tcp_buf.c

一个基于linux的TCP/IP协议栈的实现

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include "my_inet.h"
#include <arpa/inet.h>

int main(void)
{
	int fd, n, r;
	struct sockaddr_in srv, client;
	
	srv.sin_family = MY_AF_INET;
	srv.sin_port = htons(5002);
	inet_aton("172.16.48.1", &srv.sin_addr);

	client.sin_family = MY_AF_INET;
	client.sin_port = htons(10000);
	client.sin_addr.s_addr = inet_addr("172.16.48.13");

	if( (fd = socket( MY_AF_INET, SOCK_STREAM, MY_IPPROTO_TCP) ) < 0 ){
		perror("socket");
		return -1;
	}
	if( bind(fd, (struct sockaddr *)&client, sizeof(client) ) < 0 ){
		perror("bind: ");
		return -1;
	}

	if( connect(fd, (struct sockaddr *)&srv, sizeof(srv)) < 0 ){
		perror("connect: ");
		return -1;
	}
	
	int rcvbuf_len = 10000 * 1024;
	int len = sizeof(rcvbuf_len);
	if( setsockopt( fd, SOL_SOCKET, SO_SNDBUF, (void *)&rcvbuf_len, len ) < 0 ){
		perror("setsockopt: ");
		return -1;
	}
	if( getsockopt( fd, SOL_SOCKET, SO_SNDBUF, (void *)&rcvbuf_len, &len ) < 0 ){
        perror("getsockopt: ");
        return -1;
    }	
	printf("the recevice buf len: %d\n", rcvbuf_len );
	printf("send msg!\n");
	char send_buf[4096];
	strcpy( send_buf, "my first tcp packet!\n" );
	//memset(send_buf, 'a', 4095);
	//send_buf[4095] = '\0';
	if( send(fd, send_buf, strlen(send_buf), 0 ) < 0 ){
		perror("send: ");
		return -1;
	}

	if( recv( fd, send_buf, sizeof(send_buf), 0 ) < 0 ){
		perror("recv: ");
		return -1;
	}
	printf("recv from: %s\n", send_buf );
	close(fd);
/*	
	n = sizeof(cli);
	while(1){
		if( (r = recv(fd, buf, MAXBUF, 0)) < 0 ){
			perror("recv:");
		}else{
			buf[r] = 0;
			fprintf(stdout, "Mensaje desde: %s", buf);
		}
	}
*/
}