clang-tools  8.0.0
GlobalCompilationDatabase.cpp
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1 //===--- GlobalCompilationDatabase.cpp ---------------------------*- 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 
11 #include "Logger.h"
12 #include "clang/Frontend/CompilerInvocation.h"
13 #include "clang/Tooling/ArgumentsAdjusters.h"
14 #include "clang/Tooling/CompilationDatabase.h"
15 #include "llvm/ADT/Optional.h"
16 #include "llvm/Support/FileSystem.h"
17 #include "llvm/Support/Path.h"
18 
19 namespace clang {
20 namespace clangd {
21 namespace {
22 
23 void adjustArguments(tooling::CompileCommand &Cmd,
24  llvm::StringRef ResourceDir) {
25  // Strip plugin related command line arguments. Clangd does
26  // not support plugins currently. Therefore it breaks if
27  // compiler tries to load plugins.
28  Cmd.CommandLine =
29  tooling::getStripPluginsAdjuster()(Cmd.CommandLine, Cmd.Filename);
30  // Inject the resource dir.
31  // FIXME: Don't overwrite it if it's already there.
32  if (!ResourceDir.empty())
33  Cmd.CommandLine.push_back(("-resource-dir=" + ResourceDir).str());
34 }
35 
36 std::string getStandardResourceDir() {
37  static int Dummy; // Just an address in this process.
38  return CompilerInvocation::GetResourcesPath("clangd", (void *)&Dummy);
39 }
40 
41 } // namespace
42 
43 static std::string getFallbackClangPath() {
44  static int Dummy;
45  std::string ClangdExecutable =
46  llvm::sys::fs::getMainExecutable("clangd", (void *)&Dummy);
47  SmallString<128> ClangPath;
48  ClangPath = llvm::sys::path::parent_path(ClangdExecutable);
49  llvm::sys::path::append(ClangPath, "clang");
50  return ClangPath.str();
51 }
52 
53 tooling::CompileCommand
55  std::vector<std::string> Argv = {getFallbackClangPath()};
56  // Clang treats .h files as C by default, resulting in unhelpful diagnostics.
57  // Parsing as Objective C++ is friendly to more cases.
58  if (llvm::sys::path::extension(File) == ".h")
59  Argv.push_back("-xobjective-c++-header");
60  Argv.push_back(File);
61  return tooling::CompileCommand(llvm::sys::path::parent_path(File),
62  llvm::sys::path::filename(File),
63  std::move(Argv),
64  /*Output=*/"");
65 }
66 
69  llvm::Optional<Path> CompileCommandsDir)
70  : CompileCommandsDir(std::move(CompileCommandsDir)) {}
71 
74 
75 llvm::Optional<tooling::CompileCommand>
77  PathRef File, ProjectInfo *Project) const {
78  if (auto CDB = getCDBForFile(File, Project)) {
79  auto Candidates = CDB->getCompileCommands(File);
80  if (!Candidates.empty()) {
81  return std::move(Candidates.front());
82  }
83  } else {
84  log("Failed to find compilation database for {0}", File);
85  }
86  return None;
87 }
88 
89 std::pair<tooling::CompilationDatabase *, /*Cached*/ bool>
90 DirectoryBasedGlobalCompilationDatabase::getCDBInDirLocked(PathRef Dir) const {
91  // FIXME(ibiryukov): Invalidate cached compilation databases on changes
92  auto CachedIt = CompilationDatabases.find(Dir);
93  if (CachedIt != CompilationDatabases.end())
94  return {CachedIt->second.get(), true};
95  std::string Error = "";
96  auto CDB = tooling::CompilationDatabase::loadFromDirectory(Dir, Error);
97  auto Result = CDB.get();
98  CompilationDatabases.insert(std::make_pair(Dir, std::move(CDB)));
99  return {Result, false};
100 }
101 
102 tooling::CompilationDatabase *
103 DirectoryBasedGlobalCompilationDatabase::getCDBForFile(
104  PathRef File, ProjectInfo *Project) const {
105  namespace path = llvm::sys::path;
106  assert((path::is_absolute(File, path::Style::posix) ||
107  path::is_absolute(File, path::Style::windows)) &&
108  "path must be absolute");
109 
110  tooling::CompilationDatabase *CDB = nullptr;
111  bool Cached = false;
112  std::lock_guard<std::mutex> Lock(Mutex);
113  if (CompileCommandsDir) {
114  std::tie(CDB, Cached) = getCDBInDirLocked(*CompileCommandsDir);
115  if (Project && CDB)
116  Project->SourceRoot = *CompileCommandsDir;
117  } else {
118  for (auto Path = path::parent_path(File); !CDB && !Path.empty();
119  Path = path::parent_path(Path)) {
120  std::tie(CDB, Cached) = getCDBInDirLocked(Path);
121  if (Project && CDB)
122  Project->SourceRoot = Path;
123  }
124  }
125  // FIXME: getAllFiles() may return relative paths, we need absolute paths.
126  // Hopefully the fix is to change JSONCompilationDatabase and the interface.
127  if (CDB && !Cached)
128  OnCommandChanged.broadcast(CDB->getAllFiles());
129  return CDB;
130 }
131 
133  std::vector<std::string> FallbackFlags,
134  llvm::Optional<std::string> ResourceDir)
135  : Base(Base), ResourceDir(ResourceDir ? std::move(*ResourceDir)
136  : getStandardResourceDir()),
137  FallbackFlags(std::move(FallbackFlags)) {
138  if (Base)
139  BaseChanged = Base->watch([this](const std::vector<std::string> Changes) {
140  OnCommandChanged.broadcast(Changes);
141  });
142 }
143 
144 llvm::Optional<tooling::CompileCommand>
146  llvm::Optional<tooling::CompileCommand> Cmd;
147  {
148  std::lock_guard<std::mutex> Lock(Mutex);
149  auto It = Commands.find(File);
150  if (It != Commands.end()) {
151  if (Project)
152  Project->SourceRoot = "";
153  Cmd = It->second;
154  }
155  }
156  if (!Cmd && Base)
157  Cmd = Base->getCompileCommand(File, Project);
158  if (!Cmd)
159  return llvm::None;
160  adjustArguments(*Cmd, ResourceDir);
161  return Cmd;
162 }
163 
164 tooling::CompileCommand OverlayCDB::getFallbackCommand(PathRef File) const {
165  auto Cmd = Base ? Base->getFallbackCommand(File)
167  std::lock_guard<std::mutex> Lock(Mutex);
168  Cmd.CommandLine.insert(Cmd.CommandLine.end(), FallbackFlags.begin(),
169  FallbackFlags.end());
170  return Cmd;
171 }
172 
174  PathRef File, llvm::Optional<tooling::CompileCommand> Cmd) {
175  {
176  std::unique_lock<std::mutex> Lock(Mutex);
177  if (Cmd)
178  Commands[File] = std::move(*Cmd);
179  else
180  Commands.erase(File);
181  }
182  OnCommandChanged.broadcast({File});
183 }
184 
185 } // namespace clangd
186 } // namespace clang
llvm::Optional< tooling::CompileCommand > getCompileCommand(PathRef File, ProjectInfo *=nullptr) const override
Scans File&#39;s parents looking for compilation databases.
static std::string getFallbackClangPath()
virtual llvm::Optional< tooling::CompileCommand > getCompileCommand(PathRef File, ProjectInfo *=nullptr) const =0
If there are any known-good commands for building this file, returns one.
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
Documents should not be synced at all.
Provides compilation arguments used for parsing C and C++ files.
llvm::Optional< tooling::CompileCommand > getCompileCommand(PathRef File, ProjectInfo *=nullptr) const override
If there are any known-good commands for building this file, returns one.
void broadcast(const T &V)
Definition: Function.h:140
void log(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:63
std::string Path
A typedef to represent a file path.
Definition: Path.h:21
llvm::Optional< llvm::Expected< tooling::AtomicChanges > > Result
DirectoryBasedGlobalCompilationDatabase(llvm::Optional< Path > CompileCommandsDir)
tooling::CompileCommand getFallbackCommand(PathRef File) const override
Makes a guess at how to build a file.
void setCompileCommand(PathRef File, llvm::Optional< tooling::CompileCommand > CompilationCommand)
Sets or clears the compilation command for a particular file.
static llvm::cl::opt< Path > ResourceDir("resource-dir", llvm::cl::desc("Directory for system clang headers"), llvm::cl::init(""), llvm::cl::Hidden)
OverlayCDB(const GlobalCompilationDatabase *Base, std::vector< std::string > FallbackFlags={}, llvm::Optional< std::string > ResourceDir=llvm::None)
CommandChanged::Subscription watch(CommandChanged::Listener L) const
The callback is notified when files may have new compile commands.
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
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."))
virtual tooling::CompileCommand getFallbackCommand(PathRef File) const
Makes a guess at how to build a file.