1 //===--- FileManager.cpp - File System Probing and Caching ----------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the FileManager interface.
10 //
11 //===----------------------------------------------------------------------===//
12 //
13 // TODO: This should index all interesting directories with dirent calls.
14 // getdirentries ?
15 // opendir/readdir_r/closedir ?
16 //
17 //===----------------------------------------------------------------------===//
18
19 #include "clang/Basic/FileManager.h"
20 #include "clang/Basic/FileSystemStatCache.h"
21 #include "llvm/ADT/STLExtras.h"
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/ADT/Statistic.h"
24 #include "llvm/Config/llvm-config.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 #define DEBUG_TYPE "file-search"
40
41 ALWAYS_ENABLED_STATISTIC(NumDirLookups, "Number of directory lookups.");
42 ALWAYS_ENABLED_STATISTIC(NumFileLookups, "Number of file lookups.");
43 ALWAYS_ENABLED_STATISTIC(NumDirCacheMisses,
44 "Number of directory cache misses.");
45 ALWAYS_ENABLED_STATISTIC(NumFileCacheMisses, "Number of file cache misses.");
46
47 //===----------------------------------------------------------------------===//
48 // Common logic.
49 //===----------------------------------------------------------------------===//
50
FileManager(const FileSystemOptions & FSO,IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS)51 FileManager::FileManager(const FileSystemOptions &FSO,
52 IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS)
53 : FS(std::move(FS)), FileSystemOpts(FSO), SeenDirEntries(64),
54 SeenFileEntries(64), NextFileUID(0) {
55 // If the caller doesn't provide a virtual file system, just grab the real
56 // file system.
57 if (!this->FS)
58 this->FS = llvm::vfs::getRealFileSystem();
59 }
60
61 FileManager::~FileManager() = default;
62
setStatCache(std::unique_ptr<FileSystemStatCache> statCache)63 void FileManager::setStatCache(std::unique_ptr<FileSystemStatCache> statCache) {
64 assert(statCache && "No stat cache provided?");
65 StatCache = std::move(statCache);
66 }
67
clearStatCache()68 void FileManager::clearStatCache() { StatCache.reset(); }
69
70 /// Retrieve the directory that the given file name resides in.
71 /// Filename can point to either a real file or a virtual file.
72 static llvm::Expected<DirectoryEntryRef>
getDirectoryFromFile(FileManager & FileMgr,StringRef Filename,bool CacheFailure)73 getDirectoryFromFile(FileManager &FileMgr, StringRef Filename,
74 bool CacheFailure) {
75 if (Filename.empty())
76 return llvm::errorCodeToError(
77 make_error_code(std::errc::no_such_file_or_directory));
78
79 if (llvm::sys::path::is_separator(Filename[Filename.size() - 1]))
80 return llvm::errorCodeToError(make_error_code(std::errc::is_a_directory));
81
82 StringRef DirName = llvm::sys::path::parent_path(Filename);
83 // Use the current directory if file has no path component.
84 if (DirName.empty())
85 DirName = ".";
86
87 return FileMgr.getDirectoryRef(DirName, CacheFailure);
88 }
89
90 /// Add all ancestors of the given path (pointing to either a file or
91 /// a directory) as virtual directories.
addAncestorsAsVirtualDirs(StringRef Path)92 void FileManager::addAncestorsAsVirtualDirs(StringRef Path) {
93 StringRef DirName = llvm::sys::path::parent_path(Path);
94 if (DirName.empty())
95 DirName = ".";
96
97 auto &NamedDirEnt = *SeenDirEntries.insert(
98 {DirName, std::errc::no_such_file_or_directory}).first;
99
100 // When caching a virtual directory, we always cache its ancestors
101 // at the same time. Therefore, if DirName is already in the cache,
102 // we don't need to recurse as its ancestors must also already be in
103 // the cache (or it's a known non-virtual directory).
104 if (NamedDirEnt.second)
105 return;
106
107 // Add the virtual directory to the cache.
108 auto UDE = std::make_unique<DirectoryEntry>();
109 UDE->Name = NamedDirEnt.first();
110 NamedDirEnt.second = *UDE.get();
111 VirtualDirectoryEntries.push_back(std::move(UDE));
112
113 // Recursively add the other ancestors.
114 addAncestorsAsVirtualDirs(DirName);
115 }
116
117 llvm::Expected<DirectoryEntryRef>
getDirectoryRef(StringRef DirName,bool CacheFailure)118 FileManager::getDirectoryRef(StringRef DirName, bool CacheFailure) {
119 // stat doesn't like trailing separators except for root directory.
120 // At least, on Win32 MSVCRT, stat() cannot strip trailing '/'.
121 // (though it can strip '\\')
122 if (DirName.size() > 1 &&
123 DirName != llvm::sys::path::root_path(DirName) &&
124 llvm::sys::path::is_separator(DirName.back()))
125 DirName = DirName.substr(0, DirName.size()-1);
126 #ifdef _WIN32
127 // Fixing a problem with "clang C:test.c" on Windows.
128 // Stat("C:") does not recognize "C:" as a valid directory
129 std::string DirNameStr;
130 if (DirName.size() > 1 && DirName.back() == ':' &&
131 DirName.equals_lower(llvm::sys::path::root_name(DirName))) {
132 DirNameStr = DirName.str() + '.';
133 DirName = DirNameStr;
134 }
135 #endif
136
137 ++NumDirLookups;
138
139 // See if there was already an entry in the map. Note that the map
140 // contains both virtual and real directories.
141 auto SeenDirInsertResult =
142 SeenDirEntries.insert({DirName, std::errc::no_such_file_or_directory});
143 if (!SeenDirInsertResult.second) {
144 if (SeenDirInsertResult.first->second)
145 return DirectoryEntryRef(*SeenDirInsertResult.first);
146 return llvm::errorCodeToError(SeenDirInsertResult.first->second.getError());
147 }
148
149 // We've not seen this before. Fill it in.
150 ++NumDirCacheMisses;
151 auto &NamedDirEnt = *SeenDirInsertResult.first;
152 assert(!NamedDirEnt.second && "should be newly-created");
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 llvm::vfs::Status Status;
160 auto statError = getStatValue(InterndDirName, Status, false,
161 nullptr /*directory lookup*/);
162 if (statError) {
163 // There's no real directory at the given path.
164 if (CacheFailure)
165 NamedDirEnt.second = statError;
166 else
167 SeenDirEntries.erase(DirName);
168 return llvm::errorCodeToError(statError);
169 }
170
171 // It exists. See if we have already opened a directory with the
172 // same inode (this occurs on Unix-like systems when one dir is
173 // symlinked to another, for example) or the same path (on
174 // Windows).
175 DirectoryEntry &UDE = UniqueRealDirs[Status.getUniqueID()];
176
177 NamedDirEnt.second = UDE;
178 if (UDE.getName().empty()) {
179 // We don't have this directory yet, add it. We use the string
180 // key from the SeenDirEntries map as the string.
181 UDE.Name = InterndDirName;
182 }
183
184 return DirectoryEntryRef(NamedDirEnt);
185 }
186
187 llvm::ErrorOr<const DirectoryEntry *>
getDirectory(StringRef DirName,bool CacheFailure)188 FileManager::getDirectory(StringRef DirName, bool CacheFailure) {
189 auto Result = getDirectoryRef(DirName, CacheFailure);
190 if (Result)
191 return &Result->getDirEntry();
192 return llvm::errorToErrorCode(Result.takeError());
193 }
194
195 llvm::ErrorOr<const FileEntry *>
getFile(StringRef Filename,bool openFile,bool CacheFailure)196 FileManager::getFile(StringRef Filename, bool openFile, bool CacheFailure) {
197 auto Result = getFileRef(Filename, openFile, CacheFailure);
198 if (Result)
199 return &Result->getFileEntry();
200 return llvm::errorToErrorCode(Result.takeError());
201 }
202
203 llvm::Expected<FileEntryRef>
getFileRef(StringRef Filename,bool openFile,bool CacheFailure)204 FileManager::getFileRef(StringRef Filename, bool openFile, bool CacheFailure) {
205 ++NumFileLookups;
206
207 // See if there is already an entry in the map.
208 auto SeenFileInsertResult =
209 SeenFileEntries.insert({Filename, std::errc::no_such_file_or_directory});
210 if (!SeenFileInsertResult.second) {
211 if (!SeenFileInsertResult.first->second)
212 return llvm::errorCodeToError(
213 SeenFileInsertResult.first->second.getError());
214 // Construct and return and FileEntryRef, unless it's a redirect to another
215 // filename.
216 FileEntryRef::MapValue Value = *SeenFileInsertResult.first->second;
217 if (LLVM_LIKELY(Value.V.is<FileEntry *>()))
218 return FileEntryRef(*SeenFileInsertResult.first);
219 return FileEntryRef(*reinterpret_cast<const FileEntryRef::MapEntry *>(
220 Value.V.get<const void *>()));
221 }
222
223 // We've not seen this before. Fill it in.
224 ++NumFileCacheMisses;
225 auto *NamedFileEnt = &*SeenFileInsertResult.first;
226 assert(!NamedFileEnt->second && "should be newly-created");
227
228 // Get the null-terminated file name as stored as the key of the
229 // SeenFileEntries map.
230 StringRef InterndFileName = NamedFileEnt->first();
231
232 // Look up the directory for the file. When looking up something like
233 // sys/foo.h we'll discover all of the search directories that have a 'sys'
234 // subdirectory. This will let us avoid having to waste time on known-to-fail
235 // searches when we go to find sys/bar.h, because all the search directories
236 // without a 'sys' subdir will get a cached failure result.
237 auto DirInfoOrErr = getDirectoryFromFile(*this, Filename, CacheFailure);
238 if (!DirInfoOrErr) { // Directory doesn't exist, file can't exist.
239 std::error_code Err = errorToErrorCode(DirInfoOrErr.takeError());
240 if (CacheFailure)
241 NamedFileEnt->second = Err;
242 else
243 SeenFileEntries.erase(Filename);
244
245 return llvm::errorCodeToError(Err);
246 }
247 DirectoryEntryRef DirInfo = *DirInfoOrErr;
248
249 // FIXME: Use the directory info to prune this, before doing the stat syscall.
250 // FIXME: This will reduce the # syscalls.
251
252 // Check to see if the file exists.
253 std::unique_ptr<llvm::vfs::File> F;
254 llvm::vfs::Status Status;
255 auto statError = getStatValue(InterndFileName, Status, true,
256 openFile ? &F : nullptr);
257 if (statError) {
258 // There's no real file at the given path.
259 if (CacheFailure)
260 NamedFileEnt->second = statError;
261 else
262 SeenFileEntries.erase(Filename);
263
264 return llvm::errorCodeToError(statError);
265 }
266
267 assert((openFile || !F) && "undesired open file");
268
269 // It exists. See if we have already opened a file with the same inode.
270 // This occurs when one dir is symlinked to another, for example.
271 FileEntry &UFE = UniqueRealFiles[Status.getUniqueID()];
272
273 if (Status.getName() == Filename) {
274 // The name matches. Set the FileEntry.
275 NamedFileEnt->second = FileEntryRef::MapValue(UFE, DirInfo);
276 } else {
277 // Name mismatch. We need a redirect. First grab the actual entry we want
278 // to return.
279 auto &Redirection =
280 *SeenFileEntries
281 .insert({Status.getName(), FileEntryRef::MapValue(UFE, DirInfo)})
282 .first;
283 assert(Redirection.second->V.is<FileEntry *>() &&
284 "filename redirected to a non-canonical filename?");
285 assert(Redirection.second->V.get<FileEntry *>() == &UFE &&
286 "filename from getStatValue() refers to wrong file");
287
288 // Cache the redirection in the previously-inserted entry, still available
289 // in the tentative return value.
290 NamedFileEnt->second = FileEntryRef::MapValue(Redirection);
291
292 // Fix the tentative return value.
293 NamedFileEnt = &Redirection;
294 }
295
296 FileEntryRef ReturnedRef(*NamedFileEnt);
297 if (UFE.isValid()) { // Already have an entry with this inode, return it.
298
299 // FIXME: this hack ensures that if we look up a file by a virtual path in
300 // the VFS that the getDir() will have the virtual path, even if we found
301 // the file by a 'real' path first. This is required in order to find a
302 // module's structure when its headers/module map are mapped in the VFS.
303 // We should remove this as soon as we can properly support a file having
304 // multiple names.
305 if (&DirInfo.getDirEntry() != UFE.Dir && Status.IsVFSMapped)
306 UFE.Dir = &DirInfo.getDirEntry();
307
308 // Always update LastRef to the last name by which a file was accessed.
309 // FIXME: Neither this nor always using the first reference is correct; we
310 // want to switch towards a design where we return a FileName object that
311 // encapsulates both the name by which the file was accessed and the
312 // corresponding FileEntry.
313 // FIXME: LastRef should be removed from FileEntry once all clients adopt
314 // FileEntryRef.
315 UFE.LastRef = ReturnedRef;
316
317 return ReturnedRef;
318 }
319
320 // Otherwise, we don't have this file yet, add it.
321 UFE.LastRef = ReturnedRef;
322 UFE.Size = Status.getSize();
323 UFE.ModTime = llvm::sys::toTimeT(Status.getLastModificationTime());
324 UFE.Dir = &DirInfo.getDirEntry();
325 UFE.UID = NextFileUID++;
326 UFE.UniqueID = Status.getUniqueID();
327 UFE.IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file;
328 UFE.File = std::move(F);
329 UFE.IsValid = true;
330
331 if (UFE.File) {
332 if (auto PathName = UFE.File->getName())
333 fillRealPathName(&UFE, *PathName);
334 } else if (!openFile) {
335 // We should still fill the path even if we aren't opening the file.
336 fillRealPathName(&UFE, InterndFileName);
337 }
338 return ReturnedRef;
339 }
340
getSTDIN()341 llvm::Expected<FileEntryRef> FileManager::getSTDIN() {
342 // Only read stdin once.
343 if (STDIN)
344 return *STDIN;
345
346 std::unique_ptr<llvm::MemoryBuffer> Content;
347 if (auto ContentOrError = llvm::MemoryBuffer::getSTDIN())
348 Content = std::move(*ContentOrError);
349 else
350 return llvm::errorCodeToError(ContentOrError.getError());
351
352 STDIN = getVirtualFileRef(Content->getBufferIdentifier(),
353 Content->getBufferSize(), 0);
354 FileEntry &FE = const_cast<FileEntry &>(STDIN->getFileEntry());
355 FE.Content = std::move(Content);
356 FE.IsNamedPipe = true;
357 return *STDIN;
358 }
359
getVirtualFile(StringRef Filename,off_t Size,time_t ModificationTime)360 const FileEntry *FileManager::getVirtualFile(StringRef Filename, off_t Size,
361 time_t ModificationTime) {
362 return &getVirtualFileRef(Filename, Size, ModificationTime).getFileEntry();
363 }
364
getVirtualFileRef(StringRef Filename,off_t Size,time_t ModificationTime)365 FileEntryRef FileManager::getVirtualFileRef(StringRef Filename, off_t Size,
366 time_t ModificationTime) {
367 ++NumFileLookups;
368
369 // See if there is already an entry in the map for an existing file.
370 auto &NamedFileEnt = *SeenFileEntries.insert(
371 {Filename, std::errc::no_such_file_or_directory}).first;
372 if (NamedFileEnt.second) {
373 FileEntryRef::MapValue Value = *NamedFileEnt.second;
374 if (LLVM_LIKELY(Value.V.is<FileEntry *>()))
375 return FileEntryRef(NamedFileEnt);
376 return FileEntryRef(*reinterpret_cast<const FileEntryRef::MapEntry *>(
377 Value.V.get<const void *>()));
378 }
379
380 // We've not seen this before, or the file is cached as non-existent.
381 ++NumFileCacheMisses;
382 addAncestorsAsVirtualDirs(Filename);
383 FileEntry *UFE = nullptr;
384
385 // Now that all ancestors of Filename are in the cache, the
386 // following call is guaranteed to find the DirectoryEntry from the
387 // cache. A virtual file can also have an empty filename, that could come
388 // from a source location preprocessor directive with an empty filename as
389 // an example, so we need to pretend it has a name to ensure a valid directory
390 // entry can be returned.
391 auto DirInfo = expectedToOptional(getDirectoryFromFile(
392 *this, Filename.empty() ? "." : Filename, /*CacheFailure=*/true));
393 assert(DirInfo &&
394 "The directory of a virtual file should already be in the cache.");
395
396 // Check to see if the file exists. If so, drop the virtual file
397 llvm::vfs::Status Status;
398 const char *InterndFileName = NamedFileEnt.first().data();
399 if (!getStatValue(InterndFileName, Status, true, nullptr)) {
400 UFE = &UniqueRealFiles[Status.getUniqueID()];
401 Status = llvm::vfs::Status(
402 Status.getName(), Status.getUniqueID(),
403 llvm::sys::toTimePoint(ModificationTime),
404 Status.getUser(), Status.getGroup(), Size,
405 Status.getType(), Status.getPermissions());
406
407 NamedFileEnt.second = FileEntryRef::MapValue(*UFE, *DirInfo);
408
409 // If we had already opened this file, close it now so we don't
410 // leak the descriptor. We're not going to use the file
411 // descriptor anyway, since this is a virtual file.
412 if (UFE->File)
413 UFE->closeFile();
414
415 // If we already have an entry with this inode, return it.
416 //
417 // FIXME: Surely this should add a reference by the new name, and return
418 // it instead...
419 if (UFE->isValid())
420 return FileEntryRef(NamedFileEnt);
421
422 UFE->UniqueID = Status.getUniqueID();
423 UFE->IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file;
424 fillRealPathName(UFE, Status.getName());
425 } else {
426 VirtualFileEntries.push_back(std::make_unique<FileEntry>());
427 UFE = VirtualFileEntries.back().get();
428 NamedFileEnt.second = FileEntryRef::MapValue(*UFE, *DirInfo);
429 }
430
431 UFE->LastRef = FileEntryRef(NamedFileEnt);
432 UFE->Size = Size;
433 UFE->ModTime = ModificationTime;
434 UFE->Dir = &DirInfo->getDirEntry();
435 UFE->UID = NextFileUID++;
436 UFE->IsValid = true;
437 UFE->File.reset();
438 return FileEntryRef(NamedFileEnt);
439 }
440
getBypassFile(FileEntryRef VF)441 llvm::Optional<FileEntryRef> FileManager::getBypassFile(FileEntryRef VF) {
442 // Stat of the file and return nullptr if it doesn't exist.
443 llvm::vfs::Status Status;
444 if (getStatValue(VF.getName(), Status, /*isFile=*/true, /*F=*/nullptr))
445 return None;
446
447 if (!SeenBypassFileEntries)
448 SeenBypassFileEntries = std::make_unique<
449 llvm::StringMap<llvm::ErrorOr<FileEntryRef::MapValue>>>();
450
451 // If we've already bypassed just use the existing one.
452 auto Insertion = SeenBypassFileEntries->insert(
453 {VF.getName(), std::errc::no_such_file_or_directory});
454 if (!Insertion.second)
455 return FileEntryRef(*Insertion.first);
456
457 // Fill in the new entry from the stat.
458 BypassFileEntries.push_back(std::make_unique<FileEntry>());
459 const FileEntry &VFE = VF.getFileEntry();
460 FileEntry &BFE = *BypassFileEntries.back();
461 Insertion.first->second = FileEntryRef::MapValue(BFE, VF.getDir());
462 BFE.LastRef = FileEntryRef(*Insertion.first);
463 BFE.Size = Status.getSize();
464 BFE.Dir = VFE.Dir;
465 BFE.ModTime = llvm::sys::toTimeT(Status.getLastModificationTime());
466 BFE.UID = NextFileUID++;
467 BFE.IsValid = true;
468
469 // Save the entry in the bypass table and return.
470 return FileEntryRef(*Insertion.first);
471 }
472
FixupRelativePath(SmallVectorImpl<char> & path) const473 bool FileManager::FixupRelativePath(SmallVectorImpl<char> &path) const {
474 StringRef pathRef(path.data(), path.size());
475
476 if (FileSystemOpts.WorkingDir.empty()
477 || llvm::sys::path::is_absolute(pathRef))
478 return false;
479
480 SmallString<128> NewPath(FileSystemOpts.WorkingDir);
481 llvm::sys::path::append(NewPath, pathRef);
482 path = NewPath;
483 return true;
484 }
485
makeAbsolutePath(SmallVectorImpl<char> & Path) const486 bool FileManager::makeAbsolutePath(SmallVectorImpl<char> &Path) const {
487 bool Changed = FixupRelativePath(Path);
488
489 if (!llvm::sys::path::is_absolute(StringRef(Path.data(), Path.size()))) {
490 FS->makeAbsolute(Path);
491 Changed = true;
492 }
493
494 return Changed;
495 }
496
fillRealPathName(FileEntry * UFE,llvm::StringRef FileName)497 void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
498 llvm::SmallString<128> AbsPath(FileName);
499 // This is not the same as `VFS::getRealPath()`, which resolves symlinks
500 // but can be very expensive on real file systems.
501 // FIXME: the semantic of RealPathName is unclear, and the name might be
502 // misleading. We need to clean up the interface here.
503 makeAbsolutePath(AbsPath);
504 llvm::sys::path::remove_dots(AbsPath, /*remove_dot_dot=*/true);
505 UFE->RealPathName = std::string(AbsPath.str());
506 }
507
508 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFile(const FileEntry * Entry,bool isVolatile,bool RequiresNullTerminator)509 FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
510 bool RequiresNullTerminator) {
511 // If the content is living on the file entry, return a reference to it.
512 if (Entry->Content)
513 return llvm::MemoryBuffer::getMemBuffer(Entry->Content->getMemBufferRef());
514
515 uint64_t FileSize = Entry->getSize();
516 // If there's a high enough chance that the file have changed since we
517 // got its size, force a stat before opening it.
518 if (isVolatile || Entry->isNamedPipe())
519 FileSize = -1;
520
521 StringRef Filename = Entry->getName();
522 // If the file is already open, use the open file descriptor.
523 if (Entry->File) {
524 auto Result = Entry->File->getBuffer(Filename, FileSize,
525 RequiresNullTerminator, isVolatile);
526 Entry->closeFile();
527 return Result;
528 }
529
530 // Otherwise, open the file.
531 return getBufferForFileImpl(Filename, FileSize, isVolatile,
532 RequiresNullTerminator);
533 }
534
535 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
getBufferForFileImpl(StringRef Filename,int64_t FileSize,bool isVolatile,bool RequiresNullTerminator)536 FileManager::getBufferForFileImpl(StringRef Filename, int64_t FileSize,
537 bool isVolatile,
538 bool RequiresNullTerminator) {
539 if (FileSystemOpts.WorkingDir.empty())
540 return FS->getBufferForFile(Filename, FileSize, RequiresNullTerminator,
541 isVolatile);
542
543 SmallString<128> FilePath(Filename);
544 FixupRelativePath(FilePath);
545 return FS->getBufferForFile(FilePath, FileSize, RequiresNullTerminator,
546 isVolatile);
547 }
548
549 /// getStatValue - Get the 'stat' information for the specified path,
550 /// using the cache to accelerate it if possible. This returns true
551 /// if the path points to a virtual file or does not exist, or returns
552 /// false if it's an existent real file. If FileDescriptor is NULL,
553 /// do directory look-up instead of file look-up.
554 std::error_code
getStatValue(StringRef Path,llvm::vfs::Status & Status,bool isFile,std::unique_ptr<llvm::vfs::File> * F)555 FileManager::getStatValue(StringRef Path, llvm::vfs::Status &Status,
556 bool isFile, std::unique_ptr<llvm::vfs::File> *F) {
557 // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
558 // absolute!
559 if (FileSystemOpts.WorkingDir.empty())
560 return FileSystemStatCache::get(Path, Status, isFile, F,
561 StatCache.get(), *FS);
562
563 SmallString<128> FilePath(Path);
564 FixupRelativePath(FilePath);
565
566 return FileSystemStatCache::get(FilePath.c_str(), Status, isFile, F,
567 StatCache.get(), *FS);
568 }
569
570 std::error_code
getNoncachedStatValue(StringRef Path,llvm::vfs::Status & Result)571 FileManager::getNoncachedStatValue(StringRef Path,
572 llvm::vfs::Status &Result) {
573 SmallString<128> FilePath(Path);
574 FixupRelativePath(FilePath);
575
576 llvm::ErrorOr<llvm::vfs::Status> S = FS->status(FilePath.c_str());
577 if (!S)
578 return S.getError();
579 Result = *S;
580 return std::error_code();
581 }
582
GetUniqueIDMapping(SmallVectorImpl<const FileEntry * > & UIDToFiles) const583 void FileManager::GetUniqueIDMapping(
584 SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
585 UIDToFiles.clear();
586 UIDToFiles.resize(NextFileUID);
587
588 // Map file entries
589 for (llvm::StringMap<llvm::ErrorOr<FileEntryRef::MapValue>,
590 llvm::BumpPtrAllocator>::const_iterator
591 FE = SeenFileEntries.begin(),
592 FEEnd = SeenFileEntries.end();
593 FE != FEEnd; ++FE)
594 if (llvm::ErrorOr<FileEntryRef::MapValue> Entry = FE->getValue()) {
595 if (const auto *FE = Entry->V.dyn_cast<FileEntry *>())
596 UIDToFiles[FE->getUID()] = FE;
597 }
598
599 // Map virtual file entries
600 for (const auto &VFE : VirtualFileEntries)
601 UIDToFiles[VFE->getUID()] = VFE.get();
602 }
603
getCanonicalName(const DirectoryEntry * Dir)604 StringRef FileManager::getCanonicalName(const DirectoryEntry *Dir) {
605 llvm::DenseMap<const void *, llvm::StringRef>::iterator Known
606 = CanonicalNames.find(Dir);
607 if (Known != CanonicalNames.end())
608 return Known->second;
609
610 StringRef CanonicalName(Dir->getName());
611
612 SmallString<4096> CanonicalNameBuf;
613 if (!FS->getRealPath(Dir->getName(), CanonicalNameBuf))
614 CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
615
616 CanonicalNames.insert({Dir, CanonicalName});
617 return CanonicalName;
618 }
619
getCanonicalName(const FileEntry * File)620 StringRef FileManager::getCanonicalName(const FileEntry *File) {
621 llvm::DenseMap<const void *, llvm::StringRef>::iterator Known
622 = CanonicalNames.find(File);
623 if (Known != CanonicalNames.end())
624 return Known->second;
625
626 StringRef CanonicalName(File->getName());
627
628 SmallString<4096> CanonicalNameBuf;
629 if (!FS->getRealPath(File->getName(), CanonicalNameBuf))
630 CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
631
632 CanonicalNames.insert({File, CanonicalName});
633 return CanonicalName;
634 }
635
PrintStats() const636 void FileManager::PrintStats() const {
637 llvm::errs() << "\n*** File Manager Stats:\n";
638 llvm::errs() << UniqueRealFiles.size() << " real files found, "
639 << UniqueRealDirs.size() << " real dirs found.\n";
640 llvm::errs() << VirtualFileEntries.size() << " virtual files found, "
641 << VirtualDirectoryEntries.size() << " virtual dirs found.\n";
642 llvm::errs() << NumDirLookups << " dir lookups, "
643 << NumDirCacheMisses << " dir cache misses.\n";
644 llvm::errs() << NumFileLookups << " file lookups, "
645 << NumFileCacheMisses << " file cache misses.\n";
646
647 //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;
648 }
649