clang  5.0.0
CommonOptionsParser.cpp
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1 //===--- CommonOptionsParser.cpp - common options for clang 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 the CommonOptionsParser class used to parse common
11 // command-line options for clang tools, so that they can be run as separate
12 // command-line applications with a consistent common interface for handling
13 // compilation database and input files.
14 //
15 // It provides a common subset of command-line options, common algorithm
16 // for locating a compilation database and source files, and help messages
17 // for the basic command-line interface.
18 //
19 // It creates a CompilationDatabase and reads common command-line options.
20 //
21 // This class uses the Clang Tooling infrastructure, see
22 // http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
23 // for details on setting it up with LLVM source tree.
24 //
25 //===----------------------------------------------------------------------===//
26 
27 #include "llvm/Support/CommandLine.h"
30 #include "clang/Tooling/Tooling.h"
31 
32 using namespace clang::tooling;
33 using namespace llvm;
34 
35 const char *const CommonOptionsParser::HelpMessage =
36  "\n"
37  "-p <build-path> is used to read a compile command database.\n"
38  "\n"
39  "\tFor example, it can be a CMake build directory in which a file named\n"
40  "\tcompile_commands.json exists (use -DCMAKE_EXPORT_COMPILE_COMMANDS=ON\n"
41  "\tCMake option to get this output). When no build path is specified,\n"
42  "\ta search for compile_commands.json will be attempted through all\n"
43  "\tparent paths of the first input file . See:\n"
44  "\thttp://clang.llvm.org/docs/HowToSetupToolingForLLVM.html for an\n"
45  "\texample of setting up Clang Tooling on a source tree.\n"
46  "\n"
47  "<source0> ... specify the paths of source files. These paths are\n"
48  "\tlooked up in the compile command database. If the path of a file is\n"
49  "\tabsolute, it needs to point into CMake's source tree. If the path is\n"
50  "\trelative, the current working directory needs to be in the CMake\n"
51  "\tsource tree and the file must be in a subdirectory of the current\n"
52  "\tworking directory. \"./\" prefixes in the relative files will be\n"
53  "\tautomatically removed, but the rest of a relative path must be a\n"
54  "\tsuffix of a path in the compile command database.\n"
55  "\n";
56 
57 namespace {
58 class ArgumentsAdjustingCompilations : public CompilationDatabase {
59 public:
60  ArgumentsAdjustingCompilations(
61  std::unique_ptr<CompilationDatabase> Compilations)
62  : Compilations(std::move(Compilations)) {}
63 
64  void appendArgumentsAdjuster(ArgumentsAdjuster Adjuster) {
65  Adjusters.push_back(std::move(Adjuster));
66  }
67 
68  std::vector<CompileCommand>
69  getCompileCommands(StringRef FilePath) const override {
70  return adjustCommands(Compilations->getCompileCommands(FilePath));
71  }
72 
73  std::vector<std::string> getAllFiles() const override {
74  return Compilations->getAllFiles();
75  }
76 
77  std::vector<CompileCommand> getAllCompileCommands() const override {
78  return adjustCommands(Compilations->getAllCompileCommands());
79  }
80 
81 private:
82  std::unique_ptr<CompilationDatabase> Compilations;
83  std::vector<ArgumentsAdjuster> Adjusters;
84 
85  std::vector<CompileCommand>
86  adjustCommands(std::vector<CompileCommand> Commands) const {
87  for (CompileCommand &Command : Commands)
88  for (const auto &Adjuster : Adjusters)
89  Command.CommandLine = Adjuster(Command.CommandLine, Command.Filename);
90  return Commands;
91  }
92 };
93 } // namespace
94 
96  int &argc, const char **argv, cl::OptionCategory &Category,
97  llvm::cl::NumOccurrencesFlag OccurrencesFlag, const char *Overview) {
98  static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
99 
100  static cl::opt<std::string> BuildPath("p", cl::desc("Build path"),
101  cl::Optional, cl::cat(Category));
102 
103  static cl::list<std::string> SourcePaths(
104  cl::Positional, cl::desc("<source0> [... <sourceN>]"), OccurrencesFlag,
105  cl::cat(Category));
106 
107  static cl::list<std::string> ArgsAfter(
108  "extra-arg",
109  cl::desc("Additional argument to append to the compiler command line"),
110  cl::cat(Category));
111 
112  static cl::list<std::string> ArgsBefore(
113  "extra-arg-before",
114  cl::desc("Additional argument to prepend to the compiler command line"),
115  cl::cat(Category));
116 
117  cl::HideUnrelatedOptions(Category);
118 
119  std::string ErrorMessage;
120  Compilations =
121  FixedCompilationDatabase::loadFromCommandLine(argc, argv, ErrorMessage);
122  if (!Compilations && !ErrorMessage.empty())
123  llvm::errs() << ErrorMessage;
124  cl::ParseCommandLineOptions(argc, argv, Overview);
125  cl::PrintOptionValues();
126 
127  SourcePathList = SourcePaths;
128  if ((OccurrencesFlag == cl::ZeroOrMore || OccurrencesFlag == cl::Optional) &&
129  SourcePathList.empty())
130  return;
131  if (!Compilations) {
132  if (!BuildPath.empty()) {
133  Compilations =
134  CompilationDatabase::autoDetectFromDirectory(BuildPath, ErrorMessage);
135  } else {
136  Compilations = CompilationDatabase::autoDetectFromSource(SourcePaths[0],
137  ErrorMessage);
138  }
139  if (!Compilations) {
140  llvm::errs() << "Error while trying to load a compilation database:\n"
141  << ErrorMessage << "Running without flags.\n";
142  Compilations.reset(
143  new FixedCompilationDatabase(".", std::vector<std::string>()));
144  }
145  }
146  auto AdjustingCompilations =
147  llvm::make_unique<ArgumentsAdjustingCompilations>(
148  std::move(Compilations));
149  AdjustingCompilations->appendArgumentsAdjuster(
151  AdjustingCompilations->appendArgumentsAdjuster(
153  Compilations = std::move(AdjustingCompilations);
154 }
static std::unique_ptr< CompilationDatabase > autoDetectFromDirectory(StringRef SourceDir, std::string &ErrorMessage)
Tries to detect a compilation database location and load it.
ArgumentsAdjuster getInsertArgumentAdjuster(const CommandLineArguments &Extra, ArgumentInsertPosition Pos)
Gets an argument adjuster which inserts Extra arguments in the specified position.
const StringRef FilePath
int Category
Definition: Format.cpp:1304
std::function< CommandLineArguments(const CommandLineArguments &, StringRef Filename)> ArgumentsAdjuster
A prototype of a command line adjuster.
CommonOptionsParser(int &argc, const char **argv, llvm::cl::OptionCategory &Category, const char *Overview=nullptr)
Parses command-line, initializes a compilation database.
Interface for compilation databases.
static std::unique_ptr< FixedCompilationDatabase > loadFromCommandLine(int &Argc, const char *const *Argv, std::string &ErrorMsg, Twine Directory=".")
Creates a FixedCompilationDatabase from the arguments after "--".
Specifies the working directory and command of a compilation.
static std::unique_ptr< CompilationDatabase > autoDetectFromSource(StringRef SourceFile, std::string &ErrorMessage)
Tries to detect a compilation database location and load it.
A compilation database that returns a single compile command line.