Question

我正在尝试使用线程在Linux中实现客户端服务器聊天，但是会遇到奇怪的行为。我正在尝试从客户端获取消息到缓冲区，然后将消息发送给他，但我只收到消息，消息不会发送回客户端。可能是什么原因？？代码说明：我正在为服务器打开一个FIFO，以便其他客户端可以使用特殊消息连接到它。为此，我创建了一个只执行此任务的线程。客户端连接后，我正在与客户端通过2个FIFO进行通信：一个用于传入消息，一个用于传出消息。现在我尝试做的是从已连接到服务器的客户端获取消息，然后使用两个线程将其发送回给他，每个线程用于写入或读取目的，但我只能成功从客户端获取消息，但客户无法取回它。可能是什么问题？非常感谢你提前！

来源附件。

#include <unistd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <pthread.h>

#define MAX_MESSAGE_LENGHT 10240

void server_signal_handler();
void *server_fifo_read_thread(int id);
void *server_fifo_write_thread(int id);
void *server_main_fifo_connection();
char mess_buffer[1000];
int main() {

    char server_fifo_path[] = "/tmp/server-fifo";

    int server_fifo = mkfifo(server_fifo_path, 0666);
    if (server_fifo < 0) {
        printf("Error creating server fifo\n");
        return -1;
    }
    server_fifo = open(server_fifo_path, O_RDONLY);
    if (server_fifo < 0) {
        printf("Error opening file");
        return -1;
    }   

    pthread_t server_main_fifo_thread;
    pthread_create(&server_main_fifo_thread, NULL, server_main_fifo_connection, (int*)server_fifo);
    pthread_join(server_main_fifo_thread, NULL);
}


void *server_main_fifo_connection(int server_fifo){
    while (1){          
        char buffer[MAX_MESSAGE_LENGHT];
        while (read(server_fifo, buffer, MAX_MESSAGE_LENGHT) == 0); // Wait for client initial message

        int message_length = *((int*)buffer);
        int client_id = *( (int*)(buffer + sizeof(int)) );
        char* client_name = (char*)malloc(sizeof(char) * (message_length + 1));
        memcpy(client_name, buffer + 2*sizeof(int), message_length);
        client_name[message_length+1] = '\0'; 
        pthread_t write_thread;
        pthread_create(&write_thread, NULL, server_fifo_write_thread, (int*)client_id);

    }
}

void *server_fifo_write_thread(int id){
    int write_fifo;
    char fifo_write_path[20];
    sprintf(fifo_write_path, "/tmp/fifo-%d-in", id);
    write_fifo = open(fifo_write_path, O_WRONLY);
    if (write_fifo < 0){
        printf("Error opening write FIFO");
        return;
    }
    pthread_t read_thread;
    pthread_create(&read_thread, NULL, server_fifo_read_thread, (int*)id);
    write(write_fifo, "/ack", 5);
    while(1){
        write(write_fifo, mess_buffer, strlen(mess_buffer));
    }

}

void *server_fifo_read_thread(int id){
    int read_fifo;
    char fifo_read_path[20];
    sprintf(fifo_read_path, "/tmp/fifo-%d-out", id);
    read_fifo = open(fifo_read_path, O_RDONLY);
    if (read_fifo < 0){
        printf("Error opening read FIFO");
        return;
    }
    while(1){
        while (read(read_fifo, mess_buffer, strlen(mess_buffer)) == 0);
    }
}

使用线程在Linux中进行客户端/服务器聊

0 个答案: