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/ArgumentsAdjusters.h"
16#include "clang/Tooling/Tooling.h"
17#include "clang/Tooling/CompilationDatabase.h"
18#include "clang/Driver/Compilation.h"
19#include "clang/Driver/Driver.h"
20#include "clang/Driver/Tool.h"
21#include "clang/Frontend/CompilerInstance.h"
22#include "clang/Frontend/FrontendDiagnostic.h"
23#include "clang/Frontend/TextDiagnosticPrinter.h"
24#include "llvm/ADT/STLExtras.h"
25#include "llvm/Support/FileSystem.h"
26#include "llvm/Support/Host.h"
27#include "llvm/Support/raw_ostream.h"
28
29// For chdir, see the comment in ClangTool::run for more information.
30#ifdef _WIN32
31#  include <direct.h>
32#else
33#  include <unistd.h>
34#endif
35
36namespace clang {
37namespace tooling {
38
39FrontendActionFactory::~FrontendActionFactory() {}
40
41// FIXME: This file contains structural duplication with other parts of the
42// code that sets up a compiler to run tools on it, and we should refactor
43// it to be based on the same framework.
44
45/// \brief Builds a clang driver initialized for running clang tools.
46static clang::driver::Driver *newDriver(clang::DiagnosticsEngine *Diagnostics,
47                                        const char *BinaryName) {
48  const std::string DefaultOutputName = "a.out";
49  clang::driver::Driver *CompilerDriver = new clang::driver::Driver(
50    BinaryName, llvm::sys::getDefaultTargetTriple(),
51    DefaultOutputName, false, *Diagnostics);
52  CompilerDriver->setTitle("clang_based_tool");
53  return CompilerDriver;
54}
55
56/// \brief Retrieves the clang CC1 specific flags out of the compilation's jobs.
57///
58/// Returns NULL on error.
59static const clang::driver::ArgStringList *getCC1Arguments(
60    clang::DiagnosticsEngine *Diagnostics,
61    clang::driver::Compilation *Compilation) {
62  // We expect to get back exactly one Command job, if we didn't something
63  // failed. Extract that job from the Compilation.
64  const clang::driver::JobList &Jobs = Compilation->getJobs();
65  if (Jobs.size() != 1 || !isa<clang::driver::Command>(*Jobs.begin())) {
66    llvm::SmallString<256> error_msg;
67    llvm::raw_svector_ostream error_stream(error_msg);
68    Compilation->PrintJob(error_stream, Compilation->getJobs(), "; ", true);
69    Diagnostics->Report(clang::diag::err_fe_expected_compiler_job)
70        << error_stream.str();
71    return NULL;
72  }
73
74  // The one job we find should be to invoke clang again.
75  const clang::driver::Command *Cmd =
76      cast<clang::driver::Command>(*Jobs.begin());
77  if (StringRef(Cmd->getCreator().getName()) != "clang") {
78    Diagnostics->Report(clang::diag::err_fe_expected_clang_command);
79    return NULL;
80  }
81
82  return &Cmd->getArguments();
83}
84
85/// \brief Returns a clang build invocation initialized from the CC1 flags.
86static clang::CompilerInvocation *newInvocation(
87    clang::DiagnosticsEngine *Diagnostics,
88    const clang::driver::ArgStringList &CC1Args) {
89  assert(!CC1Args.empty() && "Must at least contain the program name!");
90  clang::CompilerInvocation *Invocation = new clang::CompilerInvocation;
91  clang::CompilerInvocation::CreateFromArgs(
92      *Invocation, CC1Args.data() + 1, CC1Args.data() + CC1Args.size(),
93      *Diagnostics);
94  Invocation->getFrontendOpts().DisableFree = false;
95  return Invocation;
96}
97
98bool runToolOnCode(clang::FrontendAction *ToolAction, const Twine &Code,
99                   const Twine &FileName) {
100  return runToolOnCodeWithArgs(
101      ToolAction, Code, std::vector<std::string>(), FileName);
102}
103
104bool runToolOnCodeWithArgs(clang::FrontendAction *ToolAction, const Twine &Code,
105                           const std::vector<std::string> &Args,
106                           const Twine &FileName) {
107  SmallString<16> FileNameStorage;
108  StringRef FileNameRef = FileName.toNullTerminatedStringRef(FileNameStorage);
109  std::vector<std::string> Commands;
110  Commands.push_back("clang-tool");
111  Commands.push_back("-fsyntax-only");
112  Commands.insert(Commands.end(), Args.begin(), Args.end());
113  Commands.push_back(FileNameRef.data());
114  FileManager Files((FileSystemOptions()));
115  ToolInvocation Invocation(Commands, ToolAction, &Files);
116
117  SmallString<1024> CodeStorage;
118  Invocation.mapVirtualFile(FileNameRef,
119                            Code.toNullTerminatedStringRef(CodeStorage));
120  return Invocation.run();
121}
122
123std::string getAbsolutePath(StringRef File) {
124  llvm::SmallString<1024> BaseDirectory;
125  if (const char *PWD = ::getenv("PWD"))
126    BaseDirectory = PWD;
127  else
128    llvm::sys::fs::current_path(BaseDirectory);
129  SmallString<1024> PathStorage;
130  if (llvm::sys::path::is_absolute(File)) {
131    llvm::sys::path::native(File, PathStorage);
132    return PathStorage.str();
133  }
134  StringRef RelativePath(File);
135  // FIXME: Should '.\\' be accepted on Win32?
136  if (RelativePath.startswith("./")) {
137    RelativePath = RelativePath.substr(strlen("./"));
138  }
139  llvm::SmallString<1024> AbsolutePath(BaseDirectory);
140  llvm::sys::path::append(AbsolutePath, RelativePath);
141  llvm::sys::path::native(Twine(AbsolutePath), PathStorage);
142  return PathStorage.str();
143}
144
145ToolInvocation::ToolInvocation(
146    ArrayRef<std::string> CommandLine, FrontendAction *ToolAction,
147    FileManager *Files)
148    : CommandLine(CommandLine.vec()), ToolAction(ToolAction), Files(Files) {
149}
150
151void ToolInvocation::mapVirtualFile(StringRef FilePath, StringRef Content) {
152  SmallString<1024> PathStorage;
153  llvm::sys::path::native(FilePath, PathStorage);
154  MappedFileContents[PathStorage] = Content;
155}
156
157bool ToolInvocation::run() {
158  std::vector<const char*> Argv;
159  for (int I = 0, E = CommandLine.size(); I != E; ++I)
160    Argv.push_back(CommandLine[I].c_str());
161  const char *const BinaryName = Argv[0];
162  DiagnosticOptions DefaultDiagnosticOptions;
163  TextDiagnosticPrinter DiagnosticPrinter(
164      llvm::errs(), DefaultDiagnosticOptions);
165  DiagnosticsEngine Diagnostics(llvm::IntrusiveRefCntPtr<clang::DiagnosticIDs>(
166      new DiagnosticIDs()), &DiagnosticPrinter, false);
167
168  const llvm::OwningPtr<clang::driver::Driver> Driver(
169      newDriver(&Diagnostics, BinaryName));
170  // Since the input might only be virtual, don't check whether it exists.
171  Driver->setCheckInputsExist(false);
172  const llvm::OwningPtr<clang::driver::Compilation> Compilation(
173      Driver->BuildCompilation(llvm::makeArrayRef(Argv)));
174  const clang::driver::ArgStringList *const CC1Args = getCC1Arguments(
175      &Diagnostics, Compilation.get());
176  if (CC1Args == NULL) {
177    return false;
178  }
179  llvm::OwningPtr<clang::CompilerInvocation> Invocation(
180      newInvocation(&Diagnostics, *CC1Args));
181  return runInvocation(BinaryName, Compilation.get(), Invocation.take(),
182                       *CC1Args);
183}
184
185bool ToolInvocation::runInvocation(
186    const char *BinaryName,
187    clang::driver::Compilation *Compilation,
188    clang::CompilerInvocation *Invocation,
189    const clang::driver::ArgStringList &CC1Args) {
190  // Show the invocation, with -v.
191  if (Invocation->getHeaderSearchOpts().Verbose) {
192    llvm::errs() << "clang Invocation:\n";
193    Compilation->PrintJob(llvm::errs(), Compilation->getJobs(), "\n", true);
194    llvm::errs() << "\n";
195  }
196
197  // Create a compiler instance to handle the actual work.
198  clang::CompilerInstance Compiler;
199  Compiler.setInvocation(Invocation);
200  Compiler.setFileManager(Files);
201  // FIXME: What about LangOpts?
202
203  // ToolAction can have lifetime requirements for Compiler or its members, and
204  // we need to ensure it's deleted earlier than Compiler. So we pass it to an
205  // OwningPtr declared after the Compiler variable.
206  llvm::OwningPtr<FrontendAction> ScopedToolAction(ToolAction.take());
207
208  // Create the compilers actual diagnostics engine.
209  Compiler.createDiagnostics(CC1Args.size(),
210                             const_cast<char**>(CC1Args.data()));
211  if (!Compiler.hasDiagnostics())
212    return false;
213
214  Compiler.createSourceManager(*Files);
215  addFileMappingsTo(Compiler.getSourceManager());
216
217  const bool Success = Compiler.ExecuteAction(*ScopedToolAction);
218
219  Compiler.resetAndLeakFileManager();
220  Files->clearStatCaches();
221  return Success;
222}
223
224void ToolInvocation::addFileMappingsTo(SourceManager &Sources) {
225  for (llvm::StringMap<StringRef>::const_iterator
226           It = MappedFileContents.begin(), End = MappedFileContents.end();
227       It != End; ++It) {
228    // Inject the code as the given file name into the preprocessor options.
229    const llvm::MemoryBuffer *Input =
230        llvm::MemoryBuffer::getMemBuffer(It->getValue());
231    // FIXME: figure out what '0' stands for.
232    const FileEntry *FromFile = Files->getVirtualFile(
233        It->getKey(), Input->getBufferSize(), 0);
234    Sources.overrideFileContents(FromFile, Input);
235  }
236}
237
238ClangTool::ClangTool(const CompilationDatabase &Compilations,
239                     ArrayRef<std::string> SourcePaths)
240    : Files((FileSystemOptions())),
241      ArgsAdjuster(new ClangSyntaxOnlyAdjuster()) {
242  for (unsigned I = 0, E = SourcePaths.size(); I != E; ++I) {
243    llvm::SmallString<1024> File(getAbsolutePath(SourcePaths[I]));
244
245    std::vector<CompileCommand> CompileCommandsForFile =
246      Compilations.getCompileCommands(File.str());
247    if (!CompileCommandsForFile.empty()) {
248      for (int I = 0, E = CompileCommandsForFile.size(); I != E; ++I) {
249        CompileCommands.push_back(std::make_pair(File.str(),
250                                  CompileCommandsForFile[I]));
251      }
252    } else {
253      // FIXME: There are two use cases here: doing a fuzzy
254      // "find . -name '*.cc' |xargs tool" match, where as a user I don't care
255      // about the .cc files that were not found, and the use case where I
256      // specify all files I want to run over explicitly, where this should
257      // be an error. We'll want to add an option for this.
258      llvm::outs() << "Skipping " << File << ". Command line not found.\n";
259    }
260  }
261}
262
263void ClangTool::mapVirtualFile(StringRef FilePath, StringRef Content) {
264  MappedFileContents.push_back(std::make_pair(FilePath, Content));
265}
266
267void ClangTool::setArgumentsAdjuster(ArgumentsAdjuster *Adjuster) {
268  ArgsAdjuster.reset(Adjuster);
269}
270
271int ClangTool::run(FrontendActionFactory *ActionFactory) {
272  // Exists solely for the purpose of lookup of the resource path.
273  // This just needs to be some symbol in the binary.
274  static int StaticSymbol;
275  // The driver detects the builtin header path based on the path of the
276  // executable.
277  // FIXME: On linux, GetMainExecutable is independent of the value of the
278  // first argument, thus allowing ClangTool and runToolOnCode to just
279  // pass in made-up names here. Make sure this works on other platforms.
280  std::string MainExecutable =
281    llvm::sys::Path::GetMainExecutable("clang_tool", &StaticSymbol).str();
282
283  bool ProcessingFailed = false;
284  for (unsigned I = 0; I < CompileCommands.size(); ++I) {
285    std::string File = CompileCommands[I].first;
286    // FIXME: chdir is thread hostile; on the other hand, creating the same
287    // behavior as chdir is complex: chdir resolves the path once, thus
288    // guaranteeing that all subsequent relative path operations work
289    // on the same path the original chdir resulted in. This makes a difference
290    // for example on network filesystems, where symlinks might be switched
291    // during runtime of the tool. Fixing this depends on having a file system
292    // abstraction that allows openat() style interactions.
293    if (chdir(CompileCommands[I].second.Directory.c_str()))
294      llvm::report_fatal_error("Cannot chdir into \"" +
295                               CompileCommands[I].second.Directory + "\n!");
296    std::vector<std::string> CommandLine =
297      ArgsAdjuster->Adjust(CompileCommands[I].second.CommandLine);
298    assert(!CommandLine.empty());
299    CommandLine[0] = MainExecutable;
300    llvm::outs() << "Processing: " << File << ".\n";
301    ToolInvocation Invocation(CommandLine, ActionFactory->create(), &Files);
302    for (int I = 0, E = MappedFileContents.size(); I != E; ++I) {
303      Invocation.mapVirtualFile(MappedFileContents[I].first,
304                                MappedFileContents[I].second);
305    }
306    if (!Invocation.run()) {
307      llvm::outs() << "Error while processing " << File << ".\n";
308      ProcessingFailed = true;
309    }
310  }
311  return ProcessingFailed ? 1 : 0;
312}
313
314} // end namespace tooling
315} // end namespace clang
316