clang  6.0.0svn
CompilationDatabase.cpp
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1 //===--- CompilationDatabase.cpp - ----------------------------------------===//
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 // This file contains implementations of the CompilationDatabase base class
11 // and the FixedCompilationDatabase.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "clang/Basic/Diagnostic.h"
18 #include "clang/Driver/Action.h"
20 #include "clang/Driver/Driver.h"
22 #include "clang/Driver/Job.h"
25 #include "clang/Tooling/Tooling.h"
26 #include "llvm/ADT/SmallString.h"
27 #include "llvm/Option/Arg.h"
28 #include "llvm/Support/Host.h"
29 #include "llvm/Support/Path.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include <sstream>
32 #include <system_error>
33 using namespace clang;
34 using namespace tooling;
35 
36 LLVM_INSTANTIATE_REGISTRY(CompilationDatabasePluginRegistry)
37 
39 
40 std::unique_ptr<CompilationDatabase>
41 CompilationDatabase::loadFromDirectory(StringRef BuildDirectory,
42  std::string &ErrorMessage) {
43  llvm::raw_string_ostream ErrorStream(ErrorMessage);
44  for (CompilationDatabasePluginRegistry::iterator
45  It = CompilationDatabasePluginRegistry::begin(),
46  Ie = CompilationDatabasePluginRegistry::end();
47  It != Ie; ++It) {
48  std::string DatabaseErrorMessage;
49  std::unique_ptr<CompilationDatabasePlugin> Plugin(It->instantiate());
50  if (std::unique_ptr<CompilationDatabase> DB =
51  Plugin->loadFromDirectory(BuildDirectory, DatabaseErrorMessage))
52  return DB;
53  ErrorStream << It->getName() << ": " << DatabaseErrorMessage << "\n";
54  }
55  return nullptr;
56 }
57 
58 static std::unique_ptr<CompilationDatabase>
60  std::string &ErrorMessage) {
61  std::stringstream ErrorStream;
62  bool HasErrorMessage = false;
63  while (!Directory.empty()) {
64  std::string LoadErrorMessage;
65 
66  if (std::unique_ptr<CompilationDatabase> DB =
67  CompilationDatabase::loadFromDirectory(Directory, LoadErrorMessage))
68  return DB;
69 
70  if (!HasErrorMessage) {
71  ErrorStream << "No compilation database found in " << Directory.str()
72  << " or any parent directory\n" << LoadErrorMessage;
73  HasErrorMessage = true;
74  }
75 
76  Directory = llvm::sys::path::parent_path(Directory);
77  }
78  ErrorMessage = ErrorStream.str();
79  return nullptr;
80 }
81 
82 std::unique_ptr<CompilationDatabase>
84  std::string &ErrorMessage) {
85  SmallString<1024> AbsolutePath(getAbsolutePath(SourceFile));
86  StringRef Directory = llvm::sys::path::parent_path(AbsolutePath);
87 
88  std::unique_ptr<CompilationDatabase> DB =
89  findCompilationDatabaseFromDirectory(Directory, ErrorMessage);
90 
91  if (!DB)
92  ErrorMessage = ("Could not auto-detect compilation database for file \"" +
93  SourceFile + "\"\n" + ErrorMessage).str();
94  return DB;
95 }
96 
97 std::unique_ptr<CompilationDatabase>
99  std::string &ErrorMessage) {
100  SmallString<1024> AbsolutePath(getAbsolutePath(SourceDir));
101 
102  std::unique_ptr<CompilationDatabase> DB =
103  findCompilationDatabaseFromDirectory(AbsolutePath, ErrorMessage);
104 
105  if (!DB)
106  ErrorMessage = ("Could not auto-detect compilation database from directory \"" +
107  SourceDir + "\"\n" + ErrorMessage).str();
108  return DB;
109 }
110 
112 
113 namespace {
114 // Helper for recursively searching through a chain of actions and collecting
115 // all inputs, direct and indirect, of compile jobs.
116 struct CompileJobAnalyzer {
117  void run(const driver::Action *A) {
118  runImpl(A, false);
119  }
120 
122 
123 private:
124 
125  void runImpl(const driver::Action *A, bool Collect) {
126  bool CollectChildren = Collect;
127  switch (A->getKind()) {
129  CollectChildren = true;
130  break;
131 
133  if (Collect) {
134  const driver::InputAction *IA = cast<driver::InputAction>(A);
135  Inputs.push_back(IA->getInputArg().getSpelling());
136  }
137  } break;
138 
139  default:
140  // Don't care about others
141  ;
142  }
143 
144  for (const driver::Action *AI : A->inputs())
145  runImpl(AI, CollectChildren);
146  }
147 };
148 
149 // Special DiagnosticConsumer that looks for warn_drv_input_file_unused
150 // diagnostics from the driver and collects the option strings for those unused
151 // options.
152 class UnusedInputDiagConsumer : public DiagnosticConsumer {
153 public:
154  UnusedInputDiagConsumer(DiagnosticConsumer &Other) : Other(Other) {}
155 
156  void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
157  const Diagnostic &Info) override {
158  if (Info.getID() == clang::diag::warn_drv_input_file_unused) {
159  // Arg 1 for this diagnostic is the option that didn't get used.
160  UnusedInputs.push_back(Info.getArgStdStr(0));
161  } else if (DiagLevel >= DiagnosticsEngine::Error) {
162  // If driver failed to create compilation object, show the diagnostics
163  // to user.
164  Other.HandleDiagnostic(DiagLevel, Info);
165  }
166  }
167 
168  DiagnosticConsumer &Other;
169  SmallVector<std::string, 2> UnusedInputs;
170 };
171 
172 // Unary functor for asking "Given a StringRef S1, does there exist a string
173 // S2 in Arr where S1 == S2?"
174 struct MatchesAny {
175  MatchesAny(ArrayRef<std::string> Arr) : Arr(Arr) {}
176  bool operator() (StringRef S) {
177  for (const std::string *I = Arr.begin(), *E = Arr.end(); I != E; ++I)
178  if (*I == S)
179  return true;
180  return false;
181  }
182 private:
184 };
185 } // namespace
186 
187 /// \brief Strips any positional args and possible argv[0] from a command-line
188 /// provided by the user to construct a FixedCompilationDatabase.
189 ///
190 /// FixedCompilationDatabase requires a command line to be in this format as it
191 /// constructs the command line for each file by appending the name of the file
192 /// to be compiled. FixedCompilationDatabase also adds its own argv[0] to the
193 /// start of the command line although its value is not important as it's just
194 /// ignored by the Driver invoked by the ClangTool using the
195 /// FixedCompilationDatabase.
196 ///
197 /// FIXME: This functionality should probably be made available by
198 /// clang::driver::Driver although what the interface should look like is not
199 /// clear.
200 ///
201 /// \param[in] Args Args as provided by the user.
202 /// \return Resulting stripped command line.
203 /// \li true if successful.
204 /// \li false if \c Args cannot be used for compilation jobs (e.g.
205 /// contains an option like -E or -version).
206 static bool stripPositionalArgs(std::vector<const char *> Args,
207  std::vector<std::string> &Result,
208  std::string &ErrorMsg) {
210  llvm::raw_string_ostream Output(ErrorMsg);
211  TextDiagnosticPrinter DiagnosticPrinter(Output, &*DiagOpts);
212  UnusedInputDiagConsumer DiagClient(DiagnosticPrinter);
213  DiagnosticsEngine Diagnostics(
215  &*DiagOpts, &DiagClient, false);
216 
217  // The clang executable path isn't required since the jobs the driver builds
218  // will not be executed.
219  std::unique_ptr<driver::Driver> NewDriver(new driver::Driver(
220  /* ClangExecutable= */ "", llvm::sys::getDefaultTargetTriple(),
221  Diagnostics));
222  NewDriver->setCheckInputsExist(false);
223 
224  // This becomes the new argv[0]. The value is actually not important as it
225  // isn't used for invoking Tools.
226  Args.insert(Args.begin(), "clang-tool");
227 
228  // By adding -c, we force the driver to treat compilation as the last phase.
229  // It will then issue warnings via Diagnostics about un-used options that
230  // would have been used for linking. If the user provided a compiler name as
231  // the original argv[0], this will be treated as a linker input thanks to
232  // insertng a new argv[0] above. All un-used options get collected by
233  // UnusedInputdiagConsumer and get stripped out later.
234  Args.push_back("-c");
235 
236  // Put a dummy C++ file on to ensure there's at least one compile job for the
237  // driver to construct. If the user specified some other argument that
238  // prevents compilation, e.g. -E or something like -version, we may still end
239  // up with no jobs but then this is the user's fault.
240  Args.push_back("placeholder.cpp");
241 
242  // Remove -no-integrated-as; it's not used for syntax checking,
243  // and it confuses targets which don't support this option.
244  Args.erase(std::remove_if(Args.begin(), Args.end(),
245  MatchesAny(std::string("-no-integrated-as"))),
246  Args.end());
247 
248  const std::unique_ptr<driver::Compilation> Compilation(
249  NewDriver->BuildCompilation(Args));
250  if (!Compilation)
251  return false;
252 
253  const driver::JobList &Jobs = Compilation->getJobs();
254 
255  CompileJobAnalyzer CompileAnalyzer;
256 
257  for (const auto &Cmd : Jobs) {
258  // Collect only for Assemble and Compile jobs. If we do all jobs we get
259  // duplicates since Link jobs point to Assemble jobs as inputs.
260  if (Cmd.getSource().getKind() == driver::Action::AssembleJobClass ||
261  Cmd.getSource().getKind() == driver::Action::CompileJobClass) {
262  CompileAnalyzer.run(&Cmd.getSource());
263  }
264  }
265 
266  if (CompileAnalyzer.Inputs.empty()) {
267  ErrorMsg = "warning: no compile jobs found\n";
268  return false;
269  }
270 
271  // Remove all compilation input files from the command line. This is
272  // necessary so that getCompileCommands() can construct a command line for
273  // each file.
274  std::vector<const char *>::iterator End = std::remove_if(
275  Args.begin(), Args.end(), MatchesAny(CompileAnalyzer.Inputs));
276 
277  // Remove all inputs deemed unused for compilation.
278  End = std::remove_if(Args.begin(), End, MatchesAny(DiagClient.UnusedInputs));
279 
280  // Remove the -c add above as well. It will be at the end right now.
281  assert(strcmp(*(End - 1), "-c") == 0);
282  --End;
283 
284  Result = std::vector<std::string>(Args.begin() + 1, End);
285  return true;
286 }
287 
288 std::unique_ptr<FixedCompilationDatabase>
290  const char *const *Argv,
291  std::string &ErrorMsg,
292  Twine Directory) {
293  ErrorMsg.clear();
294  if (Argc == 0)
295  return nullptr;
296  const char *const *DoubleDash = std::find(Argv, Argv + Argc, StringRef("--"));
297  if (DoubleDash == Argv + Argc)
298  return nullptr;
299  std::vector<const char *> CommandLine(DoubleDash + 1, Argv + Argc);
300  Argc = DoubleDash - Argv;
301 
302  std::vector<std::string> StrippedArgs;
303  if (!stripPositionalArgs(CommandLine, StrippedArgs, ErrorMsg))
304  return nullptr;
305  return std::unique_ptr<FixedCompilationDatabase>(
306  new FixedCompilationDatabase(Directory, StrippedArgs));
307 }
308 
310 FixedCompilationDatabase(Twine Directory, ArrayRef<std::string> CommandLine) {
311  std::vector<std::string> ToolCommandLine(1, "clang-tool");
312  ToolCommandLine.insert(ToolCommandLine.end(),
313  CommandLine.begin(), CommandLine.end());
314  CompileCommands.emplace_back(Directory, StringRef(),
315  std::move(ToolCommandLine),
316  StringRef());
317 }
318 
319 std::vector<CompileCommand>
321  std::vector<CompileCommand> Result(CompileCommands);
322  Result[0].CommandLine.push_back(FilePath);
323  Result[0].Filename = FilePath;
324  return Result;
325 }
326 
327 std::vector<std::string>
329  return std::vector<std::string>();
330 }
331 
332 std::vector<CompileCommand>
334  return std::vector<CompileCommand>();
335 }
336 
337 namespace clang {
338 namespace tooling {
339 
340 // This anchor is used to force the linker to link in the generated object file
341 // and thus register the JSONCompilationDatabasePlugin.
342 extern volatile int JSONAnchorSource;
343 static int LLVM_ATTRIBUTE_UNUSED JSONAnchorDest = JSONAnchorSource;
344 
345 } // end namespace tooling
346 } // end namespace clang
static std::unique_ptr< CompilationDatabase > autoDetectFromDirectory(StringRef SourceDir, std::string &ErrorMessage)
Tries to detect a compilation database location and load it.
static std::unique_ptr< CompilationDatabase > findCompilationDatabaseFromDirectory(StringRef Directory, std::string &ErrorMessage)
input_range inputs()
Definition: Action.h:141
std::vector< CompileCommand > getCompileCommands(StringRef FilePath) const override
Returns the given compile command.
Abstract interface, implemented by clients of the front-end, which formats and prints fully processed...
Definition: Diagnostic.h:1395
llvm::Registry< CompilationDatabasePlugin > CompilationDatabasePluginRegistry
const llvm::opt::Arg & getInputArg() const
Definition: Action.h:205
Represents the diagnostic with the level of severity and possible fixes to be applied.
Definition: Diagnostic.h:50
Action - Represent an abstract compilation step to perform.
Definition: Action.h:45
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:147
Defines the Diagnostic-related interfaces.
Driver - Encapsulate logic for constructing compilation processes from a set of gcc-driver-like comma...
Definition: Driver.h:65
ActionClass getKind() const
Definition: Action.h:131
SourceLocation End
std::string getAbsolutePath(StringRef File)
Returns the absolute path of File, by prepending it with the current directory if File is not absolut...
Definition: Tooling.cpp:162
JobList - A sequence of jobs to perform.
Definition: Job.h:166
static bool stripPositionalArgs(std::vector< const char *> Args, std::vector< std::string > &Result, std::string &ErrorMsg)
Strips any positional args and possible argv[0] from a command-line provided by the user to construct...
Interface for compilation databases.
static std::unique_ptr< FixedCompilationDatabase > loadFromCommandLine(int &Argc, const char *const *Argv, std::string &ErrorMsg, Twine Directory=".")
Creates a FixedCompilationDatabase from the arguments after "--".
Options for controlling the compiler diagnostics engine.
static std::unique_ptr< CompilationDatabase > autoDetectFromSource(StringRef SourceFile, std::string &ErrorMessage)
Tries to detect a compilation database location and load it.
virtual void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel, const Diagnostic &Info)
Handle this diagnostic, reporting it to the user or capturing it to a log as needed.
Definition: Diagnostic.cpp:435
std::vector< CompileCommand > getAllCompileCommands() const override
Returns all compile commands for all the files in the compilation database.
Dataflow Directional Tag Classes.
Used for handling and querying diagnostic IDs.
FixedCompilationDatabase(Twine Directory, ArrayRef< std::string > CommandLine)
Constructs a compilation data base from a specified directory and command line.
Level
The level of the diagnostic, after it has been through mapping.
Definition: Diagnostic.h:150
std::vector< std::string > getAllFiles() const override
Returns the list of all files available in the compilation database.
static std::unique_ptr< CompilationDatabase > loadFromDirectory(StringRef BuildDirectory, std::string &ErrorMessage)
Loads a compilation database from a build directory.
static int LLVM_ATTRIBUTE_UNUSED JSONAnchorDest
A compilation database that returns a single compile command line.
const list_type & getJobs() const
Definition: Job.h:186