| // 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" |
| |
| "golang.org/x/tools/internal/lsp/source" |
| "golang.org/x/tools/internal/span" |
| ) |
| |
| type overlay struct { |
| session *session |
| uri span.URI |
| data []byte |
| hash string |
| version float64 |
| kind source.FileKind |
| |
| // sameContentOnDisk is true if a file has been saved on disk, |
| // and therefore does not need to be part of the overlay sent to go/packages. |
| sameContentOnDisk bool |
| } |
| |
| func (o *overlay) FileSystem() source.FileSystem { |
| return o.session |
| } |
| |
| func (o *overlay) Identity() source.FileIdentity { |
| return source.FileIdentity{ |
| URI: o.uri, |
| Identifier: o.hash, |
| Version: o.version, |
| Kind: o.kind, |
| } |
| } |
| func (o *overlay) Read(ctx context.Context) ([]byte, string, error) { |
| return o.data, o.hash, nil |
| } |
| |
| func (s *session) setOverlay(f source.File, version float64, data []byte) { |
| s.overlayMu.Lock() |
| defer func() { |
| s.overlayMu.Unlock() |
| s.filesWatchMap.Notify(f.URI(), source.Change) |
| }() |
| |
| if data == nil { |
| delete(s.overlays, f.URI()) |
| return |
| } |
| |
| s.overlays[f.URI()] = &overlay{ |
| session: s, |
| uri: f.URI(), |
| kind: f.Kind(), |
| data: data, |
| hash: hashContents(data), |
| version: version, |
| } |
| } |
| |
| func (s *session) clearOverlay(uri span.URI) { |
| s.overlayMu.Lock() |
| defer s.overlayMu.Unlock() |
| |
| delete(s.overlays, uri) |
| } |
| |
| // openOverlay adds the file content to the overlay. |
| // It also checks if the provided content is equivalent to the file's content on disk. |
| func (s *session) openOverlay(ctx context.Context, uri span.URI, kind source.FileKind, version float64, data []byte) { |
| s.overlayMu.Lock() |
| defer func() { |
| s.overlayMu.Unlock() |
| s.filesWatchMap.Notify(uri, source.Open) |
| }() |
| s.overlays[uri] = &overlay{ |
| session: s, |
| uri: uri, |
| kind: kind, |
| data: data, |
| hash: hashContents(data), |
| version: version, |
| } |
| // If the file is on disk, check if its content is the same as the overlay. |
| if _, hash, err := s.cache.GetFile(uri, kind).Read(ctx); err == nil { |
| if hash == s.overlays[uri].hash { |
| s.overlays[uri].sameContentOnDisk = true |
| } |
| } |
| } |
| |
| func (s *session) readOverlay(uri span.URI) *overlay { |
| s.overlayMu.Lock() |
| defer s.overlayMu.Unlock() |
| |
| // We might have the content saved in an overlay. |
| if overlay, ok := s.overlays[uri]; ok { |
| return overlay |
| } |
| return nil |
| } |
| |
| func (s *session) buildOverlay() map[string][]byte { |
| s.overlayMu.Lock() |
| defer s.overlayMu.Unlock() |
| |
| overlays := make(map[string][]byte) |
| for uri, overlay := range s.overlays { |
| if overlay.sameContentOnDisk { |
| continue |
| } |
| overlays[uri.Filename()] = overlay.data |
| } |
| return overlays |
| } |