ESP8266 RTOS 开发笔记（2）TCP Client+Server

这一部分比较简单，直接根据乐鑫提供的示例代码修改即可。
如果调试过程中出现问题的话，可以通过make menuconfig之后选择
Component config ->LWIP->Enable lwip Debug,打开api_lib.c和socket.c的调试信息，通过调试信息进行错误查找定位

void socketInit()
{
    xTaskCreate(tcp_client_task, "tcp_client", 4096, NULL, 5, NULL);
    xTaskCreate(tcp_server_task, "tcp_server", 4096, NULL, 5, NULL);
}

在APP_main()函数添加socketInit();
测试服务器不支持IPV6，故IPV6部分代码删除

tcp_client_task

static void tcp_client_task(void *pvParameters)
{
    char rx_buffer[128];
    char addr_str[128];
    int addr_family;
    int ip_protocol;    
    while (1) {

        struct sockaddr_in destAddr;
        destAddr.sin_addr.s_addr = inet_addr(HOST_IP_ADDR);
        destAddr.sin_family = AF_INET;
        destAddr.sin_port = htons(PORT);
        addr_family = AF_INET;
        ip_protocol = IPPROTO_IP;
        inet_ntoa_r(destAddr.sin_addr, addr_str, sizeof(addr_str) - 1);


        int sock =  socket(addr_family, SOCK_STREAM, ip_protocol);
        if (sock < 0) {
            ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
            break;
        }
        ESP_LOGI(TAG, "Socket created");

        int err = connect(sock, (struct sockaddr *)&destAddr, sizeof(destAddr));
        if (err != 0) {
            ESP_LOGE(TAG, "Socket unable to connect: errno %d", errno);
            close(sock);
            continue;
        }
        ESP_LOGI(TAG, "Successfully connected");
        if (err==0){protocolSend(sock,NULL,0,0,0x02);}
        //if (err==0){send(socket,hb,20,0);}
        while (1) {
            //int err = send(sock, payload, strlen(payload), 0);
            //私有协议服务器，对传输的数据增加了一层封装
            int err = protocolSend(sock,payload,strlen(payload),0,0x01);
            if (err < 0) {
                ESP_LOGE(TAG, "Error occured during sending: errno %d", errno);
                break;
            }
            int len = recv(sock, rx_buffer, sizeof(rx_buffer) - 1, 0);
            // Error occured during receiving
            if (len < 0) {
                ESP_LOGE(TAG, "recv failed: errno %d", errno);
                break;
            }
            // Data received
            else {
                rx_buffer[len] = 0; // Null-terminate whatever we received and treat like a string
                ESP_LOGI(TAG, "Received %d bytes from %s:", len, addr_str);
                //此处增加代码对接收数据进行处理
                 
                ESP_LOGI(TAG, "%s", rx_buffer);
            }

            vTaskDelay(2000 / portTICK_PERIOD_MS);
        }

        if (sock != -1) {
            ESP_LOGE(TAG, "Shutting down socket and restarting...");
            shutdown(sock, 0);
            close(sock);
        }
    }
    vTaskDelete(NULL);
}

tcp_server_task

使用乐鑫提供的示例echo代码，仅注释IPV6相关代码并修改本机监听端口为SPORT

static void tcp_server_task(void *pvParameters)
{
    char rx_buffer[128];
    char addr_str[128];
    int addr_family;
    int ip_protocol;

    while (1) {

//#ifdef CONFIG_EXAMPLE_IPV4
        struct sockaddr_in destAddr;
        destAddr.sin_addr.s_addr = htonl(INADDR_ANY);
        destAddr.sin_family = AF_INET;
        destAddr.sin_port = htons(SPORT);
        addr_family = AF_INET;
        ip_protocol = IPPROTO_IP;
        inet_ntoa_r(destAddr.sin_addr, addr_str, sizeof(addr_str) - 1);
/*#else // IPV6
        struct sockaddr_in6 destAddr;
        bzero(&destAddr.sin6_addr.un, sizeof(destAddr.sin6_addr.un));
        destAddr.sin6_family = AF_INET6;
        destAddr.sin6_port = htons(PORT);
        addr_family = AF_INET6;
        ip_protocol = IPPROTO_IPV6;
        inet6_ntoa_r(destAddr.sin6_addr, addr_str, sizeof(addr_str) - 1);
#endif*/

        int listen_sock = socket(addr_family, SOCK_STREAM, ip_protocol);
        if (listen_sock < 0) {
            ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
            break;
        }
        ESP_LOGI(TAG, "Socket created");

        int err = bind(listen_sock, (struct sockaddr *)&destAddr, sizeof(destAddr));
        if (err != 0) {
            ESP_LOGE(TAG, "Socket unable to bind: errno %d", errno);
            break;
        }
        ESP_LOGI(TAG, "Socket binded");

        err = listen(listen_sock, 1);
        if (err != 0) {
            ESP_LOGE(TAG, "Error occured during listen: errno %d", errno);
            break;
        }
        ESP_LOGI(TAG, "Socket listening");

#ifdef CONFIG_EXAMPLE_IPV6
        struct sockaddr_in6 sourceAddr; // Large enough for both IPv4 or IPv6
#else
        struct sockaddr_in sourceAddr;
#endif
        uint addrLen = sizeof(sourceAddr);
        int sock = accept(listen_sock, (struct sockaddr *)&sourceAddr, &addrLen);
        if (sock < 0) {
            ESP_LOGE(TAG, "Unable to accept connection: errno %d", errno);
            break;
        }
        ESP_LOGI(TAG, "Socket accepted");

        while (1) {
            int len = recv(sock, rx_buffer, sizeof(rx_buffer) - 1, 0);
            // Error occured during receiving
            if (len < 0) {
                ESP_LOGE(TAG, "recv failed: errno %d", errno);
                break;
            }
            // Connection closed
            else if (len == 0) {
                ESP_LOGI(TAG, "Connection closed");
                break;
            }
            // Data received
            else {
/*#ifdef CONFIG_EXAMPLE_IPV6
                // Get the sender's ip address as string
                if (sourceAddr.sin6_family == PF_INET) {
                    inet_ntoa_r(((struct sockaddr_in *)&sourceAddr)->sin_addr.s_addr, addr_str, sizeof(addr_str) - 1);
                } else if (sourceAddr.sin6_family == PF_INET6) {
                    inet6_ntoa_r(sourceAddr.sin6_addr, addr_str, sizeof(addr_str) - 1);
                }
#else*/
                inet_ntoa_r(((struct sockaddr_in *)&sourceAddr)->sin_addr.s_addr, addr_str, sizeof(addr_str) - 1);
//#endif

                rx_buffer[len] = 0; // Null-terminate whatever we received and treat like a string
                ESP_LOGI(TAG, "Received %d bytes from %s:", len, addr_str);
                ESP_LOGI(TAG, "%s", rx_buffer);

                int err = send(sock, rx_buffer, len, 0);
                if (err < 0) {
                    ESP_LOGE(TAG, "Error occured during sending: errno %d", errno);
                    break;
                }
            }
        }

        if (sock != -1) {
            ESP_LOGE(TAG, "Shutting down socket and restarting...");
            shutdown(sock, 0);
            close(sock);
            //这里处理有问题
        }
    }
    vTaskDelete(NULL);
}

经测试发现TCP Server的示例程序有问题，断开后无法重连，报错：Socket unable to bind: errno 112
论坛查找后简单修改即可：

        if (sock != -1) {
            ESP_LOGE(TAG, "Shutting down socket and restarting...");
            shutdown(sock, 0);
            close(sock);
            //这里处理有问题,增加三行代码
            shutdown(listen_sock,0);
            close(listen_sock);
            vTaskDelay(5);
        }