#ifndef _DEBUG_H_
#define _DEBUG_H_

/*
	__FILE__:输出文件名
	__FUNCTION__:输出函数名
	__LINE__:输出行号
    }while：括号要与while连接在一起
 */
#define DEBUG_INFO(args...) do{ \
    char b__[1024];\
    sprintf(b__,args);\
    fprintf(stderr,"[%s,%s,%d] : %s", __FILE__ , __FUNCTION__ ,__LINE__ ,b__); \
}while(0)
#endif
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#ifndef __TCP_SOCKET_H_
#define __TCP_SOCKET_H_

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>         /* See NOTES */
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>

// 创建并初始化 tcp 服务器 socket
extern int create_tcp_server_socket(const char *ip,unsigned short port);

// 用于创建tcp客户端连接
extern int create_tcp_client_socket(const char *server_ip,unsigned short server_port);
//等待与客户端连接
extern int wait_for_connect(int sockfd, struct sockaddr_in* client_addr);
#endif

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#include "tcp_socket.h"
#include "debug.h"

#define BACKLOG 10
int create_tcp_server_socket(const char *ip,unsigned short port)
{
    int sfd;
    int ret;
    struct sockaddr_in server_addr;
    socklen_t len = sizeof(struct sockaddr_in);
    
    //1、创建套接字
    sfd = socket(AF_INET, SOCK_STREAM, 0);
    if(sfd == -1)
    {
        DEBUG_INFO("[ERROR] socket:%s\n", strerror(errno));
        return -1;
    }
    
    bzero(&server_addr, len);
    //地址族/协议族  与socket函数第一个参数相同
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(port);
    server_addr.sin_addr.s_addr = inet_addr(ip); 

    //2、绑定ip，端口号
    ret = bind(sfd, (const struct sockaddr *) &server_addr, len);
    if(ret == -1)
    {
        DEBUG_INFO("[ERROR] bind():%s\n", strerror(errno));
        return -1;
    }
    
    //3、设置套接字为监听状态，建立监听队列，如果服务端处理不过来的话，会把客户端连接请求缓存在监听队列里，如果超过最大队列数量，那么会被拒绝连接
    ret = listen(sfd, BACKLOG); 
    if(ret == -1)
    {
        DEBUG_INFO("[ERROR] listen():%s\n", strerror(errno));
        return -1;
    }

    return sfd;
}


int create_tcp_client_socket(const char *server_ip,unsigned short server_port)
{
    int sfd;
    int ret;
    struct sockaddr_in server_addr;

    //1、创建套接字
    sfd = socket(AF_INET, SOCK_STREAM, 0);
    if(sfd == -1)
    {
        DEBUG_INFO("[ERROR] socket():%s\n", strerror(errno));
        return -1;
    }
    
    bzero(&server_addr, sizeof(struct sockaddr_in));
    //地址族/协议族  与socket函数第一个参数相同
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(server_port);
    server_addr.sin_addr.s_addr = inet_addr(server_ip); 

    ret = connect(sfd, (const struct sockaddr *) &server_addr, sizeof(struct sockaddr_in));
    if(ret == -1)
    {
        DEBUG_INFO("[ERROR] connect():%s\n", strerror(errno));
        return -1;
    }

    return sfd;
}


int wait_for_connect(int sockfd, struct sockaddr_in* client_addr)
{
    int cfd;
    socklen_t len = sizeof(struct sockaddr_in);
    cfd = accept(sockfd, (struct sockaddr *)client_addr, &len);
    if(cfd == -1)
    {
        DEBUG_INFO("[ERROR] accept():%s\n", strerror(errno));
        return -1;
    }

    return cfd;
}
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