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