+static std::error_code createUniqueEntity(const Twine &Model, int &ResultFD,
+ SmallVectorImpl<char> &ResultPath,
+ bool MakeAbsolute, unsigned Mode,
+ FSEntity Type) {
+ SmallString<128> ModelStorage;
+ Model.toVector(ModelStorage);
+
+ if (MakeAbsolute) {
+ // Make model absolute by prepending a temp directory if it's not already.
+ if (!sys::path::is_absolute(Twine(ModelStorage))) {
+ SmallString<128> TDir;
+ sys::path::system_temp_directory(true, TDir);
+ sys::path::append(TDir, Twine(ModelStorage));
+ ModelStorage.swap(TDir);
+ }
+ }
+
+ // From here on, DO NOT modify model. It may be needed if the randomly chosen
+ // path already exists.
+ ResultPath = ModelStorage;
+ // Null terminate.
+ ResultPath.push_back(0);
+ ResultPath.pop_back();
+
+retry_random_path:
+ // Replace '%' with random chars.
+ for (unsigned i = 0, e = ModelStorage.size(); i != e; ++i) {
+ if (ModelStorage[i] == '%')
+ ResultPath[i] = "0123456789abcdef"[sys::Process::GetRandomNumber() & 15];
+ }
+
+ // Try to open + create the file.
+ switch (Type) {
+ case FS_File: {
+ if (std::error_code EC =
+ sys::fs::openFileForWrite(Twine(ResultPath.begin()), ResultFD,
+ sys::fs::F_RW | sys::fs::F_Excl, Mode)) {
+ if (EC == errc::file_exists)
+ goto retry_random_path;
+ return EC;
+ }
+
+ return std::error_code();
+ }
+
+ case FS_Name: {
+ std::error_code EC =
+ sys::fs::access(ResultPath.begin(), sys::fs::AccessMode::Exist);
+ if (EC == errc::no_such_file_or_directory)
+ return std::error_code();
+ if (EC)
+ return EC;
+ goto retry_random_path;
+ }
+
+ case FS_Dir: {
+ if (std::error_code EC =
+ sys::fs::create_directory(ResultPath.begin(), false)) {
+ if (EC == errc::file_exists)
+ goto retry_random_path;
+ return EC;
+ }
+ return std::error_code();
+ }
+ }
+ llvm_unreachable("Invalid Type");
+}