OVMS3-idf/examples/system/cpp_pthread/main/cpp_pthread.cpp

/* pthread/std::thread example

   This example code is in the Public Domain (or CC0 licensed, at your option.)

   Unless required by applicable law or agreed to in writing, this
   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
   CONDITIONS OF ANY KIND, either express or implied.
*/

#include <iostream>
#include <thread>
#include <chrono>
#include <memory>
#include <string>
#include <sstream>
#include <esp_pthread.h>
#include <freertos/FreeRTOS.h>
#include <freertos/task.h>
#include <esp_log.h>

using namespace std::chrono;

const auto sleep_time = seconds
{
    5
};

void print_thread_info(const char *extra = nullptr)
{
    std::stringstream ss;
    if (extra) {
        ss << extra;
    }
    ss << "Core id: " << xPortGetCoreID()
       << ", prio: " << uxTaskPriorityGet(nullptr)
       << ", minimum free stack: " << uxTaskGetStackHighWaterMark(nullptr) << " bytes.";
    ESP_LOGI(pcTaskGetTaskName(nullptr), "%s", ss.str().c_str());
}

void thread_func_inherited()
{
    while (true) {
        print_thread_info("This is the INHERITING thread with the same parameters as our parent, including name. ");
        std::this_thread::sleep_for(sleep_time);
    }
}

void spawn_another_thread()
{
    // Create a new thread, it will inherit our configuration
    std::thread inherits(thread_func_inherited);

    while (true) {
        print_thread_info();
        std::this_thread::sleep_for(sleep_time);
    }
}

void thread_func_any_core()
{
    while (true) {
        print_thread_info("This thread (with the default name) may run on any core.");
        std::this_thread::sleep_for(sleep_time);
    }
}

void thread_func()
{
    while (true) {
        print_thread_info();
        std::this_thread::sleep_for(sleep_time);
    }
}

esp_pthread_cfg_t create_config(const char *name, int core_id, int stack, int prio)
{
    auto cfg = esp_pthread_get_default_config();
    cfg.thread_name = name;
    cfg.pin_to_core = core_id;
    cfg.stack_size = stack;
    cfg.prio = prio;
    return cfg;
}

extern "C" void app_main(void)
{
    // Create a thread using deafult values that can run on any core
    auto cfg = esp_pthread_get_default_config();
    esp_pthread_set_cfg(&cfg);
    std::thread any_core(thread_func_any_core);

    // Create a thread on core 0 that spawns another thread, they will both have the same name etc.
    cfg = create_config("Thread 1", 0, 3 * 1024, 5);
    cfg.inherit_cfg = true;
    esp_pthread_set_cfg(&cfg);
    std::thread thread_1(spawn_another_thread);

    // Create a thread on core 1.
    cfg = create_config("Thread 2", 1, 3 * 1024, 5);
    esp_pthread_set_cfg(&cfg);
    std::thread thread_2(thread_func);

    // Let the main task do something too
    while (true) {
        std::stringstream ss;
        ss << "core id: " << xPortGetCoreID()
           << ", prio: " << uxTaskPriorityGet(nullptr)
           << ", minimum free stack: " << uxTaskGetStackHighWaterMark(nullptr) << " bytes.";
        ESP_LOGI(pcTaskGetTaskName(nullptr), "%s", ss.str().c_str());
        std::this_thread::sleep_for(sleep_time);
    }
}