基于C语言Socket编程的智能家居控制系统

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sqlite3.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <pthread.h>
#include <json-c/json.h>

#define MAX_CLIENTS 10
#define DATABASE 'smart_home.db'

typedef struct {
    int client_socket;
    sqlite3 *db;
} client_data;

void *handle_client(void *arg) {
    client_data *data = (client_data *)arg;
    int client_socket = data->client_socket;
    sqlite3 *db = data->db;
    char buffer[1024];
    memset(buffer, 0, sizeof(buffer));

    // 读取客户端请求
    ssize_t bytes_read = read(client_socket, buffer, sizeof(buffer));
    if (bytes_read <= 0) {
        perror('读取客户端请求出错');
        close(client_socket);
        free(data);
        return NULL;
    }

    // 解析JSON请求
    struct json_object *json_request = json_tokener_parse(buffer);
    if (json_request == NULL) {
        fprintf(stderr, '解析JSON请求出错：%s\n', buffer);
        close(client_socket);
        free(data);
        return NULL;
    }

    // 从JSON请求中获取用户ID
    struct json_object *json_userid;
    json_object_object_get_ex(json_request, 'userid', &json_userid);
    int userid = json_object_get_int(json_userid);

    // 查询设备状态的数据库
    char query[256];
    sprintf(query, 'SELECT device_name, value FROM Status WHERE uid = %d', userid);
    sqlite3_stmt *stmt;
    if (sqlite3_prepare_v2(db, query, -1, &stmt, NULL) != SQLITE_OK) {
        fprintf(stderr, '准备数据库查询出错：%s\n', sqlite3_errmsg(db));
        close(client_socket);
        free(data);
        return NULL;
    }

    // 处理查询结果
    char response[1024];
    memset(response, 0, sizeof(response));
    while (sqlite3_step(stmt) == SQLITE_ROW) {
        const char *device_name = (const char *)sqlite3_column_text(stmt, 0);
        const char *value = (const char *)sqlite3_column_text(stmt, 1);

        // 分析设备状态并生成建议
        if (strcmp(device_name, 'air_conditioner') == 0) {
            int temperature = atoi(value);
            if (temperature < 24) {
                strcat(response, '空调温度太低，请将其调高到26°C。\n');
            }
        } else if (strcmp(device_name, 'humidifier') == 0) {
            int humidity = atoi(value);
            if (humidity < 40 || humidity > 70) {
                strcat(response, '加湿器湿度太高或太低，请调整湿度。\n');
            }
        }
    }

    // 发送响应给客户端
    if (strlen(response) > 0) {
        write(client_socket, response, strlen(response));
    } else {
        write(client_socket, '无建议。', 14);
    }

    // 清理
    sqlite3_finalize(stmt);
    json_object_put(json_request);
    close(client_socket);
    free(data);
    return NULL;
}

int main() {
    // 初始化SQLite数据库
    sqlite3 *db;
    if (sqlite3_open(DATABASE, &db) != SQLITE_OK) {
        fprintf(stderr, '打开数据库出错：%s\n', sqlite3_errmsg(db));
        return 1;
    }

    // 创建套接字
    int server_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (server_socket == -1) {
        perror('创建套接字出错');
        return 1;
    }

    // 将套接字绑定到IP和端口
    struct sockaddr_in server_address;
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(8080);
    server_address.sin_addr.s_addr = INADDR_ANY;
    if (bind(server_socket, (struct sockaddr *)&server_address, sizeof(server_address)) == -1) {
        perror('绑定套接字出错');
        return 1;
    }

    // 监听传入的连接
    if (listen(server_socket, MAX_CLIENTS) == -1) {
        perror('监听连接出错');
        return 1;
    }

    printf('服务器正在监听端口8080...\n');

    while (1) {
        // 接受传入的连接
        struct sockaddr_in client_address;
        socklen_t client_address_length = sizeof(client_address);
        int client_socket = accept(server_socket, (struct sockaddr *)&client_address, &client_address_length);
        if (client_socket == -1) {
            perror('接受连接出错');
            continue;
        }

        // 创建线程处理客户端
        client_data *data = malloc(sizeof(client_data));
        data->client_socket = client_socket;
        data->db = db;
        pthread_t thread;
        if (pthread_create(&thread, NULL, handle_client, data) != 0) {
            perror('创建线程出错');
            close(client_socket);
            free(data);
        }
    }

    // 关闭SQLite数据库
    sqlite3_close(db);

    // 关闭服务器套接字
    close(server_socket);

    return 0;
}