clang  3.8.0
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 
23 #include "llvm/ADT/SmallString.h"
24 #include "llvm/Config/llvm-config.h"
25 #include "llvm/ADT/STLExtras.h"
26 #include "llvm/Support/FileSystem.h"
27 #include "llvm/Support/MemoryBuffer.h"
28 #include "llvm/Support/Path.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <map>
31 #include <set>
32 #include <string>
33 #include <system_error>
34 
35 using namespace clang;
36 
37 /// NON_EXISTENT_DIR - A special value distinct from null that is used to
38 /// represent a dir name that doesn't exist on the disk.
39 #define NON_EXISTENT_DIR reinterpret_cast<DirectoryEntry*>((intptr_t)-1)
40 
41 /// NON_EXISTENT_FILE - A special value distinct from null that is used to
42 /// represent a filename that doesn't exist on the disk.
43 #define NON_EXISTENT_FILE reinterpret_cast<FileEntry*>((intptr_t)-1)
44 
45 //===----------------------------------------------------------------------===//
46 // Common logic.
47 //===----------------------------------------------------------------------===//
48 
51  : FS(FS), FileSystemOpts(FSO),
52  SeenDirEntries(64), SeenFileEntries(64), NextFileUID(0) {
53  NumDirLookups = NumFileLookups = 0;
54  NumDirCacheMisses = NumFileCacheMisses = 0;
55 
56  // If the caller doesn't provide a virtual file system, just grab the real
57  // file system.
58  if (!FS)
59  this->FS = vfs::getRealFileSystem();
60 }
61 
62 FileManager::~FileManager() = default;
63 
64 void FileManager::addStatCache(std::unique_ptr<FileSystemStatCache> statCache,
65  bool AtBeginning) {
66  assert(statCache && "No stat cache provided?");
67  if (AtBeginning || !StatCache.get()) {
68  statCache->setNextStatCache(std::move(StatCache));
69  StatCache = std::move(statCache);
70  return;
71  }
72 
73  FileSystemStatCache *LastCache = StatCache.get();
74  while (LastCache->getNextStatCache())
75  LastCache = LastCache->getNextStatCache();
76 
77  LastCache->setNextStatCache(std::move(statCache));
78 }
79 
81  if (!statCache)
82  return;
83 
84  if (StatCache.get() == statCache) {
85  // This is the first stat cache.
86  StatCache = StatCache->takeNextStatCache();
87  return;
88  }
89 
90  // Find the stat cache in the list.
91  FileSystemStatCache *PrevCache = StatCache.get();
92  while (PrevCache && PrevCache->getNextStatCache() != statCache)
93  PrevCache = PrevCache->getNextStatCache();
94 
95  assert(PrevCache && "Stat cache not found for removal");
96  PrevCache->setNextStatCache(statCache->takeNextStatCache());
97 }
98 
100  StatCache.reset();
101 }
102 
103 /// \brief Retrieve the directory that the given file name resides in.
104 /// Filename can point to either a real file or a virtual file.
106  StringRef Filename,
107  bool CacheFailure) {
108  if (Filename.empty())
109  return nullptr;
110 
111  if (llvm::sys::path::is_separator(Filename[Filename.size() - 1]))
112  return nullptr; // If Filename is a directory.
113 
114  StringRef DirName = llvm::sys::path::parent_path(Filename);
115  // Use the current directory if file has no path component.
116  if (DirName.empty())
117  DirName = ".";
118 
119  return FileMgr.getDirectory(DirName, CacheFailure);
120 }
121 
122 /// Add all ancestors of the given path (pointing to either a file or
123 /// a directory) as virtual directories.
124 void FileManager::addAncestorsAsVirtualDirs(StringRef Path) {
125  StringRef DirName = llvm::sys::path::parent_path(Path);
126  if (DirName.empty())
127  return;
128 
129  auto &NamedDirEnt =
130  *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
131 
132  // When caching a virtual directory, we always cache its ancestors
133  // at the same time. Therefore, if DirName is already in the cache,
134  // we don't need to recurse as its ancestors must also already be in
135  // the cache.
136  if (NamedDirEnt.second && NamedDirEnt.second != NON_EXISTENT_DIR)
137  return;
138 
139  // Add the virtual directory to the cache.
140  auto UDE = llvm::make_unique<DirectoryEntry>();
141  UDE->Name = NamedDirEnt.first().data();
142  NamedDirEnt.second = UDE.get();
143  VirtualDirectoryEntries.push_back(std::move(UDE));
144 
145  // Recursively add the other ancestors.
146  addAncestorsAsVirtualDirs(DirName);
147 }
148 
149 const DirectoryEntry *FileManager::getDirectory(StringRef DirName,
150  bool CacheFailure) {
151  // stat doesn't like trailing separators except for root directory.
152  // At least, on Win32 MSVCRT, stat() cannot strip trailing '/'.
153  // (though it can strip '\\')
154  if (DirName.size() > 1 &&
155  DirName != llvm::sys::path::root_path(DirName) &&
156  llvm::sys::path::is_separator(DirName.back()))
157  DirName = DirName.substr(0, DirName.size()-1);
158 #ifdef LLVM_ON_WIN32
159  // Fixing a problem with "clang C:test.c" on Windows.
160  // Stat("C:") does not recognize "C:" as a valid directory
161  std::string DirNameStr;
162  if (DirName.size() > 1 && DirName.back() == ':' &&
163  DirName.equals_lower(llvm::sys::path::root_name(DirName))) {
164  DirNameStr = DirName.str() + '.';
165  DirName = DirNameStr;
166  }
167 #endif
168 
169  ++NumDirLookups;
170  auto &NamedDirEnt =
171  *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
172 
173  // See if there was already an entry in the map. Note that the map
174  // contains both virtual and real directories.
175  if (NamedDirEnt.second)
176  return NamedDirEnt.second == NON_EXISTENT_DIR ? nullptr
177  : NamedDirEnt.second;
178 
179  ++NumDirCacheMisses;
180 
181  // By default, initialize it to invalid.
182  NamedDirEnt.second = NON_EXISTENT_DIR;
183 
184  // Get the null-terminated directory name as stored as the key of the
185  // SeenDirEntries map.
186  const char *InterndDirName = NamedDirEnt.first().data();
187 
188  // Check to see if the directory exists.
189  FileData Data;
190  if (getStatValue(InterndDirName, Data, false, nullptr /*directory lookup*/)) {
191  // There's no real directory at the given path.
192  if (!CacheFailure)
193  SeenDirEntries.erase(DirName);
194  return nullptr;
195  }
196 
197  // It exists. See if we have already opened a directory with the
198  // same inode (this occurs on Unix-like systems when one dir is
199  // symlinked to another, for example) or the same path (on
200  // Windows).
201  DirectoryEntry &UDE = UniqueRealDirs[Data.UniqueID];
202 
203  NamedDirEnt.second = &UDE;
204  if (!UDE.getName()) {
205  // We don't have this directory yet, add it. We use the string
206  // key from the SeenDirEntries map as the string.
207  UDE.Name = InterndDirName;
208  }
209 
210  return &UDE;
211 }
212 
213 const FileEntry *FileManager::getFile(StringRef Filename, bool openFile,
214  bool CacheFailure) {
215  ++NumFileLookups;
216 
217  // See if there is already an entry in the map.
218  auto &NamedFileEnt =
219  *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
220 
221  // See if there is already an entry in the map.
222  if (NamedFileEnt.second)
223  return NamedFileEnt.second == NON_EXISTENT_FILE ? nullptr
224  : NamedFileEnt.second;
225 
226  ++NumFileCacheMisses;
227 
228  // By default, initialize it to invalid.
229  NamedFileEnt.second = NON_EXISTENT_FILE;
230 
231  // Get the null-terminated file name as stored as the key of the
232  // SeenFileEntries map.
233  const char *InterndFileName = NamedFileEnt.first().data();
234 
235  // Look up the directory for the file. When looking up something like
236  // sys/foo.h we'll discover all of the search directories that have a 'sys'
237  // subdirectory. This will let us avoid having to waste time on known-to-fail
238  // searches when we go to find sys/bar.h, because all the search directories
239  // without a 'sys' subdir will get a cached failure result.
240  const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
241  CacheFailure);
242  if (DirInfo == nullptr) { // Directory doesn't exist, file can't exist.
243  if (!CacheFailure)
244  SeenFileEntries.erase(Filename);
245 
246  return nullptr;
247  }
248 
249  // FIXME: Use the directory info to prune this, before doing the stat syscall.
250  // FIXME: This will reduce the # syscalls.
251 
252  // Nope, there isn't. Check to see if the file exists.
253  std::unique_ptr<vfs::File> F;
254  FileData Data;
255  if (getStatValue(InterndFileName, Data, true, openFile ? &F : nullptr)) {
256  // There's no real file at the given path.
257  if (!CacheFailure)
258  SeenFileEntries.erase(Filename);
259 
260  return nullptr;
261  }
262 
263  assert((openFile || !F) && "undesired open file");
264 
265  // It exists. See if we have already opened a file with the same inode.
266  // This occurs when one dir is symlinked to another, for example.
267  FileEntry &UFE = UniqueRealFiles[Data.UniqueID];
268 
269  NamedFileEnt.second = &UFE;
270 
271  // If the name returned by getStatValue is different than Filename, re-intern
272  // the name.
273  if (Data.Name != Filename) {
274  auto &NamedFileEnt =
275  *SeenFileEntries.insert(std::make_pair(Data.Name, nullptr)).first;
276  if (!NamedFileEnt.second)
277  NamedFileEnt.second = &UFE;
278  else
279  assert(NamedFileEnt.second == &UFE &&
280  "filename from getStatValue() refers to wrong file");
281  InterndFileName = NamedFileEnt.first().data();
282  }
283 
284  if (UFE.isValid()) { // Already have an entry with this inode, return it.
285 
286  // FIXME: this hack ensures that if we look up a file by a virtual path in
287  // the VFS that the getDir() will have the virtual path, even if we found
288  // the file by a 'real' path first. This is required in order to find a
289  // module's structure when its headers/module map are mapped in the VFS.
290  // We should remove this as soon as we can properly support a file having
291  // multiple names.
292  if (DirInfo != UFE.Dir && Data.IsVFSMapped)
293  UFE.Dir = DirInfo;
294 
295  // Always update the name to use the last name by which a file was accessed.
296  // FIXME: Neither this nor always using the first name is correct; we want
297  // to switch towards a design where we return a FileName object that
298  // encapsulates both the name by which the file was accessed and the
299  // corresponding FileEntry.
300  UFE.Name = InterndFileName;
301 
302  return &UFE;
303  }
304 
305  // Otherwise, we don't have this file yet, add it.
306  UFE.Name = InterndFileName;
307  UFE.Size = Data.Size;
308  UFE.ModTime = Data.ModTime;
309  UFE.Dir = DirInfo;
310  UFE.UID = NextFileUID++;
311  UFE.UniqueID = Data.UniqueID;
312  UFE.IsNamedPipe = Data.IsNamedPipe;
313  UFE.InPCH = Data.InPCH;
314  UFE.File = std::move(F);
315  UFE.IsValid = true;
316  return &UFE;
317 }
318 
319 const FileEntry *
320 FileManager::getVirtualFile(StringRef Filename, off_t Size,
321  time_t ModificationTime) {
322  ++NumFileLookups;
323 
324  // See if there is already an entry in the map.
325  auto &NamedFileEnt =
326  *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
327 
328  // See if there is already an entry in the map.
329  if (NamedFileEnt.second && NamedFileEnt.second != NON_EXISTENT_FILE)
330  return NamedFileEnt.second;
331 
332  ++NumFileCacheMisses;
333 
334  // By default, initialize it to invalid.
335  NamedFileEnt.second = NON_EXISTENT_FILE;
336 
337  addAncestorsAsVirtualDirs(Filename);
338  FileEntry *UFE = nullptr;
339 
340  // Now that all ancestors of Filename are in the cache, the
341  // following call is guaranteed to find the DirectoryEntry from the
342  // cache.
343  const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
344  /*CacheFailure=*/true);
345  assert(DirInfo &&
346  "The directory of a virtual file should already be in the cache.");
347 
348  // Check to see if the file exists. If so, drop the virtual file
349  FileData Data;
350  const char *InterndFileName = NamedFileEnt.first().data();
351  if (getStatValue(InterndFileName, Data, true, nullptr) == 0) {
352  Data.Size = Size;
353  Data.ModTime = ModificationTime;
354  UFE = &UniqueRealFiles[Data.UniqueID];
355 
356  NamedFileEnt.second = UFE;
357 
358  // If we had already opened this file, close it now so we don't
359  // leak the descriptor. We're not going to use the file
360  // descriptor anyway, since this is a virtual file.
361  if (UFE->File)
362  UFE->closeFile();
363 
364  // If we already have an entry with this inode, return it.
365  if (UFE->isValid())
366  return UFE;
367 
368  UFE->UniqueID = Data.UniqueID;
369  UFE->IsNamedPipe = Data.IsNamedPipe;
370  UFE->InPCH = Data.InPCH;
371  }
372 
373  if (!UFE) {
374  VirtualFileEntries.push_back(llvm::make_unique<FileEntry>());
375  UFE = VirtualFileEntries.back().get();
376  NamedFileEnt.second = UFE;
377  }
378 
379  UFE->Name = InterndFileName;
380  UFE->Size = Size;
381  UFE->ModTime = ModificationTime;
382  UFE->Dir = DirInfo;
383  UFE->UID = NextFileUID++;
384  UFE->File.reset();
385  return UFE;
386 }
387 
389  StringRef pathRef(path.data(), path.size());
390 
391  if (FileSystemOpts.WorkingDir.empty()
392  || llvm::sys::path::is_absolute(pathRef))
393  return false;
394 
395  SmallString<128> NewPath(FileSystemOpts.WorkingDir);
396  llvm::sys::path::append(NewPath, pathRef);
397  path = NewPath;
398  return true;
399 }
400 
402  bool Changed = FixupRelativePath(Path);
403 
404  if (!llvm::sys::path::is_absolute(StringRef(Path.data(), Path.size()))) {
405  llvm::sys::fs::make_absolute(Path);
406  Changed = true;
407  }
408 
409  return Changed;
410 }
411 
412 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
413 FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
414  bool ShouldCloseOpenFile) {
415  uint64_t FileSize = Entry->getSize();
416  // If there's a high enough chance that the file have changed since we
417  // got its size, force a stat before opening it.
418  if (isVolatile)
419  FileSize = -1;
420 
421  const char *Filename = Entry->getName();
422  // If the file is already open, use the open file descriptor.
423  if (Entry->File) {
424  auto Result =
425  Entry->File->getBuffer(Filename, FileSize,
426  /*RequiresNullTerminator=*/true, isVolatile);
427  // FIXME: we need a set of APIs that can make guarantees about whether a
428  // FileEntry is open or not.
429  if (ShouldCloseOpenFile)
430  Entry->closeFile();
431  return Result;
432  }
433 
434  // Otherwise, open the file.
435 
436  if (FileSystemOpts.WorkingDir.empty())
437  return FS->getBufferForFile(Filename, FileSize,
438  /*RequiresNullTerminator=*/true, isVolatile);
439 
442  return FS->getBufferForFile(FilePath, FileSize,
443  /*RequiresNullTerminator=*/true, isVolatile);
444 }
445 
446 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
448  if (FileSystemOpts.WorkingDir.empty())
449  return FS->getBufferForFile(Filename);
450 
451  SmallString<128> FilePath(Filename);
452  FixupRelativePath(FilePath);
453  return FS->getBufferForFile(FilePath.c_str());
454 }
455 
456 /// getStatValue - Get the 'stat' information for the specified path,
457 /// using the cache to accelerate it if possible. This returns true
458 /// if the path points to a virtual file or does not exist, or returns
459 /// false if it's an existent real file. If FileDescriptor is NULL,
460 /// do directory look-up instead of file look-up.
461 bool FileManager::getStatValue(const char *Path, FileData &Data, bool isFile,
462  std::unique_ptr<vfs::File> *F) {
463  // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
464  // absolute!
465  if (FileSystemOpts.WorkingDir.empty())
466  return FileSystemStatCache::get(Path, Data, isFile, F,StatCache.get(), *FS);
467 
470 
471  return FileSystemStatCache::get(FilePath.c_str(), Data, isFile, F,
472  StatCache.get(), *FS);
473 }
474 
476  vfs::Status &Result) {
478  FixupRelativePath(FilePath);
479 
480  llvm::ErrorOr<vfs::Status> S = FS->status(FilePath.c_str());
481  if (!S)
482  return true;
483  Result = *S;
484  return false;
485 }
486 
488  assert(Entry && "Cannot invalidate a NULL FileEntry");
489 
490  SeenFileEntries.erase(Entry->getName());
491 
492  // FileEntry invalidation should not block future optimizations in the file
493  // caches. Possible alternatives are cache truncation (invalidate last N) or
494  // invalidation of the whole cache.
495  UniqueRealFiles.erase(Entry->getUniqueID());
496 }
497 
498 
500  SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
501  UIDToFiles.clear();
502  UIDToFiles.resize(NextFileUID);
503 
504  // Map file entries
505  for (llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator>::const_iterator
506  FE = SeenFileEntries.begin(), FEEnd = SeenFileEntries.end();
507  FE != FEEnd; ++FE)
508  if (FE->getValue() && FE->getValue() != NON_EXISTENT_FILE)
509  UIDToFiles[FE->getValue()->getUID()] = FE->getValue();
510 
511  // Map virtual file entries
512  for (const auto &VFE : VirtualFileEntries)
513  if (VFE && VFE.get() != NON_EXISTENT_FILE)
514  UIDToFiles[VFE->getUID()] = VFE.get();
515 }
516 
518  off_t Size, time_t ModificationTime) {
519  File->Size = Size;
520  File->ModTime = ModificationTime;
521 }
522 
524  // FIXME: use llvm::sys::fs::canonical() when it gets implemented
526  = CanonicalDirNames.find(Dir);
527  if (Known != CanonicalDirNames.end())
528  return Known->second;
529 
530  StringRef CanonicalName(Dir->getName());
531 
532 #ifdef LLVM_ON_UNIX
533  char CanonicalNameBuf[PATH_MAX];
534  if (realpath(Dir->getName(), CanonicalNameBuf))
535  CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
536 #else
537  SmallString<256> CanonicalNameBuf(CanonicalName);
538  llvm::sys::fs::make_absolute(CanonicalNameBuf);
539  llvm::sys::path::native(CanonicalNameBuf);
540  // We've run into needing to remove '..' here in the wild though, so
541  // remove it.
542  // On Windows, symlinks are significantly less prevalent, so removing
543  // '..' is pretty safe.
544  // Ideally we'd have an equivalent of `realpath` and could implement
545  // sys::fs::canonical across all the platforms.
546  llvm::sys::path::remove_dots(CanonicalNameBuf, /* remove_dot_dot */ true);
547  CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
548 #endif
549 
550  CanonicalDirNames.insert(std::make_pair(Dir, CanonicalName));
551  return CanonicalName;
552 }
553 
555  llvm::errs() << "\n*** File Manager Stats:\n";
556  llvm::errs() << UniqueRealFiles.size() << " real files found, "
557  << UniqueRealDirs.size() << " real dirs found.\n";
558  llvm::errs() << VirtualFileEntries.size() << " virtual files found, "
559  << VirtualDirectoryEntries.size() << " virtual dirs found.\n";
560  llvm::errs() << NumDirLookups << " dir lookups, "
561  << NumDirCacheMisses << " dir cache misses.\n";
562  llvm::errs() << NumFileLookups << " file lookups, "
563  << NumFileCacheMisses << " file cache misses.\n";
564 
565  //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;
566 }
567 
568 // Virtual destructors for abstract base classes that need live in Basic.
Implements support for file system lookup, file system caching, and directory search management...
Definition: FileManager.h:115
Defines the clang::FileManager interface and associated types.
IntrusiveRefCntPtr< FileSystem > getRealFileSystem()
Gets an vfs::FileSystem for the 'real' file system, as seen by the operating system.
bool isValid() const
Definition: FileManager.h:85
Defines the FileSystemStatCache interface.
FileManager(const FileSystemOptions &FileSystemOpts, IntrusiveRefCntPtr< vfs::FileSystem > FS=nullptr)
Definition: FileManager.cpp:49
static bool get(const char *Path, FileData &Data, bool isFile, std::unique_ptr< vfs::File > *F, FileSystemStatCache *Cache, vfs::FileSystem &FS)
Get the 'stat' information for the specified path, using the cache to accelerate it if possible...
#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:39
off_t getSize() const
Definition: FileManager.h:86
const StringRef FilePath
#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:43
bool makeAbsolutePath(SmallVectorImpl< char > &Path) const
Makes Path absolute taking into account FileSystemOptions and the working directory option...
Abstract interface for introducing a FileManager cache for 'stat' system calls, which is used by prec...
std::unique_ptr< FileSystemStatCache > takeNextStatCache()
Retrieve the next stat call cache in the chain, transferring ownership of this cache (and...
The result of a status operation.
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:1723
static const DirectoryEntry * getDirectoryFromFile(FileManager &FileMgr, StringRef Filename, bool CacheFailure)
Retrieve the directory that the given file name resides in.
const llvm::sys::fs::UniqueID & getUniqueID() const
Definition: FileManager.h:88
void setNextStatCache(std::unique_ptr< FileSystemStatCache > Cache)
Sets the next stat call cache in the chain of stat caches.
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.
void addStatCache(std::unique_ptr< FileSystemStatCache > statCache, bool AtBeginning=false)
Installs the provided FileSystemStatCache object within the FileManager.
Definition: FileManager.cpp:64
const char * getName() const
Definition: FileManager.h:84
llvm::sys::fs::UniqueID UniqueID
const TemplateArgument * iterator
Definition: Type.h:4070
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:53
void clearStatCaches()
Removes all FileSystemStatCache objects from the manager.
Definition: FileManager.cpp:99
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...
const char * getName() const
Definition: FileManager.h:45
StringRef getCanonicalName(const DirectoryEntry *Dir)
Retrieve the canonical name for a given directory.
void removeStatCache(FileSystemStatCache *statCache)
Removes the specified FileSystemStatCache object from the manager.
Definition: FileManager.cpp:80
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.
void closeFile() const
Definition: FileManager.h:101
Cached information about one directory (either on disk or in the virtual file system).
Definition: FileManager.h:40
Keeps track of options that affect how file operations are performed.
bool getNoncachedStatValue(StringRef Path, vfs::Status &Result)
Get the 'stat' information for the given Path.
static void modifyFileEntry(FileEntry *File, off_t Size, time_t ModificationTime)
Modifies the size and modification time of a previously created FileEntry.
void PrintStats() const
void invalidateCache(const FileEntry *Entry)
Remove the real file Entry from the cache.
bool FixupRelativePath(SmallVectorImpl< char > &path) const
If path is not absolute and FileSystemOptions set the working directory, the path is modified to be r...
FileSystemStatCache * getNextStatCache()
Retrieve the next stat call cache in the chain.
void GetUniqueIDMapping(SmallVectorImpl< const FileEntry * > &UIDToFiles) const
Produce an array mapping from the unique IDs assigned to each file to the corresponding FileEntry poi...