Program Listing for File subscriber_available.hpp

            

            
/*
* SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

#ifndef HOLOSCAN_PUBSUB_RUNTIME_CONDITIONS_SUBSCRIBER_AVAILABLE_HPP
#define HOLOSCAN_PUBSUB_RUNTIME_CONDITIONS_SUBSCRIBER_AVAILABLE_HPP

#include <atomic>
#include <cstdint>
#include <memory>

#include <holoscan/core/condition.hpp>
#include <holoscan/core/resources/gxf/pubsub_transmitter.hpp>
#include <holoscan/core/resources/gxf/transmitter.hpp>

namespace holoscan {

class SubscriberAvailableCondition : public Condition {
 public:
  HOLOSCAN_CONDITION_FORWARD_ARGS(SubscriberAvailableCondition)
  SubscriberAvailableCondition() = default;

  void setup(ComponentSpec& spec) override;
  void initialize() override;

  void update_state(int64_t timestamp) override;
  void check(int64_t timestamp, SchedulingStatusType* status_type,
             int64_t* target_timestamp) const override;
  void on_execute(int64_t timestamp) override;

 private:
  void resolve_pubsub_transmitter();

  Parameter<std::shared_ptr<Transmitter>> transmitter_;
  Parameter<uint64_t> min_subscriber_count_;
  Parameter<bool> require_pubsub_connector_;
  Parameter<int64_t> poll_period_ms_;
  Parameter<int64_t> stabilization_ms_;
  Parameter<bool> latch_ready_;
  Parameter<bool> ready_on_shutdown_;

  std::shared_ptr<PubSubTransmitter> pubsub_transmitter_;
  std::atomic<SchedulingStatusType> current_state_{SchedulingStatusType::kWaitTime};
  std::atomic<int64_t> target_timestamp_{0};
  int64_t matched_since_timestamp_ = -1;
  std::atomic<bool> latched_ready_{false};
};

}  // namespace holoscan

#endif/* HOLOSCAN_PUBSUB_RUNTIME_CONDITIONS_SUBSCRIBER_AVAILABLE_HPP */