chat.c

个人精心原创linux下开发的聊天小程序

/*linux下编写聊天软件非常简单，创建服务后，
再创建两个线程进行收发就可以了。下面把我的简单代码贴出供大家参考。*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <errno.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <sys/types.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
struct sockaddr_in client_addr;
int sock;
socklen_t addr_len;
sem_t send_sem;
char send_message_buffer[128];
void *recv_message(void *arg)
{
    char buffer[128];
    int len;
    while(1)
    {
        len = recvfrom(sock, buffer, sizeof(buffer) - 1, 0,(struct sockaddr *) &client_addr, &addr_len);
        if (len < 0)
        {
            perror("recieve data failure");
        }
        buffer[len] = '\0';
        printf("-----recieve data-----\n");
        printf("come from %s:%d message:%s\n",inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port), buffer);
    }
}
void *send_message(void *arg)
{
    int len;
    while(1)
    {
        sem_wait(&send_sem);
        len = sendto(sock, send_message_buffer, strlen(send_message_buffer), 0,(struct sockaddr *) &client_addr, addr_len);
        if (len < 0)
        {
            printf("\nsend data failure\n");
        }
        printf("-----send data-----\n");
        printf("send message:%s to %s:%d\n",send_message_buffer,inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
    }
}
int main(int argc, char **argv)
{
    struct sockaddr_in server_addr;
    int stdin_fd;
    int len;
    int res;
    char ip_address[128];
    char buffer[128];
    int port_number;
    pthread_t recv_thread,send_thread;
    pthread_attr_t thread_attr;
    /* 创建 socket , 关键在于这个 SOCK_DGRAM */
    if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
    {
        perror("create socket error");
        exit(errno);
    } 
    else
    {
        printf("create socket success\n");
    }
    memset(&server_addr, 0, sizeof(struct sockaddr_in));
    /* 设置地址和端口信息 */
    server_addr.sin_family = AF_INET;
    if (argv[2])
    {
        server_addr.sin_port = htons(atoi(argv[2]));
    }
    else
    {
        server_addr.sin_port = htons(6666);
    }
    if (argv[1])
    {
        server_addr.sin_addr.s_addr = inet_addr(argv[1]);
    }
    else
    {
        server_addr.sin_addr.s_addr = INADDR_ANY;
    }
    /* 绑定地址和端口信息 */
    if ((bind(sock, (struct sockaddr *) &server_addr, sizeof(server_addr))) == -1) 
    {
        perror("bind port failure\n");
        exit(errno);
    }
    else
    {
        printf("bind port success\n");
    }
    printf("input ip you want to connect:");
    gets(ip_address);
    printf("input port:");
    gets(buffer);
    port_number=atoi(buffer);
    client_addr.sin_addr.s_addr = inet_addr(ip_address);//处理IP地址邋inet_addr
    client_addr.sin_port = htons(port_number);//处理端口号atoi和htons
    stdin_fd=open("/dev/stdin",O_RDWR);//stdin标准输入流
    if(stdin_fd==-1)
    {
        printf("open stdin failure\n");
        close(sock);
        return -1;
    }
    /* 循环接收数据 */
    addr_len = sizeof(client_addr);
    res=sem_init(&send_sem,0,0); /*初始化信号量*/
        if(res!=0)
    {
        perror("initual signal failure\n");
        exit(EXIT_FAILURE);
    }    
    res=pthread_attr_init(&thread_attr); /*设置属性为脱离状态*/
    if(res!=0)
    {
        perror("initial thread property error\n");
        exit(EXIT_FAILURE);
    }
    res=pthread_attr_setdetachstate(&thread_attr,PTHREAD_CREATE_DETACHED);/*设置属性为脱离状态::即不等待子线程的返回值*/
    if(res!=0)
    {
        perror("create thread property failure\n");
        exit(EXIT_FAILURE);
    }
    res=pthread_create(&recv_thread,&thread_attr,recv_message,NULL); /*调用发送函数*/
    if(res!=0)
    {
        perror("create recv_thread failure\n");
        exit(EXIT_FAILURE);
    }
    res=pthread_create(&send_thread,&thread_attr,send_message,NULL); /*调用发送函数*/
    if(res!=0)
    {
        perror("create send_thread failure\n");
        exit(EXIT_FAILURE);
    }
    while (1)
    {
        len=read(stdin_fd, send_message_buffer,128);
        send_message_buffer[len-1] = '\0';
            sem_post(&send_sem);
        //printf("data send!\n");
    }
    return 0;
}