YQ Connector: support managed ClickHouse

Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.

1 files changed, 660 insertions, 0 deletions

diff --git a/contrib/libs/clang14/lib/Basic/FileManager.cpp b/contrib/libs/clang14/lib/Basic/FileManager.cpp
new file mode 100644
index 00000000000..f4cf27848d7
--- /dev/null
+++ b/contrib/libs/clang14/lib/Basic/FileManager.cpp
@@ -0,0 +1,660 @@
+//===--- FileManager.cpp - File System Probing and Caching ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements the FileManager interface.
+//
+//===----------------------------------------------------------------------===//
+//
+// TODO: This should index all interesting directories with dirent calls.
+//  getdirentries ?
+//  opendir/readdir_r/closedir ?
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/FileSystemStatCache.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Config/llvm-config.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <cstdint>
+#include <cstdlib>
+#include <string>
+#include <utility>
+
+using namespace clang;
+
+#define DEBUG_TYPE "file-search"
+
+ALWAYS_ENABLED_STATISTIC(NumDirLookups, "Number of directory lookups.");
+ALWAYS_ENABLED_STATISTIC(NumFileLookups, "Number of file lookups.");
+ALWAYS_ENABLED_STATISTIC(NumDirCacheMisses,
+                         "Number of directory cache misses.");
+ALWAYS_ENABLED_STATISTIC(NumFileCacheMisses, "Number of file cache misses.");
+
+//===----------------------------------------------------------------------===//
+// Common logic.
+//===----------------------------------------------------------------------===//
+
+FileManager::FileManager(const FileSystemOptions &FSO,
+                         IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS)
+    : FS(std::move(FS)), FileSystemOpts(FSO), SeenDirEntries(64),
+      SeenFileEntries(64), NextFileUID(0) {
+  // If the caller doesn't provide a virtual file system, just grab the real
+  // file system.
+  if (!this->FS)
+    this->FS = llvm::vfs::getRealFileSystem();
+}
+
+FileManager::~FileManager() = default;
+
+void FileManager::setStatCache(std::unique_ptr<FileSystemStatCache> statCache) {
+  assert(statCache && "No stat cache provided?");
+  StatCache = std::move(statCache);
+}
+
+void FileManager::clearStatCache() { StatCache.reset(); }
+
+/// Retrieve the directory that the given file name resides in.
+/// Filename can point to either a real file or a virtual file.
+static llvm::Expected<DirectoryEntryRef>
+getDirectoryFromFile(FileManager &FileMgr, StringRef Filename,
+                     bool CacheFailure) {
+  if (Filename.empty())
+    return llvm::errorCodeToError(
+        make_error_code(std::errc::no_such_file_or_directory));
+
+  if (llvm::sys::path::is_separator(Filename[Filename.size() - 1]))
+    return llvm::errorCodeToError(make_error_code(std::errc::is_a_directory));
+
+  StringRef DirName = llvm::sys::path::parent_path(Filename);
+  // Use the current directory if file has no path component.
+  if (DirName.empty())
+    DirName = ".";
+
+  return FileMgr.getDirectoryRef(DirName, CacheFailure);
+}
+
+/// Add all ancestors of the given path (pointing to either a file or
+/// a directory) as virtual directories.
+void FileManager::addAncestorsAsVirtualDirs(StringRef Path) {
+  StringRef DirName = llvm::sys::path::parent_path(Path);
+  if (DirName.empty())
+    DirName = ".";
+
+  auto &NamedDirEnt = *SeenDirEntries.insert(
+        {DirName, std::errc::no_such_file_or_directory}).first;
+
+  // When caching a virtual directory, we always cache its ancestors
+  // at the same time.  Therefore, if DirName is already in the cache,
+  // we don't need to recurse as its ancestors must also already be in
+  // the cache (or it's a known non-virtual directory).
+  if (NamedDirEnt.second)
+    return;
+
+  // Add the virtual directory to the cache.
+  auto UDE = std::make_unique<DirectoryEntry>();
+  UDE->Name = NamedDirEnt.first();
+  NamedDirEnt.second = *UDE.get();
+  VirtualDirectoryEntries.push_back(std::move(UDE));
+
+  // Recursively add the other ancestors.
+  addAncestorsAsVirtualDirs(DirName);
+}
+
+llvm::Expected<DirectoryEntryRef>
+FileManager::getDirectoryRef(StringRef DirName, bool CacheFailure) {
+  // stat doesn't like trailing separators except for root directory.
+  // At least, on Win32 MSVCRT, stat() cannot strip trailing '/'.
+  // (though it can strip '\\')
+  if (DirName.size() > 1 &&
+      DirName != llvm::sys::path::root_path(DirName) &&
+      llvm::sys::path::is_separator(DirName.back()))
+    DirName = DirName.substr(0, DirName.size()-1);
+  Optional<std::string> DirNameStr;
+  if (is_style_windows(llvm::sys::path::Style::native)) {
+    // Fixing a problem with "clang C:test.c" on Windows.
+    // Stat("C:") does not recognize "C:" as a valid directory
+    if (DirName.size() > 1 && DirName.back() == ':' &&
+        DirName.equals_insensitive(llvm::sys::path::root_name(DirName))) {
+      DirNameStr = DirName.str() + '.';
+      DirName = *DirNameStr;
+    }
+  }
+
+  ++NumDirLookups;
+
+  // See if there was already an entry in the map.  Note that the map
+  // contains both virtual and real directories.
+  auto SeenDirInsertResult =
+      SeenDirEntries.insert({DirName, std::errc::no_such_file_or_directory});
+  if (!SeenDirInsertResult.second) {
+    if (SeenDirInsertResult.first->second)
+      return DirectoryEntryRef(*SeenDirInsertResult.first);
+    return llvm::errorCodeToError(SeenDirInsertResult.first->second.getError());
+  }
+
+  // We've not seen this before. Fill it in.
+  ++NumDirCacheMisses;
+  auto &NamedDirEnt = *SeenDirInsertResult.first;
+  assert(!NamedDirEnt.second && "should be newly-created");
+
+  // Get the null-terminated directory name as stored as the key of the
+  // SeenDirEntries map.
+  StringRef InterndDirName = NamedDirEnt.first();
+
+  // Check to see if the directory exists.
+  llvm::vfs::Status Status;
+  auto statError = getStatValue(InterndDirName, Status, false,
+                                nullptr /*directory lookup*/);
+  if (statError) {
+    // There's no real directory at the given path.
+    if (CacheFailure)
+      NamedDirEnt.second = statError;
+    else
+      SeenDirEntries.erase(DirName);
+    return llvm::errorCodeToError(statError);
+  }
+
+  // It exists.  See if we have already opened a directory with the
+  // same inode (this occurs on Unix-like systems when one dir is
+  // symlinked to another, for example) or the same path (on
+  // Windows).
+  DirectoryEntry &UDE = UniqueRealDirs[Status.getUniqueID()];
+
+  NamedDirEnt.second = UDE;
+  if (UDE.getName().empty()) {
+    // We don't have this directory yet, add it.  We use the string
+    // key from the SeenDirEntries map as the string.
+    UDE.Name  = InterndDirName;
+  }
+
+  return DirectoryEntryRef(NamedDirEnt);
+}
+
+llvm::ErrorOr<const DirectoryEntry *>
+FileManager::getDirectory(StringRef DirName, bool CacheFailure) {
+  auto Result = getDirectoryRef(DirName, CacheFailure);
+  if (Result)
+    return &Result->getDirEntry();
+  return llvm::errorToErrorCode(Result.takeError());
+}
+
+llvm::ErrorOr<const FileEntry *>
+FileManager::getFile(StringRef Filename, bool openFile, bool CacheFailure) {
+  auto Result = getFileRef(Filename, openFile, CacheFailure);
+  if (Result)
+    return &Result->getFileEntry();
+  return llvm::errorToErrorCode(Result.takeError());
+}
+
+llvm::Expected<FileEntryRef>
+FileManager::getFileRef(StringRef Filename, bool openFile, bool CacheFailure) {
+  ++NumFileLookups;
+
+  // See if there is already an entry in the map.
+  auto SeenFileInsertResult =
+      SeenFileEntries.insert({Filename, std::errc::no_such_file_or_directory});
+  if (!SeenFileInsertResult.second) {
+    if (!SeenFileInsertResult.first->second)
+      return llvm::errorCodeToError(
+          SeenFileInsertResult.first->second.getError());
+    // Construct and return and FileEntryRef, unless it's a redirect to another
+    // filename.
+    FileEntryRef::MapValue Value = *SeenFileInsertResult.first->second;
+    if (LLVM_LIKELY(Value.V.is<FileEntry *>()))
+      return FileEntryRef(*SeenFileInsertResult.first);
+    return FileEntryRef(*reinterpret_cast<const FileEntryRef::MapEntry *>(
+        Value.V.get<const void *>()));
+  }
+
+  // We've not seen this before. Fill it in.
+  ++NumFileCacheMisses;
+  auto *NamedFileEnt = &*SeenFileInsertResult.first;
+  assert(!NamedFileEnt->second && "should be newly-created");
+
+  // Get the null-terminated file name as stored as the key of the
+  // SeenFileEntries map.
+  StringRef InterndFileName = NamedFileEnt->first();
+
+  // Look up the directory for the file.  When looking up something like
+  // sys/foo.h we'll discover all of the search directories that have a 'sys'
+  // subdirectory.  This will let us avoid having to waste time on known-to-fail
+  // searches when we go to find sys/bar.h, because all the search directories
+  // without a 'sys' subdir will get a cached failure result.
+  auto DirInfoOrErr = getDirectoryFromFile(*this, Filename, CacheFailure);
+  if (!DirInfoOrErr) { // Directory doesn't exist, file can't exist.
+    std::error_code Err = errorToErrorCode(DirInfoOrErr.takeError());
+    if (CacheFailure)
+      NamedFileEnt->second = Err;
+    else
+      SeenFileEntries.erase(Filename);
+
+    return llvm::errorCodeToError(Err);
+  }
+  DirectoryEntryRef DirInfo = *DirInfoOrErr;
+
+  // FIXME: Use the directory info to prune this, before doing the stat syscall.
+  // FIXME: This will reduce the # syscalls.
+
+  // Check to see if the file exists.
+  std::unique_ptr<llvm::vfs::File> F;
+  llvm::vfs::Status Status;
+  auto statError = getStatValue(InterndFileName, Status, true,
+                                openFile ? &F : nullptr);
+  if (statError) {
+    // There's no real file at the given path.
+    if (CacheFailure)
+      NamedFileEnt->second = statError;
+    else
+      SeenFileEntries.erase(Filename);
+
+    return llvm::errorCodeToError(statError);
+  }
+
+  assert((openFile || !F) && "undesired open file");
+
+  // It exists.  See if we have already opened a file with the same inode.
+  // This occurs when one dir is symlinked to another, for example.
+  FileEntry &UFE = UniqueRealFiles[Status.getUniqueID()];
+
+  if (Status.getName() == Filename) {
+    // The name matches. Set the FileEntry.
+    NamedFileEnt->second = FileEntryRef::MapValue(UFE, DirInfo);
+  } else {
+    // Name mismatch. We need a redirect. First grab the actual entry we want
+    // to return.
+    //
+    // This redirection logic intentionally leaks the external name of a
+    // redirected file that uses 'use-external-name' in \a
+    // vfs::RedirectionFileSystem. This allows clang to report the external
+    // name to users (in diagnostics) and to tools that don't have access to
+    // the VFS (in debug info and dependency '.d' files).
+    //
+    // FIXME: This is pretty complicated. It's also inconsistent with how
+    // "real" filesystems behave and confuses parts of clang expect to see the
+    // name-as-accessed on the \a FileEntryRef. Maybe the returned \a
+    // FileEntryRef::getName() could return the accessed name unmodified, but
+    // make the external name available via a separate API.
+    auto &Redirection =
+        *SeenFileEntries
+             .insert({Status.getName(), FileEntryRef::MapValue(UFE, DirInfo)})
+             .first;
+    assert(Redirection.second->V.is<FileEntry *>() &&
+           "filename redirected to a non-canonical filename?");
+    assert(Redirection.second->V.get<FileEntry *>() == &UFE &&
+           "filename from getStatValue() refers to wrong file");
+
+    // Cache the redirection in the previously-inserted entry, still available
+    // in the tentative return value.
+    NamedFileEnt->second = FileEntryRef::MapValue(Redirection);
+
+    // Fix the tentative return value.
+    NamedFileEnt = &Redirection;
+  }
+
+  FileEntryRef ReturnedRef(*NamedFileEnt);
+  if (UFE.isValid()) { // Already have an entry with this inode, return it.
+
+    // FIXME: this hack ensures that if we look up a file by a virtual path in
+    // the VFS that the getDir() will have the virtual path, even if we found
+    // the file by a 'real' path first. This is required in order to find a
+    // module's structure when its headers/module map are mapped in the VFS.
+    // We should remove this as soon as we can properly support a file having
+    // multiple names.
+    if (&DirInfo.getDirEntry() != UFE.Dir && Status.IsVFSMapped)
+      UFE.Dir = &DirInfo.getDirEntry();
+
+    // Always update LastRef to the last name by which a file was accessed.
+    // FIXME: Neither this nor always using the first reference is correct; we
+    // want to switch towards a design where we return a FileName object that
+    // encapsulates both the name by which the file was accessed and the
+    // corresponding FileEntry.
+    // FIXME: LastRef should be removed from FileEntry once all clients adopt
+    // FileEntryRef.
+    UFE.LastRef = ReturnedRef;
+
+    return ReturnedRef;
+  }
+
+  // Otherwise, we don't have this file yet, add it.
+  UFE.LastRef = ReturnedRef;
+  UFE.Size    = Status.getSize();
+  UFE.ModTime = llvm::sys::toTimeT(Status.getLastModificationTime());
+  UFE.Dir     = &DirInfo.getDirEntry();
+  UFE.UID     = NextFileUID++;
+  UFE.UniqueID = Status.getUniqueID();
+  UFE.IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file;
+  UFE.File = std::move(F);
+  UFE.IsValid = true;
+
+  if (UFE.File) {
+    if (auto PathName = UFE.File->getName())
+      fillRealPathName(&UFE, *PathName);
+  } else if (!openFile) {
+    // We should still fill the path even if we aren't opening the file.
+    fillRealPathName(&UFE, InterndFileName);
+  }
+  return ReturnedRef;
+}
+
+llvm::Expected<FileEntryRef> FileManager::getSTDIN() {
+  // Only read stdin once.
+  if (STDIN)
+    return *STDIN;
+
+  std::unique_ptr<llvm::MemoryBuffer> Content;
+  if (auto ContentOrError = llvm::MemoryBuffer::getSTDIN())
+    Content = std::move(*ContentOrError);
+  else
+    return llvm::errorCodeToError(ContentOrError.getError());
+
+  STDIN = getVirtualFileRef(Content->getBufferIdentifier(),
+                            Content->getBufferSize(), 0);
+  FileEntry &FE = const_cast<FileEntry &>(STDIN->getFileEntry());
+  FE.Content = std::move(Content);
+  FE.IsNamedPipe = true;
+  return *STDIN;
+}
+
+const FileEntry *FileManager::getVirtualFile(StringRef Filename, off_t Size,
+                                             time_t ModificationTime) {
+  return &getVirtualFileRef(Filename, Size, ModificationTime).getFileEntry();
+}
+
+FileEntryRef FileManager::getVirtualFileRef(StringRef Filename, off_t Size,
+                                            time_t ModificationTime) {
+  ++NumFileLookups;
+
+  // See if there is already an entry in the map for an existing file.
+  auto &NamedFileEnt = *SeenFileEntries.insert(
+      {Filename, std::errc::no_such_file_or_directory}).first;
+  if (NamedFileEnt.second) {
+    FileEntryRef::MapValue Value = *NamedFileEnt.second;
+    if (LLVM_LIKELY(Value.V.is<FileEntry *>()))
+      return FileEntryRef(NamedFileEnt);
+    return FileEntryRef(*reinterpret_cast<const FileEntryRef::MapEntry *>(
+        Value.V.get<const void *>()));
+  }
+
+  // We've not seen this before, or the file is cached as non-existent.
+  ++NumFileCacheMisses;
+  addAncestorsAsVirtualDirs(Filename);
+  FileEntry *UFE = nullptr;
+
+  // Now that all ancestors of Filename are in the cache, the
+  // following call is guaranteed to find the DirectoryEntry from the
+  // cache. A virtual file can also have an empty filename, that could come
+  // from a source location preprocessor directive with an empty filename as
+  // an example, so we need to pretend it has a name to ensure a valid directory
+  // entry can be returned.
+  auto DirInfo = expectedToOptional(getDirectoryFromFile(
+      *this, Filename.empty() ? "." : Filename, /*CacheFailure=*/true));
+  assert(DirInfo &&
+         "The directory of a virtual file should already be in the cache.");
+
+  // Check to see if the file exists. If so, drop the virtual file
+  llvm::vfs::Status Status;
+  const char *InterndFileName = NamedFileEnt.first().data();
+  if (!getStatValue(InterndFileName, Status, true, nullptr)) {
+    UFE = &UniqueRealFiles[Status.getUniqueID()];
+    Status = llvm::vfs::Status(
+      Status.getName(), Status.getUniqueID(),
+      llvm::sys::toTimePoint(ModificationTime),
+      Status.getUser(), Status.getGroup(), Size,
+      Status.getType(), Status.getPermissions());
+
+    NamedFileEnt.second = FileEntryRef::MapValue(*UFE, *DirInfo);
+
+    // If we had already opened this file, close it now so we don't
+    // leak the descriptor. We're not going to use the file
+    // descriptor anyway, since this is a virtual file.
+    if (UFE->File)
+      UFE->closeFile();
+
+    // If we already have an entry with this inode, return it.
+    //
+    // FIXME: Surely this should add a reference by the new name, and return
+    // it instead...
+    if (UFE->isValid())
+      return FileEntryRef(NamedFileEnt);
+
+    UFE->UniqueID = Status.getUniqueID();
+    UFE->IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file;
+    fillRealPathName(UFE, Status.getName());
+  } else {
+    VirtualFileEntries.push_back(std::make_unique<FileEntry>());
+    UFE = VirtualFileEntries.back().get();
+    NamedFileEnt.second = FileEntryRef::MapValue(*UFE, *DirInfo);
+  }
+
+  UFE->LastRef = FileEntryRef(NamedFileEnt);
+  UFE->Size    = Size;
+  UFE->ModTime = ModificationTime;
+  UFE->Dir     = &DirInfo->getDirEntry();
+  UFE->UID     = NextFileUID++;
+  UFE->IsValid = true;
+  UFE->File.reset();
+  return FileEntryRef(NamedFileEnt);
+}
+
+llvm::Optional<FileEntryRef> FileManager::getBypassFile(FileEntryRef VF) {
+  // Stat of the file and return nullptr if it doesn't exist.
+  llvm::vfs::Status Status;
+  if (getStatValue(VF.getName(), Status, /*isFile=*/true, /*F=*/nullptr))
+    return None;
+
+  if (!SeenBypassFileEntries)
+    SeenBypassFileEntries = std::make_unique<
+        llvm::StringMap<llvm::ErrorOr<FileEntryRef::MapValue>>>();
+
+  // If we've already bypassed just use the existing one.
+  auto Insertion = SeenBypassFileEntries->insert(
+      {VF.getName(), std::errc::no_such_file_or_directory});
+  if (!Insertion.second)
+    return FileEntryRef(*Insertion.first);
+
+  // Fill in the new entry from the stat.
+  BypassFileEntries.push_back(std::make_unique<FileEntry>());
+  const FileEntry &VFE = VF.getFileEntry();
+  FileEntry &BFE = *BypassFileEntries.back();
+  Insertion.first->second = FileEntryRef::MapValue(BFE, VF.getDir());
+  BFE.LastRef = FileEntryRef(*Insertion.first);
+  BFE.Size = Status.getSize();
+  BFE.Dir = VFE.Dir;
+  BFE.ModTime = llvm::sys::toTimeT(Status.getLastModificationTime());
+  BFE.UID = NextFileUID++;
+  BFE.IsValid = true;
+
+  // Save the entry in the bypass table and return.
+  return FileEntryRef(*Insertion.first);
+}
+
+bool FileManager::FixupRelativePath(SmallVectorImpl<char> &path) const {
+  StringRef pathRef(path.data(), path.size());
+
+  if (FileSystemOpts.WorkingDir.empty()
+      || llvm::sys::path::is_absolute(pathRef))
+    return false;
+
+  SmallString<128> NewPath(FileSystemOpts.WorkingDir);
+  llvm::sys::path::append(NewPath, pathRef);
+  path = NewPath;
+  return true;
+}
+
+bool FileManager::makeAbsolutePath(SmallVectorImpl<char> &Path) const {
+  bool Changed = FixupRelativePath(Path);
+
+  if (!llvm::sys::path::is_absolute(StringRef(Path.data(), Path.size()))) {
+    FS->makeAbsolute(Path);
+    Changed = true;
+  }
+
+  return Changed;
+}
+
+void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
+  llvm::SmallString<128> AbsPath(FileName);
+  // This is not the same as `VFS::getRealPath()`, which resolves symlinks
+  // but can be very expensive on real file systems.
+  // FIXME: the semantic of RealPathName is unclear, and the name might be
+  // misleading. We need to clean up the interface here.
+  makeAbsolutePath(AbsPath);
+  llvm::sys::path::remove_dots(AbsPath, /*remove_dot_dot=*/true);
+  UFE->RealPathName = std::string(AbsPath.str());
+}
+
+llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
+FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
+                              bool RequiresNullTerminator) {
+  // If the content is living on the file entry, return a reference to it.
+  if (Entry->Content)
+    return llvm::MemoryBuffer::getMemBuffer(Entry->Content->getMemBufferRef());
+
+  uint64_t FileSize = Entry->getSize();
+  // If there's a high enough chance that the file have changed since we
+  // got its size, force a stat before opening it.
+  if (isVolatile || Entry->isNamedPipe())
+    FileSize = -1;
+
+  StringRef Filename = Entry->getName();
+  // If the file is already open, use the open file descriptor.
+  if (Entry->File) {
+    auto Result = Entry->File->getBuffer(Filename, FileSize,
+                                         RequiresNullTerminator, isVolatile);
+    Entry->closeFile();
+    return Result;
+  }
+
+  // Otherwise, open the file.
+  return getBufferForFileImpl(Filename, FileSize, isVolatile,
+                              RequiresNullTerminator);
+}
+
+llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
+FileManager::getBufferForFileImpl(StringRef Filename, int64_t FileSize,
+                                  bool isVolatile,
+                                  bool RequiresNullTerminator) {
+  if (FileSystemOpts.WorkingDir.empty())
+    return FS->getBufferForFile(Filename, FileSize, RequiresNullTerminator,
+                                isVolatile);
+
+  SmallString<128> FilePath(Filename);
+  FixupRelativePath(FilePath);
+  return FS->getBufferForFile(FilePath, FileSize, RequiresNullTerminator,
+                              isVolatile);
+}
+
+/// getStatValue - Get the 'stat' information for the specified path,
+/// using the cache to accelerate it if possible.  This returns true
+/// if the path points to a virtual file or does not exist, or returns
+/// false if it's an existent real file.  If FileDescriptor is NULL,
+/// do directory look-up instead of file look-up.
+std::error_code
+FileManager::getStatValue(StringRef Path, llvm::vfs::Status &Status,
+                          bool isFile, std::unique_ptr<llvm::vfs::File> *F) {
+  // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
+  // absolute!
+  if (FileSystemOpts.WorkingDir.empty())
+    return FileSystemStatCache::get(Path, Status, isFile, F,
+                                    StatCache.get(), *FS);
+
+  SmallString<128> FilePath(Path);
+  FixupRelativePath(FilePath);
+
+  return FileSystemStatCache::get(FilePath.c_str(), Status, isFile, F,
+                                  StatCache.get(), *FS);
+}
+
+std::error_code
+FileManager::getNoncachedStatValue(StringRef Path,
+                                   llvm::vfs::Status &Result) {
+  SmallString<128> FilePath(Path);
+  FixupRelativePath(FilePath);
+
+  llvm::ErrorOr<llvm::vfs::Status> S = FS->status(FilePath.c_str());
+  if (!S)
+    return S.getError();
+  Result = *S;
+  return std::error_code();
+}
+
+void FileManager::GetUniqueIDMapping(
+                   SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
+  UIDToFiles.clear();
+  UIDToFiles.resize(NextFileUID);
+
+  // Map file entries
+  for (llvm::StringMap<llvm::ErrorOr<FileEntryRef::MapValue>,
+                       llvm::BumpPtrAllocator>::const_iterator
+           FE = SeenFileEntries.begin(),
+           FEEnd = SeenFileEntries.end();
+       FE != FEEnd; ++FE)
+    if (llvm::ErrorOr<FileEntryRef::MapValue> Entry = FE->getValue()) {
+      if (const auto *FE = Entry->V.dyn_cast<FileEntry *>())
+        UIDToFiles[FE->getUID()] = FE;
+    }
+
+  // Map virtual file entries
+  for (const auto &VFE : VirtualFileEntries)
+    UIDToFiles[VFE->getUID()] = VFE.get();
+}
+
+StringRef FileManager::getCanonicalName(const DirectoryEntry *Dir) {
+  llvm::DenseMap<const void *, llvm::StringRef>::iterator Known
+    = CanonicalNames.find(Dir);
+  if (Known != CanonicalNames.end())
+    return Known->second;
+
+  StringRef CanonicalName(Dir->getName());
+
+  SmallString<4096> CanonicalNameBuf;
+  if (!FS->getRealPath(Dir->getName(), CanonicalNameBuf))
+    CanonicalName = CanonicalNameBuf.str().copy(CanonicalNameStorage);
+
+  CanonicalNames.insert({Dir, CanonicalName});
+  return CanonicalName;
+}
+
+StringRef FileManager::getCanonicalName(const FileEntry *File) {
+  llvm::DenseMap<const void *, llvm::StringRef>::iterator Known
+    = CanonicalNames.find(File);
+  if (Known != CanonicalNames.end())
+    return Known->second;
+
+  StringRef CanonicalName(File->getName());
+
+  SmallString<4096> CanonicalNameBuf;
+  if (!FS->getRealPath(File->getName(), CanonicalNameBuf))
+    CanonicalName = CanonicalNameBuf.str().copy(CanonicalNameStorage);
+
+  CanonicalNames.insert({File, CanonicalName});
+  return CanonicalName;
+}
+
+void FileManager::PrintStats() const {
+  llvm::errs() << "\n*** File Manager Stats:\n";
+  llvm::errs() << UniqueRealFiles.size() << " real files found, "
+               << UniqueRealDirs.size() << " real dirs found.\n";
+  llvm::errs() << VirtualFileEntries.size() << " virtual files found, "
+               << VirtualDirectoryEntries.size() << " virtual dirs found.\n";
+  llvm::errs() << NumDirLookups << " dir lookups, "
+               << NumDirCacheMisses << " dir cache misses.\n";
+  llvm::errs() << NumFileLookups << " file lookups, "
+               << NumFileCacheMisses << " file cache misses.\n";
+
+  //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;
+}