clang/lib/Tooling/CommonOptionsParser.cpp

   1 //===--- CommonOptionsParser.cpp - common options for clang tools ---------===//
   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 the CommonOptionsParser class used to parse common
  10 //  command-line options for clang tools, so that they can be run as separate
  11 //  command-line applications with a consistent common interface for handling
  12 //  compilation database and input files.
  13 //
  14 //  It provides a common subset of command-line options, common algorithm
  15 //  for locating a compilation database and source files, and help messages
  16 //  for the basic command-line interface.
  17 //
  18 //  It creates a CompilationDatabase and reads common command-line options.
  19 //
  20 //  This class uses the Clang Tooling infrastructure, see
  21 //    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
  22 //  for details on setting it up with LLVM source tree.
  23 //
  24 //===----------------------------------------------------------------------===//
  25
  26 #include "clang/Tooling/CommonOptionsParser.h"
  27 #include "clang/Tooling/Tooling.h"
  28 #include "llvm/Support/CommandLine.h"
  29
  30 using namespace clang::tooling;
  31 using namespace llvm;
  32
  33 const char *const CommonOptionsParser::HelpMessage =
  34     "\n"
  35     "-p <build-path> is used to read a compile command database.\n"
  36     "\n"
  37     "\tFor example, it can be a CMake build directory in which a file named\n"
  38     "\tcompile_commands.json exists (use -DCMAKE_EXPORT_COMPILE_COMMANDS=ON\n"
  39     "\tCMake option to get this output). When no build path is specified,\n"
  40     "\ta search for compile_commands.json will be attempted through all\n"
  41     "\tparent paths of the first input file . See:\n"
  42     "\thttps://clang.llvm.org/docs/HowToSetupToolingForLLVM.html for an\n"
  43     "\texample of setting up Clang Tooling on a source tree.\n"
  44     "\n"
  45     "<source0> ... specify the paths of source files. These paths are\n"
  46     "\tlooked up in the compile command database. If the path of a file is\n"
  47     "\tabsolute, it needs to point into CMake's source tree. If the path is\n"
  48     "\trelative, the current working directory needs to be in the CMake\n"
  49     "\tsource tree and the file must be in a subdirectory of the current\n"
  50     "\tworking directory. \"./\" prefixes in the relative files will be\n"
  51     "\tautomatically removed, but the rest of a relative path must be a\n"
  52     "\tsuffix of a path in the compile command database.\n"
  53     "\n";
  54
  55 void ArgumentsAdjustingCompilations::appendArgumentsAdjuster(
  56     ArgumentsAdjuster Adjuster) {
  57   Adjusters.push_back(std::move(Adjuster));
  58 }
  59
  60 std::vector<CompileCommand> ArgumentsAdjustingCompilations::getCompileCommands(
  61     StringRef FilePath) const {
  62   return adjustCommands(Compilations->getCompileCommands(FilePath));
  63 }
  64
  65 std::vector<std::string>
  66 ArgumentsAdjustingCompilations::getAllFiles() const {
  67   return Compilations->getAllFiles();
  68 }
  69
  70 std::vector<CompileCommand>
  71 ArgumentsAdjustingCompilations::getAllCompileCommands() const {
  72   return adjustCommands(Compilations->getAllCompileCommands());
  73 }
  74
  75 std::vector<CompileCommand> ArgumentsAdjustingCompilations::adjustCommands(
  76     std::vector<CompileCommand> Commands) const {
  77   for (CompileCommand &Command : Commands)
  78     for (const auto &Adjuster : Adjusters)
  79       Command.CommandLine = Adjuster(Command.CommandLine, Command.Filename);
  80   return Commands;
  81 }
  82
  83 llvm::Error CommonOptionsParser::init(
  84     int &argc, const char **argv, cl::OptionCategory &Category,
  85     llvm::cl::NumOccurrencesFlag OccurrencesFlag, const char *Overview) {
  86
  87   static cl::opt<std::string> BuildPath("p", cl::desc("Build path"),
  88                                         cl::Optional, cl::cat(Category),
  89                                         cl::sub(cl::SubCommand::getAll()));
  90
  91   static cl::list<std::string> SourcePaths(
  92       cl::Positional, cl::desc("<source0> [... <sourceN>]"), OccurrencesFlag,
  93       cl::cat(Category), cl::sub(cl::SubCommand::getAll()));
  94
  95   static cl::list<std::string> ArgsAfter(
  96       "extra-arg",
  97       cl::desc("Additional argument to append to the compiler command line"),
  98       cl::cat(Category), cl::sub(cl::SubCommand::getAll()));
  99
 100   static cl::list<std::string> ArgsBefore(
 101       "extra-arg-before",
 102       cl::desc("Additional argument to prepend to the compiler command line"),
 103       cl::cat(Category), cl::sub(cl::SubCommand::getAll()));
 104
 105   cl::ResetAllOptionOccurrences();
 106
 107   cl::HideUnrelatedOptions(Category);
 108
 109   std::string ErrorMessage;
 110   Compilations =
 111       FixedCompilationDatabase::loadFromCommandLine(argc, argv, ErrorMessage);
 112   if (!ErrorMessage.empty())
 113     ErrorMessage.append("\n");
 114   llvm::raw_string_ostream OS(ErrorMessage);
 115   // Stop initializing if command-line option parsing failed.
 116   if (!cl::ParseCommandLineOptions(argc, argv, Overview, &OS)) {
 117     return llvm::make_error<llvm::StringError>(ErrorMessage,
 118                                                llvm::inconvertibleErrorCode());
 119   }
 120
 121   cl::PrintOptionValues();
 122
 123   SourcePathList = SourcePaths;
 124   if ((OccurrencesFlag == cl::ZeroOrMore || OccurrencesFlag == cl::Optional) &&
 125       SourcePathList.empty())
 126     return llvm::Error::success();
 127   if (!Compilations) {
 128     if (!BuildPath.empty()) {
 129       Compilations =
 130           CompilationDatabase::autoDetectFromDirectory(BuildPath, ErrorMessage);
 131     } else {
 132       Compilations = CompilationDatabase::autoDetectFromSource(SourcePaths[0],
 133                                                                ErrorMessage);
 134     }
 135     if (!Compilations) {
 136       llvm::errs() << "Error while trying to load a compilation database:\n"
 137                    << ErrorMessage << "Running without flags.\n";
 138       Compilations.reset(
 139           new FixedCompilationDatabase(".", std::vector<std::string>()));
 140     }
 141   }
 142   auto AdjustingCompilations =
 143       std::make_unique<ArgumentsAdjustingCompilations>(
 144           std::move(Compilations));
 145   Adjuster =
 146       getInsertArgumentAdjuster(ArgsBefore, ArgumentInsertPosition::BEGIN);
 147   Adjuster = combineAdjusters(
 148       std::move(Adjuster),
 149       getInsertArgumentAdjuster(ArgsAfter, ArgumentInsertPosition::END));
 150   AdjustingCompilations->appendArgumentsAdjuster(Adjuster);
 151   Compilations = std::move(AdjustingCompilations);
 152   return llvm::Error::success();
 153 }
 154
 155 llvm::Expected<CommonOptionsParser> CommonOptionsParser::create(
 156     int &argc, const char **argv, llvm::cl::OptionCategory &Category,
 157     llvm::cl::NumOccurrencesFlag OccurrencesFlag, const char *Overview) {
 158   CommonOptionsParser Parser;
 159   llvm::Error Err =
 160       Parser.init(argc, argv, Category, OccurrencesFlag, Overview);
 161   if (Err)
 162     return std::move(Err);
 163   return std::move(Parser);
 164 }
 165
 166 CommonOptionsParser::CommonOptionsParser(
 167     int &argc, const char **argv, cl::OptionCategory &Category,
 168     llvm::cl::NumOccurrencesFlag OccurrencesFlag, const char *Overview) {
 169   llvm::Error Err = init(argc, argv, Category, OccurrencesFlag, Overview);
 170   if (Err) {
 171     llvm::report_fatal_error(
 172         Twine("CommonOptionsParser: failed to parse command-line arguments. ") +
 173         llvm::toString(std::move(Err)));
 174   }
 175 }