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
30using namespace clang::tooling;
31using namespace llvm;
32
33const 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
55void ArgumentsAdjustingCompilations::appendArgumentsAdjuster(
56 ArgumentsAdjuster Adjuster) {
57 Adjusters.push_back(x: std::move(Adjuster));
58}
59
60std::vector<CompileCommand> ArgumentsAdjustingCompilations::getCompileCommands(
61 StringRef FilePath) const {
62 return adjustCommands(Commands: Compilations->getCompileCommands(FilePath));
63}
64
65std::vector<std::string>
66ArgumentsAdjustingCompilations::getAllFiles() const {
67 return Compilations->getAllFiles();
68}
69
70std::vector<CompileCommand>
71ArgumentsAdjustingCompilations::getAllCompileCommands() const {
72 return adjustCommands(Commands: Compilations->getAllCompileCommands());
73}
74
75std::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
83llvm::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&: argc, Argv: argv, ErrorMsg&: ErrorMessage);
112 if (!ErrorMessage.empty())
113 ErrorMessage.append(s: "\n");
114 llvm::raw_string_ostream OS(ErrorMessage);
115 // Stop initializing if command-line option parsing failed.
116 if (!cl::ParseCommandLineOptions(argc, argv, Overview, Errs: &OS)) {
117 return llvm::make_error<llvm::StringError>(Args&: ErrorMessage,
118 Args: 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(SourceDir: BuildPath, ErrorMessage);
131 } else {
132 Compilations = CompilationDatabase::autoDetectFromSource(SourceFile: 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 p: new FixedCompilationDatabase(".", std::vector<std::string>()));
140 }
141 }
142 auto AdjustingCompilations =
143 std::make_unique<ArgumentsAdjustingCompilations>(
144 args: std::move(Compilations));
145 Adjuster =
146 getInsertArgumentAdjuster(Extra: ArgsBefore, Pos: ArgumentInsertPosition::BEGIN);
147 Adjuster = combineAdjusters(
148 First: std::move(Adjuster),
149 Second: getInsertArgumentAdjuster(Extra: ArgsAfter, Pos: ArgumentInsertPosition::END));
150 AdjustingCompilations->appendArgumentsAdjuster(Adjuster);
151 Compilations = std::move(AdjustingCompilations);
152 return llvm::Error::success();
153}
154
155llvm::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
166CommonOptionsParser::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 reason: Twine("CommonOptionsParser: failed to parse command-line arguments. ") +
173 llvm::toString(E: std::move(Err)));
174 }
175}
176