HeaderSearch.h revision 6e975c4517958bcc11c834336d340797356058db
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 /// \brief The path to the module cache. 133 std::string ModuleCachePath; 134 135 /// FileInfo - This contains all of the preprocessor-specific data about files 136 /// that are included. The vector is indexed by the FileEntry's UID. 137 /// 138 std::vector<HeaderFileInfo> FileInfo; 139 140 /// LookupFileCache - This is keeps track of each lookup performed by 141 /// LookupFile. The first part of the value is the starting index in 142 /// SearchDirs that the cached search was performed from. If there is a hit 143 /// and this value doesn't match the current query, the cache has to be 144 /// ignored. The second value is the entry in SearchDirs that satisfied the 145 /// query. 146 llvm::StringMap<std::pair<unsigned, unsigned>, llvm::BumpPtrAllocator> 147 LookupFileCache; 148 149 150 /// FrameworkMap - This is a collection mapping a framework or subframework 151 /// name like "Carbon" to the Carbon.framework directory. 152 llvm::StringMap<const DirectoryEntry *, llvm::BumpPtrAllocator> 153 FrameworkMap; 154 155 /// HeaderMaps - This is a mapping from FileEntry -> HeaderMap, uniquing 156 /// headermaps. This vector owns the headermap. 157 std::vector<std::pair<const FileEntry*, const HeaderMap*> > HeaderMaps; 158 159 /// \brief Uniqued set of framework names, which is used to track which 160 /// headers were included as framework headers. 161 llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames; 162 163 /// \brief Entity used to resolve the identifier IDs of controlling 164 /// macros into IdentifierInfo pointers, as needed. 165 ExternalIdentifierLookup *ExternalLookup; 166 167 /// \brief Entity used to look up stored header file information. 168 ExternalHeaderFileInfoSource *ExternalSource; 169 170 // Various statistics we track for performance analysis. 171 unsigned NumIncluded; 172 unsigned NumMultiIncludeFileOptzn; 173 unsigned NumFrameworkLookups, NumSubFrameworkLookups; 174 175 // HeaderSearch doesn't support default or copy construction. 176 explicit HeaderSearch(); 177 explicit HeaderSearch(const HeaderSearch&); 178 void operator=(const HeaderSearch&); 179public: 180 HeaderSearch(FileManager &FM); 181 ~HeaderSearch(); 182 183 FileManager &getFileMgr() const { return FileMgr; } 184 185 /// SetSearchPaths - Interface for setting the file search paths. 186 /// 187 void SetSearchPaths(const std::vector<DirectoryLookup> &dirs, 188 unsigned angledDirIdx, unsigned systemDirIdx, 189 bool noCurDirSearch) { 190 assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() && 191 "Directory indicies are unordered"); 192 SearchDirs = dirs; 193 AngledDirIdx = angledDirIdx; 194 SystemDirIdx = systemDirIdx; 195 NoCurDirSearch = noCurDirSearch; 196 //LookupFileCache.clear(); 197 } 198 199 /// \brief Set the path to the module cache. 200 void setModuleCachePath(StringRef Path) { 201 ModuleCachePath = Path; 202 } 203 204 /// ClearFileInfo - Forget everything we know about headers so far. 205 void ClearFileInfo() { 206 FileInfo.clear(); 207 } 208 209 void SetExternalLookup(ExternalIdentifierLookup *EIL) { 210 ExternalLookup = EIL; 211 } 212 213 ExternalIdentifierLookup *getExternalLookup() const { 214 return ExternalLookup; 215 } 216 217 /// \brief Set the external source of header information. 218 void SetExternalSource(ExternalHeaderFileInfoSource *ES) { 219 ExternalSource = ES; 220 } 221 222 /// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 223 /// return null on failure. 224 /// 225 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member 226 /// the file was found in, or null if not applicable. 227 /// 228 /// \param isAngled indicates whether the file reference is a <> reference. 229 /// 230 /// \param CurDir If non-null, the file was found in the specified directory 231 /// search location. This is used to implement #include_next. 232 /// 233 /// \param CurFileEnt If non-null, indicates where the #including file is, in 234 /// case a relative search is needed. 235 /// 236 /// \param SearchPath If non-null, will be set to the search path relative 237 /// to which the file was found. If the include path is absolute, SearchPath 238 /// will be set to an empty string. 239 /// 240 /// \param RelativePath If non-null, will be set to the path relative to 241 /// SearchPath at which the file was found. This only differs from the 242 /// Filename for framework includes. 243 const FileEntry *LookupFile(StringRef Filename, bool isAngled, 244 const DirectoryLookup *FromDir, 245 const DirectoryLookup *&CurDir, 246 const FileEntry *CurFileEnt, 247 SmallVectorImpl<char> *SearchPath, 248 SmallVectorImpl<char> *RelativePath); 249 250 /// LookupSubframeworkHeader - Look up a subframework for the specified 251 /// #include file. For example, if #include'ing <HIToolbox/HIToolbox.h> from 252 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox 253 /// is a subframework within Carbon.framework. If so, return the FileEntry 254 /// for the designated file, otherwise return null. 255 const FileEntry *LookupSubframeworkHeader( 256 StringRef Filename, 257 const FileEntry *RelativeFileEnt, 258 SmallVectorImpl<char> *SearchPath, 259 SmallVectorImpl<char> *RelativePath); 260 261 /// LookupFrameworkCache - Look up the specified framework name in our 262 /// framework cache, returning the DirectoryEntry it is in if we know, 263 /// otherwise, return null. 264 const DirectoryEntry *&LookupFrameworkCache(StringRef FWName) { 265 return FrameworkMap.GetOrCreateValue(FWName).getValue(); 266 } 267 268 /// ShouldEnterIncludeFile - Mark the specified file as a target of of a 269 /// #include, #include_next, or #import directive. Return false if #including 270 /// the file will have no effect or true if we should include it. 271 bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport); 272 273 274 /// getFileDirFlavor - Return whether the specified file is a normal header, 275 /// a system header, or a C++ friendly system header. 276 SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) { 277 return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo; 278 } 279 280 /// MarkFileIncludeOnce - Mark the specified file as a "once only" file, e.g. 281 /// due to #pragma once. 282 void MarkFileIncludeOnce(const FileEntry *File) { 283 HeaderFileInfo &FI = getFileInfo(File); 284 FI.isImport = true; 285 FI.isPragmaOnce = true; 286 } 287 288 /// MarkFileSystemHeader - Mark the specified file as a system header, e.g. 289 /// due to #pragma GCC system_header. 290 void MarkFileSystemHeader(const FileEntry *File) { 291 getFileInfo(File).DirInfo = SrcMgr::C_System; 292 } 293 294 /// IncrementIncludeCount - Increment the count for the number of times the 295 /// specified FileEntry has been entered. 296 void IncrementIncludeCount(const FileEntry *File) { 297 ++getFileInfo(File).NumIncludes; 298 } 299 300 /// SetFileControllingMacro - Mark the specified file as having a controlling 301 /// macro. This is used by the multiple-include optimization to eliminate 302 /// no-op #includes. 303 void SetFileControllingMacro(const FileEntry *File, 304 const IdentifierInfo *ControllingMacro) { 305 getFileInfo(File).ControllingMacro = ControllingMacro; 306 } 307 308 /// \brief Determine whether this file is intended to be safe from 309 /// multiple inclusions, e.g., it has #pragma once or a controlling 310 /// macro. 311 /// 312 /// This routine does not consider the effect of #import 313 bool isFileMultipleIncludeGuarded(const FileEntry *File); 314 315 /// CreateHeaderMap - This method returns a HeaderMap for the specified 316 /// FileEntry, uniquing them through the the 'HeaderMaps' datastructure. 317 const HeaderMap *CreateHeaderMap(const FileEntry *FE); 318 319 /// \brief Search in the module cache path for a module with the given 320 /// name. 321 /// 322 /// \param If non-NULL, will be set to the module file name we expected to 323 /// find (regardless of whether it was actually found or not). 324 /// 325 /// \param UmbrellaHeader If non-NULL, and no module was found in the module 326 /// cache, this routine will search in the framework paths to determine 327 /// whether a module can be built from an umbrella header. If so, the pointee 328 /// will be set to the path of the umbrella header. 329 /// 330 /// \returns A file describing the named module, if available, or NULL to 331 /// indicate that the module could not be found. 332 const FileEntry *lookupModule(StringRef ModuleName, 333 std::string *ModuleFileName = 0, 334 std::string *UmbrellaHeader = 0); 335 336 void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; } 337 338 typedef std::vector<HeaderFileInfo>::const_iterator header_file_iterator; 339 header_file_iterator header_file_begin() const { return FileInfo.begin(); } 340 header_file_iterator header_file_end() const { return FileInfo.end(); } 341 unsigned header_file_size() const { return FileInfo.size(); } 342 343 // Used by ASTReader. 344 void setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID); 345 346 // Used by external tools 347 typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator; 348 search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); } 349 search_dir_iterator search_dir_end() const { return SearchDirs.end(); } 350 unsigned search_dir_size() const { return SearchDirs.size(); } 351 352 search_dir_iterator quoted_dir_begin() const { 353 return SearchDirs.begin(); 354 } 355 search_dir_iterator quoted_dir_end() const { 356 return SearchDirs.begin() + AngledDirIdx; 357 } 358 359 search_dir_iterator angled_dir_begin() const { 360 return SearchDirs.begin() + AngledDirIdx; 361 } 362 search_dir_iterator angled_dir_end() const { 363 return SearchDirs.begin() + SystemDirIdx; 364 } 365 366 search_dir_iterator system_dir_begin() const { 367 return SearchDirs.begin() + SystemDirIdx; 368 } 369 search_dir_iterator system_dir_end() const { return SearchDirs.end(); } 370 371 /// \brief Retrieve a uniqued framework name. 372 StringRef getUniqueFrameworkName(StringRef Framework); 373 374 void PrintStats(); 375 376 size_t getTotalMemory() const; 377 378private: 379 380 /// getFileInfo - Return the HeaderFileInfo structure for the specified 381 /// FileEntry. 382 HeaderFileInfo &getFileInfo(const FileEntry *FE); 383}; 384 385} // end namespace clang 386 387#endif 388