ESP32 TCP sock长连接 断线重连

wifi配网代码如下：

#include "freertos/FreeRTOS.h"
#include "esp_wifi.h"
#include "esp_system.h"
#include "esp_event.h"
#include "esp_event_loop.h"
#include "nvs_flash.h"
#include "driver/gpio.h"
#include "wifi_tcp.h"

#define CONFIG_ESP_WIFI_SSID "jack"
#define CONFIG_ESP_WIFI_PASSWORD         "jack.12306"

static esp_err_t wifi_event_handler(void *ctx, system_event_t *event) {
  switch (event->event_id) {
  case SYSTEM_EVENT_STA_START:
    esp_wifi_connect();
    break;
  case SYSTEM_EVENT_STA_GOT_IP:
    tcp_ini_client();
    break;
  case SYSTEM_EVENT_STA_DISCONNECTED:
    esp_wifi_connect();
    break;
  default:
    break;
  }
  return ESP_OK;
}

void app_main(void) {
  nvs_flash_init();
  tcpip_adapter_init();
  ESP_ERROR_CHECK(esp_event_loop_init(wifi_event_handler, NULL));
  wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT()
  ;
  ESP_ERROR_CHECK(esp_wifi_init(&cfg));
  ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
  ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
  wifi_config_t sta_config = { .sta = { .ssid = CONFIG_ESP_WIFI_SSID,
      .password = CONFIG_ESP_WIFI_PASSWORD, .bssid_set = false } };
  ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &sta_config));
  ESP_ERROR_CHECK(esp_wifi_start());
  ESP_ERROR_CHECK(esp_wifi_connect());

}

tcp连接代码如下：
wifi_tcp.h

/*
 * test.h
 *
 *  Created on: 2019年10月19日
 *      Author: Administrator
 */

#ifndef _WIFI_TCP_H_
#define _WIFI_TCP_H_

#include <string.h>
#include <sys/param.h>
#include <sys/socket.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "tcpip_adapter.h"
#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include <lwip/netdb.h>

void tcp_ini_client(void);

#define OPENSSL_DEMO_THREAD_STACK_WORDS 10240
#define OPENSSL_DEMO_THREAD_PRORIOTY    8


#endif /* MAIN_TEST_H_ */

wifi_tcp.c

#include "wifi_tcp.h"
#define HOST_IP_ADDR "192.168.2.188"
#define PORT         3355
int tcpsock = 0;
struct sockaddr_in dest_addr;
TaskHandle_t xtcpRecvTask = NULL;
void tcp_recv_data(void *pvParameters);
xTaskHandle xHandle;
void init_socket() {
  tcpsock = socket(AF_INET, SOCK_STREAM, 0);
  printf("sock:%d\n", tcpsock);
  if (tcpsock < 0) {
    printf("Unable to create socket: errno %d", errno);
    return;
  }
  printf("Socket created, sending to %s:%d", HOST_IP_ADDR, PORT);
  dest_addr.sin_addr.s_addr = inet_addr(HOST_IP_ADDR);
  dest_addr.sin_family = AF_INET;
  dest_addr.sin_port = htons(PORT);
}

void connect_socket(int reConflag) {
  init_socket();
  int err = connect(tcpsock, (struct sockaddr * ) &dest_addr,
      sizeof(dest_addr));
  if (err != 0) {
    printf("Socket unable to connect: errno %d", errno);
    close(tcpsock);
    tcpsock = -1;
    vTaskDelay(3000 / portTICK_PERIOD_MS);
    connect_socket(reConflag);
  } else {
    printf("Successfully connected\n");
    if (!reConflag) {
      xTaskCreate(tcp_recv_data, "tcp_recv_data",
          OPENSSL_DEMO_THREAD_STACK_WORDS, NULL,
          OPENSSL_DEMO_THREAD_PRORIOTY, &xHandle);
    }

  }

}

//周期定时器的回调函数
void tcp_reconnect(int reConflag) {
  printf("zhaoming-------tcp_reconnect-----");
  connect_socket(reConflag);

}

void tcp_recv_data(void *pvParameters) {
  uint8_t rx_buffer[1024] = { 0 };
  while (1) {
    int len = recv(tcpsock, rx_buffer, sizeof(rx_buffer) - 1, 0);
    if (len > 0) {
      rx_buffer[len] = 0; // Null-terminate whatever we received and treat like a string
      printf("Received %d bytes from %s:\n", len, rx_buffer);
//      int err = send(tcpsock, rx_buffer, len, 0);
//      if (err < 0) {
//        printf("Error occurred during sending: errno %d", errno);
//        return;
//      }
//      printf("Message sent");
    } else {
      close(tcpsock);
      tcpsock = -1;
      tcp_reconnect(1);

    }
  }

}

void tcp_ini_client(void) {
  connect_socket(0);
}