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/MemoryBuffer.h"
37 #include "llvm/Support/Signals.h"
38 #include "llvm/Support/WithColor.h"
39 #include <fstream>
40 #include <string>
41
42 using namespace clang;
43 using namespace clang::ast_matchers;
44 using namespace clang::ast_matchers::dynamic;
45 using namespace clang::query;
46 using namespace clang::tooling;
47 using namespace llvm;
48
49 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
50 static cl::OptionCategory ClangQueryCategory("clang-query options");
51
52 static cl::list<std::string> Commands("c", cl::desc("Specify command to run"),
53 cl::value_desc("command"),
54 cl::cat(ClangQueryCategory));
55
56 static cl::list<std::string> CommandFiles("f",
57 cl::desc("Read commands from file"),
58 cl::value_desc("file"),
59 cl::cat(ClangQueryCategory));
60
61 static cl::opt<std::string> PreloadFile(
62 "preload",
63 cl::desc("Preload commands from file and start interactive mode"),
64 cl::value_desc("file"), cl::cat(ClangQueryCategory));
65
runCommandsInFile(const char * ExeName,std::string const & FileName,QuerySession & QS)66 bool runCommandsInFile(const char *ExeName, std::string const &FileName,
67 QuerySession &QS) {
68 std::ifstream Input(FileName.c_str());
69 if (!Input.is_open()) {
70 llvm::errs() << ExeName << ": cannot open " << FileName << "\n";
71 return 1;
72 }
73
74 std::string FileContent((std::istreambuf_iterator<char>(Input)),
75 std::istreambuf_iterator<char>());
76
77 StringRef FileContentRef(FileContent);
78 while (!FileContentRef.empty()) {
79 QueryRef Q = QueryParser::parse(FileContentRef, QS);
80 if (!Q->run(llvm::outs(), QS))
81 return true;
82 FileContentRef = Q->RemainingContent;
83 }
84 return false;
85 }
86
main(int argc,const char ** argv)87 int main(int argc, const char **argv) {
88 llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
89
90 llvm::Expected<CommonOptionsParser> OptionsParser =
91 CommonOptionsParser::create(argc, argv, ClangQueryCategory,
92 llvm::cl::OneOrMore);
93
94 if (!OptionsParser) {
95 llvm::WithColor::error() << llvm::toString(OptionsParser.takeError());
96 return 1;
97 }
98
99 if (!Commands.empty() && !CommandFiles.empty()) {
100 llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
101 return 1;
102 }
103
104 if ((!Commands.empty() || !CommandFiles.empty()) && !PreloadFile.empty()) {
105 llvm::errs() << argv[0]
106 << ": cannot specify both -c or -f with --preload\n";
107 return 1;
108 }
109
110 ClangTool Tool(OptionsParser->getCompilations(),
111 OptionsParser->getSourcePathList());
112 std::vector<std::unique_ptr<ASTUnit>> ASTs;
113 int ASTStatus = 0;
114 switch (Tool.buildASTs(ASTs)) {
115 case 0:
116 break;
117 case 1: // Building ASTs failed.
118 return 1;
119 case 2:
120 ASTStatus |= 1;
121 llvm::errs() << "Failed to build AST for some of the files, "
122 << "results may be incomplete."
123 << "\n";
124 break;
125 default:
126 llvm_unreachable("Unexpected status returned");
127 }
128
129 QuerySession QS(ASTs);
130
131 if (!Commands.empty()) {
132 for (auto &Command : Commands) {
133 QueryRef Q = QueryParser::parse(Command, QS);
134 if (!Q->run(llvm::outs(), QS))
135 return 1;
136 }
137 } else if (!CommandFiles.empty()) {
138 for (auto &CommandFile : CommandFiles) {
139 if (runCommandsInFile(argv[0], CommandFile, QS))
140 return 1;
141 }
142 } else {
143 if (!PreloadFile.empty()) {
144 if (runCommandsInFile(argv[0], PreloadFile, QS))
145 return 1;
146 }
147 LineEditor LE("clang-query");
148 LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
149 return QueryParser::complete(Line, Pos, QS);
150 });
151 while (llvm::Optional<std::string> Line = LE.readLine()) {
152 QueryRef Q = QueryParser::parse(*Line, QS);
153 Q->run(llvm::outs(), QS);
154 llvm::outs().flush();
155 if (QS.Terminate)
156 break;
157 }
158 }
159
160 return ASTStatus;
161 }
162