Function tcpserv

examples/network/tcpserver.c:44–223

* @brief This function is for creating a tcp server on RT-Thread */

* @brief  This function is for creating a tcp server on RT-Thread
*/
static void tcpserv(void *arg)
{
    int ret;
    char *recv_data; /* recv_data is a pointer used to receive data */ /* 用于接收的指针，后面会做一次动态分配以请求可用内存 */
    int sock, connected, bytes_received;
    struct sockaddr_in server_addr, client_addr;

    struct timeval timeout;
    fd_set readset, readset_c;
    socklen_t sin_size = sizeof(struct sockaddr_in);

    recv_data = rt_malloc(BUFSZ + 1);/* Allocate space for recv_data */ /* 分配接收用的数据缓冲 */
    if (recv_data == RT_NULL)
    {
        LOG_E("No memory");
        return;
    }
    /* Before making use of  socket, socket should be created first and set the socket created to SOCK_STREAM(TCP) */
    /* 一个socket在使用前，需要预先创建出来，指定SOCK_STREAM为TCP的socket */
    if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1)
    {
        LOG_E("Create socket error");
        goto __exit;
    }
    /* Initialize server side address */
    /* 初始化服务端地址 */
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(port); /*Server side port number*//* 服务端工作的端口 */
    server_addr.sin_addr.s_addr = INADDR_ANY;
    rt_memset(&(server_addr.sin_zero), 0x0, sizeof(server_addr.sin_zero));
    /* Bind socket to server side address */
    /* 绑定socket到服务端地址 */
    if (bind(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)) == -1)
    {
        LOG_E("Unable to bind");
        goto __exit;
    }
    /* Listen on socket */
    /* 在socket上进行监听 */
    if (listen(sock, 10) == -1)
    {
        LOG_E("Listen error");
        goto __exit;
    }

    LOG_I("\nTCPServer Waiting for client on port %d...\n", port);

    started = 1;
    is_running = 1;

    timeout.tv_sec = 3;
    timeout.tv_usec = 0;

    while (is_running)
    {
        FD_ZERO(&readset);
        FD_SET(sock, &readset);