• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef LIBMEMUNREACHABLE_SCOPED_ALARM_H_
18 #define LIBMEMUNREACHABLE_SCOPED_ALARM_H_
19 
20 #include <signal.h>
21 #include <sys/time.h>
22 
23 #include <chrono>
24 #include <functional>
25 
26 namespace android {
27 
28 class ScopedAlarm {
29  public:
ScopedAlarm(std::chrono::microseconds us,std::function<void ()> func)30   ScopedAlarm(std::chrono::microseconds us, std::function<void()> func) {
31     func_ = func;
32     struct sigaction act {};
33     act.sa_handler = [](int) { ScopedAlarm::func_(); };
34     sigaction(SIGALRM, &act, &old_act_);
35 
36     std::chrono::seconds s = std::chrono::duration_cast<std::chrono::seconds>(us);
37     itimerval t = itimerval{};
38     t.it_value.tv_sec = s.count();
39     t.it_value.tv_usec = (us - s).count();
40     setitimer(ITIMER_REAL, &t, NULL);
41   }
~ScopedAlarm()42   ~ScopedAlarm() {
43     itimerval t = itimerval{};
44     setitimer(ITIMER_REAL, &t, NULL);
45     sigaction(SIGALRM, &old_act_, NULL);
46   }
47 
48  private:
49   static std::function<void()> func_;
50   struct sigaction old_act_;
51 };
52 
53 }  // namespace android
54 
55 #endif
56