test.c.3

实现一个网卡到内存空间的零拷贝程序

/* Testje */

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "rawtx.h"

#define ETHER_ADDR_FORMAT "%02X:%02X:%02X:%02X:%02X:%02X"
#define ETHER_ADDR_DATA(a) (a)[0], (a)[1], (a)[2], (a)[3], (a)[4], (a)[5]

#define TO_PORT		5800
#define FROM_PORT	5000
#define TO_IP		"192.16.199.38"
#define FROM_IP		"192.16.199.42"
#define FROM_ETHER	{ 0x00, 0x01, 0x02, 0x08, 0xA6, 0xF2 }
#define TO_ETHER	{ 0x00, 0x50, 0x04, 0x63, 0xDB, 0xEF }
#define NET_DEVICE	"eth0"

#define DATA_LEN	1400
#define COUNT		10000

#define RAWTX_DEVICE "/user/jorisvr/jstage/rawtx_device"

static int rawtx_fd;
static unsigned char * dbuffer;

void init_rawtx(void)
{
	unsigned char sether[6] = FROM_ETHER, dether[6] = TO_ETHER;
	struct sockaddr_in addr;

	printf("Opening rawtx device...\n");
	rawtx_fd = open(RAWTX_DEVICE, O_RDWR);
	if (rawtx_fd < 0) {
		perror("open");
		exit(1);
	}

	printf("Mapping buffer pool...\n");
	dbuffer = mmap(NULL, RAWTX_BUFPOOL_SIZE, PROT_READ|PROT_WRITE,
	               MAP_SHARED, rawtx_fd, 0);
	if (dbuffer == MAP_FAILED) {
		perror("mmap");
		exit(1);
	}

	printf("Setting device %s...\n", NET_DEVICE);
	if (ioctl(rawtx_fd, RAWTX_IOCTL_SETDEVICE, NET_DEVICE) < 0) {
		perror("ioctl setdevice");
		exit(1);
	}

	printf("Setting protocol to UDP/IP...\n");
	if (ioctl(rawtx_fd, RAWTX_IOCTL_SETPROTO, RAWTX_PROTO_UDPIP) < 0) {
		perror("ioctl setproto");
		exit(1);
	}

	printf("Setting destination address " ETHER_ADDR_FORMAT "...\n",
	       ETHER_ADDR_DATA(dether));
	if (ioctl(rawtx_fd, RAWTX_IOCTL_SETDADDR, &dether) < 0) {
		perror("ioctl setdaddr");
		exit(1);
	}

	printf("Setting source address %s:%d...\n", FROM_IP, FROM_PORT);
	addr.sin_family = AF_INET;
	addr.sin_port = htons(FROM_PORT);
	inet_aton(FROM_IP, &addr.sin_addr);
	if (ioctl(rawtx_fd, RAWTX_IOCTL_SETSRCADDR, &addr) < 0) {
		perror("ioctl setsrcaddr");
		exit(1);
	}

	printf("Setting destination address %s:%d...\n", TO_IP, TO_PORT);
	addr.sin_family = AF_INET;
	addr.sin_port = htons(TO_PORT);
	inet_aton(TO_IP, &addr.sin_addr);
	if (ioctl(rawtx_fd, RAWTX_IOCTL_SETDSTADDR, &addr) < 0) {
		perror("ioctl setdstaddr");
		exit(1);
	}
}

void send_packet(unsigned long bufofs)
{
	int err;
	if ((err = ioctl(rawtx_fd, RAWTX_IOCTL_SENDBUFFER, bufofs)) != 0) {
		if (err > 0)
			printf("Packet drop!!\n");
		else {
			perror("ioctl sendbuffer");
			exit(1);
		}
	}
}


static void get_buffer(unsigned long *ofs, struct rawtx_buffer **buf,
                       unsigned char **data_buf)
{
	if (ioctl(rawtx_fd, RAWTX_IOCTL_GETBUFFER, ofs)) {
		perror("ioctl getbuffer");
		exit(1);
	}

	*buf = (struct rawtx_buffer *) (dbuffer + *ofs);
	*data_buf = dbuffer + (*buf)->data_ofs;
}


int main(void)
{
	unsigned long bufofs;
	struct rawtx_buffer *buf;
	unsigned char *data_buf;
	int i;

	init_rawtx();

	printf("Sending packets...\n");

	/* Tell ttcp to start the timer. */
	get_buffer(&bufofs, &buf, &data_buf);
	buf->data_len = 4;
	send_packet(bufofs);

	for (i = 0; i < COUNT; i++) {
		get_buffer(&bufofs, &buf, &data_buf);
		*(unsigned int *)(data_buf) = i;
		strcpy(data_buf + 8, "...Hallo allemaal hier");
		buf->data_len = DATA_LEN;
		send_packet(bufofs);
	}

	/* Tell ttcp that we're done. */
	get_buffer(&bufofs, &buf, &data_buf);
	buf->data_len = 4;
	send_packet(bufofs);

	get_buffer(&bufofs, &buf, &data_buf);
	buf->data_len = 4;
	send_packet(bufofs);

	get_buffer(&bufofs, &buf, &data_buf);
	buf->data_len = 4;
	send_packet(bufofs);

	get_buffer(&bufofs, &buf, &data_buf);
	buf->data_len = 4;
	send_packet(bufofs);

	close(rawtx_fd);

	return 0;
}