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
15 #include "clang/Tooling/CompilationDatabase.h"
16 #include "clang/Basic/Diagnostic.h"
17 #include "clang/Basic/DiagnosticOptions.h"
18 #include "clang/Driver/Action.h"
19 #include "clang/Driver/Compilation.h"
20 #include "clang/Driver/Driver.h"
21 #include "clang/Driver/DriverDiagnostic.h"
22 #include "clang/Driver/Job.h"
23 #include "clang/Frontend/TextDiagnosticPrinter.h"
24 #include "clang/Tooling/CompilationDatabasePluginRegistry.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 <sstream>
31 #include <system_error>
32 using namespace clang;
33 using namespace tooling;
34
~CompilationDatabase()35 CompilationDatabase::~CompilationDatabase() {}
36
37 std::unique_ptr<CompilationDatabase>
loadFromDirectory(StringRef BuildDirectory,std::string & ErrorMessage)38 CompilationDatabase::loadFromDirectory(StringRef BuildDirectory,
39 std::string &ErrorMessage) {
40 std::stringstream ErrorStream;
41 for (CompilationDatabasePluginRegistry::iterator
42 It = CompilationDatabasePluginRegistry::begin(),
43 Ie = CompilationDatabasePluginRegistry::end();
44 It != Ie; ++It) {
45 std::string DatabaseErrorMessage;
46 std::unique_ptr<CompilationDatabasePlugin> Plugin(It->instantiate());
47 if (std::unique_ptr<CompilationDatabase> DB =
48 Plugin->loadFromDirectory(BuildDirectory, DatabaseErrorMessage))
49 return DB;
50 ErrorStream << It->getName() << ": " << DatabaseErrorMessage << "\n";
51 }
52 ErrorMessage = ErrorStream.str();
53 return nullptr;
54 }
55
56 static std::unique_ptr<CompilationDatabase>
findCompilationDatabaseFromDirectory(StringRef Directory,std::string & ErrorMessage)57 findCompilationDatabaseFromDirectory(StringRef Directory,
58 std::string &ErrorMessage) {
59 std::stringstream ErrorStream;
60 bool HasErrorMessage = false;
61 while (!Directory.empty()) {
62 std::string LoadErrorMessage;
63
64 if (std::unique_ptr<CompilationDatabase> DB =
65 CompilationDatabase::loadFromDirectory(Directory, LoadErrorMessage))
66 return DB;
67
68 if (!HasErrorMessage) {
69 ErrorStream << "No compilation database found in " << Directory.str()
70 << " or any parent directory\n" << LoadErrorMessage;
71 HasErrorMessage = true;
72 }
73
74 Directory = llvm::sys::path::parent_path(Directory);
75 }
76 ErrorMessage = ErrorStream.str();
77 return nullptr;
78 }
79
80 std::unique_ptr<CompilationDatabase>
autoDetectFromSource(StringRef SourceFile,std::string & ErrorMessage)81 CompilationDatabase::autoDetectFromSource(StringRef SourceFile,
82 std::string &ErrorMessage) {
83 SmallString<1024> AbsolutePath(getAbsolutePath(SourceFile));
84 StringRef Directory = llvm::sys::path::parent_path(AbsolutePath);
85
86 std::unique_ptr<CompilationDatabase> DB =
87 findCompilationDatabaseFromDirectory(Directory, ErrorMessage);
88
89 if (!DB)
90 ErrorMessage = ("Could not auto-detect compilation database for file \"" +
91 SourceFile + "\"\n" + ErrorMessage).str();
92 return DB;
93 }
94
95 std::unique_ptr<CompilationDatabase>
autoDetectFromDirectory(StringRef SourceDir,std::string & ErrorMessage)96 CompilationDatabase::autoDetectFromDirectory(StringRef SourceDir,
97 std::string &ErrorMessage) {
98 SmallString<1024> AbsolutePath(getAbsolutePath(SourceDir));
99
100 std::unique_ptr<CompilationDatabase> DB =
101 findCompilationDatabaseFromDirectory(AbsolutePath, ErrorMessage);
102
103 if (!DB)
104 ErrorMessage = ("Could not auto-detect compilation database from directory \"" +
105 SourceDir + "\"\n" + ErrorMessage).str();
106 return DB;
107 }
108
~CompilationDatabasePlugin()109 CompilationDatabasePlugin::~CompilationDatabasePlugin() {}
110
111 namespace {
112 // Helper for recursively searching through a chain of actions and collecting
113 // all inputs, direct and indirect, of compile jobs.
114 struct CompileJobAnalyzer {
run__anon970dbca40111::CompileJobAnalyzer115 void run(const driver::Action *A) {
116 runImpl(A, false);
117 }
118
119 SmallVector<std::string, 2> Inputs;
120
121 private:
122
runImpl__anon970dbca40111::CompileJobAnalyzer123 void runImpl(const driver::Action *A, bool Collect) {
124 bool CollectChildren = Collect;
125 switch (A->getKind()) {
126 case driver::Action::CompileJobClass:
127 CollectChildren = true;
128 break;
129
130 case driver::Action::InputClass: {
131 if (Collect) {
132 const driver::InputAction *IA = cast<driver::InputAction>(A);
133 Inputs.push_back(IA->getInputArg().getSpelling());
134 }
135 } break;
136
137 default:
138 // Don't care about others
139 ;
140 }
141
142 for (const driver::Action *AI : A->inputs())
143 runImpl(AI, CollectChildren);
144 }
145 };
146
147 // Special DiagnosticConsumer that looks for warn_drv_input_file_unused
148 // diagnostics from the driver and collects the option strings for those unused
149 // options.
150 class UnusedInputDiagConsumer : public DiagnosticConsumer {
151 public:
UnusedInputDiagConsumer()152 UnusedInputDiagConsumer() : Other(nullptr) {}
153
154 // Useful for debugging, chain diagnostics to another consumer after
155 // recording for our own purposes.
UnusedInputDiagConsumer(DiagnosticConsumer * Other)156 UnusedInputDiagConsumer(DiagnosticConsumer *Other) : Other(Other) {}
157
HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,const Diagnostic & Info)158 void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
159 const Diagnostic &Info) override {
160 if (Info.getID() == clang::diag::warn_drv_input_file_unused) {
161 // Arg 1 for this diagnostic is the option that didn't get used.
162 UnusedInputs.push_back(Info.getArgStdStr(0));
163 }
164 if (Other)
165 Other->HandleDiagnostic(DiagLevel, Info);
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 {
MatchesAny__anon970dbca40111::MatchesAny175 MatchesAny(ArrayRef<std::string> Arr) : Arr(Arr) {}
operator ()__anon970dbca40111::MatchesAny176 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:
183 ArrayRef<std::string> Arr;
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).
stripPositionalArgs(std::vector<const char * > Args,std::vector<std::string> & Result)206 static bool stripPositionalArgs(std::vector<const char *> Args,
207 std::vector<std::string> &Result) {
208 IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
209 UnusedInputDiagConsumer DiagClient;
210 DiagnosticsEngine Diagnostics(
211 IntrusiveRefCntPtr<clang::DiagnosticIDs>(new DiagnosticIDs()),
212 &*DiagOpts, &DiagClient, false);
213
214 // The clang executable path isn't required since the jobs the driver builds
215 // will not be executed.
216 std::unique_ptr<driver::Driver> NewDriver(new driver::Driver(
217 /* ClangExecutable= */ "", llvm::sys::getDefaultTargetTriple(),
218 Diagnostics));
219 NewDriver->setCheckInputsExist(false);
220
221 // This becomes the new argv[0]. The value is actually not important as it
222 // isn't used for invoking Tools.
223 Args.insert(Args.begin(), "clang-tool");
224
225 // By adding -c, we force the driver to treat compilation as the last phase.
226 // It will then issue warnings via Diagnostics about un-used options that
227 // would have been used for linking. If the user provided a compiler name as
228 // the original argv[0], this will be treated as a linker input thanks to
229 // insertng a new argv[0] above. All un-used options get collected by
230 // UnusedInputdiagConsumer and get stripped out later.
231 Args.push_back("-c");
232
233 // Put a dummy C++ file on to ensure there's at least one compile job for the
234 // driver to construct. If the user specified some other argument that
235 // prevents compilation, e.g. -E or something like -version, we may still end
236 // up with no jobs but then this is the user's fault.
237 Args.push_back("placeholder.cpp");
238
239 // Remove -no-integrated-as; it's not used for syntax checking,
240 // and it confuses targets which don't support this option.
241 Args.erase(std::remove_if(Args.begin(), Args.end(),
242 MatchesAny(std::string("-no-integrated-as"))),
243 Args.end());
244
245 const std::unique_ptr<driver::Compilation> Compilation(
246 NewDriver->BuildCompilation(Args));
247
248 const driver::JobList &Jobs = Compilation->getJobs();
249
250 CompileJobAnalyzer CompileAnalyzer;
251
252 for (const auto &Cmd : Jobs) {
253 // Collect only for Assemble jobs. If we do all jobs we get duplicates
254 // since Link jobs point to Assemble jobs as inputs.
255 if (Cmd.getSource().getKind() == driver::Action::AssembleJobClass)
256 CompileAnalyzer.run(&Cmd.getSource());
257 }
258
259 if (CompileAnalyzer.Inputs.empty()) {
260 // No compile jobs found.
261 // FIXME: Emit a warning of some kind?
262 return false;
263 }
264
265 // Remove all compilation input files from the command line. This is
266 // necessary so that getCompileCommands() can construct a command line for
267 // each file.
268 std::vector<const char *>::iterator End = std::remove_if(
269 Args.begin(), Args.end(), MatchesAny(CompileAnalyzer.Inputs));
270
271 // Remove all inputs deemed unused for compilation.
272 End = std::remove_if(Args.begin(), End, MatchesAny(DiagClient.UnusedInputs));
273
274 // Remove the -c add above as well. It will be at the end right now.
275 assert(strcmp(*(End - 1), "-c") == 0);
276 --End;
277
278 Result = std::vector<std::string>(Args.begin() + 1, End);
279 return true;
280 }
281
loadFromCommandLine(int & Argc,const char * const * Argv,Twine Directory)282 FixedCompilationDatabase *FixedCompilationDatabase::loadFromCommandLine(
283 int &Argc, const char *const *Argv, Twine Directory) {
284 const char *const *DoubleDash = std::find(Argv, Argv + Argc, StringRef("--"));
285 if (DoubleDash == Argv + Argc)
286 return nullptr;
287 std::vector<const char *> CommandLine(DoubleDash + 1, Argv + Argc);
288 Argc = DoubleDash - Argv;
289
290 std::vector<std::string> StrippedArgs;
291 if (!stripPositionalArgs(CommandLine, StrippedArgs))
292 return nullptr;
293 return new FixedCompilationDatabase(Directory, StrippedArgs);
294 }
295
296 FixedCompilationDatabase::
FixedCompilationDatabase(Twine Directory,ArrayRef<std::string> CommandLine)297 FixedCompilationDatabase(Twine Directory, ArrayRef<std::string> CommandLine) {
298 std::vector<std::string> ToolCommandLine(1, "clang-tool");
299 ToolCommandLine.insert(ToolCommandLine.end(),
300 CommandLine.begin(), CommandLine.end());
301 CompileCommands.emplace_back(Directory, StringRef(),
302 std::move(ToolCommandLine));
303 }
304
305 std::vector<CompileCommand>
getCompileCommands(StringRef FilePath) const306 FixedCompilationDatabase::getCompileCommands(StringRef FilePath) const {
307 std::vector<CompileCommand> Result(CompileCommands);
308 Result[0].CommandLine.push_back(FilePath);
309 Result[0].Filename = FilePath;
310 return Result;
311 }
312
313 std::vector<std::string>
getAllFiles() const314 FixedCompilationDatabase::getAllFiles() const {
315 return std::vector<std::string>();
316 }
317
318 std::vector<CompileCommand>
getAllCompileCommands() const319 FixedCompilationDatabase::getAllCompileCommands() const {
320 return std::vector<CompileCommand>();
321 }
322
323 namespace clang {
324 namespace tooling {
325
326 // This anchor is used to force the linker to link in the generated object file
327 // and thus register the JSONCompilationDatabasePlugin.
328 extern volatile int JSONAnchorSource;
329 static int LLVM_ATTRIBUTE_UNUSED JSONAnchorDest = JSONAnchorSource;
330
331 } // end namespace tooling
332 } // end namespace clang
333