Files
concurrency-in-action/source/listing_7.6.cpp
2014-04-22 21:54:16 -04:00

37 lines
820 B
C++

#include <atomic>
#include <memory>
std::shared_ptr<T> pop()
{
std::atomic<void*>& hp=get_hazard_pointer_for_current_thread();
node* old_head=head.load();
do
{
node* temp;
do
{
temp=old_head;
hp.store(old_head);
old_head=head.load();
} while(old_head!=temp);
}
while(old_head &&
!head.compare_exchange_strong(old_head,old_head->next));
hp.store(nullptr);
std::shared_ptr<T> res;
if(old_head)
{
res.swap(old_head->data);
if(outstanding_hazard_pointers_for(old_head))
{
reclaim_later(old_head);
}
else
{
delete old_head;
}
delete_nodes_with_no_hazards();
}
return res;
}