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// Copyright (c) 2021 by Apex.AI Inc. All rights reserved.
//
// 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.
//
// SPDX-License-Identifier: Apache-2.0
#include "iceoryx_binding_c/listener.h"
#include "iceoryx_binding_c/runtime.h"
#include "iceoryx_binding_c/subscriber.h"
#include "iceoryx_binding_c/types.h"
#include "iceoryx_binding_c/user_trigger.h"
#include "sleep_for.h"
#include "topic_data.h"
#if !defined(_WIN32)
#include <pthread.h>
#endif
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
bool keepRunning = true;
iox_user_trigger_t heartbeat;
static void sigHandler(int signalValue)
{
(void)signalValue;
// caught SIGINT or SIGTERM, now exit gracefully
keepRunning = false;
}
struct cache_t
{
struct CounterTopic value;
bool isSet;
};
struct cache_t leftCache = {.isSet = false};
struct cache_t rightCache = {.isSet = false};
//! [heartbeat callback]
void heartbeatCallback(iox_user_trigger_t userTrigger)
{
(void)userTrigger;
printf("heartbeat received\n");
fflush(stdout);
}
//! [heartbeat callback]
void* cyclicHeartbeatTrigger(void* dontCare)
{
(void)dontCare;
while (keepRunning)
{
iox_user_trigger_trigger(heartbeat);
sleep_for(4000);
}
return NULL;
}
//! [subscriber callback]
void onSampleReceivedCallback(iox_sub_t subscriber)
{
//! [get data]
const struct CounterTopic* userPayload;
if (iox_sub_take_chunk(subscriber, (const void**)&userPayload) == ChunkReceiveResult_SUCCESS)
{
iox_service_description_t serviceDescription = iox_sub_get_service_description(subscriber);
if (strcmp(serviceDescription.instanceString, "FrontLeft") == 0)
{
leftCache.value = *userPayload;
leftCache.isSet = true;
}
else if (strcmp(serviceDescription.instanceString, "FrontRight") == 0)
{
rightCache.value = *userPayload;
rightCache.isSet = true;
}
printf("received: %d\n", userPayload->counter);
fflush(stdout);
}
//! [get data]
//! [process data]
if (leftCache.isSet && rightCache.isSet)
{
printf("Received samples from FrontLeft and FrontRight. Sum of %d + %d = %d\n",
leftCache.value.counter,
rightCache.value.counter,
leftCache.value.counter + rightCache.value.counter);
fflush(stdout);
leftCache.isSet = false;
rightCache.isSet = false;
}
//! [process data]
}
//! [subscriber callback]
int main()
{
signal(SIGINT, sigHandler);
signal(SIGTERM, sigHandler);
iox_runtime_init("iox-c-callback-subscriber");
// the listener starts a background thread and the callbacks of the attached events
// will be called in this background thread when they are triggered
//! [create listener]
iox_listener_storage_t listenerStorage;
iox_listener_t listener = iox_listener_init(&listenerStorage);
//! [create listener]
//! [create heartbeat]
iox_user_trigger_storage_t heartbeatStorage;
heartbeat = iox_user_trigger_init(&heartbeatStorage);
//! [create heartbeat]
//! [set subscriber options]
iox_sub_options_t options;
iox_sub_options_init(&options);
options.historyRequest = 10U;
options.queueCapacity = 50U;
options.nodeName = "iox-c-callback-subscriber-node";
//! [set subscriber options]
iox_sub_storage_t subscriberLeftStorage, subscriberRightStorage;
//! [create subscribers]
iox_sub_t subscriberLeft = iox_sub_init(&subscriberLeftStorage, "Radar", "FrontLeft", "Counter", &options);
iox_sub_t subscriberRight = iox_sub_init(&subscriberRightStorage, "Radar", "FrontRight", "Counter", &options);
//! [create subscribers]
#if !defined(_WIN32)
//! [send a heartbeat every 4 seconds]
pthread_t heartbeatTriggerThread;
if (pthread_create(&heartbeatTriggerThread, NULL, cyclicHeartbeatTrigger, NULL))
{
printf("failed to create thread\n");
return -1;
}
//! [send a heartbeat every 4 seconds]
#endif
//! [attach everything to the listener]
// from here on the callbacks are called when an event occurs
iox_listener_attach_user_trigger_event(listener, heartbeat, &heartbeatCallback);
iox_listener_attach_subscriber_event(
listener, subscriberLeft, SubscriberEvent_DATA_RECEIVED, &onSampleReceivedCallback);
iox_listener_attach_subscriber_event(
listener, subscriberRight, SubscriberEvent_DATA_RECEIVED, &onSampleReceivedCallback);
//! [attach everything to the listener]
//! [wait until someone presses CTRL+C]
while (keepRunning)
{
sleep_for(100);
}
//! [wait until someone presses CTRL+C]
// when the listener goes out of scope it will detach all events and when a
// subscriber goes out of scope it will detach itself from the listener
//! [optional detachEvent, but not required]
iox_listener_detach_user_trigger_event(listener, heartbeat);
iox_listener_detach_subscriber_event(listener, subscriberLeft, SubscriberEvent_DATA_RECEIVED);
iox_listener_detach_subscriber_event(listener, subscriberRight, SubscriberEvent_DATA_RECEIVED);
//! [optional detachEvent, but not required]
#if !defined(_WIN32)
pthread_join(heartbeatTriggerThread, NULL);
#endif
//! [cleanup]
iox_user_trigger_deinit(heartbeat);
iox_sub_deinit(subscriberLeft);
iox_sub_deinit(subscriberRight);
iox_listener_deinit(listener);
//! [cleanup]
return 0;
}
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