// Copyright 2017 The Abseil Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #ifndef ABSL_BASE_INTERNAL_ERRNO_SAVER_H_ #define ABSL_BASE_INTERNAL_ERRNO_SAVER_H_ #include <cerrno> #include "absl/base/config.h" namespace absl { ABSL_NAMESPACE_BEGIN namespace base_internal { // `ErrnoSaver` captures the value of `errno` upon construction and restores it // upon deletion. It is used in low-level code and must be super fast. Do not // add instrumentation, even in debug modes. class ErrnoSaver { public: ErrnoSaver() : saved_errno_(errno) {} ~ErrnoSaver() { errno = saved_errno_; } int operator()() const { return saved_errno_; } private: const int saved_errno_; }; } // namespace base_internal ABSL_NAMESPACE_END } // namespace absl #endif // ABSL_BASE_INTERNAL_ERRNO_SAVER_H_