Question

我正在写一个多线程服务器，我怎么试过调试这个但是由于某种原因它实际上并没有进入由pthread_create（），main的底部调用的客户端线程。知道pthread_create（）失败的原因吗？

此外，我想知道将结构发送到客户端并且客户端将结构作为服务器和客户端之间的主要通信发送回服务器是否是个好主意？或者send（）和recv（）是否是更好的实现方式？

int main(int argc, char* argv[])
{
    int fdServer;
    int accept_fd;
    int optVal = 1;
    struct sockaddr_in fromAddr;
    struct sockaddr_in serverAddr;
    struct pollfd* pServerPollFd;
    pthread_t threadId;
    socklen_t fromAddrSize;

    /*
     * Check user input and assign values
     */
    if(argc != 4)
        errorServer(WRONG_CLI);
    char* greeting = calloc(100,sizeof(char*));
    char* file_name = calloc(100,sizeof(char*));
    greeting = argv[2];
    file_name = argv[3];

    /*
     * Check pthread_key_create != 0 -> ERROR
     */
    if(pthread_key_create(&threadSpecificKey, dataDestructor))
        errorServer(SYSTEM_ERROR);
    int port_num = atoi(argv[1]);
    if(!((port_num <= 65535)&&(1<=port_num)))
        errorServer(INVALID_PORT);

    /*
     * Set up the server socket
     */
    fdServer = socket(AF_INET, SOCK_STREAM, 0);
    if(fdServer < 0)
        errorServer(SYSTEM_ERROR);
    if(setsockopt(fdServer, SOL_SOCKET, SO_REUSEADDR, &optVal, sizeof(int)) < 0)
        errorServer(SYSTEM_ERROR);
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(port_num);
    serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    if(bind(fdServer, (struct sockaddr*)&serverAddr, sizeof(struct sockaddr_in)) < 0)
        errorServer(PORT_ERROR);

    /*
     * Setup poll pool
     */
    pMessageBuffer = fifo_buffer_create(-1);
    poll_pool* pPool = poll_pool_create(MAX_CONNECTIONS + 1);
    pServerPollFd = poll_pool_allocate(pPool, fdServer);
    pServerPollFd->events |= POLLIN;
    int flags = fcntl(fdServer, F_GETFL);// Get the file access mode and the file status flags;
    if(fcntl(fdServer, F_SETFL, flags | O_NONBLOCK) == -1)// Set the file descriptor flags to the value specified by 3rd arg.
            errorServer(SYSTEM_ERROR);
    if(listen(fdServer, 4) != 0)//Allow only 4 connections to the server
            errorServer(SYSTEM_ERROR);




    while(1) {

            fromAddrSize = sizeof(struct sockaddr_in);
        /* Block, waiting for a connection request to come in and accept it.
         * fromAddr structure will get populated with the address of the client
         */
            while((accept_fd = accept(fdServer, (struct sockaddr*)&fromAddr,  &fromAddrSize)) != -1){
                printf("Someone connected \n");

            client_connection *pClientConnection = client_connection_create(accept_fd);
            client_details *pClientDetails = client_details_create();
            client_session *pClientSession = client_session_create(pClientConnection,pClientDetails);

            pthread_mutex_lock(&game_state_mutex);
            //SEARCH THE LINKEDLIST FOR THE GAME NAME - IF FALSE CREATE NEW LINKED ELEMENT
            C_lst requestedGame;
            clst_init(&requestedGame,NULL);
            clst_insert_next(&requestedGame,NULL,pClientSession);

            pthread_mutex_unlock(&game_state_mutex);
            write(accept_fd, greeting, strlen(greeting));



        /* Start a thread to deal with client communication - pass the
         * connected file descriptor as the last argument.
         */
            pthread_create(&threadId, NULL, client_thread, (void*)pClientSession);
            pthread_detach(threadId);
            }

    }
    free(greeting);
    free(file_name);
    return 0;
}

这是client_thread的开头

void * client_thread(void* arg)
    {
    ssize_t numBytesRead;
    char buffer[MAXBUFFER];
    client_session* pClientSession = (client_session*)arg;

    if(pthread_setspecific(threadSpecificKey, pClientSession))
        errorServer(SYSTEM_ERROR);
/* below read fails because of the nonblocking fdServer from fnctl*/
 while((numBytesRead = read(fd,buffer,MAXBUFFER))>0){ 
    //loop code here
   }

Answer 1

为什么没有检查pthread_create返回值而没有打印相应的错误消息？

s = pthread_create(...);
if (s != 0) {
    errno = s;
    perror("pthread_create");
    exit(EXIT_FAILURE);
}

来源：pthread_create（3）

UPD。此外，对于套接字设置，您可以尝试getaddrinfo（3）而不是手动完成所有操作：http://www.beej.us/guide/bgnet/output/html/multipage/syscalls.html#getaddrinfo

UPD 2.'发送结构'是什么意思？

C - 服务器客户端多线程pthread_create失败

1 个答案: