1 //===- VirtualFileSystem.cpp - Virtual File System Layer --------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
9 // This file implements the VirtualFileSystem interface.
10 //===----------------------------------------------------------------------===//
12 #include "clang/Basic/VirtualFileSystem.h"
13 #include "clang/Basic/FileManager.h"
14 #include "llvm/ADT/DenseMap.h"
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/ADT/StringSet.h"
18 #include "llvm/ADT/iterator_range.h"
19 #include "llvm/Config/llvm-config.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/Errc.h"
22 #include "llvm/Support/MemoryBuffer.h"
23 #include "llvm/Support/Path.h"
24 #include "llvm/Support/Process.h"
25 #include "llvm/Support/YAMLParser.h"
37 using namespace clang;
38 using namespace clang::vfs;
40 using llvm::sys::fs::file_status;
41 using llvm::sys::fs::file_type;
42 using llvm::sys::fs::perms;
43 using llvm::sys::fs::UniqueID;
45 Status::Status(const file_status &Status)
46 : UID(Status.getUniqueID()), MTime(Status.getLastModificationTime()),
47 User(Status.getUser()), Group(Status.getGroup()), Size(Status.getSize()),
48 Type(Status.type()), Perms(Status.permissions()), IsVFSMapped(false) {}
50 Status::Status(StringRef Name, UniqueID UID, sys::TimePoint<> MTime,
51 uint32_t User, uint32_t Group, uint64_t Size, file_type Type,
53 : Name(Name), UID(UID), MTime(MTime), User(User), Group(Group), Size(Size),
54 Type(Type), Perms(Perms), IsVFSMapped(false) {}
56 Status Status::copyWithNewName(const Status &In, StringRef NewName) {
57 return Status(NewName, In.getUniqueID(), In.getLastModificationTime(),
58 In.getUser(), In.getGroup(), In.getSize(), In.getType(),
62 Status Status::copyWithNewName(const file_status &In, StringRef NewName) {
63 return Status(NewName, In.getUniqueID(), In.getLastModificationTime(),
64 In.getUser(), In.getGroup(), In.getSize(), In.type(),
68 bool Status::equivalent(const Status &Other) const {
69 return getUniqueID() == Other.getUniqueID();
71 bool Status::isDirectory() const {
72 return Type == file_type::directory_file;
74 bool Status::isRegularFile() const {
75 return Type == file_type::regular_file;
77 bool Status::isOther() const {
78 return exists() && !isRegularFile() && !isDirectory() && !isSymlink();
80 bool Status::isSymlink() const {
81 return Type == file_type::symlink_file;
83 bool Status::isStatusKnown() const {
84 return Type != file_type::status_error;
86 bool Status::exists() const {
87 return isStatusKnown() && Type != file_type::file_not_found;
92 FileSystem::~FileSystem() {}
94 ErrorOr<std::unique_ptr<MemoryBuffer>>
95 FileSystem::getBufferForFile(const llvm::Twine &Name, int64_t FileSize,
96 bool RequiresNullTerminator, bool IsVolatile) {
97 auto F = openFileForRead(Name);
101 return (*F)->getBuffer(Name, FileSize, RequiresNullTerminator, IsVolatile);
104 std::error_code FileSystem::makeAbsolute(SmallVectorImpl<char> &Path) const {
105 if (llvm::sys::path::is_absolute(Path))
106 return std::error_code();
108 auto WorkingDir = getCurrentWorkingDirectory();
110 return WorkingDir.getError();
112 return llvm::sys::fs::make_absolute(WorkingDir.get(), Path);
115 bool FileSystem::exists(const Twine &Path) {
116 auto Status = status(Path);
117 return Status && Status->exists();
121 static bool isTraversalComponent(StringRef Component) {
122 return Component.equals("..") || Component.equals(".");
125 static bool pathHasTraversal(StringRef Path) {
126 using namespace llvm::sys;
127 for (StringRef Comp : llvm::make_range(path::begin(Path), path::end(Path)))
128 if (isTraversalComponent(Comp))
134 //===-----------------------------------------------------------------------===/
135 // RealFileSystem implementation
136 //===-----------------------------------------------------------------------===/
139 /// \brief Wrapper around a raw file descriptor.
140 class RealFile : public File {
143 std::string RealName;
144 friend class RealFileSystem;
145 RealFile(int FD, StringRef NewName, StringRef NewRealPathName)
146 : FD(FD), S(NewName, {}, {}, {}, {}, {},
147 llvm::sys::fs::file_type::status_error, {}),
148 RealName(NewRealPathName.str()) {
149 assert(FD >= 0 && "Invalid or inactive file descriptor");
153 ~RealFile() override;
154 ErrorOr<Status> status() override;
155 ErrorOr<std::string> getName() override;
156 ErrorOr<std::unique_ptr<MemoryBuffer>> getBuffer(const Twine &Name,
158 bool RequiresNullTerminator,
159 bool IsVolatile) override;
160 std::error_code close() override;
162 } // end anonymous namespace
163 RealFile::~RealFile() { close(); }
165 ErrorOr<Status> RealFile::status() {
166 assert(FD != -1 && "cannot stat closed file");
167 if (!S.isStatusKnown()) {
168 file_status RealStatus;
169 if (std::error_code EC = sys::fs::status(FD, RealStatus))
171 S = Status::copyWithNewName(RealStatus, S.getName());
176 ErrorOr<std::string> RealFile::getName() {
177 return RealName.empty() ? S.getName().str() : RealName;
180 ErrorOr<std::unique_ptr<MemoryBuffer>>
181 RealFile::getBuffer(const Twine &Name, int64_t FileSize,
182 bool RequiresNullTerminator, bool IsVolatile) {
183 assert(FD != -1 && "cannot get buffer for closed file");
184 return MemoryBuffer::getOpenFile(FD, Name, FileSize, RequiresNullTerminator,
188 std::error_code RealFile::close() {
189 std::error_code EC = sys::Process::SafelyCloseFileDescriptor(FD);
195 /// \brief The file system according to your operating system.
196 class RealFileSystem : public FileSystem {
198 ErrorOr<Status> status(const Twine &Path) override;
199 ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
200 directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
202 llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override;
203 std::error_code setCurrentWorkingDirectory(const Twine &Path) override;
205 } // end anonymous namespace
207 ErrorOr<Status> RealFileSystem::status(const Twine &Path) {
208 sys::fs::file_status RealStatus;
209 if (std::error_code EC = sys::fs::status(Path, RealStatus))
211 return Status::copyWithNewName(RealStatus, Path.str());
214 ErrorOr<std::unique_ptr<File>>
215 RealFileSystem::openFileForRead(const Twine &Name) {
217 SmallString<256> RealName;
218 if (std::error_code EC = sys::fs::openFileForRead(Name, FD, &RealName))
220 return std::unique_ptr<File>(new RealFile(FD, Name.str(), RealName.str()));
223 llvm::ErrorOr<std::string> RealFileSystem::getCurrentWorkingDirectory() const {
224 SmallString<256> Dir;
225 if (std::error_code EC = llvm::sys::fs::current_path(Dir))
227 return Dir.str().str();
230 std::error_code RealFileSystem::setCurrentWorkingDirectory(const Twine &Path) {
231 // FIXME: chdir is thread hostile; on the other hand, creating the same
232 // behavior as chdir is complex: chdir resolves the path once, thus
233 // guaranteeing that all subsequent relative path operations work
234 // on the same path the original chdir resulted in. This makes a
235 // difference for example on network filesystems, where symlinks might be
236 // switched during runtime of the tool. Fixing this depends on having a
237 // file system abstraction that allows openat() style interactions.
238 SmallString<256> Storage;
239 StringRef Dir = Path.toNullTerminatedStringRef(Storage);
240 if (int Err = ::chdir(Dir.data()))
241 return std::error_code(Err, std::generic_category());
242 return std::error_code();
245 IntrusiveRefCntPtr<FileSystem> vfs::getRealFileSystem() {
246 static IntrusiveRefCntPtr<FileSystem> FS = new RealFileSystem();
251 class RealFSDirIter : public clang::vfs::detail::DirIterImpl {
253 llvm::sys::fs::directory_iterator Iter;
255 RealFSDirIter(const Twine &_Path, std::error_code &EC)
256 : Path(_Path.str()), Iter(Path, EC) {
257 if (!EC && Iter != llvm::sys::fs::directory_iterator()) {
258 llvm::sys::fs::file_status S;
259 EC = Iter->status(S);
261 CurrentEntry = Status::copyWithNewName(S, Iter->path());
265 std::error_code increment() override {
270 } else if (Iter == llvm::sys::fs::directory_iterator()) {
271 CurrentEntry = Status();
273 llvm::sys::fs::file_status S;
274 EC = Iter->status(S);
275 CurrentEntry = Status::copyWithNewName(S, Iter->path());
282 directory_iterator RealFileSystem::dir_begin(const Twine &Dir,
283 std::error_code &EC) {
284 return directory_iterator(std::make_shared<RealFSDirIter>(Dir, EC));
287 //===-----------------------------------------------------------------------===/
288 // OverlayFileSystem implementation
289 //===-----------------------------------------------------------------------===/
290 OverlayFileSystem::OverlayFileSystem(IntrusiveRefCntPtr<FileSystem> BaseFS) {
291 FSList.push_back(std::move(BaseFS));
294 void OverlayFileSystem::pushOverlay(IntrusiveRefCntPtr<FileSystem> FS) {
295 FSList.push_back(FS);
296 // Synchronize added file systems by duplicating the working directory from
297 // the first one in the list.
298 FS->setCurrentWorkingDirectory(getCurrentWorkingDirectory().get());
301 ErrorOr<Status> OverlayFileSystem::status(const Twine &Path) {
302 // FIXME: handle symlinks that cross file systems
303 for (iterator I = overlays_begin(), E = overlays_end(); I != E; ++I) {
304 ErrorOr<Status> Status = (*I)->status(Path);
305 if (Status || Status.getError() != llvm::errc::no_such_file_or_directory)
308 return make_error_code(llvm::errc::no_such_file_or_directory);
311 ErrorOr<std::unique_ptr<File>>
312 OverlayFileSystem::openFileForRead(const llvm::Twine &Path) {
313 // FIXME: handle symlinks that cross file systems
314 for (iterator I = overlays_begin(), E = overlays_end(); I != E; ++I) {
315 auto Result = (*I)->openFileForRead(Path);
316 if (Result || Result.getError() != llvm::errc::no_such_file_or_directory)
319 return make_error_code(llvm::errc::no_such_file_or_directory);
322 llvm::ErrorOr<std::string>
323 OverlayFileSystem::getCurrentWorkingDirectory() const {
324 // All file systems are synchronized, just take the first working directory.
325 return FSList.front()->getCurrentWorkingDirectory();
328 OverlayFileSystem::setCurrentWorkingDirectory(const Twine &Path) {
329 for (auto &FS : FSList)
330 if (std::error_code EC = FS->setCurrentWorkingDirectory(Path))
332 return std::error_code();
335 clang::vfs::detail::DirIterImpl::~DirIterImpl() { }
338 class OverlayFSDirIterImpl : public clang::vfs::detail::DirIterImpl {
339 OverlayFileSystem &Overlays;
341 OverlayFileSystem::iterator CurrentFS;
342 directory_iterator CurrentDirIter;
343 llvm::StringSet<> SeenNames;
345 std::error_code incrementFS() {
346 assert(CurrentFS != Overlays.overlays_end() && "incrementing past end");
348 for (auto E = Overlays.overlays_end(); CurrentFS != E; ++CurrentFS) {
350 CurrentDirIter = (*CurrentFS)->dir_begin(Path, EC);
351 if (EC && EC != errc::no_such_file_or_directory)
353 if (CurrentDirIter != directory_iterator())
356 return std::error_code();
359 std::error_code incrementDirIter(bool IsFirstTime) {
360 assert((IsFirstTime || CurrentDirIter != directory_iterator()) &&
361 "incrementing past end");
364 CurrentDirIter.increment(EC);
365 if (!EC && CurrentDirIter == directory_iterator())
370 std::error_code incrementImpl(bool IsFirstTime) {
372 std::error_code EC = incrementDirIter(IsFirstTime);
373 if (EC || CurrentDirIter == directory_iterator()) {
374 CurrentEntry = Status();
377 CurrentEntry = *CurrentDirIter;
378 StringRef Name = llvm::sys::path::filename(CurrentEntry.getName());
379 if (SeenNames.insert(Name).second)
380 return EC; // name not seen before
382 llvm_unreachable("returned above");
386 OverlayFSDirIterImpl(const Twine &Path, OverlayFileSystem &FS,
388 : Overlays(FS), Path(Path.str()), CurrentFS(Overlays.overlays_begin()) {
389 CurrentDirIter = (*CurrentFS)->dir_begin(Path, EC);
390 EC = incrementImpl(true);
393 std::error_code increment() override { return incrementImpl(false); }
395 } // end anonymous namespace
397 directory_iterator OverlayFileSystem::dir_begin(const Twine &Dir,
398 std::error_code &EC) {
399 return directory_iterator(
400 std::make_shared<OverlayFSDirIterImpl>(Dir, *this, EC));
407 enum InMemoryNodeKind { IME_File, IME_Directory };
409 /// The in memory file system is a tree of Nodes. Every node can either be a
410 /// file or a directory.
413 InMemoryNodeKind Kind;
416 InMemoryNode(Status Stat, InMemoryNodeKind Kind)
417 : Stat(std::move(Stat)), Kind(Kind) {}
418 virtual ~InMemoryNode() {}
419 const Status &getStatus() const { return Stat; }
420 InMemoryNodeKind getKind() const { return Kind; }
421 virtual std::string toString(unsigned Indent) const = 0;
425 class InMemoryFile : public InMemoryNode {
426 std::unique_ptr<llvm::MemoryBuffer> Buffer;
429 InMemoryFile(Status Stat, std::unique_ptr<llvm::MemoryBuffer> Buffer)
430 : InMemoryNode(std::move(Stat), IME_File), Buffer(std::move(Buffer)) {}
432 llvm::MemoryBuffer *getBuffer() { return Buffer.get(); }
433 std::string toString(unsigned Indent) const override {
434 return (std::string(Indent, ' ') + getStatus().getName() + "\n").str();
436 static bool classof(const InMemoryNode *N) {
437 return N->getKind() == IME_File;
441 /// Adapt a InMemoryFile for VFS' File interface.
442 class InMemoryFileAdaptor : public File {
446 explicit InMemoryFileAdaptor(InMemoryFile &Node) : Node(Node) {}
448 llvm::ErrorOr<Status> status() override { return Node.getStatus(); }
449 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
450 getBuffer(const Twine &Name, int64_t FileSize, bool RequiresNullTerminator,
451 bool IsVolatile) override {
452 llvm::MemoryBuffer *Buf = Node.getBuffer();
453 return llvm::MemoryBuffer::getMemBuffer(
454 Buf->getBuffer(), Buf->getBufferIdentifier(), RequiresNullTerminator);
456 std::error_code close() override { return std::error_code(); }
458 } // end anonymous namespace
460 class InMemoryDirectory : public InMemoryNode {
461 std::map<std::string, std::unique_ptr<InMemoryNode>> Entries;
464 InMemoryDirectory(Status Stat)
465 : InMemoryNode(std::move(Stat), IME_Directory) {}
466 InMemoryNode *getChild(StringRef Name) {
467 auto I = Entries.find(Name);
468 if (I != Entries.end())
469 return I->second.get();
472 InMemoryNode *addChild(StringRef Name, std::unique_ptr<InMemoryNode> Child) {
473 return Entries.insert(make_pair(Name, std::move(Child)))
474 .first->second.get();
477 typedef decltype(Entries)::const_iterator const_iterator;
478 const_iterator begin() const { return Entries.begin(); }
479 const_iterator end() const { return Entries.end(); }
481 std::string toString(unsigned Indent) const override {
483 (std::string(Indent, ' ') + getStatus().getName() + "\n").str();
484 for (const auto &Entry : Entries) {
485 Result += Entry.second->toString(Indent + 2);
489 static bool classof(const InMemoryNode *N) {
490 return N->getKind() == IME_Directory;
495 InMemoryFileSystem::InMemoryFileSystem(bool UseNormalizedPaths)
496 : Root(new detail::InMemoryDirectory(
497 Status("", getNextVirtualUniqueID(), llvm::sys::TimePoint<>(), 0, 0,
498 0, llvm::sys::fs::file_type::directory_file,
499 llvm::sys::fs::perms::all_all))),
500 UseNormalizedPaths(UseNormalizedPaths) {}
502 InMemoryFileSystem::~InMemoryFileSystem() {}
504 std::string InMemoryFileSystem::toString() const {
505 return Root->toString(/*Indent=*/0);
508 bool InMemoryFileSystem::addFile(const Twine &P, time_t ModificationTime,
509 std::unique_ptr<llvm::MemoryBuffer> Buffer) {
510 SmallString<128> Path;
513 // Fix up relative paths. This just prepends the current working directory.
514 std::error_code EC = makeAbsolute(Path);
518 if (useNormalizedPaths())
519 llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
524 detail::InMemoryDirectory *Dir = Root.get();
525 auto I = llvm::sys::path::begin(Path), E = llvm::sys::path::end(Path);
528 detail::InMemoryNode *Node = Dir->getChild(Name);
532 // End of the path, create a new file.
533 // FIXME: expose the status details in the interface.
534 Status Stat(P.str(), getNextVirtualUniqueID(),
535 llvm::sys::toTimePoint(ModificationTime), 0, 0,
536 Buffer->getBufferSize(),
537 llvm::sys::fs::file_type::regular_file,
538 llvm::sys::fs::all_all);
539 Dir->addChild(Name, llvm::make_unique<detail::InMemoryFile>(
540 std::move(Stat), std::move(Buffer)));
544 // Create a new directory. Use the path up to here.
545 // FIXME: expose the status details in the interface.
547 StringRef(Path.str().begin(), Name.end() - Path.str().begin()),
548 getNextVirtualUniqueID(), llvm::sys::toTimePoint(ModificationTime), 0,
549 0, Buffer->getBufferSize(), llvm::sys::fs::file_type::directory_file,
550 llvm::sys::fs::all_all);
551 Dir = cast<detail::InMemoryDirectory>(Dir->addChild(
552 Name, llvm::make_unique<detail::InMemoryDirectory>(std::move(Stat))));
556 if (auto *NewDir = dyn_cast<detail::InMemoryDirectory>(Node)) {
559 assert(isa<detail::InMemoryFile>(Node) &&
560 "Must be either file or directory!");
562 // Trying to insert a directory in place of a file.
566 // Return false only if the new file is different from the existing one.
567 return cast<detail::InMemoryFile>(Node)->getBuffer()->getBuffer() ==
573 bool InMemoryFileSystem::addFileNoOwn(const Twine &P, time_t ModificationTime,
574 llvm::MemoryBuffer *Buffer) {
575 return addFile(P, ModificationTime,
576 llvm::MemoryBuffer::getMemBuffer(
577 Buffer->getBuffer(), Buffer->getBufferIdentifier()));
580 static ErrorOr<detail::InMemoryNode *>
581 lookupInMemoryNode(const InMemoryFileSystem &FS, detail::InMemoryDirectory *Dir,
583 SmallString<128> Path;
586 // Fix up relative paths. This just prepends the current working directory.
587 std::error_code EC = FS.makeAbsolute(Path);
591 if (FS.useNormalizedPaths())
592 llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
597 auto I = llvm::sys::path::begin(Path), E = llvm::sys::path::end(Path);
599 detail::InMemoryNode *Node = Dir->getChild(*I);
602 return errc::no_such_file_or_directory;
604 // Return the file if it's at the end of the path.
605 if (auto File = dyn_cast<detail::InMemoryFile>(Node)) {
608 return errc::no_such_file_or_directory;
611 // Traverse directories.
612 Dir = cast<detail::InMemoryDirectory>(Node);
618 llvm::ErrorOr<Status> InMemoryFileSystem::status(const Twine &Path) {
619 auto Node = lookupInMemoryNode(*this, Root.get(), Path);
621 return (*Node)->getStatus();
622 return Node.getError();
625 llvm::ErrorOr<std::unique_ptr<File>>
626 InMemoryFileSystem::openFileForRead(const Twine &Path) {
627 auto Node = lookupInMemoryNode(*this, Root.get(), Path);
629 return Node.getError();
631 // When we have a file provide a heap-allocated wrapper for the memory buffer
632 // to match the ownership semantics for File.
633 if (auto *F = dyn_cast<detail::InMemoryFile>(*Node))
634 return std::unique_ptr<File>(new detail::InMemoryFileAdaptor(*F));
636 // FIXME: errc::not_a_file?
637 return make_error_code(llvm::errc::invalid_argument);
641 /// Adaptor from InMemoryDir::iterator to directory_iterator.
642 class InMemoryDirIterator : public clang::vfs::detail::DirIterImpl {
643 detail::InMemoryDirectory::const_iterator I;
644 detail::InMemoryDirectory::const_iterator E;
647 InMemoryDirIterator() {}
648 explicit InMemoryDirIterator(detail::InMemoryDirectory &Dir)
649 : I(Dir.begin()), E(Dir.end()) {
651 CurrentEntry = I->second->getStatus();
654 std::error_code increment() override {
656 // When we're at the end, make CurrentEntry invalid and DirIterImpl will do
658 CurrentEntry = I != E ? I->second->getStatus() : Status();
659 return std::error_code();
662 } // end anonymous namespace
664 directory_iterator InMemoryFileSystem::dir_begin(const Twine &Dir,
665 std::error_code &EC) {
666 auto Node = lookupInMemoryNode(*this, Root.get(), Dir);
668 EC = Node.getError();
669 return directory_iterator(std::make_shared<InMemoryDirIterator>());
672 if (auto *DirNode = dyn_cast<detail::InMemoryDirectory>(*Node))
673 return directory_iterator(std::make_shared<InMemoryDirIterator>(*DirNode));
675 EC = make_error_code(llvm::errc::not_a_directory);
676 return directory_iterator(std::make_shared<InMemoryDirIterator>());
679 std::error_code InMemoryFileSystem::setCurrentWorkingDirectory(const Twine &P) {
680 SmallString<128> Path;
683 // Fix up relative paths. This just prepends the current working directory.
684 std::error_code EC = makeAbsolute(Path);
688 if (useNormalizedPaths())
689 llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
692 WorkingDirectory = Path.str();
693 return std::error_code();
698 //===-----------------------------------------------------------------------===/
699 // RedirectingFileSystem implementation
700 //===-----------------------------------------------------------------------===/
709 /// \brief A single file or directory in the VFS.
716 Entry(EntryKind K, StringRef Name) : Kind(K), Name(Name) {}
717 StringRef getName() const { return Name; }
718 EntryKind getKind() const { return Kind; }
721 class RedirectingDirectoryEntry : public Entry {
722 std::vector<std::unique_ptr<Entry>> Contents;
726 RedirectingDirectoryEntry(StringRef Name,
727 std::vector<std::unique_ptr<Entry>> Contents,
729 : Entry(EK_Directory, Name), Contents(std::move(Contents)),
731 RedirectingDirectoryEntry(StringRef Name, Status S)
732 : Entry(EK_Directory, Name), S(std::move(S)) {}
733 Status getStatus() { return S; }
734 void addContent(std::unique_ptr<Entry> Content) {
735 Contents.push_back(std::move(Content));
737 Entry *getLastContent() const { return Contents.back().get(); }
738 typedef decltype(Contents)::iterator iterator;
739 iterator contents_begin() { return Contents.begin(); }
740 iterator contents_end() { return Contents.end(); }
741 static bool classof(const Entry *E) { return E->getKind() == EK_Directory; }
744 class RedirectingFileEntry : public Entry {
752 std::string ExternalContentsPath;
755 RedirectingFileEntry(StringRef Name, StringRef ExternalContentsPath,
757 : Entry(EK_File, Name), ExternalContentsPath(ExternalContentsPath),
759 StringRef getExternalContentsPath() const { return ExternalContentsPath; }
760 /// \brief whether to use the external path as the name for this file.
761 bool useExternalName(bool GlobalUseExternalName) const {
762 return UseName == NK_NotSet ? GlobalUseExternalName
763 : (UseName == NK_External);
765 NameKind getUseName() const { return UseName; }
766 static bool classof(const Entry *E) { return E->getKind() == EK_File; }
769 class RedirectingFileSystem;
771 class VFSFromYamlDirIterImpl : public clang::vfs::detail::DirIterImpl {
773 RedirectingFileSystem &FS;
774 RedirectingDirectoryEntry::iterator Current, End;
777 VFSFromYamlDirIterImpl(const Twine &Path, RedirectingFileSystem &FS,
778 RedirectingDirectoryEntry::iterator Begin,
779 RedirectingDirectoryEntry::iterator End,
780 std::error_code &EC);
781 std::error_code increment() override;
784 /// \brief A virtual file system parsed from a YAML file.
786 /// Currently, this class allows creating virtual directories and mapping
787 /// virtual file paths to existing external files, available in \c ExternalFS.
789 /// The basic structure of the parsed file is:
792 /// 'version': <version number>,
793 /// <optional configuration>
795 /// <directory entries>
800 /// All configuration options are optional.
801 /// 'case-sensitive': <boolean, default=true>
802 /// 'use-external-names': <boolean, default=true>
803 /// 'overlay-relative': <boolean, default=false>
804 /// 'ignore-non-existent-contents': <boolean, default=true>
806 /// Virtual directories are represented as
809 /// 'type': 'directory',
810 /// 'name': <string>,
811 /// 'contents': [ <file or directory entries> ]
815 /// The default attributes for virtual directories are:
817 /// MTime = now() when created
821 /// UniqueID = unspecified unique value
824 /// Re-mapped files are represented as
828 /// 'name': <string>,
829 /// 'use-external-name': <boolean> # Optional
830 /// 'external-contents': <path to external file>)
834 /// and inherit their attributes from the external contents.
836 /// In both cases, the 'name' field may contain multiple path components (e.g.
837 /// /path/to/file). However, any directory that contains more than one child
838 /// must be uniquely represented by a directory entry.
839 class RedirectingFileSystem : public vfs::FileSystem {
840 /// The root(s) of the virtual file system.
841 std::vector<std::unique_ptr<Entry>> Roots;
842 /// \brief The file system to use for external references.
843 IntrusiveRefCntPtr<FileSystem> ExternalFS;
844 /// If IsRelativeOverlay is set, this represents the directory
845 /// path that should be prefixed to each 'external-contents' entry
846 /// when reading from YAML files.
847 std::string ExternalContentsPrefixDir;
849 /// @name Configuration
852 /// \brief Whether to perform case-sensitive comparisons.
854 /// Currently, case-insensitive matching only works correctly with ASCII.
855 bool CaseSensitive = true;
857 /// IsRelativeOverlay marks whether a IsExternalContentsPrefixDir path must
858 /// be prefixed in every 'external-contents' when reading from YAML files.
859 bool IsRelativeOverlay = false;
861 /// \brief Whether to use to use the value of 'external-contents' for the
862 /// names of files. This global value is overridable on a per-file basis.
863 bool UseExternalNames = true;
865 /// \brief Whether an invalid path obtained via 'external-contents' should
866 /// cause iteration on the VFS to stop. If 'true', the VFS should ignore
867 /// the entry and continue with the next. Allows YAML files to be shared
868 /// across multiple compiler invocations regardless of prior existent
869 /// paths in 'external-contents'. This global value is overridable on a
871 bool IgnoreNonExistentContents = true;
874 /// Virtual file paths and external files could be canonicalized without "..",
875 /// "." and "./" in their paths. FIXME: some unittests currently fail on
876 /// win32 when using remove_dots and remove_leading_dotslash on paths.
877 bool UseCanonicalizedPaths =
884 friend class RedirectingFileSystemParser;
887 RedirectingFileSystem(IntrusiveRefCntPtr<FileSystem> ExternalFS)
888 : ExternalFS(std::move(ExternalFS)) {}
890 /// \brief Looks up the path <tt>[Start, End)</tt> in \p From, possibly
891 /// recursing into the contents of \p From if it is a directory.
892 ErrorOr<Entry *> lookupPath(sys::path::const_iterator Start,
893 sys::path::const_iterator End, Entry *From);
895 /// \brief Get the status of a given an \c Entry.
896 ErrorOr<Status> status(const Twine &Path, Entry *E);
899 /// \brief Looks up \p Path in \c Roots.
900 ErrorOr<Entry *> lookupPath(const Twine &Path);
902 /// \brief Parses \p Buffer, which is expected to be in YAML format and
903 /// returns a virtual file system representing its contents.
904 static RedirectingFileSystem *
905 create(std::unique_ptr<MemoryBuffer> Buffer,
906 SourceMgr::DiagHandlerTy DiagHandler, StringRef YAMLFilePath,
907 void *DiagContext, IntrusiveRefCntPtr<FileSystem> ExternalFS);
909 ErrorOr<Status> status(const Twine &Path) override;
910 ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
912 llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override {
913 return ExternalFS->getCurrentWorkingDirectory();
915 std::error_code setCurrentWorkingDirectory(const Twine &Path) override {
916 return ExternalFS->setCurrentWorkingDirectory(Path);
919 directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override{
920 ErrorOr<Entry *> E = lookupPath(Dir);
923 return directory_iterator();
925 ErrorOr<Status> S = status(Dir, *E);
928 return directory_iterator();
930 if (!S->isDirectory()) {
931 EC = std::error_code(static_cast<int>(errc::not_a_directory),
932 std::system_category());
933 return directory_iterator();
936 auto *D = cast<RedirectingDirectoryEntry>(*E);
937 return directory_iterator(std::make_shared<VFSFromYamlDirIterImpl>(Dir,
938 *this, D->contents_begin(), D->contents_end(), EC));
941 void setExternalContentsPrefixDir(StringRef PrefixDir) {
942 ExternalContentsPrefixDir = PrefixDir.str();
945 StringRef getExternalContentsPrefixDir() const {
946 return ExternalContentsPrefixDir;
949 bool ignoreNonExistentContents() const {
950 return IgnoreNonExistentContents;
953 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
954 LLVM_DUMP_METHOD void dump() const {
955 for (const std::unique_ptr<Entry> &Root : Roots)
956 dumpEntry(Root.get());
959 LLVM_DUMP_METHOD void dumpEntry(Entry *E, int NumSpaces = 0) const {
960 StringRef Name = E->getName();
961 for (int i = 0, e = NumSpaces; i < e; ++i)
963 dbgs() << "'" << Name.str().c_str() << "'" << "\n";
965 if (E->getKind() == EK_Directory) {
966 auto *DE = dyn_cast<RedirectingDirectoryEntry>(E);
967 assert(DE && "Should be a directory");
969 for (std::unique_ptr<Entry> &SubEntry :
970 llvm::make_range(DE->contents_begin(), DE->contents_end()))
971 dumpEntry(SubEntry.get(), NumSpaces+2);
978 /// \brief A helper class to hold the common YAML parsing state.
979 class RedirectingFileSystemParser {
980 yaml::Stream &Stream;
982 void error(yaml::Node *N, const Twine &Msg) {
983 Stream.printError(N, Msg);
987 bool parseScalarString(yaml::Node *N, StringRef &Result,
988 SmallVectorImpl<char> &Storage) {
989 yaml::ScalarNode *S = dyn_cast<yaml::ScalarNode>(N);
991 error(N, "expected string");
994 Result = S->getValue(Storage);
999 bool parseScalarBool(yaml::Node *N, bool &Result) {
1000 SmallString<5> Storage;
1002 if (!parseScalarString(N, Value, Storage))
1005 if (Value.equals_lower("true") || Value.equals_lower("on") ||
1006 Value.equals_lower("yes") || Value == "1") {
1009 } else if (Value.equals_lower("false") || Value.equals_lower("off") ||
1010 Value.equals_lower("no") || Value == "0") {
1015 error(N, "expected boolean value");
1020 KeyStatus(bool Required=false) : Required(Required), Seen(false) {}
1024 typedef std::pair<StringRef, KeyStatus> KeyStatusPair;
1027 bool checkDuplicateOrUnknownKey(yaml::Node *KeyNode, StringRef Key,
1028 DenseMap<StringRef, KeyStatus> &Keys) {
1029 if (!Keys.count(Key)) {
1030 error(KeyNode, "unknown key");
1033 KeyStatus &S = Keys[Key];
1035 error(KeyNode, Twine("duplicate key '") + Key + "'");
1043 bool checkMissingKeys(yaml::Node *Obj, DenseMap<StringRef, KeyStatus> &Keys) {
1044 for (DenseMap<StringRef, KeyStatus>::iterator I = Keys.begin(),
1047 if (I->second.Required && !I->second.Seen) {
1048 error(Obj, Twine("missing key '") + I->first + "'");
1055 Entry *lookupOrCreateEntry(RedirectingFileSystem *FS, StringRef Name,
1056 Entry *ParentEntry = nullptr) {
1057 if (!ParentEntry) { // Look for a existent root
1058 for (const std::unique_ptr<Entry> &Root : FS->Roots) {
1059 if (Name.equals(Root->getName())) {
1060 ParentEntry = Root.get();
1064 } else { // Advance to the next component
1065 auto *DE = dyn_cast<RedirectingDirectoryEntry>(ParentEntry);
1066 for (std::unique_ptr<Entry> &Content :
1067 llvm::make_range(DE->contents_begin(), DE->contents_end())) {
1068 auto *DirContent = dyn_cast<RedirectingDirectoryEntry>(Content.get());
1069 if (DirContent && Name.equals(Content->getName()))
1074 // ... or create a new one
1075 std::unique_ptr<Entry> E = llvm::make_unique<RedirectingDirectoryEntry>(
1077 Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
1078 0, 0, 0, file_type::directory_file, sys::fs::all_all));
1080 if (!ParentEntry) { // Add a new root to the overlay
1081 FS->Roots.push_back(std::move(E));
1082 ParentEntry = FS->Roots.back().get();
1086 auto *DE = dyn_cast<RedirectingDirectoryEntry>(ParentEntry);
1087 DE->addContent(std::move(E));
1088 return DE->getLastContent();
1091 void uniqueOverlayTree(RedirectingFileSystem *FS, Entry *SrcE,
1092 Entry *NewParentE = nullptr) {
1093 StringRef Name = SrcE->getName();
1094 switch (SrcE->getKind()) {
1095 case EK_Directory: {
1096 auto *DE = dyn_cast<RedirectingDirectoryEntry>(SrcE);
1097 assert(DE && "Must be a directory");
1098 // Empty directories could be present in the YAML as a way to
1099 // describe a file for a current directory after some of its subdir
1100 // is parsed. This only leads to redundant walks, ignore it.
1102 NewParentE = lookupOrCreateEntry(FS, Name, NewParentE);
1103 for (std::unique_ptr<Entry> &SubEntry :
1104 llvm::make_range(DE->contents_begin(), DE->contents_end()))
1105 uniqueOverlayTree(FS, SubEntry.get(), NewParentE);
1109 auto *FE = dyn_cast<RedirectingFileEntry>(SrcE);
1110 assert(FE && "Must be a file");
1111 assert(NewParentE && "Parent entry must exist");
1112 auto *DE = dyn_cast<RedirectingDirectoryEntry>(NewParentE);
1113 DE->addContent(llvm::make_unique<RedirectingFileEntry>(
1114 Name, FE->getExternalContentsPath(), FE->getUseName()));
1120 std::unique_ptr<Entry> parseEntry(yaml::Node *N, RedirectingFileSystem *FS) {
1121 yaml::MappingNode *M = dyn_cast<yaml::MappingNode>(N);
1123 error(N, "expected mapping node for file or directory entry");
1127 KeyStatusPair Fields[] = {
1128 KeyStatusPair("name", true),
1129 KeyStatusPair("type", true),
1130 KeyStatusPair("contents", false),
1131 KeyStatusPair("external-contents", false),
1132 KeyStatusPair("use-external-name", false),
1135 DenseMap<StringRef, KeyStatus> Keys(std::begin(Fields), std::end(Fields));
1137 bool HasContents = false; // external or otherwise
1138 std::vector<std::unique_ptr<Entry>> EntryArrayContents;
1139 std::string ExternalContentsPath;
1141 auto UseExternalName = RedirectingFileEntry::NK_NotSet;
1144 for (yaml::MappingNode::iterator I = M->begin(), E = M->end(); I != E;
1147 // Reuse the buffer for key and value, since we don't look at key after
1149 SmallString<256> Buffer;
1150 if (!parseScalarString(I->getKey(), Key, Buffer))
1153 if (!checkDuplicateOrUnknownKey(I->getKey(), Key, Keys))
1157 if (Key == "name") {
1158 if (!parseScalarString(I->getValue(), Value, Buffer))
1161 if (FS->UseCanonicalizedPaths) {
1162 SmallString<256> Path(Value);
1163 // Guarantee that old YAML files containing paths with ".." and "."
1164 // are properly canonicalized before read into the VFS.
1165 Path = sys::path::remove_leading_dotslash(Path);
1166 sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
1171 } else if (Key == "type") {
1172 if (!parseScalarString(I->getValue(), Value, Buffer))
1174 if (Value == "file")
1176 else if (Value == "directory")
1177 Kind = EK_Directory;
1179 error(I->getValue(), "unknown value for 'type'");
1182 } else if (Key == "contents") {
1185 "entry already has 'contents' or 'external-contents'");
1189 yaml::SequenceNode *Contents =
1190 dyn_cast<yaml::SequenceNode>(I->getValue());
1192 // FIXME: this is only for directories, what about files?
1193 error(I->getValue(), "expected array");
1197 for (yaml::SequenceNode::iterator I = Contents->begin(),
1198 E = Contents->end();
1200 if (std::unique_ptr<Entry> E = parseEntry(&*I, FS))
1201 EntryArrayContents.push_back(std::move(E));
1205 } else if (Key == "external-contents") {
1208 "entry already has 'contents' or 'external-contents'");
1212 if (!parseScalarString(I->getValue(), Value, Buffer))
1215 SmallString<256> FullPath;
1216 if (FS->IsRelativeOverlay) {
1217 FullPath = FS->getExternalContentsPrefixDir();
1218 assert(!FullPath.empty() &&
1219 "External contents prefix directory must exist");
1220 llvm::sys::path::append(FullPath, Value);
1225 if (FS->UseCanonicalizedPaths) {
1226 // Guarantee that old YAML files containing paths with ".." and "."
1227 // are properly canonicalized before read into the VFS.
1228 FullPath = sys::path::remove_leading_dotslash(FullPath);
1229 sys::path::remove_dots(FullPath, /*remove_dot_dot=*/true);
1231 ExternalContentsPath = FullPath.str();
1232 } else if (Key == "use-external-name") {
1234 if (!parseScalarBool(I->getValue(), Val))
1236 UseExternalName = Val ? RedirectingFileEntry::NK_External
1237 : RedirectingFileEntry::NK_Virtual;
1239 llvm_unreachable("key missing from Keys");
1243 if (Stream.failed())
1246 // check for missing keys
1248 error(N, "missing key 'contents' or 'external-contents'");
1251 if (!checkMissingKeys(N, Keys))
1254 // check invalid configuration
1255 if (Kind == EK_Directory &&
1256 UseExternalName != RedirectingFileEntry::NK_NotSet) {
1257 error(N, "'use-external-name' is not supported for directories");
1261 // Remove trailing slash(es), being careful not to remove the root path
1262 StringRef Trimmed(Name);
1263 size_t RootPathLen = sys::path::root_path(Trimmed).size();
1264 while (Trimmed.size() > RootPathLen &&
1265 sys::path::is_separator(Trimmed.back()))
1266 Trimmed = Trimmed.slice(0, Trimmed.size()-1);
1267 // Get the last component
1268 StringRef LastComponent = sys::path::filename(Trimmed);
1270 std::unique_ptr<Entry> Result;
1273 Result = llvm::make_unique<RedirectingFileEntry>(
1274 LastComponent, std::move(ExternalContentsPath), UseExternalName);
1277 Result = llvm::make_unique<RedirectingDirectoryEntry>(
1278 LastComponent, std::move(EntryArrayContents),
1279 Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
1280 0, 0, 0, file_type::directory_file, sys::fs::all_all));
1284 StringRef Parent = sys::path::parent_path(Trimmed);
1288 // if 'name' contains multiple components, create implicit directory entries
1289 for (sys::path::reverse_iterator I = sys::path::rbegin(Parent),
1290 E = sys::path::rend(Parent);
1292 std::vector<std::unique_ptr<Entry>> Entries;
1293 Entries.push_back(std::move(Result));
1294 Result = llvm::make_unique<RedirectingDirectoryEntry>(
1295 *I, std::move(Entries),
1296 Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
1297 0, 0, 0, file_type::directory_file, sys::fs::all_all));
1303 RedirectingFileSystemParser(yaml::Stream &S) : Stream(S) {}
1306 bool parse(yaml::Node *Root, RedirectingFileSystem *FS) {
1307 yaml::MappingNode *Top = dyn_cast<yaml::MappingNode>(Root);
1309 error(Root, "expected mapping node");
1313 KeyStatusPair Fields[] = {
1314 KeyStatusPair("version", true),
1315 KeyStatusPair("case-sensitive", false),
1316 KeyStatusPair("use-external-names", false),
1317 KeyStatusPair("overlay-relative", false),
1318 KeyStatusPair("ignore-non-existent-contents", false),
1319 KeyStatusPair("roots", true),
1322 DenseMap<StringRef, KeyStatus> Keys(std::begin(Fields), std::end(Fields));
1323 std::vector<std::unique_ptr<Entry>> RootEntries;
1325 // Parse configuration and 'roots'
1326 for (yaml::MappingNode::iterator I = Top->begin(), E = Top->end(); I != E;
1328 SmallString<10> KeyBuffer;
1330 if (!parseScalarString(I->getKey(), Key, KeyBuffer))
1333 if (!checkDuplicateOrUnknownKey(I->getKey(), Key, Keys))
1336 if (Key == "roots") {
1337 yaml::SequenceNode *Roots = dyn_cast<yaml::SequenceNode>(I->getValue());
1339 error(I->getValue(), "expected array");
1343 for (yaml::SequenceNode::iterator I = Roots->begin(), E = Roots->end();
1345 if (std::unique_ptr<Entry> E = parseEntry(&*I, FS))
1346 RootEntries.push_back(std::move(E));
1350 } else if (Key == "version") {
1351 StringRef VersionString;
1352 SmallString<4> Storage;
1353 if (!parseScalarString(I->getValue(), VersionString, Storage))
1356 if (VersionString.getAsInteger<int>(10, Version)) {
1357 error(I->getValue(), "expected integer");
1361 error(I->getValue(), "invalid version number");
1365 error(I->getValue(), "version mismatch, expected 0");
1368 } else if (Key == "case-sensitive") {
1369 if (!parseScalarBool(I->getValue(), FS->CaseSensitive))
1371 } else if (Key == "overlay-relative") {
1372 if (!parseScalarBool(I->getValue(), FS->IsRelativeOverlay))
1374 } else if (Key == "use-external-names") {
1375 if (!parseScalarBool(I->getValue(), FS->UseExternalNames))
1377 } else if (Key == "ignore-non-existent-contents") {
1378 if (!parseScalarBool(I->getValue(), FS->IgnoreNonExistentContents))
1381 llvm_unreachable("key missing from Keys");
1385 if (Stream.failed())
1388 if (!checkMissingKeys(Top, Keys))
1391 // Now that we sucessefully parsed the YAML file, canonicalize the internal
1392 // representation to a proper directory tree so that we can search faster
1394 for (std::unique_ptr<Entry> &E : RootEntries)
1395 uniqueOverlayTree(FS, E.get());
1400 } // end of anonymous namespace
1402 Entry::~Entry() = default;
1404 RedirectingFileSystem *
1405 RedirectingFileSystem::create(std::unique_ptr<MemoryBuffer> Buffer,
1406 SourceMgr::DiagHandlerTy DiagHandler,
1407 StringRef YAMLFilePath, void *DiagContext,
1408 IntrusiveRefCntPtr<FileSystem> ExternalFS) {
1411 yaml::Stream Stream(Buffer->getMemBufferRef(), SM);
1413 SM.setDiagHandler(DiagHandler, DiagContext);
1414 yaml::document_iterator DI = Stream.begin();
1415 yaml::Node *Root = DI->getRoot();
1416 if (DI == Stream.end() || !Root) {
1417 SM.PrintMessage(SMLoc(), SourceMgr::DK_Error, "expected root node");
1421 RedirectingFileSystemParser P(Stream);
1423 std::unique_ptr<RedirectingFileSystem> FS(
1424 new RedirectingFileSystem(std::move(ExternalFS)));
1426 if (!YAMLFilePath.empty()) {
1427 // Use the YAML path from -ivfsoverlay to compute the dir to be prefixed
1428 // to each 'external-contents' path.
1431 // -ivfsoverlay dummy.cache/vfs/vfs.yaml
1433 // FS->ExternalContentsPrefixDir => /<absolute_path_to>/dummy.cache/vfs
1435 SmallString<256> OverlayAbsDir = sys::path::parent_path(YAMLFilePath);
1436 std::error_code EC = llvm::sys::fs::make_absolute(OverlayAbsDir);
1437 assert(!EC && "Overlay dir final path must be absolute");
1439 FS->setExternalContentsPrefixDir(OverlayAbsDir);
1442 if (!P.parse(Root, FS.get()))
1445 return FS.release();
1448 ErrorOr<Entry *> RedirectingFileSystem::lookupPath(const Twine &Path_) {
1449 SmallString<256> Path;
1450 Path_.toVector(Path);
1452 // Handle relative paths
1453 if (std::error_code EC = makeAbsolute(Path))
1456 // Canonicalize path by removing ".", "..", "./", etc components. This is
1457 // a VFS request, do bot bother about symlinks in the path components
1458 // but canonicalize in order to perform the correct entry search.
1459 if (UseCanonicalizedPaths) {
1460 Path = sys::path::remove_leading_dotslash(Path);
1461 sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
1465 return make_error_code(llvm::errc::invalid_argument);
1467 sys::path::const_iterator Start = sys::path::begin(Path);
1468 sys::path::const_iterator End = sys::path::end(Path);
1469 for (const std::unique_ptr<Entry> &Root : Roots) {
1470 ErrorOr<Entry *> Result = lookupPath(Start, End, Root.get());
1471 if (Result || Result.getError() != llvm::errc::no_such_file_or_directory)
1474 return make_error_code(llvm::errc::no_such_file_or_directory);
1478 RedirectingFileSystem::lookupPath(sys::path::const_iterator Start,
1479 sys::path::const_iterator End, Entry *From) {
1480 #ifndef LLVM_ON_WIN32
1481 assert(!isTraversalComponent(*Start) &&
1482 !isTraversalComponent(From->getName()) &&
1483 "Paths should not contain traversal components");
1485 // FIXME: this is here to support windows, remove it once canonicalized
1486 // paths become globally default.
1487 if (Start->equals("."))
1491 StringRef FromName = From->getName();
1493 // Forward the search to the next component in case this is an empty one.
1494 if (!FromName.empty()) {
1495 if (CaseSensitive ? !Start->equals(FromName)
1496 : !Start->equals_lower(FromName))
1498 return make_error_code(llvm::errc::no_such_file_or_directory);
1508 auto *DE = dyn_cast<RedirectingDirectoryEntry>(From);
1510 return make_error_code(llvm::errc::not_a_directory);
1512 for (const std::unique_ptr<Entry> &DirEntry :
1513 llvm::make_range(DE->contents_begin(), DE->contents_end())) {
1514 ErrorOr<Entry *> Result = lookupPath(Start, End, DirEntry.get());
1515 if (Result || Result.getError() != llvm::errc::no_such_file_or_directory)
1518 return make_error_code(llvm::errc::no_such_file_or_directory);
1521 static Status getRedirectedFileStatus(const Twine &Path, bool UseExternalNames,
1522 Status ExternalStatus) {
1523 Status S = ExternalStatus;
1524 if (!UseExternalNames)
1525 S = Status::copyWithNewName(S, Path.str());
1526 S.IsVFSMapped = true;
1530 ErrorOr<Status> RedirectingFileSystem::status(const Twine &Path, Entry *E) {
1531 assert(E != nullptr);
1532 if (auto *F = dyn_cast<RedirectingFileEntry>(E)) {
1533 ErrorOr<Status> S = ExternalFS->status(F->getExternalContentsPath());
1534 assert(!S || S->getName() == F->getExternalContentsPath());
1536 return getRedirectedFileStatus(Path, F->useExternalName(UseExternalNames),
1539 } else { // directory
1540 auto *DE = cast<RedirectingDirectoryEntry>(E);
1541 return Status::copyWithNewName(DE->getStatus(), Path.str());
1545 ErrorOr<Status> RedirectingFileSystem::status(const Twine &Path) {
1546 ErrorOr<Entry *> Result = lookupPath(Path);
1548 return Result.getError();
1549 return status(Path, *Result);
1553 /// Provide a file wrapper with an overriden status.
1554 class FileWithFixedStatus : public File {
1555 std::unique_ptr<File> InnerFile;
1559 FileWithFixedStatus(std::unique_ptr<File> InnerFile, Status S)
1560 : InnerFile(std::move(InnerFile)), S(std::move(S)) {}
1562 ErrorOr<Status> status() override { return S; }
1563 ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
1564 getBuffer(const Twine &Name, int64_t FileSize, bool RequiresNullTerminator,
1565 bool IsVolatile) override {
1566 return InnerFile->getBuffer(Name, FileSize, RequiresNullTerminator,
1569 std::error_code close() override { return InnerFile->close(); }
1571 } // end anonymous namespace
1573 ErrorOr<std::unique_ptr<File>>
1574 RedirectingFileSystem::openFileForRead(const Twine &Path) {
1575 ErrorOr<Entry *> E = lookupPath(Path);
1577 return E.getError();
1579 auto *F = dyn_cast<RedirectingFileEntry>(*E);
1580 if (!F) // FIXME: errc::not_a_file?
1581 return make_error_code(llvm::errc::invalid_argument);
1583 auto Result = ExternalFS->openFileForRead(F->getExternalContentsPath());
1587 auto ExternalStatus = (*Result)->status();
1588 if (!ExternalStatus)
1589 return ExternalStatus.getError();
1591 // FIXME: Update the status with the name and VFSMapped.
1592 Status S = getRedirectedFileStatus(Path, F->useExternalName(UseExternalNames),
1594 return std::unique_ptr<File>(
1595 llvm::make_unique<FileWithFixedStatus>(std::move(*Result), S));
1598 IntrusiveRefCntPtr<FileSystem>
1599 vfs::getVFSFromYAML(std::unique_ptr<MemoryBuffer> Buffer,
1600 SourceMgr::DiagHandlerTy DiagHandler,
1601 StringRef YAMLFilePath,
1603 IntrusiveRefCntPtr<FileSystem> ExternalFS) {
1604 return RedirectingFileSystem::create(std::move(Buffer), DiagHandler,
1605 YAMLFilePath, DiagContext,
1606 std::move(ExternalFS));
1609 static void getVFSEntries(Entry *SrcE, SmallVectorImpl<StringRef> &Path,
1610 SmallVectorImpl<YAMLVFSEntry> &Entries) {
1611 auto Kind = SrcE->getKind();
1612 if (Kind == EK_Directory) {
1613 auto *DE = dyn_cast<RedirectingDirectoryEntry>(SrcE);
1614 assert(DE && "Must be a directory");
1615 for (std::unique_ptr<Entry> &SubEntry :
1616 llvm::make_range(DE->contents_begin(), DE->contents_end())) {
1617 Path.push_back(SubEntry->getName());
1618 getVFSEntries(SubEntry.get(), Path, Entries);
1624 assert(Kind == EK_File && "Must be a EK_File");
1625 auto *FE = dyn_cast<RedirectingFileEntry>(SrcE);
1626 assert(FE && "Must be a file");
1627 SmallString<128> VPath;
1628 for (auto &Comp : Path)
1629 llvm::sys::path::append(VPath, Comp);
1630 Entries.push_back(YAMLVFSEntry(VPath.c_str(), FE->getExternalContentsPath()));
1633 void vfs::collectVFSFromYAML(std::unique_ptr<MemoryBuffer> Buffer,
1634 SourceMgr::DiagHandlerTy DiagHandler,
1635 StringRef YAMLFilePath,
1636 SmallVectorImpl<YAMLVFSEntry> &CollectedEntries,
1638 IntrusiveRefCntPtr<FileSystem> ExternalFS) {
1639 RedirectingFileSystem *VFS = RedirectingFileSystem::create(
1640 std::move(Buffer), DiagHandler, YAMLFilePath, DiagContext,
1641 std::move(ExternalFS));
1642 ErrorOr<Entry *> RootE = VFS->lookupPath("/");
1645 SmallVector<StringRef, 8> Components;
1646 Components.push_back("/");
1647 getVFSEntries(*RootE, Components, CollectedEntries);
1650 UniqueID vfs::getNextVirtualUniqueID() {
1651 static std::atomic<unsigned> UID;
1652 unsigned ID = ++UID;
1653 // The following assumes that uint64_t max will never collide with a real
1654 // dev_t value from the OS.
1655 return UniqueID(std::numeric_limits<uint64_t>::max(), ID);
1658 void YAMLVFSWriter::addFileMapping(StringRef VirtualPath, StringRef RealPath) {
1659 assert(sys::path::is_absolute(VirtualPath) && "virtual path not absolute");
1660 assert(sys::path::is_absolute(RealPath) && "real path not absolute");
1661 assert(!pathHasTraversal(VirtualPath) && "path traversal is not supported");
1662 Mappings.emplace_back(VirtualPath, RealPath);
1667 llvm::raw_ostream &OS;
1668 SmallVector<StringRef, 16> DirStack;
1669 inline unsigned getDirIndent() { return 4 * DirStack.size(); }
1670 inline unsigned getFileIndent() { return 4 * (DirStack.size() + 1); }
1671 bool containedIn(StringRef Parent, StringRef Path);
1672 StringRef containedPart(StringRef Parent, StringRef Path);
1673 void startDirectory(StringRef Path);
1674 void endDirectory();
1675 void writeEntry(StringRef VPath, StringRef RPath);
1678 JSONWriter(llvm::raw_ostream &OS) : OS(OS) {}
1679 void write(ArrayRef<YAMLVFSEntry> Entries, Optional<bool> UseExternalNames,
1680 Optional<bool> IsCaseSensitive, Optional<bool> IsOverlayRelative,
1681 Optional<bool> IgnoreNonExistentContents, StringRef OverlayDir);
1685 bool JSONWriter::containedIn(StringRef Parent, StringRef Path) {
1686 using namespace llvm::sys;
1687 // Compare each path component.
1688 auto IParent = path::begin(Parent), EParent = path::end(Parent);
1689 for (auto IChild = path::begin(Path), EChild = path::end(Path);
1690 IParent != EParent && IChild != EChild; ++IParent, ++IChild) {
1691 if (*IParent != *IChild)
1694 // Have we exhausted the parent path?
1695 return IParent == EParent;
1698 StringRef JSONWriter::containedPart(StringRef Parent, StringRef Path) {
1699 assert(!Parent.empty());
1700 assert(containedIn(Parent, Path));
1701 return Path.slice(Parent.size() + 1, StringRef::npos);
1704 void JSONWriter::startDirectory(StringRef Path) {
1706 DirStack.empty() ? Path : containedPart(DirStack.back(), Path);
1707 DirStack.push_back(Path);
1708 unsigned Indent = getDirIndent();
1709 OS.indent(Indent) << "{\n";
1710 OS.indent(Indent + 2) << "'type': 'directory',\n";
1711 OS.indent(Indent + 2) << "'name': \"" << llvm::yaml::escape(Name) << "\",\n";
1712 OS.indent(Indent + 2) << "'contents': [\n";
1715 void JSONWriter::endDirectory() {
1716 unsigned Indent = getDirIndent();
1717 OS.indent(Indent + 2) << "]\n";
1718 OS.indent(Indent) << "}";
1720 DirStack.pop_back();
1723 void JSONWriter::writeEntry(StringRef VPath, StringRef RPath) {
1724 unsigned Indent = getFileIndent();
1725 OS.indent(Indent) << "{\n";
1726 OS.indent(Indent + 2) << "'type': 'file',\n";
1727 OS.indent(Indent + 2) << "'name': \"" << llvm::yaml::escape(VPath) << "\",\n";
1728 OS.indent(Indent + 2) << "'external-contents': \""
1729 << llvm::yaml::escape(RPath) << "\"\n";
1730 OS.indent(Indent) << "}";
1733 void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
1734 Optional<bool> UseExternalNames,
1735 Optional<bool> IsCaseSensitive,
1736 Optional<bool> IsOverlayRelative,
1737 Optional<bool> IgnoreNonExistentContents,
1738 StringRef OverlayDir) {
1739 using namespace llvm::sys;
1743 if (IsCaseSensitive.hasValue())
1744 OS << " 'case-sensitive': '"
1745 << (IsCaseSensitive.getValue() ? "true" : "false") << "',\n";
1746 if (UseExternalNames.hasValue())
1747 OS << " 'use-external-names': '"
1748 << (UseExternalNames.getValue() ? "true" : "false") << "',\n";
1749 bool UseOverlayRelative = false;
1750 if (IsOverlayRelative.hasValue()) {
1751 UseOverlayRelative = IsOverlayRelative.getValue();
1752 OS << " 'overlay-relative': '"
1753 << (UseOverlayRelative ? "true" : "false") << "',\n";
1755 if (IgnoreNonExistentContents.hasValue())
1756 OS << " 'ignore-non-existent-contents': '"
1757 << (IgnoreNonExistentContents.getValue() ? "true" : "false") << "',\n";
1758 OS << " 'roots': [\n";
1760 if (!Entries.empty()) {
1761 const YAMLVFSEntry &Entry = Entries.front();
1762 startDirectory(path::parent_path(Entry.VPath));
1764 StringRef RPath = Entry.RPath;
1765 if (UseOverlayRelative) {
1766 unsigned OverlayDirLen = OverlayDir.size();
1767 assert(RPath.substr(0, OverlayDirLen) == OverlayDir &&
1768 "Overlay dir must be contained in RPath");
1769 RPath = RPath.slice(OverlayDirLen, RPath.size());
1772 writeEntry(path::filename(Entry.VPath), RPath);
1774 for (const auto &Entry : Entries.slice(1)) {
1775 StringRef Dir = path::parent_path(Entry.VPath);
1776 if (Dir == DirStack.back())
1779 while (!DirStack.empty() && !containedIn(DirStack.back(), Dir)) {
1784 startDirectory(Dir);
1786 StringRef RPath = Entry.RPath;
1787 if (UseOverlayRelative) {
1788 unsigned OverlayDirLen = OverlayDir.size();
1789 assert(RPath.substr(0, OverlayDirLen) == OverlayDir &&
1790 "Overlay dir must be contained in RPath");
1791 RPath = RPath.slice(OverlayDirLen, RPath.size());
1793 writeEntry(path::filename(Entry.VPath), RPath);
1796 while (!DirStack.empty()) {
1807 void YAMLVFSWriter::write(llvm::raw_ostream &OS) {
1808 std::sort(Mappings.begin(), Mappings.end(),
1809 [](const YAMLVFSEntry &LHS, const YAMLVFSEntry &RHS) {
1810 return LHS.VPath < RHS.VPath;
1813 JSONWriter(OS).write(Mappings, UseExternalNames, IsCaseSensitive,
1814 IsOverlayRelative, IgnoreNonExistentContents,
1818 VFSFromYamlDirIterImpl::VFSFromYamlDirIterImpl(
1819 const Twine &_Path, RedirectingFileSystem &FS,
1820 RedirectingDirectoryEntry::iterator Begin,
1821 RedirectingDirectoryEntry::iterator End, std::error_code &EC)
1822 : Dir(_Path.str()), FS(FS), Current(Begin), End(End) {
1823 while (Current != End) {
1824 SmallString<128> PathStr(Dir);
1825 llvm::sys::path::append(PathStr, (*Current)->getName());
1826 llvm::ErrorOr<vfs::Status> S = FS.status(PathStr);
1831 // Skip entries which do not map to a reliable external content.
1832 if (FS.ignoreNonExistentContents() &&
1833 S.getError() == llvm::errc::no_such_file_or_directory) {
1843 std::error_code VFSFromYamlDirIterImpl::increment() {
1844 assert(Current != End && "cannot iterate past end");
1845 while (++Current != End) {
1846 SmallString<128> PathStr(Dir);
1847 llvm::sys::path::append(PathStr, (*Current)->getName());
1848 llvm::ErrorOr<vfs::Status> S = FS.status(PathStr);
1850 // Skip entries which do not map to a reliable external content.
1851 if (FS.ignoreNonExistentContents() &&
1852 S.getError() == llvm::errc::no_such_file_or_directory) {
1855 return S.getError();
1863 CurrentEntry = Status();
1864 return std::error_code();
1867 vfs::recursive_directory_iterator::recursive_directory_iterator(FileSystem &FS_,
1869 std::error_code &EC)
1871 directory_iterator I = FS->dir_begin(Path, EC);
1872 if (!EC && I != directory_iterator()) {
1873 State = std::make_shared<IterState>();
1878 vfs::recursive_directory_iterator &
1879 recursive_directory_iterator::increment(std::error_code &EC) {
1880 assert(FS && State && !State->empty() && "incrementing past end");
1881 assert(State->top()->isStatusKnown() && "non-canonical end iterator");
1882 vfs::directory_iterator End;
1883 if (State->top()->isDirectory()) {
1884 vfs::directory_iterator I = FS->dir_begin(State->top()->getName(), EC);
1893 while (!State->empty() && State->top().increment(EC) == End)
1897 State.reset(); // end iterator