本篇使用的是lwip编写tcp客户端。需要提前准备好一个PARAM_HOTSPOT_SSID宏定义的热点，并且密码为PARAM_HOTSPOT_PSK。还需要准备一个tcp服务，服务ip为PARAM_SERVER_ADDR宏定义，端口为PARAM_SERVER_PORT宏定义。
修改网络参数
在Hi3861开发板上运行上述四个测试程序之前，需要根据你的无线路由、Linux系统IP修改 net_params.h文件的相关代码：
- PARAM_HOTSPOT_SSID 修改为你的热点名称
- PARAM_HOTSPOT_PSK 修改为你的热点密码；
- PARAM_SERVER_ADDR 修改为你的服务器IP地址；
- PARAM_SERVER_PORT 修改为你的服务器端口号；
LwIP Socket API编程tcp客户端主要步骤
创建Socket socket()
设置服务器地址和端口 sockaddr_in
连接到服务器 connect()
发送和接收数据 send() write() recv() read()
关闭Socket close()
代码编写
修改D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\BUILD.gn文件
# Copyright (c) 2023 Beijing HuaQing YuanJian Education Technology Co., Ltd
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License. import("//build/lite/config/component/lite_component.gni")lite_component("demo") {features = [#"base_00_helloworld:base_helloworld_example",#"base_01_led:base_led_example",#"base_02_loopkey:base_loopkey_example",#"base_03_irqkey:base_irqkey_example",#"base_04_adc:base_adc_example",#"base_05_pwm:base_pwm_example",#"base_06_ssd1306:base_ssd1306_example",#"kernel_01_task:kernel_task_example",#"kernel_02_timer:kernel_timer_example",#"kernel_03_event:kernel_event_example",#"kernel_04_mutex:kernel_mutex_example",#"kernel_05_semaphore_as_mutex:kernel_semaphore_as_mutex_example",#"kernel_06_semaphore_for_sync:kernel_semaphore_for_sync_example",#"kernel_07_semaphore_for_count:kernel_semaphore_for_count_example",#"kernel_08_message_queue:kernel_message_queue_example",#"wifi_09_hotspot:wifi_hotspot_example",#"wifi_10_sta:wifi_sta_example",#"tcp_11_server:tcp_server_example","tcp_12_client:tcp_client_example",]
}创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client文件夹
文件夹中创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client\BUILD.gn文件
#Copyright (C) 2021 HiHope Open Source Organization .
#Licensed under the Apache License, Version 2.0 (the "License");
#you may not use this file except in compliance with the License.
#You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
#Unless required by applicable law or agreed to in writing, software
#distributed under the License is distributed on an "AS IS" BASIS,
#WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#See the License for the specific language governing permissions and
#
#limitations under the License.static_library("tcp_client_example") {# uncomment one of following line, to enable one test:sources = ["tcp_client_example.c"]sources += ["wifi_connecter.c"]include_dirs = ["//utils/native/lite/include","//kernel/liteos_m/kal","//foundation/communication/wifi_lite/interfaces/wifiservice",]
}添加了wifi_connecter.c文件的编译，这个文件中有链接wifi的函数。
文件夹中创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client\net_common.h文件，文件主要引入一些头文件。
/** Copyright (C) 2021 HiHope Open Source Organization .* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and** limitations under the License.*/#ifndef NET_COMMON_H
#define NET_COMMON_H// __arm__ and __aarch64__ for HarmonyOS with liteos-a kernel
// __i386__ and __x86_64__ for Unix like OS
#if defined(__arm__) || defined(__aarch64__) || defined(__i386__) || defined(__x86_64__)
#define HAVE_BSD_SOCKET 1
#else
#define HAVE_BSD_SOCKET 0
#endif#if defined(__riscv) // for wifiiot(HarmonyOS on Hi3861 with liteos-m kernel)
#define HAVE_LWIP_SOCKET 1
#else
#define HAVE_LWIP_SOCKET 0
#endif#if HAVE_BSD_SOCKET
#include <sys/types.h> // for AF_INET SOCK_STREAM
#include <sys/socket.h> // for socket
#include <netinet/in.h> // for sockaddr_in
#include <arpa/inet.h> // for inet_pton
#elif HAVE_LWIP_SOCKET
#include "lwip/sockets.h"
#ifndef close
#define close(fd) lwip_close(fd)
#endif
#else
#error "Unknow platform!"
#endif#endif // NET_COMMON_H文件夹中创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client\wifi_connecter.h文件，该头文件包含wifi连接的宏。
/** Copyright (C) 2021 HiHope Open Source Organization .* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and** limitations under the License.*/#ifndef WIFI_CONNECTER_H
#define WIFI_CONNECTER_H#include "wifi_device.h"#ifndef PARAM_HOTSPOT_SSID
#define PARAM_HOTSPOT_SSID "HarmonyOS" // your AP SSID
#endif#ifndef PARAM_HOTSPOT_PSK
#define PARAM_HOTSPOT_PSK "1234567890" // your AP PSK
#endif#ifndef PARAM_HOTSPOT_TYPE
#define PARAM_HOTSPOT_TYPE WIFI_SEC_TYPE_PSK // defined in wifi_device_config.h
#endif#ifndef PARAM_SERVER_ADDR
#define PARAM_SERVER_ADDR "192.168.137.1" // your PC IP address
#endif#ifndef PARAM_SERVER_PORT
#define PARAM_SERVER_PORT 5678
#endifint ConnectToHotspot(WifiDeviceConfig* apConfig);void DisconnectWithHotspot(int netId);#endif // WIFI_CONNECTER_H文件夹中创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client\wifi_connecter.c文件，wifi连接的实现。
/** Copyright (C) 2021 HiHope Open Source Organization .* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and** limitations under the License.*/#include "wifi_device.h"
#include "cmsis_os2.h"#include "lwip/netifapi.h"
#include "lwip/api_shell.h"#define IDX_0 0
#define IDX_1 1
#define IDX_2 2
#define IDX_3 3
#define IDX_4 4
#define IDX_5 5
#define DELAY_TICKS_10 (10)
#define DELAY_TICKS_100 (100)static void PrintLinkedInfo(WifiLinkedInfo* info)
{if (!info) return;static char macAddress[32] = {0};unsigned char* mac = info->bssid;snprintf(macAddress, sizeof(macAddress), "%02X:%02X:%02X:%02X:%02X:%02X",mac[IDX_0], mac[IDX_1], mac[IDX_2], mac[IDX_3], mac[IDX_4], mac[IDX_5]);printf("bssid: %s, rssi: %d, connState: %d, reason: %d, ssid: %s\r\n",macAddress, info->rssi, info->connState, info->disconnectedReason, info->ssid);
}static volatile int g_connected = 0;static void OnWifiConnectionChanged(int state, WifiLinkedInfo* info)
{if (!info) return;printf("%s %d, state = %d, info = \r\n", __FUNCTION__, __LINE__, state);PrintLinkedInfo(info);if (state == WIFI_STATE_AVALIABLE) {g_connected = 1;} else {g_connected = 0;}
}static void OnWifiScanStateChanged(int state, int size)
{printf("%s %d, state = %X, size = %d\r\n", __FUNCTION__, __LINE__, state, size);
}static WifiEvent g_defaultWifiEventListener = {.OnWifiConnectionChanged = OnWifiConnectionChanged,.OnWifiScanStateChanged = OnWifiScanStateChanged
};static struct netif* g_iface = NULL;err_t netifapi_set_hostname(struct netif *netif, char *hostname, u8_t namelen);int ConnectToHotspot(WifiDeviceConfig* apConfig)
{WifiErrorCode errCode;int netId = -1;errCode = RegisterWifiEvent(&g_defaultWifiEventListener);printf("RegisterWifiEvent: %d\r\n", errCode);errCode = EnableWifi();printf("EnableWifi: %d\r\n", errCode);errCode = AddDeviceConfig(apConfig, &netId);printf("AddDeviceConfig: %d\r\n", errCode);g_connected = 0;errCode = ConnectTo(netId);printf("ConnectTo(%d): %d\r\n", netId, errCode);while (!g_connected) { // wait until connect to APosDelay(DELAY_TICKS_10);}printf("g_connected: %d\r\n", g_connected);g_iface = netifapi_netif_find("wlan0");if (g_iface) {err_t ret = 0;char* hostname = "rtplay";ret = netifapi_set_hostname(g_iface, hostname, strlen(hostname));printf("netifapi_set_hostname: %d\r\n", ret);ret = netifapi_dhcp_start(g_iface);printf("netifapi_dhcp_start: %d\r\n", ret);osDelay(DELAY_TICKS_100); // wait DHCP server give me IP
#if 1ret = netifapi_netif_common(g_iface, dhcp_clients_info_show, NULL);printf("netifapi_netif_common: %d\r\n", ret);
#else// 下面这种方式也可以打印 IP、网关、子网掩码信息ip4_addr_t ip = {0};ip4_addr_t netmask = {0};ip4_addr_t gw = {0};ret = netifapi_netif_get_addr(g_iface, &ip, &netmask, &gw);if (ret == ERR_OK) {printf("ip = %s\r\n", ip4addr_ntoa(&ip));printf("netmask = %s\r\n", ip4addr_ntoa(&netmask));printf("gw = %s\r\n", ip4addr_ntoa(&gw));}printf("netifapi_netif_get_addr: %d\r\n", ret);
#endif}return netId;
}void DisconnectWithHotspot(int netId)
{if (g_iface) {err_t ret = netifapi_dhcp_stop(g_iface);printf("netifapi_dhcp_stop: %d\r\n", ret);}WifiErrorCode errCode = Disconnect(); // disconnect with your APprintf("Disconnect: %d\r\n", errCode);errCode = UnRegisterWifiEvent(&g_defaultWifiEventListener);printf("UnRegisterWifiEvent: %d\r\n", errCode);RemoveDevice(netId); // remove AP configprintf("RemoveDevice: %d\r\n", errCode);errCode = DisableWifi();printf("DisableWifi: %d\r\n", errCode);
}文件夹中创建D:\DevEcoProjects\test\src\vendor\rtplay\rt_hi3861\demo\tcp_12_client\tcp_client_example.c文件
/** Copyright (C) 2021 HiHope Open Source Organization .* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and** limitations under the License.*/#include <stdio.h>
// #include <string.h>
#include <unistd.h>
#include "ohos_init.h"
#include "cmsis_os2.h"#include "net_common.h"
#include "wifi_connecter.h"static char request[] = "Hello";
static char response[128] = "";#define DELAY_TICKS_10 (10)void TcpClientTest(void)
{WifiDeviceConfig config = {0};// 准备AP的配置参数// strcpy(config.ssid, PARAM_HOTSPOT_SSID);// strcpy(config.preSharedKey, PARAM_HOTSPOT_PSK);strcpy_s(config.ssid, WIFI_MAX_SSID_LEN, PARAM_HOTSPOT_SSID);strcpy_s(config.preSharedKey, WIFI_MAX_KEY_LEN, PARAM_HOTSPOT_PSK);config.securityType = PARAM_HOTSPOT_TYPE;osDelay(DELAY_TICKS_10);int netId = ConnectToHotspot(&config);ssize_t retval = 0;int sockfd = socket(AF_INET, SOCK_STREAM, 0); // TCP socketstruct sockaddr_in serverAddr = {0};serverAddr.sin_family = AF_INET; // AF_INET表示IPv4协议serverAddr.sin_port = htons(PARAM_SERVER_PORT); // 端口号，从主机字节序转为网络字节序// 将主机IP地址从“点分十进制”字符串 转化为 标准格式（32位整数）if (inet_pton(AF_INET, PARAM_SERVER_ADDR, &serverAddr.sin_addr) <= 0) {printf("inet_pton failed!\r\n");goto do_cleanup;}// 尝试和目标主机建立连接，连接成功会返回0 ，失败返回 -1if (connect(sockfd, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) < 0) {printf("connect failed!\r\n");goto do_cleanup;}printf("connect to server %s success!\r\n", PARAM_SERVER_ADDR);// 建立连接成功之后，这个TCP socket描述符 —— sockfd 就具有了 “连接状态”，// 发送、接收 对端都是 connect 参数指定的目标主机和端口retval = send(sockfd, request, sizeof(request), 0);if (retval < 0) {printf("send request failed!\r\n");goto do_cleanup;}printf("send request{%s} %ld to server done!\r\n", request, retval);retval = recv(sockfd, &response, sizeof(response), 0);if (retval <= 0) {printf("send response from server failed or done, %ld!\r\n", retval);goto do_cleanup;}response[retval] = '\0';printf("recv response{%s} %ld from server done!\r\n", response, retval);do_cleanup:printf("do_cleanup...\r\n");close(sockfd);DisconnectWithHotspot(netId);
}SYS_RUN(TcpClientTest);使用build，编译成功后，使用upload进行烧录。
