neuron/plugins/sample/plugin_sample_app.c

/**
 * NEURON IIoT System for Industry 4.0
 * Copyright (C) 2020-2021 EMQ Technologies Co., Ltd All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 **/

#include <assert.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "neuron.h"

#define SAMPLE_APP_PLUGIN_DESCR \
    "A sample plugin for demonstrate how to write a neuron application plugin"

const neu_plugin_module_t neu_plugin_module;

struct neu_plugin {
    neu_plugin_common_t common;
    pthread_t           work_tid;
    uint32_t            new_event_id;
};

static uint32_t plugin_get_event_id(neu_plugin_t *plugin)
{
    uint32_t req_id;

    plugin->new_event_id++;
    if (plugin->new_event_id == 0) {
        plugin->new_event_id = 1;
    }

    req_id = plugin->new_event_id;
    return req_id;
}

static void *sample_app_work_loop(void *arg)
{
    neu_plugin_t *plugin;

    plugin = (neu_plugin_t *) arg;
    usleep(10000);

    const adapter_callbacks_t *adapter_callbacks;
    adapter_callbacks = plugin->common.adapter_callbacks;

    neu_event_notify_t event;
    neu_event_read_t   evt_read;

    evt_read.grp_config = NULL;
    evt_read.addr       = 3;
    event.type          = NEU_EVENT_READ;
    event.event_id      = plugin_get_event_id(plugin);
    event.buf           = (void *) &evt_read;
    event.buf_len       = sizeof(neu_event_read_t);
    log_info("Send a read event");
    adapter_callbacks->event_notify(plugin->common.adapter, &event);
    return NULL;
}

static neu_plugin_t *
sample_app_plugin_open(neu_adapter_t *            adapter,
                       const adapter_callbacks_t *callbacks)
{
    neu_plugin_t *plugin;

    if (adapter == NULL || callbacks == NULL) {
        log_error("Open plugin with NULL adapter or callbacks");
        return NULL;
    }

    plugin = (neu_plugin_t *) malloc(sizeof(neu_plugin_t));
    if (plugin == NULL) {
        log_error("Failed to allocate plugin %s",
                  neu_plugin_module.module_name);
        return NULL;
    }

    plugin->common.adapter           = adapter;
    plugin->common.adapter_callbacks = callbacks;
    plugin->new_event_id             = 1;

    int rv;
    rv = pthread_create(&plugin->work_tid, NULL, sample_app_work_loop, plugin);
    if (rv != 0) {
        log_error("Failed to create work thread for sample app plugin");
        free(plugin);
        return NULL;
    }
    log_info("Success to create plugin: %s", neu_plugin_module.module_name);
    return plugin;
}

static int sample_app_plugin_close(neu_plugin_t *plugin)
{
    int rv = 0;

    pthread_join(plugin->work_tid, NULL);
    free(plugin);
    log_info("Success to free plugin: %s", neu_plugin_module.module_name);
    return rv;
}

static int sample_app_plugin_init(neu_plugin_t *plugin)
{
    int rv = 0;

    (void) plugin;

    log_info("Initialize plugin: %s", neu_plugin_module.module_name);
    return rv;
}

static int sample_app_plugin_uninit(neu_plugin_t *plugin)
{
    int rv = 0;

    (void) plugin;

    log_info("Uninitialize plugin: %s", neu_plugin_module.module_name);
    return rv;
}

static int sample_app_plugin_config(neu_plugin_t *plugin, neu_config_t *configs)
{
    int rv = 0;

    (void) plugin;
    (void) configs;

    log_info("config plugin: %s", neu_plugin_module.module_name);
    return rv;
}

static int sample_app_plugin_request(neu_plugin_t *plugin, neu_request_t *req)
{
    int rv = 0;

    if (plugin == NULL || req == NULL) {
        log_warn("The plugin pointer or request is NULL");
        return (-1);
    }

    log_info("send request to plugin: %s", neu_plugin_module.module_name);
    const adapter_callbacks_t *adapter_callbacks;
    adapter_callbacks = plugin->common.adapter_callbacks;

    switch (req->req_type) {
    case NEU_REQRESP_TRANS_DATA: {
        neu_reqresp_data_t *neu_data;
        const char *        req_str;

        assert(req->buf_len == sizeof(neu_reqresp_data_t));
        neu_data = (neu_reqresp_data_t *) req->buf;
        req_str  = neu_variable_get_str(neu_data->data_var);
        log_debug("recevied str: %s", req_str);
        break;
    }

    default:
        break;
    }
    return rv;
}

static int sample_app_plugin_event_reply(neu_plugin_t *     plugin,
                                         neu_event_reply_t *reply)
{
    int rv = 0;

    (void) plugin;
    (void) reply;

    log_info("reply event to plugin: %s", neu_plugin_module.module_name);
    return rv;
}

static const neu_plugin_intf_funs_t plugin_intf_funs = {
    .open        = sample_app_plugin_open,
    .close       = sample_app_plugin_close,
    .init        = sample_app_plugin_init,
    .uninit      = sample_app_plugin_uninit,
    .config      = sample_app_plugin_config,
    .request     = sample_app_plugin_request,
    .event_reply = sample_app_plugin_event_reply
};

const neu_plugin_module_t neu_plugin_module = {
    .version      = NEURON_PLUGIN_VER_1_0,
    .module_name  = "neuron-sample-app-plugin",
    .module_descr = SAMPLE_APP_PLUGIN_DESCR,
    .intf_funs    = &plugin_intf_funs
};