[boost] Re: Smart Pointers - mutexing

From: Kevlin Henney (Kevlin.Henney_at_[hidden])
Date: 2000-01-07 02:33:33

>>   mutexed(const mutexed& from) :
>>        lock(0),
>>        value()
>>        {
>>          from.lock.acquire_lock();
>>          this->value = from.value;
>>          from.lock.release_lock();
>>          // or, use constructor locking, if you want locks released on
exceptions
>>        }
>
>This should use member initialisation, not assignment, ie
>
>     mutexed(const mutexed& from)
>       : lock(0), value((from.acquire_lock(), from.value))
>     {
>         from.release_lock();
>     }

On rereading this, I realise that it's not exception safe. Here's the fix:

     mutexed(const mutexed& from)
       : lock(0), value((lock_acquirer(from.lock), from.value))
     {
     }

Kevlin