clang-tools  9.0.0
ClangQuery.cpp
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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 <fstream>
39 #include <string>
40 
41 using namespace clang;
42 using namespace clang::ast_matchers;
43 using namespace clang::ast_matchers::dynamic;
44 using namespace clang::query;
45 using namespace clang::tooling;
46 using namespace llvm;
47 
48 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
49 static cl::OptionCategory ClangQueryCategory("clang-query options");
50 
51 static cl::list<std::string> Commands("c", cl::desc("Specify command to run"),
52  cl::value_desc("command"),
53  cl::cat(ClangQueryCategory));
54 
55 static cl::list<std::string> CommandFiles("f",
56  cl::desc("Read commands from file"),
57  cl::value_desc("file"),
58  cl::cat(ClangQueryCategory));
59 
60 static cl::opt<std::string> PreloadFile(
61  "preload",
62  cl::desc("Preload commands from file and start interactive mode"),
63  cl::value_desc("file"), cl::cat(ClangQueryCategory));
64 
65 bool runCommandsInFile(const char *ExeName, std::string const &FileName,
66  QuerySession &QS) {
67  std::ifstream Input(FileName.c_str());
68  if (!Input.is_open()) {
69  llvm::errs() << ExeName << ": cannot open " << FileName << "\n";
70  return 1;
71  }
72  while (Input.good()) {
73  std::string Line;
74  std::getline(Input, Line);
75 
76  QueryRef Q = QueryParser::parse(Line, QS);
77  if (!Q->run(llvm::outs(), QS))
78  return true;
79  }
80  return false;
81 }
82 
83 int main(int argc, const char **argv) {
84  llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
85 
86  CommonOptionsParser OptionsParser(argc, argv, ClangQueryCategory);
87 
88  if (!Commands.empty() && !CommandFiles.empty()) {
89  llvm::errs() << argv[0] << ": cannot specify both -c and -f\n";
90  return 1;
91  }
92 
93  if ((!Commands.empty() || !CommandFiles.empty()) && !PreloadFile.empty()) {
94  llvm::errs() << argv[0]
95  << ": cannot specify both -c or -f with --preload\n";
96  return 1;
97  }
98 
99  ClangTool Tool(OptionsParser.getCompilations(),
100  OptionsParser.getSourcePathList());
101  std::vector<std::unique_ptr<ASTUnit>> ASTs;
102  int Status = Tool.buildASTs(ASTs);
103  int ASTStatus = 0;
104  if (Status == 1) {
105  // Building ASTs failed.
106  return 1;
107  } else if (Status == 2) {
108  ASTStatus |= 1;
109  llvm::errs() << "Failed to build AST for some of the files, "
110  << "results may be incomplete."
111  << "\n";
112  } else {
113  assert(Status == 0 && "Unexpected status returned");
114  }
115 
116  QuerySession QS(ASTs);
117 
118  if (!Commands.empty()) {
119  for (auto I = Commands.begin(), E = Commands.end(); I != E; ++I) {
120  QueryRef Q = QueryParser::parse(*I, QS);
121  if (!Q->run(llvm::outs(), QS))
122  return 1;
123  }
124  } else if (!CommandFiles.empty()) {
125  for (auto I = CommandFiles.begin(), E = CommandFiles.end(); I != E; ++I) {
126  if (runCommandsInFile(argv[0], *I, QS))
127  return 1;
128  }
129  } else {
130  if (!PreloadFile.empty()) {
131  if (runCommandsInFile(argv[0], PreloadFile, QS))
132  return 1;
133  }
134  LineEditor LE("clang-query");
135  LE.setListCompleter([&QS](StringRef Line, size_t Pos) {
136  return QueryParser::complete(Line, Pos, QS);
137  });
138  while (llvm::Optional<std::string> Line = LE.readLine()) {
139  QueryRef Q = QueryParser::parse(*Line, QS);
140  Q->run(llvm::outs(), QS);
141  llvm::outs().flush();
142  if (QS.Terminate)
143  break;
144  }
145  }
146 
147  return ASTStatus;
148 }
Some operations such as code completion produce a set of candidates.
static cl::list< std::string > Commands("c", cl::desc("Specify command to run"), cl::value_desc("command"), cl::cat(ClangQueryCategory))
Represents the state for a particular clang-query session.
Definition: QuerySession.h:23
static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage)
static cl::OptionCategory ClangQueryCategory("clang-query options")
static cl::list< std::string > CommandFiles("f", cl::desc("Read commands from file"), cl::value_desc("file"), cl::cat(ClangQueryCategory))
static cl::opt< std::string > PreloadFile("preload", cl::desc("Preload commands from file and start interactive mode"), cl::value_desc("file"), cl::cat(ClangQueryCategory))
llvm::IntrusiveRefCntPtr< Query > QueryRef
Definition: Query.h:50
int main(int argc, const char **argv)
Definition: ClangQuery.cpp:83
PathRef FileName
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
bool runCommandsInFile(const char *ExeName, std::string const &FileName, QuerySession &QS)
Definition: ClangQuery.cpp:65