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/ArrayRef.h" 20 #include "llvm/ADT/IntrusiveRefCntPtr.h" 21 #include "llvm/ADT/OwningPtr.h" 22 #include "llvm/ADT/StringMap.h" 23 #include "llvm/ADT/StringSet.h" 24 #include "llvm/Support/Allocator.h" 25 #include <vector> 26 27 namespace clang { 28 29 class DiagnosticsEngine; 30 class ExternalIdentifierLookup; 31 class FileEntry; 32 class FileManager; 33 class HeaderSearchOptions; 34 class IdentifierInfo; 35 36 /// \brief The preprocessor keeps track of this information for each 37 /// file that is \#included. 38 struct HeaderFileInfo { 39 /// \brief True if this is a \#import'd or \#pragma once file. 40 unsigned isImport : 1; 41 42 /// \brief True if this is a \#pragma once file. 43 unsigned isPragmaOnce : 1; 44 45 /// DirInfo - Keep track of whether this is a system header, and if so, 46 /// whether it is C++ clean or not. This can be set by the include paths or 47 /// by \#pragma gcc system_header. This is an instance of 48 /// SrcMgr::CharacteristicKind. 49 unsigned DirInfo : 2; 50 51 /// \brief Whether this header file info was supplied by an external source. 52 unsigned External : 1; 53 54 /// \brief Whether this header is part of a module. 55 unsigned isModuleHeader : 1; 56 57 /// \brief Whether this structure is considered to already have been 58 /// "resolved", meaning that it was loaded from the external source. 59 unsigned Resolved : 1; 60 61 /// \brief Whether this is a header inside a framework that is currently 62 /// being built. 63 /// 64 /// When a framework is being built, the headers have not yet been placed 65 /// into the appropriate framework subdirectories, and therefore are 66 /// provided via a header map. This bit indicates when this is one of 67 /// those framework headers. 68 unsigned IndexHeaderMapHeader : 1; 69 70 /// \brief The number of times the file has been included already. 71 unsigned short NumIncludes; 72 73 /// \brief The ID number of the controlling macro. 74 /// 75 /// This ID number will be non-zero when there is a controlling 76 /// macro whose IdentifierInfo may not yet have been loaded from 77 /// external storage. 78 unsigned ControllingMacroID; 79 80 /// If this file has a \#ifndef XXX (or equivalent) guard that 81 /// protects the entire contents of the file, this is the identifier 82 /// for the macro that controls whether or not it has any effect. 83 /// 84 /// Note: Most clients should use getControllingMacro() to access 85 /// the controlling macro of this header, since 86 /// getControllingMacro() is able to load a controlling macro from 87 /// external storage. 88 const IdentifierInfo *ControllingMacro; 89 90 /// \brief If this header came from a framework include, this is the name 91 /// of the framework. 92 StringRef Framework; 93 94 HeaderFileInfo() 95 : isImport(false), isPragmaOnce(false), DirInfo(SrcMgr::C_User), 96 External(false), isModuleHeader(false), Resolved(false), 97 IndexHeaderMapHeader(false), 98 NumIncludes(0), ControllingMacroID(0), ControllingMacro(0) {} 99 100 /// \brief Retrieve the controlling macro for this header file, if 101 /// any. 102 const IdentifierInfo *getControllingMacro(ExternalIdentifierLookup *External); 103 104 /// \brief Determine whether this is a non-default header file info, e.g., 105 /// it corresponds to an actual header we've included or tried to include. 106 bool isNonDefault() const { 107 return isImport || isPragmaOnce || NumIncludes || ControllingMacro || 108 ControllingMacroID; 109 } 110 }; 111 112 /// \brief An external source of header file information, which may supply 113 /// information about header files already included. 114 class ExternalHeaderFileInfoSource { 115 public: 116 virtual ~ExternalHeaderFileInfoSource(); 117 118 /// \brief Retrieve the header file information for the given file entry. 119 /// 120 /// \returns Header file information for the given file entry, with the 121 /// \c External bit set. If the file entry is not known, return a 122 /// default-constructed \c HeaderFileInfo. 123 virtual HeaderFileInfo GetHeaderFileInfo(const FileEntry *FE) = 0; 124 }; 125 126 /// \brief Encapsulates the information needed to find the file referenced 127 /// by a \#include or \#include_next, (sub-)framework lookup, etc. 128 class HeaderSearch { 129 /// This structure is used to record entries in our framework cache. 130 struct FrameworkCacheEntry { 131 /// The directory entry which should be used for the cached framework. 132 const DirectoryEntry *Directory; 133 134 /// Whether this framework has been "user-specified" to be treated as if it 135 /// were a system framework (even if it was found outside a system framework 136 /// directory). 137 bool IsUserSpecifiedSystemFramework; 138 }; 139 140 /// \brief Header-search options used to initialize this header search. 141 IntrusiveRefCntPtr<HeaderSearchOptions> HSOpts; 142 143 FileManager &FileMgr; 144 /// \#include search path information. Requests for \#include "x" search the 145 /// directory of the \#including file first, then each directory in SearchDirs 146 /// consecutively. Requests for <x> search the current dir first, then each 147 /// directory in SearchDirs, starting at AngledDirIdx, consecutively. If 148 /// NoCurDirSearch is true, then the check for the file in the current 149 /// directory is suppressed. 150 std::vector<DirectoryLookup> SearchDirs; 151 unsigned AngledDirIdx; 152 unsigned SystemDirIdx; 153 bool NoCurDirSearch; 154 155 /// \brief \#include prefixes for which the 'system header' property is 156 /// overridden. 157 /// 158 /// For a \#include "x" or \#include \<x> directive, the last string in this 159 /// list which is a prefix of 'x' determines whether the file is treated as 160 /// a system header. 161 std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes; 162 163 /// \brief The path to the module cache. 164 std::string ModuleCachePath; 165 166 /// \brief All of the preprocessor-specific data about files that are 167 /// included, indexed by the FileEntry's UID. 168 std::vector<HeaderFileInfo> FileInfo; 169 170 /// \brief Keeps track of each lookup performed by LookupFile. 171 /// 172 /// The first part of the value is the starting index in SearchDirs 173 /// that the cached search was performed from. If there is a hit and 174 /// this value doesn't match the current query, the cache has to be 175 /// ignored. The second value is the entry in SearchDirs that satisfied 176 /// the query. 177 llvm::StringMap<std::pair<unsigned, unsigned>, llvm::BumpPtrAllocator> 178 LookupFileCache; 179 180 /// \brief Collection mapping a framework or subframework 181 /// name like "Carbon" to the Carbon.framework directory. 182 llvm::StringMap<FrameworkCacheEntry, llvm::BumpPtrAllocator> FrameworkMap; 183 184 /// IncludeAliases - maps include file names (including the quotes or 185 /// angle brackets) to other include file names. This is used to support the 186 /// include_alias pragma for Microsoft compatibility. 187 typedef llvm::StringMap<std::string, llvm::BumpPtrAllocator> 188 IncludeAliasMap; 189 OwningPtr<IncludeAliasMap> IncludeAliases; 190 191 /// HeaderMaps - This is a mapping from FileEntry -> HeaderMap, uniquing 192 /// headermaps. This vector owns the headermap. 193 std::vector<std::pair<const FileEntry*, const HeaderMap*> > HeaderMaps; 194 195 /// \brief The mapping between modules and headers. 196 mutable ModuleMap ModMap; 197 198 /// \brief Describes whether a given directory has a module map in it. 199 llvm::DenseMap<const DirectoryEntry *, bool> DirectoryHasModuleMap; 200 201 /// \brief Uniqued set of framework names, which is used to track which 202 /// headers were included as framework headers. 203 llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames; 204 205 /// \brief Entity used to resolve the identifier IDs of controlling 206 /// macros into IdentifierInfo pointers, as needed. 207 ExternalIdentifierLookup *ExternalLookup; 208 209 /// \brief Entity used to look up stored header file information. 210 ExternalHeaderFileInfoSource *ExternalSource; 211 212 // Various statistics we track for performance analysis. 213 unsigned NumIncluded; 214 unsigned NumMultiIncludeFileOptzn; 215 unsigned NumFrameworkLookups, NumSubFrameworkLookups; 216 217 // HeaderSearch doesn't support default or copy construction. 218 HeaderSearch(const HeaderSearch&) LLVM_DELETED_FUNCTION; 219 void operator=(const HeaderSearch&) LLVM_DELETED_FUNCTION; 220 221 friend class DirectoryLookup; 222 223 public: 224 HeaderSearch(IntrusiveRefCntPtr<HeaderSearchOptions> HSOpts, 225 FileManager &FM, DiagnosticsEngine &Diags, 226 const LangOptions &LangOpts, const TargetInfo *Target); 227 ~HeaderSearch(); 228 229 /// \brief Retrieve the header-search options with which this header search 230 /// was initialized. 231 HeaderSearchOptions &getHeaderSearchOpts() const { return *HSOpts; } 232 233 FileManager &getFileMgr() const { return FileMgr; } 234 235 /// \brief Interface for setting the file search paths. 236 void SetSearchPaths(const std::vector<DirectoryLookup> &dirs, 237 unsigned angledDirIdx, unsigned systemDirIdx, 238 bool noCurDirSearch) { 239 assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() && 240 "Directory indicies are unordered"); 241 SearchDirs = dirs; 242 AngledDirIdx = angledDirIdx; 243 SystemDirIdx = systemDirIdx; 244 NoCurDirSearch = noCurDirSearch; 245 //LookupFileCache.clear(); 246 } 247 248 /// \brief Add an additional search path. 249 void AddSearchPath(const DirectoryLookup &dir, bool isAngled) { 250 unsigned idx = isAngled ? SystemDirIdx : AngledDirIdx; 251 SearchDirs.insert(SearchDirs.begin() + idx, dir); 252 if (!isAngled) 253 AngledDirIdx++; 254 SystemDirIdx++; 255 } 256 257 /// \brief Set the list of system header prefixes. 258 void SetSystemHeaderPrefixes(ArrayRef<std::pair<std::string, bool> > P) { 259 SystemHeaderPrefixes.assign(P.begin(), P.end()); 260 } 261 262 /// \brief Checks whether the map exists or not. 263 bool HasIncludeAliasMap() const { 264 return IncludeAliases; 265 } 266 267 /// \brief Map the source include name to the dest include name. 268 /// 269 /// The Source should include the angle brackets or quotes, the dest 270 /// should not. This allows for distinction between <> and "" headers. 271 void AddIncludeAlias(StringRef Source, StringRef Dest) { 272 if (!IncludeAliases) 273 IncludeAliases.reset(new IncludeAliasMap); 274 (*IncludeAliases)[Source] = Dest; 275 } 276 277 /// MapHeaderToIncludeAlias - Maps one header file name to a different header 278 /// file name, for use with the include_alias pragma. Note that the source 279 /// file name should include the angle brackets or quotes. Returns StringRef 280 /// as null if the header cannot be mapped. 281 StringRef MapHeaderToIncludeAlias(StringRef Source) { 282 assert(IncludeAliases && "Trying to map headers when there's no map"); 283 284 // Do any filename replacements before anything else 285 IncludeAliasMap::const_iterator Iter = IncludeAliases->find(Source); 286 if (Iter != IncludeAliases->end()) 287 return Iter->second; 288 return StringRef(); 289 } 290 291 /// \brief Set the path to the module cache. 292 void setModuleCachePath(StringRef CachePath) { 293 ModuleCachePath = CachePath; 294 } 295 296 /// \brief Retrieve the path to the module cache. 297 StringRef getModuleCachePath() const { return ModuleCachePath; } 298 299 /// \brief Consider modules when including files from this directory. 300 void setDirectoryHasModuleMap(const DirectoryEntry* Dir) { 301 DirectoryHasModuleMap[Dir] = true; 302 } 303 304 /// \brief Forget everything we know about headers so far. 305 void ClearFileInfo() { 306 FileInfo.clear(); 307 } 308 309 void SetExternalLookup(ExternalIdentifierLookup *EIL) { 310 ExternalLookup = EIL; 311 } 312 313 ExternalIdentifierLookup *getExternalLookup() const { 314 return ExternalLookup; 315 } 316 317 /// \brief Set the external source of header information. 318 void SetExternalSource(ExternalHeaderFileInfoSource *ES) { 319 ExternalSource = ES; 320 } 321 322 /// \brief Set the target information for the header search, if not 323 /// already known. 324 void setTarget(const TargetInfo &Target); 325 326 /// \brief Given a "foo" or \<foo> reference, look up the indicated file, 327 /// return null on failure. 328 /// 329 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member 330 /// the file was found in, or null if not applicable. 331 /// 332 /// \param isAngled indicates whether the file reference is a <> reference. 333 /// 334 /// \param CurDir If non-null, the file was found in the specified directory 335 /// search location. This is used to implement \#include_next. 336 /// 337 /// \param CurFileEnt If non-null, indicates where the \#including file is, in 338 /// case a relative search is needed. 339 /// 340 /// \param SearchPath If non-null, will be set to the search path relative 341 /// to which the file was found. If the include path is absolute, SearchPath 342 /// will be set to an empty string. 343 /// 344 /// \param RelativePath If non-null, will be set to the path relative to 345 /// SearchPath at which the file was found. This only differs from the 346 /// Filename for framework includes. 347 /// 348 /// \param SuggestedModule If non-null, and the file found is semantically 349 /// part of a known module, this will be set to the module that should 350 /// be imported instead of preprocessing/parsing the file found. 351 const FileEntry *LookupFile(StringRef Filename, bool isAngled, 352 const DirectoryLookup *FromDir, 353 const DirectoryLookup *&CurDir, 354 const FileEntry *CurFileEnt, 355 SmallVectorImpl<char> *SearchPath, 356 SmallVectorImpl<char> *RelativePath, 357 Module **SuggestedModule, 358 bool SkipCache = false); 359 360 /// \brief Look up a subframework for the specified \#include file. 361 /// 362 /// For example, if \#include'ing <HIToolbox/HIToolbox.h> from 363 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if 364 /// HIToolbox is a subframework within Carbon.framework. If so, return 365 /// the FileEntry for the designated file, otherwise return null. 366 const FileEntry *LookupSubframeworkHeader( 367 StringRef Filename, 368 const FileEntry *RelativeFileEnt, 369 SmallVectorImpl<char> *SearchPath, 370 SmallVectorImpl<char> *RelativePath, 371 Module **SuggestedModule); 372 373 /// \brief Look up the specified framework name in our framework cache. 374 /// \returns The DirectoryEntry it is in if we know, null otherwise. 375 FrameworkCacheEntry &LookupFrameworkCache(StringRef FWName) { 376 return FrameworkMap.GetOrCreateValue(FWName).getValue(); 377 } 378 379 /// \brief Mark the specified file as a target of of a \#include, 380 /// \#include_next, or \#import directive. 381 /// 382 /// \return false if \#including the file will have no effect or true 383 /// if we should include it. 384 bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport); 385 386 387 /// \brief Return whether the specified file is a normal header, 388 /// a system header, or a C++ friendly system header. 389 SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) { 390 return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo; 391 } 392 393 /// \brief Mark the specified file as a "once only" file, e.g. due to 394 /// \#pragma once. 395 void MarkFileIncludeOnce(const FileEntry *File) { 396 HeaderFileInfo &FI = getFileInfo(File); 397 FI.isImport = true; 398 FI.isPragmaOnce = true; 399 } 400 401 /// \brief Mark the specified file as a system header, e.g. due to 402 /// \#pragma GCC system_header. 403 void MarkFileSystemHeader(const FileEntry *File) { 404 getFileInfo(File).DirInfo = SrcMgr::C_System; 405 } 406 407 /// \brief Mark the specified file as part of a module. 408 void MarkFileModuleHeader(const FileEntry *File); 409 410 /// \brief Increment the count for the number of times the specified 411 /// FileEntry has been entered. 412 void IncrementIncludeCount(const FileEntry *File) { 413 ++getFileInfo(File).NumIncludes; 414 } 415 416 /// \brief Mark the specified file as having a controlling macro. 417 /// 418 /// This is used by the multiple-include optimization to eliminate 419 /// no-op \#includes. 420 void SetFileControllingMacro(const FileEntry *File, 421 const IdentifierInfo *ControllingMacro) { 422 getFileInfo(File).ControllingMacro = ControllingMacro; 423 } 424 425 /// \brief Determine whether this file is intended to be safe from 426 /// multiple inclusions, e.g., it has \#pragma once or a controlling 427 /// macro. 428 /// 429 /// This routine does not consider the effect of \#import 430 bool isFileMultipleIncludeGuarded(const FileEntry *File); 431 432 /// CreateHeaderMap - This method returns a HeaderMap for the specified 433 /// FileEntry, uniquing them through the 'HeaderMaps' datastructure. 434 const HeaderMap *CreateHeaderMap(const FileEntry *FE); 435 436 /// \brief Retrieve the name of the module file that should be used to 437 /// load the given module. 438 /// 439 /// \param Module The module whose module file name will be returned. 440 /// 441 /// \returns The name of the module file that corresponds to this module, 442 /// or an empty string if this module does not correspond to any module file. 443 std::string getModuleFileName(Module *Module); 444 445 /// \brief Retrieve the name of the module file that should be used to 446 /// load a module with the given name. 447 /// 448 /// \param ModuleName The module whose module file name will be returned. 449 /// 450 /// \returns The name of the module file that corresponds to this module, 451 /// or an empty string if this module does not correspond to any module file. 452 std::string getModuleFileName(StringRef ModuleName); 453 454 /// \brief Lookup a module Search for a module with the given name. 455 /// 456 /// \param ModuleName The name of the module we're looking for. 457 /// 458 /// \param AllowSearch Whether we are allowed to search in the various 459 /// search directories to produce a module definition. If not, this lookup 460 /// will only return an already-known module. 461 /// 462 /// \returns The module with the given name. 463 Module *lookupModule(StringRef ModuleName, bool AllowSearch = true); 464 465 void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; } 466 467 /// \brief Determine whether there is a module map that may map the header 468 /// with the given file name to a (sub)module. 469 /// 470 /// \param Filename The name of the file. 471 /// 472 /// \param Root The "root" directory, at which we should stop looking for 473 /// module maps. 474 bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root); 475 476 /// \brief Retrieve the module that corresponds to the given file, if any. 477 /// 478 /// \param File The header that we wish to map to a module. 479 Module *findModuleForHeader(const FileEntry *File) const; 480 481 /// \brief Read the contents of the given module map file. 482 /// 483 /// \param File The module map file. 484 /// 485 /// \returns true if an error occurred, false otherwise. 486 bool loadModuleMapFile(const FileEntry *File); 487 488 /// \brief Collect the set of all known, top-level modules. 489 /// 490 /// \param Modules Will be filled with the set of known, top-level modules. 491 void collectAllModules(SmallVectorImpl<Module *> &Modules); 492 493 private: 494 /// \brief Retrieve a module with the given name, which may be part of the 495 /// given framework. 496 /// 497 /// \param Name The name of the module to retrieve. 498 /// 499 /// \param Dir The framework directory (e.g., ModuleName.framework). 500 /// 501 /// \param IsSystem Whether the framework directory is part of the system 502 /// frameworks. 503 /// 504 /// \returns The module, if found; otherwise, null. 505 Module *loadFrameworkModule(StringRef Name, 506 const DirectoryEntry *Dir, 507 bool IsSystem); 508 509 public: 510 /// \brief Retrieve the module map. 511 ModuleMap &getModuleMap() { return ModMap; } 512 513 unsigned header_file_size() const { return FileInfo.size(); } 514 515 // Used by ASTReader. 516 void setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID); 517 518 /// \brief Return the HeaderFileInfo structure for the specified FileEntry. 519 const HeaderFileInfo &getFileInfo(const FileEntry *FE) const { 520 return const_cast<HeaderSearch*>(this)->getFileInfo(FE); 521 } 522 523 // Used by external tools 524 typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator; 525 search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); } 526 search_dir_iterator search_dir_end() const { return SearchDirs.end(); } 527 unsigned search_dir_size() const { return SearchDirs.size(); } 528 529 search_dir_iterator quoted_dir_begin() const { 530 return SearchDirs.begin(); 531 } 532 search_dir_iterator quoted_dir_end() const { 533 return SearchDirs.begin() + AngledDirIdx; 534 } 535 536 search_dir_iterator angled_dir_begin() const { 537 return SearchDirs.begin() + AngledDirIdx; 538 } 539 search_dir_iterator angled_dir_end() const { 540 return SearchDirs.begin() + SystemDirIdx; 541 } 542 543 search_dir_iterator system_dir_begin() const { 544 return SearchDirs.begin() + SystemDirIdx; 545 } 546 search_dir_iterator system_dir_end() const { return SearchDirs.end(); } 547 548 /// \brief Retrieve a uniqued framework name. 549 StringRef getUniqueFrameworkName(StringRef Framework); 550 551 void PrintStats(); 552 553 size_t getTotalMemory() const; 554 555 static std::string NormalizeDashIncludePath(StringRef File, 556 FileManager &FileMgr); 557 558 private: 559 /// \brief Describes what happened when we tried to load a module map file. 560 enum LoadModuleMapResult { 561 /// \brief The module map file had already been loaded. 562 LMM_AlreadyLoaded, 563 /// \brief The module map file was loaded by this invocation. 564 LMM_NewlyLoaded, 565 /// \brief There is was directory with the given name. 566 LMM_NoDirectory, 567 /// \brief There was either no module map file or the module map file was 568 /// invalid. 569 LMM_InvalidModuleMap 570 }; 571 572 /// \brief Try to load the module map file in the given directory. 573 /// 574 /// \param DirName The name of the directory where we will look for a module 575 /// map file. 576 /// 577 /// \returns The result of attempting to load the module map file from the 578 /// named directory. 579 LoadModuleMapResult loadModuleMapFile(StringRef DirName); 580 581 /// \brief Try to load the module map file in the given directory. 582 /// 583 /// \param Dir The directory where we will look for a module map file. 584 /// 585 /// \returns The result of attempting to load the module map file from the 586 /// named directory. 587 LoadModuleMapResult loadModuleMapFile(const DirectoryEntry *Dir); 588 589 /// \brief Return the HeaderFileInfo structure for the specified FileEntry. 590 HeaderFileInfo &getFileInfo(const FileEntry *FE); 591 }; 592 593 } // end namespace clang 594 595 #endif 596