diff options
Diffstat (limited to 'third_party/abseil_cpp/absl/base/internal/errno_saver.h')
-rw-r--r-- | third_party/abseil_cpp/absl/base/internal/errno_saver.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/errno_saver.h b/third_party/abseil_cpp/absl/base/internal/errno_saver.h new file mode 100644 index 000000000000..251de510fc93 --- /dev/null +++ b/third_party/abseil_cpp/absl/base/internal/errno_saver.h @@ -0,0 +1,43 @@ +// 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_ |