1 //===--- FileManager.cpp - File System Probing and Caching ----------------===//
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 //===----------------------------------------------------------------------===//
10 // This file implements the FileManager interface.
12 //===----------------------------------------------------------------------===//
14 // TODO: This should index all interesting directories with dirent calls.
16 // opendir/readdir_r/closedir ?
18 //===----------------------------------------------------------------------===//
20 #include "clang/Basic/FileManager.h"
21 #include "clang/Basic/FileSystemStatCache.h"
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include "llvm/Support/Path.h"
28 #include "llvm/Support/system_error.h"
29 #include "llvm/Config/config.h"
34 // FIXME: This is terrible, we need this for ::close.
35 #if !defined(_MSC_VER) && !defined(__MINGW32__)
41 using namespace clang;
43 // FIXME: Enhance libsystem to support inode and other fields.
46 /// NON_EXISTENT_DIR - A special value distinct from null that is used to
47 /// represent a dir name that doesn't exist on the disk.
48 #define NON_EXISTENT_DIR reinterpret_cast<DirectoryEntry*>((intptr_t)-1)
50 /// NON_EXISTENT_FILE - A special value distinct from null that is used to
51 /// represent a filename that doesn't exist on the disk.
52 #define NON_EXISTENT_FILE reinterpret_cast<FileEntry*>((intptr_t)-1)
55 FileEntry::~FileEntry() {
56 // If this FileEntry owns an open file descriptor that never got used, close
58 if (FD != -1) ::close(FD);
61 //===----------------------------------------------------------------------===//
63 //===----------------------------------------------------------------------===//
68 static std::string GetFullPath(const char *relPath) {
69 char *absPathStrPtr = _fullpath(NULL, relPath, 0);
70 assert(absPathStrPtr && "_fullpath() returned NULL!");
72 std::string absPath(absPathStrPtr);
79 class FileManager::UniqueDirContainer {
80 /// UniqueDirs - Cache from full path to existing directories/files.
82 llvm::StringMap<DirectoryEntry> UniqueDirs;
85 /// getDirectory - Return an existing DirectoryEntry with the given
86 /// name if there is already one; otherwise create and return a
87 /// default-constructed DirectoryEntry.
88 DirectoryEntry &getDirectory(const char *Name,
89 const struct stat & /*StatBuf*/) {
90 std::string FullPath(GetFullPath(Name));
91 return UniqueDirs.GetOrCreateValue(FullPath).getValue();
94 size_t size() const { return UniqueDirs.size(); }
97 class FileManager::UniqueFileContainer {
98 /// UniqueFiles - Cache from full path to existing directories/files.
100 llvm::StringMap<FileEntry, llvm::BumpPtrAllocator> UniqueFiles;
103 /// getFile - Return an existing FileEntry with the given name if
104 /// there is already one; otherwise create and return a
105 /// default-constructed FileEntry.
106 FileEntry &getFile(const char *Name, const struct stat & /*StatBuf*/) {
107 std::string FullPath(GetFullPath(Name));
109 // LowercaseString because Windows filesystem is case insensitive.
110 FullPath = llvm::LowercaseString(FullPath);
111 return UniqueFiles.GetOrCreateValue(FullPath).getValue();
114 size_t size() const { return UniqueFiles.size(); }
117 //===----------------------------------------------------------------------===//
118 // Unix-like Systems.
119 //===----------------------------------------------------------------------===//
123 class FileManager::UniqueDirContainer {
124 /// UniqueDirs - Cache from ID's to existing directories/files.
125 std::map<std::pair<dev_t, ino_t>, DirectoryEntry> UniqueDirs;
128 /// getDirectory - Return an existing DirectoryEntry with the given
129 /// ID's if there is already one; otherwise create and return a
130 /// default-constructed DirectoryEntry.
131 DirectoryEntry &getDirectory(const char * /*Name*/,
132 const struct stat &StatBuf) {
133 return UniqueDirs[std::make_pair(StatBuf.st_dev, StatBuf.st_ino)];
136 size_t size() const { return UniqueDirs.size(); }
139 class FileManager::UniqueFileContainer {
140 /// UniqueFiles - Cache from ID's to existing directories/files.
141 std::set<FileEntry> UniqueFiles;
144 /// getFile - Return an existing FileEntry with the given ID's if
145 /// there is already one; otherwise create and return a
146 /// default-constructed FileEntry.
147 FileEntry &getFile(const char * /*Name*/, const struct stat &StatBuf) {
149 const_cast<FileEntry&>(
150 *UniqueFiles.insert(FileEntry(StatBuf.st_dev,
152 StatBuf.st_mode)).first);
155 size_t size() const { return UniqueFiles.size(); }
160 //===----------------------------------------------------------------------===//
162 //===----------------------------------------------------------------------===//
164 FileManager::FileManager(const FileSystemOptions &FSO)
165 : FileSystemOpts(FSO),
166 UniqueRealDirs(*new UniqueDirContainer()),
167 UniqueRealFiles(*new UniqueFileContainer()),
168 SeenDirEntries(64), SeenFileEntries(64), NextFileUID(0) {
169 NumDirLookups = NumFileLookups = 0;
170 NumDirCacheMisses = NumFileCacheMisses = 0;
173 FileManager::~FileManager() {
174 delete &UniqueRealDirs;
175 delete &UniqueRealFiles;
176 for (unsigned i = 0, e = VirtualFileEntries.size(); i != e; ++i)
177 delete VirtualFileEntries[i];
178 for (unsigned i = 0, e = VirtualDirectoryEntries.size(); i != e; ++i)
179 delete VirtualDirectoryEntries[i];
182 void FileManager::addStatCache(FileSystemStatCache *statCache,
184 assert(statCache && "No stat cache provided?");
185 if (AtBeginning || StatCache.get() == 0) {
186 statCache->setNextStatCache(StatCache.take());
187 StatCache.reset(statCache);
191 FileSystemStatCache *LastCache = StatCache.get();
192 while (LastCache->getNextStatCache())
193 LastCache = LastCache->getNextStatCache();
195 LastCache->setNextStatCache(statCache);
198 void FileManager::removeStatCache(FileSystemStatCache *statCache) {
202 if (StatCache.get() == statCache) {
203 // This is the first stat cache.
204 StatCache.reset(StatCache->takeNextStatCache());
208 // Find the stat cache in the list.
209 FileSystemStatCache *PrevCache = StatCache.get();
210 while (PrevCache && PrevCache->getNextStatCache() != statCache)
211 PrevCache = PrevCache->getNextStatCache();
213 assert(PrevCache && "Stat cache not found for removal");
214 PrevCache->setNextStatCache(statCache->getNextStatCache());
217 /// \brief Retrieve the directory that the given file name resides in.
218 /// Filename can point to either a real file or a virtual file.
219 static const DirectoryEntry *getDirectoryFromFile(FileManager &FileMgr,
222 if (Filename.empty())
225 if (llvm::sys::path::is_separator(Filename[Filename.size() - 1]))
226 return NULL; // If Filename is a directory.
228 StringRef DirName = llvm::sys::path::parent_path(Filename);
229 // Use the current directory if file has no path component.
233 return FileMgr.getDirectory(DirName, CacheFailure);
236 /// Add all ancestors of the given path (pointing to either a file or
237 /// a directory) as virtual directories.
238 void FileManager::addAncestorsAsVirtualDirs(StringRef Path) {
239 StringRef DirName = llvm::sys::path::parent_path(Path);
243 llvm::StringMapEntry<DirectoryEntry *> &NamedDirEnt =
244 SeenDirEntries.GetOrCreateValue(DirName);
246 // When caching a virtual directory, we always cache its ancestors
247 // at the same time. Therefore, if DirName is already in the cache,
248 // we don't need to recurse as its ancestors must also already be in
250 if (NamedDirEnt.getValue())
253 // Add the virtual directory to the cache.
254 DirectoryEntry *UDE = new DirectoryEntry;
255 UDE->Name = NamedDirEnt.getKeyData();
256 NamedDirEnt.setValue(UDE);
257 VirtualDirectoryEntries.push_back(UDE);
259 // Recursively add the other ancestors.
260 addAncestorsAsVirtualDirs(DirName);
263 /// getDirectory - Lookup, cache, and verify the specified directory
264 /// (real or virtual). This returns NULL if the directory doesn't
267 const DirectoryEntry *FileManager::getDirectory(StringRef DirName,
270 llvm::StringMapEntry<DirectoryEntry *> &NamedDirEnt =
271 SeenDirEntries.GetOrCreateValue(DirName);
273 // See if there was already an entry in the map. Note that the map
274 // contains both virtual and real directories.
275 if (NamedDirEnt.getValue())
276 return NamedDirEnt.getValue() == NON_EXISTENT_DIR
277 ? 0 : NamedDirEnt.getValue();
281 // By default, initialize it to invalid.
282 NamedDirEnt.setValue(NON_EXISTENT_DIR);
284 // Get the null-terminated directory name as stored as the key of the
285 // SeenDirEntries map.
286 const char *InterndDirName = NamedDirEnt.getKeyData();
288 // Check to see if the directory exists.
290 if (getStatValue(InterndDirName, StatBuf, 0/*directory lookup*/)) {
291 // There's no real directory at the given path.
293 SeenDirEntries.erase(DirName);
297 // It exists. See if we have already opened a directory with the
298 // same inode (this occurs on Unix-like systems when one dir is
299 // symlinked to another, for example) or the same path (on
301 DirectoryEntry &UDE = UniqueRealDirs.getDirectory(InterndDirName, StatBuf);
303 NamedDirEnt.setValue(&UDE);
304 if (!UDE.getName()) {
305 // We don't have this directory yet, add it. We use the string
306 // key from the SeenDirEntries map as the string.
307 UDE.Name = InterndDirName;
313 /// getFile - Lookup, cache, and verify the specified file (real or
314 /// virtual). This returns NULL if the file doesn't exist.
316 const FileEntry *FileManager::getFile(StringRef Filename, bool openFile,
320 // See if there is already an entry in the map.
321 llvm::StringMapEntry<FileEntry *> &NamedFileEnt =
322 SeenFileEntries.GetOrCreateValue(Filename);
324 // See if there is already an entry in the map.
325 if (NamedFileEnt.getValue())
326 return NamedFileEnt.getValue() == NON_EXISTENT_FILE
327 ? 0 : NamedFileEnt.getValue();
329 ++NumFileCacheMisses;
331 // By default, initialize it to invalid.
332 NamedFileEnt.setValue(NON_EXISTENT_FILE);
334 // Get the null-terminated file name as stored as the key of the
335 // SeenFileEntries map.
336 const char *InterndFileName = NamedFileEnt.getKeyData();
338 // Look up the directory for the file. When looking up something like
339 // sys/foo.h we'll discover all of the search directories that have a 'sys'
340 // subdirectory. This will let us avoid having to waste time on known-to-fail
341 // searches when we go to find sys/bar.h, because all the search directories
342 // without a 'sys' subdir will get a cached failure result.
343 const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
345 if (DirInfo == 0) { // Directory doesn't exist, file can't exist.
347 SeenFileEntries.erase(Filename);
352 // FIXME: Use the directory info to prune this, before doing the stat syscall.
353 // FIXME: This will reduce the # syscalls.
355 // Nope, there isn't. Check to see if the file exists.
356 int FileDescriptor = -1;
358 if (getStatValue(InterndFileName, StatBuf, &FileDescriptor)) {
359 // There's no real file at the given path.
361 SeenFileEntries.erase(Filename);
366 if (FileDescriptor != -1 && !openFile) {
367 close(FileDescriptor);
371 // It exists. See if we have already opened a file with the same inode.
372 // This occurs when one dir is symlinked to another, for example.
373 FileEntry &UFE = UniqueRealFiles.getFile(InterndFileName, StatBuf);
375 NamedFileEnt.setValue(&UFE);
376 if (UFE.getName()) { // Already have an entry with this inode, return it.
377 // If the stat process opened the file, close it to avoid a FD leak.
378 if (FileDescriptor != -1)
379 close(FileDescriptor);
384 // Otherwise, we don't have this directory yet, add it.
385 // FIXME: Change the name to be a char* that points back to the
386 // 'SeenFileEntries' key.
387 UFE.Name = InterndFileName;
388 UFE.Size = StatBuf.st_size;
389 UFE.ModTime = StatBuf.st_mtime;
391 UFE.UID = NextFileUID++;
392 UFE.FD = FileDescriptor;
397 FileManager::getVirtualFile(StringRef Filename, off_t Size,
398 time_t ModificationTime) {
401 // See if there is already an entry in the map.
402 llvm::StringMapEntry<FileEntry *> &NamedFileEnt =
403 SeenFileEntries.GetOrCreateValue(Filename);
405 // See if there is already an entry in the map.
406 if (NamedFileEnt.getValue() && NamedFileEnt.getValue() != NON_EXISTENT_FILE)
407 return NamedFileEnt.getValue();
409 ++NumFileCacheMisses;
411 // By default, initialize it to invalid.
412 NamedFileEnt.setValue(NON_EXISTENT_FILE);
414 addAncestorsAsVirtualDirs(Filename);
417 // Now that all ancestors of Filename are in the cache, the
418 // following call is guaranteed to find the DirectoryEntry from the
420 const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename,
421 /*CacheFailure=*/true);
423 "The directory of a virtual file should already be in the cache.");
425 // Check to see if the file exists. If so, drop the virtual file
426 int FileDescriptor = -1;
428 const char *InterndFileName = NamedFileEnt.getKeyData();
429 if (getStatValue(InterndFileName, StatBuf, &FileDescriptor) == 0) {
430 // If the stat process opened the file, close it to avoid a FD leak.
431 if (FileDescriptor != -1)
432 close(FileDescriptor);
434 StatBuf.st_size = Size;
435 StatBuf.st_mtime = ModificationTime;
436 UFE = &UniqueRealFiles.getFile(InterndFileName, StatBuf);
438 NamedFileEnt.setValue(UFE);
440 // If we had already opened this file, close it now so we don't
441 // leak the descriptor. We're not going to use the file
442 // descriptor anyway, since this is a virtual file.
448 // If we already have an entry with this inode, return it.
454 UFE = new FileEntry();
455 VirtualFileEntries.push_back(UFE);
456 NamedFileEnt.setValue(UFE);
459 UFE->Name = InterndFileName;
461 UFE->ModTime = ModificationTime;
463 UFE->UID = NextFileUID++;
468 void FileManager::FixupRelativePath(SmallVectorImpl<char> &path) const {
469 StringRef pathRef(path.data(), path.size());
471 if (FileSystemOpts.WorkingDir.empty()
472 || llvm::sys::path::is_absolute(pathRef))
475 llvm::SmallString<128> NewPath(FileSystemOpts.WorkingDir);
476 llvm::sys::path::append(NewPath, pathRef);
480 llvm::MemoryBuffer *FileManager::
481 getBufferForFile(const FileEntry *Entry, std::string *ErrorStr) {
482 llvm::OwningPtr<llvm::MemoryBuffer> Result;
485 const char *Filename = Entry->getName();
486 // If the file is already open, use the open file descriptor.
487 if (Entry->FD != -1) {
488 ec = llvm::MemoryBuffer::getOpenFile(Entry->FD, Filename, Result,
491 *ErrorStr = ec.message();
495 return Result.take();
498 // Otherwise, open the file.
500 if (FileSystemOpts.WorkingDir.empty()) {
501 ec = llvm::MemoryBuffer::getFile(Filename, Result, Entry->getSize());
503 *ErrorStr = ec.message();
504 return Result.take();
507 llvm::SmallString<128> FilePath(Entry->getName());
508 FixupRelativePath(FilePath);
509 ec = llvm::MemoryBuffer::getFile(FilePath.str(), Result, Entry->getSize());
511 *ErrorStr = ec.message();
512 return Result.take();
515 llvm::MemoryBuffer *FileManager::
516 getBufferForFile(StringRef Filename, std::string *ErrorStr) {
517 llvm::OwningPtr<llvm::MemoryBuffer> Result;
519 if (FileSystemOpts.WorkingDir.empty()) {
520 ec = llvm::MemoryBuffer::getFile(Filename, Result);
522 *ErrorStr = ec.message();
523 return Result.take();
526 llvm::SmallString<128> FilePath(Filename);
527 FixupRelativePath(FilePath);
528 ec = llvm::MemoryBuffer::getFile(FilePath.c_str(), Result);
530 *ErrorStr = ec.message();
531 return Result.take();
534 /// getStatValue - Get the 'stat' information for the specified path,
535 /// using the cache to accelerate it if possible. This returns true
536 /// if the path points to a virtual file or does not exist, or returns
537 /// false if it's an existent real file. If FileDescriptor is NULL,
538 /// do directory look-up instead of file look-up.
539 bool FileManager::getStatValue(const char *Path, struct stat &StatBuf,
540 int *FileDescriptor) {
541 // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
543 if (FileSystemOpts.WorkingDir.empty())
544 return FileSystemStatCache::get(Path, StatBuf, FileDescriptor,
547 llvm::SmallString<128> FilePath(Path);
548 FixupRelativePath(FilePath);
550 return FileSystemStatCache::get(FilePath.c_str(), StatBuf, FileDescriptor,
554 bool FileManager::getNoncachedStatValue(StringRef Path,
555 struct stat &StatBuf) {
556 llvm::SmallString<128> FilePath(Path);
557 FixupRelativePath(FilePath);
559 return ::stat(FilePath.c_str(), &StatBuf) != 0;
562 void FileManager::GetUniqueIDMapping(
563 SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
565 UIDToFiles.resize(NextFileUID);
568 for (llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator>::const_iterator
569 FE = SeenFileEntries.begin(), FEEnd = SeenFileEntries.end();
571 if (FE->getValue() && FE->getValue() != NON_EXISTENT_FILE)
572 UIDToFiles[FE->getValue()->getUID()] = FE->getValue();
574 // Map virtual file entries
575 for (SmallVector<FileEntry*, 4>::const_iterator
576 VFE = VirtualFileEntries.begin(), VFEEnd = VirtualFileEntries.end();
577 VFE != VFEEnd; ++VFE)
578 if (*VFE && *VFE != NON_EXISTENT_FILE)
579 UIDToFiles[(*VFE)->getUID()] = *VFE;
583 void FileManager::PrintStats() const {
584 llvm::errs() << "\n*** File Manager Stats:\n";
585 llvm::errs() << UniqueRealFiles.size() << " real files found, "
586 << UniqueRealDirs.size() << " real dirs found.\n";
587 llvm::errs() << VirtualFileEntries.size() << " virtual files found, "
588 << VirtualDirectoryEntries.size() << " virtual dirs found.\n";
589 llvm::errs() << NumDirLookups << " dir lookups, "
590 << NumDirCacheMisses << " dir cache misses.\n";
591 llvm::errs() << NumFileLookups << " file lookups, "
592 << NumFileCacheMisses << " file cache misses.\n";
594 //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;