clang-tools  8.0.0
GlobalCompilationDatabase.h
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1 //===--- GlobalCompilationDatabase.h -----------------------------*- C++-*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_GLOBALCOMPILATIONDATABASE_H
11 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_GLOBALCOMPILATIONDATABASE_H
12 
13 #include "Function.h"
14 #include "Path.h"
15 #include "llvm/ADT/Optional.h"
16 #include "llvm/ADT/StringMap.h"
17 #include <memory>
18 #include <mutex>
19 #include <vector>
20 
21 namespace clang {
22 
23 namespace tooling {
24 class CompilationDatabase;
25 struct CompileCommand;
26 } // namespace tooling
27 
28 namespace clangd {
29 
30 class Logger;
31 
32 struct ProjectInfo {
33  // The directory in which the compilation database was discovered.
34  // Empty if directory-based compilation database discovery was not used.
35  std::string SourceRoot;
36 };
37 
38 /// Provides compilation arguments used for parsing C and C++ files.
40 public:
41  virtual ~GlobalCompilationDatabase() = default;
42 
43  /// If there are any known-good commands for building this file, returns one.
44  /// If the ProjectInfo pointer is set, it will also be populated.
45  virtual llvm::Optional<tooling::CompileCommand>
46  getCompileCommand(PathRef File, ProjectInfo * = nullptr) const = 0;
47 
48  /// Makes a guess at how to build a file.
49  /// The default implementation just runs clang on the file.
50  /// Clangd should treat the results as unreliable.
51  virtual tooling::CompileCommand getFallbackCommand(PathRef File) const;
52 
54  /// The callback is notified when files may have new compile commands.
55  /// The argument is a list of full file paths.
56  CommandChanged::Subscription watch(CommandChanged::Listener L) const {
57  return OnCommandChanged.observe(std::move(L));
58  }
59 
60 protected:
62 };
63 
64 /// Gets compile args from tooling::CompilationDatabases built for parent
65 /// directories.
67  : public GlobalCompilationDatabase {
68 public:
70  llvm::Optional<Path> CompileCommandsDir);
72 
73  /// Scans File's parents looking for compilation databases.
74  /// Any extra flags will be added.
75  llvm::Optional<tooling::CompileCommand>
76  getCompileCommand(PathRef File, ProjectInfo * = nullptr) const override;
77 
78 private:
79  tooling::CompilationDatabase *getCDBForFile(PathRef File,
80  ProjectInfo *) const;
81  std::pair<tooling::CompilationDatabase *, /*Cached*/ bool>
82  getCDBInDirLocked(PathRef File) const;
83 
84  mutable std::mutex Mutex;
85  /// Caches compilation databases loaded from directories(keys are
86  /// directories).
87  mutable llvm::StringMap<std::unique_ptr<clang::tooling::CompilationDatabase>>
88  CompilationDatabases;
89 
90  /// Used for command argument pointing to folder where compile_commands.json
91  /// is located.
92  llvm::Optional<Path> CompileCommandsDir;
93 };
94 
95 /// Wraps another compilation database, and supports overriding the commands
96 /// using an in-memory mapping.
98 public:
99  // Base may be null, in which case no entries are inherited.
100  // FallbackFlags are added to the fallback compile command.
102  std::vector<std::string> FallbackFlags = {},
103  llvm::Optional<std::string> ResourceDir = llvm::None);
104 
105  llvm::Optional<tooling::CompileCommand>
106  getCompileCommand(PathRef File, ProjectInfo * = nullptr) const override;
107  tooling::CompileCommand getFallbackCommand(PathRef File) const override;
108 
109  /// Sets or clears the compilation command for a particular file.
110  void
111  setCompileCommand(PathRef File,
112  llvm::Optional<tooling::CompileCommand> CompilationCommand);
113 
114 private:
115  mutable std::mutex Mutex;
116  llvm::StringMap<tooling::CompileCommand> Commands; /* GUARDED_BY(Mut) */
117  const GlobalCompilationDatabase *Base;
118  std::string ResourceDir;
119  std::vector<std::string> FallbackFlags;
120  CommandChanged::Subscription BaseChanged;
121 };
122 
123 } // namespace clangd
124 } // namespace clang
125 
126 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_GLOBALCOMPILATIONDATABASE_H
std::function< void(const std::vector< std::string > &)> Listener
Definition: Function.h:91
static cl::list< std::string > Commands("c", cl::desc("Specify command to run"), cl::value_desc("command"), cl::cat(ClangQueryCategory))
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:24
Provides compilation arguments used for parsing C and C++ files.
static llvm::cl::opt< Path > ResourceDir("resource-dir", llvm::cl::desc("Directory for system clang headers"), llvm::cl::init(""), llvm::cl::Hidden)
CommandChanged::Subscription watch(CommandChanged::Listener L) const
The callback is notified when files may have new compile commands.
Gets compile args from tooling::CompilationDatabases built for parent directories.
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Wraps another compilation database, and supports overriding the commands using an in-memory mapping...
static llvm::cl::opt< Path > CompileCommandsDir("compile-commands-dir", llvm::cl::desc("Specify a path to look for compile_commands.json. If path " "is invalid, clangd will look in the current directory and " "parent paths of each source file."))