clang-tools-extra/clang-query/tool/ClangQuery.cpp

   1 //===---- ClangQuery.cpp - clang-query 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 tool is for interactive exploration of the Clang AST using AST matchers.
  10 // It currently allows the user to enter a matcher at an interactive prompt and
  11 // view the resulting bindings as diagnostics, AST pretty prints or AST dumps.
  12 // Example session:
  13 //
  14 // $ cat foo.c
  15 // void foo(void) {}
  16 // $ clang-query foo.c --
  17 // clang-query> match functionDecl()
  18 //
  19 // Match #1:
  20 //
  21 // foo.c:1:1: note: "root" binds here
  22 // void foo(void) {}
  23 // ^~~~~~~~~~~~~~~~~
  24 // 1 match.
  25 //
  26 //===----------------------------------------------------------------------===//
  27
  28 #include "Query.h"
  29 #include "QueryParser.h"
  30 #include "QuerySession.h"
  31 #include "clang/Frontend/ASTUnit.h"
  32 #include "clang/Tooling/CommonOptionsParser.h"
  33 #include "clang/Tooling/Tooling.h"
  34 #include "llvm/LineEditor/LineEditor.h"
  35 #include "llvm/Support/CommandLine.h"
  36 #include "llvm/Support/Error.h"
  37 #include "llvm/Support/MemoryBuffer.h"
  38 #include "llvm/Support/Signals.h"
  39 #include "llvm/Support/WithColor.h"
  40 #include <optional>
  41 #include <string>
  42
  43 using namespace clang;
  44 using namespace clang::ast_matchers;
  45 using namespace clang::ast_matchers::dynamic;
  46 using namespace clang::query;
  47 using namespace clang::tooling;
  48 using namespace llvm;
  49
  50 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
  51 static cl::OptionCategory ClangQueryCategory("clang-query options");
  52
  53 static cl::opt<bool>
  54     UseColor("use-color",
  55              cl::desc(
  56                  R"(Use colors in detailed AST output. If not set, colors
  57 will be used if the terminal connected to
  58 standard output supports colors.)"),
  59              cl::init(false), cl::cat(ClangQueryCategory));
  60
  61 static cl::list<std::string> Commands("c", cl::desc("Specify command to run"),
  62                                       cl::value_desc("command"),
  63                                       cl::cat(ClangQueryCategory));
  64
  65 static cl::list<std::string> CommandFiles("f",
  66                                           cl::desc("Read commands from file"),
  67                                           cl::value_desc("file"),
  68                                           cl::cat(ClangQueryCategory));
  69
  70 static cl::opt<std::string> PreloadFile(
  71     "preload",
  72     cl::desc("Preload commands from file and start interactive mode"),
  73     cl::value_desc("file"), cl::cat(ClangQueryCategory));
  74
  75 bool runCommandsInFile(const char *ExeName, std::string const &FileName,
  76                        QuerySession &QS) {
  77   FileQuery Query(FileName, ExeName);
  78   return !Query.run(llvm::errs(), QS);
  79 }
  80
  81 int main(int argc, const char **argv) {
  82   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
  83
  84   llvm::Expected<CommonOptionsParser> OptionsParser =
  85       CommonOptionsParser::create(argc, argv, ClangQueryCategory,
  86                                   llvm::cl::OneOrMore);
  87
  88   if (!OptionsParser) {
  89     llvm::WithColor::error() << llvm::toString(OptionsParser.takeError());
  90     return 1;
  91   }
  92
  93   if (!Commands.empty() && !CommandFiles.empty()) {
  94     llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
  95     return 1;
  96   }
  97
  98   if ((!Commands.empty() || !CommandFiles.empty()) && !PreloadFile.empty()) {
  99     llvm::errs() << argv[0]
 100                  << ": cannot specify both -c or -f with --preload\n";
 101     return 1;
 102   }
 103
 104   ClangTool Tool(OptionsParser->getCompilations(),
 105                  OptionsParser->getSourcePathList());
 106
 107   if (UseColor.getNumOccurrences() > 0) {
 108     ArgumentsAdjuster colorAdjustor = [](const CommandLineArguments &Args, StringRef /*unused*/) {
 109       CommandLineArguments AdjustedArgs = Args;
 110       if (UseColor)
 111         AdjustedArgs.push_back("-fdiagnostics-color");
 112       else
 113         AdjustedArgs.push_back("-fno-diagnostics-color");
 114       return AdjustedArgs;
 115     };
 116     Tool.appendArgumentsAdjuster(colorAdjustor);
 117   }
 118
 119   std::vector<std::unique_ptr<ASTUnit>> ASTs;
 120   int ASTStatus = 0;
 121   switch (Tool.buildASTs(ASTs)) {
 122   case 0:
 123     break;
 124   case 1: // Building ASTs failed.
 125     return 1;
 126   case 2:
 127     ASTStatus |= 1;
 128     llvm::errs() << "Failed to build AST for some of the files, "
 129                  << "results may be incomplete."
 130                  << "\n";
 131     break;
 132   default:
 133     llvm_unreachable("Unexpected status returned");
 134   }
 135
 136   QuerySession QS(ASTs);
 137
 138   if (!Commands.empty()) {
 139     for (auto &Command : Commands) {
 140       QueryRef Q = QueryParser::parse(Command, QS);
 141       if (!Q->run(llvm::outs(), QS))
 142         return 1;
 143     }
 144   } else if (!CommandFiles.empty()) {
 145     for (auto &CommandFile : CommandFiles) {
 146       if (runCommandsInFile(argv[0], CommandFile, QS))
 147         return 1;
 148     }
 149   } else {
 150     if (!PreloadFile.empty()) {
 151       if (runCommandsInFile(argv[0], PreloadFile, QS))
 152         return 1;
 153     }
 154     LineEditor LE("clang-query");
 155     LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
 156       return QueryParser::complete(Line, Pos, QS);
 157     });
 158     while (std::optional<std::string> Line = LE.readLine()) {
 159       QueryRef Q = QueryParser::parse(*Line, QS);
 160       Q->run(llvm::outs(), QS);
 161       llvm::outs().flush();
 162       if (QS.Terminate)
 163         break;
 164     }
 165   }
 166
 167   return ASTStatus;
 168 }