xref: /llvm-project/clang-tools-extra/clang-query/tool/ClangQuery.cpp (revision 329be894f1118e906b13c86e1b77426d335aa1eb)
1 //===---- ClangQuery.cpp - clang-query tool -------------------------------===//
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 tool is for interactive exploration of the Clang AST using AST matchers.
11 // It currently allows the user to enter a matcher at an interactive prompt and
12 // view the resulting bindings as diagnostics, AST pretty prints or AST dumps.
13 // Example session:
14 //
15 // $ cat foo.c
16 // void foo(void) {}
17 // $ clang-query foo.c --
18 // clang-query> match functionDecl()
19 //
20 // Match #1:
21 //
22 // foo.c:1:1: note: "root" binds here
23 // void foo(void) {}
24 // ^~~~~~~~~~~~~~~~~
25 // 1 match.
26 //
27 //===----------------------------------------------------------------------===//
28 
29 #include "Query.h"
30 #include "QueryParser.h"
31 #include "QuerySession.h"
32 #include "clang/Frontend/ASTUnit.h"
33 #include "clang/Tooling/CompilationDatabase.h"
34 #include "clang/Tooling/Tooling.h"
35 #include "llvm/LineEditor/LineEditor.h"
36 #include "llvm/Support/CommandLine.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::opt<std::string> BuildPath("b", cl::desc("Specify build path"),
50                                       cl::value_desc("<path>"));
51 
52 static cl::list<std::string> Commands("c", cl::desc("Specify command to run"),
53                                       cl::value_desc("<command>"));
54 
55 static cl::list<std::string> CommandFiles("f",
56                                           cl::desc("Read commands from file"),
57                                           cl::value_desc("<file>"));
58 
59 static cl::list<std::string> SourcePaths(cl::Positional,
60                                          cl::desc("<source0> [... <sourceN>]"),
61                                          cl::OneOrMore);
62 
63 int main(int argc, const char **argv) {
64   llvm::sys::PrintStackTraceOnErrorSignal();
65   cl::ParseCommandLineOptions(argc, argv);
66 
67   if (!Commands.empty() && !CommandFiles.empty()) {
68     llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
69     return 1;
70   }
71 
72   std::unique_ptr<CompilationDatabase> Compilations(
73       FixedCompilationDatabase::loadFromCommandLine(argc, argv));
74   if (!Compilations) {  // Couldn't find a compilation DB from the command line
75     std::string ErrorMessage;
76     Compilations.reset(
77       !BuildPath.empty() ?
78         CompilationDatabase::autoDetectFromDirectory(BuildPath, ErrorMessage) :
79         CompilationDatabase::autoDetectFromSource(SourcePaths[0], ErrorMessage)
80       );
81 
82     // Still no compilation DB? - bail.
83     if (!Compilations)
84       llvm::report_fatal_error(ErrorMessage);
85   }
86 
87   ClangTool Tool(*Compilations, SourcePaths);
88   std::vector<std::unique_ptr<ASTUnit>> ASTs;
89   if (Tool.buildASTs(ASTs) != 0)
90     return 1;
91 
92   QuerySession QS(ASTs);
93 
94   if (!Commands.empty()) {
95     for (cl::list<std::string>::iterator I = Commands.begin(),
96                                          E = Commands.end();
97          I != E; ++I) {
98       QueryRef Q = QueryParser::parse(I->c_str(), QS);
99       if (!Q->run(llvm::outs(), QS))
100         return 1;
101     }
102   } else if (!CommandFiles.empty()) {
103     for (cl::list<std::string>::iterator I = CommandFiles.begin(),
104                                          E = CommandFiles.end();
105          I != E; ++I) {
106       std::ifstream Input(I->c_str());
107       if (!Input.is_open()) {
108         llvm::errs() << argv[0] << ": cannot open " << *I << "\n";
109         return 1;
110       }
111       while (Input.good()) {
112         std::string Line;
113         std::getline(Input, Line);
114 
115         QueryRef Q = QueryParser::parse(Line.c_str(), QS);
116         if (!Q->run(llvm::outs(), QS))
117           return 1;
118       }
119     }
120   } else {
121     LineEditor LE("clang-query");
122     LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
123       return QueryParser::complete(Line, Pos, QS);
124     });
125     while (llvm::Optional<std::string> Line = LE.readLine()) {
126       QueryRef Q = QueryParser::parse(*Line, QS);
127       Q->run(llvm::outs(), QS);
128     }
129   }
130 
131   return 0;
132 }
133