HeaderSearch.h revision cf70d7873fe3098bdac72e7628f4e832d14d5143
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 /// \brief Set the path to the module cache and the name of the module 211 /// we're building 212 void configureModules(StringRef CachePath, StringRef BuildingModule) { 213 ModuleCachePath = CachePath; 214 this->BuildingModule = BuildingModule; 215 } 216 217 /// ClearFileInfo - Forget everything we know about headers so far. 218 void ClearFileInfo() { 219 FileInfo.clear(); 220 } 221 222 void SetExternalLookup(ExternalIdentifierLookup *EIL) { 223 ExternalLookup = EIL; 224 } 225 226 ExternalIdentifierLookup *getExternalLookup() const { 227 return ExternalLookup; 228 } 229 230 /// \brief Set the external source of header information. 231 void SetExternalSource(ExternalHeaderFileInfoSource *ES) { 232 ExternalSource = ES; 233 } 234 235 /// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 236 /// return null on failure. 237 /// 238 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member 239 /// the file was found in, or null if not applicable. 240 /// 241 /// \param isAngled indicates whether the file reference is a <> reference. 242 /// 243 /// \param CurDir If non-null, the file was found in the specified directory 244 /// search location. This is used to implement #include_next. 245 /// 246 /// \param CurFileEnt If non-null, indicates where the #including file is, in 247 /// case a relative search is needed. 248 /// 249 /// \param SearchPath If non-null, will be set to the search path relative 250 /// to which the file was found. If the include path is absolute, SearchPath 251 /// will be set to an empty string. 252 /// 253 /// \param RelativePath If non-null, will be set to the path relative to 254 /// SearchPath at which the file was found. This only differs from the 255 /// Filename for framework includes. 256 /// 257 /// \param SuggestedModule If non-null, and the file found is semantically 258 /// part of a known module, this will be set to the name of the module that 259 /// could be imported instead of preprocessing/parsing the file found. 260 const FileEntry *LookupFile(StringRef Filename, bool isAngled, 261 const DirectoryLookup *FromDir, 262 const DirectoryLookup *&CurDir, 263 const FileEntry *CurFileEnt, 264 SmallVectorImpl<char> *SearchPath, 265 SmallVectorImpl<char> *RelativePath, 266 StringRef *SuggestedModule); 267 268 /// LookupSubframeworkHeader - Look up a subframework for the specified 269 /// #include file. For example, if #include'ing <HIToolbox/HIToolbox.h> from 270 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox 271 /// is a subframework within Carbon.framework. If so, return the FileEntry 272 /// for the designated file, otherwise return null. 273 const FileEntry *LookupSubframeworkHeader( 274 StringRef Filename, 275 const FileEntry *RelativeFileEnt, 276 SmallVectorImpl<char> *SearchPath, 277 SmallVectorImpl<char> *RelativePath); 278 279 /// LookupFrameworkCache - Look up the specified framework name in our 280 /// framework cache, returning the DirectoryEntry it is in if we know, 281 /// otherwise, return null. 282 const DirectoryEntry *&LookupFrameworkCache(StringRef FWName) { 283 return FrameworkMap.GetOrCreateValue(FWName).getValue(); 284 } 285 286 /// ShouldEnterIncludeFile - Mark the specified file as a target of of a 287 /// #include, #include_next, or #import directive. Return false if #including 288 /// the file will have no effect or true if we should include it. 289 bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport); 290 291 292 /// getFileDirFlavor - Return whether the specified file is a normal header, 293 /// a system header, or a C++ friendly system header. 294 SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) { 295 return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo; 296 } 297 298 /// MarkFileIncludeOnce - Mark the specified file as a "once only" file, e.g. 299 /// due to #pragma once. 300 void MarkFileIncludeOnce(const FileEntry *File) { 301 HeaderFileInfo &FI = getFileInfo(File); 302 FI.isImport = true; 303 FI.isPragmaOnce = true; 304 } 305 306 /// MarkFileSystemHeader - Mark the specified file as a system header, e.g. 307 /// due to #pragma GCC system_header. 308 void MarkFileSystemHeader(const FileEntry *File) { 309 getFileInfo(File).DirInfo = SrcMgr::C_System; 310 } 311 312 /// IncrementIncludeCount - Increment the count for the number of times the 313 /// specified FileEntry has been entered. 314 void IncrementIncludeCount(const FileEntry *File) { 315 ++getFileInfo(File).NumIncludes; 316 } 317 318 /// SetFileControllingMacro - Mark the specified file as having a controlling 319 /// macro. This is used by the multiple-include optimization to eliminate 320 /// no-op #includes. 321 void SetFileControllingMacro(const FileEntry *File, 322 const IdentifierInfo *ControllingMacro) { 323 getFileInfo(File).ControllingMacro = ControllingMacro; 324 } 325 326 /// \brief Determine whether this file is intended to be safe from 327 /// multiple inclusions, e.g., it has #pragma once or a controlling 328 /// macro. 329 /// 330 /// This routine does not consider the effect of #import 331 bool isFileMultipleIncludeGuarded(const FileEntry *File); 332 333 /// CreateHeaderMap - This method returns a HeaderMap for the specified 334 /// FileEntry, uniquing them through the the 'HeaderMaps' datastructure. 335 const HeaderMap *CreateHeaderMap(const FileEntry *FE); 336 337 /// \brief Search in the module cache path for a module with the given 338 /// name. 339 /// 340 /// \param If non-NULL, will be set to the module file name we expected to 341 /// find (regardless of whether it was actually found or not). 342 /// 343 /// \param UmbrellaHeader If non-NULL, and no module was found in the module 344 /// cache, this routine will search in the framework paths to determine 345 /// whether a module can be built from an umbrella header. If so, the pointee 346 /// will be set to the path of the umbrella header. 347 /// 348 /// \returns A file describing the named module, if available, or NULL to 349 /// indicate that the module could not be found. 350 const FileEntry *lookupModule(StringRef ModuleName, 351 std::string *ModuleFileName = 0, 352 std::string *UmbrellaHeader = 0); 353 354 void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; } 355 356 /// \brief Determine whether there is a module map that may map the header 357 /// with the given file name to a (sub)module. 358 /// 359 /// \param Filename The name of the file. 360 /// 361 /// \param Root The "root" directory, at which we should stop looking for 362 /// module maps. 363 bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root); 364 365 /// \brief Retrieve the module that corresponds to the given file, if any. 366 /// 367 /// FIXME: This will need to be generalized for submodules. 368 StringRef findModuleForHeader(const FileEntry *File); 369 370 typedef std::vector<HeaderFileInfo>::const_iterator header_file_iterator; 371 header_file_iterator header_file_begin() const { return FileInfo.begin(); } 372 header_file_iterator header_file_end() const { return FileInfo.end(); } 373 unsigned header_file_size() const { return FileInfo.size(); } 374 375 // Used by ASTReader. 376 void setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID); 377 378 // Used by external tools 379 typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator; 380 search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); } 381 search_dir_iterator search_dir_end() const { return SearchDirs.end(); } 382 unsigned search_dir_size() const { return SearchDirs.size(); } 383 384 search_dir_iterator quoted_dir_begin() const { 385 return SearchDirs.begin(); 386 } 387 search_dir_iterator quoted_dir_end() const { 388 return SearchDirs.begin() + AngledDirIdx; 389 } 390 391 search_dir_iterator angled_dir_begin() const { 392 return SearchDirs.begin() + AngledDirIdx; 393 } 394 search_dir_iterator angled_dir_end() const { 395 return SearchDirs.begin() + SystemDirIdx; 396 } 397 398 search_dir_iterator system_dir_begin() const { 399 return SearchDirs.begin() + SystemDirIdx; 400 } 401 search_dir_iterator system_dir_end() const { return SearchDirs.end(); } 402 403 /// \brief Retrieve a uniqued framework name. 404 StringRef getUniqueFrameworkName(StringRef Framework); 405 406 void PrintStats(); 407 408 size_t getTotalMemory() const; 409 410private: 411 /// \brief Try to load the module map file in the given directory. 412 /// 413 /// \returns false if the module map was loaded successfully, true otherwise. 414 bool loadModuleMapFile(StringRef DirName); 415 416 /// \brief Try to load the module map file in the given directory. 417 /// 418 /// \returns false if the module map was loaded successfully, true otherwise. 419 bool loadModuleMapFile(const DirectoryEntry *Dir); 420 421 /// getFileInfo - Return the HeaderFileInfo structure for the specified 422 /// FileEntry. 423 HeaderFileInfo &getFileInfo(const FileEntry *FE); 424}; 425 426} // end namespace clang 427 428#endif 429