+ }
+ // We're only interested in go.mod files.
+ if filepath.Base(path) == "go.mod" {
+ if m := getViewModule(ctx, root, span.URIFromPath(path), options); m != nil {
+ modules[m.rootURI] = m
+ }
+ }
+ return nil
+ })
+}
+
+// View returns the view by name.
+func (s *Session) View(name string) source.View {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ for _, view := range s.views {
+ if view.Name() == name {
+ return view
+ }
+ }
+ return nil
+}
+
+// ViewOf returns a view corresponding to the given URI.
+// If the file is not already associated with a view, pick one using some heuristics.
+func (s *Session) ViewOf(uri span.URI) (source.View, error) {
+ return s.viewOf(uri)
+}
+
+func (s *Session) viewOf(uri span.URI) (*View, error) {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+
+ // Check if we already know this file.
+ if v, found := s.viewMap[uri]; found {
+ return v, nil
+ }
+ // Pick the best view for this file and memoize the result.
+ v, err := s.bestView(uri)
+ if err != nil {
+ return nil, err
+ }
+ s.viewMap[uri] = v
+ return v, nil
+}
+
+func (s *Session) viewsOf(uri span.URI) []*View {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+
+ var views []*View
+ for _, view := range s.views {
+ if strings.HasPrefix(string(uri), string(view.Folder())) {
+ views = append(views, view)
+ }
+ }
+ return views
+}
+
+func (s *Session) Views() []source.View {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ result := make([]source.View, len(s.views))
+ for i, v := range s.views {
+ result[i] = v
+ }
+ return result
+}
+
+// bestView finds the best view to associate a given URI with.
+// viewMu must be held when calling this method.
+func (s *Session) bestView(uri span.URI) (*View, error) {
+ if len(s.views) == 0 {
+ return nil, errors.Errorf("no views in the session")
+ }
+ // we need to find the best view for this file
+ var longest *View
+ for _, view := range s.views {
+ if longest != nil && len(longest.Folder()) > len(view.Folder()) {
+ continue
+ }
+ if view.contains(uri) {
+ longest = view
+ }
+ }
+ if longest != nil {
+ return longest, nil
+ }
+ // Try our best to return a view that knows the file.
+ for _, view := range s.views {
+ if view.knownFile(uri) {
+ return view, nil
+ }
+ }
+ // TODO: are there any more heuristics we can use?
+ return s.views[0], nil
+}
+
+func (s *Session) removeView(ctx context.Context, view *View) error {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ i, err := s.dropView(ctx, view)
+ if err != nil {
+ return err
+ }
+ // delete this view... we don't care about order but we do want to make
+ // sure we can garbage collect the view
+ s.views[i] = s.views[len(s.views)-1]
+ s.views[len(s.views)-1] = nil
+ s.views = s.views[:len(s.views)-1]
+ return nil
+}
+
+func (s *Session) updateView(ctx context.Context, view *View, options *source.Options) (*View, error) {
+ s.viewMu.Lock()
+ defer s.viewMu.Unlock()
+ i, err := s.dropView(ctx, view)
+ if err != nil {
+ return nil, err
+ }
+ // Preserve the snapshot ID if we are recreating the view.
+ view.snapshotMu.Lock()
+ snapshotID := view.snapshot.id
+ view.snapshotMu.Unlock()
+ v, _, release, err := s.createView(ctx, view.name, view.folder, options, snapshotID)
+ release()
+ if err != nil {
+ // we have dropped the old view, but could not create the new one
+ // this should not happen and is very bad, but we still need to clean
+ // up the view array if it happens
+ s.views[i] = s.views[len(s.views)-1]
+ s.views[len(s.views)-1] = nil
+ s.views = s.views[:len(s.views)-1]
+ return nil, err
+ }
+ // substitute the new view into the array where the old view was
+ s.views[i] = v
+ return v, nil
+}
+
+func (s *Session) dropView(ctx context.Context, v *View) (int, error) {
+ // we always need to drop the view map
+ s.viewMap = make(map[span.URI]*View)
+ for i := range s.views {
+ if v == s.views[i] {
+ // we found the view, drop it and return the index it was found at
+ s.views[i] = nil
+ v.shutdown(ctx)
+ return i, nil
+ }
+ }
+ return -1, errors.Errorf("view %s for %v not found", v.Name(), v.Folder())
+}
+
+func (s *Session) ModifyFiles(ctx context.Context, changes []source.FileModification) error {
+ _, _, releases, _, err := s.DidModifyFiles(ctx, changes)
+ for _, release := range releases {
+ release()
+ }
+ return err
+}
+
+func (s *Session) DidModifyFiles(ctx context.Context, changes []source.FileModification) (map[span.URI]source.View, map[source.View]source.Snapshot, []func(), []span.URI, error) {
+ views := make(map[*View]map[span.URI]source.VersionedFileHandle)
+ bestViews := map[span.URI]source.View{}
+ // Keep track of deleted files so that we can clear their diagnostics.
+ // A file might be re-created after deletion, so only mark files that
+ // have truly been deleted.
+ deletions := map[span.URI]struct{}{}
+
+ overlays, err := s.updateOverlays(ctx, changes)
+ if err != nil {
+ return nil, nil, nil, nil, err
+ }
+ var forceReloadMetadata bool
+ for _, c := range changes {
+ if c.Action == source.InvalidateMetadata {
+ forceReloadMetadata = true
+ }
+
+ // Build the list of affected views.
+ bestView, err := s.viewOf(c.URI)
+ if err != nil {
+ return nil, nil, nil, nil, err
+ }
+ bestViews[c.URI] = bestView
+
+ var changedViews []*View
+ for _, view := range s.views {
+ // Don't propagate changes that are outside of the view's scope
+ // or knowledge.
+ if !view.relevantChange(c) {
+ continue
+ }
+ changedViews = append(changedViews, view)
+ }
+ // If no view matched the change, assign it to the best view.
+ if len(changedViews) == 0 {
+ changedViews = append(changedViews, bestView)
+ }
+
+ // Apply the changes to all affected views.
+ for _, view := range changedViews {
+ // Make sure that the file is added to the view.
+ if _, err := view.getFile(c.URI); err != nil {
+ return nil, nil, nil, nil, err
+ }
+ if _, ok := views[view]; !ok {
+ views[view] = make(map[span.URI]source.VersionedFileHandle)
+ }
+ var (
+ fh source.VersionedFileHandle
+ ok bool
+ )
+ if fh, ok = overlays[c.URI]; ok {
+ views[view][c.URI] = fh
+ delete(deletions, c.URI)
+ } else {
+ fsFile, err := s.cache.getFile(ctx, c.URI)
+ if err != nil {
+ return nil, nil, nil, nil, err
+ }
+ fh = &closedFile{fsFile}
+ views[view][c.URI] = fh
+ if _, err := fh.Read(); err != nil {
+ deletions[c.URI] = struct{}{}
+ }
+ }
+ }
+ }
+
+ snapshots := map[source.View]source.Snapshot{}
+ var releases []func()
+ for view, uris := range views {
+ snapshot, release := view.invalidateContent(ctx, uris, forceReloadMetadata)
+ snapshots[view] = snapshot
+ releases = append(releases, release)
+ }
+ var deletionsSlice []span.URI
+ for uri := range deletions {
+ deletionsSlice = append(deletionsSlice, uri)
+ }
+ return bestViews, snapshots, releases, deletionsSlice, nil
+}
+
+func (s *Session) updateOverlays(ctx context.Context, changes []source.FileModification) (map[span.URI]*overlay, error) {
+ s.overlayMu.Lock()
+ defer s.overlayMu.Unlock()
+
+ for _, c := range changes {
+ // Don't update overlays for metadata invalidations.
+ if c.Action == source.InvalidateMetadata {
+ continue
+ }
+
+ o, ok := s.overlays[c.URI]
+
+ // If the file is not opened in an overlay and the change is on disk,
+ // there's no need to update an overlay. If there is an overlay, we
+ // may need to update the overlay's saved value.
+ if !ok && c.OnDisk {
+ continue
+ }
+
+ // Determine the file kind on open, otherwise, assume it has been cached.
+ var kind source.FileKind
+ switch c.Action {
+ case source.Open:
+ kind = source.DetectLanguage(c.LanguageID, c.URI.Filename())
+ default:
+ if !ok {
+ return nil, errors.Errorf("updateOverlays: modifying unopened overlay %v", c.URI)
+ }
+ kind = o.kind
+ }
+ if kind == source.UnknownKind {
+ return nil, errors.Errorf("updateOverlays: unknown file kind for %s", c.URI)
+ }
+
+ // Closing a file just deletes its overlay.
+ if c.Action == source.Close {
+ delete(s.overlays, c.URI)
+ continue
+ }
+
+ // If the file is on disk, check if its content is the same as in the
+ // overlay. Saves and on-disk file changes don't come with the file's
+ // content.
+ text := c.Text
+ if text == nil && (c.Action == source.Save || c.OnDisk) {
+ if !ok {
+ return nil, fmt.Errorf("no known content for overlay for %s", c.Action)
+ }
+ text = o.text
+ }
+ // On-disk changes don't come with versions.
+ version := c.Version
+ if c.OnDisk {
+ version = o.version
+ }
+ hash := hashContents(text)
+ var sameContentOnDisk bool
+ switch c.Action {
+ case source.Delete:
+ // Do nothing. sameContentOnDisk should be false.
+ case source.Save:
+ // Make sure the version and content (if present) is the same.
+ if o.version != version {
+ return nil, errors.Errorf("updateOverlays: saving %s at version %v, currently at %v", c.URI, c.Version, o.version)
+ }
+ if c.Text != nil && o.hash != hash {
+ return nil, errors.Errorf("updateOverlays: overlay %s changed on save", c.URI)
+ }
+ sameContentOnDisk = true
+ default:
+ fh, err := s.cache.getFile(ctx, c.URI)
+ if err != nil {
+ return nil, err
+ }
+ _, readErr := fh.Read()
+ sameContentOnDisk = (readErr == nil && fh.FileIdentity().Hash == hash)
+ }
+ o = &overlay{
+ session: s,
+ uri: c.URI,
+ version: version,
+ text: text,
+ kind: kind,
+ hash: hash,
+ saved: sameContentOnDisk,
+ }
+ s.overlays[c.URI] = o
+ }
+
+ // Get the overlays for each change while the session's overlay map is
+ // locked.
+ overlays := make(map[span.URI]*overlay)
+ for _, c := range changes {
+ if o, ok := s.overlays[c.URI]; ok {
+ overlays[c.URI] = o
+ }
+ }
+ return overlays, nil
+}
+
+func (s *Session) GetFile(ctx context.Context, uri span.URI) (source.FileHandle, error) {
+ if overlay := s.readOverlay(uri); overlay != nil {
+ return overlay, nil
+ }
+ // Fall back to the cache-level file system.
+ return s.cache.getFile(ctx, uri)
+}
+
+func (s *Session) readOverlay(uri span.URI) *overlay {
+ s.overlayMu.Lock()
+ defer s.overlayMu.Unlock()
+
+ if overlay, ok := s.overlays[uri]; ok {
+ return overlay
+ }
+ return nil
+}
+
+func (s *Session) Overlays() []source.Overlay {
+ s.overlayMu.Lock()
+ defer s.overlayMu.Unlock()
+
+ overlays := make([]source.Overlay, 0, len(s.overlays))
+ for _, overlay := range s.overlays {
+ overlays = append(overlays, overlay)
+ }
+ return overlays
+}
projects / dotfiles / .git / blobdiff