sockets - 绑定(bind)失败并出现无效参数错误

Question

我正在尝试编写一个使用绑定(bind)的简单程序。该代码在Solaris 上编译，但我收到bind() 失败并出现无效参数错误。

我已经尝试了很多次，但都遇到同样的错误，我无法找出错误。

这是代码:

int my_func ()
{
    struct sockaddr_storage name;
    struct addrinfo hints, *res;
    int status;

    char hostnamestr[256];
    gethostname (hostnamestr, 256);

    int iRC;

    memset(&hints, 0, sizeof(hints));

    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;

    if ((status = getaddrinfo(hostnamestr, NULL, &hints, &res) != 0))
    {
        printf("getaddrinfo: %s\n", gai_strerror(status));
        return 1;
    }

    memcpy(&name, res->ai_addr, res->ai_addrlen);
    freeaddrinfo(res);
    monsocket = socket (name.ss_family, SOCK_STREAM, IPPROTO_TCP);
    int iLastError = WSAGetLastError ();

    if (monsocket == -1)
    {
        fprintf (stderr, "cannot open socket for monitors [%s]\n", wsaerror (iLastError));
        return 1;
    }

    sockopts(monsocket);  
    int flags;
    flags = fcntl (monsocket, F_GETFL);
    iLastError = WSAGetLastError ();

    if (flags < 0)
    {
        fprintf (stderr, "cannot get flags for socket [%s]\n", wsaerror (iLastError));
        return 1;
    }

    iRC = fcntl (monsocket, F_SETFL, flags | O_NONBLOCK);
    iLastError = WSAGetLastError ();

    if (iRC == -1)
    {
        fprintf (stderr, "cannot set flags for socket [%s]\n", wsaerror (iLastError));
        return 1;
    }

    int iPort;
    if(name.ss_family == AF_INET)
    {
        ((struct sockaddr_in *) &name)->sin_port = htons (8091);
    }    
    else if(name.ss_family == AF_INET6)
    {
        ((struct sockaddr_in6 *) &name)->sin6_port = htons (8091);
    }

    struct  sockaddr_in* ipv = (struct sockaddr_in *) &name;
    printf("connecting to addr: %s\n", inet_ntoa(ipv->sin_addr));

    iRC = bind (monsocket, (struct sockaddr *) &name, sizeof (name));
    iLastError = WSAGetLastError ();

    if (iRC == -1)
    {
        close(monsocket);
        monsocket=-1;
        fprintf (stderr, "could not bind to port %d\n", iPort);
        printf("Error %s",wsaerror (iLastError));
        return 1;
    }
    else
    {
        fprintf (SCHED_SHOW_MSG, "bound on port %i\n", ntohs (iPort));
    }
    iRC = listen (monsocket, SOMAXCONN);
    iLastError = WSAGetLastError ();

    if (iRC == -1)
    {
        fprintf (stderr, "could not listen to socket [%s]\n", wsaerror (iLastError));
        return 1;
    }

    return 0;
}

Answer 1

bind (monsocket, (struct sockaddr *) &name, sizeof (name))

您的sizeof(name)产生通用sockaddr_storage大小的大小。您需要 sockaddr_in 或 sockaddr_in6 的大小。

无论如何，您最好直接使用 getaddrinfo 中的内容:

monsocket = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
bind(monsocket, res->ai_addr, res->ai_addrlen);

为此，您必须移动 freeaddrinfo(res) 调用。