HeaderSearch.h revision 65e02fa80e1c185f18e5f81cefc30d75383a7301
1//===--- HeaderSearch.h - Resolve Header File Locations ---------*- 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 HeaderSearch interface. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_CLANG_LEX_HEADERSEARCH_H 15#define LLVM_CLANG_LEX_HEADERSEARCH_H 16 17#include "clang/Lex/DirectoryLookup.h" 18#include "llvm/ADT/StringMap.h" 19#include "llvm/ADT/StringSet.h" 20#include "llvm/Support/Allocator.h" 21#include <vector> 22 23namespace clang { 24 25class ExternalIdentifierLookup; 26class FileEntry; 27class FileManager; 28class IdentifierInfo; 29 30/// HeaderFileInfo - The preprocessor keeps track of this information for each 31/// file that is #included. 32struct HeaderFileInfo { 33 /// isImport - True if this is a #import'd or #pragma once file. 34 unsigned isImport : 1; 35 36 /// isPragmaOnce - True if this is #pragma once file. 37 unsigned isPragmaOnce : 1; 38 39 /// DirInfo - Keep track of whether this is a system header, and if so, 40 /// whether it is C++ clean or not. This can be set by the include paths or 41 /// by #pragma gcc system_header. This is an instance of 42 /// SrcMgr::CharacteristicKind. 43 unsigned DirInfo : 2; 44 45 /// \brief Whether this header file info was supplied by an external source. 46 unsigned External : 1; 47 48 /// \brief Whether this structure is considered to already have been 49 /// "resolved", meaning that it was loaded from the external source. 50 unsigned Resolved : 1; 51 52 /// \brief Whether this is a header inside a framework that is currently 53 /// being built. 54 /// 55 /// When a framework is being built, the headers have not yet been placed 56 /// into the appropriate framework subdirectories, and therefore are 57 /// provided via a header map. This bit indicates when this is one of 58 /// those framework headers. 59 unsigned IndexHeaderMapHeader : 1; 60 61 /// NumIncludes - This is the number of times the file has been included 62 /// already. 63 unsigned short NumIncludes; 64 65 /// \brief The ID number of the controlling macro. 66 /// 67 /// This ID number will be non-zero when there is a controlling 68 /// macro whose IdentifierInfo may not yet have been loaded from 69 /// external storage. 70 unsigned ControllingMacroID; 71 72 /// ControllingMacro - If this file has a #ifndef XXX (or equivalent) guard 73 /// that protects the entire contents of the file, this is the identifier 74 /// for the macro that controls whether or not it has any effect. 75 /// 76 /// Note: Most clients should use getControllingMacro() to access 77 /// the controlling macro of this header, since 78 /// getControllingMacro() is able to load a controlling macro from 79 /// external storage. 80 const IdentifierInfo *ControllingMacro; 81 82 /// \brief If this header came from a framework include, this is the name 83 /// of the framework. 84 StringRef Framework; 85 86 HeaderFileInfo() 87 : isImport(false), isPragmaOnce(false), DirInfo(SrcMgr::C_User), 88 External(false), Resolved(false), IndexHeaderMapHeader(false), 89 NumIncludes(0), ControllingMacroID(0), ControllingMacro(0) {} 90 91 /// \brief Retrieve the controlling macro for this header file, if 92 /// any. 93 const IdentifierInfo *getControllingMacro(ExternalIdentifierLookup *External); 94 95 /// \brief Determine whether this is a non-default header file info, e.g., 96 /// it corresponds to an actual header we've included or tried to include. 97 bool isNonDefault() const { 98 return isImport || isPragmaOnce || NumIncludes || ControllingMacro || 99 ControllingMacroID; 100 } 101}; 102 103/// \brief An external source of header file information, which may supply 104/// information about header files already included. 105class ExternalHeaderFileInfoSource { 106public: 107 virtual ~ExternalHeaderFileInfoSource(); 108 109 /// \brief Retrieve the header file information for the given file entry. 110 /// 111 /// \returns Header file information for the given file entry, with the 112 /// \c External bit set. If the file entry is not known, return a 113 /// default-constructed \c HeaderFileInfo. 114 virtual HeaderFileInfo GetHeaderFileInfo(const FileEntry *FE) = 0; 115}; 116 117/// HeaderSearch - This class encapsulates the information needed to find the 118/// file referenced by a #include or #include_next, (sub-)framework lookup, etc. 119class HeaderSearch { 120 FileManager &FileMgr; 121 /// #include search path information. Requests for #include "x" search the 122 /// directory of the #including file first, then each directory in SearchDirs 123 /// consecutively. Requests for <x> search the current dir first, then each 124 /// directory in SearchDirs, starting at AngledDirIdx, consecutively. If 125 /// NoCurDirSearch is true, then the check for the file in the current 126 /// directory is suppressed. 127 std::vector<DirectoryLookup> SearchDirs; 128 unsigned AngledDirIdx; 129 unsigned SystemDirIdx; 130 bool NoCurDirSearch; 131 132 /// FileInfo - This contains all of the preprocessor-specific data about files 133 /// that are included. The vector is indexed by the FileEntry's UID. 134 /// 135 std::vector<HeaderFileInfo> FileInfo; 136 137 /// LookupFileCache - This is keeps track of each lookup performed by 138 /// LookupFile. The first part of the value is the starting index in 139 /// SearchDirs that the cached search was performed from. If there is a hit 140 /// and this value doesn't match the current query, the cache has to be 141 /// ignored. The second value is the entry in SearchDirs that satisfied the 142 /// query. 143 llvm::StringMap<std::pair<unsigned, unsigned>, llvm::BumpPtrAllocator> 144 LookupFileCache; 145 146 147 /// FrameworkMap - This is a collection mapping a framework or subframework 148 /// name like "Carbon" to the Carbon.framework directory. 149 llvm::StringMap<const DirectoryEntry *, llvm::BumpPtrAllocator> 150 FrameworkMap; 151 152 /// HeaderMaps - This is a mapping from FileEntry -> HeaderMap, uniquing 153 /// headermaps. This vector owns the headermap. 154 std::vector<std::pair<const FileEntry*, const HeaderMap*> > HeaderMaps; 155 156 /// \brief Uniqued set of framework names, which is used to track which 157 /// headers were included as framework headers. 158 llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames; 159 160 /// \brief Entity used to resolve the identifier IDs of controlling 161 /// macros into IdentifierInfo pointers, as needed. 162 ExternalIdentifierLookup *ExternalLookup; 163 164 /// \brief Entity used to look up stored header file information. 165 ExternalHeaderFileInfoSource *ExternalSource; 166 167 // Various statistics we track for performance analysis. 168 unsigned NumIncluded; 169 unsigned NumMultiIncludeFileOptzn; 170 unsigned NumFrameworkLookups, NumSubFrameworkLookups; 171 172 // HeaderSearch doesn't support default or copy construction. 173 explicit HeaderSearch(); 174 explicit HeaderSearch(const HeaderSearch&); 175 void operator=(const HeaderSearch&); 176public: 177 HeaderSearch(FileManager &FM); 178 ~HeaderSearch(); 179 180 FileManager &getFileMgr() const { return FileMgr; } 181 182 /// SetSearchPaths - Interface for setting the file search paths. 183 /// 184 void SetSearchPaths(const std::vector<DirectoryLookup> &dirs, 185 unsigned angledDirIdx, unsigned systemDirIdx, 186 bool noCurDirSearch) { 187 assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() && 188 "Directory indicies are unordered"); 189 SearchDirs = dirs; 190 AngledDirIdx = angledDirIdx; 191 SystemDirIdx = systemDirIdx; 192 NoCurDirSearch = noCurDirSearch; 193 //LookupFileCache.clear(); 194 } 195 196 /// ClearFileInfo - Forget everything we know about headers so far. 197 void ClearFileInfo() { 198 FileInfo.clear(); 199 } 200 201 void SetExternalLookup(ExternalIdentifierLookup *EIL) { 202 ExternalLookup = EIL; 203 } 204 205 ExternalIdentifierLookup *getExternalLookup() const { 206 return ExternalLookup; 207 } 208 209 /// \brief Set the external source of header information. 210 void SetExternalSource(ExternalHeaderFileInfoSource *ES) { 211 ExternalSource = ES; 212 } 213 214 /// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 215 /// return null on failure. 216 /// 217 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member 218 /// the file was found in, or null if not applicable. 219 /// 220 /// \param isAngled indicates whether the file reference is a <> reference. 221 /// 222 /// \param CurDir If non-null, the file was found in the specified directory 223 /// search location. This is used to implement #include_next. 224 /// 225 /// \param CurFileEnt If non-null, indicates where the #including file is, in 226 /// case a relative search is needed. 227 /// 228 /// \param SearchPath If non-null, will be set to the search path relative 229 /// to which the file was found. If the include path is absolute, SearchPath 230 /// will be set to an empty string. 231 /// 232 /// \param RelativePath If non-null, will be set to the path relative to 233 /// SearchPath at which the file was found. This only differs from the 234 /// Filename for framework includes. 235 const FileEntry *LookupFile(StringRef Filename, bool isAngled, 236 const DirectoryLookup *FromDir, 237 const DirectoryLookup *&CurDir, 238 const FileEntry *CurFileEnt, 239 SmallVectorImpl<char> *SearchPath, 240 SmallVectorImpl<char> *RelativePath); 241 242 /// LookupSubframeworkHeader - Look up a subframework for the specified 243 /// #include file. For example, if #include'ing <HIToolbox/HIToolbox.h> from 244 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox 245 /// is a subframework within Carbon.framework. If so, return the FileEntry 246 /// for the designated file, otherwise return null. 247 const FileEntry *LookupSubframeworkHeader( 248 StringRef Filename, 249 const FileEntry *RelativeFileEnt, 250 SmallVectorImpl<char> *SearchPath, 251 SmallVectorImpl<char> *RelativePath); 252 253 /// LookupFrameworkCache - Look up the specified framework name in our 254 /// framework cache, returning the DirectoryEntry it is in if we know, 255 /// otherwise, return null. 256 const DirectoryEntry *&LookupFrameworkCache(StringRef FWName) { 257 return FrameworkMap.GetOrCreateValue(FWName).getValue(); 258 } 259 260 /// ShouldEnterIncludeFile - Mark the specified file as a target of of a 261 /// #include, #include_next, or #import directive. Return false if #including 262 /// the file will have no effect or true if we should include it. 263 bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport); 264 265 266 /// getFileDirFlavor - Return whether the specified file is a normal header, 267 /// a system header, or a C++ friendly system header. 268 SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) { 269 return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo; 270 } 271 272 /// MarkFileIncludeOnce - Mark the specified file as a "once only" file, e.g. 273 /// due to #pragma once. 274 void MarkFileIncludeOnce(const FileEntry *File) { 275 HeaderFileInfo &FI = getFileInfo(File); 276 FI.isImport = true; 277 FI.isPragmaOnce = true; 278 } 279 280 /// MarkFileSystemHeader - Mark the specified file as a system header, e.g. 281 /// due to #pragma GCC system_header. 282 void MarkFileSystemHeader(const FileEntry *File) { 283 getFileInfo(File).DirInfo = SrcMgr::C_System; 284 } 285 286 /// IncrementIncludeCount - Increment the count for the number of times the 287 /// specified FileEntry has been entered. 288 void IncrementIncludeCount(const FileEntry *File) { 289 ++getFileInfo(File).NumIncludes; 290 } 291 292 /// SetFileControllingMacro - Mark the specified file as having a controlling 293 /// macro. This is used by the multiple-include optimization to eliminate 294 /// no-op #includes. 295 void SetFileControllingMacro(const FileEntry *File, 296 const IdentifierInfo *ControllingMacro) { 297 getFileInfo(File).ControllingMacro = ControllingMacro; 298 } 299 300 /// \brief Determine whether this file is intended to be safe from 301 /// multiple inclusions, e.g., it has #pragma once or a controlling 302 /// macro. 303 /// 304 /// This routine does not consider the effect of #import 305 bool isFileMultipleIncludeGuarded(const FileEntry *File); 306 307 /// CreateHeaderMap - This method returns a HeaderMap for the specified 308 /// FileEntry, uniquing them through the the 'HeaderMaps' datastructure. 309 const HeaderMap *CreateHeaderMap(const FileEntry *FE); 310 311 void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; } 312 313 typedef std::vector<HeaderFileInfo>::const_iterator header_file_iterator; 314 header_file_iterator header_file_begin() const { return FileInfo.begin(); } 315 header_file_iterator header_file_end() const { return FileInfo.end(); } 316 unsigned header_file_size() const { return FileInfo.size(); } 317 318 // Used by ASTReader. 319 void setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID); 320 321 // Used by external tools 322 typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator; 323 search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); } 324 search_dir_iterator search_dir_end() const { return SearchDirs.end(); } 325 unsigned search_dir_size() const { return SearchDirs.size(); } 326 327 search_dir_iterator quoted_dir_begin() const { 328 return SearchDirs.begin(); 329 } 330 search_dir_iterator quoted_dir_end() const { 331 return SearchDirs.begin() + AngledDirIdx; 332 } 333 334 search_dir_iterator angled_dir_begin() const { 335 return SearchDirs.begin() + AngledDirIdx; 336 } 337 search_dir_iterator angled_dir_end() const { 338 return SearchDirs.begin() + SystemDirIdx; 339 } 340 341 search_dir_iterator system_dir_begin() const { 342 return SearchDirs.begin() + SystemDirIdx; 343 } 344 search_dir_iterator system_dir_end() const { return SearchDirs.end(); } 345 346 /// \brief Retrieve a uniqued framework name. 347 StringRef getUniqueFrameworkName(StringRef Framework); 348 349 void PrintStats(); 350 351 size_t getTotalMemory() const; 352 353private: 354 355 /// getFileInfo - Return the HeaderFileInfo structure for the specified 356 /// FileEntry. 357 HeaderFileInfo &getFileInfo(const FileEntry *FE); 358}; 359 360} // end namespace clang 361 362#endif 363