Function bthread_setspecific

src/bthread/key.cpp:626–648

NOTE: Can't borrow_keytable in bthread_setspecific, otherwise following memory leak may occur: -> bthread_getspecific fails to borrow_keytable and returns NULL. -> bthread_setspecific succeeds to borrow_keytable and overwrites old data at the position with newly created data, the old data is leaked.

//  -> bthread_setspecific succeeds to borrow_keytable and overwrites old data
//     at the position with newly created data, the old data is leaked.
int bthread_setspecific(bthread_key_t key, void* data) {
    bthread::KeyTable* kt = bthread::tls_bls.keytable;
    if (NULL == kt) {
        kt = new (std::nothrow) bthread::KeyTable;
        if (NULL == kt) {
            return ENOMEM;
        }
        bthread::tls_bls.keytable = kt;
        bthread::TaskGroup* const g = bthread::BAIDU_GET_VOLATILE_THREAD_LOCAL(tls_task_group);
        if (g) {
            g->current_task()->local_storage.keytable = kt;
        } else {
            // Only cleanup keytable created by pthread.
            // keytable created by bthread will be deleted
            // in `return_keytable' or `bthread_keytable_pool_destroy'.
            if (!bthread::tls_ever_created_keytable) {
                bthread::tls_ever_created_keytable = true;
                CHECK_EQ(0, butil::thread_atexit(bthread::cleanup_pthread, kt));
            }
        }
    }
    return kt->set_data(key, data);
}

void* bthread_getspecific(bthread_key_t key) {
    bthread::KeyTable* kt = bthread::tls_bls.keytable;