智能家居系统：空调和加湿器状态建议生成

本文将介绍如何使用C语言开发一个简单的智能家居系统，根据空调和加湿器的状态，生成相应的建议信息并发送给客户端。

系统架构：

**服务器端：**负责监听客户端连接、接收客户端请求、获取设备状态、生成建议信息并发送给客户端。
**数据库：**用于存储设备状态信息。
**客户端：**发送请求给服务器，接收服务器返回的建议信息。

代码示例：

#include <stdio.h>
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include 'handle.h'

int receiveUserId(int sockfd) {
    int userid;
    ssize_t recvSize = recv(sockfd, &userid, sizeof(int), 0);
    if (recvSize == -1 || recvSize == 0 || recvSize != sizeof(int)) {
        perror("接收userid失败");
        return -1;
    }
    return ntohl(userid);
}

sqlite3_stmt* prepareStatement(sqlite3 *db, int userid) {
    char sql[100];
    snprintf(sql, sizeof(sql), "SELECT * FROM Status WHERE uid = %d", userid);
    sqlite3_stmt *stmt = NULL;
    int rc = sqlite3_prepare_v2(db, sql, -1, &stmt, NULL);
    if (rc != SQLITE_OK) {
        fprintf(stderr, "无法执行的语句: %s\n", sqlite3_errmsg(db));
        return NULL;
    }
    return stmt;
}

void initializeStatus(Status *status) {
    memset(status, 0, sizeof(Status));
    status->uid = 0;
    status->device_name[0] = '\0';
}

void updateAcStatus(Status *acStatus, int uid, const unsigned char *device_state, const unsigned char *value) {
    acStatus->uid = uid;
    strncpy(acStatus->device_state, device_state, sizeof(acStatus->device_state) - 1);
    acStatus->device_state[sizeof(acStatus->device_state) - 1] = '\0';
    strncpy(acStatus->value, value, sizeof(acStatus->value) - 1);
    acStatus->value[sizeof(acStatus->value) - 1] = '\0';

}

void generateAcSuggestion(const Status *acStatus, char *suggestion) {
    int temperature = atoi(acStatus->value);
    
    if (temperature < 24) {
        snprintf(suggestion, MAX_BUFFER_SIZE, "空调温度过低，建议提高温度至26℃");
    } else if(temperature>35){
        snprintf(suggestion, MAX_BUFFER_SIZE, "空调温度过高，建议降低温度至26℃");
    }
    else{
        snprintf(suggestion, MAX_BUFFER_SIZE, "空调温度适宜");
    }
}

void generateHumidifierSuggestion(const Status *humidifierStatus, char *suggestion) {
    int humidity = atoi(humidifierStatus->value);
    if (humidity < 40) {
        snprintf(suggestion, MAX_BUFFER_SIZE, "加湿器湿度过低，建议调整加湿器湿度");
    } else if (humidity > 70) {
        snprintf(suggestion, MAX_BUFFER_SIZE, "加湿器湿度过高，建议调整加湿器湿度");
    } else {
        snprintf(suggestion, MAX_BUFFER_SIZE, "加湿器湿度适宜");
    }
}

char* combineSuggestions(const char *suggestion, const char *humidifierSuggestion) {
    int combinedSuggestionSize = strlen(suggestion) + strlen(humidifierSuggestion) + 2;
    char *combinedSuggestion = malloc(combinedSuggestionSize);
    snprintf(combinedSuggestion, combinedSuggestionSize, "%s\n%s", suggestion, humidifierSuggestion);
    return combinedSuggestion;
}

void sendSuggestion(int sockfd, char *suggestion) {
    ssize_t sendSize = send(sockfd, suggestion, strlen(suggestion)+1, 0);
    if (sendSize == -1) {
        perror("发送失败\nsend");
        free(suggestion);
        return;
    } else {
        printf("建议已发送\n");
    }
}

void handleClientRequest(ServerContext *context) {
    int userid = receiveUserId(context->sockfd);
    if (userid == -1) {
        perror("接收userid失败");
        return;
    }

    printf("客户端已连接\n");
    printf("userid:%d\n", userid);

    sqlite3_stmt *stmt = prepareStatement(context->db, userid);
    if (stmt == NULL) {
        fprintf(stderr, "无法执行的语句: %s\n", sqlite3_errmsg(context->db));
        return;
    }

    Status acStatus, humidifierStatus;
    initializeStatus(&acStatus);
    initializeStatus(&humidifierStatus);

    char suggestion[MAX_BUFFER_SIZE] = "";
    char humidifierSuggestion[MAX_BUFFER_SIZE] = "";

    int acOpened = 0;
    int humidifierOpened = 0;

    while (sqlite3_step(stmt) == SQLITE_ROW) {
        int uid = sqlite3_column_int(stmt, 1);
        const unsigned char *device_name = sqlite3_column_text(stmt, 2);
        const unsigned char *device_state = sqlite3_column_text(stmt, 3);
        const unsigned char *value = sqlite3_column_text(stmt, 4);
     
        if (device_name != NULL && device_state != NULL && value != NULL ) {

            if (strcmp(device_name, "空调") == 0) {
                if (strcmp(device_state, "开启") == 0){
                    updateAcStatus(&acStatus, uid, device_state, value);
                    generateAcSuggestion(&acStatus, suggestion);
                    acOpened = 1;
                }

            } else if (strcmp(device_name, "加湿器") == 0) {
                if (strcmp(device_state, "开启") == 0){
                    updateAcStatus(&humidifierStatus, uid, device_state, value);
                    generateHumidifierSuggestion(&humidifierStatus, humidifierSuggestion);
                    humidifierOpened = 1;
                }
            }
        }
    }

    sqlite3_finalize(stmt);

    if (!acOpened) {
            snprintf(suggestion, MAX_BUFFER_SIZE, "空调未开启");
        }

        if (!humidifierOpened) {
            snprintf(humidifierSuggestion, MAX_BUFFER_SIZE, "加湿器未开启");
        }

    char *combinedSuggestion = combineSuggestions(suggestion, humidifierSuggestion);
    sendSuggestion(context->sockfd, combinedSuggestion);
    printf("建议为：\n%s\n", combinedSuggestion);

    free(combinedSuggestion);

    // 关闭连接
    shutdown(context->sockfd, SHUT_RDWR);
    printf("按下Ctrl + Z登出...\n");
}

void handleClientRequests(ServerContext *context, int sockfd) {
    fd_set readfds;
    int maxfd = sockfd;

    while (1) {
        FD_ZERO(&readfds);
        FD_SET(sockfd, &readfds);

        int activity = select(maxfd + 1, &readfds, NULL, NULL, NULL);
        if (activity == -1) {
            perror("select");
            break;
        }

        if (FD_ISSET(sockfd, &readfds)) {
            int clientSockfd = accept(sockfd, (struct sockaddr *)&context->client_addr, &context->client_addr_len);
            if (clientSockfd == -1) {
                perror("套接字接收失败\naccept");
                break;
            }

            context->sockfd = clientSockfd;
            handleClientRequest(context);

            close(clientSockfd);
        }
    }
}

代码逻辑：

**接收用户ID：**服务器接收客户端发送的用户ID。
**获取设备状态：**服务器根据用户ID从数据库中查询设备状态信息，并存储在acStatus和humidifierStatus结构体中。
**生成建议信息：**根据设备状态信息，调用generateAcSuggestion和generateHumidifierSuggestion函数生成空调和加湿器的建议信息。
**合并建议信息：**调用combineSuggestions函数将空调和加湿器的建议信息合并成一个字符串。
**发送建议信息：**将合并后的建议信息发送给客户端。

运行结果：

root@WIN-K3C9KG85CB8:/home/SmartHome/Server# ./main.exec
正在连接中...
客户端已连接
userid:1
建议已发送
建议为：
空调温度过低，建议提高温度至26℃
加湿器湿度过低，建议调整加湿器湿度
按下Ctrl + Z登出...

注意：

代码示例中使用了sqlite3库进行数据库操作，需要在编译时链接sqlite3库。
代码示例中假设数据库表名为Status，字段包括uid、device_name、device_state和value。
代码示例中使用了MAX_BUFFER_SIZE宏定义，需要根据实际情况调整。

总结：

本文介绍了一个简单的智能家居系统，能够根据空调和加湿器的状态，生成相应的建议信息并发送给客户端。该系统可以作为智能家居系统开发的参考，并可以根据实际需求进行扩展。