1 //===--- tools/pp-trace/PPTrace.cpp - Clang preprocessor tracer -----------===// 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 pp-trace, a tool for displaying a textual trace 11 // of the Clang preprocessor activity. It's based on a derivation of the 12 // PPCallbacks class, that once registerd with Clang, receives callback calls 13 // to its virtual members, and outputs the information passed to the callbacks 14 // in a high-level YAML format. 15 // 16 // The pp-trace tool also serves as the basis for a test of the PPCallbacks 17 // mechanism. 18 // 19 // The pp-trace tool supports the following general command line format: 20 // 21 // pp-trace [pp-trace options] (source file) [compiler options] 22 // 23 // Basically you put the pp-trace options first, then the source file or files, 24 // and then any options you want to pass to the compiler. 25 // 26 // These are the pp-trace options: 27 // 28 // -ignore (callback list) Don't display output for a comma-separated 29 // list of callbacks, i.e.: 30 // -ignore "FileChanged,InclusionDirective" 31 // 32 // -output (file) Output trace to the given file in a YAML 33 // format, e.g.: 34 // 35 // --- 36 // - Callback: Name 37 // Argument1: Value1 38 // Argument2: Value2 39 // (etc.) 40 // ... 41 // 42 // Future Directions: 43 // 44 // 1. Add option opposite to "-ignore" that specifys a comma-separated option 45 // list of callbacs. Perhaps "-only" or "-exclusive". 46 // 47 //===----------------------------------------------------------------------===// 48 49 #include "PPCallbacksTracker.h" 50 #include "clang/AST/ASTConsumer.h" 51 #include "clang/AST/ASTContext.h" 52 #include "clang/AST/RecursiveASTVisitor.h" 53 #include "clang/Basic/SourceManager.h" 54 #include "clang/Driver/Options.h" 55 #include "clang/Frontend/CompilerInstance.h" 56 #include "clang/Frontend/FrontendActions.h" 57 #include "clang/Lex/Preprocessor.h" 58 #include "clang/Tooling/CompilationDatabase.h" 59 #include "clang/Tooling/Tooling.h" 60 #include "llvm/Option/Arg.h" 61 #include "llvm/Option/ArgList.h" 62 #include "llvm/Option/OptTable.h" 63 #include "llvm/Option/Option.h" 64 #include "llvm/Support/CommandLine.h" 65 #include "llvm/Support/FileSystem.h" 66 #include "llvm/Support/MemoryBuffer.h" 67 #include "llvm/Support/Path.h" 68 #include "llvm/Support/ToolOutputFile.h" 69 #include <algorithm> 70 #include <fstream> 71 #include <iterator> 72 #include <string> 73 #include <vector> 74 75 using namespace clang; 76 using namespace clang::driver; 77 using namespace clang::driver::options; 78 using namespace clang::tooling; 79 using namespace llvm; 80 using namespace llvm::opt; 81 82 // Options: 83 84 // Collect the source files. 85 cl::list<std::string> SourcePaths(cl::Positional, 86 cl::desc("<source0> [... <sourceN>]"), 87 cl::OneOrMore); 88 89 // Option to specify a list or one or more callback names to ignore. 90 cl::opt<std::string> IgnoreCallbacks( 91 "ignore", cl::init(""), 92 cl::desc("Ignore callbacks, i.e. \"Callback1, Callback2...\".")); 93 94 // Option to specify the trace output file name. 95 cl::opt<std::string> OutputFileName( 96 "output", cl::init(""), 97 cl::desc("Output trace to the given file name or '-' for stdout.")); 98 99 // Collect all other arguments, which will be passed to the front end. 100 cl::list<std::string> 101 CC1Arguments(cl::ConsumeAfter, 102 cl::desc("<arguments to be passed to front end>...")); 103 104 // Frontend action stuff: 105 106 // Consumer is responsible for setting up the callbacks. 107 class PPTraceConsumer : public ASTConsumer { 108 public: 109 PPTraceConsumer(SmallSet<std::string, 4> &Ignore, 110 std::vector<CallbackCall> &CallbackCalls, Preprocessor &PP) { 111 // PP takes ownership. 112 PP.addPPCallbacks(llvm::make_unique<PPCallbacksTracker>(Ignore, 113 CallbackCalls, PP)); 114 } 115 }; 116 117 class PPTraceAction : public SyntaxOnlyAction { 118 public: 119 PPTraceAction(SmallSet<std::string, 4> &Ignore, 120 std::vector<CallbackCall> &CallbackCalls) 121 : Ignore(Ignore), CallbackCalls(CallbackCalls) {} 122 123 protected: 124 std::unique_ptr<clang::ASTConsumer> 125 CreateASTConsumer(CompilerInstance &CI, StringRef InFile) override { 126 return llvm::make_unique<PPTraceConsumer>(Ignore, CallbackCalls, 127 CI.getPreprocessor()); 128 } 129 130 private: 131 SmallSet<std::string, 4> &Ignore; 132 std::vector<CallbackCall> &CallbackCalls; 133 }; 134 135 class PPTraceFrontendActionFactory : public FrontendActionFactory { 136 public: 137 PPTraceFrontendActionFactory(SmallSet<std::string, 4> &Ignore, 138 std::vector<CallbackCall> &CallbackCalls) 139 : Ignore(Ignore), CallbackCalls(CallbackCalls) {} 140 141 virtual PPTraceAction *create() { 142 return new PPTraceAction(Ignore, CallbackCalls); 143 } 144 145 private: 146 SmallSet<std::string, 4> &Ignore; 147 std::vector<CallbackCall> &CallbackCalls; 148 }; 149 150 // Output the trace given its data structure and a stream. 151 int outputPPTrace(std::vector<CallbackCall> &CallbackCalls, 152 llvm::raw_ostream &OS) { 153 // Mark start of document. 154 OS << "---\n"; 155 156 for (std::vector<CallbackCall>::const_iterator I = CallbackCalls.begin(), 157 E = CallbackCalls.end(); 158 I != E; ++I) { 159 const CallbackCall &Callback = *I; 160 OS << "- Callback: " << Callback.Name << "\n"; 161 162 for (std::vector<Argument>::const_iterator AI = Callback.Arguments.begin(), 163 AE = Callback.Arguments.end(); 164 AI != AE; ++AI) { 165 const Argument &Arg = *AI; 166 OS << " " << Arg.Name << ": " << Arg.Value << "\n"; 167 } 168 } 169 170 // Mark end of document. 171 OS << "...\n"; 172 173 return 0; 174 } 175 176 // Program entry point. 177 int main(int Argc, const char **Argv) { 178 179 // Parse command line. 180 cl::ParseCommandLineOptions(Argc, Argv, "pp-trace.\n"); 181 182 // Parse the IgnoreCallbacks list into strings. 183 SmallVector<StringRef, 32> IgnoreCallbacksStrings; 184 StringRef(IgnoreCallbacks).split(IgnoreCallbacksStrings, ",", 185 /*MaxSplit=*/ -1, /*KeepEmpty=*/false); 186 SmallSet<std::string, 4> Ignore; 187 for (SmallVector<StringRef, 32>::iterator I = IgnoreCallbacksStrings.begin(), 188 E = IgnoreCallbacksStrings.end(); 189 I != E; ++I) 190 Ignore.insert(*I); 191 192 // Create the compilation database. 193 SmallString<256> PathBuf; 194 sys::fs::current_path(PathBuf); 195 std::unique_ptr<CompilationDatabase> Compilations; 196 Compilations.reset( 197 new FixedCompilationDatabase(Twine(PathBuf), CC1Arguments)); 198 199 // Store the callback trace information here. 200 std::vector<CallbackCall> CallbackCalls; 201 202 // Create the tool and run the compilation. 203 ClangTool Tool(*Compilations, SourcePaths); 204 PPTraceFrontendActionFactory Factory(Ignore, CallbackCalls); 205 int HadErrors = Tool.run(&Factory); 206 207 // If we had errors, exit early. 208 if (HadErrors) 209 return HadErrors; 210 211 // Do the output. 212 if (!OutputFileName.size()) { 213 HadErrors = outputPPTrace(CallbackCalls, llvm::outs()); 214 } else { 215 // Set up output file. 216 std::error_code EC; 217 llvm::tool_output_file Out(OutputFileName, EC, llvm::sys::fs::F_Text); 218 if (EC) { 219 llvm::errs() << "pp-trace: error creating " << OutputFileName << ":" 220 << EC.message() << "\n"; 221 return 1; 222 } 223 224 HadErrors = outputPPTrace(CallbackCalls, Out.os()); 225 226 // Tell tool_output_file that we want to keep the file. 227 if (HadErrors == 0) 228 Out.keep(); 229 } 230 231 return HadErrors; 232 } 233