clang-tools  10.0.0
ClangdLSPServer.h
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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 "Context.h"
14 #include "DraftStore.h"
15 #include "Features.inc"
16 #include "FindSymbols.h"
18 #include "Path.h"
19 #include "Protocol.h"
20 #include "Transport.h"
21 #include "clang/Tooling/Core/Replacement.h"
22 #include "llvm/ADT/Optional.h"
23 #include <memory>
24 
25 namespace clang {
26 namespace clangd {
27 
28 class SymbolIndex;
29 
30 /// This class exposes ClangdServer's capabilities via Language Server Protocol.
31 ///
32 /// MessageHandler binds the implemented LSP methods (e.g. onInitialize) to
33 /// corresponding JSON-RPC methods ("initialize").
34 /// The server also supports $/cancelRequest (MessageHandler provides this).
36 public:
37  /// If \p CompileCommandsDir has a value, compile_commands.json will be
38  /// loaded only from \p CompileCommandsDir. Otherwise, clangd will look
39  /// for compile_commands.json in all parent directories of each file.
40  /// If UseDirBasedCDB is false, compile commands are not read from disk.
41  // FIXME: Clean up signature around CDBs.
42  ClangdLSPServer(Transport &Transp, const FileSystemProvider &FSProvider,
43  const clangd::CodeCompleteOptions &CCOpts,
44  llvm::Optional<Path> CompileCommandsDir, bool UseDirBasedCDB,
45  llvm::Optional<OffsetEncoding> ForcedOffsetEncoding,
46  const ClangdServer::Options &Opts);
47  /// The destructor blocks on any outstanding background tasks.
49 
50  /// Run LSP server loop, communicating with the Transport provided in the
51  /// constructor. This method must not be executed more than once.
52  ///
53  /// \return Whether we shut down cleanly with a 'shutdown' -> 'exit' sequence.
54  bool run();
55 
56 private:
57  // Implement DiagnosticsConsumer.
58  void onDiagnosticsReady(PathRef File, std::vector<Diag> Diagnostics) override;
59  void onFileUpdated(PathRef File, const TUStatus &Status) override;
60  void
61  onHighlightingsReady(PathRef File,
62  std::vector<HighlightingToken> Highlightings) override;
63 
64  // LSP methods. Notifications have signature void(const Params&).
65  // Calls have signature void(const Params&, Callback<Response>).
66  void onInitialize(const InitializeParams &, Callback<llvm::json::Value>);
67  void onShutdown(const ShutdownParams &, Callback<std::nullptr_t>);
68  void onSync(const NoParams &, Callback<std::nullptr_t>);
69  void onDocumentDidOpen(const DidOpenTextDocumentParams &);
70  void onDocumentDidChange(const DidChangeTextDocumentParams &);
71  void onDocumentDidClose(const DidCloseTextDocumentParams &);
72  void onDocumentOnTypeFormatting(const DocumentOnTypeFormattingParams &,
73  Callback<std::vector<TextEdit>>);
74  void onDocumentRangeFormatting(const DocumentRangeFormattingParams &,
75  Callback<std::vector<TextEdit>>);
76  void onDocumentFormatting(const DocumentFormattingParams &,
77  Callback<std::vector<TextEdit>>);
78  // The results are serialized 'vector<DocumentSymbol>' if
79  // SupportsHierarchicalDocumentSymbol is true and 'vector<SymbolInformation>'
80  // otherwise.
81  void onDocumentSymbol(const DocumentSymbolParams &,
83  void onCodeAction(const CodeActionParams &, Callback<llvm::json::Value>);
84  void onCompletion(const CompletionParams &, Callback<CompletionList>);
85  void onSignatureHelp(const TextDocumentPositionParams &,
87  void onGoToDeclaration(const TextDocumentPositionParams &,
88  Callback<std::vector<Location>>);
89  void onGoToDefinition(const TextDocumentPositionParams &,
90  Callback<std::vector<Location>>);
91  void onReference(const ReferenceParams &, Callback<std::vector<Location>>);
92  void onSwitchSourceHeader(const TextDocumentIdentifier &,
93  Callback<llvm::Optional<URIForFile>>);
94  void onDocumentHighlight(const TextDocumentPositionParams &,
95  Callback<std::vector<DocumentHighlight>>);
96  void onFileEvent(const DidChangeWatchedFilesParams &);
97  void onCommand(const ExecuteCommandParams &, Callback<llvm::json::Value>);
98  void onWorkspaceSymbol(const WorkspaceSymbolParams &,
99  Callback<std::vector<SymbolInformation>>);
100  void onPrepareRename(const TextDocumentPositionParams &,
101  Callback<llvm::Optional<Range>>);
102  void onRename(const RenameParams &, Callback<WorkspaceEdit>);
103  void onHover(const TextDocumentPositionParams &,
104  Callback<llvm::Optional<Hover>>);
105  void onTypeHierarchy(const TypeHierarchyParams &,
106  Callback<llvm::Optional<TypeHierarchyItem>>);
107  void onResolveTypeHierarchy(const ResolveTypeHierarchyItemParams &,
108  Callback<llvm::Optional<TypeHierarchyItem>>);
109  void onChangeConfiguration(const DidChangeConfigurationParams &);
110  void onSymbolInfo(const TextDocumentPositionParams &,
111  Callback<std::vector<SymbolDetails>>);
112  void onSelectionRange(const SelectionRangeParams &,
113  Callback<std::vector<SelectionRange>>);
114  void onDocumentLink(const DocumentLinkParams &,
115  Callback<std::vector<DocumentLink>>);
116 
117  std::vector<Fix> getFixes(StringRef File, const clangd::Diagnostic &D);
118 
119  /// Checks if completion request should be ignored. We need this due to the
120  /// limitation of the LSP. Per LSP, a client sends requests for all "trigger
121  /// character" we specify, but for '>' and ':' we need to check they actually
122  /// produce '->' and '::', respectively.
123  bool shouldRunCompletion(const CompletionParams &Params) const;
124 
125  /// Forces a reparse of all currently opened files. As a result, this method
126  /// may be very expensive. This method is normally called when the
127  /// compilation database is changed.
128  void reparseOpenedFiles();
129  void applyConfiguration(const ConfigurationSettings &Settings);
130 
131  /// Sends a "publishSemanticHighlighting" notification to the LSP client.
132  void publishSemanticHighlighting(SemanticHighlightingParams Params);
133 
134  /// Sends a "publishDiagnostics" notification to the LSP client.
135  void publishDiagnostics(const URIForFile &File,
136  std::vector<clangd::Diagnostic> Diagnostics);
137 
138  /// Since initialization of CDBs and ClangdServer is done lazily, the
139  /// following context captures the one used while creating ClangdLSPServer and
140  /// passes it to above mentioned object instances to make sure they share the
141  /// same state.
142  Context BackgroundContext;
143 
144  /// Used to indicate that the 'shutdown' request was received from the
145  /// Language Server client.
146  bool ShutdownRequestReceived = false;
147 
148  /// Used to indicate the ClangdLSPServer is being destroyed.
149  std::atomic<bool> IsBeingDestroyed = {false};
150 
151  std::mutex FixItsMutex;
152  typedef std::map<clangd::Diagnostic, std::vector<Fix>, LSPDiagnosticCompare>
153  DiagnosticToReplacementMap;
154  /// Caches FixIts per file and diagnostics
155  llvm::StringMap<DiagnosticToReplacementMap> FixItsMap;
156  std::mutex HighlightingsMutex;
157  llvm::StringMap<std::vector<HighlightingToken>> FileToHighlightings;
158 
159  // Most code should not deal with Transport directly.
160  // MessageHandler deals with incoming messages, use call() etc for outgoing.
161  clangd::Transport &Transp;
162  class MessageHandler;
163  std::unique_ptr<MessageHandler> MsgHandler;
164  std::mutex TranspWriter;
165 
166  template <typename Response>
167  void call(StringRef Method, llvm::json::Value Params, Callback<Response> CB) {
168  // Wrap the callback with LSP conversion and error-handling.
169  auto HandleReply =
170  [CB = std::move(CB), Ctx = Context::current().clone()](
171  llvm::Expected<llvm::json::Value> RawResponse) mutable {
172  Response Rsp;
173  if (!RawResponse) {
174  CB(RawResponse.takeError());
175  } else if (fromJSON(*RawResponse, Rsp)) {
176  CB(std::move(Rsp));
177  } else {
178  elog("Failed to decode {0} response", *RawResponse);
179  CB(llvm::make_error<LSPError>("failed to decode reponse",
181  }
182  };
183  callRaw(Method, std::move(Params), std::move(HandleReply));
184  }
185  void callRaw(StringRef Method, llvm::json::Value Params,
187  void notify(StringRef Method, llvm::json::Value Params);
188 
190  /// Options used for code completion
192  /// Options used for diagnostics.
193  ClangdDiagnosticOptions DiagOpts;
194  /// The supported kinds of the client.
195  SymbolKindBitset SupportedSymbolKinds;
196  /// The supported completion item kinds of the client.
197  CompletionItemKindBitset SupportedCompletionItemKinds;
198  /// Whether the client supports CodeAction response objects.
199  bool SupportsCodeAction = false;
200  /// From capabilities of textDocument/documentSymbol.
201  bool SupportsHierarchicalDocumentSymbol = false;
202  /// Whether the client supports showing file status.
203  bool SupportFileStatus = false;
204  /// Which kind of markup should we use in textDocument/hover responses.
205  MarkupKind HoverContentFormat = MarkupKind::PlainText;
206  /// Whether the client supports offsets for parameter info labels.
207  bool SupportsOffsetsInSignatureHelp = false;
208  // Store of the current versions of the open documents.
209  DraftStore DraftMgr;
210 
211  // The CDB is created by the "initialize" LSP method.
212  bool UseDirBasedCDB; // FIXME: make this a capability.
213  llvm::Optional<Path> CompileCommandsDir; // FIXME: merge with capability?
214  std::unique_ptr<GlobalCompilationDatabase> BaseCDB;
215  // CDB is BaseCDB plus any commands overridden via LSP extensions.
216  llvm::Optional<OverlayCDB> CDB;
217  ClangdServer::Options ClangdServerOpts;
218  llvm::Optional<OffsetEncoding> NegotiatedOffsetEncoding;
219  // The ClangdServer is created by the "initialize" LSP method.
220  llvm::Optional<ClangdServer> Server;
221 };
222 } // namespace clangd
223 } // namespace clang
224 
225 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_CLANGDLSPSERVER_H
Exact commands are not specified in the protocol so we define the ones supported by Clangd here...
Definition: Protocol.h:746
bool run()
Run LSP server loop, communicating with the Transport provided in the constructor.
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:23
llvm::unique_function< void(llvm::Expected< T >)> Callback
A Callback<T> is a void function that accepts Expected<T>.
Definition: Function.h:28
std::bitset< CompletionItemKindMax+1 > CompletionItemKindBitset
Definition: Protocol.h:293
void elog(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:56
MockFSProvider FSProvider
Context Ctx
Parameters for the semantic highlighting (server-side) push notification.
Definition: Protocol.h:1230
Clangd extension: parameters configurable at any time, via the workspace/didChangeConfiguration notif...
Definition: Protocol.h:445
Context clone() const
Clone this context object.
Definition: Context.cpp:20
static const Context & current()
Returns the context for the current thread, creating it if needed.
Definition: Context.cpp:27
A context is an immutable container for per-request data that must be propagated through layers that ...
Definition: Context.h:69
~ClangdLSPServer()
The destructor blocks on any outstanding background tasks.
bool fromJSON(const llvm::json::Value &Parameters, FuzzyFindRequest &Request)
Definition: Index.cpp:34
A LSP-specific comparator used to find diagnostic in a container like std:map.
Definition: Protocol.h:687
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
std::bitset< SymbolKindMax+1 > SymbolKindBitset
Definition: Protocol.h:331
ClangdServer Server
The type hierarchy params is an extension of the TextDocumentPositionsParams with optional properties...
Definition: Protocol.h:1127
A thread-safe container for files opened in a workspace, addressed by filenames.
Definition: DraftStore.h:26
The parameters of a Workspace Symbol Request.
Definition: Protocol.h:866
Parameters for the typeHierarchy/resolve request.
Definition: Protocol.h:1183
Parameters for the document link request.
Definition: Protocol.h:1261
This class exposes ClangdServer&#39;s capabilities via Language Server Protocol.
ClangdLSPServer(Transport &Transp, const FileSystemProvider &FSProvider, const clangd::CodeCompleteOptions &CCOpts, llvm::Optional< Path > CompileCommandsDir, bool UseDirBasedCDB, llvm::Optional< OffsetEncoding > ForcedOffsetEncoding, const ClangdServer::Options &Opts)
If CompileCommandsDir has a value, compile_commands.json will be loaded only from CompileCommandsDir...