1 //===--- ClangdLSPServer.h - LSP server --------------------------*- C++-*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_CLANGDLSPSERVER_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_CLANGDLSPSERVER_H
11 
12 #include "ClangdServer.h"
13 #include "DraftStore.h"
14 #include "Features.inc"
15 #include "FindSymbols.h"
16 #include "GlobalCompilationDatabase.h"
17 #include "Path.h"
18 #include "Protocol.h"
19 #include "Transport.h"
20 #include "clang/Tooling/Core/Replacement.h"
21 #include "llvm/ADT/Optional.h"
22 #include <memory>
23 
24 namespace clang {
25 namespace clangd {
26 
27 class SymbolIndex;
28 
29 /// This class exposes ClangdServer's capabilities via Language Server Protocol.
30 ///
31 /// MessageHandler binds the implemented LSP methods (e.g. onInitialize) to
32 /// corresponding JSON-RPC methods ("initialize").
33 /// The server also supports $/cancelRequest (MessageHandler provides this).
34 class ClangdLSPServer : private DiagnosticsConsumer {
35 public:
36   /// If \p CompileCommandsDir has a value, compile_commands.json will be
37   /// loaded only from \p CompileCommandsDir. Otherwise, clangd will look
38   /// for compile_commands.json in all parent directories of each file.
39   /// If UseDirBasedCDB is false, compile commands are not read from disk.
40   // FIXME: Clean up signature around CDBs.
41   ClangdLSPServer(Transport &Transp, const FileSystemProvider &FSProvider,
42                   const clangd::CodeCompleteOptions &CCOpts,
43                   llvm::Optional<Path> CompileCommandsDir, bool UseDirBasedCDB,
44                   llvm::Optional<OffsetEncoding> ForcedOffsetEncoding,
45                   const ClangdServer::Options &Opts);
46   ~ClangdLSPServer();
47 
48   /// Run LSP server loop, communicating with the Transport provided in the
49   /// constructor. This method must not be executed more than once.
50   ///
51   /// \return Whether we shut down cleanly with a 'shutdown' -> 'exit' sequence.
52   bool run();
53 
54 private:
55   // Implement DiagnosticsConsumer.
56   void onDiagnosticsReady(PathRef File, std::vector<Diag> Diagnostics) override;
57   void onFileUpdated(PathRef File, const TUStatus &Status) override;
58   void
59   onHighlightingsReady(PathRef File,
60                        std::vector<HighlightingToken> Highlightings) override;
61 
62   // LSP methods. Notifications have signature void(const Params&).
63   // Calls have signature void(const Params&, Callback<Response>).
64   void onInitialize(const InitializeParams &, Callback<llvm::json::Value>);
65   void onShutdown(const ShutdownParams &, Callback<std::nullptr_t>);
66   void onSync(const NoParams &, Callback<std::nullptr_t>);
67   void onDocumentDidOpen(const DidOpenTextDocumentParams &);
68   void onDocumentDidChange(const DidChangeTextDocumentParams &);
69   void onDocumentDidClose(const DidCloseTextDocumentParams &);
70   void onDocumentOnTypeFormatting(const DocumentOnTypeFormattingParams &,
71                                   Callback<std::vector<TextEdit>>);
72   void onDocumentRangeFormatting(const DocumentRangeFormattingParams &,
73                                  Callback<std::vector<TextEdit>>);
74   void onDocumentFormatting(const DocumentFormattingParams &,
75                             Callback<std::vector<TextEdit>>);
76   // The results are serialized 'vector<DocumentSymbol>' if
77   // SupportsHierarchicalDocumentSymbol is true and 'vector<SymbolInformation>'
78   // otherwise.
79   void onDocumentSymbol(const DocumentSymbolParams &,
80                         Callback<llvm::json::Value>);
81   void onCodeAction(const CodeActionParams &, Callback<llvm::json::Value>);
82   void onCompletion(const CompletionParams &, Callback<CompletionList>);
83   void onSignatureHelp(const TextDocumentPositionParams &,
84                        Callback<SignatureHelp>);
85   void onGoToDeclaration(const TextDocumentPositionParams &,
86                          Callback<std::vector<Location>>);
87   void onGoToDefinition(const TextDocumentPositionParams &,
88                         Callback<std::vector<Location>>);
89   void onReference(const ReferenceParams &, Callback<std::vector<Location>>);
90   void onSwitchSourceHeader(const TextDocumentIdentifier &,
91                             Callback<llvm::Optional<URIForFile>>);
92   void onDocumentHighlight(const TextDocumentPositionParams &,
93                            Callback<std::vector<DocumentHighlight>>);
94   void onFileEvent(const DidChangeWatchedFilesParams &);
95   void onCommand(const ExecuteCommandParams &, Callback<llvm::json::Value>);
96   void onWorkspaceSymbol(const WorkspaceSymbolParams &,
97                          Callback<std::vector<SymbolInformation>>);
98   void onRename(const RenameParams &, Callback<WorkspaceEdit>);
99   void onHover(const TextDocumentPositionParams &,
100                Callback<llvm::Optional<Hover>>);
101   void onTypeHierarchy(const TypeHierarchyParams &,
102                        Callback<llvm::Optional<TypeHierarchyItem>>);
103   void onResolveTypeHierarchy(const ResolveTypeHierarchyItemParams &,
104                               Callback<llvm::Optional<TypeHierarchyItem>>);
105   void onChangeConfiguration(const DidChangeConfigurationParams &);
106   void onSymbolInfo(const TextDocumentPositionParams &,
107                     Callback<std::vector<SymbolDetails>>);
108 
109   std::vector<Fix> getFixes(StringRef File, const clangd::Diagnostic &D);
110 
111   /// Checks if completion request should be ignored. We need this due to the
112   /// limitation of the LSP. Per LSP, a client sends requests for all "trigger
113   /// character" we specify, but for '>' and ':' we need to check they actually
114   /// produce '->' and '::', respectively.
115   bool shouldRunCompletion(const CompletionParams &Params) const;
116 
117   /// Forces a reparse of all currently opened files.  As a result, this method
118   /// may be very expensive.  This method is normally called when the
119   /// compilation database is changed.
120   void reparseOpenedFiles();
121   void applyConfiguration(const ConfigurationSettings &Settings);
122 
123   /// Sends a "publishSemanticHighlighting" notification to the LSP client.
124   void publishSemanticHighlighting(SemanticHighlightingParams Params);
125 
126   /// Sends a "publishDiagnostics" notification to the LSP client.
127   void publishDiagnostics(const URIForFile &File,
128                           std::vector<clangd::Diagnostic> Diagnostics);
129 
130   /// Used to indicate that the 'shutdown' request was received from the
131   /// Language Server client.
132   bool ShutdownRequestReceived = false;
133 
134   std::mutex FixItsMutex;
135   typedef std::map<clangd::Diagnostic, std::vector<Fix>, LSPDiagnosticCompare>
136       DiagnosticToReplacementMap;
137   /// Caches FixIts per file and diagnostics
138   llvm::StringMap<DiagnosticToReplacementMap> FixItsMap;
139 
140   // Most code should not deal with Transport directly.
141   // MessageHandler deals with incoming messages, use call() etc for outgoing.
142   clangd::Transport &Transp;
143   class MessageHandler;
144   std::unique_ptr<MessageHandler> MsgHandler;
145   std::atomic<int> NextCallID = {0};
146   std::mutex TranspWriter;
147   void call(StringRef Method, llvm::json::Value Params);
148   void notify(StringRef Method, llvm::json::Value Params);
149 
150   const FileSystemProvider &FSProvider;
151   /// Options used for code completion
152   clangd::CodeCompleteOptions CCOpts;
153   /// Options used for diagnostics.
154   ClangdDiagnosticOptions DiagOpts;
155   /// The supported kinds of the client.
156   SymbolKindBitset SupportedSymbolKinds;
157   /// The supported completion item kinds of the client.
158   CompletionItemKindBitset SupportedCompletionItemKinds;
159   /// Whether the client supports CodeAction response objects.
160   bool SupportsCodeAction = false;
161   /// From capabilities of textDocument/documentSymbol.
162   bool SupportsHierarchicalDocumentSymbol = false;
163   /// Whether the client supports showing file status.
164   bool SupportFileStatus = false;
165   /// Which kind of markup should we use in textDocument/hover responses.
166   MarkupKind HoverContentFormat = MarkupKind::PlainText;
167   /// Whether the client supports offsets for parameter info labels.
168   bool SupportsOffsetsInSignatureHelp = false;
169   // Store of the current versions of the open documents.
170   DraftStore DraftMgr;
171 
172   // The CDB is created by the "initialize" LSP method.
173   bool UseDirBasedCDB;                     // FIXME: make this a capability.
174   llvm::Optional<Path> CompileCommandsDir; // FIXME: merge with capability?
175   std::unique_ptr<GlobalCompilationDatabase> BaseCDB;
176   // CDB is BaseCDB plus any comands overridden via LSP extensions.
177   llvm::Optional<OverlayCDB> CDB;
178   // The ClangdServer is created by the "initialize" LSP method.
179   // It is destroyed before run() returns, to ensure worker threads exit.
180   ClangdServer::Options ClangdServerOpts;
181   llvm::Optional<ClangdServer> Server;
182   llvm::Optional<OffsetEncoding> NegotiatedOffsetEncoding;
183 };
184 } // namespace clangd
185 } // namespace clang
186 
187 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_CLANGDLSPSERVER_H
188