CompilerInstance.cpp revision d2536a604f59a3cca491f175bf1e49eeca49163b 
1//===--- CompilerInstance.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#include "clang/Frontend/CompilerInstance.h"
11#include "clang/Sema/Sema.h"
12#include "clang/AST/ASTConsumer.h"
13#include "clang/AST/ASTContext.h"
14#include "clang/Basic/Diagnostic.h"
15#include "clang/Basic/FileManager.h"
16#include "clang/Basic/SourceManager.h"
17#include "clang/Basic/TargetInfo.h"
18#include "clang/Basic/Version.h"
19#include "clang/Lex/HeaderSearch.h"
20#include "clang/Lex/Preprocessor.h"
21#include "clang/Lex/PTHManager.h"
22#include "clang/Frontend/ChainedDiagnosticConsumer.h"
23#include "clang/Frontend/FrontendAction.h"
24#include "clang/Frontend/FrontendActions.h"
25#include "clang/Frontend/FrontendDiagnostic.h"
26#include "clang/Frontend/LogDiagnosticPrinter.h"
27#include "clang/Frontend/SerializedDiagnosticPrinter.h"
28#include "clang/Frontend/TextDiagnosticPrinter.h"
29#include "clang/Frontend/VerifyDiagnosticConsumer.h"
30#include "clang/Frontend/Utils.h"
31#include "clang/Serialization/ASTReader.h"
32#include "clang/Sema/CodeCompleteConsumer.h"
33#include "llvm/Support/FileSystem.h"
34#include "llvm/Support/MemoryBuffer.h"
35#include "llvm/Support/raw_ostream.h"
36#include "llvm/ADT/Statistic.h"
37#include "llvm/Support/Timer.h"
38#include "llvm/Support/Host.h"
39#include "llvm/Support/Path.h"
40#include "llvm/Support/Program.h"
41#include "llvm/Support/Signals.h"
42#include "llvm/Support/system_error.h"
43#include "llvm/Support/CrashRecoveryContext.h"
44#include "llvm/Config/config.h"
45
46// Support for FileLockManager
47#include <fstream>
48#include <sys/types.h>
49#include <sys/stat.h>
50
51#if LLVM_ON_WIN32
52#include <windows.h>
53#endif
54#if LLVM_ON_UNIX
55#include <unistd.h>
56#endif
57
58using namespace clang;
59
60CompilerInstance::CompilerInstance()
61  : Invocation(new CompilerInvocation()), ModuleManager(0) {
62}
63
64CompilerInstance::~CompilerInstance() {
65}
66
67void CompilerInstance::setInvocation(CompilerInvocation *Value) {
68  Invocation = Value;
69}
70
71void CompilerInstance::setDiagnostics(DiagnosticsEngine *Value) {
72  Diagnostics = Value;
73}
74
75void CompilerInstance::setTarget(TargetInfo *Value) {
76  Target = Value;
77}
78
79void CompilerInstance::setFileManager(FileManager *Value) {
80  FileMgr = Value;
81}
82
83void CompilerInstance::setSourceManager(SourceManager *Value) {
84  SourceMgr = Value;
85}
86
87void CompilerInstance::setPreprocessor(Preprocessor *Value) { PP = Value; }
88
89void CompilerInstance::setASTContext(ASTContext *Value) { Context = Value; }
90
91void CompilerInstance::setSema(Sema *S) {
92  TheSema.reset(S);
93}
94
95void CompilerInstance::setASTConsumer(ASTConsumer *Value) {
96  Consumer.reset(Value);
97}
98
99void CompilerInstance::setCodeCompletionConsumer(CodeCompleteConsumer *Value) {
100  CompletionConsumer.reset(Value);
101}
102
103// Diagnostics
104static void SetUpBuildDumpLog(const DiagnosticOptions &DiagOpts,
105                              unsigned argc, const char* const *argv,
106                              DiagnosticsEngine &Diags) {
107  std::string ErrorInfo;
108  llvm::OwningPtr<raw_ostream> OS(
109    new llvm::raw_fd_ostream(DiagOpts.DumpBuildInformation.c_str(), ErrorInfo));
110  if (!ErrorInfo.empty()) {
111    Diags.Report(diag::err_fe_unable_to_open_logfile)
112                 << DiagOpts.DumpBuildInformation << ErrorInfo;
113    return;
114  }
115
116  (*OS) << "clang -cc1 command line arguments: ";
117  for (unsigned i = 0; i != argc; ++i)
118    (*OS) << argv[i] << ' ';
119  (*OS) << '\n';
120
121  // Chain in a diagnostic client which will log the diagnostics.
122  DiagnosticConsumer *Logger =
123    new TextDiagnosticPrinter(*OS.take(), DiagOpts, /*OwnsOutputStream=*/true);
124  Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(), Logger));
125}
126
127static void SetUpDiagnosticLog(const DiagnosticOptions &DiagOpts,
128                               const CodeGenOptions *CodeGenOpts,
129                               DiagnosticsEngine &Diags) {
130  std::string ErrorInfo;
131  bool OwnsStream = false;
132  raw_ostream *OS = &llvm::errs();
133  if (DiagOpts.DiagnosticLogFile != "-") {
134    // Create the output stream.
135    llvm::raw_fd_ostream *FileOS(
136      new llvm::raw_fd_ostream(DiagOpts.DiagnosticLogFile.c_str(),
137                               ErrorInfo, llvm::raw_fd_ostream::F_Append));
138    if (!ErrorInfo.empty()) {
139      Diags.Report(diag::warn_fe_cc_log_diagnostics_failure)
140        << DiagOpts.DumpBuildInformation << ErrorInfo;
141    } else {
142      FileOS->SetUnbuffered();
143      FileOS->SetUseAtomicWrites(true);
144      OS = FileOS;
145      OwnsStream = true;
146    }
147  }
148
149  // Chain in the diagnostic client which will log the diagnostics.
150  LogDiagnosticPrinter *Logger = new LogDiagnosticPrinter(*OS, DiagOpts,
151                                                          OwnsStream);
152  if (CodeGenOpts)
153    Logger->setDwarfDebugFlags(CodeGenOpts->DwarfDebugFlags);
154  Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(), Logger));
155}
156
157static void SetupSerializedDiagnostics(const DiagnosticOptions &DiagOpts,
158                                       DiagnosticsEngine &Diags,
159                                       StringRef OutputFile) {
160  std::string ErrorInfo;
161  llvm::OwningPtr<llvm::raw_fd_ostream> OS;
162  OS.reset(new llvm::raw_fd_ostream(OutputFile.str().c_str(), ErrorInfo,
163                                    llvm::raw_fd_ostream::F_Binary));
164
165  if (!ErrorInfo.empty()) {
166    Diags.Report(diag::warn_fe_serialized_diag_failure)
167      << OutputFile << ErrorInfo;
168    return;
169  }
170
171  DiagnosticConsumer *SerializedConsumer =
172    clang::serialized_diags::create(OS.take(), Diags);
173
174
175  Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(),
176                                                SerializedConsumer));
177}
178
179void CompilerInstance::createDiagnostics(int Argc, const char* const *Argv,
180                                         DiagnosticConsumer *Client,
181                                         bool ShouldOwnClient,
182                                         bool ShouldCloneClient) {
183  Diagnostics = createDiagnostics(getDiagnosticOpts(), Argc, Argv, Client,
184                                  ShouldOwnClient, ShouldCloneClient,
185                                  &getCodeGenOpts());
186}
187
188llvm::IntrusiveRefCntPtr<DiagnosticsEngine>
189CompilerInstance::createDiagnostics(const DiagnosticOptions &Opts,
190                                    int Argc, const char* const *Argv,
191                                    DiagnosticConsumer *Client,
192                                    bool ShouldOwnClient,
193                                    bool ShouldCloneClient,
194                                    const CodeGenOptions *CodeGenOpts) {
195  llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
196  llvm::IntrusiveRefCntPtr<DiagnosticsEngine>
197      Diags(new DiagnosticsEngine(DiagID));
198
199  // Create the diagnostic client for reporting errors or for
200  // implementing -verify.
201  if (Client) {
202    if (ShouldCloneClient)
203      Diags->setClient(Client->clone(*Diags), ShouldOwnClient);
204    else
205      Diags->setClient(Client, ShouldOwnClient);
206  } else
207    Diags->setClient(new TextDiagnosticPrinter(llvm::errs(), Opts));
208
209  // Chain in -verify checker, if requested.
210  if (Opts.VerifyDiagnostics)
211    Diags->setClient(new VerifyDiagnosticConsumer(*Diags));
212
213  // Chain in -diagnostic-log-file dumper, if requested.
214  if (!Opts.DiagnosticLogFile.empty())
215    SetUpDiagnosticLog(Opts, CodeGenOpts, *Diags);
216
217  if (!Opts.DumpBuildInformation.empty())
218    SetUpBuildDumpLog(Opts, Argc, Argv, *Diags);
219
220  if (!Opts.DiagnosticSerializationFile.empty())
221    SetupSerializedDiagnostics(Opts, *Diags,
222                               Opts.DiagnosticSerializationFile);
223
224  // Configure our handling of diagnostics.
225  ProcessWarningOptions(*Diags, Opts);
226
227  return Diags;
228}
229
230// File Manager
231
232void CompilerInstance::createFileManager() {
233  FileMgr = new FileManager(getFileSystemOpts());
234}
235
236// Source Manager
237
238void CompilerInstance::createSourceManager(FileManager &FileMgr) {
239  SourceMgr = new SourceManager(getDiagnostics(), FileMgr);
240}
241
242// Preprocessor
243
244void CompilerInstance::createPreprocessor() {
245  const PreprocessorOptions &PPOpts = getPreprocessorOpts();
246
247  // Create a PTH manager if we are using some form of a token cache.
248  PTHManager *PTHMgr = 0;
249  if (!PPOpts.TokenCache.empty())
250    PTHMgr = PTHManager::Create(PPOpts.TokenCache, getDiagnostics());
251
252  // Create the Preprocessor.
253  HeaderSearch *HeaderInfo = new HeaderSearch(getFileManager(),
254                                              getDiagnostics());
255  PP = new Preprocessor(getDiagnostics(), getLangOpts(), &getTarget(),
256                        getSourceManager(), *HeaderInfo, *this, PTHMgr,
257                        /*OwnsHeaderSearch=*/true);
258
259  // Note that this is different then passing PTHMgr to Preprocessor's ctor.
260  // That argument is used as the IdentifierInfoLookup argument to
261  // IdentifierTable's ctor.
262  if (PTHMgr) {
263    PTHMgr->setPreprocessor(&*PP);
264    PP->setPTHManager(PTHMgr);
265  }
266
267  if (PPOpts.DetailedRecord)
268    PP->createPreprocessingRecord(
269                                  PPOpts.DetailedRecordIncludesNestedMacroExpansions);
270
271  InitializePreprocessor(*PP, PPOpts, getHeaderSearchOpts(), getFrontendOpts());
272
273  // Set up the module path, including the hash for the
274  // module-creation options.
275  llvm::SmallString<256> SpecificModuleCache(
276                           getHeaderSearchOpts().ModuleCachePath);
277  if (!getHeaderSearchOpts().DisableModuleHash)
278    llvm::sys::path::append(SpecificModuleCache,
279                            getInvocation().getModuleHash());
280  PP->getHeaderSearchInfo().configureModules(SpecificModuleCache,
281                                             getLangOpts().CurrentModule);
282
283  // Handle generating dependencies, if requested.
284  const DependencyOutputOptions &DepOpts = getDependencyOutputOpts();
285  if (!DepOpts.OutputFile.empty())
286    AttachDependencyFileGen(*PP, DepOpts);
287
288  // Handle generating header include information, if requested.
289  if (DepOpts.ShowHeaderIncludes)
290    AttachHeaderIncludeGen(*PP);
291  if (!DepOpts.HeaderIncludeOutputFile.empty()) {
292    StringRef OutputPath = DepOpts.HeaderIncludeOutputFile;
293    if (OutputPath == "-")
294      OutputPath = "";
295    AttachHeaderIncludeGen(*PP, /*ShowAllHeaders=*/true, OutputPath,
296                           /*ShowDepth=*/false);
297  }
298}
299
300// ASTContext
301
302void CompilerInstance::createASTContext() {
303  Preprocessor &PP = getPreprocessor();
304  Context = new ASTContext(getLangOpts(), PP.getSourceManager(),
305                           &getTarget(), PP.getIdentifierTable(),
306                           PP.getSelectorTable(), PP.getBuiltinInfo(),
307                           /*size_reserve=*/ 0);
308}
309
310// ExternalASTSource
311
312void CompilerInstance::createPCHExternalASTSource(StringRef Path,
313                                                  bool DisablePCHValidation,
314                                                  bool DisableStatCache,
315                                                 void *DeserializationListener){
316  llvm::OwningPtr<ExternalASTSource> Source;
317  bool Preamble = getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
318  Source.reset(createPCHExternalASTSource(Path, getHeaderSearchOpts().Sysroot,
319                                          DisablePCHValidation,
320                                          DisableStatCache,
321                                          getPreprocessor(), getASTContext(),
322                                          DeserializationListener,
323                                          Preamble));
324  ModuleManager = static_cast<ASTReader*>(Source.get());
325  getASTContext().setExternalSource(Source);
326}
327
328ExternalASTSource *
329CompilerInstance::createPCHExternalASTSource(StringRef Path,
330                                             const std::string &Sysroot,
331                                             bool DisablePCHValidation,
332                                             bool DisableStatCache,
333                                             Preprocessor &PP,
334                                             ASTContext &Context,
335                                             void *DeserializationListener,
336                                             bool Preamble) {
337  llvm::OwningPtr<ASTReader> Reader;
338  Reader.reset(new ASTReader(PP, Context,
339                             Sysroot.empty() ? "" : Sysroot.c_str(),
340                             DisablePCHValidation, DisableStatCache));
341
342  Reader->setDeserializationListener(
343            static_cast<ASTDeserializationListener *>(DeserializationListener));
344  switch (Reader->ReadAST(Path,
345                          Preamble ? serialization::MK_Preamble
346                                   : serialization::MK_PCH)) {
347  case ASTReader::Success:
348    // Set the predefines buffer as suggested by the PCH reader. Typically, the
349    // predefines buffer will be empty.
350    PP.setPredefines(Reader->getSuggestedPredefines());
351    return Reader.take();
352
353  case ASTReader::Failure:
354    // Unrecoverable failure: don't even try to process the input file.
355    break;
356
357  case ASTReader::IgnorePCH:
358    // No suitable PCH file could be found. Return an error.
359    break;
360  }
361
362  return 0;
363}
364
365// Code Completion
366
367static bool EnableCodeCompletion(Preprocessor &PP,
368                                 const std::string &Filename,
369                                 unsigned Line,
370                                 unsigned Column) {
371  // Tell the source manager to chop off the given file at a specific
372  // line and column.
373  const FileEntry *Entry = PP.getFileManager().getFile(Filename);
374  if (!Entry) {
375    PP.getDiagnostics().Report(diag::err_fe_invalid_code_complete_file)
376      << Filename;
377    return true;
378  }
379
380  // Truncate the named file at the given line/column.
381  PP.SetCodeCompletionPoint(Entry, Line, Column);
382  return false;
383}
384
385void CompilerInstance::createCodeCompletionConsumer() {
386  const ParsedSourceLocation &Loc = getFrontendOpts().CodeCompletionAt;
387  if (!CompletionConsumer) {
388    CompletionConsumer.reset(
389      createCodeCompletionConsumer(getPreprocessor(),
390                                   Loc.FileName, Loc.Line, Loc.Column,
391                                   getFrontendOpts().ShowMacrosInCodeCompletion,
392                             getFrontendOpts().ShowCodePatternsInCodeCompletion,
393                           getFrontendOpts().ShowGlobalSymbolsInCodeCompletion,
394                                   llvm::outs()));
395    if (!CompletionConsumer)
396      return;
397  } else if (EnableCodeCompletion(getPreprocessor(), Loc.FileName,
398                                  Loc.Line, Loc.Column)) {
399    CompletionConsumer.reset();
400    return;
401  }
402
403  if (CompletionConsumer->isOutputBinary() &&
404      llvm::sys::Program::ChangeStdoutToBinary()) {
405    getPreprocessor().getDiagnostics().Report(diag::err_fe_stdout_binary);
406    CompletionConsumer.reset();
407  }
408}
409
410void CompilerInstance::createFrontendTimer() {
411  FrontendTimer.reset(new llvm::Timer("Clang front-end timer"));
412}
413
414CodeCompleteConsumer *
415CompilerInstance::createCodeCompletionConsumer(Preprocessor &PP,
416                                               const std::string &Filename,
417                                               unsigned Line,
418                                               unsigned Column,
419                                               bool ShowMacros,
420                                               bool ShowCodePatterns,
421                                               bool ShowGlobals,
422                                               raw_ostream &OS) {
423  if (EnableCodeCompletion(PP, Filename, Line, Column))
424    return 0;
425
426  // Set up the creation routine for code-completion.
427  return new PrintingCodeCompleteConsumer(ShowMacros, ShowCodePatterns,
428                                          ShowGlobals, OS);
429}
430
431void CompilerInstance::createSema(TranslationUnitKind TUKind,
432                                  CodeCompleteConsumer *CompletionConsumer) {
433  TheSema.reset(new Sema(getPreprocessor(), getASTContext(), getASTConsumer(),
434                         TUKind, CompletionConsumer));
435}
436
437// Output Files
438
439void CompilerInstance::addOutputFile(const OutputFile &OutFile) {
440  assert(OutFile.OS && "Attempt to add empty stream to output list!");
441  OutputFiles.push_back(OutFile);
442}
443
444void CompilerInstance::clearOutputFiles(bool EraseFiles) {
445  for (std::list<OutputFile>::iterator
446         it = OutputFiles.begin(), ie = OutputFiles.end(); it != ie; ++it) {
447    delete it->OS;
448    if (!it->TempFilename.empty()) {
449      if (EraseFiles) {
450        bool existed;
451        llvm::sys::fs::remove(it->TempFilename, existed);
452      } else {
453        llvm::SmallString<128> NewOutFile(it->Filename);
454
455        // If '-working-directory' was passed, the output filename should be
456        // relative to that.
457        FileMgr->FixupRelativePath(NewOutFile);
458        if (llvm::error_code ec = llvm::sys::fs::rename(it->TempFilename,
459                                                        NewOutFile.str())) {
460          getDiagnostics().Report(diag::err_fe_unable_to_rename_temp)
461            << it->TempFilename << it->Filename << ec.message();
462
463          bool existed;
464          llvm::sys::fs::remove(it->TempFilename, existed);
465        }
466      }
467    } else if (!it->Filename.empty() && EraseFiles)
468      llvm::sys::Path(it->Filename).eraseFromDisk();
469
470  }
471  OutputFiles.clear();
472}
473
474llvm::raw_fd_ostream *
475CompilerInstance::createDefaultOutputFile(bool Binary,
476                                          StringRef InFile,
477                                          StringRef Extension) {
478  return createOutputFile(getFrontendOpts().OutputFile, Binary,
479                          /*RemoveFileOnSignal=*/true, InFile, Extension);
480}
481
482llvm::raw_fd_ostream *
483CompilerInstance::createOutputFile(StringRef OutputPath,
484                                   bool Binary, bool RemoveFileOnSignal,
485                                   StringRef InFile,
486                                   StringRef Extension,
487                                   bool UseTemporary) {
488  std::string Error, OutputPathName, TempPathName;
489  llvm::raw_fd_ostream *OS = createOutputFile(OutputPath, Error, Binary,
490                                              RemoveFileOnSignal,
491                                              InFile, Extension,
492                                              UseTemporary,
493                                              &OutputPathName,
494                                              &TempPathName);
495  if (!OS) {
496    getDiagnostics().Report(diag::err_fe_unable_to_open_output)
497      << OutputPath << Error;
498    return 0;
499  }
500
501  // Add the output file -- but don't try to remove "-", since this means we are
502  // using stdin.
503  addOutputFile(OutputFile((OutputPathName != "-") ? OutputPathName : "",
504                TempPathName, OS));
505
506  return OS;
507}
508
509llvm::raw_fd_ostream *
510CompilerInstance::createOutputFile(StringRef OutputPath,
511                                   std::string &Error,
512                                   bool Binary,
513                                   bool RemoveFileOnSignal,
514                                   StringRef InFile,
515                                   StringRef Extension,
516                                   bool UseTemporary,
517                                   std::string *ResultPathName,
518                                   std::string *TempPathName) {
519  std::string OutFile, TempFile;
520  if (!OutputPath.empty()) {
521    OutFile = OutputPath;
522  } else if (InFile == "-") {
523    OutFile = "-";
524  } else if (!Extension.empty()) {
525    llvm::sys::Path Path(InFile);
526    Path.eraseSuffix();
527    Path.appendSuffix(Extension);
528    OutFile = Path.str();
529  } else {
530    OutFile = "-";
531  }
532
533  llvm::OwningPtr<llvm::raw_fd_ostream> OS;
534  std::string OSFile;
535
536  if (UseTemporary && OutFile != "-") {
537    llvm::sys::Path OutPath(OutFile);
538    // Only create the temporary if we can actually write to OutPath, otherwise
539    // we want to fail early.
540    bool Exists;
541    if ((llvm::sys::fs::exists(OutPath.str(), Exists) || !Exists) ||
542        (OutPath.isRegularFile() && OutPath.canWrite())) {
543      // Create a temporary file.
544      llvm::SmallString<128> TempPath;
545      TempPath = OutFile;
546      TempPath += "-%%%%%%%%";
547      int fd;
548      if (llvm::sys::fs::unique_file(TempPath.str(), fd, TempPath,
549                               /*makeAbsolute=*/false) == llvm::errc::success) {
550        OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
551        OSFile = TempFile = TempPath.str();
552      }
553    }
554  }
555
556  if (!OS) {
557    OSFile = OutFile;
558    OS.reset(
559      new llvm::raw_fd_ostream(OSFile.c_str(), Error,
560                               (Binary ? llvm::raw_fd_ostream::F_Binary : 0)));
561    if (!Error.empty())
562      return 0;
563  }
564
565  // Make sure the out stream file gets removed if we crash.
566  if (RemoveFileOnSignal)
567    llvm::sys::RemoveFileOnSignal(llvm::sys::Path(OSFile));
568
569  if (ResultPathName)
570    *ResultPathName = OutFile;
571  if (TempPathName)
572    *TempPathName = TempFile;
573
574  return OS.take();
575}
576
577// Initialization Utilities
578
579bool CompilerInstance::InitializeSourceManager(StringRef InputFile) {
580  return InitializeSourceManager(InputFile, getDiagnostics(), getFileManager(),
581                                 getSourceManager(), getFrontendOpts());
582}
583
584bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
585                                               DiagnosticsEngine &Diags,
586                                               FileManager &FileMgr,
587                                               SourceManager &SourceMgr,
588                                               const FrontendOptions &Opts) {
589  // Figure out where to get and map in the main file.
590  if (InputFile != "-") {
591    const FileEntry *File = FileMgr.getFile(InputFile);
592    if (!File) {
593      Diags.Report(diag::err_fe_error_reading) << InputFile;
594      return false;
595    }
596    SourceMgr.createMainFileID(File);
597  } else {
598    llvm::OwningPtr<llvm::MemoryBuffer> SB;
599    if (llvm::MemoryBuffer::getSTDIN(SB)) {
600      // FIXME: Give ec.message() in this diag.
601      Diags.Report(diag::err_fe_error_reading_stdin);
602      return false;
603    }
604    const FileEntry *File = FileMgr.getVirtualFile(SB->getBufferIdentifier(),
605                                                   SB->getBufferSize(), 0);
606    SourceMgr.createMainFileID(File);
607    SourceMgr.overrideFileContents(File, SB.take());
608  }
609
610  assert(!SourceMgr.getMainFileID().isInvalid() &&
611         "Couldn't establish MainFileID!");
612  return true;
613}
614
615// High-Level Operations
616
617bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
618  assert(hasDiagnostics() && "Diagnostics engine is not initialized!");
619  assert(!getFrontendOpts().ShowHelp && "Client must handle '-help'!");
620  assert(!getFrontendOpts().ShowVersion && "Client must handle '-version'!");
621
622  // FIXME: Take this as an argument, once all the APIs we used have moved to
623  // taking it as an input instead of hard-coding llvm::errs.
624  raw_ostream &OS = llvm::errs();
625
626  // Create the target instance.
627  setTarget(TargetInfo::CreateTargetInfo(getDiagnostics(), getTargetOpts()));
628  if (!hasTarget())
629    return false;
630
631  // Inform the target of the language options.
632  //
633  // FIXME: We shouldn't need to do this, the target should be immutable once
634  // created. This complexity should be lifted elsewhere.
635  getTarget().setForcedLangOptions(getLangOpts());
636
637  // Validate/process some options.
638  if (getHeaderSearchOpts().Verbose)
639    OS << "clang -cc1 version " CLANG_VERSION_STRING
640       << " based upon " << PACKAGE_STRING
641       << " default target " << llvm::sys::getDefaultTargetTriple() << "\n";
642
643  if (getFrontendOpts().ShowTimers)
644    createFrontendTimer();
645
646  if (getFrontendOpts().ShowStats)
647    llvm::EnableStatistics();
648
649  for (unsigned i = 0, e = getFrontendOpts().Inputs.size(); i != e; ++i) {
650    const std::string &InFile = getFrontendOpts().Inputs[i].second;
651
652    // Reset the ID tables if we are reusing the SourceManager.
653    if (hasSourceManager())
654      getSourceManager().clearIDTables();
655
656    if (Act.BeginSourceFile(*this, InFile, getFrontendOpts().Inputs[i].first)) {
657      Act.Execute();
658      Act.EndSourceFile();
659    }
660  }
661
662  if (getDiagnosticOpts().ShowCarets) {
663    // We can have multiple diagnostics sharing one diagnostic client.
664    // Get the total number of warnings/errors from the client.
665    unsigned NumWarnings = getDiagnostics().getClient()->getNumWarnings();
666    unsigned NumErrors = getDiagnostics().getClient()->getNumErrors();
667
668    if (NumWarnings)
669      OS << NumWarnings << " warning" << (NumWarnings == 1 ? "" : "s");
670    if (NumWarnings && NumErrors)
671      OS << " and ";
672    if (NumErrors)
673      OS << NumErrors << " error" << (NumErrors == 1 ? "" : "s");
674    if (NumWarnings || NumErrors)
675      OS << " generated.\n";
676  }
677
678  if (getFrontendOpts().ShowStats && hasFileManager()) {
679    getFileManager().PrintStats();
680    OS << "\n";
681  }
682
683  return !getDiagnostics().getClient()->getNumErrors();
684}
685
686/// \brief Determine the appropriate source input kind based on language
687/// options.
688static InputKind getSourceInputKindFromOptions(const LangOptions &LangOpts) {
689  if (LangOpts.OpenCL)
690    return IK_OpenCL;
691  if (LangOpts.CUDA)
692    return IK_CUDA;
693  if (LangOpts.ObjC1)
694    return LangOpts.CPlusPlus? IK_ObjCXX : IK_ObjC;
695  return LangOpts.CPlusPlus? IK_CXX : IK_C;
696}
697
698namespace {
699  struct CompileModuleData {
700    CompilerInstance &Instance;
701    GeneratePCHAction &CreateModuleAction;
702  };
703}
704
705/// \brief Helper function that executes the module-generating action under
706/// a crash recovery context.
707static void doCompileModule(void *UserData) {
708  CompileModuleData &Data = *reinterpret_cast<CompileModuleData *>(UserData);
709  Data.Instance.ExecuteAction(Data.CreateModuleAction);
710}
711
712namespace {
713  /// \brief Class that manages the creation of a lock file to aid
714  /// implicit coordination between different processes.
715  ///
716  /// The implicit coordination works by creating a ".lock" file alongside
717  /// the file that we're coordinating for, using the atomicity of the file
718  /// system to ensure that only a single process can create that ".lock" file.
719  /// When the lock file is removed, the owning process has finished the
720  /// operation.
721  class LockFileManager {
722  public:
723    /// \brief Describes the state of a lock file.
724    enum LockFileState {
725      /// \brief The lock file has been created and is owned by this instance
726      /// of the object.
727      LFS_Owned,
728      /// \brief The lock file already exists and is owned by some other
729      /// instance.
730      LFS_Shared,
731      /// \brief An error occurred while trying to create or find the lock
732      /// file.
733      LFS_Error
734    };
735
736  private:
737    llvm::SmallString<128> LockFileName;
738    llvm::SmallString<128> UniqueLockFileName;
739
740    llvm::Optional<std::pair<std::string, int> > Owner;
741    llvm::Optional<llvm::error_code> Error;
742
743    LockFileManager(const LockFileManager &);
744    LockFileManager &operator=(const LockFileManager &);
745
746    static llvm::Optional<std::pair<std::string, int> >
747    readLockFile(StringRef LockFileName);
748
749    static bool processStillExecuting(StringRef Hostname, int PID);
750
751  public:
752
753    LockFileManager(StringRef FileName);
754    ~LockFileManager();
755
756    /// \brief Determine the state of the lock file.
757    LockFileState getState() const;
758
759    operator LockFileState() const { return getState(); }
760
761    /// \brief For a shared lock, wait until the owner releases the lock.
762    void waitForUnlock();
763  };
764}
765
766/// \brief Attempt to read the lock file with the given name, if it exists.
767///
768/// \param LockFileName The name of the lock file to read.
769///
770/// \returns The process ID of the process that owns this lock file
771llvm::Optional<std::pair<std::string, int> >
772LockFileManager::readLockFile(StringRef LockFileName) {
773  // Check whether the lock file exists. If not, clearly there's nothing
774  // to read, so we just return.
775  bool Exists = false;
776  if (llvm::sys::fs::exists(LockFileName, Exists) || !Exists)
777    return llvm::Optional<std::pair<std::string, int> >();
778
779  // Read the owning host and PID out of the lock file. If it appears that the
780  // owning process is dead, the lock file is invalid.
781  int PID = 0;
782  std::string Hostname;
783  std::ifstream Input(LockFileName.str().c_str());
784  if (Input >> Hostname >> PID && PID > 0 &&
785      processStillExecuting(Hostname, PID))
786    return std::make_pair(Hostname, PID);
787
788  // Delete the lock file. It's invalid anyway.
789  bool Existed;
790  llvm::sys::fs::remove(LockFileName, Existed);
791  return llvm::Optional<std::pair<std::string, int> >();
792}
793
794bool LockFileManager::processStillExecuting(StringRef Hostname, int PID) {
795#if LLVM_ON_UNIX
796  char MyHostname[256];
797  MyHostname[255] = 0;
798  MyHostname[0] = 0;
799  gethostname(MyHostname, 255);
800  // Check whether the process is dead. If so, we're done.
801  if (MyHostname == Hostname && getsid(PID) == -1 && errno == ESRCH)
802    return false;
803#endif
804
805  return true;
806}
807
808LockFileManager::LockFileManager(StringRef FileName)
809{
810  LockFileName = FileName;
811  LockFileName += ".lock";
812
813  // If the lock file already exists, don't bother to try to create our own
814  // lock file; it won't work anyway. Just figure out who owns this lock file.
815  if ((Owner = readLockFile(LockFileName)))
816    return;
817
818  // Create a lock file that is unique to this instance.
819  UniqueLockFileName = LockFileName;
820  UniqueLockFileName += "-%%%%%%%%";
821  int UniqueLockFileID;
822  if (llvm::error_code EC
823        = llvm::sys::fs::unique_file(UniqueLockFileName.str(),
824                                     UniqueLockFileID,
825                                     UniqueLockFileName,
826                                     /*makeAbsolute=*/false)) {
827    Error = EC;
828    return;
829  }
830
831  // Write our process ID to our unique lock file.
832  {
833    llvm::raw_fd_ostream Out(UniqueLockFileID, /*shouldClose=*/true);
834
835#if LLVM_ON_UNIX
836    // FIXME: move getpid() call into LLVM
837    char hostname[256];
838    hostname[255] = 0;
839    hostname[0] = 0;
840    gethostname(hostname, 255);
841    Out << hostname << ' ' << getpid();
842#else
843    Out << "localhost 1";
844#endif
845    Out.close();
846
847    if (Out.has_error()) {
848      // We failed to write out PID, so make up an excuse, remove the
849      // unique lock file, and fail.
850      Error = llvm::make_error_code(llvm::errc::no_space_on_device);
851      bool Existed;
852      llvm::sys::fs::remove(UniqueLockFileName.c_str(), Existed);
853      return;
854    }
855  }
856
857  // Create a hard link from the lock file name. If this succeeds, we're done.
858  llvm::error_code EC
859    = llvm::sys::fs::create_hard_link(UniqueLockFileName.str(),
860                                      LockFileName.str());
861  if (EC == llvm::errc::success)
862    return;
863
864  // Creating the hard link failed.
865
866#ifdef LLVM_ON_UNIX
867  // The creation of the hard link may appear to fail, but if stat'ing the
868  // unique file returns a link count of 2, then we can still declare success.
869  struct stat StatBuf;
870  if (stat(UniqueLockFileName.c_str(), &StatBuf) == 0 &&
871      StatBuf.st_nlink == 2)
872    return;
873#endif
874
875  // Someone else managed to create the lock file first. Wipe out our unique
876  // lock file (it's useless now) and read the process ID from the lock file.
877  bool Existed;
878  llvm::sys::fs::remove(UniqueLockFileName.str(), Existed);
879  if ((Owner = readLockFile(LockFileName)))
880    return;
881
882  // There is a lock file that nobody owns; try to clean it up and report
883  // an error.
884  llvm::sys::fs::remove(LockFileName.str(), Existed);
885  Error = EC;
886}
887
888LockFileManager::LockFileState LockFileManager::getState() const {
889  if (Owner)
890    return LFS_Shared;
891
892  if (Error)
893    return LFS_Error;
894
895  return LFS_Owned;
896}
897
898LockFileManager::~LockFileManager() {
899  if (getState() != LFS_Owned)
900    return;
901
902  // Since we own the lock, remove the lock file and our own unique lock file.
903  bool Existed;
904  llvm::sys::fs::remove(LockFileName.str(), Existed);
905  llvm::sys::fs::remove(UniqueLockFileName.str(), Existed);
906}
907
908void LockFileManager::waitForUnlock() {
909  if (getState() != LFS_Shared)
910    return;
911
912#if LLVM_ON_WIN32
913  unsigned long Interval = 1;
914#else
915  struct timespec Interval;
916  Interval.tv_sec = 0;
917  Interval.tv_nsec = 1000000;
918#endif
919  // Don't wait more than an hour for the file to appear.
920  const unsigned MaxSeconds = 3600;
921  do {
922    // Sleep for the designated interval, to allow the owning process time to
923    // finish up and
924    // FIXME: Should we hook in to system APIs to get a notification when the
925    // lock file is deleted?
926#if LLVM_ON_WIN32
927    Sleep(Interval);
928#else
929    nanosleep(&Interval, NULL);
930#endif
931    // If the file no longer exists, we're done.
932    bool Exists = false;
933    if (!llvm::sys::fs::exists(LockFileName.str(), Exists) && !Exists)
934      return;
935
936    if (!processStillExecuting((*Owner).first, (*Owner).second))
937      return;
938
939    // Exponentially increase the time we wait for the lock to be removed.
940#if LLVM_ON_WIN32
941    Interval *= 2;
942#else
943    Interval.tv_sec *= 2;
944    Interval.tv_nsec *= 2;
945    if (Interval.tv_nsec >= 1000000000) {
946      ++Interval.tv_sec;
947      Interval.tv_nsec -= 1000000000;
948    }
949#endif
950  } while (
951#if LLVM_ON_WIN32
952           Interval < MaxSeconds * 1000
953#else
954           Interval.tv_sec < (time_t)MaxSeconds
955#endif
956           );
957
958  // Give up.
959}
960
961/// \brief Compile a module file for the given module name with the given
962/// umbrella header, using the options provided by the importing compiler
963/// instance.
964static void compileModule(CompilerInstance &ImportingInstance,
965                          StringRef ModuleName,
966                          StringRef ModuleFileName,
967                          StringRef UmbrellaHeader) {
968  LockFileManager Locked(ModuleFileName);
969  switch (Locked) {
970  case LockFileManager::LFS_Error:
971    return;
972
973  case LockFileManager::LFS_Owned:
974    // We're responsible for building the module ourselves. Do so below.
975    break;
976
977  case LockFileManager::LFS_Shared:
978    // Someone else is responsible for building the module. Wait for them to
979    // finish.
980    Locked.waitForUnlock();
981    break;
982  }
983
984  // Construct a compiler invocation for creating this module.
985  llvm::IntrusiveRefCntPtr<CompilerInvocation> Invocation
986    (new CompilerInvocation(ImportingInstance.getInvocation()));
987
988  // For any options that aren't intended to affect how a module is built,
989  // reset them to their default values.
990  Invocation->getLangOpts().resetNonModularOptions();
991  Invocation->getPreprocessorOpts().resetNonModularOptions();
992
993  // Note the name of the module we're building.
994  Invocation->getLangOpts().CurrentModule = ModuleName;
995
996  // Note that this module is part of the module build path, so that we
997  // can detect cycles in the module graph.
998  Invocation->getPreprocessorOpts().ModuleBuildPath.push_back(ModuleName);
999
1000  // Set up the inputs/outputs so that we build the module from its umbrella
1001  // header.
1002  FrontendOptions &FrontendOpts = Invocation->getFrontendOpts();
1003  FrontendOpts.OutputFile = ModuleFileName.str();
1004  FrontendOpts.DisableFree = false;
1005  FrontendOpts.Inputs.clear();
1006  FrontendOpts.Inputs.push_back(
1007    std::make_pair(getSourceInputKindFromOptions(Invocation->getLangOpts()),
1008                                                 UmbrellaHeader));
1009
1010  Invocation->getDiagnosticOpts().VerifyDiagnostics = 0;
1011
1012
1013  assert(ImportingInstance.getInvocation().getModuleHash() ==
1014           Invocation->getModuleHash() && "Module hash mismatch!");
1015
1016  // Construct a compiler instance that will be used to actually create the
1017  // module.
1018  CompilerInstance Instance;
1019  Instance.setInvocation(&*Invocation);
1020  Instance.createDiagnostics(/*argc=*/0, /*argv=*/0,
1021                             &ImportingInstance.getDiagnosticClient(),
1022                             /*ShouldOwnClient=*/true,
1023                             /*ShouldCloneClient=*/true);
1024
1025  // Construct a module-generating action.
1026  GeneratePCHAction CreateModuleAction(true);
1027
1028  // Execute the action to actually build the module in-place. Use a separate
1029  // thread so that we get a stack large enough.
1030  const unsigned ThreadStackSize = 8 << 20;
1031  llvm::CrashRecoveryContext CRC;
1032  CompileModuleData Data = { Instance, CreateModuleAction };
1033  CRC.RunSafelyOnThread(&doCompileModule, &Data, ThreadStackSize);
1034}
1035
1036ModuleKey CompilerInstance::loadModule(SourceLocation ImportLoc,
1037                                       IdentifierInfo &ModuleName,
1038                                       SourceLocation ModuleNameLoc) {
1039  // Determine what file we're searching from.
1040  SourceManager &SourceMgr = getSourceManager();
1041  SourceLocation ExpandedImportLoc = SourceMgr.getExpansionLoc(ImportLoc);
1042  const FileEntry *CurFile
1043    = SourceMgr.getFileEntryForID(SourceMgr.getFileID(ExpandedImportLoc));
1044  if (!CurFile)
1045    CurFile = SourceMgr.getFileEntryForID(SourceMgr.getMainFileID());
1046
1047  // Search for a module with the given name.
1048  std::string UmbrellaHeader;
1049  std::string ModuleFileName;
1050  const FileEntry *ModuleFile
1051    = PP->getHeaderSearchInfo().lookupModule(ModuleName.getName(),
1052                                             &ModuleFileName,
1053                                             &UmbrellaHeader);
1054
1055  bool BuildingModule = false;
1056  if (!ModuleFile && !UmbrellaHeader.empty()) {
1057    // We didn't find the module, but there is an umbrella header that
1058    // can be used to create the module file. Create a separate compilation
1059    // module to do so.
1060
1061    // Check whether there is a cycle in the module graph.
1062    SmallVectorImpl<std::string> &ModuleBuildPath
1063      = getPreprocessorOpts().ModuleBuildPath;
1064    SmallVectorImpl<std::string>::iterator Pos
1065      = std::find(ModuleBuildPath.begin(), ModuleBuildPath.end(),
1066                  ModuleName.getName());
1067    if (Pos != ModuleBuildPath.end()) {
1068      llvm::SmallString<256> CyclePath;
1069      for (; Pos != ModuleBuildPath.end(); ++Pos) {
1070        CyclePath += *Pos;
1071        CyclePath += " -> ";
1072      }
1073      CyclePath += ModuleName.getName();
1074
1075      getDiagnostics().Report(ModuleNameLoc, diag::err_module_cycle)
1076        << ModuleName.getName() << CyclePath;
1077      return 0;
1078    }
1079
1080    getDiagnostics().Report(ModuleNameLoc, diag::warn_module_build)
1081      << ModuleName.getName();
1082    BuildingModule = true;
1083    compileModule(*this, ModuleName.getName(), ModuleFileName, UmbrellaHeader);
1084    ModuleFile = PP->getHeaderSearchInfo().lookupModule(ModuleName.getName());
1085  }
1086
1087  if (!ModuleFile) {
1088    getDiagnostics().Report(ModuleNameLoc,
1089                            BuildingModule? diag::err_module_not_built
1090                                          : diag::err_module_not_found)
1091      << ModuleName.getName()
1092      << SourceRange(ImportLoc, ModuleNameLoc);
1093    return 0;
1094  }
1095
1096  // If we don't already have an ASTReader, create one now.
1097  if (!ModuleManager) {
1098    if (!hasASTContext())
1099      createASTContext();
1100
1101    std::string Sysroot = getHeaderSearchOpts().Sysroot;
1102    const PreprocessorOptions &PPOpts = getPreprocessorOpts();
1103    ModuleManager = new ASTReader(getPreprocessor(), *Context,
1104                                  Sysroot.empty() ? "" : Sysroot.c_str(),
1105                                  PPOpts.DisablePCHValidation,
1106                                  PPOpts.DisableStatCache);
1107    if (hasASTConsumer()) {
1108      ModuleManager->setDeserializationListener(
1109        getASTConsumer().GetASTDeserializationListener());
1110      getASTContext().setASTMutationListener(
1111        getASTConsumer().GetASTMutationListener());
1112    }
1113    llvm::OwningPtr<ExternalASTSource> Source;
1114    Source.reset(ModuleManager);
1115    getASTContext().setExternalSource(Source);
1116    if (hasSema())
1117      ModuleManager->InitializeSema(getSema());
1118    if (hasASTConsumer())
1119      ModuleManager->StartTranslationUnit(&getASTConsumer());
1120  }
1121
1122  // Try to load the module we found.
1123  switch (ModuleManager->ReadAST(ModuleFile->getName(),
1124                                 serialization::MK_Module)) {
1125  case ASTReader::Success:
1126    break;
1127
1128  case ASTReader::IgnorePCH:
1129    // FIXME: The ASTReader will already have complained, but can we showhorn
1130    // that diagnostic information into a more useful form?
1131    return 0;
1132
1133  case ASTReader::Failure:
1134    // Already complained.
1135    return 0;
1136  }
1137
1138  // FIXME: The module file's FileEntry makes a poor key indeed!
1139  return (ModuleKey)ModuleFile;
1140}
1141
1142