//===--- HeaderSearch.cpp - Resolve Header File Locations ---===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the DirectoryLookup and HeaderSearch interfaces. // //===----------------------------------------------------------------------===// #include "clang/Lex/HeaderSearch.h" #include "clang/Basic/FileManager.h" #include "clang/Basic/IdentifierTable.h" #include "clang/Lex/ExternalPreprocessorSource.h" #include "clang/Lex/HeaderMap.h" #include "clang/Lex/HeaderSearchOptions.h" #include "clang/Lex/LexDiagnostic.h" #include "clang/Lex/Lexer.h" #include "clang/Lex/Preprocessor.h" #include "llvm/ADT/APInt.h" #include "llvm/ADT/Hashing.h" #include "llvm/ADT/SmallString.h" #include "llvm/Support/Capacity.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/Path.h" #include "llvm/Support/raw_ostream.h" #include <cstdio> #include <utility> #if defined(LLVM_ON_UNIX) #include <limits.h> #endif using namespace clang; const IdentifierInfo * HeaderFileInfo::getControllingMacro(ExternalPreprocessorSource *External) { if (ControllingMacro) { if (ControllingMacro->isOutOfDate()) External->updateOutOfDateIdentifier( *const_cast<IdentifierInfo *>(ControllingMacro)); return ControllingMacro; } if (!ControllingMacroID || !External) return nullptr; ControllingMacro = External->GetIdentifier(ControllingMacroID); return ControllingMacro; } ExternalHeaderFileInfoSource::~ExternalHeaderFileInfoSource() {} HeaderSearch::HeaderSearch(IntrusiveRefCntPtr<HeaderSearchOptions> HSOpts, SourceManager &SourceMgr, DiagnosticsEngine &Diags, const LangOptions &LangOpts, const TargetInfo *Target) : HSOpts(std::move(HSOpts)), Diags(Diags), FileMgr(SourceMgr.getFileManager()), FrameworkMap(64), ModMap(SourceMgr, Diags, LangOpts, Target, *this) { AngledDirIdx = 0; SystemDirIdx = 0; NoCurDirSearch = false; ExternalLookup = nullptr; ExternalSource = nullptr; NumIncluded = 0; NumMultiIncludeFileOptzn = 0; NumFrameworkLookups = NumSubFrameworkLookups = 0; } HeaderSearch::~HeaderSearch() { // Delete headermaps. for (unsigned i = 0, e = HeaderMaps.size(); i != e; ++i) delete HeaderMaps[i].second; } void HeaderSearch::PrintStats() { fprintf(stderr, "\n*** HeaderSearch Stats:\n"); fprintf(stderr, "%d files tracked.\n", (int)FileInfo.size()); unsigned NumOnceOnlyFiles = 0, MaxNumIncludes = 0, NumSingleIncludedFiles = 0; for (unsigned i = 0, e = FileInfo.size(); i != e; ++i) { NumOnceOnlyFiles += FileInfo[i].isImport; if (MaxNumIncludes < FileInfo[i].NumIncludes) MaxNumIncludes = FileInfo[i].NumIncludes; NumSingleIncludedFiles += FileInfo[i].NumIncludes == 1; } fprintf(stderr, " %d #import/#pragma once files.\n", NumOnceOnlyFiles); fprintf(stderr, " %d included exactly once.\n", NumSingleIncludedFiles); fprintf(stderr, " %d max times a file is included.\n", MaxNumIncludes); fprintf(stderr, " %d #include/#include_next/#import.\n", NumIncluded); fprintf(stderr, " %d #includes skipped due to" " the multi-include optimization.\n", NumMultiIncludeFileOptzn); fprintf(stderr, "%d framework lookups.\n", NumFrameworkLookups); fprintf(stderr, "%d subframework lookups.\n", NumSubFrameworkLookups); } /// CreateHeaderMap - This method returns a HeaderMap for the specified /// FileEntry, uniquing them through the 'HeaderMaps' datastructure. const HeaderMap *HeaderSearch::CreateHeaderMap(const FileEntry *FE) { // We expect the number of headermaps to be small, and almost always empty. // If it ever grows, use of a linear search should be re-evaluated. if (!HeaderMaps.empty()) { for (unsigned i = 0, e = HeaderMaps.size(); i != e; ++i) // Pointer equality comparison of FileEntries works because they are // already uniqued by inode. if (HeaderMaps[i].first == FE) return HeaderMaps[i].second; } if (const HeaderMap *HM = HeaderMap::Create(FE, FileMgr)) { HeaderMaps.push_back(std::make_pair(FE, HM)); return HM; } return nullptr; } std::string HeaderSearch::getModuleFileName(Module *Module) { const FileEntry *ModuleMap = getModuleMap().getModuleMapFileForUniquing(Module); return getModuleFileName(Module->Name, ModuleMap->getName()); } std::string HeaderSearch::getModuleFileName(StringRef ModuleName, StringRef ModuleMapPath) { // If we don't have a module cache path or aren't supposed to use one, we // can't do anything. if (getModuleCachePath().empty()) return std::string(); SmallString<256> Result(getModuleCachePath()); llvm::sys::fs::make_absolute(Result); if (HSOpts->DisableModuleHash) { llvm::sys::path::append(Result, ModuleName + ".pcm"); } else { // Construct the name <ModuleName>-<hash of ModuleMapPath>.pcm which should // ideally be globally unique to this particular module. Name collisions // in the hash are safe (because any translation unit can only import one // module with each name), but result in a loss of caching. // // To avoid false-negatives, we form as canonical a path as we can, and map // to lower-case in case we're on a case-insensitive file system. auto *Dir = FileMgr.getDirectory(llvm::sys::path::parent_path(ModuleMapPath)); if (!Dir) return std::string(); auto DirName = FileMgr.getCanonicalName(Dir); auto FileName = llvm::sys::path::filename(ModuleMapPath); llvm::hash_code Hash = llvm::hash_combine(DirName.lower(), FileName.lower()); SmallString<128> HashStr; llvm::APInt(64, size_t(Hash)).toStringUnsigned(HashStr, /*Radix*/36); llvm::sys::path::append(Result, ModuleName + "-" + HashStr + ".pcm"); } return Result.str().str(); } Module *HeaderSearch::lookupModule(StringRef ModuleName, bool AllowSearch) { // Look in the module map to determine if there is a module by this name. Module *Module = ModMap.findModule(ModuleName); if (Module || !AllowSearch || !HSOpts->ImplicitModuleMaps) return Module; // Look through the various header search paths to load any available module // maps, searching for a module map that describes this module. for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) { if (SearchDirs[Idx].isFramework()) { // Search for or infer a module map for a framework. SmallString<128> FrameworkDirName; FrameworkDirName += SearchDirs[Idx].getFrameworkDir()->getName(); llvm::sys::path::append(FrameworkDirName, ModuleName + ".framework"); if (const DirectoryEntry *FrameworkDir = FileMgr.getDirectory(FrameworkDirName)) { bool IsSystem = SearchDirs[Idx].getDirCharacteristic() != SrcMgr::C_User; Module = loadFrameworkModule(ModuleName, FrameworkDir, IsSystem); if (Module) break; } } // FIXME: Figure out how header maps and module maps will work together. // Only deal with normal search directories. if (!SearchDirs[Idx].isNormalDir()) continue; bool IsSystem = SearchDirs[Idx].isSystemHeaderDirectory(); // Search for a module map file in this directory. if (loadModuleMapFile(SearchDirs[Idx].getDir(), IsSystem, /*IsFramework*/false) == LMM_NewlyLoaded) { // We just loaded a module map file; check whether the module is // available now. Module = ModMap.findModule(ModuleName); if (Module) break; } // Search for a module map in a subdirectory with the same name as the // module. SmallString<128> NestedModuleMapDirName; NestedModuleMapDirName = SearchDirs[Idx].getDir()->getName(); llvm::sys::path::append(NestedModuleMapDirName, ModuleName); if (loadModuleMapFile(NestedModuleMapDirName, IsSystem, /*IsFramework*/false) == LMM_NewlyLoaded){ // If we just loaded a module map file, look for the module again. Module = ModMap.findModule(ModuleName); if (Module) break; } // If we've already performed the exhaustive search for module maps in this // search directory, don't do it again. if (SearchDirs[Idx].haveSearchedAllModuleMaps()) continue; // Load all module maps in the immediate subdirectories of this search // directory. loadSubdirectoryModuleMaps(SearchDirs[Idx]); // Look again for the module. Module = ModMap.findModule(ModuleName); if (Module) break; } return Module; } //===----------------------------------------------------------------------===// // File lookup within a DirectoryLookup scope //===----------------------------------------------------------------------===// /// getName - Return the directory or filename corresponding to this lookup /// object. const char *DirectoryLookup::getName() const { if (isNormalDir()) return getDir()->getName(); if (isFramework()) return getFrameworkDir()->getName(); assert(isHeaderMap() && "Unknown DirectoryLookup"); return getHeaderMap()->getFileName(); } const FileEntry *HeaderSearch::getFileAndSuggestModule( StringRef FileName, SourceLocation IncludeLoc, const DirectoryEntry *Dir, bool IsSystemHeaderDir, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule) { // If we have a module map that might map this header, load it and // check whether we'll have a suggestion for a module. const FileEntry *File = getFileMgr().getFile(FileName, /*OpenFile=*/true); if (!File) return nullptr; // If there is a module that corresponds to this header, suggest it. if (!findUsableModuleForHeader(File, Dir ? Dir : File->getDir(), RequestingModule, SuggestedModule, IsSystemHeaderDir)) return nullptr; return File; } /// LookupFile - Lookup the specified file in this search path, returning it /// if it exists or returning null if not. const FileEntry *DirectoryLookup::LookupFile( StringRef &Filename, HeaderSearch &HS, SourceLocation IncludeLoc, SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule, bool &InUserSpecifiedSystemFramework, bool &HasBeenMapped, SmallVectorImpl<char> &MappedName) const { InUserSpecifiedSystemFramework = false; HasBeenMapped = false; SmallString<1024> TmpDir; if (isNormalDir()) { // Concatenate the requested file onto the directory. TmpDir = getDir()->getName(); llvm::sys::path::append(TmpDir, Filename); if (SearchPath) { StringRef SearchPathRef(getDir()->getName()); SearchPath->clear(); SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); } if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin(), Filename.end()); } return HS.getFileAndSuggestModule(TmpDir, IncludeLoc, getDir(), isSystemHeaderDirectory(), RequestingModule, SuggestedModule); } if (isFramework()) return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath, RequestingModule, SuggestedModule, InUserSpecifiedSystemFramework); assert(isHeaderMap() && "Unknown directory lookup"); const HeaderMap *HM = getHeaderMap(); SmallString<1024> Path; StringRef Dest = HM->lookupFilename(Filename, Path); if (Dest.empty()) return nullptr; const FileEntry *Result; // Check if the headermap maps the filename to a framework include // ("Foo.h" -> "Foo/Foo.h"), in which case continue header lookup using the // framework include. if (llvm::sys::path::is_relative(Dest)) { MappedName.clear(); MappedName.append(Dest.begin(), Dest.end()); Filename = StringRef(MappedName.begin(), MappedName.size()); HasBeenMapped = true; Result = HM->LookupFile(Filename, HS.getFileMgr()); } else { Result = HS.getFileMgr().getFile(Dest); } if (Result) { if (SearchPath) { StringRef SearchPathRef(getName()); SearchPath->clear(); SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); } if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin(), Filename.end()); } } return Result; } /// \brief Given a framework directory, find the top-most framework directory. /// /// \param FileMgr The file manager to use for directory lookups. /// \param DirName The name of the framework directory. /// \param SubmodulePath Will be populated with the submodule path from the /// returned top-level module to the originally named framework. static const DirectoryEntry * getTopFrameworkDir(FileManager &FileMgr, StringRef DirName, SmallVectorImpl<std::string> &SubmodulePath) { assert(llvm::sys::path::extension(DirName) == ".framework" && "Not a framework directory"); // Note: as an egregious but useful hack we use the real path here, because // frameworks moving between top-level frameworks to embedded frameworks tend // to be symlinked, and we base the logical structure of modules on the // physical layout. In particular, we need to deal with crazy includes like // // #include <Foo/Frameworks/Bar.framework/Headers/Wibble.h> // // where 'Bar' used to be embedded in 'Foo', is now a top-level framework // which one should access with, e.g., // // #include <Bar/Wibble.h> // // Similar issues occur when a top-level framework has moved into an // embedded framework. const DirectoryEntry *TopFrameworkDir = FileMgr.getDirectory(DirName); DirName = FileMgr.getCanonicalName(TopFrameworkDir); do { // Get the parent directory name. DirName = llvm::sys::path::parent_path(DirName); if (DirName.empty()) break; // Determine whether this directory exists. const DirectoryEntry *Dir = FileMgr.getDirectory(DirName); if (!Dir) break; // If this is a framework directory, then we're a subframework of this // framework. if (llvm::sys::path::extension(DirName) == ".framework") { SubmodulePath.push_back(llvm::sys::path::stem(DirName)); TopFrameworkDir = Dir; } } while (true); return TopFrameworkDir; } /// DoFrameworkLookup - Do a lookup of the specified file in the current /// DirectoryLookup, which is a framework directory. const FileEntry *DirectoryLookup::DoFrameworkLookup( StringRef Filename, HeaderSearch &HS, SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule, bool &InUserSpecifiedSystemFramework) const { FileManager &FileMgr = HS.getFileMgr(); // Framework names must have a '/' in the filename. size_t SlashPos = Filename.find('/'); if (SlashPos == StringRef::npos) return nullptr; // Find out if this is the home for the specified framework, by checking // HeaderSearch. Possible answers are yes/no and unknown. HeaderSearch::FrameworkCacheEntry &CacheEntry = HS.LookupFrameworkCache(Filename.substr(0, SlashPos)); // If it is known and in some other directory, fail. if (CacheEntry.Directory && CacheEntry.Directory != getFrameworkDir()) return nullptr; // Otherwise, construct the path to this framework dir. // FrameworkName = "/System/Library/Frameworks/" SmallString<1024> FrameworkName; FrameworkName += getFrameworkDir()->getName(); if (FrameworkName.empty() || FrameworkName.back() != '/') FrameworkName.push_back('/'); // FrameworkName = "/System/Library/Frameworks/Cocoa" StringRef ModuleName(Filename.begin(), SlashPos); FrameworkName += ModuleName; // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/" FrameworkName += ".framework/"; // If the cache entry was unresolved, populate it now. if (!CacheEntry.Directory) { HS.IncrementFrameworkLookupCount(); // If the framework dir doesn't exist, we fail. const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName); if (!Dir) return nullptr; // Otherwise, if it does, remember that this is the right direntry for this // framework. CacheEntry.Directory = getFrameworkDir(); // If this is a user search directory, check if the framework has been // user-specified as a system framework. if (getDirCharacteristic() == SrcMgr::C_User) { SmallString<1024> SystemFrameworkMarker(FrameworkName); SystemFrameworkMarker += ".system_framework"; if (llvm::sys::fs::exists(SystemFrameworkMarker)) { CacheEntry.IsUserSpecifiedSystemFramework = true; } } } // Set the 'user-specified system framework' flag. InUserSpecifiedSystemFramework = CacheEntry.IsUserSpecifiedSystemFramework; if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin()+SlashPos+1, Filename.end()); } // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h" unsigned OrigSize = FrameworkName.size(); FrameworkName += "Headers/"; if (SearchPath) { SearchPath->clear(); // Without trailing '/'. SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1); } FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end()); const FileEntry *FE = FileMgr.getFile(FrameworkName, /*openFile=*/!SuggestedModule); if (!FE) { // Check "/System/Library/Frameworks/Cocoa.framework/PrivateHeaders/file.h" const char *Private = "Private"; FrameworkName.insert(FrameworkName.begin()+OrigSize, Private, Private+strlen(Private)); if (SearchPath) SearchPath->insert(SearchPath->begin()+OrigSize, Private, Private+strlen(Private)); FE = FileMgr.getFile(FrameworkName, /*openFile=*/!SuggestedModule); } // If we found the header and are allowed to suggest a module, do so now. if (FE && SuggestedModule) { // Find the framework in which this header occurs. StringRef FrameworkPath = FE->getDir()->getName(); bool FoundFramework = false; do { // Determine whether this directory exists. const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkPath); if (!Dir) break; // If this is a framework directory, then we're a subframework of this // framework. if (llvm::sys::path::extension(FrameworkPath) == ".framework") { FoundFramework = true; break; } // Get the parent directory name. FrameworkPath = llvm::sys::path::parent_path(FrameworkPath); if (FrameworkPath.empty()) break; } while (true); bool IsSystem = getDirCharacteristic() != SrcMgr::C_User; if (FoundFramework) { if (!HS.findUsableModuleForFrameworkHeader( FE, FrameworkPath, RequestingModule, SuggestedModule, IsSystem)) return nullptr; } else { if (!HS.findUsableModuleForHeader(FE, getDir(), RequestingModule, SuggestedModule, IsSystem)) return nullptr; } } return FE; } void HeaderSearch::setTarget(const TargetInfo &Target) { ModMap.setTarget(Target); } //===----------------------------------------------------------------------===// // Header File Location. //===----------------------------------------------------------------------===// /// \brief Return true with a diagnostic if the file that MSVC would have found /// fails to match the one that Clang would have found with MSVC header search /// disabled. static bool checkMSVCHeaderSearch(DiagnosticsEngine &Diags, const FileEntry *MSFE, const FileEntry *FE, SourceLocation IncludeLoc) { if (MSFE && FE != MSFE) { Diags.Report(IncludeLoc, diag::ext_pp_include_search_ms) << MSFE->getName(); return true; } return false; } static const char *copyString(StringRef Str, llvm::BumpPtrAllocator &Alloc) { assert(!Str.empty()); char *CopyStr = Alloc.Allocate<char>(Str.size()+1); std::copy(Str.begin(), Str.end(), CopyStr); CopyStr[Str.size()] = '\0'; return CopyStr; } /// LookupFile - Given a "foo" or \<foo> reference, look up the indicated file, /// return null on failure. isAngled indicates whether the file reference is /// for system \#include's or not (i.e. using <> instead of ""). Includers, if /// non-empty, indicates where the \#including file(s) are, in case a relative /// search is needed. Microsoft mode will pass all \#including files. const FileEntry *HeaderSearch::LookupFile( StringRef Filename, SourceLocation IncludeLoc, bool isAngled, const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir, ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers, SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule, bool SkipCache, bool BuildSystemModule) { if (SuggestedModule) *SuggestedModule = ModuleMap::KnownHeader(); // If 'Filename' is absolute, check to see if it exists and no searching. if (llvm::sys::path::is_absolute(Filename)) { CurDir = nullptr; // If this was an #include_next "/absolute/file", fail. if (FromDir) return nullptr; if (SearchPath) SearchPath->clear(); if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin(), Filename.end()); } // Otherwise, just return the file. return getFileAndSuggestModule(Filename, IncludeLoc, nullptr, /*IsSystemHeaderDir*/false, RequestingModule, SuggestedModule); } // This is the header that MSVC's header search would have found. const FileEntry *MSFE = nullptr; ModuleMap::KnownHeader MSSuggestedModule; // Unless disabled, check to see if the file is in the #includer's // directory. This cannot be based on CurDir, because each includer could be // a #include of a subdirectory (#include "foo/bar.h") and a subsequent // include of "baz.h" should resolve to "whatever/foo/baz.h". // This search is not done for <> headers. if (!Includers.empty() && !isAngled && !NoCurDirSearch) { SmallString<1024> TmpDir; bool First = true; for (const auto &IncluderAndDir : Includers) { const FileEntry *Includer = IncluderAndDir.first; // Concatenate the requested file onto the directory. // FIXME: Portability. Filename concatenation should be in sys::Path. TmpDir = IncluderAndDir.second->getName(); TmpDir.push_back('/'); TmpDir.append(Filename.begin(), Filename.end()); // FIXME: We don't cache the result of getFileInfo across the call to // getFileAndSuggestModule, because it's a reference to an element of // a container that could be reallocated across this call. // // If we have no includer, that means we're processing a #include // from a module build. We should treat this as a system header if we're // building a [system] module. bool IncluderIsSystemHeader = Includer ? getFileInfo(Includer).DirInfo != SrcMgr::C_User : BuildSystemModule; if (const FileEntry *FE = getFileAndSuggestModule( TmpDir, IncludeLoc, IncluderAndDir.second, IncluderIsSystemHeader, RequestingModule, SuggestedModule)) { if (!Includer) { assert(First && "only first includer can have no file"); return FE; } // Leave CurDir unset. // This file is a system header or C++ unfriendly if the old file is. // // Note that we only use one of FromHFI/ToHFI at once, due to potential // reallocation of the underlying vector potentially making the first // reference binding dangling. HeaderFileInfo &FromHFI = getFileInfo(Includer); unsigned DirInfo = FromHFI.DirInfo; bool IndexHeaderMapHeader = FromHFI.IndexHeaderMapHeader; StringRef Framework = FromHFI.Framework; HeaderFileInfo &ToHFI = getFileInfo(FE); ToHFI.DirInfo = DirInfo; ToHFI.IndexHeaderMapHeader = IndexHeaderMapHeader; ToHFI.Framework = Framework; if (SearchPath) { StringRef SearchPathRef(IncluderAndDir.second->getName()); SearchPath->clear(); SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); } if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin(), Filename.end()); } if (First) return FE; // Otherwise, we found the path via MSVC header search rules. If // -Wmsvc-include is enabled, we have to keep searching to see if we // would've found this header in -I or -isystem directories. if (Diags.isIgnored(diag::ext_pp_include_search_ms, IncludeLoc)) { return FE; } else { MSFE = FE; if (SuggestedModule) { MSSuggestedModule = *SuggestedModule; *SuggestedModule = ModuleMap::KnownHeader(); } break; } } First = false; } } CurDir = nullptr; // If this is a system #include, ignore the user #include locs. unsigned i = isAngled ? AngledDirIdx : 0; // If this is a #include_next request, start searching after the directory the // file was found in. if (FromDir) i = FromDir-&SearchDirs[0]; // Cache all of the lookups performed by this method. Many headers are // multiply included, and the "pragma once" optimization prevents them from // being relex/pp'd, but they would still have to search through a // (potentially huge) series of SearchDirs to find it. LookupFileCacheInfo &CacheLookup = LookupFileCache[Filename]; // If the entry has been previously looked up, the first value will be // non-zero. If the value is equal to i (the start point of our search), then // this is a matching hit. if (!SkipCache && CacheLookup.StartIdx == i+1) { // Skip querying potentially lots of directories for this lookup. i = CacheLookup.HitIdx; if (CacheLookup.MappedName) Filename = CacheLookup.MappedName; } else { // Otherwise, this is the first query, or the previous query didn't match // our search start. We will fill in our found location below, so prime the // start point value. CacheLookup.reset(/*StartIdx=*/i+1); } SmallString<64> MappedName; // Check each directory in sequence to see if it contains this file. for (; i != SearchDirs.size(); ++i) { bool InUserSpecifiedSystemFramework = false; bool HasBeenMapped = false; const FileEntry *FE = SearchDirs[i].LookupFile( Filename, *this, IncludeLoc, SearchPath, RelativePath, RequestingModule, SuggestedModule, InUserSpecifiedSystemFramework, HasBeenMapped, MappedName); if (HasBeenMapped) { CacheLookup.MappedName = copyString(Filename, LookupFileCache.getAllocator()); } if (!FE) continue; CurDir = &SearchDirs[i]; // This file is a system header or C++ unfriendly if the dir is. HeaderFileInfo &HFI = getFileInfo(FE); HFI.DirInfo = CurDir->getDirCharacteristic(); // If the directory characteristic is User but this framework was // user-specified to be treated as a system framework, promote the // characteristic. if (HFI.DirInfo == SrcMgr::C_User && InUserSpecifiedSystemFramework) HFI.DirInfo = SrcMgr::C_System; // If the filename matches a known system header prefix, override // whether the file is a system header. for (unsigned j = SystemHeaderPrefixes.size(); j; --j) { if (Filename.startswith(SystemHeaderPrefixes[j-1].first)) { HFI.DirInfo = SystemHeaderPrefixes[j-1].second ? SrcMgr::C_System : SrcMgr::C_User; break; } } // If this file is found in a header map and uses the framework style of // includes, then this header is part of a framework we're building. if (CurDir->isIndexHeaderMap()) { size_t SlashPos = Filename.find('/'); if (SlashPos != StringRef::npos) { HFI.IndexHeaderMapHeader = 1; HFI.Framework = getUniqueFrameworkName(StringRef(Filename.begin(), SlashPos)); } } if (checkMSVCHeaderSearch(Diags, MSFE, FE, IncludeLoc)) { if (SuggestedModule) *SuggestedModule = MSSuggestedModule; return MSFE; } // Remember this location for the next lookup we do. CacheLookup.HitIdx = i; return FE; } // If we are including a file with a quoted include "foo.h" from inside // a header in a framework that is currently being built, and we couldn't // resolve "foo.h" any other way, change the include to <Foo/foo.h>, where // "Foo" is the name of the framework in which the including header was found. if (!Includers.empty() && Includers.front().first && !isAngled && Filename.find('/') == StringRef::npos) { HeaderFileInfo &IncludingHFI = getFileInfo(Includers.front().first); if (IncludingHFI.IndexHeaderMapHeader) { SmallString<128> ScratchFilename; ScratchFilename += IncludingHFI.Framework; ScratchFilename += '/'; ScratchFilename += Filename; const FileEntry *FE = LookupFile(ScratchFilename, IncludeLoc, /*isAngled=*/true, FromDir, CurDir, Includers.front(), SearchPath, RelativePath, RequestingModule, SuggestedModule); if (checkMSVCHeaderSearch(Diags, MSFE, FE, IncludeLoc)) { if (SuggestedModule) *SuggestedModule = MSSuggestedModule; return MSFE; } LookupFileCacheInfo &CacheLookup = LookupFileCache[Filename]; CacheLookup.HitIdx = LookupFileCache[ScratchFilename].HitIdx; // FIXME: SuggestedModule. return FE; } } if (checkMSVCHeaderSearch(Diags, MSFE, nullptr, IncludeLoc)) { if (SuggestedModule) *SuggestedModule = MSSuggestedModule; return MSFE; } // Otherwise, didn't find it. Remember we didn't find this. CacheLookup.HitIdx = SearchDirs.size(); return nullptr; } /// LookupSubframeworkHeader - Look up a subframework for the specified /// \#include file. For example, if \#include'ing <HIToolbox/HIToolbox.h> from /// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox /// is a subframework within Carbon.framework. If so, return the FileEntry /// for the designated file, otherwise return null. const FileEntry *HeaderSearch:: LookupSubframeworkHeader(StringRef Filename, const FileEntry *ContextFileEnt, SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule) { assert(ContextFileEnt && "No context file?"); // Framework names must have a '/' in the filename. Find it. // FIXME: Should we permit '\' on Windows? size_t SlashPos = Filename.find('/'); if (SlashPos == StringRef::npos) return nullptr; // Look up the base framework name of the ContextFileEnt. const char *ContextName = ContextFileEnt->getName(); // If the context info wasn't a framework, couldn't be a subframework. const unsigned DotFrameworkLen = 10; const char *FrameworkPos = strstr(ContextName, ".framework"); if (FrameworkPos == nullptr || (FrameworkPos[DotFrameworkLen] != '/' && FrameworkPos[DotFrameworkLen] != '\\')) return nullptr; SmallString<1024> FrameworkName(ContextName, FrameworkPos+DotFrameworkLen+1); // Append Frameworks/HIToolbox.framework/ FrameworkName += "Frameworks/"; FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos); FrameworkName += ".framework/"; auto &CacheLookup = *FrameworkMap.insert(std::make_pair(Filename.substr(0, SlashPos), FrameworkCacheEntry())).first; // Some other location? if (CacheLookup.second.Directory && CacheLookup.first().size() == FrameworkName.size() && memcmp(CacheLookup.first().data(), &FrameworkName[0], CacheLookup.first().size()) != 0) return nullptr; // Cache subframework. if (!CacheLookup.second.Directory) { ++NumSubFrameworkLookups; // If the framework dir doesn't exist, we fail. const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName); if (!Dir) return nullptr; // Otherwise, if it does, remember that this is the right direntry for this // framework. CacheLookup.second.Directory = Dir; } const FileEntry *FE = nullptr; if (RelativePath) { RelativePath->clear(); RelativePath->append(Filename.begin()+SlashPos+1, Filename.end()); } // Check ".../Frameworks/HIToolbox.framework/Headers/HIToolbox.h" SmallString<1024> HeadersFilename(FrameworkName); HeadersFilename += "Headers/"; if (SearchPath) { SearchPath->clear(); // Without trailing '/'. SearchPath->append(HeadersFilename.begin(), HeadersFilename.end()-1); } HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end()); if (!(FE = FileMgr.getFile(HeadersFilename, /*openFile=*/true))) { // Check ".../Frameworks/HIToolbox.framework/PrivateHeaders/HIToolbox.h" HeadersFilename = FrameworkName; HeadersFilename += "PrivateHeaders/"; if (SearchPath) { SearchPath->clear(); // Without trailing '/'. SearchPath->append(HeadersFilename.begin(), HeadersFilename.end()-1); } HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end()); if (!(FE = FileMgr.getFile(HeadersFilename, /*openFile=*/true))) return nullptr; } // This file is a system header or C++ unfriendly if the old file is. // // Note that the temporary 'DirInfo' is required here, as either call to // getFileInfo could resize the vector and we don't want to rely on order // of evaluation. unsigned DirInfo = getFileInfo(ContextFileEnt).DirInfo; getFileInfo(FE).DirInfo = DirInfo; FrameworkName.pop_back(); // remove the trailing '/' if (!findUsableModuleForFrameworkHeader(FE, FrameworkName, RequestingModule, SuggestedModule, /*IsSystem*/ false)) return nullptr; return FE; } //===----------------------------------------------------------------------===// // File Info Management. //===----------------------------------------------------------------------===// /// \brief Merge the header file info provided by \p OtherHFI into the current /// header file info (\p HFI) static void mergeHeaderFileInfo(HeaderFileInfo &HFI, const HeaderFileInfo &OtherHFI) { assert(OtherHFI.External && "expected to merge external HFI"); HFI.isImport |= OtherHFI.isImport; HFI.isPragmaOnce |= OtherHFI.isPragmaOnce; HFI.isModuleHeader |= OtherHFI.isModuleHeader; HFI.NumIncludes += OtherHFI.NumIncludes; if (!HFI.ControllingMacro && !HFI.ControllingMacroID) { HFI.ControllingMacro = OtherHFI.ControllingMacro; HFI.ControllingMacroID = OtherHFI.ControllingMacroID; } HFI.DirInfo = OtherHFI.DirInfo; HFI.External = (!HFI.IsValid || HFI.External); HFI.IsValid = true; HFI.IndexHeaderMapHeader = OtherHFI.IndexHeaderMapHeader; if (HFI.Framework.empty()) HFI.Framework = OtherHFI.Framework; } /// getFileInfo - Return the HeaderFileInfo structure for the specified /// FileEntry. HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) { if (FE->getUID() >= FileInfo.size()) FileInfo.resize(FE->getUID() + 1); HeaderFileInfo *HFI = &FileInfo[FE->getUID()]; // FIXME: Use a generation count to check whether this is really up to date. if (ExternalSource && !HFI->Resolved) { HFI->Resolved = true; auto ExternalHFI = ExternalSource->GetHeaderFileInfo(FE); HFI = &FileInfo[FE->getUID()]; if (ExternalHFI.External) mergeHeaderFileInfo(*HFI, ExternalHFI); } HFI->IsValid = true; // We have local information about this header file, so it's no longer // strictly external. HFI->External = false; return *HFI; } const HeaderFileInfo * HeaderSearch::getExistingFileInfo(const FileEntry *FE, bool WantExternal) const { // If we have an external source, ensure we have the latest information. // FIXME: Use a generation count to check whether this is really up to date. HeaderFileInfo *HFI; if (ExternalSource) { if (FE->getUID() >= FileInfo.size()) { if (!WantExternal) return nullptr; FileInfo.resize(FE->getUID() + 1); } HFI = &FileInfo[FE->getUID()]; if (!WantExternal && (!HFI->IsValid || HFI->External)) return nullptr; if (!HFI->Resolved) { HFI->Resolved = true; auto ExternalHFI = ExternalSource->GetHeaderFileInfo(FE); HFI = &FileInfo[FE->getUID()]; if (ExternalHFI.External) mergeHeaderFileInfo(*HFI, ExternalHFI); } } else if (FE->getUID() >= FileInfo.size()) { return nullptr; } else { HFI = &FileInfo[FE->getUID()]; } if (!HFI->IsValid || (HFI->External && !WantExternal)) return nullptr; return HFI; } bool HeaderSearch::isFileMultipleIncludeGuarded(const FileEntry *File) { // Check if we've ever seen this file as a header. if (auto *HFI = getExistingFileInfo(File)) return HFI->isPragmaOnce || HFI->isImport || HFI->ControllingMacro || HFI->ControllingMacroID; return false; } void HeaderSearch::MarkFileModuleHeader(const FileEntry *FE, ModuleMap::ModuleHeaderRole Role, bool isCompilingModuleHeader) { bool isModularHeader = !(Role & ModuleMap::TextualHeader); // Don't mark the file info as non-external if there's nothing to change. if (!isCompilingModuleHeader) { if (!isModularHeader) return; auto *HFI = getExistingFileInfo(FE); if (HFI && HFI->isModuleHeader) return; } auto &HFI = getFileInfo(FE); HFI.isModuleHeader |= isModularHeader; HFI.isCompilingModuleHeader |= isCompilingModuleHeader; } bool HeaderSearch::ShouldEnterIncludeFile(Preprocessor &PP, const FileEntry *File, bool isImport, Module *M) { ++NumIncluded; // Count # of attempted #includes. // Get information about this file. HeaderFileInfo &FileInfo = getFileInfo(File); // If this is a #import directive, check that we have not already imported // this header. if (isImport) { // If this has already been imported, don't import it again. FileInfo.isImport = true; // Has this already been #import'ed or #include'd? if (FileInfo.NumIncludes) return false; } else { // Otherwise, if this is a #include of a file that was previously #import'd // or if this is the second #include of a #pragma once file, ignore it. if (FileInfo.isImport) return false; } // Next, check to see if the file is wrapped with #ifndef guards. If so, and // if the macro that guards it is defined, we know the #include has no effect. if (const IdentifierInfo *ControllingMacro = FileInfo.getControllingMacro(ExternalLookup)) { // If the header corresponds to a module, check whether the macro is already // defined in that module rather than checking in the current set of visible // modules. if (M ? PP.isMacroDefinedInLocalModule(ControllingMacro, M) : PP.isMacroDefined(ControllingMacro)) { ++NumMultiIncludeFileOptzn; return false; } } // Increment the number of times this file has been included. ++FileInfo.NumIncludes; return true; } size_t HeaderSearch::getTotalMemory() const { return SearchDirs.capacity() + llvm::capacity_in_bytes(FileInfo) + llvm::capacity_in_bytes(HeaderMaps) + LookupFileCache.getAllocator().getTotalMemory() + FrameworkMap.getAllocator().getTotalMemory(); } StringRef HeaderSearch::getUniqueFrameworkName(StringRef Framework) { return FrameworkNames.insert(Framework).first->first(); } bool HeaderSearch::hasModuleMap(StringRef FileName, const DirectoryEntry *Root, bool IsSystem) { if (!HSOpts->ImplicitModuleMaps) return false; SmallVector<const DirectoryEntry *, 2> FixUpDirectories; StringRef DirName = FileName; do { // Get the parent directory name. DirName = llvm::sys::path::parent_path(DirName); if (DirName.empty()) return false; // Determine whether this directory exists. const DirectoryEntry *Dir = FileMgr.getDirectory(DirName); if (!Dir) return false; // Try to load the module map file in this directory. switch (loadModuleMapFile(Dir, IsSystem, llvm::sys::path::extension(Dir->getName()) == ".framework")) { case LMM_NewlyLoaded: case LMM_AlreadyLoaded: // Success. All of the directories we stepped through inherit this module // map file. for (unsigned I = 0, N = FixUpDirectories.size(); I != N; ++I) DirectoryHasModuleMap[FixUpDirectories[I]] = true; return true; case LMM_NoDirectory: case LMM_InvalidModuleMap: break; } // If we hit the top of our search, we're done. if (Dir == Root) return false; // Keep track of all of the directories we checked, so we can mark them as // having module maps if we eventually do find a module map. FixUpDirectories.push_back(Dir); } while (true); } ModuleMap::KnownHeader HeaderSearch::findModuleForHeader(const FileEntry *File) const { if (ExternalSource) { // Make sure the external source has handled header info about this file, // which includes whether the file is part of a module. (void)getExistingFileInfo(File); } return ModMap.findModuleForHeader(File); } bool HeaderSearch::findUsableModuleForHeader( const FileEntry *File, const DirectoryEntry *Root, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule, bool IsSystemHeaderDir) { if (File && SuggestedModule) { // If there is a module that corresponds to this header, suggest it. hasModuleMap(File->getName(), Root, IsSystemHeaderDir); *SuggestedModule = findModuleForHeader(File); } return true; } bool HeaderSearch::findUsableModuleForFrameworkHeader( const FileEntry *File, StringRef FrameworkName, Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule, bool IsSystemFramework) { // If we're supposed to suggest a module, look for one now. if (SuggestedModule) { // Find the top-level framework based on this framework. SmallVector<std::string, 4> SubmodulePath; const DirectoryEntry *TopFrameworkDir = ::getTopFrameworkDir(FileMgr, FrameworkName, SubmodulePath); // Determine the name of the top-level framework. StringRef ModuleName = llvm::sys::path::stem(TopFrameworkDir->getName()); // Load this framework module. If that succeeds, find the suggested module // for this header, if any. loadFrameworkModule(ModuleName, TopFrameworkDir, IsSystemFramework); // FIXME: This can find a module not part of ModuleName, which is // important so that we're consistent about whether this header // corresponds to a module. Possibly we should lock down framework modules // so that this is not possible. *SuggestedModule = findModuleForHeader(File); } return true; } static const FileEntry *getPrivateModuleMap(const FileEntry *File, FileManager &FileMgr) { StringRef Filename = llvm::sys::path::filename(File->getName()); SmallString<128> PrivateFilename(File->getDir()->getName()); if (Filename == "module.map") llvm::sys::path::append(PrivateFilename, "module_private.map"); else if (Filename == "module.modulemap") llvm::sys::path::append(PrivateFilename, "module.private.modulemap"); else return nullptr; return FileMgr.getFile(PrivateFilename); } bool HeaderSearch::loadModuleMapFile(const FileEntry *File, bool IsSystem) { // Find the directory for the module. For frameworks, that may require going // up from the 'Modules' directory. const DirectoryEntry *Dir = nullptr; if (getHeaderSearchOpts().ModuleMapFileHomeIsCwd) Dir = FileMgr.getDirectory("."); else { Dir = File->getDir(); StringRef DirName(Dir->getName()); if (llvm::sys::path::filename(DirName) == "Modules") { DirName = llvm::sys::path::parent_path(DirName); if (DirName.endswith(".framework")) Dir = FileMgr.getDirectory(DirName); // FIXME: This assert can fail if there's a race between the above check // and the removal of the directory. assert(Dir && "parent must exist"); } } switch (loadModuleMapFileImpl(File, IsSystem, Dir)) { case LMM_AlreadyLoaded: case LMM_NewlyLoaded: return false; case LMM_NoDirectory: case LMM_InvalidModuleMap: return true; } llvm_unreachable("Unknown load module map result"); } HeaderSearch::LoadModuleMapResult HeaderSearch::loadModuleMapFileImpl(const FileEntry *File, bool IsSystem, const DirectoryEntry *Dir) { assert(File && "expected FileEntry"); // Check whether we've already loaded this module map, and mark it as being // loaded in case we recursively try to load it from itself. auto AddResult = LoadedModuleMaps.insert(std::make_pair(File, true)); if (!AddResult.second) return AddResult.first->second ? LMM_AlreadyLoaded : LMM_InvalidModuleMap; if (ModMap.parseModuleMapFile(File, IsSystem, Dir)) { LoadedModuleMaps[File] = false; return LMM_InvalidModuleMap; } // Try to load a corresponding private module map. if (const FileEntry *PMMFile = getPrivateModuleMap(File, FileMgr)) { if (ModMap.parseModuleMapFile(PMMFile, IsSystem, Dir)) { LoadedModuleMaps[File] = false; return LMM_InvalidModuleMap; } } // This directory has a module map. return LMM_NewlyLoaded; } const FileEntry * HeaderSearch::lookupModuleMapFile(const DirectoryEntry *Dir, bool IsFramework) { if (!HSOpts->ImplicitModuleMaps) return nullptr; // For frameworks, the preferred spelling is Modules/module.modulemap, but // module.map at the framework root is also accepted. SmallString<128> ModuleMapFileName(Dir->getName()); if (IsFramework) llvm::sys::path::append(ModuleMapFileName, "Modules"); llvm::sys::path::append(ModuleMapFileName, "module.modulemap"); if (const FileEntry *F = FileMgr.getFile(ModuleMapFileName)) return F; // Continue to allow module.map ModuleMapFileName = Dir->getName(); llvm::sys::path::append(ModuleMapFileName, "module.map"); return FileMgr.getFile(ModuleMapFileName); } Module *HeaderSearch::loadFrameworkModule(StringRef Name, const DirectoryEntry *Dir, bool IsSystem) { if (Module *Module = ModMap.findModule(Name)) return Module; // Try to load a module map file. switch (loadModuleMapFile(Dir, IsSystem, /*IsFramework*/true)) { case LMM_InvalidModuleMap: // Try to infer a module map from the framework directory. if (HSOpts->ImplicitModuleMaps) ModMap.inferFrameworkModule(Dir, IsSystem, /*Parent=*/nullptr); break; case LMM_AlreadyLoaded: case LMM_NoDirectory: return nullptr; case LMM_NewlyLoaded: break; } return ModMap.findModule(Name); } HeaderSearch::LoadModuleMapResult HeaderSearch::loadModuleMapFile(StringRef DirName, bool IsSystem, bool IsFramework) { if (const DirectoryEntry *Dir = FileMgr.getDirectory(DirName)) return loadModuleMapFile(Dir, IsSystem, IsFramework); return LMM_NoDirectory; } HeaderSearch::LoadModuleMapResult HeaderSearch::loadModuleMapFile(const DirectoryEntry *Dir, bool IsSystem, bool IsFramework) { auto KnownDir = DirectoryHasModuleMap.find(Dir); if (KnownDir != DirectoryHasModuleMap.end()) return KnownDir->second ? LMM_AlreadyLoaded : LMM_InvalidModuleMap; if (const FileEntry *ModuleMapFile = lookupModuleMapFile(Dir, IsFramework)) { LoadModuleMapResult Result = loadModuleMapFileImpl(ModuleMapFile, IsSystem, Dir); // Add Dir explicitly in case ModuleMapFile is in a subdirectory. // E.g. Foo.framework/Modules/module.modulemap // ^Dir ^ModuleMapFile if (Result == LMM_NewlyLoaded) DirectoryHasModuleMap[Dir] = true; else if (Result == LMM_InvalidModuleMap) DirectoryHasModuleMap[Dir] = false; return Result; } return LMM_InvalidModuleMap; } void HeaderSearch::collectAllModules(SmallVectorImpl<Module *> &Modules) { Modules.clear(); if (HSOpts->ImplicitModuleMaps) { // Load module maps for each of the header search directories. for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) { bool IsSystem = SearchDirs[Idx].isSystemHeaderDirectory(); if (SearchDirs[Idx].isFramework()) { std::error_code EC; SmallString<128> DirNative; llvm::sys::path::native(SearchDirs[Idx].getFrameworkDir()->getName(), DirNative); // Search each of the ".framework" directories to load them as modules. vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem(); for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd; Dir != DirEnd && !EC; Dir.increment(EC)) { if (llvm::sys::path::extension(Dir->getName()) != ".framework") continue; const DirectoryEntry *FrameworkDir = FileMgr.getDirectory(Dir->getName()); if (!FrameworkDir) continue; // Load this framework module. loadFrameworkModule(llvm::sys::path::stem(Dir->getName()), FrameworkDir, IsSystem); } continue; } // FIXME: Deal with header maps. if (SearchDirs[Idx].isHeaderMap()) continue; // Try to load a module map file for the search directory. loadModuleMapFile(SearchDirs[Idx].getDir(), IsSystem, /*IsFramework*/ false); // Try to load module map files for immediate subdirectories of this // search directory. loadSubdirectoryModuleMaps(SearchDirs[Idx]); } } // Populate the list of modules. for (ModuleMap::module_iterator M = ModMap.module_begin(), MEnd = ModMap.module_end(); M != MEnd; ++M) { Modules.push_back(M->getValue()); } } void HeaderSearch::loadTopLevelSystemModules() { if (!HSOpts->ImplicitModuleMaps) return; // Load module maps for each of the header search directories. for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) { // We only care about normal header directories. if (!SearchDirs[Idx].isNormalDir()) { continue; } // Try to load a module map file for the search directory. loadModuleMapFile(SearchDirs[Idx].getDir(), SearchDirs[Idx].isSystemHeaderDirectory(), SearchDirs[Idx].isFramework()); } } void HeaderSearch::loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir) { assert(HSOpts->ImplicitModuleMaps && "Should not be loading subdirectory module maps"); if (SearchDir.haveSearchedAllModuleMaps()) return; std::error_code EC; SmallString<128> DirNative; llvm::sys::path::native(SearchDir.getDir()->getName(), DirNative); vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem(); for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd; Dir != DirEnd && !EC; Dir.increment(EC)) { bool IsFramework = llvm::sys::path::extension(Dir->getName()) == ".framework"; if (IsFramework == SearchDir.isFramework()) loadModuleMapFile(Dir->getName(), SearchDir.isSystemHeaderDirectory(), SearchDir.isFramework()); } SearchDir.setSearchedAllModuleMaps(true); } std::string HeaderSearch::suggestPathToFileForDiagnostics(const FileEntry *File, bool *IsSystem) { // FIXME: We assume that the path name currently cached in the FileEntry is // the most appropriate one for this analysis (and that it's spelled the same // way as the corresponding header search path). const char *Name = File->getName(); unsigned BestPrefixLength = 0; unsigned BestSearchDir; for (unsigned I = 0; I != SearchDirs.size(); ++I) { // FIXME: Support this search within frameworks and header maps. if (!SearchDirs[I].isNormalDir()) continue; const char *Dir = SearchDirs[I].getDir()->getName(); for (auto NI = llvm::sys::path::begin(Name), NE = llvm::sys::path::end(Name), DI = llvm::sys::path::begin(Dir), DE = llvm::sys::path::end(Dir); /*termination condition in loop*/; ++NI, ++DI) { // '.' components in Name are ignored. while (NI != NE && *NI == ".") ++NI; if (NI == NE) break; // '.' components in Dir are ignored. while (DI != DE && *DI == ".") ++DI; if (DI == DE) { // Dir is a prefix of Name, up to '.' components and choice of path // separators. unsigned PrefixLength = NI - llvm::sys::path::begin(Name); if (PrefixLength > BestPrefixLength) { BestPrefixLength = PrefixLength; BestSearchDir = I; } break; } if (*NI != *DI) break; } } if (IsSystem) *IsSystem = BestPrefixLength ? BestSearchDir >= SystemDirIdx : false; return Name + BestPrefixLength; }