neuron/plugins/plugin_sample.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 <stdio.h>
#include <stdlib.h>

#include "neuron.h"

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

const neu_plugin_module_t neu_plugin_module;

struct neu_plugin {
    neu_plugin_common_t common;
};

static neu_plugin_t *sample_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;
    log_info("Success to create plugin: %s", neu_plugin_module.module_name);
    return plugin;
}

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

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

static int sample_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_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_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_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_READ: {
        neu_response_t     resp;
        static const char *resp_str = "Sample plugin read response";

        char *resp_buf;
        resp_buf = strdup(resp_str);

        memset(&resp, 0, sizeof(resp));
        resp.req_id    = req->req_id;
        resp.resp_type = NEU_REQRESP_MOVE_BUF;
        resp.buf_len   = sizeof(strlen(resp_buf) + 1);
        resp.buf       = resp_buf;
        rv = adapter_callbacks->response(plugin->common.adapter, &resp);
        break;
    }

    default:
        break;
    }
    return rv;
}

static int sample_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_plugin_open,
    .close       = sample_plugin_close,
    .init        = sample_plugin_init,
    .uninit      = sample_plugin_uninit,
    .config      = sample_plugin_config,
    .request     = sample_plugin_request,
    .event_reply = sample_plugin_event_reply
};

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