Author: ioeric Date: Wed Sep 5 02:45:27 2018 New Revision: 341455 URL: http://llvm.org/viewvc/llvm-project?rev=341455&view=rev Log: [VFS] Cache the current working directory for the real FS.
Reviewers: sammccall Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D51641 Modified: cfe/trunk/lib/Basic/VirtualFileSystem.cpp Modified: cfe/trunk/lib/Basic/VirtualFileSystem.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/VirtualFileSystem.cpp?rev=341455&r1=341454&r2=341455&view=diff ============================================================================== --- cfe/trunk/lib/Basic/VirtualFileSystem.cpp (original) +++ cfe/trunk/lib/Basic/VirtualFileSystem.cpp Wed Sep 5 02:45:27 2018 @@ -49,6 +49,7 @@ #include <limits> #include <map> #include <memory> +#include <mutex> #include <string> #include <system_error> #include <utility> @@ -244,6 +245,9 @@ public: std::error_code setCurrentWorkingDirectory(const Twine &Path) override; std::error_code getRealPath(const Twine &Path, SmallVectorImpl<char> &Output) const override; +private: + mutable std::mutex CWDMutex; + mutable std::string CWDCache; }; } // namespace @@ -266,10 +270,14 @@ RealFileSystem::openFileForRead(const Tw } llvm::ErrorOr<std::string> RealFileSystem::getCurrentWorkingDirectory() const { + std::lock_guard<std::mutex> Lock(CWDMutex); + if (!CWDCache.empty()) + return CWDCache; SmallString<256> Dir; if (std::error_code EC = llvm::sys::fs::current_path(Dir)) return EC; - return Dir.str().str(); + CWDCache = Dir.str(); + return CWDCache; } std::error_code RealFileSystem::setCurrentWorkingDirectory(const Twine &Path) { @@ -280,7 +288,13 @@ std::error_code RealFileSystem::setCurre // difference for example on network filesystems, where symlinks might be // switched during runtime of the tool. Fixing this depends on having a // file system abstraction that allows openat() style interactions. - return llvm::sys::fs::set_current_path(Path); + if (auto EC = llvm::sys::fs::set_current_path(Path)) + return EC; + + // Invalidate cache. + std::lock_guard<std::mutex> Lock(CWDMutex); + CWDCache.clear(); + return std::error_code(); } std::error_code _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
