1//===--- Tooling.cpp - Running clang standalone tools ---------------------===//
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 implements functions to run clang tools standalone instead
11//  of running them as a plugin.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/Tooling/Tooling.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/Driver/Compilation.h"
18#include "clang/Driver/Driver.h"
19#include "clang/Driver/Tool.h"
20#include "clang/Frontend/ASTUnit.h"
21#include "clang/Frontend/CompilerInstance.h"
22#include "clang/Frontend/FrontendDiagnostic.h"
23#include "clang/Frontend/TextDiagnosticPrinter.h"
24#include "clang/Tooling/ArgumentsAdjusters.h"
25#include "clang/Tooling/CompilationDatabase.h"
26#include "llvm/ADT/STLExtras.h"
27#include "llvm/Config/llvm-config.h"
28#include "llvm/Option/Option.h"
29#include "llvm/Support/Debug.h"
30#include "llvm/Support/FileSystem.h"
31#include "llvm/Support/Host.h"
32#include "llvm/Support/raw_ostream.h"
33
34// For chdir, see the comment in ClangTool::run for more information.
35#ifdef LLVM_ON_WIN32
36#  include <direct.h>
37#else
38#  include <unistd.h>
39#endif
40
41#define DEBUG_TYPE "clang-tooling"
42
43namespace clang {
44namespace tooling {
45
46ToolAction::~ToolAction() {}
47
48FrontendActionFactory::~FrontendActionFactory() {}
49
50// FIXME: This file contains structural duplication with other parts of the
51// code that sets up a compiler to run tools on it, and we should refactor
52// it to be based on the same framework.
53
54/// \brief Builds a clang driver initialized for running clang tools.
55static clang::driver::Driver *newDriver(clang::DiagnosticsEngine *Diagnostics,
56                                        const char *BinaryName) {
57  clang::driver::Driver *CompilerDriver = new clang::driver::Driver(
58      BinaryName, llvm::sys::getDefaultTargetTriple(), *Diagnostics);
59  CompilerDriver->setTitle("clang_based_tool");
60  return CompilerDriver;
61}
62
63/// \brief Retrieves the clang CC1 specific flags out of the compilation's jobs.
64///
65/// Returns NULL on error.
66static const llvm::opt::ArgStringList *getCC1Arguments(
67    clang::DiagnosticsEngine *Diagnostics,
68    clang::driver::Compilation *Compilation) {
69  // We expect to get back exactly one Command job, if we didn't something
70  // failed. Extract that job from the Compilation.
71  const clang::driver::JobList &Jobs = Compilation->getJobs();
72  if (Jobs.size() != 1 || !isa<clang::driver::Command>(*Jobs.begin())) {
73    SmallString<256> error_msg;
74    llvm::raw_svector_ostream error_stream(error_msg);
75    Jobs.Print(error_stream, "; ", true);
76    Diagnostics->Report(clang::diag::err_fe_expected_compiler_job)
77        << error_stream.str();
78    return nullptr;
79  }
80
81  // The one job we find should be to invoke clang again.
82  const clang::driver::Command &Cmd =
83      cast<clang::driver::Command>(*Jobs.begin());
84  if (StringRef(Cmd.getCreator().getName()) != "clang") {
85    Diagnostics->Report(clang::diag::err_fe_expected_clang_command);
86    return nullptr;
87  }
88
89  return &Cmd.getArguments();
90}
91
92/// \brief Returns a clang build invocation initialized from the CC1 flags.
93clang::CompilerInvocation *newInvocation(
94    clang::DiagnosticsEngine *Diagnostics,
95    const llvm::opt::ArgStringList &CC1Args) {
96  assert(!CC1Args.empty() && "Must at least contain the program name!");
97  clang::CompilerInvocation *Invocation = new clang::CompilerInvocation;
98  clang::CompilerInvocation::CreateFromArgs(
99      *Invocation, CC1Args.data() + 1, CC1Args.data() + CC1Args.size(),
100      *Diagnostics);
101  Invocation->getFrontendOpts().DisableFree = false;
102  Invocation->getCodeGenOpts().DisableFree = false;
103  Invocation->getDependencyOutputOpts() = DependencyOutputOptions();
104  return Invocation;
105}
106
107bool runToolOnCode(clang::FrontendAction *ToolAction, const Twine &Code,
108                   const Twine &FileName) {
109  return runToolOnCodeWithArgs(
110      ToolAction, Code, std::vector<std::string>(), FileName);
111}
112
113static std::vector<std::string>
114getSyntaxOnlyToolArgs(const std::vector<std::string> &ExtraArgs,
115                      StringRef FileName) {
116  std::vector<std::string> Args;
117  Args.push_back("clang-tool");
118  Args.push_back("-fsyntax-only");
119  Args.insert(Args.end(), ExtraArgs.begin(), ExtraArgs.end());
120  Args.push_back(FileName.str());
121  return Args;
122}
123
124bool runToolOnCodeWithArgs(clang::FrontendAction *ToolAction, const Twine &Code,
125                           const std::vector<std::string> &Args,
126                           const Twine &FileName,
127                           const FileContentMappings &VirtualMappedFiles) {
128
129  SmallString<16> FileNameStorage;
130  StringRef FileNameRef = FileName.toNullTerminatedStringRef(FileNameStorage);
131  llvm::IntrusiveRefCntPtr<FileManager> Files(
132      new FileManager(FileSystemOptions()));
133  ToolInvocation Invocation(getSyntaxOnlyToolArgs(Args, FileNameRef),
134                            ToolAction, Files.get());
135
136  SmallString<1024> CodeStorage;
137  Invocation.mapVirtualFile(FileNameRef,
138                            Code.toNullTerminatedStringRef(CodeStorage));
139
140  for (auto &FilenameWithContent : VirtualMappedFiles) {
141    Invocation.mapVirtualFile(FilenameWithContent.first,
142                              FilenameWithContent.second);
143  }
144
145  return Invocation.run();
146}
147
148std::string getAbsolutePath(StringRef File) {
149  StringRef RelativePath(File);
150  // FIXME: Should '.\\' be accepted on Win32?
151  if (RelativePath.startswith("./")) {
152    RelativePath = RelativePath.substr(strlen("./"));
153  }
154
155  SmallString<1024> AbsolutePath = RelativePath;
156  std::error_code EC = llvm::sys::fs::make_absolute(AbsolutePath);
157  assert(!EC);
158  (void)EC;
159  llvm::sys::path::native(AbsolutePath);
160  return AbsolutePath.str();
161}
162
163namespace {
164
165class SingleFrontendActionFactory : public FrontendActionFactory {
166  FrontendAction *Action;
167
168public:
169  SingleFrontendActionFactory(FrontendAction *Action) : Action(Action) {}
170
171  FrontendAction *create() override { return Action; }
172};
173
174}
175
176ToolInvocation::ToolInvocation(std::vector<std::string> CommandLine,
177                               ToolAction *Action, FileManager *Files)
178    : CommandLine(std::move(CommandLine)),
179      Action(Action),
180      OwnsAction(false),
181      Files(Files),
182      DiagConsumer(nullptr) {}
183
184ToolInvocation::ToolInvocation(std::vector<std::string> CommandLine,
185                               FrontendAction *FAction, FileManager *Files)
186    : CommandLine(std::move(CommandLine)),
187      Action(new SingleFrontendActionFactory(FAction)),
188      OwnsAction(true),
189      Files(Files),
190      DiagConsumer(nullptr) {}
191
192ToolInvocation::~ToolInvocation() {
193  if (OwnsAction)
194    delete Action;
195}
196
197void ToolInvocation::mapVirtualFile(StringRef FilePath, StringRef Content) {
198  SmallString<1024> PathStorage;
199  llvm::sys::path::native(FilePath, PathStorage);
200  MappedFileContents[PathStorage] = Content;
201}
202
203bool ToolInvocation::run() {
204  std::vector<const char*> Argv;
205  for (const std::string &Str : CommandLine)
206    Argv.push_back(Str.c_str());
207  const char *const BinaryName = Argv[0];
208  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
209  TextDiagnosticPrinter DiagnosticPrinter(
210      llvm::errs(), &*DiagOpts);
211  DiagnosticsEngine Diagnostics(
212      IntrusiveRefCntPtr<clang::DiagnosticIDs>(new DiagnosticIDs()), &*DiagOpts,
213      DiagConsumer ? DiagConsumer : &DiagnosticPrinter, false);
214
215  const std::unique_ptr<clang::driver::Driver> Driver(
216      newDriver(&Diagnostics, BinaryName));
217  // Since the input might only be virtual, don't check whether it exists.
218  Driver->setCheckInputsExist(false);
219  const std::unique_ptr<clang::driver::Compilation> Compilation(
220      Driver->BuildCompilation(llvm::makeArrayRef(Argv)));
221  const llvm::opt::ArgStringList *const CC1Args = getCC1Arguments(
222      &Diagnostics, Compilation.get());
223  if (!CC1Args) {
224    return false;
225  }
226  std::unique_ptr<clang::CompilerInvocation> Invocation(
227      newInvocation(&Diagnostics, *CC1Args));
228  for (const auto &It : MappedFileContents) {
229    // Inject the code as the given file name into the preprocessor options.
230    std::unique_ptr<llvm::MemoryBuffer> Input =
231        llvm::MemoryBuffer::getMemBuffer(It.getValue());
232    Invocation->getPreprocessorOpts().addRemappedFile(It.getKey(),
233                                                      Input.release());
234  }
235  return runInvocation(BinaryName, Compilation.get(), Invocation.release());
236}
237
238bool ToolInvocation::runInvocation(
239    const char *BinaryName,
240    clang::driver::Compilation *Compilation,
241    clang::CompilerInvocation *Invocation) {
242  // Show the invocation, with -v.
243  if (Invocation->getHeaderSearchOpts().Verbose) {
244    llvm::errs() << "clang Invocation:\n";
245    Compilation->getJobs().Print(llvm::errs(), "\n", true);
246    llvm::errs() << "\n";
247  }
248
249  return Action->runInvocation(Invocation, Files, DiagConsumer);
250}
251
252bool FrontendActionFactory::runInvocation(CompilerInvocation *Invocation,
253                                          FileManager *Files,
254                                          DiagnosticConsumer *DiagConsumer) {
255  // Create a compiler instance to handle the actual work.
256  clang::CompilerInstance Compiler;
257  Compiler.setInvocation(Invocation);
258  Compiler.setFileManager(Files);
259
260  // The FrontendAction can have lifetime requirements for Compiler or its
261  // members, and we need to ensure it's deleted earlier than Compiler. So we
262  // pass it to an std::unique_ptr declared after the Compiler variable.
263  std::unique_ptr<FrontendAction> ScopedToolAction(create());
264
265  // Create the compiler's actual diagnostics engine.
266  Compiler.createDiagnostics(DiagConsumer, /*ShouldOwnClient=*/false);
267  if (!Compiler.hasDiagnostics())
268    return false;
269
270  Compiler.createSourceManager(*Files);
271
272  const bool Success = Compiler.ExecuteAction(*ScopedToolAction);
273
274  Files->clearStatCaches();
275  return Success;
276}
277
278ClangTool::ClangTool(const CompilationDatabase &Compilations,
279                     ArrayRef<std::string> SourcePaths)
280    : Compilations(Compilations), SourcePaths(SourcePaths),
281      Files(new FileManager(FileSystemOptions())), DiagConsumer(nullptr) {
282  appendArgumentsAdjuster(getClangStripOutputAdjuster());
283  appendArgumentsAdjuster(getClangSyntaxOnlyAdjuster());
284}
285
286ClangTool::~ClangTool() {}
287
288void ClangTool::mapVirtualFile(StringRef FilePath, StringRef Content) {
289  MappedFileContents.push_back(std::make_pair(FilePath, Content));
290}
291
292void ClangTool::appendArgumentsAdjuster(ArgumentsAdjuster Adjuster) {
293  if (ArgsAdjuster)
294    ArgsAdjuster = combineAdjusters(ArgsAdjuster, Adjuster);
295  else
296    ArgsAdjuster = Adjuster;
297}
298
299void ClangTool::clearArgumentsAdjusters() {
300  ArgsAdjuster = nullptr;
301}
302
303int ClangTool::run(ToolAction *Action) {
304  // Exists solely for the purpose of lookup of the resource path.
305  // This just needs to be some symbol in the binary.
306  static int StaticSymbol;
307  // The driver detects the builtin header path based on the path of the
308  // executable.
309  // FIXME: On linux, GetMainExecutable is independent of the value of the
310  // first argument, thus allowing ClangTool and runToolOnCode to just
311  // pass in made-up names here. Make sure this works on other platforms.
312  std::string MainExecutable =
313      llvm::sys::fs::getMainExecutable("clang_tool", &StaticSymbol);
314
315  llvm::SmallString<128> InitialDirectory;
316  if (std::error_code EC = llvm::sys::fs::current_path(InitialDirectory))
317    llvm::report_fatal_error("Cannot detect current path: " +
318                             Twine(EC.message()));
319  bool ProcessingFailed = false;
320  for (const auto &SourcePath : SourcePaths) {
321    std::string File(getAbsolutePath(SourcePath));
322
323    // Currently implementations of CompilationDatabase::getCompileCommands can
324    // change the state of the file system (e.g.  prepare generated headers), so
325    // this method needs to run right before we invoke the tool, as the next
326    // file may require a different (incompatible) state of the file system.
327    //
328    // FIXME: Make the compilation database interface more explicit about the
329    // requirements to the order of invocation of its members.
330    std::vector<CompileCommand> CompileCommandsForFile =
331        Compilations.getCompileCommands(File);
332    if (CompileCommandsForFile.empty()) {
333      // FIXME: There are two use cases here: doing a fuzzy
334      // "find . -name '*.cc' |xargs tool" match, where as a user I don't care
335      // about the .cc files that were not found, and the use case where I
336      // specify all files I want to run over explicitly, where this should
337      // be an error. We'll want to add an option for this.
338      llvm::errs() << "Skipping " << File << ". Compile command not found.\n";
339      continue;
340    }
341    for (CompileCommand &CompileCommand : CompileCommandsForFile) {
342      // FIXME: chdir is thread hostile; on the other hand, creating the same
343      // behavior as chdir is complex: chdir resolves the path once, thus
344      // guaranteeing that all subsequent relative path operations work
345      // on the same path the original chdir resulted in. This makes a
346      // difference for example on network filesystems, where symlinks might be
347      // switched during runtime of the tool. Fixing this depends on having a
348      // file system abstraction that allows openat() style interactions.
349      if (chdir(CompileCommand.Directory.c_str()))
350        llvm::report_fatal_error("Cannot chdir into \"" +
351                                 Twine(CompileCommand.Directory) + "\n!");
352      std::vector<std::string> CommandLine = CompileCommand.CommandLine;
353      if (ArgsAdjuster)
354        CommandLine = ArgsAdjuster(CommandLine);
355      assert(!CommandLine.empty());
356      CommandLine[0] = MainExecutable;
357      // FIXME: We need a callback mechanism for the tool writer to output a
358      // customized message for each file.
359      DEBUG({ llvm::dbgs() << "Processing: " << File << ".\n"; });
360      ToolInvocation Invocation(std::move(CommandLine), Action, Files.get());
361      Invocation.setDiagnosticConsumer(DiagConsumer);
362      for (const auto &MappedFile : MappedFileContents)
363        Invocation.mapVirtualFile(MappedFile.first, MappedFile.second);
364      if (!Invocation.run()) {
365        // FIXME: Diagnostics should be used instead.
366        llvm::errs() << "Error while processing " << File << ".\n";
367        ProcessingFailed = true;
368      }
369      // Return to the initial directory to correctly resolve next file by
370      // relative path.
371      if (chdir(InitialDirectory.c_str()))
372        llvm::report_fatal_error("Cannot chdir into \"" +
373                                 Twine(InitialDirectory) + "\n!");
374    }
375  }
376  return ProcessingFailed ? 1 : 0;
377}
378
379namespace {
380
381class ASTBuilderAction : public ToolAction {
382  std::vector<std::unique_ptr<ASTUnit>> &ASTs;
383
384public:
385  ASTBuilderAction(std::vector<std::unique_ptr<ASTUnit>> &ASTs) : ASTs(ASTs) {}
386
387  bool runInvocation(CompilerInvocation *Invocation, FileManager *Files,
388                     DiagnosticConsumer *DiagConsumer) override {
389    // FIXME: This should use the provided FileManager.
390    std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromCompilerInvocation(
391        Invocation, CompilerInstance::createDiagnostics(
392                        &Invocation->getDiagnosticOpts(), DiagConsumer,
393                        /*ShouldOwnClient=*/false));
394    if (!AST)
395      return false;
396
397    ASTs.push_back(std::move(AST));
398    return true;
399  }
400};
401
402}
403
404int ClangTool::buildASTs(std::vector<std::unique_ptr<ASTUnit>> &ASTs) {
405  ASTBuilderAction Action(ASTs);
406  return run(&Action);
407}
408
409std::unique_ptr<ASTUnit> buildASTFromCode(const Twine &Code,
410                                          const Twine &FileName) {
411  return buildASTFromCodeWithArgs(Code, std::vector<std::string>(), FileName);
412}
413
414std::unique_ptr<ASTUnit>
415buildASTFromCodeWithArgs(const Twine &Code,
416                         const std::vector<std::string> &Args,
417                         const Twine &FileName) {
418  SmallString<16> FileNameStorage;
419  StringRef FileNameRef = FileName.toNullTerminatedStringRef(FileNameStorage);
420
421  std::vector<std::unique_ptr<ASTUnit>> ASTs;
422  ASTBuilderAction Action(ASTs);
423  ToolInvocation Invocation(getSyntaxOnlyToolArgs(Args, FileNameRef), &Action,
424                            nullptr);
425
426  SmallString<1024> CodeStorage;
427  Invocation.mapVirtualFile(FileNameRef,
428                            Code.toNullTerminatedStringRef(CodeStorage));
429  if (!Invocation.run())
430    return nullptr;
431
432  assert(ASTs.size() == 1);
433  return std::move(ASTs[0]);
434}
435
436} // end namespace tooling
437} // end namespace clang
438