static uint16_t _send_1st_fragment(gnrc_netif_t *iface, gnrc_pktsnip_t *pkt,
size_t payload_len, size_t datagram_size)
{
gnrc_pktsnip_t *frag;
uint16_t local_offset = 0;
/* payload_len: actual size of the packet vs
* datagram_size: size of the uncompressed IPv6 packet */
int payload_diff = (datagram_size - payload_len);
/* virtually add payload_diff to flooring to account for offset (must be divisable by 8)
* in uncompressed datagram */
uint16_t max_frag_size = _floor8(iface->sixlo.max_frag_size + payload_diff -
sizeof(sixlowpan_frag_t)) - payload_diff;
sixlowpan_frag_t *hdr;
uint8_t *data;
DEBUG("6lo frag: determined max_frag_size = %" PRIu16 "\n", max_frag_size);
frag = _build_frag_pkt(pkt, payload_len,
max_frag_size + sizeof(sixlowpan_frag_t));
if (frag == NULL) {
return 0;
}
hdr = frag->next->data;
data = (uint8_t *)(hdr + 1);
hdr->disp_size = byteorder_htons((uint16_t)datagram_size);
hdr->disp_size.u8[0] |= SIXLOWPAN_FRAG_1_DISP;
hdr->tag = byteorder_htons(_tag);
/* Tell the link layer that we will send more fragments */
gnrc_netif_hdr_t *netif_hdr = frag->data;
netif_hdr->flags |= GNRC_NETIF_HDR_FLAGS_MORE_DATA;
pkt = pkt->next; /* don't copy netif header */
while (pkt != NULL) {
size_t clen = _min(max_frag_size - local_offset, pkt->size);
memcpy(data + local_offset, pkt->data, clen);
local_offset += clen;
if (local_offset >= max_frag_size) {
break;
}
pkt = pkt->next;
}
DEBUG("6lo frag: send first fragment (datagram size: %u, "
"datagram tag: %" PRIu16 ", fragment size: %" PRIu16 ")\n",
(unsigned int)datagram_size, _tag, local_offset);
gnrc_sixlowpan_dispatch_send(frag, NULL, 0);
return local_offset;
}
static uint16_t _send_1st_fragment(ng_sixlowpan_netif_t *iface, ng_pktsnip_t *pkt,
size_t payload_len, size_t datagram_size)
{
ng_pktsnip_t *frag;
uint16_t max_frag_size = _floor8(iface->max_frag_size -
(payload_len - datagram_size) -
sizeof(ng_sixlowpan_frag_t));
uint16_t local_offset = 0;
ng_sixlowpan_frag_t *hdr;
uint8_t *data;
DEBUG("6lo frag: determined max_frag_size = %" PRIu16 "\n", max_frag_size);
/* 6LoWPAN dispatches don't count into that */
max_frag_size += (payload_len - datagram_size);
frag = _build_frag_pkt(pkt, payload_len,
max_frag_size + sizeof(ng_sixlowpan_frag_t));
if (frag == NULL) {
return 0;
}
hdr = frag->next->data;
data = (uint8_t *)(hdr + 1);
hdr->disp_size = byteorder_htons((uint16_t)datagram_size);
hdr->disp_size.u8[0] |= NG_SIXLOWPAN_FRAG_1_DISP;
hdr->tag = byteorder_htons(_tag);
pkt = pkt->next; /* don't copy netif header */
while (pkt != NULL) {
size_t clen = _min(max_frag_size - local_offset, pkt->size);
memcpy(data + local_offset, pkt->data, clen);
local_offset += clen;
if (local_offset >= max_frag_size) {
break;
}
pkt = pkt->next;
}
DEBUG("6lo frag: send first fragment (datagram size: %u, "
"datagram tag: %" PRIu16 ", fragment size: %" PRIu16 ")\n",
(unsigned int)datagram_size, _tag, local_offset);
ng_netapi_send(iface->pid, frag);
return local_offset;
}
static uint16_t _send_nth_fragment(gnrc_netif_t *iface, gnrc_pktsnip_t *pkt,
size_t payload_len, size_t datagram_size,
uint16_t offset)
{
gnrc_pktsnip_t *frag;
/* since dispatches aren't supposed to go into subsequent fragments, we need not account
* for payload difference as for the first fragment */
uint16_t max_frag_size = _floor8(iface->sixlo.max_frag_size - sizeof(sixlowpan_frag_n_t));
uint16_t local_offset = 0, offset_count = 0;
sixlowpan_frag_n_t *hdr;
uint8_t *data;
DEBUG("6lo frag: determined max_frag_size = %" PRIu16 "\n", max_frag_size);
frag = _build_frag_pkt(pkt,
payload_len - offset + sizeof(sixlowpan_frag_n_t),
max_frag_size + sizeof(sixlowpan_frag_n_t));
if (frag == NULL) {
return 0;
}
hdr = frag->next->data;
data = (uint8_t *)(hdr + 1);
/* XXX: truncation of datagram_size > 4095 may happen here */
hdr->disp_size = byteorder_htons((uint16_t)datagram_size);
hdr->disp_size.u8[0] |= SIXLOWPAN_FRAG_N_DISP;
hdr->tag = byteorder_htons(_tag);
/* don't mention payload diff in offset */
hdr->offset = (uint8_t)((offset + (datagram_size - payload_len)) >> 3);
pkt = pkt->next; /* don't copy netif header */
while ((pkt != NULL) && (offset_count != offset)) { /* go to offset */
offset_count += (uint16_t)pkt->size;
if (offset_count > offset) { /* we overshot */
/* => copy rest of partly send packet snip */
uint16_t pkt_offset = offset - (offset_count - ((uint16_t)pkt->size));
size_t clen = _min(max_frag_size, pkt->size - pkt_offset);
memcpy(data, ((uint8_t *)pkt->data) + pkt_offset, clen);
local_offset = clen;
if (local_offset == max_frag_size) {
if ((clen < (pkt->size - pkt_offset)) || (pkt->next != NULL)) {
/* Tell the link layer that we will send more fragments */
gnrc_netif_hdr_t *netif_hdr = frag->data;
netif_hdr->flags |= GNRC_NETIF_HDR_FLAGS_MORE_DATA;
}
}
pkt = pkt->next;
break;
}
pkt = pkt->next;
}
if (local_offset < max_frag_size) { /* copy other packet snips */
while (pkt != NULL) {
size_t clen = _min(max_frag_size - local_offset, pkt->size);
memcpy(data + local_offset, pkt->data, clen);
local_offset += clen;
if (local_offset == max_frag_size) {
if ((clen < pkt->size) || (pkt->next != NULL)) {
/* Tell the link layer that we will send more fragments */
gnrc_netif_hdr_t *netif_hdr = frag->data;
netif_hdr->flags |= GNRC_NETIF_HDR_FLAGS_MORE_DATA;
}
break;
}
pkt = pkt->next;
}
}
DEBUG("6lo frag: send subsequent fragment (datagram size: %u, "
"datagram tag: %" PRIu16 ", offset: %" PRIu8 " (%u bytes), "
"fragment size: %" PRIu16 ")\n",
(unsigned int)datagram_size, _tag, hdr->offset, hdr->offset << 3,
local_offset);
gnrc_sixlowpan_dispatch_send(frag, NULL, 0);
return local_offset;
}
static uint16_t _send_nth_fragment(ng_sixlowpan_netif_t *iface, ng_pktsnip_t *pkt,
size_t payload_len, size_t datagram_size,
uint16_t offset)
{
ng_pktsnip_t *frag;
uint16_t max_frag_size = _floor8(iface->max_frag_size - sizeof(ng_sixlowpan_frag_n_t));
uint16_t local_offset = 0, offset_count = 0;
ng_sixlowpan_frag_n_t *hdr;
uint8_t *data;
DEBUG("6lo frag: determined max_frag_size = %" PRIu16 "\n", max_frag_size);
frag = _build_frag_pkt(pkt,
payload_len - offset + sizeof(ng_sixlowpan_frag_n_t),
max_frag_size + sizeof(ng_sixlowpan_frag_n_t));
if (frag == NULL) {
return 0;
}
hdr = frag->next->data;
data = (uint8_t *)(hdr + 1);
/* XXX: truncation of datagram_size > 4095 may happen here */
hdr->disp_size = byteorder_htons((uint16_t)datagram_size);
hdr->disp_size.u8[0] |= NG_SIXLOWPAN_FRAG_N_DISP;
hdr->tag = byteorder_htons(_tag);
hdr->offset = (uint8_t)(offset >> 3);
pkt = pkt->next; /* don't copy netif header */
while ((pkt != NULL) && (offset_count != offset)) { /* go to offset */
offset_count += (uint16_t)pkt->size;
if (offset_count > offset) { /* we overshot */
/* => copy rest of partly send packet snip */
uint16_t pkt_offset = offset - (offset_count - ((uint16_t)pkt->size));
size_t clen = _min(max_frag_size, pkt->size - pkt_offset);
memcpy(data, ((uint8_t *)pkt->data) + pkt_offset, clen);
local_offset = clen;
pkt = pkt->next;
break;
}
pkt = pkt->next;
}
if (local_offset < max_frag_size) { /* copy other packet snips */
while (pkt != NULL) {
size_t clen = _min(max_frag_size - local_offset, pkt->size);
memcpy(data + local_offset, pkt->data, clen);
local_offset += clen;
if (local_offset == max_frag_size) {
break;
}
pkt = pkt->next;
}
}
DEBUG("6lo frag: send subsequent fragment (datagram size: %u, "
"datagram tag: %" PRIu16 ", offset: %" PRIu8 " (%u bytes), "
"fragment size: %" PRIu16 ")\n",
(unsigned int)datagram_size, _tag, hdr->offset, hdr->offset << 3,
local_offset);
ng_netapi_send(iface->pid, frag);
return local_offset;
}
