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
16#include "clang/Basic/SourceLocation.h"
17#include "clang/Basic/SourceManager.h"
18#include "clang/Lex/DirectoryLookup.h"
19#include "clang/Lex/ExternalPreprocessorSource.h"
20#include "clang/Lex/HeaderMap.h"
21#include "clang/Lex/ModuleMap.h"
22#include "llvm/ADT/ArrayRef.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/ADT/MapVector.h"
25#include "llvm/ADT/SmallString.h"
26#include "llvm/ADT/StringMap.h"
27#include "llvm/ADT/StringRef.h"
28#include "llvm/ADT/StringSet.h"
29#include "llvm/Support/Allocator.h"
30#include <cassert>
31#include <cstddef>
32#include <memory>
33#include <string>
34#include <utility>
35#include <vector>
36
37namespace llvm {
38
39class Triple;
40
41} // namespace llvm
42
43namespace clang {
44
45class DiagnosticsEngine;
46class DirectoryEntry;
47class ExternalPreprocessorSource;
48class FileEntry;
49class FileManager;
50class HeaderSearch;
51class HeaderSearchOptions;
52class IdentifierInfo;
53class LangOptions;
54class Module;
55class Preprocessor;
56class TargetInfo;
57
58/// The preprocessor keeps track of this information for each
59/// file that is \#included.
60struct HeaderFileInfo {
61 // TODO: Whether the file was included is not a property of the file itself.
62 // It's a preprocessor state, move it there.
63 /// True if this file has been included (or imported) **locally**.
64 LLVM_PREFERRED_TYPE(bool)
65 unsigned IsLocallyIncluded : 1;
66
67 // TODO: Whether the file was imported is not a property of the file itself.
68 // It's a preprocessor state, move it there.
69 /// True if this is a \#import'd file.
70 LLVM_PREFERRED_TYPE(bool)
71 unsigned isImport : 1;
72
73 /// True if this is a \#pragma once file.
74 LLVM_PREFERRED_TYPE(bool)
75 unsigned isPragmaOnce : 1;
76
77 /// Keep track of whether this is a system header, and if so,
78 /// whether it is C++ clean or not. This can be set by the include paths or
79 /// by \#pragma gcc system_header. This is an instance of
80 /// SrcMgr::CharacteristicKind.
81 LLVM_PREFERRED_TYPE(SrcMgr::CharacteristicKind)
82 unsigned DirInfo : 3;
83
84 /// Whether this header file info was supplied by an external source,
85 /// and has not changed since.
86 LLVM_PREFERRED_TYPE(bool)
87 unsigned External : 1;
88
89 /// Whether this header is part of and built with a module. i.e. it is listed
90 /// in a module map, and is not `excluded` or `textual`. (same meaning as
91 /// `ModuleMap::isModular()`).
92 LLVM_PREFERRED_TYPE(bool)
93 unsigned isModuleHeader : 1;
94
95 /// Whether this header is a `textual header` in a module. If a header is
96 /// textual in one module and normal in another module, this bit will not be
97 /// set, only `isModuleHeader`.
98 LLVM_PREFERRED_TYPE(bool)
99 unsigned isTextualModuleHeader : 1;
100
101 /// Whether this header is part of the module that we are building, even if it
102 /// doesn't build with the module. i.e. this will include `excluded` and
103 /// `textual` headers as well as normal headers.
104 LLVM_PREFERRED_TYPE(bool)
105 unsigned isCompilingModuleHeader : 1;
106
107 /// Whether this structure is considered to already have been
108 /// "resolved", meaning that it was loaded from the external source.
109 LLVM_PREFERRED_TYPE(bool)
110 unsigned Resolved : 1;
111
112 /// Whether this file has been looked up as a header.
113 LLVM_PREFERRED_TYPE(bool)
114 unsigned IsValid : 1;
115
116 /// If this file has a \#ifndef XXX (or equivalent) guard that
117 /// protects the entire contents of the file, this is the identifier
118 /// for the macro that controls whether or not it has any effect.
119 ///
120 /// Note: Most clients should use getControllingMacro() to access
121 /// the controlling macro of this header, since
122 /// getControllingMacro() is able to load a controlling macro from
123 /// external storage.
124 LazyIdentifierInfoPtr LazyControllingMacro;
125
126 HeaderFileInfo()
127 : IsLocallyIncluded(false), isImport(false), isPragmaOnce(false),
128 DirInfo(SrcMgr::C_User), External(false), isModuleHeader(false),
129 isTextualModuleHeader(false), isCompilingModuleHeader(false),
130 Resolved(false), IsValid(false) {}
131
132 /// Retrieve the controlling macro for this header file, if
133 /// any.
134 const IdentifierInfo *
135 getControllingMacro(ExternalPreprocessorSource *External);
136
137 /// Update the module membership bits based on the header role.
138 ///
139 /// isModuleHeader will potentially be set, but not cleared.
140 /// isTextualModuleHeader will be set or cleared based on the role update.
141 void mergeModuleMembership(ModuleMap::ModuleHeaderRole Role);
142};
143
144static_assert(sizeof(HeaderFileInfo) <= 16);
145
146/// An external source of header file information, which may supply
147/// information about header files already included.
148class ExternalHeaderFileInfoSource {
149public:
150 virtual ~ExternalHeaderFileInfoSource();
151
152 /// Retrieve the header file information for the given file entry.
153 ///
154 /// \returns Header file information for the given file entry, with the
155 /// \c External bit set. If the file entry is not known, return a
156 /// default-constructed \c HeaderFileInfo.
157 virtual HeaderFileInfo GetHeaderFileInfo(FileEntryRef FE) = 0;
158};
159
160/// This structure is used to record entries in our framework cache.
161struct FrameworkCacheEntry {
162 /// The directory entry which should be used for the cached framework.
163 OptionalDirectoryEntryRef Directory;
164
165 /// Whether this framework has been "user-specified" to be treated as if it
166 /// were a system framework (even if it was found outside a system framework
167 /// directory).
168 bool IsUserSpecifiedSystemFramework;
169};
170
171namespace detail {
172template <bool Const, typename T>
173using Qualified = std::conditional_t<Const, const T, T>;
174
175/// Forward iterator over the search directories of \c HeaderSearch.
176template <bool IsConst>
177struct SearchDirIteratorImpl
178 : llvm::iterator_facade_base<SearchDirIteratorImpl<IsConst>,
179 std::forward_iterator_tag,
180 Qualified<IsConst, DirectoryLookup>> {
181 /// Const -> non-const iterator conversion.
182 template <typename Enable = std::enable_if<IsConst, bool>>
183 SearchDirIteratorImpl(const SearchDirIteratorImpl<false> &Other)
184 : HS(Other.HS), Idx(Other.Idx) {}
185
186 SearchDirIteratorImpl(const SearchDirIteratorImpl &) = default;
187
188 SearchDirIteratorImpl &operator=(const SearchDirIteratorImpl &) = default;
189
190 bool operator==(const SearchDirIteratorImpl &RHS) const {
191 return HS == RHS.HS && Idx == RHS.Idx;
192 }
193
194 SearchDirIteratorImpl &operator++() {
195 assert(*this && "Invalid iterator.");
196 ++Idx;
197 return *this;
198 }
199
200 Qualified<IsConst, DirectoryLookup> &operator*() const {
201 assert(*this && "Invalid iterator.");
202 return HS->SearchDirs[Idx];
203 }
204
205 /// Creates an invalid iterator.
206 SearchDirIteratorImpl(std::nullptr_t) : HS(nullptr), Idx(0) {}
207
208 /// Checks whether the iterator is valid.
209 explicit operator bool() const { return HS != nullptr; }
210
211private:
212 /// The parent \c HeaderSearch. This is \c nullptr for invalid iterator.
213 Qualified<IsConst, HeaderSearch> *HS;
214
215 /// The index of the current element.
216 size_t Idx;
217
218 /// The constructor that creates a valid iterator.
219 SearchDirIteratorImpl(Qualified<IsConst, HeaderSearch> &HS, size_t Idx)
220 : HS(&HS), Idx(Idx) {}
221
222 /// Only HeaderSearch is allowed to instantiate valid iterators.
223 friend HeaderSearch;
224
225 /// Enables const -> non-const conversion.
226 friend SearchDirIteratorImpl<!IsConst>;
227};
228} // namespace detail
229
230using ConstSearchDirIterator = detail::SearchDirIteratorImpl<true>;
231using SearchDirIterator = detail::SearchDirIteratorImpl<false>;
232
233using ConstSearchDirRange = llvm::iterator_range<ConstSearchDirIterator>;
234using SearchDirRange = llvm::iterator_range<SearchDirIterator>;
235
236/// Encapsulates the information needed to find the file referenced
237/// by a \#include or \#include_next, (sub-)framework lookup, etc.
238class HeaderSearch {
239 friend class DirectoryLookup;
240
241 friend ConstSearchDirIterator;
242 friend SearchDirIterator;
243
244 /// Header-search options used to initialize this header search.
245 const HeaderSearchOptions &HSOpts;
246
247 /// Mapping from SearchDir to HeaderSearchOptions::UserEntries indices.
248 llvm::DenseMap<unsigned, unsigned> SearchDirToHSEntry;
249
250 DiagnosticsEngine &Diags;
251 FileManager &FileMgr;
252
253 /// \#include search path information. Requests for \#include "x" search the
254 /// directory of the \#including file first, then each directory in SearchDirs
255 /// consecutively. Requests for <x> search the current dir first, then each
256 /// directory in SearchDirs, starting at AngledDirIdx, consecutively.
257 std::vector<DirectoryLookup> SearchDirs;
258 /// Whether the DirectoryLookup at the corresponding index in SearchDirs has
259 /// been successfully used to lookup a file.
260 std::vector<bool> SearchDirsUsage;
261 unsigned AngledDirIdx = 0;
262 unsigned SystemDirIdx = 0;
263
264 /// Maps HeaderMap keys to SearchDir indices. When HeaderMaps are used
265 /// heavily, SearchDirs can start with thousands of HeaderMaps, so this Index
266 /// lets us avoid scanning them all to find a match.
267 llvm::StringMap<unsigned, llvm::BumpPtrAllocator> SearchDirHeaderMapIndex;
268
269 /// The index of the first SearchDir that isn't a header map.
270 unsigned FirstNonHeaderMapSearchDirIdx = 0;
271
272 /// \#include prefixes for which the 'system header' property is
273 /// overridden.
274 ///
275 /// For a \#include "x" or \#include \<x> directive, the last string in this
276 /// list which is a prefix of 'x' determines whether the file is treated as
277 /// a system header.
278 std::vector<std::pair<std::string, bool>> SystemHeaderPrefixes;
279
280 /// The context hash used in SpecificModuleCachePath (unless suppressed).
281 std::string ContextHash;
282
283 /// The specific module cache path containing ContextHash (unless suppressed).
284 std::string SpecificModuleCachePath;
285
286 /// The length of the normalized module cache path at the start of \c
287 /// SpecificModuleCachePath.
288 size_t NormalizedModuleCachePathLen = 0;
289
290 /// All the preprocessor-specific data about files that are included.
291 mutable llvm::MapVector<FileEntryRef, HeaderFileInfo> FileInfo;
292
293 /// Keeps track of each lookup performed by LookupFile.
294 struct LookupFileCacheInfo {
295 // The requesting module for the lookup we cached.
296 const Module *RequestingModule = nullptr;
297
298 /// Starting search directory iterator that the cached search was performed
299 /// from. If there is a hit and this value doesn't match the current query,
300 /// the cache has to be ignored.
301 ConstSearchDirIterator StartIt = nullptr;
302
303 /// The search directory iterator that satisfied the query.
304 ConstSearchDirIterator HitIt = nullptr;
305
306 /// This is non-null if the original filename was mapped to a framework
307 /// include via a headermap.
308 const char *MappedName = nullptr;
309
310 /// Default constructor -- Initialize all members with zero.
311 LookupFileCacheInfo() = default;
312
313 void reset(const Module *NewRequestingModule,
314 ConstSearchDirIterator NewStartIt) {
315 RequestingModule = NewRequestingModule;
316 StartIt = NewStartIt;
317 MappedName = nullptr;
318 }
319 };
320 llvm::StringMap<LookupFileCacheInfo, llvm::BumpPtrAllocator> LookupFileCache;
321
322 /// Collection mapping a framework or subframework
323 /// name like "Carbon" to the Carbon.framework directory.
324 llvm::StringMap<FrameworkCacheEntry, llvm::BumpPtrAllocator> FrameworkMap;
325
326 /// Maps include file names (including the quotes or
327 /// angle brackets) to other include file names. This is used to support the
328 /// include_alias pragma for Microsoft compatibility.
329 using IncludeAliasMap =
330 llvm::StringMap<std::string, llvm::BumpPtrAllocator>;
331 std::unique_ptr<IncludeAliasMap> IncludeAliases;
332
333 /// This is a mapping from FileEntry -> HeaderMap, uniquing headermaps.
334 std::vector<std::pair<FileEntryRef, std::unique_ptr<HeaderMap>>> HeaderMaps;
335
336 /// The mapping between modules and headers.
337 mutable ModuleMap ModMap;
338
339 struct ModuleMapDirectoryState {
340 OptionalFileEntryRef ModuleMapFile;
341 OptionalFileEntryRef PrivateModuleMapFile;
342 enum {
343 Parsed,
344 Loaded,
345 Invalid,
346 } Status;
347
348 /// Relative header path -> list of module names
349 llvm::StringMap<llvm::SmallVector<StringRef, 1>> HeaderToModules{};
350 /// Relative dir path -> module name
351 llvm::SmallVector<std::pair<std::string, StringRef>, 2>
352 UmbrellaDirModules{};
353 /// List of module names with umbrella header decls
354 llvm::SmallVector<StringRef, 2> UmbrellaHeaderModules{};
355 };
356
357 /// Describes whether a given directory has a module map in it.
358 llvm::DenseMap<const DirectoryEntry *, ModuleMapDirectoryState>
359 DirectoryModuleMap;
360
361 /// Set of module map files we've already loaded, and a flag indicating
362 /// whether they were valid or not.
363 llvm::DenseMap<const FileEntry *, bool> LoadedModuleMaps;
364
365 /// Set of module map files we've already parsed, and a flag indicating
366 /// whether they were valid or not.
367 llvm::DenseMap<const FileEntry *, bool> ParsedModuleMaps;
368
369 // A map of discovered headers with their associated include file name.
370 llvm::DenseMap<const FileEntry *, llvm::SmallString<64>> IncludeNames;
371
372 /// Uniqued set of framework names, which is used to track which
373 /// headers were included as framework headers.
374 llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames;
375
376 /// Entity used to resolve the identifier IDs of controlling
377 /// macros into IdentifierInfo pointers, and keep the identifire up to date,
378 /// as needed.
379 ExternalPreprocessorSource *ExternalLookup = nullptr;
380
381 /// Entity used to look up stored header file information.
382 ExternalHeaderFileInfoSource *ExternalSource = nullptr;
383
384 /// Scan all of the header maps at the beginning of SearchDirs and
385 /// map their keys to the SearchDir index of their header map.
386 void indexInitialHeaderMaps();
387
388 /// Build the module map index for a directory's module map.
389 ///
390 /// This fills a ModuleMapDirectoryState with index information from its
391 /// directory's module map.
392 void buildModuleMapIndex(DirectoryEntryRef Dir,
393 ModuleMapDirectoryState &MMState);
394
395 void processModuleMapForIndex(const modulemap::ModuleMapFile &MMF,
396 DirectoryEntryRef MMDir, StringRef PathPrefix,
397 ModuleMapDirectoryState &MMState);
398
399 void processExternModuleDeclForIndex(const modulemap::ExternModuleDecl &EMD,
400 DirectoryEntryRef MMDir,
401 StringRef PathPrefix,
402 ModuleMapDirectoryState &MMState);
403
404 void processModuleDeclForIndex(const modulemap::ModuleDecl &MD,
405 StringRef ModuleName, DirectoryEntryRef MMDir,
406 StringRef PathPrefix,
407 ModuleMapDirectoryState &MMState);
408
409 void addToModuleMapIndex(StringRef RelPath, StringRef ModuleName,
410 StringRef PathPrefix,
411 ModuleMapDirectoryState &MMState);
412
413 /// Check if a relative path would be covered by the module map index.
414 /// Returns the module names that would cover this path.
415 SmallVector<StringRef, 1>
416 findMatchingModulesInIndex(StringRef RelativePath,
417 const ModuleMapDirectoryState &MMState) const;
418
419public:
420 HeaderSearch(const HeaderSearchOptions &HSOpts, SourceManager &SourceMgr,
421 DiagnosticsEngine &Diags, const LangOptions &LangOpts,
422 const TargetInfo *Target);
423 HeaderSearch(const HeaderSearch &) = delete;
424 HeaderSearch &operator=(const HeaderSearch &) = delete;
425
426 /// Retrieve the header-search options with which this header search
427 /// was initialized.
428 const HeaderSearchOptions &getHeaderSearchOpts() const { return HSOpts; }
429
430 FileManager &getFileMgr() const { return FileMgr; }
431
432 DiagnosticsEngine &getDiags() const { return Diags; }
433
434 /// Interface for setting the file search paths.
435 void SetSearchPaths(std::vector<DirectoryLookup> dirs, unsigned angledDirIdx,
436 unsigned systemDirIdx,
437 llvm::DenseMap<unsigned, unsigned> searchDirToHSEntry);
438
439 /// Add an additional search path.
440 void AddSearchPath(const DirectoryLookup &dir, bool isAngled);
441
442 /// Add an additional system search path.
443 void AddSystemSearchPath(const DirectoryLookup &dir) {
444 SearchDirs.push_back(x: dir);
445 SearchDirsUsage.push_back(x: false);
446 }
447
448 /// Set the list of system header prefixes.
449 void SetSystemHeaderPrefixes(ArrayRef<std::pair<std::string, bool>> P) {
450 SystemHeaderPrefixes.assign(first: P.begin(), last: P.end());
451 }
452
453 /// Checks whether the map exists or not.
454 bool HasIncludeAliasMap() const { return (bool)IncludeAliases; }
455
456 /// Map the source include name to the dest include name.
457 ///
458 /// The Source should include the angle brackets or quotes, the dest
459 /// should not. This allows for distinction between <> and "" headers.
460 void AddIncludeAlias(StringRef Source, StringRef Dest) {
461 if (!IncludeAliases)
462 IncludeAliases.reset(p: new IncludeAliasMap);
463 (*IncludeAliases)[Source] = std::string(Dest);
464 }
465
466 /// Maps one header file name to a different header
467 /// file name, for use with the include_alias pragma. Note that the source
468 /// file name should include the angle brackets or quotes. Returns StringRef
469 /// as null if the header cannot be mapped.
470 StringRef MapHeaderToIncludeAlias(StringRef Source) {
471 assert(IncludeAliases && "Trying to map headers when there's no map");
472
473 // Do any filename replacements before anything else
474 IncludeAliasMap::const_iterator Iter = IncludeAliases->find(Key: Source);
475 if (Iter != IncludeAliases->end())
476 return Iter->second;
477 return {};
478 }
479
480 /// Initialize the module cache path.
481 void initializeModuleCachePath(std::string ContextHash);
482
483 /// Retrieve the specific module cache path. This is the normalized module
484 /// cache path plus the context hash (unless suppressed).
485 StringRef getSpecificModuleCachePath() const {
486 return SpecificModuleCachePath;
487 }
488
489 /// Retrieve the context hash.
490 StringRef getContextHash() const { return ContextHash; }
491
492 /// Retrieve the normalized module cache path. This is the path as provided on
493 /// the command line, but absolute, without './' components, and with
494 /// preferred path separators. Note that this does not have the context hash.
495 StringRef getNormalizedModuleCachePath() const {
496 return getSpecificModuleCachePath().substr(Start: 0, N: NormalizedModuleCachePathLen);
497 }
498
499 /// Forget everything we know about headers so far.
500 void ClearFileInfo() {
501 FileInfo.clear();
502 }
503
504 void SetExternalLookup(ExternalPreprocessorSource *EPS) {
505 ExternalLookup = EPS;
506 }
507
508 ExternalPreprocessorSource *getExternalLookup() const {
509 return ExternalLookup;
510 }
511
512 /// Set the external source of header information.
513 void SetExternalSource(ExternalHeaderFileInfoSource *ES) {
514 ExternalSource = ES;
515 }
516
517 void diagnoseHeaderShadowing(
518 StringRef Filename, OptionalFileEntryRef FE, bool &DiagnosedShadowing,
519 SourceLocation IncludeLoc, ConstSearchDirIterator FromDir,
520 ArrayRef<std::pair<OptionalFileEntryRef, DirectoryEntryRef>> Includers,
521 bool isAngled, int IncluderLoopIndex, ConstSearchDirIterator MainLoopIt);
522
523 /// Set the target information for the header search, if not
524 /// already known.
525 void setTarget(const TargetInfo &Target);
526
527 /// Given a "foo" or \<foo> reference, look up the indicated file,
528 /// return null on failure.
529 ///
530 /// \returns If successful, this returns 'UsedDir', the DirectoryLookup member
531 /// the file was found in, or null if not applicable.
532 ///
533 /// \param IncludeLoc Used for diagnostics if valid.
534 ///
535 /// \param isAngled indicates whether the file reference is a <> reference.
536 ///
537 /// \param CurDir If non-null, the file was found in the specified directory
538 /// search location. This is used to implement \#include_next.
539 ///
540 /// \param Includers Indicates where the \#including file(s) are, in case
541 /// relative searches are needed. In reverse order of inclusion.
542 ///
543 /// \param SearchPath If non-null, will be set to the search path relative
544 /// to which the file was found. If the include path is absolute, SearchPath
545 /// will be set to an empty string.
546 ///
547 /// \param RelativePath If non-null, will be set to the path relative to
548 /// SearchPath at which the file was found. This only differs from the
549 /// Filename for framework includes.
550 ///
551 /// \param SuggestedModule If non-null, and the file found is semantically
552 /// part of a known module, this will be set to the module that should
553 /// be imported instead of preprocessing/parsing the file found.
554 ///
555 /// \param IsMapped If non-null, and the search involved header maps, set to
556 /// true.
557 ///
558 /// \param IsFrameworkFound If non-null, will be set to true if a framework is
559 /// found in any of searched SearchDirs. Will be set to false if a framework
560 /// is found only through header maps. Doesn't guarantee the requested file is
561 /// found.
562 OptionalFileEntryRef LookupFile(
563 StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
564 ConstSearchDirIterator FromDir, ConstSearchDirIterator *CurDir,
565 ArrayRef<std::pair<OptionalFileEntryRef, DirectoryEntryRef>> Includers,
566 SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
567 Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
568 bool *IsMapped, bool *IsFrameworkFound, bool SkipCache = false,
569 bool BuildSystemModule = false, bool OpenFile = true,
570 bool CacheFailures = true);
571
572 /// Look up a subframework for the specified \#include file.
573 ///
574 /// For example, if \#include'ing <HIToolbox/HIToolbox.h> from
575 /// within ".../Carbon.framework/Headers/Carbon.h", check to see if
576 /// HIToolbox is a subframework within Carbon.framework. If so, return
577 /// the FileEntry for the designated file, otherwise return null.
578 OptionalFileEntryRef LookupSubframeworkHeader(
579 StringRef Filename, FileEntryRef ContextFileEnt,
580 SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
581 Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule);
582
583 /// Look up the specified framework name in our framework cache.
584 /// \returns The DirectoryEntry it is in if we know, null otherwise.
585 FrameworkCacheEntry &LookupFrameworkCache(StringRef FWName) {
586 return FrameworkMap[FWName];
587 }
588
589 /// Mark the specified file as a target of a \#include,
590 /// \#include_next, or \#import directive.
591 ///
592 /// \return false if \#including the file will have no effect or true
593 /// if we should include it.
594 ///
595 /// \param M The module to which `File` belongs (this should usually be the
596 /// SuggestedModule returned by LookupFile/LookupSubframeworkHeader)
597 bool ShouldEnterIncludeFile(Preprocessor &PP, FileEntryRef File,
598 bool isImport, bool ModulesEnabled, Module *M,
599 bool &IsFirstIncludeOfFile);
600
601 /// Return whether the specified file is a normal header,
602 /// a system header, or a C++ friendly system header.
603 SrcMgr::CharacteristicKind getFileDirFlavor(FileEntryRef File) {
604 if (const HeaderFileInfo *HFI = getExistingFileInfo(FE: File))
605 return (SrcMgr::CharacteristicKind)HFI->DirInfo;
606 return (SrcMgr::CharacteristicKind)HeaderFileInfo().DirInfo;
607 }
608
609 /// Mark the specified file as a "once only" file due to
610 /// \#pragma once.
611 void MarkFileIncludeOnce(FileEntryRef File) {
612 getFileInfo(FE: File).isPragmaOnce = true;
613 }
614
615 /// Mark the specified file as a system header, e.g. due to
616 /// \#pragma GCC system_header.
617 void MarkFileSystemHeader(FileEntryRef File) {
618 getFileInfo(FE: File).DirInfo = SrcMgr::C_System;
619 }
620
621 /// Mark the specified file as part of a module.
622 void MarkFileModuleHeader(FileEntryRef FE, ModuleMap::ModuleHeaderRole Role,
623 bool isCompilingModuleHeader);
624
625 /// Mark the specified file as having a controlling macro.
626 ///
627 /// This is used by the multiple-include optimization to eliminate
628 /// no-op \#includes.
629 void SetFileControllingMacro(FileEntryRef File,
630 const IdentifierInfo *ControllingMacro) {
631 getFileInfo(FE: File).LazyControllingMacro = ControllingMacro;
632 }
633
634 /// Determine whether this file is intended to be safe from
635 /// multiple inclusions, e.g., it has \#pragma once or a controlling
636 /// macro.
637 ///
638 /// This routine does not consider the effect of \#import
639 bool isFileMultipleIncludeGuarded(FileEntryRef File) const;
640
641 /// Determine whether the given file is known to have ever been \#imported.
642 bool hasFileBeenImported(FileEntryRef File) const {
643 const HeaderFileInfo *FI = getExistingFileInfo(FE: File);
644 return FI && FI->isImport;
645 }
646
647 /// Determine which HeaderSearchOptions::UserEntries have been successfully
648 /// used so far and mark their index with 'true' in the resulting bit vector.
649 /// Note: implicit module maps don't contribute to entry usage.
650 std::vector<bool> computeUserEntryUsage() const;
651
652 /// Collect which HeaderSearchOptions::VFSOverlayFiles have been meaningfully
653 /// used so far and mark their index with 'true' in the resulting bit vector.
654 ///
655 /// Note: this ignores VFSs that redirect non-affecting files such as unused
656 /// modulemaps.
657 std::vector<bool> collectVFSUsageAndClear() const;
658
659 /// This method returns a HeaderMap for the specified
660 /// FileEntry, uniquing them through the 'HeaderMaps' datastructure.
661 const HeaderMap *CreateHeaderMap(FileEntryRef FE);
662
663 /// Get filenames for all registered header maps.
664 void getHeaderMapFileNames(SmallVectorImpl<std::string> &Names) const;
665
666 /// Retrieve the name of the cached module file that should be used
667 /// to load the given module.
668 ///
669 /// \param Module The module whose module file name will be returned.
670 ///
671 /// \returns The name of the module file that corresponds to this module,
672 /// or an empty string if this module does not correspond to any module file.
673 ModuleFileName getCachedModuleFileName(Module *Module);
674
675 /// Retrieve the name of the prebuilt module file that should be used
676 /// to load a module with the given name.
677 ///
678 /// \param ModuleName The module whose module file name will be returned.
679 ///
680 /// \param FileMapOnly If true, then only look in the explicit module name
681 // to file name map and skip the directory search.
682 ///
683 /// \returns The name of the module file that corresponds to this module,
684 /// or an empty string if this module does not correspond to any module file.
685 ModuleFileName getPrebuiltModuleFileName(StringRef ModuleName,
686 bool FileMapOnly = false);
687
688 /// Retrieve the name of the prebuilt module file that should be used
689 /// to load the given module.
690 ///
691 /// \param Module The module whose module file name will be returned.
692 ///
693 /// \returns The name of the module file that corresponds to this module,
694 /// or an empty string if this module does not correspond to any module file.
695 ModuleFileName getPrebuiltImplicitModuleFileName(Module *Module);
696
697 /// Retrieve the name of the (to-be-)cached module file that should
698 /// be used to load a module with the given name.
699 ///
700 /// \param ModuleName The module whose module file name will be returned.
701 ///
702 /// \param ModuleMapPath A path that when combined with \c ModuleName
703 /// uniquely identifies this module. See Module::ModuleMap.
704 ///
705 /// \returns The name of the module file that corresponds to this module,
706 /// or an empty string if this module does not correspond to any module file.
707 ModuleFileName getCachedModuleFileName(StringRef ModuleName,
708 StringRef ModuleMapPath);
709
710 /// Lookup a module Search for a module with the given name.
711 ///
712 /// \param ModuleName The name of the module we're looking for.
713 ///
714 /// \param ImportLoc Location of the module include/import.
715 ///
716 /// \param AllowSearch Whether we are allowed to search in the various
717 /// search directories to produce a module definition. If not, this lookup
718 /// will only return an already-known module.
719 ///
720 /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
721 /// in subdirectories.
722 ///
723 /// \returns The module with the given name.
724 Module *lookupModule(StringRef ModuleName,
725 SourceLocation ImportLoc = SourceLocation(),
726 bool AllowSearch = true,
727 bool AllowExtraModuleMapSearch = false);
728
729 /// Try to find a module map file in the given directory, returning
730 /// \c nullopt if none is found.
731 OptionalFileEntryRef lookupModuleMapFile(DirectoryEntryRef Dir,
732 bool IsFramework);
733
734 /// Determine whether there is a module map that may map the header
735 /// with the given file name to a (sub)module.
736 /// Always returns false if modules are disabled.
737 ///
738 /// \param Filename The name of the file.
739 ///
740 /// \param Root The "root" directory, at which we should stop looking for
741 /// module maps.
742 ///
743 /// \param IsSystem Whether the directories we're looking at are system
744 /// header directories.
745 bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root,
746 bool IsSystem);
747
748 /// Retrieve the module that corresponds to the given file, if any.
749 ///
750 /// \param File The header that we wish to map to a module.
751 /// \param AllowTextual Whether we want to find textual headers too.
752 ModuleMap::KnownHeader findModuleForHeader(FileEntryRef File,
753 bool AllowTextual = false,
754 bool AllowExcluded = false) const;
755
756 /// Retrieve all the modules corresponding to the given file.
757 ///
758 /// \ref findModuleForHeader should typically be used instead of this.
759 ArrayRef<ModuleMap::KnownHeader>
760 findAllModulesForHeader(FileEntryRef File) const;
761
762 /// Like \ref findAllModulesForHeader, but do not attempt to infer module
763 /// ownership from umbrella headers if we've not already done so.
764 ArrayRef<ModuleMap::KnownHeader>
765 findResolvedModulesForHeader(FileEntryRef File) const;
766
767 /// Read the contents of the given module map file.
768 ///
769 /// \param File The module map file.
770 /// \param IsSystem Whether this file is in a system header directory.
771 /// \param ImplicitlyDiscovered Whether this file was found by module map
772 /// search.
773 /// \param ID If the module map file is already mapped (perhaps as part of
774 /// processing a preprocessed module), the ID of the file.
775 /// \param Offset [inout] An offset within ID to start parsing. On exit,
776 /// filled by the end of the parsed contents (either EOF or the
777 /// location of an end-of-module-map pragma).
778 /// \param OriginalModuleMapFile The original path to the module map file,
779 /// used to resolve paths within the module (this is required when
780 /// building the module from preprocessed source).
781 /// \returns true if an error occurred, false otherwise.
782 bool parseAndLoadModuleMapFile(FileEntryRef File, bool IsSystem,
783 bool ImplicitlyDiscovered,
784 FileID ID = FileID(),
785 unsigned *Offset = nullptr,
786 StringRef OriginalModuleMapFile = StringRef());
787
788 /// Collect the set of all known, top-level modules.
789 ///
790 /// \param Modules Will be filled with the set of known, top-level modules.
791 void collectAllModules(SmallVectorImpl<Module *> &Modules);
792
793 /// Load all known, top-level system modules.
794 void loadTopLevelSystemModules();
795
796private:
797 /// Lookup a module with the given module name and search-name.
798 ///
799 /// \param ModuleName The name of the module we're looking for.
800 ///
801 /// \param SearchName The "search-name" to derive filesystem paths from
802 /// when looking for the module map; this is usually equal to ModuleName,
803 /// but for compatibility with some buggy frameworks, additional attempts
804 /// may be made to find the module under a related-but-different search-name.
805 ///
806 /// \param ImportLoc Location of the module include/import.
807 ///
808 /// \param AllowExtraModuleMapSearch Whether we allow to search modulemaps
809 /// in subdirectories.
810 ///
811 /// \returns The module named ModuleName.
812 Module *lookupModule(StringRef ModuleName, StringRef SearchName,
813 SourceLocation ImportLoc,
814 bool AllowExtraModuleMapSearch = false);
815
816 /// Retrieve the name of the (to-be-)cached module file that should
817 /// be used to load a module with the given name.
818 ///
819 /// \param ModuleName The module whose module file name will be returned.
820 ///
821 /// \param ModuleMapPath A path that when combined with \c ModuleName
822 /// uniquely identifies this module. See Module::ModuleMap.
823 ///
824 /// \param NormalizedCachePath The normalized path to the module cache.
825 ///
826 /// \returns The name of the module file that corresponds to this module,
827 /// or an empty string if this module does not correspond to any module file.
828 ModuleFileName getCachedModuleFileNameImpl(StringRef ModuleName,
829 StringRef ModuleMapPath,
830 StringRef NormalizedCachePath);
831
832 /// Retrieve a module with the given name, which may be part of the
833 /// given framework.
834 ///
835 /// \param Name The name of the module to retrieve.
836 ///
837 /// \param Dir The framework directory (e.g., ModuleName.framework).
838 ///
839 /// \param IsSystem Whether the framework directory is part of the system
840 /// frameworks.
841 ///
842 /// \param ImplicitlyDiscovered Whether the framework was discovered by module
843 /// map search.
844 ///
845 /// \returns The module, if found; otherwise, null.
846 Module *loadFrameworkModule(StringRef Name, DirectoryEntryRef Dir,
847 bool IsSystem, bool ImplicitlyDiscovered);
848
849 /// Load all of the module maps within the immediate subdirectories
850 /// of the given search directory.
851 void loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir);
852
853 /// Diagnose headers that are a symlink and not covered by a module map.
854 void diagnoseUncoveredSymlink(FileEntryRef File,
855 ModuleMap::KnownHeader &Module,
856 const DirectoryEntry *Root);
857
858 /// Find and suggest a usable module for the given file.
859 ///
860 /// \return \c true if the file can be used, \c false if we are not permitted to
861 /// find this file due to requirements from \p RequestingModule.
862 bool findUsableModuleForHeader(FileEntryRef File, const DirectoryEntry *Root,
863 Module *RequestingModule,
864 ModuleMap::KnownHeader *SuggestedModule,
865 bool IsSystemHeaderDir);
866
867 /// Find and suggest a usable module for the given file, which is part of
868 /// the specified framework.
869 ///
870 /// \return \c true if the file can be used, \c false if we are not permitted to
871 /// find this file due to requirements from \p RequestingModule.
872 bool findUsableModuleForFrameworkHeader(
873 FileEntryRef File, StringRef FrameworkName, Module *RequestingModule,
874 ModuleMap::KnownHeader *SuggestedModule, bool IsSystemFramework);
875
876 /// Look up the file with the specified name and determine its owning
877 /// module.
878 OptionalFileEntryRef
879 getFileAndSuggestModule(StringRef FileName, SourceLocation IncludeLoc,
880 const DirectoryEntry *Dir, bool IsSystemHeaderDir,
881 Module *RequestingModule,
882 ModuleMap::KnownHeader *SuggestedModule,
883 bool OpenFile = true, bool CacheFailures = true);
884
885 /// Cache the result of a successful lookup at the given include location
886 /// using the search path at \c HitIt.
887 void cacheLookupSuccess(LookupFileCacheInfo &CacheLookup,
888 ConstSearchDirIterator HitIt,
889 SourceLocation IncludeLoc);
890
891 /// Note that a lookup at the given include location was successful using the
892 /// search path at index `HitIdx`.
893 void noteLookupUsage(unsigned HitIdx, SourceLocation IncludeLoc);
894
895public:
896 /// Retrieve the module map.
897 ModuleMap &getModuleMap() { return ModMap; }
898
899 /// Retrieve the module map.
900 const ModuleMap &getModuleMap() const { return ModMap; }
901
902 /// Return the HeaderFileInfo structure for the specified FileEntry, in
903 /// preparation for updating it in some way.
904 HeaderFileInfo &getFileInfo(FileEntryRef FE);
905
906 /// Return the HeaderFileInfo structure for the specified FileEntry, if it has
907 /// ever been filled in (either locally or externally).
908 const HeaderFileInfo *getExistingFileInfo(FileEntryRef FE) const;
909
910 /// Iterate HeaderFileInfo structures and their corresponding FileEntryRef, if
911 /// they have ever been filled in locally.
912 void forEachExistingLocalFileInfo(
913 llvm::function_ref<void(FileEntryRef, const HeaderFileInfo &)> Fn) const;
914
915 SearchDirIterator search_dir_begin() { return {*this, 0}; }
916 SearchDirIterator search_dir_end() { return {*this, SearchDirs.size()}; }
917 SearchDirRange search_dir_range() {
918 return {search_dir_begin(), search_dir_end()};
919 }
920
921 ConstSearchDirIterator search_dir_begin() const { return quoted_dir_begin(); }
922 ConstSearchDirIterator search_dir_nth(size_t n) const {
923 assert(n < SearchDirs.size());
924 return {*this, n};
925 }
926 ConstSearchDirIterator search_dir_end() const { return system_dir_end(); }
927 ConstSearchDirRange search_dir_range() const {
928 return {search_dir_begin(), search_dir_end()};
929 }
930
931 unsigned search_dir_size() const { return SearchDirs.size(); }
932
933 ConstSearchDirIterator quoted_dir_begin() const { return {*this, 0}; }
934 ConstSearchDirIterator quoted_dir_end() const { return angled_dir_begin(); }
935
936 ConstSearchDirIterator angled_dir_begin() const {
937 return {*this, AngledDirIdx};
938 }
939 ConstSearchDirIterator angled_dir_end() const { return system_dir_begin(); }
940
941 ConstSearchDirIterator system_dir_begin() const {
942 return {*this, SystemDirIdx};
943 }
944 ConstSearchDirIterator system_dir_end() const {
945 return {*this, SearchDirs.size()};
946 }
947
948 /// Get the index of the given search directory.
949 unsigned searchDirIdx(const DirectoryLookup &DL) const;
950
951 /// Retrieve a uniqued framework name.
952 StringRef getUniqueFrameworkName(StringRef Framework);
953
954 /// Retrieve the include name for the header.
955 ///
956 /// \param File The entry for a given header.
957 /// \returns The name of how the file was included when the header's location
958 /// was resolved.
959 StringRef getIncludeNameForHeader(const FileEntry *File) const;
960
961 /// Suggest a path by which the specified file could be found, for use in
962 /// diagnostics to suggest a #include. Returned path will only contain forward
963 /// slashes as separators. MainFile is the absolute path of the file that we
964 /// are generating the diagnostics for. It will try to shorten the path using
965 /// MainFile location, if none of the include search directories were prefix
966 /// of File.
967 ///
968 /// \param IsAngled If non-null, filled in to indicate whether the suggested
969 /// path should be referenced as <Header.h> instead of "Header.h".
970 std::string suggestPathToFileForDiagnostics(FileEntryRef File,
971 llvm::StringRef MainFile,
972 bool *IsAngled = nullptr) const;
973
974 /// Suggest a path by which the specified file could be found, for use in
975 /// diagnostics to suggest a #include. Returned path will only contain forward
976 /// slashes as separators. MainFile is the absolute path of the file that we
977 /// are generating the diagnostics for. It will try to shorten the path using
978 /// MainFile location, if none of the include search directories were prefix
979 /// of File.
980 ///
981 /// \param WorkingDir If non-empty, this will be prepended to search directory
982 /// paths that are relative.
983 std::string suggestPathToFileForDiagnostics(llvm::StringRef File,
984 llvm::StringRef WorkingDir,
985 llvm::StringRef MainFile,
986 bool *IsAngled = nullptr) const;
987
988 void PrintStats();
989
990 size_t getTotalMemory() const;
991
992private:
993 /// Describes what happened when we tried to load or parse a module map file.
994 enum ModuleMapResult {
995 /// The module map file had already been processed.
996 MMR_AlreadyProcessed,
997
998 /// The module map file was processed by this invocation.
999 MMR_NewlyProcessed,
1000
1001 /// There is was directory with the given name.
1002 MMR_NoDirectory,
1003
1004 /// There was either no module map file or the module map file was
1005 /// invalid.
1006 MMR_InvalidModuleMap
1007 };
1008
1009 ModuleMapResult parseAndLoadModuleMapFileImpl(
1010 FileEntryRef File, bool IsSystem, bool ImplicitlyDiscovered,
1011 DirectoryEntryRef Dir, FileID ID = FileID(), unsigned *Offset = nullptr,
1012 bool DiagnosePrivMMap = false);
1013
1014 ModuleMapResult parseModuleMapFileImpl(FileEntryRef File, bool IsSystem,
1015 bool ImplicitlyDiscovered,
1016 DirectoryEntryRef Dir,
1017 FileID ID = FileID());
1018
1019 /// Try to load the module map file in the given directory.
1020 ///
1021 /// \param DirName The name of the directory where we will look for a module
1022 /// map file.
1023 /// \param IsSystem Whether this is a system header directory.
1024 /// \param IsFramework Whether this is a framework directory.
1025 ///
1026 /// \returns The result of attempting to load the module map file from the
1027 /// named directory.
1028 ModuleMapResult parseAndLoadModuleMapFile(StringRef DirName, bool IsSystem,
1029 bool ImplicitlyDiscovered,
1030 bool IsFramework);
1031
1032 /// Try to load the module map file in the given directory.
1033 ///
1034 /// \param Dir The directory where we will look for a module map file.
1035 /// \param IsSystem Whether this is a system header directory.
1036 /// \param IsFramework Whether this is a framework directory.
1037 ///
1038 /// \returns The result of attempting to load the module map file from the
1039 /// named directory.
1040 ModuleMapResult parseAndLoadModuleMapFile(DirectoryEntryRef Dir,
1041 bool IsSystem,
1042 bool ImplicitlyDiscovered,
1043 bool IsFramework);
1044
1045 ModuleMapResult parseModuleMapFile(StringRef DirName, bool IsSystem,
1046 bool ImplicitlyDiscovered,
1047 bool IsFramework);
1048 ModuleMapResult parseModuleMapFile(DirectoryEntryRef Dir, bool IsSystem,
1049 bool ImplicitlyDiscovered,
1050 bool IsFramework);
1051};
1052
1053/// Apply the header search options to get given HeaderSearch object.
1054void ApplyHeaderSearchOptions(HeaderSearch &HS,
1055 const HeaderSearchOptions &HSOpts,
1056 const LangOptions &Lang,
1057 const llvm::Triple &triple);
1058
1059void normalizeModuleCachePath(FileManager &FileMgr, StringRef Path,
1060 SmallVectorImpl<char> &NormalizedPath);
1061
1062std::string createSpecificModuleCachePath(FileManager &FileMgr,
1063 StringRef ModuleCachePath,
1064 bool DisableModuleHash,
1065 std::string ContextHash);
1066
1067} // namespace clang
1068
1069#endif // LLVM_CLANG_LEX_HEADERSEARCH_H
1070