static void flood_test(char *packet, size_t length, int choose_link,
int avoid_link) {
NL_PACKET *p = (NL_PACKET *) packet;
/* REQUIRED LINK IS PROVIDED - USE IT */
if (choose_link != 0) {
if (linkinfo[choose_link].mtu < p->min_mtu)
p->min_mtu = linkinfo[choose_link].mtu;
CHECK(down_to_datalink(choose_link, packet, length));
}
/* OTHERWISE, CHOOSE THE BEST KNOWN LINKS, AVOIDING ANY SPECIFIED ONE */
else {
int links_wanted = NL_linksofminhops(p->dest);
int link;
for (link = 1; link <= nodeinfo.nlinks; ++link) {
if (link == avoid_link) /* possibly avoid this one */{
continue;
}
if (links_wanted & (1 << link)) /* use this link if wanted */
{
if (linkinfo[link].mtu < p->min_mtu)
p->min_mtu = linkinfo[link].mtu;
CHECK(down_to_datalink(link, packet, length));
}
}
}
}
// here the second parameter is the length of msg of packet!
void sendPacketPiecesToDatalink(char *packet, size_t length, int choose_link) {
//printf("send packet pieces to data link at %s\n", nodeinfo.nodename);
size_t maxPacketLength = linkinfo[choose_link].mtu - PACKET_HEADER_SIZE;
NL_PACKET *tempPacket = (NL_PACKET *) packet;
size_t tempLength = length;
char *str = tempPacket->msg;
//printf("src = %d, des = %d, linkinfo[choose_link].mtu = %d, PACKET_HEADER_SIZE = %d\n", tempPacket->src, tempPacket->dest, linkinfo[choose_link].mtu, PACKET_HEADER_SIZE);
NL_PACKET piecePacket;
piecePacket.src = tempPacket->src;
piecePacket.dest = tempPacket->dest;
piecePacket.kind = tempPacket->kind;
piecePacket.seqno = tempPacket->seqno;
piecePacket.hopcount = tempPacket->hopcount;
piecePacket.pieceNumber = tempPacket->pieceNumber;
piecePacket.pieceEnd = tempPacket->pieceEnd;
piecePacket.src_packet_length = tempPacket->src_packet_length;
piecePacket.checksum = tempPacket->checksum;
piecePacket.trans_time = tempPacket->trans_time;
piecePacket.is_resent = tempPacket->is_resent;
while (tempLength > maxPacketLength) {
//printf("packet remains %d bytes\n", tempLength);
piecePacket.length = maxPacketLength;
memcpy(piecePacket.msg, str, maxPacketLength);
CHECK(down_to_datalink(choose_link, (char *) &piecePacket,
PACKET_SIZE(piecePacket)));
//("piece %d down_to_datalink\n", piecePacket.pieceNumber);
str = str + maxPacketLength;
piecePacket.pieceNumber = piecePacket.pieceNumber + 1;
tempLength = tempLength - maxPacketLength;
}
piecePacket.pieceEnd = 1;
piecePacket.length = tempLength;
//printf("last piece contains %d bytes, pieceNumber = %d\n\n", tempLength ,piecePacket.pieceNumber);
memcpy(piecePacket.msg, str, tempLength);
////("Required link is provided link = %d\n", choose_link);
CHECK(down_to_datalink(choose_link, (char *) &piecePacket,
PACKET_SIZE(piecePacket)));
//("last piece %d down_to_datalink\n", piecePacket.pieceNumber);
////("Provided link = %d sent! \n", choose_link);
}
static void selective_flood(char *packet, int length, int links_wanted)
{
int link;
for(link=1 ; link<=nodeinfo.nlinks ; ++link)
if( links_wanted & (1<<link) )
CHECK(down_to_datalink(link, packet, length));
}
// here the second parameter is the length of msg of packet!
void sendPacketPiecesToDatalink(char *packet, size_t length, int choose_link) {
size_t maxPacketLength = linkinfo[choose_link].mtu - PACKET_HEADER_SIZE;
NL_PACKET *tempPacket = (NL_PACKET *) packet;
size_t tempLength = length;
char *str = tempPacket->msg;
NL_PACKET piecePacket;
piecePacket.src = tempPacket->src;
piecePacket.dest = tempPacket->dest;
piecePacket.kind = tempPacket->kind;
piecePacket.seqno = tempPacket->seqno;
//piecePacket.hopcount = tempPacket->hopcount;
piecePacket.trans_time = tempPacket->trans_time;
piecePacket.traveled_hops_count = tempPacket->traveled_hops_count;
memcpy(piecePacket.traveled_hops,tempPacket->traveled_hops, MAXHOPS);
piecePacket.pieceEnd = tempPacket->pieceEnd;
piecePacket.pieceNumber = tempPacket->pieceNumber;
piecePacket.checksum = tempPacket->checksum;
while (tempLength > maxPacketLength) {
piecePacket.length = maxPacketLength;
memcpy(piecePacket.msg, str, maxPacketLength);
CHECK(down_to_datalink(choose_link, (char *) &piecePacket,
PACKET_SIZE(piecePacket)));
str = str + maxPacketLength;
piecePacket.pieceNumber = piecePacket.pieceNumber + 1;
tempLength = tempLength - maxPacketLength;
}
piecePacket.pieceEnd = 1;
piecePacket.length = tempLength;
memcpy(piecePacket.msg, str, tempLength);
CHECK(down_to_datalink(choose_link, (char *) &piecePacket,
PACKET_SIZE(piecePacket)));
}