Function bthread_id_unlock

src/bthread/id.cpp:567–607

}

int bthread_id_unlock(bthread_id_t id) {
    bthread::Id* const meta = address_resource(bthread::get_slot(id));
    if (!meta) {
        return EINVAL;
    }
    uint32_t* butex = meta->butex;
    // Release fence makes sure all changes made before signal visible to
    // woken-up waiters.
    const uint32_t id_ver = bthread::get_version(id);
    meta->mutex.lock();
    if (!meta->has_version(id_ver)) {
        meta->mutex.unlock();
        LOG(FATAL) << "Invalid bthread_id=" << id.value;
        return EINVAL;
    }
    if (*butex == meta->first_ver) {
        meta->mutex.unlock();
        LOG(FATAL) << "bthread_id=" << id.value << " is not locked!";
        return EPERM;
    }
    bthread::PendingError front;
    if (meta->pending_q.pop(&front)) {
        meta->lock_location = front.location;
        meta->mutex.unlock();
        if (meta->on_error) {
            return meta->on_error(front.id, meta->data, front.error_code);
        } else {
            return meta->on_error2(front.id, meta->data, front.error_code,
                                   front.error_text);
        }
    } else {
        const bool contended = (*butex == meta->contended_ver());
        *butex = meta->first_ver;
        meta->mutex.unlock();
        if (contended) {
            // We may wake up already-reused id, but that's OK.
            bthread::butex_wake(butex);
        }
        return 0; 
    }
}

int bthread_id_unlock_and_destroy(bthread_id_t id) {
    bthread::Id* const meta = address_resource(bthread::get_slot(id));