HeaderMap.h revision 1adbf6349d4701771a814542008386ad39e3d614
1//===--- HeaderMap.h - A file that acts like dir of symlinks ----*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by Chris Lattner and is distributed under 6// the University of Illinois Open Source 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 17namespace llvm { 18 class MemoryBuffer; 19} 20namespace clang { 21 class FileEntry; 22 class FileManager; 23 struct HMapBucket; 24 struct HMapHeader; 25 26/// This class represents an Apple concept known as a 'header map'. To the 27/// #include file resolution process, it basically acts like a directory of 28/// symlinks to files. Its advantages are that it is dense and more efficient 29/// to create and process than a directory of symlinks. 30class HeaderMap { 31 HeaderMap(const HeaderMap&); // DO NOT IMPLEMENT 32 void operator=(const HeaderMap&); // DO NOT IMPLEMENT 33 34 const llvm::MemoryBuffer *FileBuffer; 35 bool NeedsBSwap; 36 37 HeaderMap(const llvm::MemoryBuffer *File, bool BSwap) 38 : FileBuffer(File), NeedsBSwap(BSwap) { 39 } 40public: 41 ~HeaderMap(); 42 43 /// HeaderMap::Create - This attempts to load the specified file as a header 44 /// map. If it doesn't look like a HeaderMap, it gives up and returns null. 45 static const HeaderMap *Create(const FileEntry *FE); 46 47 /// LookupFile - Check to see if the specified relative filename is located in 48 /// this HeaderMap. If so, open it and return its FileEntry. 49 const FileEntry *LookupFile(const char *FilenameStart,const char *FilenameEnd, 50 FileManager &FM) const; 51 52 /// getFileName - Return the filename of the headermap. 53 const char *getFileName() const; 54 55 /// dump - Print the contents of this headermap to stderr. 56 void dump() const; 57 58private: 59 unsigned getEndianAdjustedWord(unsigned X) const; 60 const HMapHeader &getHeader() const; 61 HMapBucket getBucket(unsigned BucketNo) const; 62 const char *getString(unsigned StrTabIdx) const; 63}; 64 65} // end namespace clang. 66 67#endif