xref: /llvm-project/clang/tools/clang-check/ClangCheck.cpp (revision d64eccf4335e99360132b724d060d704892fbb02)
1 //===--- tools/clang-check/ClangCheck.cpp - Clang check tool --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file implements a clang-check tool that runs clang based on the info
10 //  stored in a compilation database.
11 //
12 //  This tool uses the Clang Tooling infrastructure, see
13 //    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
14 //  for details on setting it up with LLVM source tree.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "clang/AST/ASTConsumer.h"
19 #include "clang/Driver/Options.h"
20 #include "clang/Frontend/ASTConsumers.h"
21 #include "clang/Frontend/CompilerInstance.h"
22 #include "clang/Rewrite/Frontend/FixItRewriter.h"
23 #include "clang/Rewrite/Frontend/FrontendActions.h"
24 #include "clang/StaticAnalyzer/Frontend/FrontendActions.h"
25 #include "clang/Tooling/CommonOptionsParser.h"
26 #include "clang/Tooling/Syntax/BuildTree.h"
27 #include "clang/Tooling/Syntax/TokenBufferTokenManager.h"
28 #include "clang/Tooling/Syntax/Tokens.h"
29 #include "clang/Tooling/Syntax/Tree.h"
30 #include "clang/Tooling/Tooling.h"
31 #include "llvm/ADT/STLExtras.h"
32 #include "llvm/Option/OptTable.h"
33 #include "llvm/Support/Path.h"
34 #include "llvm/Support/Signals.h"
35 #include "llvm/Support/TargetSelect.h"
36 
37 using namespace clang::driver;
38 using namespace clang::tooling;
39 using namespace llvm;
40 
41 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
42 static cl::extrahelp MoreHelp(
43     "\tFor example, to run clang-check on all files in a subtree of the\n"
44     "\tsource tree, use:\n"
45     "\n"
46     "\t  find path/in/subtree -name '*.cpp'|xargs clang-check\n"
47     "\n"
48     "\tor using a specific build path:\n"
49     "\n"
50     "\t  find path/in/subtree -name '*.cpp'|xargs clang-check -p build/path\n"
51     "\n"
52     "\tNote, that path/in/subtree and current directory should follow the\n"
53     "\trules described above.\n"
54     "\n"
55 );
56 
57 static cl::OptionCategory ClangCheckCategory("clang-check options");
58 static const opt::OptTable &Options = getDriverOptTable();
59 static cl::opt<bool>
60     ASTDump("ast-dump",
61             cl::desc(Options.getOptionHelpText(options::OPT_ast_dump)),
62             cl::cat(ClangCheckCategory));
63 static cl::opt<bool>
64     ASTList("ast-list",
65             cl::desc(Options.getOptionHelpText(options::OPT_ast_list)),
66             cl::cat(ClangCheckCategory));
67 static cl::opt<bool>
68     ASTPrint("ast-print",
69              cl::desc(Options.getOptionHelpText(options::OPT_ast_print)),
70              cl::cat(ClangCheckCategory));
71 static cl::opt<std::string> ASTDumpFilter(
72     "ast-dump-filter",
73     cl::desc(Options.getOptionHelpText(options::OPT_ast_dump_filter)),
74     cl::cat(ClangCheckCategory));
75 static cl::opt<bool>
76     Analyze("analyze",
77             cl::desc(Options.getOptionHelpText(options::OPT_analyze)),
78             cl::cat(ClangCheckCategory));
79 static cl::opt<std::string>
80     AnalyzerOutput("analyzer-output-path",
81                    cl::desc(Options.getOptionHelpText(options::OPT_o)),
82                    cl::cat(ClangCheckCategory));
83 
84 static cl::opt<bool>
85     Fixit("fixit", cl::desc(Options.getOptionHelpText(options::OPT_fixit)),
86           cl::cat(ClangCheckCategory));
87 static cl::opt<bool> FixWhatYouCan(
88     "fix-what-you-can",
89     cl::desc(Options.getOptionHelpText(options::OPT_fix_what_you_can)),
90     cl::cat(ClangCheckCategory));
91 
92 static cl::opt<bool> SyntaxTreeDump("syntax-tree-dump",
93                                     cl::desc("dump the syntax tree"),
94                                     cl::cat(ClangCheckCategory));
95 static cl::opt<bool> TokensDump("tokens-dump",
96                                 cl::desc("dump the preprocessed tokens"),
97                                 cl::cat(ClangCheckCategory));
98 
99 namespace {
100 
101 // FIXME: Move FixItRewriteInPlace from lib/Rewrite/Frontend/FrontendActions.cpp
102 // into a header file and reuse that.
103 class FixItOptions : public clang::FixItOptions {
104 public:
105   FixItOptions() {
106     FixWhatYouCan = ::FixWhatYouCan;
107   }
108 
109   std::string RewriteFilename(const std::string& filename, int &fd) override {
110     // We don't need to do permission checking here since clang will diagnose
111     // any I/O errors itself.
112 
113     fd = -1;  // No file descriptor for file.
114 
115     return filename;
116   }
117 };
118 
119 /// Subclasses \c clang::FixItRewriter to not count fixed errors/warnings
120 /// in the final error counts.
121 ///
122 /// This has the side-effect that clang-check -fixit exits with code 0 on
123 /// successfully fixing all errors.
124 class FixItRewriter : public clang::FixItRewriter {
125 public:
126   FixItRewriter(clang::DiagnosticsEngine& Diags,
127                 clang::SourceManager& SourceMgr,
128                 const clang::LangOptions& LangOpts,
129                 clang::FixItOptions* FixItOpts)
130       : clang::FixItRewriter(Diags, SourceMgr, LangOpts, FixItOpts) {
131   }
132 
133   bool IncludeInDiagnosticCounts() const override { return false; }
134 };
135 
136 /// Subclasses \c clang::FixItAction so that we can install the custom
137 /// \c FixItRewriter.
138 class ClangCheckFixItAction : public clang::FixItAction {
139 public:
140   bool BeginSourceFileAction(clang::CompilerInstance& CI) override {
141     FixItOpts.reset(new FixItOptions);
142     Rewriter.reset(new FixItRewriter(CI.getDiagnostics(), CI.getSourceManager(),
143                                      CI.getLangOpts(), FixItOpts.get()));
144     return true;
145   }
146 };
147 
148 class DumpSyntaxTree : public clang::ASTFrontendAction {
149 public:
150   std::unique_ptr<clang::ASTConsumer>
151   CreateASTConsumer(clang::CompilerInstance &CI, StringRef InFile) override {
152     class Consumer : public clang::ASTConsumer {
153     public:
154       Consumer(clang::CompilerInstance &CI) : Collector(CI.getPreprocessor()) {}
155 
156       void HandleTranslationUnit(clang::ASTContext &AST) override {
157         clang::syntax::TokenBuffer TB = std::move(Collector).consume();
158         if (TokensDump)
159           llvm::outs() << TB.dumpForTests();
160         clang::syntax::TokenBufferTokenManager TBTM(TB, AST.getLangOpts(),
161                                                     AST.getSourceManager());
162         clang::syntax::Arena A;
163         llvm::outs()
164             << clang::syntax::buildSyntaxTree(A, TBTM, AST)->dump(TBTM);
165       }
166 
167     private:
168       clang::syntax::TokenCollector Collector;
169     };
170     return std::make_unique<Consumer>(CI);
171   }
172 };
173 
174 class ClangCheckActionFactory {
175 public:
176   std::unique_ptr<clang::ASTConsumer> newASTConsumer() {
177     if (ASTList)
178       return clang::CreateASTDeclNodeLister();
179     if (ASTDump)
180       return clang::CreateASTDumper(nullptr /*Dump to stdout.*/, ASTDumpFilter,
181                                     /*DumpDecls=*/true,
182                                     /*Deserialize=*/false,
183                                     /*DumpLookups=*/false,
184                                     /*DumpDeclTypes=*/false,
185                                     clang::ADOF_Default);
186     if (ASTPrint)
187       return clang::CreateASTPrinter(nullptr, ASTDumpFilter);
188     return std::make_unique<clang::ASTConsumer>();
189   }
190 };
191 
192 } // namespace
193 
194 int main(int argc, const char **argv) {
195   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
196 
197   // Initialize targets for clang module support.
198   llvm::InitializeAllTargets();
199   llvm::InitializeAllTargetMCs();
200   llvm::InitializeAllAsmPrinters();
201   llvm::InitializeAllAsmParsers();
202 
203   auto ExpectedParser =
204       CommonOptionsParser::create(argc, argv, ClangCheckCategory);
205   if (!ExpectedParser) {
206     llvm::errs() << ExpectedParser.takeError();
207     return 1;
208   }
209   CommonOptionsParser &OptionsParser = ExpectedParser.get();
210   ClangTool Tool(OptionsParser.getCompilations(),
211                  OptionsParser.getSourcePathList());
212 
213   if (Analyze) {
214     // Set output path if is provided by user.
215     //
216     // As the original -o options have been removed by default via the
217     // strip-output adjuster, we only need to add the analyzer -o options here
218     // when it is provided by users.
219     if (!AnalyzerOutput.empty())
220       Tool.appendArgumentsAdjuster(
221           getInsertArgumentAdjuster(CommandLineArguments{"-o", AnalyzerOutput},
222                                     ArgumentInsertPosition::END));
223 
224     // Running the analyzer requires --analyze. Other modes can work with the
225     // -fsyntax-only option.
226     //
227     // The syntax-only adjuster is installed by default.
228     // Good: It also strips options that trigger extra output, like -save-temps.
229     // Bad:  We don't want the -fsyntax-only when executing the static analyzer.
230     //
231     // To enable the static analyzer, we first strip all -fsyntax-only options
232     // and then add an --analyze option to the front.
233     Tool.appendArgumentsAdjuster(
234         [&](const CommandLineArguments &Args, StringRef /*unused*/) {
235           CommandLineArguments AdjustedArgs;
236           for (const std::string &Arg : Args)
237             if (Arg != "-fsyntax-only")
238               AdjustedArgs.emplace_back(Arg);
239           return AdjustedArgs;
240         });
241     Tool.appendArgumentsAdjuster(
242         getInsertArgumentAdjuster("--analyze", ArgumentInsertPosition::BEGIN));
243   }
244 
245   ClangCheckActionFactory CheckFactory;
246   std::unique_ptr<FrontendActionFactory> FrontendFactory;
247 
248   // Choose the correct factory based on the selected mode.
249   if (Analyze)
250     FrontendFactory = newFrontendActionFactory<clang::ento::AnalysisAction>();
251   else if (Fixit)
252     FrontendFactory = newFrontendActionFactory<ClangCheckFixItAction>();
253   else if (SyntaxTreeDump || TokensDump)
254     FrontendFactory = newFrontendActionFactory<DumpSyntaxTree>();
255   else
256     FrontendFactory = newFrontendActionFactory(&CheckFactory);
257 
258   return Tool.run(FrontendFactory.get());
259 }
260