clang  6.0.0svn
HeaderMap.h
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1 //===--- HeaderMap.h - A file that acts like dir of symlinks ----*- 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 HeaderMap interface.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LEX_HEADERMAP_H
15 #define LLVM_CLANG_LEX_HEADERMAP_H
16 
17 #include "clang/Basic/LLVM.h"
18 #include "llvm/ADT/Optional.h"
19 #include "llvm/Support/Compiler.h"
20 #include "llvm/Support/MemoryBuffer.h"
21 #include <memory>
22 
23 namespace clang {
24 
25 class FileEntry;
26 class FileManager;
27 struct HMapBucket;
28 struct HMapHeader;
29 
30 /// Implementation for \a HeaderMap that doesn't depend on \a FileManager.
32  std::unique_ptr<const llvm::MemoryBuffer> FileBuffer;
33  bool NeedsBSwap;
34 
35 public:
36  HeaderMapImpl(std::unique_ptr<const llvm::MemoryBuffer> File, bool NeedsBSwap)
37  : FileBuffer(std::move(File)), NeedsBSwap(NeedsBSwap) {}
38 
39  // Check for a valid header and extract the byte swap.
40  static bool checkHeader(const llvm::MemoryBuffer &File, bool &NeedsByteSwap);
41 
42  /// If the specified relative filename is located in this HeaderMap return
43  /// the filename it is mapped to, otherwise return an empty StringRef.
44  StringRef lookupFilename(StringRef Filename,
45  SmallVectorImpl<char> &DestPath) const;
46 
47  /// Return the filename of the headermap.
48  StringRef getFileName() const;
49 
50  /// Print the contents of this headermap to stderr.
51  void dump() const;
52 
53 private:
54  unsigned getEndianAdjustedWord(unsigned X) const;
55  const HMapHeader &getHeader() const;
56  HMapBucket getBucket(unsigned BucketNo) const;
57 
58  /// Look up the specified string in the string table. If the string index is
59  /// not valid, return None.
60  Optional<StringRef> getString(unsigned StrTabIdx) const;
61 };
62 
63 /// This class represents an Apple concept known as a 'header map'. To the
64 /// \#include file resolution process, it basically acts like a directory of
65 /// symlinks to files. Its advantages are that it is dense and more efficient
66 /// to create and process than a directory of symlinks.
67 class HeaderMap : private HeaderMapImpl {
68  HeaderMap(std::unique_ptr<const llvm::MemoryBuffer> File, bool BSwap)
69  : HeaderMapImpl(std::move(File), BSwap) {}
70 
71 public:
72  /// This attempts to load the specified file as a header map. If it doesn't
73  /// look like a HeaderMap, it gives up and returns null.
74  static const HeaderMap *Create(const FileEntry *FE, FileManager &FM);
75 
76  /// Check to see if the specified relative filename is located in this
77  /// HeaderMap. If so, open it and return its FileEntry. If RawPath is not
78  /// NULL and the file is found, RawPath will be set to the raw path at which
79  /// the file was found in the file system. For example, for a search path
80  /// ".." and a filename "../file.h" this would be "../../file.h".
81  const FileEntry *LookupFile(StringRef Filename, FileManager &FM) const;
82 
85  using HeaderMapImpl::dump;
86 };
87 
88 } // end namespace clang.
89 
90 #endif
Implements support for file system lookup, file system caching, and directory search management...
Definition: FileManager.h:116
static bool checkHeader(const llvm::MemoryBuffer &File, bool &NeedsByteSwap)
Definition: HeaderMap.cpp:65
StringRef lookupFilename(StringRef Filename, SmallVectorImpl< char > &DestPath) const
If the specified relative filename is located in this HeaderMap return the filename it is mapped to...
Definition: HeaderMap.cpp:210
This class represents an Apple concept known as a &#39;header map&#39;.
Definition: HeaderMap.h:67
Definition: Format.h:1900
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
void dump() const
Print the contents of this headermap to stderr.
Definition: HeaderMap.cpp:172
HeaderMapImpl(std::unique_ptr< const llvm::MemoryBuffer > File, bool NeedsBSwap)
Definition: HeaderMap.h:36
StringRef Filename
Definition: Format.cpp:1345
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:59
Dataflow Directional Tag Classes.
Implementation for HeaderMap that doesn&#39;t depend on FileManager.
Definition: HeaderMap.h:31
X
Add a minimal nested name specifier fixit hint to allow lookup of a tag name from an outer enclosing ...
Definition: SemaDecl.cpp:13010
StringRef getFileName() const
Return the filename of the headermap.
Definition: HeaderMap.cpp:109
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr *> VL, ArrayRef< Expr *> PL, ArrayRef< Expr *> IL, Expr *Step, Expr *CalcStep, Stmt *PreInit, Expr *PostUpdate)
Creates clause with a list of variables VL and a linear step Step.