前言

1. 使用两个线程作为客户端中的收和发
2. 使用线程挂起和线程恢复的api来实现
3. 接收线程必须要保证在处理连接状态才能进行接收。

Demo

//
// Created by shchl on 2024/3/8.
//
#include <string.h>
#include "lwip/api.h"
#include "FreeRTOS.h"
#include "task.h"#define TCP_CLIENT_RX_BUFSIZE 256static void tcp_client_send(void *);static void tcp_client_rec(void *);static TaskHandle_t client_send_handle;
static TaskHandle_t client_rec_handle;
static ip_addr_t server_ipaddr, loca_ipaddr;
static uint16_t server_port = 8080;
static struct netconn *tcp_conn;
static uint8_t tcp_client_recvbuf[TCP_CLIENT_RX_BUFSIZE] = {0};    //TCP客户端接收数据缓冲区void create_netconn_tcp_client_thread() {xTaskCreate((TaskFunction_t) tcp_client_send,(const char *) "tcp_client_send",(uint16_t) 256,(void *) NULL,(UBaseType_t) 10,(TaskHandle_t *) &client_send_handle);xTaskCreate((TaskFunction_t) tcp_client_rec,(const char *) "tcp_client_rec",(uint16_t) 256,(void *) NULL,(UBaseType_t) 11,(TaskHandle_t *) &client_rec_handle);}const char *tcp_client_sendbuf = "Apollo STM32F4/F7 NETCONN TCP Client send data\r\n";    //TCP客户端发送数据缓冲区
static void tcp_client_send(void *arg) {err_t err, recv_err;IP4_ADDR(&server_ipaddr, 192, 168, 8, 2);while (1) {tcp_conn = netconn_new(NETCONN_TCP);  //创建一个TCP链接err = netconn_connect(tcp_conn, &server_ipaddr, server_port);//连接服务器if (err != ERR_OK) {netconn_delete(tcp_conn); //返回值不等于ERR_OK,删除tcp_clientconn连接printf("连接失败....等待重新连接\r\n");vTaskDelay(1000);continue;} else {vTaskResume(client_rec_handle);/*恢复接收线程*/printf("连接...ok\r\n");}while (1) {err = netconn_write(tcp_conn, tcp_client_sendbuf, strlen((char *) tcp_client_sendbuf),NETCONN_COPY); //发送tcp_server_sentbuf中的数据if (err != ERR_OK) {printf("发送失败\r\n");netconn_close(tcp_conn);netconn_delete(tcp_conn);break;}vTaskDelay(1000);}}
}static void tcp_client_rec(void *arg) {err_t recv_err;uint32_t data_len;struct pbuf *q;struct netbuf *recvbuf;vTaskSuspend(client_rec_handle); /*挂起自身线程*/while (1) {if ((recv_err = netconn_recv(tcp_conn, &recvbuf)) == ERR_OK)  //接收到数据{portDISABLE_INTERRUPTS(); //关中断memset(tcp_client_recvbuf, 0, TCP_CLIENT_RX_BUFSIZE);  //数据接收缓冲区清零for (q = recvbuf->p; q != NULL; q = q->next)  //遍历完整个pbuf链表{//判断要拷贝到TCP_CLIENT_RX_BUFSIZE中的数据是否大于TCP_CLIENT_RX_BUFSIZE的剩余空间，如果大于//的话就只拷贝TCP_CLIENT_RX_BUFSIZE中剩余长度的数据，否则的话就拷贝所有的数据if (q->len > (TCP_CLIENT_RX_BUFSIZE - data_len))memcpy(tcp_client_recvbuf + data_len, q->payload, (TCP_CLIENT_RX_BUFSIZE - data_len));//拷贝数据else memcpy(tcp_client_recvbuf + data_len, q->payload, q->len);data_len += q->len;if (data_len > TCP_CLIENT_RX_BUFSIZE) break; //超出TCP客户端接收数组,跳出}portENABLE_INTERRUPTS(); //关中断data_len = 0;  //复制完成后data_len要清零。printf("%s", tcp_client_recvbuf);netbuf_delete(recvbuf);} else if (recv_err == ERR_CLSD)  //关闭连接{printf("服务器%d.%d.%d.%d断开连接\r\n", 192, 168, 8, 2);vTaskSuspend(client_rec_handle); /*挂起自身线程*/}}
}