110e286aa8d39fb51a21412850265d9dae74613eeChris Lattner//===--- FileSystemStatCache.cpp - Caching for 'stat' calls ---------------===// 210e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// 310e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// The LLVM Compiler Infrastructure 410e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// 510e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// This file is distributed under the University of Illinois Open Source 610e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// License. See LICENSE.TXT for details. 710e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// 810e286aa8d39fb51a21412850265d9dae74613eeChris Lattner//===----------------------------------------------------------------------===// 910e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// 1010e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// This file defines the FileSystemStatCache interface. 1110e286aa8d39fb51a21412850265d9dae74613eeChris Lattner// 1210e286aa8d39fb51a21412850265d9dae74613eeChris Lattner//===----------------------------------------------------------------------===// 1310e286aa8d39fb51a21412850265d9dae74613eeChris Lattner 1410e286aa8d39fb51a21412850265d9dae74613eeChris Lattner#include "clang/Basic/FileSystemStatCache.h" 15651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "clang/Basic/VirtualFileSystem.h" 1603013fa9a0bf1ef4b907f5fec006c8f4000fdd21Michael J. Spencer#include "llvm/Support/Path.h" 17b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner 18b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner// FIXME: This is terrible, we need this for ::close. 19b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#if !defined(_MSC_VER) && !defined(__MINGW32__) 20b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#include <unistd.h> 21b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#include <sys/uio.h> 22b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#else 23b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#include <io.h> 24b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner#endif 2510e286aa8d39fb51a21412850265d9dae74613eeChris Lattnerusing namespace clang; 2610e286aa8d39fb51a21412850265d9dae74613eeChris Lattner 2772f6130a17742e9c9078b4b60ad8f7ac2c690a3bChris Lattner#if defined(_MSC_VER) 280d4739abf60372abdbafabd8ed59acc5d01729b5Francois Pichet#define S_ISDIR(s) ((_S_IFDIR & s) !=0) 2972f6130a17742e9c9078b4b60ad8f7ac2c690a3bChris Lattner#endif 3072f6130a17742e9c9078b4b60ad8f7ac2c690a3bChris Lattner 3199ba9e3bd70671f3441fb974895f226a83ce0e66David Blaikievoid FileSystemStatCache::anchor() { } 3299ba9e3bd70671f3441fb974895f226a83ce0e66David Blaikie 33651f13cea278ec967336033dd032faef0e9fc2ecStephen Hinesstatic void copyStatusToFileData(const vfs::Status &Status, 340fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola FileData &Data) { 35651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines Data.Name = Status.getName(); 360fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola Data.Size = Status.getSize(); 370fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola Data.ModTime = Status.getLastModificationTime().toEpochTime(); 380fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola Data.UniqueID = Status.getUniqueID(); 39651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines Data.IsDirectory = Status.isDirectory(); 40651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines Data.IsNamedPipe = Status.getType() == llvm::sys::fs::file_type::fifo_file; 410fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola Data.InPCH = false; 426bcf27bb9a4b5c3f79cb44c0e4654a6d7619ad89Stephen Hines Data.IsVFSMapped = Status.IsVFSMapped; 430fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola} 440fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola 45898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// FileSystemStatCache::get - Get the 'stat' information for the specified 46c0f31fd08537b65ad92db8ce860747e3402a07e6Chris Lattner/// path, using the cache to accelerate it if possible. This returns true if 47898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// the path does not exist or false if it exists. 48898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// 49e5d30e3b403539b10aaa52f03875a2243bf88904Argyrios Kyrtzidis/// If isFile is true, then this lookup should only return success for files 50e5d30e3b403539b10aaa52f03875a2243bf88904Argyrios Kyrtzidis/// (not directories). If it is false this lookup should only return 51898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// success for directories (not files). On a successful file lookup, the 52898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// implementation can optionally fill in FileDescriptor with a valid 53898a061f69e1145bf89a987c08203132b9922a3cChris Lattner/// descriptor and the client guarantees that it will close it. 540fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindolabool FileSystemStatCache::get(const char *Path, FileData &Data, bool isFile, 55ef8225444452a1486bd721f3285301fe84643b00Stephen Hines std::unique_ptr<vfs::File> *F, 56ef8225444452a1486bd721f3285301fe84643b00Stephen Hines FileSystemStatCache *Cache, vfs::FileSystem &FS) { 57898a061f69e1145bf89a987c08203132b9922a3cChris Lattner LookupResult R; 58e5d30e3b403539b10aaa52f03875a2243bf88904Argyrios Kyrtzidis bool isForDir = !isFile; 595cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner 605cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // If we have a cache, use it to resolve the stat query. 61898a061f69e1145bf89a987c08203132b9922a3cChris Lattner if (Cache) 62651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines R = Cache->getStat(Path, Data, isFile, F, FS); 63651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines else if (isForDir || !F) { 64e5d30e3b403539b10aaa52f03875a2243bf88904Argyrios Kyrtzidis // If this is a directory or a file descriptor is not needed and we have 65e5d30e3b403539b10aaa52f03875a2243bf88904Argyrios Kyrtzidis // no cache, just go to the file system. 66651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines llvm::ErrorOr<vfs::Status> Status = FS.status(Path); 67651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines if (!Status) { 680fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola R = CacheMissing; 690fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola } else { 700fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola R = CacheExists; 71651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines copyStatusToFileData(*Status, Data); 720fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola } 735cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner } else { 745cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // Otherwise, we have to go to the filesystem. We can always just use 755cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // 'stat' here, but (for files) the client is asking whether the file exists 765cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // because it wants to turn around and *open* it. It is more efficient to 775cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // do "open+fstat" on success than it is to do "stat+open". 785cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // 795cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // Because of this, check to see if the file exists with 'open'. If the 805cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // open succeeds, use fstat to get the stat info. 81651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines std::unique_ptr<vfs::File> OwnedFile; 82ef8225444452a1486bd721f3285301fe84643b00Stephen Hines std::error_code EC = FS.openFileForRead(Path, OwnedFile); 83d965f95daa97097c8ddc5e1165ceae585a888719Rafael Espindola 84d965f95daa97097c8ddc5e1165ceae585a888719Rafael Espindola if (EC) { 855cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // If the open fails, our "stat" fails. 865cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner R = CacheMissing; 875cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner } else { 885cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // Otherwise, the open succeeded. Do an fstat to get the information 895cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // about the file. We'll end up returning the open file descriptor to the 905cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // client to do what they please with it. 91651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines llvm::ErrorOr<vfs::Status> Status = OwnedFile->status(); 92651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines if (Status) { 935cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner R = CacheExists; 94651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines copyStatusToFileData(*Status, Data); 95ef8225444452a1486bd721f3285301fe84643b00Stephen Hines *F = std::move(OwnedFile); 960fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola } else { 975cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // fstat rarely fails. If it does, claim the initial open didn't 985cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner // succeed. 995cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner R = CacheMissing; 1006bcf27bb9a4b5c3f79cb44c0e4654a6d7619ad89Stephen Hines *F = nullptr; 1015cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner } 1025cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner } 1035cc1c738b0c51af55cbfe7672c284c19f8e30eb2Chris Lattner } 104898a061f69e1145bf89a987c08203132b9922a3cChris Lattner 105b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner // If the path doesn't exist, return failure. 106898a061f69e1145bf89a987c08203132b9922a3cChris Lattner if (R == CacheMissing) return true; 107898a061f69e1145bf89a987c08203132b9922a3cChris Lattner 108b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner // If the path exists, make sure that its "directoryness" matches the clients 109b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner // demands. 1100fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola if (Data.IsDirectory != isForDir) { 111b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner // If not, close the file if opened. 112ef8225444452a1486bd721f3285301fe84643b00Stephen Hines if (F) 1136bcf27bb9a4b5c3f79cb44c0e4654a6d7619ad89Stephen Hines *F = nullptr; 114b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner 115b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner return true; 116b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner } 117b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner 118b2b93c12d768cfdeb21909f734b04ccb82d75da2Chris Lattner return false; 119898a061f69e1145bf89a987c08203132b9922a3cChris Lattner} 120898a061f69e1145bf89a987c08203132b9922a3cChris Lattner 12110e286aa8d39fb51a21412850265d9dae74613eeChris LattnerMemorizeStatCalls::LookupResult 1220fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael EspindolaMemorizeStatCalls::getStat(const char *Path, FileData &Data, bool isFile, 123ef8225444452a1486bd721f3285301fe84643b00Stephen Hines std::unique_ptr<vfs::File> *F, vfs::FileSystem &FS) { 124651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines LookupResult Result = statChained(Path, Data, isFile, F, FS); 1250fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola 12610e286aa8d39fb51a21412850265d9dae74613eeChris Lattner // Do not cache failed stats, it is easy to construct common inconsistent 12710e286aa8d39fb51a21412850265d9dae74613eeChris Lattner // situations if we do, and they are not important for PCH performance (which 12810e286aa8d39fb51a21412850265d9dae74613eeChris Lattner // currently only needs the stats to construct the initial FileManager 12910e286aa8d39fb51a21412850265d9dae74613eeChris Lattner // entries). 130d6f611198089b78e32d3a15fe8bc986204aee1aaChris Lattner if (Result == CacheMissing) 13110e286aa8d39fb51a21412850265d9dae74613eeChris Lattner return Result; 13210e286aa8d39fb51a21412850265d9dae74613eeChris Lattner 13310e286aa8d39fb51a21412850265d9dae74613eeChris Lattner // Cache file 'stat' results and directories with absolutely paths. 1340fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola if (!Data.IsDirectory || llvm::sys::path::is_absolute(Path)) 1350fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola StatCalls[Path] = Data; 1360fda0f75f053ad9afdb2bb8d4ea72c5e6a49d657Rafael Espindola 13710e286aa8d39fb51a21412850265d9dae74613eeChris Lattner return Result; 13810e286aa8d39fb51a21412850265d9dae74613eeChris Lattner} 139