PPCallbacks.h revision 7633ab80454147ab4892b8de5fd16582a1f221e8 
1//===--- PPCallbacks.h - Callbacks for Preprocessor actions -----*- C++ -*-===//
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 file defines the PPCallbacks interface.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_LEX_PPCALLBACKS_H
15#define LLVM_CLANG_LEX_PPCALLBACKS_H
16
17#include "clang/Lex/DirectoryLookup.h"
18#include "clang/Basic/SourceLocation.h"
19#include <string>
20
21namespace clang {
22  class SourceLocation;
23  class Token;
24  class IdentifierInfo;
25  class MacroInfo;
26
27/// PPCallbacks - This interface provides a way to observe the actions of the
28/// preprocessor as it does its thing.  Clients can define their hooks here to
29/// implement preprocessor level tools.
30class PPCallbacks {
31public:
32  virtual ~PPCallbacks();
33
34  enum FileChangeReason {
35    EnterFile, ExitFile, SystemHeaderPragma, RenameFile
36  };
37
38  /// FileChanged - This callback is invoked whenever a source file is
39  /// entered or exited.  The SourceLocation indicates the new location, and
40  /// EnteringFile indicates whether this is because we are entering a new
41  /// #include'd file (when true) or whether we're exiting one because we ran
42  /// off the end (when false).
43  virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
44                           SrcMgr::CharacteristicKind FileType) {
45  }
46
47  /// Ident - This callback is invoked when a #ident or #sccs directive is read.
48  ///
49  virtual void Ident(SourceLocation Loc, const std::string &str) {
50  }
51
52  /// PragmaComment - This callback is invoked when a #pragma comment directive
53  /// is read.
54  ///
55  virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
56                             const std::string &Str) {
57  }
58
59  /// MacroExpands - This is called by
60  /// Preprocessor::HandleMacroExpandedIdentifier when a macro invocation is
61  /// found.
62  virtual void MacroExpands(const Token &Id, const MacroInfo* MI) {
63  }
64
65  /// MacroDefined - This hook is called whenever a macro definition is seen.
66  virtual void MacroDefined(const IdentifierInfo *II, const MacroInfo *MI) {
67  }
68
69  /// MacroUndefined - This hook is called whenever a macro #undef is seen.
70  /// MI is released immediately following this callback.
71  virtual void MacroUndefined(const IdentifierInfo *II, const MacroInfo *MI) {
72  }
73};
74
75/// PPChainedCallbacks - Simple wrapper class for chaining callbacks.
76class PPChainedCallbacks : public PPCallbacks {
77  PPCallbacks *First, *Second;
78
79public:
80  PPChainedCallbacks(PPCallbacks *_First, PPCallbacks *_Second)
81    : First(_First), Second(_Second) {}
82  ~PPChainedCallbacks() {
83    delete Second;
84    delete First;
85  }
86
87  virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
88                           SrcMgr::CharacteristicKind FileType) {
89    First->FileChanged(Loc, Reason, FileType);
90    Second->FileChanged(Loc, Reason, FileType);
91  }
92
93  virtual void Ident(SourceLocation Loc, const std::string &str) {
94    First->Ident(Loc, str);
95    Second->Ident(Loc, str);
96  }
97
98  virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
99                             const std::string &Str) {
100    First->PragmaComment(Loc, Kind, Str);
101    Second->PragmaComment(Loc, Kind, Str);
102  }
103
104  virtual void MacroExpands(const Token &Id, const MacroInfo* MI) {
105    First->MacroExpands(Id, MI);
106    Second->MacroExpands(Id, MI);
107  }
108
109  virtual void MacroDefined(const IdentifierInfo *II, const MacroInfo *MI) {
110    First->MacroDefined(II, MI);
111    Second->MacroDefined(II, MI);
112  }
113
114  virtual void MacroUndefined(const IdentifierInfo *II, const MacroInfo *MI) {
115    First->MacroUndefined(II, MI);
116    Second->MacroUndefined(II, MI);
117  }
118};
119
120}  // end namespace clang
121
122#endif
123