xref: /aosp_15_r20/external/libchrome/base/scoped_clear_errno.h (revision 635a864187cb8b6c713ff48b7e790a6b21769273)
1*635a8641SAndroid Build Coastguard Worker // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2*635a8641SAndroid Build Coastguard Worker // Use of this source code is governed by a BSD-style license that can be
3*635a8641SAndroid Build Coastguard Worker // found in the LICENSE file.
4*635a8641SAndroid Build Coastguard Worker 
5*635a8641SAndroid Build Coastguard Worker #ifndef BASE_SCOPED_CLEAR_ERRNO_H_
6*635a8641SAndroid Build Coastguard Worker #define BASE_SCOPED_CLEAR_ERRNO_H_
7*635a8641SAndroid Build Coastguard Worker 
8*635a8641SAndroid Build Coastguard Worker #include <errno.h>
9*635a8641SAndroid Build Coastguard Worker 
10*635a8641SAndroid Build Coastguard Worker #include "base/macros.h"
11*635a8641SAndroid Build Coastguard Worker 
12*635a8641SAndroid Build Coastguard Worker namespace base {
13*635a8641SAndroid Build Coastguard Worker 
14*635a8641SAndroid Build Coastguard Worker // Simple scoper that saves the current value of errno, resets it to 0, and on
15*635a8641SAndroid Build Coastguard Worker // destruction puts the old value back.
16*635a8641SAndroid Build Coastguard Worker class ScopedClearErrno {
17*635a8641SAndroid Build Coastguard Worker  public:
ScopedClearErrno()18*635a8641SAndroid Build Coastguard Worker   ScopedClearErrno() : old_errno_(errno) {
19*635a8641SAndroid Build Coastguard Worker     errno = 0;
20*635a8641SAndroid Build Coastguard Worker   }
~ScopedClearErrno()21*635a8641SAndroid Build Coastguard Worker   ~ScopedClearErrno() {
22*635a8641SAndroid Build Coastguard Worker     if (errno == 0)
23*635a8641SAndroid Build Coastguard Worker       errno = old_errno_;
24*635a8641SAndroid Build Coastguard Worker   }
25*635a8641SAndroid Build Coastguard Worker 
26*635a8641SAndroid Build Coastguard Worker  private:
27*635a8641SAndroid Build Coastguard Worker   const int old_errno_;
28*635a8641SAndroid Build Coastguard Worker 
29*635a8641SAndroid Build Coastguard Worker   DISALLOW_COPY_AND_ASSIGN(ScopedClearErrno);
30*635a8641SAndroid Build Coastguard Worker };
31*635a8641SAndroid Build Coastguard Worker 
32*635a8641SAndroid Build Coastguard Worker }  // namespace base
33*635a8641SAndroid Build Coastguard Worker 
34*635a8641SAndroid Build Coastguard Worker #endif  // BASE_SCOPED_CLEAR_ERRNO_H_
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