---

#include <systemd/sd-bus.h>

int ListActiveInstances(sd_bus *bus, std::vector<LiveInstance> *out) {
    sd_bus_error err = SD_BUS_ERROR_NULL;
    sd_bus_message *m = nullptr, *reply = nullptr;
    int r;

    r = sd_bus_message_new_method_call(
            bus, &m,
            "org.freedesktop.systemd1",
            "/org/freedesktop/systemd1",
            "org.freedesktop.systemd1.Manager",
            "ListUnitsByPatterns");
    if (r < 0) goto finish;

    // in: as states
    r = sd_bus_message_append_strv(m, (char *[]){ (char*)"active", nullptr });
    if (r < 0) goto finish;
    // in: as patterns
    r = sd_bus_message_append_strv(m, (char *[]){ (char*)"osmo-gbproxy@*.service", nullptr });
    if (r < 0) goto finish;

    r = sd_bus_call(bus, m, 0, &err, &reply);
    if (r < 0) goto finish;

    // out: a(ssssssouso)
    r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssssouso)");
    if (r < 0) goto finish;

    for (;;) {
        const char *name, *desc, *load, *active, *sub, *followed;
        const char *unit_path, *job_type, *job_path;
        uint32_t job_id;

        r = sd_bus_message_read(reply, "(ssssssouso)",
                                &name, &desc, &load, &active, &sub, &followed,
                                &unit_path, &job_id, &job_type, &job_path);
        if (r < 0) goto finish;
        if (r == 0) break;                 // конец массива

        LiveInstance li;
        if (ParseUnitName(name, &li)) {
            out->push_back(std::move(li));
        } else {
            spdlog::warn("unparsable unit name, skipped: {}", name);
        }
    }

    r = sd_bus_message_exit_container(reply);

finish:
    sd_bus_error_free(&err);
    sd_bus_message_unref(m);
    sd_bus_message_unref(reply);
    return r;
}