Le 20/02/13 03:08, Gabriel Bizzotto a écrit :

> My class allows in addition to lock several synchronized values using
the deadlock free lock algorithm as e.g.

I did not understand the unique_synchronize part, though.

synchronize() returns a strict_lock_ptr which is something like a lock_guard that is not Lockable.
unique_synchronize() returns a unique_lock_ptr which is something like a unique_lock (Lockable) and can be used with dead-lock free algorithms. This facility can be used when locking several synchronized_value instances to avoid dead-lock.

this dead-lock algorithm is used e.g. to define the assignment operation as follows

    synchronized_value& operator=(synchronized_value const& rhs)
    {
      if(&rhs != this)
      {
        unique_lock<lockable_type> lk1(mtx_, defer_lock);
        unique_lock<lockable_type> lk2(rhs.mtx_, defer_lock);
        lock(lk1,lk2);

        value_ = rhs.value_;
      }
      return *this;
    }

so that

//thread1
a=b
// thread2
b=a

will not dead-lock.

Best,
Vicente