xref: /llvm-project/clang-tools-extra/clang-query/tool/ClangQuery.cpp (revision 3f76260dc0674cc0acb25f550a0f0c594cf537ea)
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/InitLLVM.h"
37 #include "llvm/Support/MemoryBuffer.h"
38 #include "llvm/Support/Signals.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 
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   while (Input.good()) {
74     std::string Line;
75     std::getline(Input, Line);
76 
77     QueryRef Q = QueryParser::parse(Line, QS);
78     if (!Q->run(llvm::outs(), QS))
79       return true;
80   }
81   return false;
82 }
83 
84 int main(int argc, const char **argv) {
85   llvm::InitLLVM X(argc, argv);
86 
87   CommonOptionsParser OptionsParser(argc, argv, ClangQueryCategory);
88 
89   if (!Commands.empty() && !CommandFiles.empty()) {
90     llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
91     return 1;
92   }
93 
94   if ((!Commands.empty() || !CommandFiles.empty()) && !PreloadFile.empty()) {
95     llvm::errs() << argv[0]
96                  << ": cannot specify both -c or -f with --preload\n";
97     return 1;
98   }
99 
100   ClangTool Tool(OptionsParser.getCompilations(),
101                  OptionsParser.getSourcePathList());
102   std::vector<std::unique_ptr<ASTUnit>> ASTs;
103   int Status = Tool.buildASTs(ASTs);
104   int ASTStatus = 0;
105   if (Status == 1) {
106     // Building ASTs failed.
107     return 1;
108   } else if (Status == 2) {
109     ASTStatus |= 1;
110     llvm::errs() << "Failed to build AST for some of the files, "
111                  << "results may be incomplete."
112                  << "\n";
113   } else {
114     assert(Status == 0 && "Unexpected status returned");
115   }
116 
117   QuerySession QS(ASTs);
118 
119   if (!Commands.empty()) {
120     for (auto I = Commands.begin(), E = Commands.end(); I != E; ++I) {
121       QueryRef Q = QueryParser::parse(*I, QS);
122       if (!Q->run(llvm::outs(), QS))
123         return 1;
124     }
125   } else if (!CommandFiles.empty()) {
126     for (auto I = CommandFiles.begin(), E = CommandFiles.end(); I != E; ++I) {
127       if (runCommandsInFile(argv[0], *I, QS))
128         return 1;
129     }
130   } else {
131     if (!PreloadFile.empty()) {
132       if (runCommandsInFile(argv[0], PreloadFile, QS))
133         return 1;
134     }
135     LineEditor LE("clang-query");
136     LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
137       return QueryParser::complete(Line, Pos, QS);
138     });
139     while (llvm::Optional<std::string> Line = LE.readLine()) {
140       QueryRef Q = QueryParser::parse(*Line, QS);
141       Q->run(llvm::outs(), QS);
142       llvm::outs().flush();
143       if (QS.Terminate)
144         break;
145     }
146   }
147 
148   return ASTStatus;
149 }
150