void Connection::send(const void *data, size_t datalen)
{
if (mFd < 0)
{
ErrorPrint("[send] send error! socket uninited or shuted!");
return;
}
if (mConnStatus != ConnStatus_Connected)
{
ErrorPrint("[send] can't send data in such status(%d)", mConnStatus);
return;
}
const char *ptr = (const char *)data;
if (tryFlushRemainPacket())
{
int sentlen = ::send(mFd, data, datalen, 0);
// int sentlen = -1; errno = EAGAIN;
if ((size_t)sentlen == datalen)
return;
if (sentlen > 0)
{
ptr += sentlen;
datalen -= sentlen;
}
}
if (checkSocketErrors())
return;
cachePacket(ptr, datalen);
tryRegWriteEvent(); // 注册发送缓冲区可写事件
}
/*-----------------------------------------------------------------------------
* Method: void handleForward
*
* determines what interface to send a packet out of
*---------------------------------------------------------------------------*/
void handleForward(
struct sr_instance* sr,
uint8_t* packet,
unsigned int len,
char* interface )
{
struct ip* ipHdr = (struct ip*)(packet+14);
struct sr_rt* rtptr = sr->routing_table;
int cachedEntry;
/* loop through rtable for the next hop with the packet's destination ip */
while (rtptr) {
if (rtptr->dest.s_addr == ipHdr->ip_dst.s_addr)
break;
else
rtptr = rtptr->next;
}
/* if not in our rtable, send it out eth0 to the intarwebz */
if (!rtptr) {
rtptr = sr->routing_table; // eth0
if ((cachedEntry = arpSearchCache(rtptr->gw.s_addr)) > -1) {
forwardPacket(sr, packet, len, rtptr->interface, arpReturnEntryMac(cachedEntry));
} else {
cachePacket(sr, packet, len, rtptr);
}
}
/* look through arp cache for mac matching the ip destination. if we have it,
* forward our packet. otherwise, cache the packet and wait for an arp reply
* to tell us the correct mac address */
if ((cachedEntry = arpSearchCache(rtptr->gw.s_addr)) > -1) {
forwardPacket(sr, packet, len, rtptr->interface, arpReturnEntryMac(cachedEntry));
} else {
cachePacket(sr, packet, len, rtptr);
}
}
