Question

我写了一个简单的程序，它应该发送长度不断变化的UDP包。 UDP数据包的大小可以随时更改。用户可以通过命令行输入端口号以及消息的最小和最大长度。在有效载荷的前32位是UDP包号。我使用sendto（）函数，我收到一个有效的返回号码但是当我尝试使用UDP服务器程序（例如SocketTest）验证它时，我无法在另一端看到任何数据。以下是我的代码：

#define DEFAULT_PORT 355

int   Port = DEFAULT_PORT;          // Port to send data to
int Max_Length = 100, Min_Length = 8; //default values
static const char alphanum[] =
    "0123456789"
    "!@#$%^&*"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "abcdefghijklmnopqrstuvwxyz";
int stringLength = sizeof(alphanum);

char genRandom()
{
    return alphanum[rand() % stringLength];
}

void usage()
{
    cout << "-m:int Define minimum UDP packet size" << endl;
    cout << " -M:int Define maximum UDP packet size" << endl;
    cout << " -p:int Define remote port" << endl;

}

void ValidateArgs(int argc, char **argv)
{
    int i;

    for (i = 1; i < argc; i++)
    {
        if ((argv[i][0] == '-'))
        {
            switch (argv[i][1])
            {
            case 'm':
                if (strlen(argv[i]) > 3) {
                    Min_Length = (double)atoi(&argv[i][3]);
                }
                break;
            case 'M':
                if (strlen(argv[i]) > 3) {
                    Max_Length = (double)atoi(&argv[i][3]);
                }
                break;
            case 'p':
                if (strlen(argv[i]) > 3) {
                    Port = atoi(&argv[i][3]);
                }                   
                break;
            default:
                usage();
                break;
            }
        }
    }
}
int main(int argc, char **argv)
{
    sockaddr_in my_addr;
    ValidateArgs(argc, argv);
    WSADATA wsd;
    int Result = WSAStartup(MAKEWORD(2, 2), &wsd);
    if (Result != NOERROR) {
        cout << "WSAStartup Failed!" << endl;
        exit(0);
    }
    SOCKET sock;
    sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (sock == INVALID_SOCKET) {
        cout << "Socket Failer with error: " << WSAGetLastError() << endl;
        WSACleanup();
        exit(1);
    }

    my_addr.sin_family = AF_INET;
    my_addr.sin_addr.s_addr = inet_addr("192.68.0.31");
    my_addr.sin_port = htons((short)Port);
    string data = "";
    /*Get a Random String Length*/
    random_device seeder;
    int UDP_Packet_number = 1;
    string buffer_data;
    mt19937 engine(seeder());
    uniform_int_distribution<int> dist(Min_Length, Max_Length);// user input from command line
    int StrLen = dist(engine);
    while (true) {
        /*Get aRandom String*/
        for (int i = 0; i < StrLen; ++i)
        {
            data += genRandom();

        }
        srand(time(0));
        StrLen = dist(engine);
        char numbr_pkg[4];
        numbr_pkg[0] = (UDP_Packet_number >> 24) & 0xff;
        numbr_pkg[1] = (UDP_Packet_number >> 16) & 0xff;
        numbr_pkg[2] = (UDP_Packet_number >> 8) & 0xff;
        numbr_pkg[3] = UDP_Packet_number & 0xff;
        /*First 32 Bits is the packet Number*/
        for (int i = 0; i < 4; i++) {
            buffer_data += numbr_pkg[i];
        }       

        buffer_data += data;
        data = "";
        int result = sendto(sock, buffer_data.c_str(), buffer_data.length(), 0, (SOCKADDR *)&my_addr, sizeof(my_addr));
        //cout << result << "  " << buffer_data.length() << endl;
        buffer_data = "";
        UDP_Packet_number++;

    }
    return 0;
}

你能告诉我我做错了什么吗？我想找很长时间的解决方案。

UDP Sender程序验证

0 个答案: