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"
28 #include "clang/Tooling/ArgumentsAdjusters.h"
29 #include "clang/Tooling/CommonOptionsParser.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 class ArgumentsAdjustingCompilations : public CompilationDatabase {
58 public:
59   ArgumentsAdjustingCompilations(
60       std::unique_ptr<CompilationDatabase> Compilations)
61       : Compilations(std::move(Compilations)) {}
62 
63   void appendArgumentsAdjuster(ArgumentsAdjuster Adjuster) {
64     Adjusters.push_back(Adjuster);
65   }
66 
67   std::vector<CompileCommand>
68   getCompileCommands(StringRef FilePath) const override {
69     return adjustCommands(Compilations->getCompileCommands(FilePath));
70   }
71 
72   std::vector<std::string> getAllFiles() const override {
73     return Compilations->getAllFiles();
74   }
75 
76   std::vector<CompileCommand> getAllCompileCommands() const override {
77     return adjustCommands(Compilations->getAllCompileCommands());
78   }
79 
80 private:
81   std::unique_ptr<CompilationDatabase> Compilations;
82   std::vector<ArgumentsAdjuster> Adjusters;
83 
84   std::vector<CompileCommand>
85   adjustCommands(std::vector<CompileCommand> Commands) const {
86     for (CompileCommand &Command : Commands)
87       for (const auto &Adjuster : Adjusters)
88         Command.CommandLine = Adjuster(Command.CommandLine);
89     return Commands;
90   }
91 };
92 
93 CommonOptionsParser::CommonOptionsParser(int &argc, const char **argv,
94                                          cl::OptionCategory &Category,
95                                          const char *Overview) {
96   static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
97 
98   static cl::opt<std::string> BuildPath("p", cl::desc("Build path"),
99                                         cl::Optional, cl::cat(Category));
100 
101   static cl::list<std::string> SourcePaths(
102       cl::Positional, cl::desc("<source0> [... <sourceN>]"), cl::OneOrMore,
103       cl::cat(Category));
104 
105   static cl::list<std::string> ArgsAfter(
106       "extra-arg",
107       cl::desc("Additional argument to append to the compiler command line"),
108       cl::cat(Category));
109 
110   static cl::list<std::string> ArgsBefore(
111       "extra-arg-before",
112       cl::desc("Additional argument to prepend to the compiler command line"),
113       cl::cat(Category));
114 
115   cl::HideUnrelatedOptions(Category);
116 
117   Compilations.reset(FixedCompilationDatabase::loadFromCommandLine(argc,
118                                                                    argv));
119   cl::ParseCommandLineOptions(argc, argv, Overview);
120   SourcePathList = SourcePaths;
121   if (!Compilations) {
122     std::string ErrorMessage;
123     if (!BuildPath.empty()) {
124       Compilations =
125           CompilationDatabase::autoDetectFromDirectory(BuildPath, ErrorMessage);
126     } else {
127       Compilations = CompilationDatabase::autoDetectFromSource(SourcePaths[0],
128                                                                ErrorMessage);
129     }
130     if (!Compilations)
131       llvm::report_fatal_error(ErrorMessage);
132   }
133   auto AdjustingCompilations =
134       llvm::make_unique<ArgumentsAdjustingCompilations>(
135           std::move(Compilations));
136   AdjustingCompilations->appendArgumentsAdjuster(
137       getInsertArgumentAdjuster(ArgsBefore, ArgumentInsertPosition::BEGIN));
138   AdjustingCompilations->appendArgumentsAdjuster(
139       getInsertArgumentAdjuster(ArgsAfter, ArgumentInsertPosition::END));
140   Compilations = std::move(AdjustingCompilations);
141 }
142