xref: /aosp_15_r20/system/libbase/include/android-base/errno_restorer.h (revision 8f0ba417480079999ba552f1087ae592091b9d02)
1*8f0ba417SAndroid Build Coastguard Worker /*
2*8f0ba417SAndroid Build Coastguard Worker  * Copyright (C) 2020 The Android Open Source Project
3*8f0ba417SAndroid Build Coastguard Worker  *
4*8f0ba417SAndroid Build Coastguard Worker  * Licensed under the Apache License, Version 2.0 (the "License");
5*8f0ba417SAndroid Build Coastguard Worker  * you may not use this file except in compliance with the License.
6*8f0ba417SAndroid Build Coastguard Worker  * You may obtain a copy of the License at
7*8f0ba417SAndroid Build Coastguard Worker  *
8*8f0ba417SAndroid Build Coastguard Worker  *      http://www.apache.org/licenses/LICENSE-2.0
9*8f0ba417SAndroid Build Coastguard Worker  *
10*8f0ba417SAndroid Build Coastguard Worker  * Unless required by applicable law or agreed to in writing, software
11*8f0ba417SAndroid Build Coastguard Worker  * distributed under the License is distributed on an "AS IS" BASIS,
12*8f0ba417SAndroid Build Coastguard Worker  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13*8f0ba417SAndroid Build Coastguard Worker  * See the License for the specific language governing permissions and
14*8f0ba417SAndroid Build Coastguard Worker  * limitations under the License.
15*8f0ba417SAndroid Build Coastguard Worker  */
16*8f0ba417SAndroid Build Coastguard Worker 
17*8f0ba417SAndroid Build Coastguard Worker #pragma once
18*8f0ba417SAndroid Build Coastguard Worker 
19*8f0ba417SAndroid Build Coastguard Worker #include "errno.h"
20*8f0ba417SAndroid Build Coastguard Worker 
21*8f0ba417SAndroid Build Coastguard Worker #include "android-base/macros.h"
22*8f0ba417SAndroid Build Coastguard Worker 
23*8f0ba417SAndroid Build Coastguard Worker namespace android {
24*8f0ba417SAndroid Build Coastguard Worker namespace base {
25*8f0ba417SAndroid Build Coastguard Worker 
26*8f0ba417SAndroid Build Coastguard Worker class ErrnoRestorer {
27*8f0ba417SAndroid Build Coastguard Worker  public:
ErrnoRestorer()28*8f0ba417SAndroid Build Coastguard Worker   ErrnoRestorer() : saved_errno_(errno) {}
29*8f0ba417SAndroid Build Coastguard Worker 
~ErrnoRestorer()30*8f0ba417SAndroid Build Coastguard Worker   ~ErrnoRestorer() { errno = saved_errno_; }
31*8f0ba417SAndroid Build Coastguard Worker 
32*8f0ba417SAndroid Build Coastguard Worker   // Allow this object to be used as part of && operation.
33*8f0ba417SAndroid Build Coastguard Worker   explicit operator bool() const { return true; }
34*8f0ba417SAndroid Build Coastguard Worker 
35*8f0ba417SAndroid Build Coastguard Worker  private:
36*8f0ba417SAndroid Build Coastguard Worker   const int saved_errno_;
37*8f0ba417SAndroid Build Coastguard Worker 
38*8f0ba417SAndroid Build Coastguard Worker   DISALLOW_COPY_AND_ASSIGN(ErrnoRestorer);
39*8f0ba417SAndroid Build Coastguard Worker };
40*8f0ba417SAndroid Build Coastguard Worker 
41*8f0ba417SAndroid Build Coastguard Worker }  // namespace base
42*8f0ba417SAndroid Build Coastguard Worker }  // namespace android
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