clang  9.0.0svn
HeaderSearch.h
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1 //===- HeaderSearch.h - Resolve Header File Locations -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the HeaderSearch interface.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LEX_HEADERSEARCH_H
14 #define LLVM_CLANG_LEX_HEADERSEARCH_H
15 
19 #include "clang/Lex/HeaderMap.h"
20 #include "clang/Lex/ModuleMap.h"
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/ADT/StringMap.h"
24 #include "llvm/ADT/StringSet.h"
25 #include "llvm/ADT/StringRef.h"
26 #include "llvm/Support/Allocator.h"
27 #include <cassert>
28 #include <cstddef>
29 #include <memory>
30 #include <string>
31 #include <utility>
32 #include <vector>
33 
34 namespace clang {
35 
36 class DiagnosticsEngine;
37 class DirectoryEntry;
38 class ExternalPreprocessorSource;
39 class FileEntry;
40 class FileManager;
41 class HeaderSearchOptions;
42 class IdentifierInfo;
43 class LangOptions;
44 class Module;
45 class Preprocessor;
46 class TargetInfo;
47 
48 /// The preprocessor keeps track of this information for each
49 /// file that is \#included.
51  /// True if this is a \#import'd or \#pragma once file.
52  unsigned isImport : 1;
53 
54  /// True if this is a \#pragma once file.
55  unsigned isPragmaOnce : 1;
56 
57  /// Keep track of whether this is a system header, and if so,
58  /// whether it is C++ clean or not. This can be set by the include paths or
59  /// by \#pragma gcc system_header. This is an instance of
60  /// SrcMgr::CharacteristicKind.
61  unsigned DirInfo : 3;
62 
63  /// Whether this header file info was supplied by an external source,
64  /// and has not changed since.
65  unsigned External : 1;
66 
67  /// Whether this header is part of a module.
68  unsigned isModuleHeader : 1;
69 
70  /// Whether this header is part of the module that we are building.
72 
73  /// Whether this structure is considered to already have been
74  /// "resolved", meaning that it was loaded from the external source.
75  unsigned Resolved : 1;
76 
77  /// Whether this is a header inside a framework that is currently
78  /// being built.
79  ///
80  /// When a framework is being built, the headers have not yet been placed
81  /// into the appropriate framework subdirectories, and therefore are
82  /// provided via a header map. This bit indicates when this is one of
83  /// those framework headers.
84  unsigned IndexHeaderMapHeader : 1;
85 
86  /// Whether this file has been looked up as a header.
87  unsigned IsValid : 1;
88 
89  /// The number of times the file has been included already.
90  unsigned short NumIncludes = 0;
91 
92  /// The ID number of the controlling macro.
93  ///
94  /// This ID number will be non-zero when there is a controlling
95  /// macro whose IdentifierInfo may not yet have been loaded from
96  /// external storage.
97  unsigned ControllingMacroID = 0;
98 
99  /// If this file has a \#ifndef XXX (or equivalent) guard that
100  /// protects the entire contents of the file, this is the identifier
101  /// for the macro that controls whether or not it has any effect.
102  ///
103  /// Note: Most clients should use getControllingMacro() to access
104  /// the controlling macro of this header, since
105  /// getControllingMacro() is able to load a controlling macro from
106  /// external storage.
108 
109  /// If this header came from a framework include, this is the name
110  /// of the framework.
111  StringRef Framework;
112 
117 
118  /// Retrieve the controlling macro for this header file, if
119  /// any.
120  const IdentifierInfo *
122 
123  /// Determine whether this is a non-default header file info, e.g.,
124  /// it corresponds to an actual header we've included or tried to include.
125  bool isNonDefault() const {
126  return isImport || isPragmaOnce || NumIncludes || ControllingMacro ||
128  }
129 };
130 
131 /// An external source of header file information, which may supply
132 /// information about header files already included.
134 public:
135  virtual ~ExternalHeaderFileInfoSource();
136 
137  /// Retrieve the header file information for the given file entry.
138  ///
139  /// \returns Header file information for the given file entry, with the
140  /// \c External bit set. If the file entry is not known, return a
141  /// default-constructed \c HeaderFileInfo.
142  virtual HeaderFileInfo GetHeaderFileInfo(const FileEntry *FE) = 0;
143 };
144 
145 /// This structure is used to record entries in our framework cache.
147  /// The directory entry which should be used for the cached framework.
149 
150  /// Whether this framework has been "user-specified" to be treated as if it
151  /// were a system framework (even if it was found outside a system framework
152  /// directory).
154 };
155 
156 /// Encapsulates the information needed to find the file referenced
157 /// by a \#include or \#include_next, (sub-)framework lookup, etc.
159  friend class DirectoryLookup;
160 
161  /// Header-search options used to initialize this header search.
162  std::shared_ptr<HeaderSearchOptions> HSOpts;
163 
164  DiagnosticsEngine &Diags;
165  FileManager &FileMgr;
166 
167  /// \#include search path information. Requests for \#include "x" search the
168  /// directory of the \#including file first, then each directory in SearchDirs
169  /// consecutively. Requests for <x> search the current dir first, then each
170  /// directory in SearchDirs, starting at AngledDirIdx, consecutively. If
171  /// NoCurDirSearch is true, then the check for the file in the current
172  /// directory is suppressed.
173  std::vector<DirectoryLookup> SearchDirs;
174  unsigned AngledDirIdx = 0;
175  unsigned SystemDirIdx = 0;
176  bool NoCurDirSearch = false;
177 
178  /// \#include prefixes for which the 'system header' property is
179  /// overridden.
180  ///
181  /// For a \#include "x" or \#include <x> directive, the last string in this
182  /// list which is a prefix of 'x' determines whether the file is treated as
183  /// a system header.
184  std::vector<std::pair<std::string, bool>> SystemHeaderPrefixes;
185 
186  /// The path to the module cache.
187  std::string ModuleCachePath;
188 
189  /// All of the preprocessor-specific data about files that are
190  /// included, indexed by the FileEntry's UID.
191  mutable std::vector<HeaderFileInfo> FileInfo;
192 
193  /// Keeps track of each lookup performed by LookupFile.
194  struct LookupFileCacheInfo {
195  /// Starting index in SearchDirs that the cached search was performed from.
196  /// If there is a hit and this value doesn't match the current query, the
197  /// cache has to be ignored.
198  unsigned StartIdx = 0;
199 
200  /// The entry in SearchDirs that satisfied the query.
201  unsigned HitIdx = 0;
202 
203  /// This is non-null if the original filename was mapped to a framework
204  /// include via a headermap.
205  const char *MappedName = nullptr;
206 
207  /// Default constructor -- Initialize all members with zero.
208  LookupFileCacheInfo() = default;
209 
210  void reset(unsigned StartIdx) {
211  this->StartIdx = StartIdx;
212  this->MappedName = nullptr;
213  }
214  };
215  llvm::StringMap<LookupFileCacheInfo, llvm::BumpPtrAllocator> LookupFileCache;
216 
217  /// Collection mapping a framework or subframework
218  /// name like "Carbon" to the Carbon.framework directory.
219  llvm::StringMap<FrameworkCacheEntry, llvm::BumpPtrAllocator> FrameworkMap;
220 
221  /// Maps include file names (including the quotes or
222  /// angle brackets) to other include file names. This is used to support the
223  /// include_alias pragma for Microsoft compatibility.
224  using IncludeAliasMap =
225  llvm::StringMap<std::string, llvm::BumpPtrAllocator>;
226  std::unique_ptr<IncludeAliasMap> IncludeAliases;
227 
228  /// This is a mapping from FileEntry -> HeaderMap, uniquing headermaps.
229  std::vector<std::pair<const FileEntry *, std::unique_ptr<HeaderMap>>> HeaderMaps;
230 
231  /// The mapping between modules and headers.
232  mutable ModuleMap ModMap;
233 
234  /// Describes whether a given directory has a module map in it.
235  llvm::DenseMap<const DirectoryEntry *, bool> DirectoryHasModuleMap;
236 
237  /// Set of module map files we've already loaded, and a flag indicating
238  /// whether they were valid or not.
239  llvm::DenseMap<const FileEntry *, bool> LoadedModuleMaps;
240 
241  /// Uniqued set of framework names, which is used to track which
242  /// headers were included as framework headers.
243  llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames;
244 
245  /// Entity used to resolve the identifier IDs of controlling
246  /// macros into IdentifierInfo pointers, and keep the identifire up to date,
247  /// as needed.
248  ExternalPreprocessorSource *ExternalLookup = nullptr;
249 
250  /// Entity used to look up stored header file information.
251  ExternalHeaderFileInfoSource *ExternalSource = nullptr;
252 
253  // Various statistics we track for performance analysis.
254  unsigned NumIncluded = 0;
255  unsigned NumMultiIncludeFileOptzn = 0;
256  unsigned NumFrameworkLookups = 0;
257  unsigned NumSubFrameworkLookups = 0;
258 
259 public:
260  HeaderSearch(std::shared_ptr<HeaderSearchOptions> HSOpts,
261  SourceManager &SourceMgr, DiagnosticsEngine &Diags,
262  const LangOptions &LangOpts, const TargetInfo *Target);
263  HeaderSearch(const HeaderSearch &) = delete;
264  HeaderSearch &operator=(const HeaderSearch &) = delete;
265 
266  /// Retrieve the header-search options with which this header search
267  /// was initialized.
268  HeaderSearchOptions &getHeaderSearchOpts() const { return *HSOpts; }
269 
270  FileManager &getFileMgr() const { return FileMgr; }
271 
272  DiagnosticsEngine &getDiags() const { return Diags; }
273 
274  /// Interface for setting the file search paths.
275  void SetSearchPaths(const std::vector<DirectoryLookup> &dirs,
276  unsigned angledDirIdx, unsigned systemDirIdx,
277  bool noCurDirSearch) {
278  assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() &&
279  "Directory indices are unordered");
280  SearchDirs = dirs;
281  AngledDirIdx = angledDirIdx;
282  SystemDirIdx = systemDirIdx;
283  NoCurDirSearch = noCurDirSearch;
284  //LookupFileCache.clear();
285  }
286 
287  /// Add an additional search path.
288  void AddSearchPath(const DirectoryLookup &dir, bool isAngled) {
289  unsigned idx = isAngled ? SystemDirIdx : AngledDirIdx;
290  SearchDirs.insert(SearchDirs.begin() + idx, dir);
291  if (!isAngled)
292  AngledDirIdx++;
293  SystemDirIdx++;
294  }
295 
296  /// Set the list of system header prefixes.
297  void SetSystemHeaderPrefixes(ArrayRef<std::pair<std::string, bool>> P) {
298  SystemHeaderPrefixes.assign(P.begin(), P.end());
299  }
300 
301  /// Checks whether the map exists or not.
302  bool HasIncludeAliasMap() const { return (bool)IncludeAliases; }
303 
304  /// Map the source include name to the dest include name.
305  ///
306  /// The Source should include the angle brackets or quotes, the dest
307  /// should not. This allows for distinction between <> and "" headers.
308  void AddIncludeAlias(StringRef Source, StringRef Dest) {
309  if (!IncludeAliases)
310  IncludeAliases.reset(new IncludeAliasMap);
311  (*IncludeAliases)[Source] = Dest;
312  }
313 
314  /// Maps one header file name to a different header
315  /// file name, for use with the include_alias pragma. Note that the source
316  /// file name should include the angle brackets or quotes. Returns StringRef
317  /// as null if the header cannot be mapped.
318  StringRef MapHeaderToIncludeAlias(StringRef Source) {
319  assert(IncludeAliases && "Trying to map headers when there's no map");
320 
321  // Do any filename replacements before anything else
322  IncludeAliasMap::const_iterator Iter = IncludeAliases->find(Source);
323  if (Iter != IncludeAliases->end())
324  return Iter->second;
325  return {};
326  }
327 
328  /// Set the path to the module cache.
329  void setModuleCachePath(StringRef CachePath) {
330  ModuleCachePath = CachePath;
331  }
332 
333  /// Retrieve the path to the module cache.
334  StringRef getModuleCachePath() const { return ModuleCachePath; }
335 
336  /// Consider modules when including files from this directory.
338  DirectoryHasModuleMap[Dir] = true;
339  }
340 
341  /// Forget everything we know about headers so far.
342  void ClearFileInfo() {
343  FileInfo.clear();
344  }
345 
347  ExternalLookup = EPS;
348  }
349 
351  return ExternalLookup;
352  }
353 
354  /// Set the external source of header information.
356  ExternalSource = ES;
357  }
358 
359  /// Set the target information for the header search, if not
360  /// already known.
361  void setTarget(const TargetInfo &Target);
362 
363  /// Given a "foo" or <foo> reference, look up the indicated file,
364  /// return null on failure.
365  ///
366  /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member
367  /// the file was found in, or null if not applicable.
368  ///
369  /// \param IncludeLoc Used for diagnostics if valid.
370  ///
371  /// \param isAngled indicates whether the file reference is a <> reference.
372  ///
373  /// \param CurDir If non-null, the file was found in the specified directory
374  /// search location. This is used to implement \#include_next.
375  ///
376  /// \param Includers Indicates where the \#including file(s) are, in case
377  /// relative searches are needed. In reverse order of inclusion.
378  ///
379  /// \param SearchPath If non-null, will be set to the search path relative
380  /// to which the file was found. If the include path is absolute, SearchPath
381  /// will be set to an empty string.
382  ///
383  /// \param RelativePath If non-null, will be set to the path relative to
384  /// SearchPath at which the file was found. This only differs from the
385  /// Filename for framework includes.
386  ///
387  /// \param SuggestedModule If non-null, and the file found is semantically
388  /// part of a known module, this will be set to the module that should
389  /// be imported instead of preprocessing/parsing the file found.
390  ///
391  /// \param IsMapped If non-null, and the search involved header maps, set to
392  /// true.
393  ///
394  /// \param IsFrameworkFound If non-null, will be set to true if a framework is
395  /// found in any of searched SearchDirs. Will be set to false if a framework
396  /// is found only through header maps. Doesn't guarantee the requested file is
397  /// found.
398  const FileEntry *LookupFile(
399  StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
400  const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir,
401  ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
402  SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
403  Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
404  bool *IsMapped, bool *IsFrameworkFound, bool SkipCache = false,
405  bool BuildSystemModule = false);
406 
407  /// Look up a subframework for the specified \#include file.
408  ///
409  /// For example, if \#include'ing <HIToolbox/HIToolbox.h> from
410  /// within ".../Carbon.framework/Headers/Carbon.h", check to see if
411  /// HIToolbox is a subframework within Carbon.framework. If so, return
412  /// the FileEntry for the designated file, otherwise return null.
413  const FileEntry *LookupSubframeworkHeader(
414  StringRef Filename, const FileEntry *ContextFileEnt,
415  SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
416  Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule);
417 
418  /// Look up the specified framework name in our framework cache.
419  /// \returns The DirectoryEntry it is in if we know, null otherwise.
421  return FrameworkMap[FWName];
422  }
423 
424  /// Mark the specified file as a target of a \#include,
425  /// \#include_next, or \#import directive.
426  ///
427  /// \return false if \#including the file will have no effect or true
428  /// if we should include it.
429  bool ShouldEnterIncludeFile(Preprocessor &PP, const FileEntry *File,
430  bool isImport, bool ModulesEnabled,
431  Module *M);
432 
433  /// Return whether the specified file is a normal header,
434  /// a system header, or a C++ friendly system header.
436  return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo;
437  }
438 
439  /// Mark the specified file as a "once only" file, e.g. due to
440  /// \#pragma once.
441  void MarkFileIncludeOnce(const FileEntry *File) {
442  HeaderFileInfo &FI = getFileInfo(File);
443  FI.isImport = true;
444  FI.isPragmaOnce = true;
445  }
446 
447  /// Mark the specified file as a system header, e.g. due to
448  /// \#pragma GCC system_header.
449  void MarkFileSystemHeader(const FileEntry *File) {
450  getFileInfo(File).DirInfo = SrcMgr::C_System;
451  }
452 
453  /// Mark the specified file as part of a module.
454  void MarkFileModuleHeader(const FileEntry *FE,
457 
458  /// Increment the count for the number of times the specified
459  /// FileEntry has been entered.
460  void IncrementIncludeCount(const FileEntry *File) {
461  ++getFileInfo(File).NumIncludes;
462  }
463 
464  /// Mark the specified file as having a controlling macro.
465  ///
466  /// This is used by the multiple-include optimization to eliminate
467  /// no-op \#includes.
470  getFileInfo(File).ControllingMacro = ControllingMacro;
471  }
472 
473  /// Return true if this is the first time encountering this header.
474  bool FirstTimeLexingFile(const FileEntry *File) {
475  return getFileInfo(File).NumIncludes == 1;
476  }
477 
478  /// Determine whether this file is intended to be safe from
479  /// multiple inclusions, e.g., it has \#pragma once or a controlling
480  /// macro.
481  ///
482  /// This routine does not consider the effect of \#import
483  bool isFileMultipleIncludeGuarded(const FileEntry *File);
484 
485  /// This method returns a HeaderMap for the specified
486  /// FileEntry, uniquing them through the 'HeaderMaps' datastructure.
487  const HeaderMap *CreateHeaderMap(const FileEntry *FE);
488 
489  /// Get filenames for all registered header maps.
490  void getHeaderMapFileNames(SmallVectorImpl<std::string> &Names) const;
491 
492  /// Retrieve the name of the cached module file that should be used
493  /// to load the given module.
494  ///
495  /// \param Module The module whose module file name will be returned.
496  ///
497  /// \returns The name of the module file that corresponds to this module,
498  /// or an empty string if this module does not correspond to any module file.
499  std::string getCachedModuleFileName(Module *Module);
500 
501  /// Retrieve the name of the prebuilt module file that should be used
502  /// to load a module with the given name.
503  ///
504  /// \param ModuleName The module whose module file name will be returned.
505  ///
506  /// \param FileMapOnly If true, then only look in the explicit module name
507  // to file name map and skip the directory search.
508  ///
509  /// \returns The name of the module file that corresponds to this module,
510  /// or an empty string if this module does not correspond to any module file.
511  std::string getPrebuiltModuleFileName(StringRef ModuleName,
512  bool FileMapOnly = false);
513 
514  /// Retrieve the name of the (to-be-)cached module file that should
515  /// be used to load a module with the given name.
516  ///
517  /// \param ModuleName The module whose module file name will be returned.
518  ///
519  /// \param ModuleMapPath A path that when combined with \c ModuleName
520  /// uniquely identifies this module. See Module::ModuleMap.
521  ///
522  /// \returns The name of the module file that corresponds to this module,
523  /// or an empty string if this module does not correspond to any module file.
524  std::string getCachedModuleFileName(StringRef ModuleName,
525  StringRef ModuleMapPath);
526 
527  /// Lookup a module Search for a module with the given name.
528  ///
529  /// \param ModuleName The name of the module we're looking for.
530  ///
531  /// \param AllowSearch Whether we are allowed to search in the various
532  /// search directories to produce a module definition. If not, this lookup
533  /// will only return an already-known module.
534  ///
535  /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
536  /// in subdirectories.
537  ///
538  /// \returns The module with the given name.
539  Module *lookupModule(StringRef ModuleName, bool AllowSearch = true,
540  bool AllowExtraModuleMapSearch = false);
541 
542  /// Try to find a module map file in the given directory, returning
543  /// \c nullptr if none is found.
544  const FileEntry *lookupModuleMapFile(const DirectoryEntry *Dir,
545  bool IsFramework);
546 
547  void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; }
548 
549  /// Determine whether there is a module map that may map the header
550  /// with the given file name to a (sub)module.
551  /// Always returns false if modules are disabled.
552  ///
553  /// \param Filename The name of the file.
554  ///
555  /// \param Root The "root" directory, at which we should stop looking for
556  /// module maps.
557  ///
558  /// \param IsSystem Whether the directories we're looking at are system
559  /// header directories.
560  bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root,
561  bool IsSystem);
562 
563  /// Retrieve the module that corresponds to the given file, if any.
564  ///
565  /// \param File The header that we wish to map to a module.
566  /// \param AllowTextual Whether we want to find textual headers too.
567  ModuleMap::KnownHeader findModuleForHeader(const FileEntry *File,
568  bool AllowTextual = false) const;
569 
570  /// Read the contents of the given module map file.
571  ///
572  /// \param File The module map file.
573  /// \param IsSystem Whether this file is in a system header directory.
574  /// \param ID If the module map file is already mapped (perhaps as part of
575  /// processing a preprocessed module), the ID of the file.
576  /// \param Offset [inout] An offset within ID to start parsing. On exit,
577  /// filled by the end of the parsed contents (either EOF or the
578  /// location of an end-of-module-map pragma).
579  /// \param OriginalModuleMapFile The original path to the module map file,
580  /// used to resolve paths within the module (this is required when
581  /// building the module from preprocessed source).
582  /// \returns true if an error occurred, false otherwise.
583  bool loadModuleMapFile(const FileEntry *File, bool IsSystem,
584  FileID ID = FileID(), unsigned *Offset = nullptr,
585  StringRef OriginalModuleMapFile = StringRef());
586 
587  /// Collect the set of all known, top-level modules.
588  ///
589  /// \param Modules Will be filled with the set of known, top-level modules.
590  void collectAllModules(SmallVectorImpl<Module *> &Modules);
591 
592  /// Load all known, top-level system modules.
593  void loadTopLevelSystemModules();
594 
595 private:
596  /// Lookup a module with the given module name and search-name.
597  ///
598  /// \param ModuleName The name of the module we're looking for.
599  ///
600  /// \param SearchName The "search-name" to derive filesystem paths from
601  /// when looking for the module map; this is usually equal to ModuleName,
602  /// but for compatibility with some buggy frameworks, additional attempts
603  /// may be made to find the module under a related-but-different search-name.
604  ///
605  /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
606  /// in subdirectories.
607  ///
608  /// \returns The module named ModuleName.
609  Module *lookupModule(StringRef ModuleName, StringRef SearchName,
610  bool AllowExtraModuleMapSearch = false);
611 
612  /// Retrieve a module with the given name, which may be part of the
613  /// given framework.
614  ///
615  /// \param Name The name of the module to retrieve.
616  ///
617  /// \param Dir The framework directory (e.g., ModuleName.framework).
618  ///
619  /// \param IsSystem Whether the framework directory is part of the system
620  /// frameworks.
621  ///
622  /// \returns The module, if found; otherwise, null.
623  Module *loadFrameworkModule(StringRef Name,
624  const DirectoryEntry *Dir,
625  bool IsSystem);
626 
627  /// Load all of the module maps within the immediate subdirectories
628  /// of the given search directory.
629  void loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir);
630 
631  /// Find and suggest a usable module for the given file.
632  ///
633  /// \return \c true if the file can be used, \c false if we are not permitted to
634  /// find this file due to requirements from \p RequestingModule.
635  bool findUsableModuleForHeader(const FileEntry *File,
636  const DirectoryEntry *Root,
637  Module *RequestingModule,
638  ModuleMap::KnownHeader *SuggestedModule,
639  bool IsSystemHeaderDir);
640 
641  /// Find and suggest a usable module for the given file, which is part of
642  /// the specified framework.
643  ///
644  /// \return \c true if the file can be used, \c false if we are not permitted to
645  /// find this file due to requirements from \p RequestingModule.
646  bool findUsableModuleForFrameworkHeader(
647  const FileEntry *File, StringRef FrameworkName, Module *RequestingModule,
648  ModuleMap::KnownHeader *SuggestedModule, bool IsSystemFramework);
649 
650  /// Look up the file with the specified name and determine its owning
651  /// module.
652  const FileEntry *
653  getFileAndSuggestModule(StringRef FileName, SourceLocation IncludeLoc,
654  const DirectoryEntry *Dir, bool IsSystemHeaderDir,
655  Module *RequestingModule,
656  ModuleMap::KnownHeader *SuggestedModule);
657 
658 public:
659  /// Retrieve the module map.
660  ModuleMap &getModuleMap() { return ModMap; }
661 
662  /// Retrieve the module map.
663  const ModuleMap &getModuleMap() const { return ModMap; }
664 
665  unsigned header_file_size() const { return FileInfo.size(); }
666 
667  /// Return the HeaderFileInfo structure for the specified FileEntry,
668  /// in preparation for updating it in some way.
669  HeaderFileInfo &getFileInfo(const FileEntry *FE);
670 
671  /// Return the HeaderFileInfo structure for the specified FileEntry,
672  /// if it has ever been filled in.
673  /// \param WantExternal Whether the caller wants purely-external header file
674  /// info (where \p External is true).
675  const HeaderFileInfo *getExistingFileInfo(const FileEntry *FE,
676  bool WantExternal = true) const;
677 
678  // Used by external tools
679  using search_dir_iterator = std::vector<DirectoryLookup>::const_iterator;
680 
681  search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); }
682  search_dir_iterator search_dir_end() const { return SearchDirs.end(); }
683  unsigned search_dir_size() const { return SearchDirs.size(); }
684 
686  return SearchDirs.begin();
687  }
688 
690  return SearchDirs.begin() + AngledDirIdx;
691  }
692 
694  return SearchDirs.begin() + AngledDirIdx;
695  }
696 
698  return SearchDirs.begin() + SystemDirIdx;
699  }
700 
702  return SearchDirs.begin() + SystemDirIdx;
703  }
704 
705  search_dir_iterator system_dir_end() const { return SearchDirs.end(); }
706 
707  /// Retrieve a uniqued framework name.
708  StringRef getUniqueFrameworkName(StringRef Framework);
709 
710  /// Suggest a path by which the specified file could be found, for use in
711  /// diagnostics to suggest a #include. Returned path will only contain forward
712  /// slashes as separators. MainFile is the absolute path of the file that we
713  /// are generating the diagnostics for. It will try to shorten the path using
714  /// MainFile location, if none of the include search directories were prefix
715  /// of File.
716  ///
717  /// \param IsSystem If non-null, filled in to indicate whether the suggested
718  /// path is relative to a system header directory.
719  std::string suggestPathToFileForDiagnostics(const FileEntry *File,
720  llvm::StringRef MainFile,
721  bool *IsSystem = nullptr);
722 
723  /// Suggest a path by which the specified file could be found, for use in
724  /// diagnostics to suggest a #include. Returned path will only contain forward
725  /// slashes as separators. MainFile is the absolute path of the file that we
726  /// are generating the diagnostics for. It will try to shorten the path using
727  /// MainFile location, if none of the include search directories were prefix
728  /// of File.
729  ///
730  /// \param WorkingDir If non-empty, this will be prepended to search directory
731  /// paths that are relative.
732  std::string suggestPathToFileForDiagnostics(llvm::StringRef File,
733  llvm::StringRef WorkingDir,
734  llvm::StringRef MainFile,
735  bool *IsSystem = nullptr);
736 
737  void PrintStats();
738 
739  size_t getTotalMemory() const;
740 
741 private:
742  /// Describes what happened when we tried to load a module map file.
743  enum LoadModuleMapResult {
744  /// The module map file had already been loaded.
745  LMM_AlreadyLoaded,
746 
747  /// The module map file was loaded by this invocation.
748  LMM_NewlyLoaded,
749 
750  /// There is was directory with the given name.
751  LMM_NoDirectory,
752 
753  /// There was either no module map file or the module map file was
754  /// invalid.
755  LMM_InvalidModuleMap
756  };
757 
758  LoadModuleMapResult loadModuleMapFileImpl(const FileEntry *File,
759  bool IsSystem,
760  const DirectoryEntry *Dir,
761  FileID ID = FileID(),
762  unsigned *Offset = nullptr);
763 
764  /// Try to load the module map file in the given directory.
765  ///
766  /// \param DirName The name of the directory where we will look for a module
767  /// map file.
768  /// \param IsSystem Whether this is a system header directory.
769  /// \param IsFramework Whether this is a framework directory.
770  ///
771  /// \returns The result of attempting to load the module map file from the
772  /// named directory.
773  LoadModuleMapResult loadModuleMapFile(StringRef DirName, bool IsSystem,
774  bool IsFramework);
775 
776  /// Try to load the module map file in the given directory.
777  ///
778  /// \param Dir The directory where we will look for a module map file.
779  /// \param IsSystem Whether this is a system header directory.
780  /// \param IsFramework Whether this is a framework directory.
781  ///
782  /// \returns The result of attempting to load the module map file from the
783  /// named directory.
784  LoadModuleMapResult loadModuleMapFile(const DirectoryEntry *Dir,
785  bool IsSystem, bool IsFramework);
786 };
787 
788 } // namespace clang
789 
790 #endif // LLVM_CLANG_LEX_HEADERSEARCH_H
unsigned DirInfo
Keep track of whether this is a system header, and if so, whether it is C++ clean or not...
Definition: HeaderSearch.h:61
Implements support for file system lookup, file system caching, and directory search management...
Definition: FileManager.h:116
unsigned isPragmaOnce
True if this is a #pragma once file.
Definition: HeaderSearch.h:55
Defines the SourceManager interface.
void SetSearchPaths(const std::vector< DirectoryLookup > &dirs, unsigned angledDirIdx, unsigned systemDirIdx, bool noCurDirSearch)
Interface for setting the file search paths.
Definition: HeaderSearch.h:275
StringRef P
search_dir_iterator angled_dir_end() const
Definition: HeaderSearch.h:697
FrameworkCacheEntry & LookupFrameworkCache(StringRef FWName)
Look up the specified framework name in our framework cache.
Definition: HeaderSearch.h:420
bool HasIncludeAliasMap() const
Checks whether the map exists or not.
Definition: HeaderSearch.h:302
CharacteristicKind
Indicates whether a file or directory holds normal user code, system code, or system code which is im...
Definition: SourceManager.h:77
ModuleMap & getModuleMap()
Retrieve the module map.
Definition: HeaderSearch.h:660
unsigned isCompilingModuleHeader
Whether this header is part of the module that we are building.
Definition: HeaderSearch.h:71
unsigned isImport
True if this is a #import&#39;d or #pragma once file.
Definition: HeaderSearch.h:52
void ClearFileInfo()
Forget everything we know about headers so far.
Definition: HeaderSearch.h:342
DiagnosticsEngine & getDiags() const
Definition: HeaderSearch.h:272
One of these records is kept for each identifier that is lexed.
This class represents an Apple concept known as a &#39;header map&#39;.
Definition: HeaderMap.h:66
FileManager & getFileMgr() const
Definition: HeaderSearch.h:270
const IdentifierInfo * getControllingMacro(ExternalPreprocessorSource *External)
Retrieve the controlling macro for this header file, if any.
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:49
Describes a module or submodule.
Definition: Module.h:64
unsigned External
Whether this header file info was supplied by an external source, and has not changed since...
Definition: HeaderSearch.h:65
void AddIncludeAlias(StringRef Source, StringRef Dest)
Map the source include name to the dest include name.
Definition: HeaderSearch.h:308
bool IsUserSpecifiedSystemFramework
Whether this framework has been "user-specified" to be treated as if it were a system framework (even...
Definition: HeaderSearch.h:153
search_dir_iterator search_dir_begin() const
Definition: HeaderSearch.h:681
search_dir_iterator quoted_dir_end() const
Definition: HeaderSearch.h:689
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:149
unsigned short NumIncludes
The number of times the file has been included already.
Definition: HeaderSearch.h:90
search_dir_iterator search_dir_end() const
Definition: HeaderSearch.h:682
unsigned Resolved
Whether this structure is considered to already have been "resolved", meaning that it was loaded from...
Definition: HeaderSearch.h:75
The preprocessor keeps track of this information for each file that is #included. ...
Definition: HeaderSearch.h:50
unsigned header_file_size() const
Definition: HeaderSearch.h:665
Encapsulates the information needed to find the file referenced by a #include or #include_next, (sub-)framework lookup, etc.
Definition: HeaderSearch.h:158
StringRef getModuleCachePath() const
Retrieve the path to the module cache.
Definition: HeaderSearch.h:334
const ModuleMap & getModuleMap() const
Retrieve the module map.
Definition: HeaderSearch.h:663
ModuleHeaderRole
Flags describing the role of a module header.
Definition: ModuleMap.h:123
StringRef Filename
Definition: Format.cpp:1711
unsigned Offset
Definition: Format.cpp:1713
Exposes information about the current target.
Definition: TargetInfo.h:161
Abstract interface for external sources of preprocessor information.
HeaderSearchOptions & getHeaderSearchOpts() const
Retrieve the header-search options with which this header search was initialized. ...
Definition: HeaderSearch.h:268
search_dir_iterator quoted_dir_begin() const
Definition: HeaderSearch.h:685
search_dir_iterator system_dir_end() const
Definition: HeaderSearch.h:705
void IncrementIncludeCount(const FileEntry *File)
Increment the count for the number of times the specified FileEntry has been entered.
Definition: HeaderSearch.h:460
DirectoryLookup - This class represents one entry in the search list that specifies the search order ...
const DirectoryEntry * Directory
The directory entry which should be used for the cached framework.
Definition: HeaderSearch.h:148
SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File)
Return whether the specified file is a normal header, a system header, or a C++ friendly system heade...
Definition: HeaderSearch.h:435
unsigned isModuleHeader
Whether this header is part of a module.
Definition: HeaderSearch.h:68
#define false
Definition: stdbool.h:17
Encodes a location in the source.
search_dir_iterator system_dir_begin() const
Definition: HeaderSearch.h:701
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:59
const IdentifierInfo * ControllingMacro
If this file has a #ifndef XXX (or equivalent) guard that protects the entire contents of the file...
Definition: HeaderSearch.h:107
An opaque identifier used by SourceManager which refers to a source file (MemoryBuffer) along with it...
unsigned ControllingMacroID
The ID number of the controlling macro.
Definition: HeaderSearch.h:97
Dataflow Directional Tag Classes.
An external source of header file information, which may supply information about header files alread...
Definition: HeaderSearch.h:133
bool isNonDefault() const
Determine whether this is a non-default header file info, e.g., it corresponds to an actual header we...
Definition: HeaderSearch.h:125
void SetExternalSource(ExternalHeaderFileInfoSource *ES)
Set the external source of header information.
Definition: HeaderSearch.h:355
void IncrementFrameworkLookupCount()
Definition: HeaderSearch.h:547
std::vector< DirectoryLookup >::const_iterator search_dir_iterator
Definition: HeaderSearch.h:679
void AddSearchPath(const DirectoryLookup &dir, bool isAngled)
Add an additional search path.
Definition: HeaderSearch.h:288
search_dir_iterator angled_dir_begin() const
Definition: HeaderSearch.h:693
Cached information about one directory (either on disk or in the virtual file system).
Definition: FileManager.h:45
StringRef Framework
If this header came from a framework include, this is the name of the framework.
Definition: HeaderSearch.h:111
Defines the clang::SourceLocation class and associated facilities.
void setDirectoryHasModuleMap(const DirectoryEntry *Dir)
Consider modules when including files from this directory.
Definition: HeaderSearch.h:337
void SetSystemHeaderPrefixes(ArrayRef< std::pair< std::string, bool >> P)
Set the list of system header prefixes.
Definition: HeaderSearch.h:297
HeaderSearchOptions - Helper class for storing options related to the initialization of the HeaderSea...
StringRef MapHeaderToIncludeAlias(StringRef Source)
Maps one header file name to a different header file name, for use with the include_alias pragma...
Definition: HeaderSearch.h:318
bool FirstTimeLexingFile(const FileEntry *File)
Return true if this is the first time encountering this header.
Definition: HeaderSearch.h:474
void SetExternalLookup(ExternalPreprocessorSource *EPS)
Definition: HeaderSearch.h:346
unsigned IndexHeaderMapHeader
Whether this is a header inside a framework that is currently being built.
Definition: HeaderSearch.h:84
unsigned IsValid
Whether this file has been looked up as a header.
Definition: HeaderSearch.h:87
void MarkFileSystemHeader(const FileEntry *File)
Mark the specified file as a system header, e.g.
Definition: HeaderSearch.h:449
This structure is used to record entries in our framework cache.
Definition: HeaderSearch.h:146
unsigned search_dir_size() const
Definition: HeaderSearch.h:683
A header that is known to reside within a given module, whether it was included or excluded...
Definition: ModuleMap.h:150
void MarkFileIncludeOnce(const FileEntry *File)
Mark the specified file as a "once only" file, e.g.
Definition: HeaderSearch.h:441
void setModuleCachePath(StringRef CachePath)
Set the path to the module cache.
Definition: HeaderSearch.h:329
This class handles loading and caching of source files into memory.
ExternalPreprocessorSource * getExternalLookup() const
Definition: HeaderSearch.h:350
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:124
void SetFileControllingMacro(const FileEntry *File, const IdentifierInfo *ControllingMacro)
Mark the specified file as having a controlling macro.
Definition: HeaderSearch.h:468