Method getTaskAndRegister

src/common/task_system/task_scheduler.cpp:179–203

}

std::shared_ptr<ScheduledTask> TaskScheduler::getTaskAndRegister() {
    if (taskQueue.empty()) {
        return nullptr;
    }
    auto it = taskQueue.begin();
    while (it != taskQueue.end()) {
        auto task = (*it)->task;
        if (!task->registerThread()) {
            // If we cannot register for a thread it is because of three possibilities:
            // (i) maximum number of threads have registered for task and the task is completed
            // without an exception; or (ii) same as (i) but the task has not yet successfully
            // completed; or (iii) task has an exception; Only in (i) we remove the task from the
            // queue. For (ii) and (iii) we keep the task in queue. Recall erroring tasks need to be
            // manually removed.
            if (task->isCompletedSuccessfully()) { // option (i)
                it = taskQueue.erase(it);
            } else { // option (ii) or (iii): keep the task in the queue.
                ++it;
            }
        } else {
            return *it;
        }
    }
    return nullptr;
}

void TaskScheduler::removeErroringTask(uint64_t scheduledTaskID) {
    lock_t lck{taskSchedulerMtx};