Function id_create_impl

src/bthread/id.cpp:325–349

const int ID_MAX_RANGE = 1024;

static int id_create_impl(
    bthread_id_t* id, void* data,
    int (*on_error)(bthread_id_t, void*, int),
    int (*on_error2)(bthread_id_t, void*, int, const std::string&)) {
    IdResourceId slot;
    Id* const meta = get_resource(&slot);
    if (meta) {
        meta->data = data;
        meta->on_error = on_error;
        meta->on_error2 = on_error2;
        CHECK(meta->pending_q.empty());
        uint32_t* butex = meta->butex;
        if (0 == *butex || *butex + ID_MAX_RANGE + 2 < *butex) {
            // Skip 0 so that bthread_id_t is never 0
            // avoid overflow to make comparisons simpler.
            *butex = 1;
        }
        *meta->join_butex = *butex;
        meta->first_ver = *butex;
        meta->locked_ver = *butex + 1;
        *id = make_id(*butex, slot);
        return 0;
    }
    return ENOMEM;
}

static int id_create_ranged_impl(
    bthread_id_t* id, void* data,