xref: /llvm-project/clang-tools-extra/clang-query/tool/ClangQuery.cpp (revision 71f557355ddaea358c43b151de3a0e045aaa0863)
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/Error.h"
37 #include "llvm/Support/MemoryBuffer.h"
38 #include "llvm/Support/Signals.h"
39 #include "llvm/Support/WithColor.h"
40 #include <optional>
41 #include <string>
42 
43 using namespace clang;
44 using namespace clang::ast_matchers;
45 using namespace clang::ast_matchers::dynamic;
46 using namespace clang::query;
47 using namespace clang::tooling;
48 using namespace llvm;
49 
50 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
51 static cl::OptionCategory ClangQueryCategory("clang-query options");
52 
53 static cl::opt<bool>
54     UseColor("use-color",
55              cl::desc(
56                  R"(Use colors in detailed AST output. If not set, colors
57 will be used if the terminal connected to
58 standard output supports colors.)"),
59              cl::init(false), cl::cat(ClangQueryCategory));
60 
61 static cl::list<std::string> Commands("c", cl::desc("Specify command to run"),
62                                       cl::value_desc("command"),
63                                       cl::cat(ClangQueryCategory));
64 
65 static cl::list<std::string> CommandFiles("f",
66                                           cl::desc("Read commands from file"),
67                                           cl::value_desc("file"),
68                                           cl::cat(ClangQueryCategory));
69 
70 static cl::opt<std::string> PreloadFile(
71     "preload",
72     cl::desc("Preload commands from file and start interactive mode"),
73     cl::value_desc("file"), cl::cat(ClangQueryCategory));
74 
75 bool runCommandsInFile(const char *ExeName, std::string const &FileName,
76                        QuerySession &QS) {
77   auto Buffer = llvm::MemoryBuffer::getFile(FileName);
78   if (!Buffer) {
79     llvm::errs() << ExeName << ": cannot open " << FileName << ": "
80                  << Buffer.getError().message() << "\n";
81     return true;
82   }
83 
84   StringRef FileContentRef(Buffer.get()->getBuffer());
85 
86   while (!FileContentRef.empty()) {
87     QueryRef Q = QueryParser::parse(FileContentRef, QS);
88     if (!Q->run(llvm::outs(), QS))
89       return true;
90     FileContentRef = Q->RemainingContent;
91   }
92   return false;
93 }
94 
95 int main(int argc, const char **argv) {
96   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
97 
98   llvm::Expected<CommonOptionsParser> OptionsParser =
99       CommonOptionsParser::create(argc, argv, ClangQueryCategory,
100                                   llvm::cl::OneOrMore);
101 
102   if (!OptionsParser) {
103     llvm::WithColor::error() << llvm::toString(OptionsParser.takeError());
104     return 1;
105   }
106 
107   if (!Commands.empty() && !CommandFiles.empty()) {
108     llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
109     return 1;
110   }
111 
112   if ((!Commands.empty() || !CommandFiles.empty()) && !PreloadFile.empty()) {
113     llvm::errs() << argv[0]
114                  << ": cannot specify both -c or -f with --preload\n";
115     return 1;
116   }
117 
118   ClangTool Tool(OptionsParser->getCompilations(),
119                  OptionsParser->getSourcePathList());
120 
121   if (UseColor.getNumOccurrences() > 0) {
122     ArgumentsAdjuster colorAdjustor = [](const CommandLineArguments &Args, StringRef /*unused*/) {
123       CommandLineArguments AdjustedArgs = Args;
124       if (UseColor)
125         AdjustedArgs.push_back("-fdiagnostics-color");
126       else
127         AdjustedArgs.push_back("-fno-diagnostics-color");
128       return AdjustedArgs;
129     };
130     Tool.appendArgumentsAdjuster(colorAdjustor);
131   }
132 
133   std::vector<std::unique_ptr<ASTUnit>> ASTs;
134   int ASTStatus = 0;
135   switch (Tool.buildASTs(ASTs)) {
136   case 0:
137     break;
138   case 1: // Building ASTs failed.
139     return 1;
140   case 2:
141     ASTStatus |= 1;
142     llvm::errs() << "Failed to build AST for some of the files, "
143                  << "results may be incomplete."
144                  << "\n";
145     break;
146   default:
147     llvm_unreachable("Unexpected status returned");
148   }
149 
150   QuerySession QS(ASTs);
151 
152   if (!Commands.empty()) {
153     for (auto &Command : Commands) {
154       QueryRef Q = QueryParser::parse(Command, QS);
155       if (!Q->run(llvm::outs(), QS))
156         return 1;
157     }
158   } else if (!CommandFiles.empty()) {
159     for (auto &CommandFile : CommandFiles) {
160       if (runCommandsInFile(argv[0], CommandFile, QS))
161         return 1;
162     }
163   } else {
164     if (!PreloadFile.empty()) {
165       if (runCommandsInFile(argv[0], PreloadFile, QS))
166         return 1;
167     }
168     LineEditor LE("clang-query");
169     LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
170       return QueryParser::complete(Line, Pos, QS);
171     });
172     while (llvm::Optional<std::string> Line = LE.readLine()) {
173       QueryRef Q = QueryParser::parse(*Line, QS);
174       Q->run(llvm::outs(), QS);
175       llvm::outs().flush();
176       if (QS.Terminate)
177         break;
178     }
179   }
180 
181   return ASTStatus;
182 }
183