1 //===-- FileRemapper.h - File Remapping Helper ------------------*- C++ -*-===//
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 #ifndef LLVM_CLANG_ARCMIGRATE_FILEREMAPPER_H
10 #define LLVM_CLANG_ARCMIGRATE_FILEREMAPPER_H
11 
12 #include "clang/Basic/FileEntry.h"
13 #include "clang/Basic/LLVM.h"
14 #include "llvm/ADT/DenseMap.h"
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/ADT/StringRef.h"
17 #include <memory>
18 #include <variant>
19 
20 namespace llvm {
21   class MemoryBuffer;
22   class MemoryBufferRef;
23 }
24 
25 namespace clang {
26   class FileManager;
27   class DiagnosticsEngine;
28   class PreprocessorOptions;
29 
30 namespace arcmt {
31 
32 class FileRemapper {
33   // FIXME: Reuse the same FileManager for multiple ASTContexts.
34   std::unique_ptr<FileManager> FileMgr;
35 
36   using Target = std::variant<FileEntryRef, llvm::MemoryBuffer *>;
37   using MappingsTy = llvm::DenseMap<FileEntryRef, Target>;
38   MappingsTy FromToMappings;
39 
40   llvm::DenseMap<const FileEntry *, FileEntryRef> ToFromMappings;
41 
42 public:
43   FileRemapper();
44   ~FileRemapper();
45 
46   bool initFromDisk(StringRef outputDir, DiagnosticsEngine &Diag,
47                     bool ignoreIfFilesChanged);
48   bool initFromFile(StringRef filePath, DiagnosticsEngine &Diag,
49                     bool ignoreIfFilesChanged);
50   bool flushToDisk(StringRef outputDir, DiagnosticsEngine &Diag);
51   bool flushToFile(StringRef outputPath, DiagnosticsEngine &Diag);
52 
53   bool overwriteOriginal(DiagnosticsEngine &Diag,
54                          StringRef outputDir = StringRef());
55 
56   void remap(StringRef filePath, std::unique_ptr<llvm::MemoryBuffer> memBuf);
57 
58   void applyMappings(PreprocessorOptions &PPOpts) const;
59 
60   /// Iterate through all the mappings.
61   void forEachMapping(
62       llvm::function_ref<void(StringRef, StringRef)> CaptureFile,
63       llvm::function_ref<void(StringRef, const llvm::MemoryBufferRef &)>
64           CaptureBuffer) const;
65 
66   void clear(StringRef outputDir = StringRef());
67 
68 private:
69   void remap(FileEntryRef file, std::unique_ptr<llvm::MemoryBuffer> memBuf);
70   void remap(FileEntryRef file, FileEntryRef newfile);
71 
72   OptionalFileEntryRef getOriginalFile(StringRef filePath);
73   void resetTarget(Target &targ);
74 
75   bool report(const Twine &err, DiagnosticsEngine &Diag);
76 
77   std::string getRemapInfoFile(StringRef outputDir);
78 };
79 
80 } // end namespace arcmt
81 
82 }  // end namespace clang
83 
84 #endif
85