Matt Hurd wrote:
Yes, that is the classic solution but it never strikes me as quite what I need.
I've been struggling to find a cute solution I'm happy with. Mainly because I also typically want to expose the foo1_impl() for the cases when I wish to lock externally for multiple operations.
Andrei Alexandrescu's suggestion is to make foo1_impl take a lock: void foo1() { scoped_lock<> lock(mx_); foo1( lock ); } void foo1( scoped_lock<> & l ) { assert( l.locked() ); assert( l.mutex() == &mx_ ); // or not, to allow ext. sync // do things, incl. foo2( l ); } This doesn't solve the boilerplate problem, though. Maybe something like void foo1( scoped_lock<> * pl = 0 ) { assert( pl == 0 || pl->locked() ); scoped_lock<> internal_lock( mx_, pl == 0 ); if( pl == 0 ) pl = &internal_lock; // do things, incl. foo2( pl ); } where the boilerplate can be hidden in a class.