Files
concurrency-in-action/source/listing_7.6.cpp
2018-10-18 00:40:34 -05:00

31 lines
707 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;
}