채팅방 서버 기본 코드

#include 
#include 

#include 
#include 
#include 
#include 
#include 

#define SER_PORT 3333

struct message
{
    int action;
    char name[20];
    char passwd[10];
    char toname[20];
    char msg[100];
};

struct online
{
    int cfd;
    char name[20];

    struct online *next;
};

struct online *head = NULL;

void insert_user(struct online *new_user)
{
     new_user->next = head;
     head = new_user;
}

int find_fd(char *toname)
{
    if(head == NULL)
    {
        return -1;
    }

    struct online *temp = head;

    while(temp != NULL)
    {
        if(strcmp(temp->name,toname) == 0)
    {
        return temp->cfd;
    }

    temp = temp->next;
    }

    return -1;
}

void * read_msg(void *arg)
{
    int cfd = *((int *)arg);
    struct online *new_user;
    struct message *msg = (struct message *)malloc(sizeof(struct message));

    int n_read;

    while(1)
    {
            n_read = read(cfd,msg,sizeof(struct message));

            if(n_read == 0)
            {
                printf("client is close!
");
            break;
            }

        printf("msg->action = %d
",msg->action);

        switch(msg->action)
        {
            case 1:
            {
                msg->action = 1;

            write(cfd,msg,sizeof(struct message));

            printf("write success!
");
            break;
            }
            case 2:
            {
                         new_user = (struct online *)malloc(sizeof(struct online));

             new_user->cfd = cfd;

             strcpy(new_user->name,msg->name);

             msg->action = 2;

             insert_user(new_user);

             write(cfd,msg,sizeof(struct message));
             break;
            }
            case 3:
            { 
                 int to_fd = find_fd(msg->toname);

             if(to_fd == -1)
             {
                 msg->action = -3;

                 write(cfd,msg,sizeof(struct message));
             }
             else
             {
                 msg->action = 3;

                 write(to_fd,msg,sizeof(struct message));
             }

             break;

            }
        }
    }
}

int main(int argc, char *argv[])
{
    if(argc != 2)
    {
        printf("Please input server bind ip!
");
    exit(1);
    }

    int s_len;
    int sockfd;
    int cfd;
    int pid;
    int n_read;

    int opt = 1;

    pthread_t id;

    char buffer[1024];

    struct message *msg = (struct message *)malloc(sizeof(struct message));

    struct sockaddr_in ser_addr;
    struct sockaddr_in client_addr;

    if((sockfd = socket(AF_INET,SOCK_STREAM,0)) == - 1)
    {
        perror("socket creat error!");
    exit(1);
    }

    printf("sockfd success!
");

    bzero(&ser_addr,sizeof(ser_addr));
    ser_addr.sin_family = AF_INET;
    //ser_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    ser_addr.sin_addr.s_addr = inet_addr(argv[1]);
    ser_addr.sin_port = htons(SER_PORT);

    setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt));

    if(bind(sockfd,(struct sockaddr *)&ser_addr,sizeof(ser_addr)) == -1)
    {
        perror("bind error!");
    exit(1);
    }

    printf("bind success!
");

    if(listen(sockfd,5) == -1)
    {
        perror("listen error!");
    exit(1);
    }

    printf("listen success!
");

    while(1)
    {
        s_len = sizeof(client_addr);
        if((cfd = accept(sockfd,&client_addr,&s_len)) < 0)
        {
            perror("accept error!");
        exit(1);
        }
        printf("accept success = %s
",inet_ntoa(client_addr.sin_addr));

    pthread_create(&id,NULL,read_msg,(void *)&cfd);
  #if 0
    pid = fork();

    if(pid == 0)
    {
        while(1)
        {
            n_read = read(cfd,msg,sizeof(struct message));

            if(n_read == 0)
            {
                printf("client is close!
");
            break;
            }
                printf("recv client send msg:%d %s %s
",msg->action,msg->name,msg->passwd);

            msg->action = -1;

            write(cfd,msg,sizeof(struct message));
             }
    }
    else if(pid > 0)
    {
        ;
        }
 #endif
    }
    return 0;
}