clang  8.0.0
FileManager.cpp
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1 //===--- FileManager.cpp - File System Probing and Caching ----------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the FileManager interface.
11 //
12 //===----------------------------------------------------------------------===//
13 //
14 // TODO: This should index all interesting directories with dirent calls.
15 // getdirentries ?
16 // opendir/readdir_r/closedir ?
17 //
18 //===----------------------------------------------------------------------===//
19 
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/Config/llvm-config.h"
24 #include "llvm/ADT/STLExtras.h"
25 #include "llvm/Support/FileSystem.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/Path.h"
28 #include "llvm/Support/raw_ostream.h"
29 #include <algorithm>
30 #include <cassert>
31 #include <climits>
32 #include <cstdint>
33 #include <cstdlib>
34 #include <string>
35 #include <utility>
36 
37 using namespace clang;
38 
39 /// NON_EXISTENT_DIR - A special value distinct from null that is used to
40 /// represent a dir name that doesn't exist on the disk.
41 #define NON_EXISTENT_DIR reinterpret_cast<DirectoryEntry*>((intptr_t)-1)
42 
43 /// NON_EXISTENT_FILE - A special value distinct from null that is used to
44 /// represent a filename that doesn't exist on the disk.
45 #define NON_EXISTENT_FILE reinterpret_cast<FileEntry*>((intptr_t)-1)
46 
47 //===----------------------------------------------------------------------===//
48 // Common logic.
49 //===----------------------------------------------------------------------===//
50 
53  : FS(std::move(FS)), FileSystemOpts(FSO), SeenDirEntries(64),
54  SeenFileEntries(64), NextFileUID(0) {
55  NumDirLookups = NumFileLookups = 0;
56  NumDirCacheMisses = NumFileCacheMisses = 0;
57 
58  // If the caller doesn't provide a virtual file system, just grab the real
59  // file system.
60  if (!this->FS)
61  this->FS = llvm::vfs::getRealFileSystem();
62 }
63 
64 FileManager::~FileManager() = default;
65 
66 void FileManager::setStatCache(std::unique_ptr<FileSystemStatCache> statCache) {
67  assert(statCache && "No stat cache provided?");
68  StatCache = std::move(statCache);
69 }
70 
71 void FileManager::clearStatCache() { StatCache.reset(); }
72 
73 /// Retrieve the directory that the given file name resides in.
74 /// Filename can point to either a real file or a virtual file.
76  StringRef Filename,
77  bool CacheFailure) {
78  if (Filename.empty())
79  return nullptr;
80 
81  if (llvm::sys::path::is_separator(Filename[Filename.size() - 1]))
82  return nullptr; // If Filename is a directory.
83 
84  StringRef DirName = llvm::sys::path::parent_path(Filename);
85  // Use the current directory if file has no path component.
86  if (DirName.empty())
87  DirName = ".";
88 
89  return FileMgr.getDirectory(DirName, CacheFailure);
90 }
91 
92 /// Add all ancestors of the given path (pointing to either a file or
93 /// a directory) as virtual directories.
94 void FileManager::addAncestorsAsVirtualDirs(StringRef Path) {
95  StringRef DirName = llvm::sys::path::parent_path(Path);
96  if (DirName.empty())
97  DirName = ".";
98 
99  auto &NamedDirEnt =
100  *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
101 
102  // When caching a virtual directory, we always cache its ancestors
103  // at the same time. Therefore, if DirName is already in the cache,
104  // we don't need to recurse as its ancestors must also already be in
105  // the cache.
106  if (NamedDirEnt.second && NamedDirEnt.second != NON_EXISTENT_DIR)
107  return;
108 
109  // Add the virtual directory to the cache.
110  auto UDE = llvm::make_unique<DirectoryEntry>();
111  UDE->Name = NamedDirEnt.first();
112  NamedDirEnt.second = UDE.get();
113  VirtualDirectoryEntries.push_back(std::move(UDE));
114 
115  // Recursively add the other ancestors.
116  addAncestorsAsVirtualDirs(DirName);
117 }
118 
119 const DirectoryEntry *FileManager::getDirectory(StringRef DirName,
120  bool CacheFailure) {
121  // stat doesn't like trailing separators except for root directory.
122  // At least, on Win32 MSVCRT, stat() cannot strip trailing '/'.
123  // (though it can strip '\\')
124  if (DirName.size() > 1 &&
125  DirName != llvm::sys::path::root_path(DirName) &&
126  llvm::sys::path::is_separator(DirName.back()))
127  DirName = DirName.substr(0, DirName.size()-1);
128 #ifdef _WIN32
129  // Fixing a problem with "clang C:test.c" on Windows.
130  // Stat("C:") does not recognize "C:" as a valid directory
131  std::string DirNameStr;
132  if (DirName.size() > 1 && DirName.back() == ':' &&
133  DirName.equals_lower(llvm::sys::path::root_name(DirName))) {
134  DirNameStr = DirName.str() + '.';
135  DirName = DirNameStr;
136  }
137 #endif
138 
139  ++NumDirLookups;
140  auto &NamedDirEnt =
141  *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
142 
143  // See if there was already an entry in the map. Note that the map
144  // contains both virtual and real directories.
145  if (NamedDirEnt.second)
146  return NamedDirEnt.second == NON_EXISTENT_DIR ? nullptr
147  : NamedDirEnt.second;
148 
149  ++NumDirCacheMisses;
150 
151  // By default, initialize it to invalid.
152  NamedDirEnt.second = NON_EXISTENT_DIR;
153 
154  // Get the null-terminated directory name as stored as the key of the
155  // SeenDirEntries map.
156  StringRef InterndDirName = NamedDirEnt.first();
157 
158  // Check to see if the directory exists.
159  FileData Data;
160  if (getStatValue(InterndDirName, Data, false, nullptr /*directory lookup*/)) {
161  // There's no real directory at the given path.
162  if (!CacheFailure)
163  SeenDirEntries.erase(DirName);
164  return nullptr;
165  }
166 
167  // It exists. See if we have already opened a directory with the
168  // same inode (this occurs on Unix-like systems when one dir is
169  // symlinked to another, for example) or the same path (on
170  // Windows).
171  DirectoryEntry &UDE = UniqueRealDirs[Data.UniqueID];
172 
173  NamedDirEnt.second = &UDE;
174  if (UDE.getName().empty()) {
175  // We don't have this directory yet, add it. We use the string
176  // key from the SeenDirEntries map as the string.
177  UDE.Name = InterndDirName;
178  }
179 
180  return &UDE;
181 }
182 
183 const FileEntry *FileManager::getFile(StringRef Filename, bool openFile,
184  bool CacheFailure) {
185  ++NumFileLookups;
186 
187  // See if there is already an entry in the map.
188  auto &NamedFileEnt =
189  *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
190 
191  // See if there is already an entry in the map.
192  if (NamedFileEnt.second)
193  return NamedFileEnt.second == NON_EXISTENT_FILE ? nullptr
194  : NamedFileEnt.second;
195 
196  ++NumFileCacheMisses;
197 
198  // By default, initialize it to invalid.
199  NamedFileEnt.second = NON_EXISTENT_FILE;
200 
201  // Get the null-terminated file name as stored as the key of the
202  // SeenFileEntries map.
203  StringRef InterndFileName = NamedFileEnt.first();
204 
205  // Look up the directory for the file. When looking up something like
206  // sys/foo.h we'll discover all of the search directories that have a 'sys'
207  // subdirectory. This will let us avoid having to waste time on known-to-fail
208  // searches when we go to find sys/bar.h, because all the search directories
209  // without a 'sys' subdir will get a cached failure result.
210  const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
211  CacheFailure);
212  if (DirInfo == nullptr) { // Directory doesn't exist, file can't exist.
213  if (!CacheFailure)
214  SeenFileEntries.erase(Filename);
215 
216  return nullptr;
217  }
218 
219  // FIXME: Use the directory info to prune this, before doing the stat syscall.
220  // FIXME: This will reduce the # syscalls.
221 
222  // Nope, there isn't. Check to see if the file exists.
223  std::unique_ptr<llvm::vfs::File> F;
224  FileData Data;
225  if (getStatValue(InterndFileName, Data, true, openFile ? &F : nullptr)) {
226  // There's no real file at the given path.
227  if (!CacheFailure)
228  SeenFileEntries.erase(Filename);
229 
230  return nullptr;
231  }
232 
233  assert((openFile || !F) && "undesired open file");
234 
235  // It exists. See if we have already opened a file with the same inode.
236  // This occurs when one dir is symlinked to another, for example.
237  FileEntry &UFE = UniqueRealFiles[Data.UniqueID];
238 
239  NamedFileEnt.second = &UFE;
240 
241  // If the name returned by getStatValue is different than Filename, re-intern
242  // the name.
243  if (Data.Name != Filename) {
244  auto &NamedFileEnt =
245  *SeenFileEntries.insert(std::make_pair(Data.Name, nullptr)).first;
246  if (!NamedFileEnt.second)
247  NamedFileEnt.second = &UFE;
248  else
249  assert(NamedFileEnt.second == &UFE &&
250  "filename from getStatValue() refers to wrong file");
251  InterndFileName = NamedFileEnt.first().data();
252  }
253 
254  if (UFE.isValid()) { // Already have an entry with this inode, return it.
255 
256  // FIXME: this hack ensures that if we look up a file by a virtual path in
257  // the VFS that the getDir() will have the virtual path, even if we found
258  // the file by a 'real' path first. This is required in order to find a
259  // module's structure when its headers/module map are mapped in the VFS.
260  // We should remove this as soon as we can properly support a file having
261  // multiple names.
262  if (DirInfo != UFE.Dir && Data.IsVFSMapped)
263  UFE.Dir = DirInfo;
264 
265  // Always update the name to use the last name by which a file was accessed.
266  // FIXME: Neither this nor always using the first name is correct; we want
267  // to switch towards a design where we return a FileName object that
268  // encapsulates both the name by which the file was accessed and the
269  // corresponding FileEntry.
270  UFE.Name = InterndFileName;
271 
272  return &UFE;
273  }
274 
275  // Otherwise, we don't have this file yet, add it.
276  UFE.Name = InterndFileName;
277  UFE.Size = Data.Size;
278  UFE.ModTime = Data.ModTime;
279  UFE.Dir = DirInfo;
280  UFE.UID = NextFileUID++;
281  UFE.UniqueID = Data.UniqueID;
282  UFE.IsNamedPipe = Data.IsNamedPipe;
283  UFE.InPCH = Data.InPCH;
284  UFE.File = std::move(F);
285  UFE.IsValid = true;
286 
287  if (UFE.File) {
288  if (auto PathName = UFE.File->getName())
289  fillRealPathName(&UFE, *PathName);
290  }
291  return &UFE;
292 }
293 
294 const FileEntry *
295 FileManager::getVirtualFile(StringRef Filename, off_t Size,
296  time_t ModificationTime) {
297  ++NumFileLookups;
298 
299  // See if there is already an entry in the map.
300  auto &NamedFileEnt =
301  *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
302 
303  // See if there is already an entry in the map.
304  if (NamedFileEnt.second && NamedFileEnt.second != NON_EXISTENT_FILE)
305  return NamedFileEnt.second;
306 
307  ++NumFileCacheMisses;
308 
309  // By default, initialize it to invalid.
310  NamedFileEnt.second = NON_EXISTENT_FILE;
311 
312  addAncestorsAsVirtualDirs(Filename);
313  FileEntry *UFE = nullptr;
314 
315  // Now that all ancestors of Filename are in the cache, the
316  // following call is guaranteed to find the DirectoryEntry from the
317  // cache.
318  const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
319  /*CacheFailure=*/true);
320  assert(DirInfo &&
321  "The directory of a virtual file should already be in the cache.");
322 
323  // Check to see if the file exists. If so, drop the virtual file
324  FileData Data;
325  const char *InterndFileName = NamedFileEnt.first().data();
326  if (getStatValue(InterndFileName, Data, true, nullptr) == 0) {
327  Data.Size = Size;
328  Data.ModTime = ModificationTime;
329  UFE = &UniqueRealFiles[Data.UniqueID];
330 
331  NamedFileEnt.second = UFE;
332 
333  // If we had already opened this file, close it now so we don't
334  // leak the descriptor. We're not going to use the file
335  // descriptor anyway, since this is a virtual file.
336  if (UFE->File)
337  UFE->closeFile();
338 
339  // If we already have an entry with this inode, return it.
340  if (UFE->isValid())
341  return UFE;
342 
343  UFE->UniqueID = Data.UniqueID;
344  UFE->IsNamedPipe = Data.IsNamedPipe;
345  UFE->InPCH = Data.InPCH;
346  fillRealPathName(UFE, Data.Name);
347  }
348 
349  if (!UFE) {
350  VirtualFileEntries.push_back(llvm::make_unique<FileEntry>());
351  UFE = VirtualFileEntries.back().get();
352  NamedFileEnt.second = UFE;
353  }
354 
355  UFE->Name = InterndFileName;
356  UFE->Size = Size;
357  UFE->ModTime = ModificationTime;
358  UFE->Dir = DirInfo;
359  UFE->UID = NextFileUID++;
360  UFE->IsValid = true;
361  UFE->File.reset();
362  return UFE;
363 }
364 
366  StringRef pathRef(path.data(), path.size());
367 
368  if (FileSystemOpts.WorkingDir.empty()
369  || llvm::sys::path::is_absolute(pathRef))
370  return false;
371 
372  SmallString<128> NewPath(FileSystemOpts.WorkingDir);
373  llvm::sys::path::append(NewPath, pathRef);
374  path = NewPath;
375  return true;
376 }
377 
379  bool Changed = FixupRelativePath(Path);
380 
381  if (!llvm::sys::path::is_absolute(StringRef(Path.data(), Path.size()))) {
382  FS->makeAbsolute(Path);
383  Changed = true;
384  }
385 
386  return Changed;
387 }
388 
389 void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
390  llvm::SmallString<128> AbsPath(FileName);
391  // This is not the same as `VFS::getRealPath()`, which resolves symlinks
392  // but can be very expensive on real file systems.
393  // FIXME: the semantic of RealPathName is unclear, and the name might be
394  // misleading. We need to clean up the interface here.
395  makeAbsolutePath(AbsPath);
396  llvm::sys::path::remove_dots(AbsPath, /*remove_dot_dot=*/true);
397  UFE->RealPathName = AbsPath.str();
398 }
399 
400 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
401 FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
402  bool ShouldCloseOpenFile) {
403  uint64_t FileSize = Entry->getSize();
404  // If there's a high enough chance that the file have changed since we
405  // got its size, force a stat before opening it.
406  if (isVolatile)
407  FileSize = -1;
408 
409  StringRef Filename = Entry->getName();
410  // If the file is already open, use the open file descriptor.
411  if (Entry->File) {
412  auto Result =
413  Entry->File->getBuffer(Filename, FileSize,
414  /*RequiresNullTerminator=*/true, isVolatile);
415  // FIXME: we need a set of APIs that can make guarantees about whether a
416  // FileEntry is open or not.
417  if (ShouldCloseOpenFile)
418  Entry->closeFile();
419  return Result;
420  }
421 
422  // Otherwise, open the file.
423 
424  if (FileSystemOpts.WorkingDir.empty())
425  return FS->getBufferForFile(Filename, FileSize,
426  /*RequiresNullTerminator=*/true, isVolatile);
427 
428  SmallString<128> FilePath(Entry->getName());
429  FixupRelativePath(FilePath);
430  return FS->getBufferForFile(FilePath, FileSize,
431  /*RequiresNullTerminator=*/true, isVolatile);
432 }
433 
434 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
435 FileManager::getBufferForFile(StringRef Filename, bool isVolatile) {
436  if (FileSystemOpts.WorkingDir.empty())
437  return FS->getBufferForFile(Filename, -1, true, isVolatile);
438 
439  SmallString<128> FilePath(Filename);
440  FixupRelativePath(FilePath);
441  return FS->getBufferForFile(FilePath.c_str(), -1, true, isVolatile);
442 }
443 
444 /// getStatValue - Get the 'stat' information for the specified path,
445 /// using the cache to accelerate it if possible. This returns true
446 /// if the path points to a virtual file or does not exist, or returns
447 /// false if it's an existent real file. If FileDescriptor is NULL,
448 /// do directory look-up instead of file look-up.
449 bool FileManager::getStatValue(StringRef Path, FileData &Data, bool isFile,
450  std::unique_ptr<llvm::vfs::File> *F) {
451  // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
452  // absolute!
453  if (FileSystemOpts.WorkingDir.empty())
454  return FileSystemStatCache::get(Path, Data, isFile, F,StatCache.get(), *FS);
455 
456  SmallString<128> FilePath(Path);
457  FixupRelativePath(FilePath);
458 
459  return FileSystemStatCache::get(FilePath.c_str(), Data, isFile, F,
460  StatCache.get(), *FS);
461 }
462 
464  llvm::vfs::Status &Result) {
465  SmallString<128> FilePath(Path);
466  FixupRelativePath(FilePath);
467 
468  llvm::ErrorOr<llvm::vfs::Status> S = FS->status(FilePath.c_str());
469  if (!S)
470  return true;
471  Result = *S;
472  return false;
473 }
474 
476  assert(Entry && "Cannot invalidate a NULL FileEntry");
477 
478  SeenFileEntries.erase(Entry->getName());
479 
480  // FileEntry invalidation should not block future optimizations in the file
481  // caches. Possible alternatives are cache truncation (invalidate last N) or
482  // invalidation of the whole cache.
483  UniqueRealFiles.erase(Entry->getUniqueID());
484 }
485 
487  SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
488  UIDToFiles.clear();
489  UIDToFiles.resize(NextFileUID);
490 
491  // Map file entries
492  for (llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator>::const_iterator
493  FE = SeenFileEntries.begin(), FEEnd = SeenFileEntries.end();
494  FE != FEEnd; ++FE)
495  if (FE->getValue() && FE->getValue() != NON_EXISTENT_FILE)
496  UIDToFiles[FE->getValue()->getUID()] = FE->getValue();
497 
498  // Map virtual file entries
499  for (const auto &VFE : VirtualFileEntries)
500  if (VFE && VFE.get() != NON_EXISTENT_FILE)
501  UIDToFiles[VFE->getUID()] = VFE.get();
502 }
503 
505  off_t Size, time_t ModificationTime) {
506  File->Size = Size;
507  File->ModTime = ModificationTime;
508 }
509 
511  // FIXME: use llvm::sys::fs::canonical() when it gets implemented
512  llvm::DenseMap<const DirectoryEntry *, llvm::StringRef>::iterator Known
513  = CanonicalDirNames.find(Dir);
514  if (Known != CanonicalDirNames.end())
515  return Known->second;
516 
517  StringRef CanonicalName(Dir->getName());
518 
519  SmallString<4096> CanonicalNameBuf;
520  if (!FS->getRealPath(Dir->getName(), CanonicalNameBuf))
521  CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
522 
523  CanonicalDirNames.insert(std::make_pair(Dir, CanonicalName));
524  return CanonicalName;
525 }
526 
528  llvm::errs() << "\n*** File Manager Stats:\n";
529  llvm::errs() << UniqueRealFiles.size() << " real files found, "
530  << UniqueRealDirs.size() << " real dirs found.\n";
531  llvm::errs() << VirtualFileEntries.size() << " virtual files found, "
532  << VirtualDirectoryEntries.size() << " virtual dirs found.\n";
533  llvm::errs() << NumDirLookups << " dir lookups, "
534  << NumDirCacheMisses << " dir cache misses.\n";
535  llvm::errs() << NumFileLookups << " file lookups, "
536  << NumFileCacheMisses << " file cache misses.\n";
537 
538  //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;
539 }
Implements support for file system lookup, file system caching, and directory search management...
Definition: FileManager.h:121
Defines the clang::FileManager interface and associated types.
void GetUniqueIDMapping(SmallVectorImpl< const FileEntry *> &UIDToFiles) const
Produce an array mapping from the unique IDs assigned to each file to the corresponding FileEntry poi...
void closeFile() const
Definition: FileManager.h:103
Defines the FileSystemStatCache interface.
bool makeAbsolutePath(SmallVectorImpl< char > &Path) const
Makes Path absolute taking into account FileSystemOptions and the working directory option...
const llvm::sys::fs::UniqueID & getUniqueID() const
Definition: FileManager.h:90
#define NON_EXISTENT_DIR
NON_EXISTENT_DIR - A special value distinct from null that is used to represent a dir name that doesn...
Definition: FileManager.cpp:41
FileManager(const FileSystemOptions &FileSystemOpts, IntrusiveRefCntPtr< llvm::vfs::FileSystem > FS=nullptr)
Definition: FileManager.cpp:51
Definition: Format.h:2072
#define NON_EXISTENT_FILE
NON_EXISTENT_FILE - A special value distinct from null that is used to represent a filename that does...
Definition: FileManager.cpp:45
const FileEntry * getFile(StringRef Filename, bool OpenFile=false, bool CacheFailure=true)
Lookup, cache, and verify the specified file (real or virtual).
const DirectoryEntry * getDirectory(StringRef DirName, bool CacheFailure=true)
Lookup, cache, and verify the specified directory (real or virtual).
StringRef Filename
Definition: Format.cpp:1629
bool FixupRelativePath(SmallVectorImpl< char > &path) const
If path is not absolute and FileSystemOptions set the working directory, the path is modified to be r...
static const DirectoryEntry * getDirectoryFromFile(FileManager &FileMgr, StringRef Filename, bool CacheFailure)
Retrieve the directory that the given file name resides in.
Definition: FileManager.cpp:75
std::string WorkingDir
If set, paths are resolved as if the working directory was set to the value of WorkingDir.
The result type of a method or function.
static bool get(StringRef Path, FileData &Data, bool isFile, std::unique_ptr< llvm::vfs::File > *F, FileSystemStatCache *Cache, llvm::vfs::FileSystem &FS)
Get the &#39;stat&#39; information for the specified path, using the cache to accelerate it if possible...
llvm::sys::fs::UniqueID UniqueID
StringRef getName() const
Definition: FileManager.h:85
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:60
void PrintStats() const
const FileEntry * getVirtualFile(StringRef Filename, off_t Size, time_t ModificationTime)
Retrieve a file entry for a "virtual" file that acts as if there were a file with the given name on d...
StringRef getCanonicalName(const DirectoryEntry *Dir)
Retrieve the canonical name for a given directory.
bool isValid() const
Definition: FileManager.h:87
Dataflow Directional Tag Classes.
void clearStatCache()
Removes the FileSystemStatCache object from the manager.
Definition: FileManager.cpp:71
off_t getSize() const
Definition: FileManager.h:88
llvm::ErrorOr< std::unique_ptr< llvm::MemoryBuffer > > getBufferForFile(const FileEntry *Entry, bool isVolatile=false, bool ShouldCloseOpenFile=true)
Open the specified file as a MemoryBuffer, returning a new MemoryBuffer if successful, otherwise returning null.
bool getNoncachedStatValue(StringRef Path, llvm::vfs::Status &Result)
Get the &#39;stat&#39; information for the given Path.
Cached information about one directory (either on disk or in the virtual file system).
Definition: FileManager.h:46
void setStatCache(std::unique_ptr< FileSystemStatCache > statCache)
Installs the provided FileSystemStatCache object within the FileManager.
Definition: FileManager.cpp:66
Keeps track of options that affect how file operations are performed.
static void modifyFileEntry(FileEntry *File, off_t Size, time_t ModificationTime)
Modifies the size and modification time of a previously created FileEntry.
void invalidateCache(const FileEntry *Entry)
Remove the real file Entry from the cache.
StringRef getName() const
Definition: FileManager.h:52