src/reverselock.h

   1 // Copyright (c) 2015-2016 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #ifndef BITCOIN_REVERSELOCK_H
   6 #define BITCOIN_REVERSELOCK_H
   7
   8 /**
   9  * An RAII-style reverse lock. Unlocks on construction and locks on destruction.
  10  */
  11 template<typename Lock>
  12 class reverse_lock
  13 {
  14 public:
  15
  16     explicit reverse_lock(Lock& _lock) : lock(_lock) {
  17         _lock.unlock();
  18         _lock.swap(templock);
  19     }
  20
  21     ~reverse_lock() {
  22         templock.lock();
  23         templock.swap(lock);
  24     }
  25
  26 private:
  27     reverse_lock(reverse_lock const&);
  28     reverse_lock& operator=(reverse_lock const&);
  29
  30     Lock& lock;
  31     Lock templock;
  32 };
  33
  34 #endif // BITCOIN_REVERSELOCK_H