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. Doesn't guarantee the requested file
396  /// is found.
397  const FileEntry *LookupFile(
398  StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
399  const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir,
400  ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
401  SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
402  Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
403  bool *IsMapped, bool *IsFrameworkFound, bool SkipCache = false,
404  bool BuildSystemModule = false);
405 
406  /// Look up a subframework for the specified \#include file.
407  ///
408  /// For example, if \#include'ing <HIToolbox/HIToolbox.h> from
409  /// within ".../Carbon.framework/Headers/Carbon.h", check to see if
410  /// HIToolbox is a subframework within Carbon.framework. If so, return
411  /// the FileEntry for the designated file, otherwise return null.
412  const FileEntry *LookupSubframeworkHeader(
413  StringRef Filename, const FileEntry *ContextFileEnt,
414  SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
415  Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule);
416 
417  /// Look up the specified framework name in our framework cache.
418  /// \returns The DirectoryEntry it is in if we know, null otherwise.
420  return FrameworkMap[FWName];
421  }
422 
423  /// Mark the specified file as a target of a \#include,
424  /// \#include_next, or \#import directive.
425  ///
426  /// \return false if \#including the file will have no effect or true
427  /// if we should include it.
428  bool ShouldEnterIncludeFile(Preprocessor &PP, const FileEntry *File,
429  bool isImport, bool ModulesEnabled,
430  Module *M);
431 
432  /// Return whether the specified file is a normal header,
433  /// a system header, or a C++ friendly system header.
435  return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo;
436  }
437 
438  /// Mark the specified file as a "once only" file, e.g. due to
439  /// \#pragma once.
440  void MarkFileIncludeOnce(const FileEntry *File) {
441  HeaderFileInfo &FI = getFileInfo(File);
442  FI.isImport = true;
443  FI.isPragmaOnce = true;
444  }
445 
446  /// Mark the specified file as a system header, e.g. due to
447  /// \#pragma GCC system_header.
448  void MarkFileSystemHeader(const FileEntry *File) {
449  getFileInfo(File).DirInfo = SrcMgr::C_System;
450  }
451 
452  /// Mark the specified file as part of a module.
453  void MarkFileModuleHeader(const FileEntry *FE,
456 
457  /// Increment the count for the number of times the specified
458  /// FileEntry has been entered.
459  void IncrementIncludeCount(const FileEntry *File) {
460  ++getFileInfo(File).NumIncludes;
461  }
462 
463  /// Mark the specified file as having a controlling macro.
464  ///
465  /// This is used by the multiple-include optimization to eliminate
466  /// no-op \#includes.
469  getFileInfo(File).ControllingMacro = ControllingMacro;
470  }
471 
472  /// Return true if this is the first time encountering this header.
473  bool FirstTimeLexingFile(const FileEntry *File) {
474  return getFileInfo(File).NumIncludes == 1;
475  }
476 
477  /// Determine whether this file is intended to be safe from
478  /// multiple inclusions, e.g., it has \#pragma once or a controlling
479  /// macro.
480  ///
481  /// This routine does not consider the effect of \#import
482  bool isFileMultipleIncludeGuarded(const FileEntry *File);
483 
484  /// This method returns a HeaderMap for the specified
485  /// FileEntry, uniquing them through the 'HeaderMaps' datastructure.
486  const HeaderMap *CreateHeaderMap(const FileEntry *FE);
487 
488  /// Get filenames for all registered header maps.
489  void getHeaderMapFileNames(SmallVectorImpl<std::string> &Names) const;
490 
491  /// Retrieve the name of the cached module file that should be used
492  /// to load the given module.
493  ///
494  /// \param Module The module whose module file name will be returned.
495  ///
496  /// \returns The name of the module file that corresponds to this module,
497  /// or an empty string if this module does not correspond to any module file.
498  std::string getCachedModuleFileName(Module *Module);
499 
500  /// Retrieve the name of the prebuilt module file that should be used
501  /// to load a module with the given name.
502  ///
503  /// \param ModuleName The module whose module file name will be returned.
504  ///
505  /// \param FileMapOnly If true, then only look in the explicit module name
506  // to file name map and skip the directory search.
507  ///
508  /// \returns The name of the module file that corresponds to this module,
509  /// or an empty string if this module does not correspond to any module file.
510  std::string getPrebuiltModuleFileName(StringRef ModuleName,
511  bool FileMapOnly = false);
512 
513  /// Retrieve the name of the (to-be-)cached module file that should
514  /// be used to load a module with the given name.
515  ///
516  /// \param ModuleName The module whose module file name will be returned.
517  ///
518  /// \param ModuleMapPath A path that when combined with \c ModuleName
519  /// uniquely identifies this module. See Module::ModuleMap.
520  ///
521  /// \returns The name of the module file that corresponds to this module,
522  /// or an empty string if this module does not correspond to any module file.
523  std::string getCachedModuleFileName(StringRef ModuleName,
524  StringRef ModuleMapPath);
525 
526  /// Lookup a module Search for a module with the given name.
527  ///
528  /// \param ModuleName The name of the module we're looking for.
529  ///
530  /// \param AllowSearch Whether we are allowed to search in the various
531  /// search directories to produce a module definition. If not, this lookup
532  /// will only return an already-known module.
533  ///
534  /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
535  /// in subdirectories.
536  ///
537  /// \returns The module with the given name.
538  Module *lookupModule(StringRef ModuleName, bool AllowSearch = true,
539  bool AllowExtraModuleMapSearch = false);
540 
541  /// Try to find a module map file in the given directory, returning
542  /// \c nullptr if none is found.
543  const FileEntry *lookupModuleMapFile(const DirectoryEntry *Dir,
544  bool IsFramework);
545 
546  void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; }
547 
548  /// Determine whether there is a module map that may map the header
549  /// with the given file name to a (sub)module.
550  /// Always returns false if modules are disabled.
551  ///
552  /// \param Filename The name of the file.
553  ///
554  /// \param Root The "root" directory, at which we should stop looking for
555  /// module maps.
556  ///
557  /// \param IsSystem Whether the directories we're looking at are system
558  /// header directories.
559  bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root,
560  bool IsSystem);
561 
562  /// Retrieve the module that corresponds to the given file, if any.
563  ///
564  /// \param File The header that we wish to map to a module.
565  /// \param AllowTextual Whether we want to find textual headers too.
566  ModuleMap::KnownHeader findModuleForHeader(const FileEntry *File,
567  bool AllowTextual = false) const;
568 
569  /// Read the contents of the given module map file.
570  ///
571  /// \param File The module map file.
572  /// \param IsSystem Whether this file is in a system header directory.
573  /// \param ID If the module map file is already mapped (perhaps as part of
574  /// processing a preprocessed module), the ID of the file.
575  /// \param Offset [inout] An offset within ID to start parsing. On exit,
576  /// filled by the end of the parsed contents (either EOF or the
577  /// location of an end-of-module-map pragma).
578  /// \param OriginalModuleMapFile The original path to the module map file,
579  /// used to resolve paths within the module (this is required when
580  /// building the module from preprocessed source).
581  /// \returns true if an error occurred, false otherwise.
582  bool loadModuleMapFile(const FileEntry *File, bool IsSystem,
583  FileID ID = FileID(), unsigned *Offset = nullptr,
584  StringRef OriginalModuleMapFile = StringRef());
585 
586  /// Collect the set of all known, top-level modules.
587  ///
588  /// \param Modules Will be filled with the set of known, top-level modules.
589  void collectAllModules(SmallVectorImpl<Module *> &Modules);
590 
591  /// Load all known, top-level system modules.
592  void loadTopLevelSystemModules();
593 
594 private:
595  /// Lookup a module with the given module name and search-name.
596  ///
597  /// \param ModuleName The name of the module we're looking for.
598  ///
599  /// \param SearchName The "search-name" to derive filesystem paths from
600  /// when looking for the module map; this is usually equal to ModuleName,
601  /// but for compatibility with some buggy frameworks, additional attempts
602  /// may be made to find the module under a related-but-different search-name.
603  ///
604  /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
605  /// in subdirectories.
606  ///
607  /// \returns The module named ModuleName.
608  Module *lookupModule(StringRef ModuleName, StringRef SearchName,
609  bool AllowExtraModuleMapSearch = false);
610 
611  /// Retrieve a module with the given name, which may be part of the
612  /// given framework.
613  ///
614  /// \param Name The name of the module to retrieve.
615  ///
616  /// \param Dir The framework directory (e.g., ModuleName.framework).
617  ///
618  /// \param IsSystem Whether the framework directory is part of the system
619  /// frameworks.
620  ///
621  /// \returns The module, if found; otherwise, null.
622  Module *loadFrameworkModule(StringRef Name,
623  const DirectoryEntry *Dir,
624  bool IsSystem);
625 
626  /// Load all of the module maps within the immediate subdirectories
627  /// of the given search directory.
628  void loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir);
629 
630  /// Find and suggest a usable module for the given file.
631  ///
632  /// \return \c true if the file can be used, \c false if we are not permitted to
633  /// find this file due to requirements from \p RequestingModule.
634  bool findUsableModuleForHeader(const FileEntry *File,
635  const DirectoryEntry *Root,
636  Module *RequestingModule,
637  ModuleMap::KnownHeader *SuggestedModule,
638  bool IsSystemHeaderDir);
639 
640  /// Find and suggest a usable module for the given file, which is part of
641  /// the specified framework.
642  ///
643  /// \return \c true if the file can be used, \c false if we are not permitted to
644  /// find this file due to requirements from \p RequestingModule.
645  bool findUsableModuleForFrameworkHeader(
646  const FileEntry *File, StringRef FrameworkName, Module *RequestingModule,
647  ModuleMap::KnownHeader *SuggestedModule, bool IsSystemFramework);
648 
649  /// Look up the file with the specified name and determine its owning
650  /// module.
651  const FileEntry *
652  getFileAndSuggestModule(StringRef FileName, SourceLocation IncludeLoc,
653  const DirectoryEntry *Dir, bool IsSystemHeaderDir,
654  Module *RequestingModule,
655  ModuleMap::KnownHeader *SuggestedModule);
656 
657 public:
658  /// Retrieve the module map.
659  ModuleMap &getModuleMap() { return ModMap; }
660 
661  /// Retrieve the module map.
662  const ModuleMap &getModuleMap() const { return ModMap; }
663 
664  unsigned header_file_size() const { return FileInfo.size(); }
665 
666  /// Return the HeaderFileInfo structure for the specified FileEntry,
667  /// in preparation for updating it in some way.
668  HeaderFileInfo &getFileInfo(const FileEntry *FE);
669 
670  /// Return the HeaderFileInfo structure for the specified FileEntry,
671  /// if it has ever been filled in.
672  /// \param WantExternal Whether the caller wants purely-external header file
673  /// info (where \p External is true).
674  const HeaderFileInfo *getExistingFileInfo(const FileEntry *FE,
675  bool WantExternal = true) const;
676 
677  // Used by external tools
678  using search_dir_iterator = std::vector<DirectoryLookup>::const_iterator;
679 
680  search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); }
681  search_dir_iterator search_dir_end() const { return SearchDirs.end(); }
682  unsigned search_dir_size() const { return SearchDirs.size(); }
683 
685  return SearchDirs.begin();
686  }
687 
689  return SearchDirs.begin() + AngledDirIdx;
690  }
691 
693  return SearchDirs.begin() + AngledDirIdx;
694  }
695 
697  return SearchDirs.begin() + SystemDirIdx;
698  }
699 
701  return SearchDirs.begin() + SystemDirIdx;
702  }
703 
704  search_dir_iterator system_dir_end() const { return SearchDirs.end(); }
705 
706  /// Retrieve a uniqued framework name.
707  StringRef getUniqueFrameworkName(StringRef Framework);
708 
709  /// Suggest a path by which the specified file could be found, for
710  /// use in diagnostics to suggest a #include.
711  ///
712  /// \param IsSystem If non-null, filled in to indicate whether the suggested
713  /// path is relative to a system header directory.
714  std::string suggestPathToFileForDiagnostics(const FileEntry *File,
715  bool *IsSystem = nullptr);
716 
717  /// Suggest a path by which the specified file could be found, for
718  /// use in diagnostics to suggest a #include.
719  ///
720  /// \param WorkingDir If non-empty, this will be prepended to search directory
721  /// paths that are relative.
722  std::string suggestPathToFileForDiagnostics(llvm::StringRef File,
723  llvm::StringRef WorkingDir,
724  bool *IsSystem = nullptr);
725 
726  void PrintStats();
727 
728  size_t getTotalMemory() const;
729 
730 private:
731  /// Describes what happened when we tried to load a module map file.
732  enum LoadModuleMapResult {
733  /// The module map file had already been loaded.
734  LMM_AlreadyLoaded,
735 
736  /// The module map file was loaded by this invocation.
737  LMM_NewlyLoaded,
738 
739  /// There is was directory with the given name.
740  LMM_NoDirectory,
741 
742  /// There was either no module map file or the module map file was
743  /// invalid.
744  LMM_InvalidModuleMap
745  };
746 
747  LoadModuleMapResult loadModuleMapFileImpl(const FileEntry *File,
748  bool IsSystem,
749  const DirectoryEntry *Dir,
750  FileID ID = FileID(),
751  unsigned *Offset = nullptr);
752 
753  /// Try to load the module map file in the given directory.
754  ///
755  /// \param DirName The name of the directory where we will look for a module
756  /// map file.
757  /// \param IsSystem Whether this is a system header directory.
758  /// \param IsFramework Whether this is a framework directory.
759  ///
760  /// \returns The result of attempting to load the module map file from the
761  /// named directory.
762  LoadModuleMapResult loadModuleMapFile(StringRef DirName, bool IsSystem,
763  bool IsFramework);
764 
765  /// Try to load the module map file in the given directory.
766  ///
767  /// \param Dir The directory where we will look for a module 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(const DirectoryEntry *Dir,
774  bool IsSystem, bool IsFramework);
775 };
776 
777 } // namespace clang
778 
779 #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:120
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:696
FrameworkCacheEntry & LookupFrameworkCache(StringRef FWName)
Look up the specified framework name in our framework cache.
Definition: HeaderSearch.h:419
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:659
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:680
search_dir_iterator quoted_dir_end() const
Definition: HeaderSearch.h:688
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:148
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:681
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:664
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:662
ModuleHeaderRole
Flags describing the role of a module header.
Definition: ModuleMap.h:123
StringRef Filename
Definition: Format.cpp:1628
unsigned Offset
Definition: Format.cpp:1630
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:684
search_dir_iterator system_dir_end() const
Definition: HeaderSearch.h:704
void IncrementIncludeCount(const FileEntry *File)
Increment the count for the number of times the specified FileEntry has been entered.
Definition: HeaderSearch.h:459
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:434
unsigned isModuleHeader
Whether this header is part of a module.
Definition: HeaderSearch.h:68
#define false
Definition: stdbool.h:33
Encodes a location in the source.
search_dir_iterator system_dir_begin() const
Definition: HeaderSearch.h:700
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:546
std::vector< DirectoryLookup >::const_iterator search_dir_iterator
Definition: HeaderSearch.h:678
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:692
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:473
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:448
This structure is used to record entries in our framework cache.
Definition: HeaderSearch.h:146
unsigned search_dir_size() const
Definition: HeaderSearch.h:682
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:440
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:467