HeaderSearch.h revision 1c2e9332fa69727425a3a2b912e36e2ab62083f8
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 "clang/Lex/ModuleMap.h" 19#include "llvm/ADT/StringMap.h" 20#include "llvm/ADT/StringSet.h" 21#include "llvm/Support/Allocator.h" 22#include <vector> 23 24namespace clang { 25 26class DiagnosticsEngine; 27class ExternalIdentifierLookup; 28class FileEntry; 29class FileManager; 30class IdentifierInfo; 31 32/// HeaderFileInfo - The preprocessor keeps track of this information for each 33/// file that is #included. 34struct HeaderFileInfo { 35 /// isImport - True if this is a #import'd or #pragma once file. 36 unsigned isImport : 1; 37 38 /// isPragmaOnce - True if this is #pragma once file. 39 unsigned isPragmaOnce : 1; 40 41 /// DirInfo - Keep track of whether this is a system header, and if so, 42 /// whether it is C++ clean or not. This can be set by the include paths or 43 /// by #pragma gcc system_header. This is an instance of 44 /// SrcMgr::CharacteristicKind. 45 unsigned DirInfo : 2; 46 47 /// \brief Whether this header file info was supplied by an external source. 48 unsigned External : 1; 49 50 /// \brief Whether this structure is considered to already have been 51 /// "resolved", meaning that it was loaded from the external source. 52 unsigned Resolved : 1; 53 54 /// \brief Whether this is a header inside a framework that is currently 55 /// being built. 56 /// 57 /// When a framework is being built, the headers have not yet been placed 58 /// into the appropriate framework subdirectories, and therefore are 59 /// provided via a header map. This bit indicates when this is one of 60 /// those framework headers. 61 unsigned IndexHeaderMapHeader : 1; 62 63 /// NumIncludes - This is the number of times the file has been included 64 /// already. 65 unsigned short NumIncludes; 66 67 /// \brief The ID number of the controlling macro. 68 /// 69 /// This ID number will be non-zero when there is a controlling 70 /// macro whose IdentifierInfo may not yet have been loaded from 71 /// external storage. 72 unsigned ControllingMacroID; 73 74 /// ControllingMacro - If this file has a #ifndef XXX (or equivalent) guard 75 /// that protects the entire contents of the file, this is the identifier 76 /// for the macro that controls whether or not it has any effect. 77 /// 78 /// Note: Most clients should use getControllingMacro() to access 79 /// the controlling macro of this header, since 80 /// getControllingMacro() is able to load a controlling macro from 81 /// external storage. 82 const IdentifierInfo *ControllingMacro; 83 84 /// \brief If this header came from a framework include, this is the name 85 /// of the framework. 86 StringRef Framework; 87 88 HeaderFileInfo() 89 : isImport(false), isPragmaOnce(false), DirInfo(SrcMgr::C_User), 90 External(false), Resolved(false), IndexHeaderMapHeader(false), 91 NumIncludes(0), ControllingMacroID(0), ControllingMacro(0) {} 92 93 /// \brief Retrieve the controlling macro for this header file, if 94 /// any. 95 const IdentifierInfo *getControllingMacro(ExternalIdentifierLookup *External); 96 97 /// \brief Determine whether this is a non-default header file info, e.g., 98 /// it corresponds to an actual header we've included or tried to include. 99 bool isNonDefault() const { 100 return isImport || isPragmaOnce || NumIncludes || ControllingMacro || 101 ControllingMacroID; 102 } 103}; 104 105/// \brief An external source of header file information, which may supply 106/// information about header files already included. 107class ExternalHeaderFileInfoSource { 108public: 109 virtual ~ExternalHeaderFileInfoSource(); 110 111 /// \brief Retrieve the header file information for the given file entry. 112 /// 113 /// \returns Header file information for the given file entry, with the 114 /// \c External bit set. If the file entry is not known, return a 115 /// default-constructed \c HeaderFileInfo. 116 virtual HeaderFileInfo GetHeaderFileInfo(const FileEntry *FE) = 0; 117}; 118 119/// HeaderSearch - This class encapsulates the information needed to find the 120/// file referenced by a #include or #include_next, (sub-)framework lookup, etc. 121class HeaderSearch { 122 FileManager &FileMgr; 123 DiagnosticsEngine &Diags; 124 /// #include search path information. Requests for #include "x" search the 125 /// directory of the #including file first, then each directory in SearchDirs 126 /// consecutively. Requests for <x> search the current dir first, then each 127 /// directory in SearchDirs, starting at AngledDirIdx, consecutively. If 128 /// NoCurDirSearch is true, then the check for the file in the current 129 /// directory is suppressed. 130 std::vector<DirectoryLookup> SearchDirs; 131 unsigned AngledDirIdx; 132 unsigned SystemDirIdx; 133 bool NoCurDirSearch; 134 135 /// \brief The path to the module cache. 136 std::string ModuleCachePath; 137 138 /// \brief The name of the module we're building. 139 std::string BuildingModule; 140 141 /// FileInfo - This contains all of the preprocessor-specific data about files 142 /// that are included. The vector is indexed by the FileEntry's UID. 143 /// 144 std::vector<HeaderFileInfo> FileInfo; 145 146 /// LookupFileCache - This is keeps track of each lookup performed by 147 /// LookupFile. The first part of the value is the starting index in 148 /// SearchDirs that the cached search was performed from. If there is a hit 149 /// and this value doesn't match the current query, the cache has to be 150 /// ignored. The second value is the entry in SearchDirs that satisfied the 151 /// query. 152 llvm::StringMap<std::pair<unsigned, unsigned>, llvm::BumpPtrAllocator> 153 LookupFileCache; 154 155 /// FrameworkMap - This is a collection mapping a framework or subframework 156 /// name like "Carbon" to the Carbon.framework directory. 157 llvm::StringMap<const DirectoryEntry *, llvm::BumpPtrAllocator> 158 FrameworkMap; 159 160 /// HeaderMaps - This is a mapping from FileEntry -> HeaderMap, uniquing 161 /// headermaps. This vector owns the headermap. 162 std::vector<std::pair<const FileEntry*, const HeaderMap*> > HeaderMaps; 163 164 /// \brief The mapping between modules and headers. 165 ModuleMap ModMap; 166 167 /// \brief Describes whether a given directory has a module map in it. 168 llvm::DenseMap<const DirectoryEntry *, bool> DirectoryHasModuleMap; 169 170 /// \brief Uniqued set of framework names, which is used to track which 171 /// headers were included as framework headers. 172 llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames; 173 174 /// \brief Entity used to resolve the identifier IDs of controlling 175 /// macros into IdentifierInfo pointers, as needed. 176 ExternalIdentifierLookup *ExternalLookup; 177 178 /// \brief Entity used to look up stored header file information. 179 ExternalHeaderFileInfoSource *ExternalSource; 180 181 // Various statistics we track for performance analysis. 182 unsigned NumIncluded; 183 unsigned NumMultiIncludeFileOptzn; 184 unsigned NumFrameworkLookups, NumSubFrameworkLookups; 185 186 // HeaderSearch doesn't support default or copy construction. 187 explicit HeaderSearch(); 188 explicit HeaderSearch(const HeaderSearch&); 189 void operator=(const HeaderSearch&); 190public: 191 HeaderSearch(FileManager &FM, DiagnosticsEngine &Diags); 192 ~HeaderSearch(); 193 194 FileManager &getFileMgr() const { return FileMgr; } 195 196 /// SetSearchPaths - Interface for setting the file search paths. 197 /// 198 void SetSearchPaths(const std::vector<DirectoryLookup> &dirs, 199 unsigned angledDirIdx, unsigned systemDirIdx, 200 bool noCurDirSearch) { 201 assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() && 202 "Directory indicies are unordered"); 203 SearchDirs = dirs; 204 AngledDirIdx = angledDirIdx; 205 SystemDirIdx = systemDirIdx; 206 NoCurDirSearch = noCurDirSearch; 207 //LookupFileCache.clear(); 208 } 209 210 /// AddSearchPath - Add an additional search path. 211 void AddSearchPath(const DirectoryLookup &dir, bool isAngled) { 212 unsigned idx = isAngled ? SystemDirIdx : AngledDirIdx; 213 SearchDirs.insert(SearchDirs.begin() + idx, dir); 214 if (!isAngled) 215 AngledDirIdx++; 216 SystemDirIdx++; 217 } 218 219 /// \brief Set the path to the module cache and the name of the module 220 /// we're building 221 void configureModules(StringRef CachePath, StringRef BuildingModule) { 222 ModuleCachePath = CachePath; 223 this->BuildingModule = BuildingModule; 224 } 225 226 /// \brief Retrieve the path to the module cache. 227 StringRef getModuleCachePath() const { return ModuleCachePath; } 228 229 /// ClearFileInfo - Forget everything we know about headers so far. 230 void ClearFileInfo() { 231 FileInfo.clear(); 232 } 233 234 void SetExternalLookup(ExternalIdentifierLookup *EIL) { 235 ExternalLookup = EIL; 236 } 237 238 ExternalIdentifierLookup *getExternalLookup() const { 239 return ExternalLookup; 240 } 241 242 /// \brief Set the external source of header information. 243 void SetExternalSource(ExternalHeaderFileInfoSource *ES) { 244 ExternalSource = ES; 245 } 246 247 /// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 248 /// return null on failure. 249 /// 250 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member 251 /// the file was found in, or null if not applicable. 252 /// 253 /// \param isAngled indicates whether the file reference is a <> reference. 254 /// 255 /// \param CurDir If non-null, the file was found in the specified directory 256 /// search location. This is used to implement #include_next. 257 /// 258 /// \param CurFileEnt If non-null, indicates where the #including file is, in 259 /// case a relative search is needed. 260 /// 261 /// \param SearchPath If non-null, will be set to the search path relative 262 /// to which the file was found. If the include path is absolute, SearchPath 263 /// will be set to an empty string. 264 /// 265 /// \param RelativePath If non-null, will be set to the path relative to 266 /// SearchPath at which the file was found. This only differs from the 267 /// Filename for framework includes. 268 /// 269 /// \param SuggestedModule If non-null, and the file found is semantically 270 /// part of a known module, this will be set to the module that should 271 /// be imported instead of preprocessing/parsing the file found. 272 const FileEntry *LookupFile(StringRef Filename, bool isAngled, 273 const DirectoryLookup *FromDir, 274 const DirectoryLookup *&CurDir, 275 const FileEntry *CurFileEnt, 276 SmallVectorImpl<char> *SearchPath, 277 SmallVectorImpl<char> *RelativePath, 278 ModuleMap::Module **SuggestedModule, 279 bool SkipCache = false); 280 281 /// LookupSubframeworkHeader - Look up a subframework for the specified 282 /// #include file. For example, if #include'ing <HIToolbox/HIToolbox.h> from 283 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox 284 /// is a subframework within Carbon.framework. If so, return the FileEntry 285 /// for the designated file, otherwise return null. 286 const FileEntry *LookupSubframeworkHeader( 287 StringRef Filename, 288 const FileEntry *RelativeFileEnt, 289 SmallVectorImpl<char> *SearchPath, 290 SmallVectorImpl<char> *RelativePath); 291 292 /// LookupFrameworkCache - Look up the specified framework name in our 293 /// framework cache, returning the DirectoryEntry it is in if we know, 294 /// otherwise, return null. 295 const DirectoryEntry *&LookupFrameworkCache(StringRef FWName) { 296 return FrameworkMap.GetOrCreateValue(FWName).getValue(); 297 } 298 299 /// ShouldEnterIncludeFile - Mark the specified file as a target of of a 300 /// #include, #include_next, or #import directive. Return false if #including 301 /// the file will have no effect or true if we should include it. 302 bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport); 303 304 305 /// getFileDirFlavor - Return whether the specified file is a normal header, 306 /// a system header, or a C++ friendly system header. 307 SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) { 308 return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo; 309 } 310 311 /// MarkFileIncludeOnce - Mark the specified file as a "once only" file, e.g. 312 /// due to #pragma once. 313 void MarkFileIncludeOnce(const FileEntry *File) { 314 HeaderFileInfo &FI = getFileInfo(File); 315 FI.isImport = true; 316 FI.isPragmaOnce = true; 317 } 318 319 /// MarkFileSystemHeader - Mark the specified file as a system header, e.g. 320 /// due to #pragma GCC system_header. 321 void MarkFileSystemHeader(const FileEntry *File) { 322 getFileInfo(File).DirInfo = SrcMgr::C_System; 323 } 324 325 /// IncrementIncludeCount - Increment the count for the number of times the 326 /// specified FileEntry has been entered. 327 void IncrementIncludeCount(const FileEntry *File) { 328 ++getFileInfo(File).NumIncludes; 329 } 330 331 /// SetFileControllingMacro - Mark the specified file as having a controlling 332 /// macro. This is used by the multiple-include optimization to eliminate 333 /// no-op #includes. 334 void SetFileControllingMacro(const FileEntry *File, 335 const IdentifierInfo *ControllingMacro) { 336 getFileInfo(File).ControllingMacro = ControllingMacro; 337 } 338 339 /// \brief Determine whether this file is intended to be safe from 340 /// multiple inclusions, e.g., it has #pragma once or a controlling 341 /// macro. 342 /// 343 /// This routine does not consider the effect of #import 344 bool isFileMultipleIncludeGuarded(const FileEntry *File); 345 346 /// CreateHeaderMap - This method returns a HeaderMap for the specified 347 /// FileEntry, uniquing them through the the 'HeaderMaps' datastructure. 348 const HeaderMap *CreateHeaderMap(const FileEntry *FE); 349 350 /// \brief Search in the module cache path for a module with the given 351 /// name. 352 /// 353 /// \param If non-NULL, will be set to the module file name we expected to 354 /// find (regardless of whether it was actually found or not). 355 /// 356 /// \param UmbrellaHeader If non-NULL, and no module was found in the module 357 /// cache, this routine will search in the framework paths to determine 358 /// whether a module can be built from an umbrella header. If so, the pointee 359 /// will be set to the path of the umbrella header. 360 /// 361 /// \returns A file describing the named module, if available, or NULL to 362 /// indicate that the module could not be found. 363 const FileEntry *lookupModule(StringRef ModuleName, 364 std::string *ModuleFileName = 0, 365 std::string *UmbrellaHeader = 0); 366 367 void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; } 368 369 /// \brief Determine whether there is a module map that may map the header 370 /// with the given file name to a (sub)module. 371 /// 372 /// \param Filename The name of the file. 373 /// 374 /// \param Root The "root" directory, at which we should stop looking for 375 /// module maps. 376 bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root); 377 378 /// \brief Retrieve the module that corresponds to the given file, if any. 379 ModuleMap::Module *findModuleForHeader(const FileEntry *File); 380 381 382 /// \brief Read the contents of the given module map file. 383 /// 384 /// \param File The module map file. 385 /// 386 /// \param OnlyModule If non-NULL, this will receive the 387 /// 388 /// \returns true if an error occurred, false otherwise. 389 bool loadModuleMapFile(const FileEntry *File); 390 391 /// \brief Retrieve a module with the given name. 392 /// 393 /// \param Name The name of the module to retrieve. 394 /// 395 /// \param AllowSearch If true, we're allowed to look for module maps within 396 /// the header search path. Otherwise, the module must already be known. 397 /// 398 /// \returns The module, if found; otherwise, null. 399 ModuleMap::Module *getModule(StringRef Name, bool AllowSearch = true); 400 401 /// \brief Retrieve a module with the given name, which may be part of the 402 /// given framework. 403 /// 404 /// \param Name The name of the module to retrieve. 405 /// 406 /// \param Dir The framework directory (e.g., ModuleName.framework). 407 /// 408 /// \returns The module, if found; otherwise, null. 409 ModuleMap::Module *getFrameworkModule(StringRef Name, 410 const DirectoryEntry *Dir); 411 412 /// \brief Retrieve the module map. 413 ModuleMap &getModuleMap() { return ModMap; } 414 415 unsigned header_file_size() const { return FileInfo.size(); } 416 417 // Used by ASTReader. 418 void setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID); 419 420 /// getFileInfo - Return the HeaderFileInfo structure for the specified 421 /// FileEntry. 422 const HeaderFileInfo &getFileInfo(const FileEntry *FE) const { 423 return const_cast<HeaderSearch*>(this)->getFileInfo(FE); 424 } 425 426 // Used by external tools 427 typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator; 428 search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); } 429 search_dir_iterator search_dir_end() const { return SearchDirs.end(); } 430 unsigned search_dir_size() const { return SearchDirs.size(); } 431 432 search_dir_iterator quoted_dir_begin() const { 433 return SearchDirs.begin(); 434 } 435 search_dir_iterator quoted_dir_end() const { 436 return SearchDirs.begin() + AngledDirIdx; 437 } 438 439 search_dir_iterator angled_dir_begin() const { 440 return SearchDirs.begin() + AngledDirIdx; 441 } 442 search_dir_iterator angled_dir_end() const { 443 return SearchDirs.begin() + SystemDirIdx; 444 } 445 446 search_dir_iterator system_dir_begin() const { 447 return SearchDirs.begin() + SystemDirIdx; 448 } 449 search_dir_iterator system_dir_end() const { return SearchDirs.end(); } 450 451 /// \brief Retrieve a uniqued framework name. 452 StringRef getUniqueFrameworkName(StringRef Framework); 453 454 void PrintStats(); 455 456 size_t getTotalMemory() const; 457 458private: 459 /// \brief Describes what happened when we tried to load a module map file. 460 enum LoadModuleMapResult { 461 /// \brief The module map file had already been loaded. 462 LMM_AlreadyLoaded, 463 /// \brief The module map file was loaded by this invocation. 464 LMM_NewlyLoaded, 465 /// \brief There is was directory with the given name. 466 LMM_NoDirectory, 467 /// \brief There was either no module map file or the module map file was 468 /// invalid. 469 LMM_InvalidModuleMap 470 }; 471 472 /// \brief Try to load the module map file in the given directory. 473 /// 474 /// \param DirName The name of the directory where we will look for a module 475 /// map file. 476 /// 477 /// \returns The result of attempting to load the module map file from the 478 /// named directory. 479 LoadModuleMapResult loadModuleMapFile(StringRef DirName); 480 481 /// \brief Try to load the module map file in the given directory. 482 /// 483 /// \param Dir The directory where we will look for a module map file. 484 /// 485 /// \returns The result of attempting to load the module map file from the 486 /// named directory. 487 LoadModuleMapResult loadModuleMapFile(const DirectoryEntry *Dir); 488 489 /// getFileInfo - Return the HeaderFileInfo structure for the specified 490 /// FileEntry. 491 HeaderFileInfo &getFileInfo(const FileEntry *FE); 492}; 493 494} // end namespace clang 495 496#endif 497