HI3861学习笔记（20）——TCP客户端
Posted Leung_ManWah
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了HI3861学习笔记（20）——TCP客户端相关的知识，希望对你有一定的参考价值。
一、TCP与UDP优缺点
1、TCP面向连接（如打电话要先拨号建立连接）;UDP是无连接的，即发送数据之前不需要建立连接。
2、TCP提供可靠的服务。也就是说，通过TCP连接传送的数据，无差错，不丢失，不重复，且按序到达;UDP尽最大努力交付，即不保证可靠交付。
TCP通过校验和，重传控制，序号标识，滑动窗口、确认应答实现可靠传输。如丢包时的重发控制，还可以对次序乱掉的分包进行顺序控制。3、UDP具有较好的实时性，工作效率比TCP高，适用于对高速传输和实时性有较高的通信或广播通信。
4、每一条TCP连接只能是点到点的;UDP支持一对一，一对多，多对一和多对多的交互通信。
5、TCP对系统资源要求较多，UDP对系统资源要求较少。
二、API说明
以下 TCP 接口位于 vendor\\hisi\\hi3861\\hi3861\\third_party\\lwip_sack\\include\\sockets.h。
业务BUILD.gn中包含路径
include_dirs = [
"//utils/native/lite/include",
"//kernel/liteos_m/components/cmsis/2.0",
"//base/iot_hardware/interfaces/kits/wifiiot_lite",
"//foundation/communication/interfaces/kits/wifi_lite/wifiservice",
"//vendor/hisi/hi3861/hi3861/third_party/lwip_sack/include/",
]
socket()bind()accept()shutdown()getpeername()getsockopt()＆setsockopt()close()read()，readv()，write()，writev()recv()send()，sendmsg()，sendto()select()fcntl()
三、TCP客户端
3.1 主要流程
3.1.1 第一步：新建socket
int sock_fd;
//创建socket
if ((sock_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
perror("create socket failed!\\r\\n");
exit(1);
3.1.2 第二步：配置将要连接的服务器信息（端口和IP）
#define TCP_SERVER_ADRESS "192.168.31.170" // 要连接TCP服务器地址
#define TCP_PORT 8888 // 要连接TCP服务器端口号
int addr_length;
//服务器的地址信息
struct sockaddr_in send_addr;
//初始化预连接的服务端地址
send_addr.sin_family = AF_INET;
send_addr.sin_port = htons(TCP_PORT);
send_addr.sin_addr.s_addr = inet_addr(TCP_SERVER_ADRESS);
addr_length = sizeof(send_addr);
3.1.3 第三步：连接服务器
connect(sock_fd, (struct sockaddr *)&send_addr, addr_length);
4.1.4 第四步：发送数据
static const char *send_data = "Hello! I'm BearPi-HM_Nano TCP Client!\\r\\n";
while (1)
······
//发送数据到服务远端
int ret;
if((ret = send(sock_fd, send_data, strlen(send_data), 0)) == -1)
perror("send:");
······
3.1.5 第五步：接收数据
char recvBuf[512];
int ret;
//接收服务端返回的字符串
if((ret = recv(sock_fd, recvBuf, sizeof(recvBuf), 0)) == -1)
printf("recv error\\r\\n");
printf("recv:%s\\r\\n", recvBuf);
3.1.6 第六步：关闭连接
//关闭这个 socket
closesocket(sock_fd);
3.2 配置SSID和密码连接WIFI创建TCP客户端
wifi_connect.c
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "lwip/netif.h"
#include "lwip/netifapi.h"
#include "lwip/ip4_addr.h"
#include "lwip/api_shell.h"
#include "cmsis_os2.h"
#include "hos_types.h"
#include "wifi_device.h"
#include "wifiiot_errno.h"
#include "ohos_init.h"
#define DEF_TIMEOUT 15
#define ONE_SECOND 1
#define SELECT_WIFI_SECURITYTYPE WIFI_SEC_TYPE_PSK
static void WiFiInit(void);
static void WaitSacnResult(void);
static int WaitConnectResult(void);
static void OnWifiScanStateChangedHandler(int state, int size);
static void OnWifiConnectionChangedHandler(int state, WifiLinkedInfo *info);
static void OnHotspotStaJoinHandler(StationInfo *info);
static void OnHotspotStateChangedHandler(int state);
static void OnHotspotStaLeaveHandler(StationInfo *info);
static int g_staScanSuccess = 0;
static int g_ConnectSuccess = 0;
static int ssid_count = 0;
WifiEvent g_wifiEventHandler = 0;
WifiErrorCode error;
#define SELECT_WLAN_PORT "wlan0"
int WifiConnect(const char *ssid, const char *psk)
WifiScanInfo *info = NULL;
unsigned int size = WIFI_SCAN_HOTSPOT_LIMIT;
static struct netif *g_lwip_netif = NULL;
osDelay(200);
printf("<--System Init-->\\r\\n");
//初始化WIFI
WiFiInit();
//使能WIFI
if (EnableWifi() != WIFI_SUCCESS)
printf("EnableWifi failed, error = %d\\r\\n", error);
return -1;
//判断WIFI是否激活
if (IsWifiActive() == 0)
printf("Wifi station is not actived.\\r\\n");
return -1;
//分配空间，保存WiFi信息
info = malloc(sizeof(WifiScanInfo) * WIFI_SCAN_HOTSPOT_LIMIT);
if (info == NULL)
return -1;
//轮询查找WiFi列表
do
//重置标志位
ssid_count = 0;
g_staScanSuccess = 0;
//开始扫描
Scan();
//等待扫描结果
WaitSacnResult();
//获取扫描列表
error = GetScanInfoList(info, &size);
while(g_staScanSuccess != 1);
//打印WiFi列表
printf("********************\\r\\n");
for(uint8_t i = 0; i < ssid_count; i++)
printf("no:%03d, ssid:%-30s, rssi:%5d\\r\\n", i+1, info[i].ssid, info[i].rssi/100);
printf("********************\\r\\n");
//连接指定的WiFi热点
for(uint8_t i = 0; i < ssid_count; i++)
if (strcmp(ssid, info[i].ssid) == 0)
int result;
printf("Select:%3d wireless, Waiting...\\r\\n", i+1);
//拷贝要连接的热点信息
WifiDeviceConfig select_ap_config = 0;
strcpy(select_ap_config.ssid, info[i].ssid);
strcpy(select_ap_config.preSharedKey, psk);
select_ap_config.securityType = SELECT_WIFI_SECURITYTYPE;
if (AddDeviceConfig(&select_ap_config, &result) == WIFI_SUCCESS)
if (ConnectTo(result) == WIFI_SUCCESS && WaitConnectResult() == 1)
printf("WiFi connect succeed!\\r\\n");
g_lwip_netif = netifapi_netif_find(SELECT_WLAN_PORT);
break;
if(i == ssid_count-1)
printf("ERROR: No wifi as expected\\r\\n");
while(1) osDelay(100);
//启动DHCP
if (g_lwip_netif)
dhcp_start(g_lwip_netif);
printf("begain to dhcp\\r\\n");
//等待DHCP
for(;;)
if(dhcp_is_bound(g_lwip_netif) == ERR_OK)
printf("<-- DHCP state:OK -->\\r\\n");
//打印获取到的IP信息
netifapi_netif_common(g_lwip_netif, dhcp_clients_info_show, NULL);
break;
printf("<-- DHCP state:Inprogress -->\\r\\n");
osDelay(100);
osDelay(100);
return 0;
static void WiFiInit(void)
printf("<--Wifi Init-->\\r\\n");
g_wifiEventHandler.OnWifiScanStateChanged = OnWifiScanStateChangedHandler;
g_wifiEventHandler.OnWifiConnectionChanged = OnWifiConnectionChangedHandler;
g_wifiEventHandler.OnHotspotStaJoin = OnHotspotStaJoinHandler;
g_wifiEventHandler.OnHotspotStaLeave = OnHotspotStaLeaveHandler;
g_wifiEventHandler.OnHotspotStateChanged = OnHotspotStateChangedHandler;
error = RegisterWifiEvent(&g_wifiEventHandler);
if (error != WIFI_SUCCESS)
printf("register wifi event fail!\\r\\n");
else
printf("register wifi event succeed!\\r\\n");
static void OnWifiScanStateChangedHandler(int state, int size)
if (size > 0)
ssid_count = size;
g_staScanSuccess = 1;
printf("callback function for wifi scan:%d, %d\\r\\n", state, size);
return;
static void OnWifiConnectionChangedHandler(int state, WifiLinkedInfo *info)
if (info == NULL)
printf("WifiConnectionChanged:info is null, stat is %d.\\n", state);
else
if (state == WIFI_STATE_AVALIABLE)
g_ConnectSuccess = 1;
else
g_ConnectSuccess = 0;
static void OnHotspotStaJoinHandler(StationInfo *info)
(void)info;
printf("STA join AP\\n");
return;
static void OnHotspotStaLeaveHandler(StationInfo *info)
(void)info;
printf("HotspotStaLeave:info is null.\\n");
return;
static void OnHotspotStateChangedHandler(int state)
printf("HotspotStateChanged:state is %d.\\n", state);
return;
static void WaitSacnResult(void)
int scanTimeout = DEF_TIMEOUT;
while (scanTimeout > 0)
sleep(ONE_SECOND);
scanTimeout--;
if (g_staScanSuccess == 1)
printf("WaitSacnResult:wait success[%d]s\\n", (DEF_TIMEOUT - scanTimeout));
break;
if (scanTimeout <= 0)
printf("WaitSacnResult:timeout!\\n");
static int WaitConnectResult(void)
int ConnectTimeout = DEF_TIMEOUT;
while (ConnectTimeout > 0)
sleep(ONE_SECOND);
ConnectTimeout--;
if (g_ConnectSuccess == 1)
printf("WaitConnectResult:wait success[%d]s\\n", (DEF_TIMEOUT - ConnectTimeout));
break;
if (ConnectTimeout <= 0)
printf("WaitConnectResult:timeout!\\n");
return 0;
return 1;
wifi_connect.h
#ifndef __WIFI_CONNECT_H__
#define __WIFI_CONNECT_H__
int WifiConnect(const char *ssid,const char *psk);
#endif /* __WIFI_CONNECT_H__ */
四、完整代码
编译时在业务BUILD.gn中包含路径
static_library("myapp")
sources = [
"wifi_connect.c",
"hello_world.c"
]
cflags = [ "-Wno-unused-variable" ]
cflags += [ "-Wno-unused-but-set-variable" ]
cflags += [ "-Wno-unused-parameter" ]
include_dirs = [
"//utils/native/lite/include",
"//kernel/liteos_m/components/cmsis/2.0",
"//base/iot_hardware/interfaces/kits/wifiiot_lite",
"//foundation/communication/interfaces/kits/wifi_lite/wifiservice",
"//vendor/hisi/hi3861/hi3861/third_party/lwip_sack/include/",
]
hello_world.c
#include <stdio.h>
#include <unistd.h>
#include "ohos_init.h"
#include "cmsis_os2.h"
#include "wifi_device.h"
#include "lwip/netifapi.h"
#include "lwip/api_shell.h"
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include "lwip/sockets.h"
#include "wifi_connect.h"
#define TCP_SERVER_ADRESS "192.168.31.170" // 要连接TCP服务器地址
#define TCP_PORT 8888 // 要连接TCP服务器端口号
#define WIFI_SSID "test"
#define WIFI_PASSWORD "12345678"
//在sock_fd 进行监听，在 new_fd 接收新的链接
int sock_fd;
int ret;
int addr_length;
static const char *send_data = "Hello! I'm BearPi-HM_Nano TCP Client!\\r\\n";
static void TCPClientTask(void)
//服务器的地址信息
struct sockaddr_in send_addr;
socklen_t addr_length = sizeof(send_addr);
char recvBuf[512];
//连接Wifi
WifiConnect(WIFI_SSID, WIFI_PASSWORD);
//创建socket
if ((sock_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
perror("create socket failed!\\r\\n");
exit(1);
//初始化预连接的服务端地址
send_addr.sin_family = AF_INET;
send_addr.sin_port = htons(TCP_PORT);
send_addr.sin_addr.s_addr = inet_addr(TCP_SERVER_ADRESS);
addr_length = sizeof(send_addr);
connect(sock_fd, (struct sockaddr *)&send_addr, addr_length);
//总计发送 count 次数据
while (1)
bzero(recvBuf, sizeof(recvBuf));
//发送数据到服务远端
if((ret = send(sock_fd, send_data, strlen(send_data), 0)) == -1)
perror("send:");
//接收服务端返回的字符串
if((ret = recv(sock_fd, recvBuf, sizeof(recvBuf), 0)) == -1)
printf("recv error\\r\\n");
printf("recv:%s\\r\\n", recvBuf);
//关闭这个 socket
closesocket(sock_fd);
static void TCPClientDemo(void)
osThreadAttr_t attr;
attr.name = "TCPClientTask";
attr.attr_bits = 0U;
attr.以上是关于HI3861学习笔记（20）——TCP客户端的主要内容，如果未能解决你的问题，请参考以下文章