int
arp_request(u32bits dst)
{
unsigned waiting;
#ifdef ARPDEBUG
PPRINT(("Start arp_request(0x%x)\n", dst));
#endif
arp_waiting = dst;
(void)arp_output();
settimeout(ARP_RETRANSMIT);
waiting = ARP_RETRANSMIT;
while (arp_waiting != 0 && waiting <= 60000) {
if (isatimeout()) {
#ifdef ARPDEBUG
PPRINT(("ARP request sent\n"));
#endif
arp_output();
settimeout(ARP_RETRANSMIT);
waiting += ARP_RETRANSMIT;
}
if (is_intr_char())
return (NETBOOT_ABORT);
(*dlink.dl_input)(arp_buffer, sizeof(arp_buffer));
}
return (arp_waiting == 0 ? NETBOOT_SUCCESS : NETBOOT_ERROR);
}
/* ----------------------------------------------------------------------
* ip_output()
* 功能：由IP模块发送一个数据包
* 参数：
* 返回值：无
* 说明：无
* --------------------------------------------------------------------- */
void ip_output( pbuf_t * pbuf, ip_addr_t dest, uint16 len, uint8 pro, uint8 ttl )
{
uint8 i;
ip_hdr_t * hdr;
if( pbuf == ( pbuf_t * )0 )
return;
/* 填充头部 */
pbuf->app_data -= sizeof( ip_hdr_t );
hdr = (ip_hdr_t *)( pbuf->app_data );
hdr->hlen = sizeof( ip_hdr_t ) / 4;
hdr->version = IPV4;
hdr->tos = 0;
hdr->to_len = htons( len + sizeof( ip_hdr_t ) );
hdr->id = htons( seq++ );
hdr->flag = 0;
hdr->offset = 0;
hdr->ttl = ttl;
hdr->protocol = pro;
hdr->chksum = 0;
hdr->src_ip = htonl( local_ip );
hdr->dest_ip = htonl( dest );
hdr->chksum = chksum( (uint16 *)hdr, sizeof( ip_hdr_t ) );
/* 直接由网络接口发出或发至网关 */
if( (dest & net_mask) == (local_ip & net_mask) )
arp_output( pbuf, dest );
else
arp_output( pbuf, gate_way );
}
