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AT设备udp组播问题

发布于 2022-12-27 16:47:54 浏览：635 订阅该版

请问AT设备，支持通过SAL使用组播功能吗？逛了一圈论坛实现好像底层都是lwip的。
使用esp8266模块，setsockopt时报错显示不支持操作，看了一下好像是atsocket没实现相关操作？

日志如下所示
```c
msh />bing_test esp0
socket bind network interface device(esp0) success!
[E/at.skt] AT socket (0) not support option level : 0.
setsockopt failed !
msh />
```

测试代码如下：

```c
#include <rtthread.h>
#include <arpa/inet.h>
#include <netdev.h>
#define SERVER_PORT   8888
static int bing_test(int argc, char **argv)
{
    struct sockaddr_in client_addr;
    struct sockaddr_in server_addr;
    struct netdev *netdev = RT_NULL;
    int sockfd = -1;

if (argc != 2)
    {
        rt_kprintf("bind_test [netdev_name]  --bind network interface device by name.\n");
        return -RT_ERROR;
    }

/* 通过名称获取 netdev 网卡对象 */
    netdev = netdev_get_by_name(argv[1]);
    if (netdev == RT_NULL)
    {
        rt_kprintf("get network interface device(%s) failed.\n", argv[1]);
        return -RT_ERROR;
    }

// 多播 IP 地址
    char muticast_addr[16] = "239.255.0.1";
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
    {
        rt_kprintf("Socket create failed.\n");
        return -RT_ERROR;
    }

/* 初始化需要绑定的客户端地址 */
    client_addr.sin_family = AF_INET;
    client_addr.sin_port = htons(SERVER_PORT);//change

/* 获取网卡对象中 IP 地址信息 */
    client_addr.sin_addr.s_addr = netdev->ip_addr.addr;
    rt_memset(&(client_addr.sin_zero), 0, sizeof(client_addr.sin_zero));

if (bind(sockfd, (struct sockaddr *)&client_addr, sizeof(struct sockaddr)) < 0)
    {
        rt_kprintf("socket bind failed.\n");
        closesocket(sockfd);
        return -RT_ERROR;
    }
    rt_kprintf("socket bind network interface device(%s) success!\n", netdev->name);

// 多播地址结构体
    struct ip_mreq mreq;
    mreq.imr_multiaddr.s_addr=inet_addr(muticast_addr); /*<! 多播组 IP 地址设置 */
    mreq.imr_interface.s_addr = htonl(INADDR_ANY); /*<! 待加入多播组的 IP 地址 */

// 添加多播组成员（该语句之前，socket 只与 某单播IP地址相关联 执行该语句后 将与多播地址相关联）
    int ret = setsockopt(sockfd,IPPROTO_IP,IP_ADD_MEMBERSHIP,&mreq,sizeof(mreq));
    if(ret < 0)
    {
        rt_kprintf("setsockopt failed !");
        return;
    }
    else
    {
        rt_kprintf("setsockopt success\n");
    }

char buf[1024];
    int length=0;
    struct sockaddr_in sender;
    int sender_len=sizeof(sender);
    while(1)
    {
        memset(buf, 0, sizeof(buf));
        length = recvfrom(sockfd,buf,sizeof(buf),0,(struct sockaddr*)&sender,(socklen_t *)&sender_len);
        buf[length]='\0';
        rt_kprintf("%s %d : %s\n", inet_ntoa(sender.sin_addr), ntohs(sender.sin_port), buf);
    }
    setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP,&mreq, sizeof(mreq));
    closesocket(sockfd);

return RT_EOK;
}

#ifdef FINSH_USING_MSH
#include <finsh.h>
MSH_CMD_EXPORT(bing_test, bind network interface device test);
#endif /* FINSH_USING_MSH */
```

```c
int at_getsockopt(int socket, int level, int optname, void *optval, socklen_t *optlen)
{
    struct at_socket *sock;
    int32_t timeout;

if (optval == RT_NULL || optlen == RT_NULL)
    {
        LOG_E("AT getsocketopt input option value or option length error!");
        return -1;
    }

sock = at_get_socket(socket);
    if (sock == RT_NULL)
    {
        return -1;
    }

switch (level)
    {
    case SOL_SOCKET:
        switch (optname)
        {
        case SO_RCVTIMEO:
            timeout = sock->recv_timeout;
            ((struct timeval *)(optval))->tv_sec = (timeout) / 1000U;
            ((struct timeval *)(optval))->tv_usec = (timeout % 1000U) * 1000U;
            break;

case SO_SNDTIMEO:
            timeout = sock->send_timeout;
            ((struct timeval *) optval)->tv_sec = timeout / 1000U;
            ((struct timeval *) optval)->tv_usec = (timeout % 1000U) * 1000U;
            break;

default:
            LOG_E("AT socket (%d) not support option name : %d.", socket, optname);
            return -1;
        }
        break;

default:
        LOG_E("AT socket (%d) not support option level : %d.", socket, level);
        return -1;
    }

return 0;
}
```