1 //===--- FileSystemStatCache.cpp - Caching for 'stat' calls ---------------===// 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 defines the FileSystemStatCache interface. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "clang/Basic/FileSystemStatCache.h" 15 #include "llvm/System/Path.h" 16 using namespace clang; 17 18 #if defined(_MSC_VER) 19 #define S_ISDIR(s) (_S_IFDIR & s) 20 #endif 21 22 MemorizeStatCalls::LookupResult 23 MemorizeStatCalls::getStat(const char *Path, struct stat &StatBuf) { 24 LookupResult Result = statChained(Path, StatBuf); 25 26 // Do not cache failed stats, it is easy to construct common inconsistent 27 // situations if we do, and they are not important for PCH performance (which 28 // currently only needs the stats to construct the initial FileManager 29 // entries). 30 if (Result == CacheMissing) 31 return Result; 32 33 // Cache file 'stat' results and directories with absolutely paths. 34 if (!S_ISDIR(StatBuf.st_mode) || llvm::sys::Path(Path).isAbsolute()) 35 StatCalls[Path] = StatBuf; 36 37 return Result; 38 } 39