uint32_t realoffset = buf->offset + offset;
- if(buf->size - buf->offset < offset) {
+ if(buf->size - buf->offset <= offset) {
// The offset wrapped
realoffset -= buf->size;
}
uint32_t realoffset = buf->offset + offset;
- if(buf->size - buf->offset < offset) {
+ if(buf->size - buf->offset <= offset) {
// The offset wrapped
realoffset -= buf->size;
}
}
// Copy data from the buffer without removing it.
-static ssize_t buffer_call(struct buffer *buf, utcp_recv_t cb, void *arg, size_t offset, size_t len) {
+static ssize_t buffer_call(struct utcp_connection *c, struct buffer *buf, size_t offset, size_t len) {
+ if(!c->recv) {
+ return len;
+ }
+
// Ensure we don't copy more than is actually stored in the buffer
if(offset >= buf->used) {
return 0;
uint32_t realoffset = buf->offset + offset;
- if(buf->size - buf->offset < offset) {
+ if(buf->size - buf->offset <= offset) {
// The offset wrapped
realoffset -= buf->size;
}
if(buf->size - realoffset < len) {
// The data is wrapped
- ssize_t rx1 = cb(arg, buf->data + realoffset, buf->size - realoffset);
+ ssize_t rx1 = c->recv(c, buf->data + realoffset, buf->size - realoffset);
if(rx1 < buf->size - realoffset) {
return rx1;
}
- ssize_t rx2 = cb(arg, buf->data, len - (buf->size - realoffset));
+ // The channel might have been closed by the previous callback
+ if(!c->recv) {
+ return len;
+ }
+
+ ssize_t rx2 = c->recv(c, buf->data, len - (buf->size - realoffset));
if(rx2 < 0) {
return rx2;
return rx1 + rx2;
}
} else {
- return cb(arg, buf->data + realoffset, len);
+ return c->recv(c, buf->data + realoffset, len);
}
}
len = buf->used;
}
- if(buf->size - buf->offset < len) {
+ if(buf->size - buf->offset <= len) {
buf->offset -= buf->size;
}
struct utcp *utcp = c->utcp;
- if (utcp->retransmit) {
+ if(utcp->retransmit) {
utcp->retransmit(c);
}
len = c->sacks[0].offset + c->sacks[0].len;
size_t remainder = len - offset;
- if(c->recv) {
- ssize_t rxd = buffer_call(&c->rcvbuf, c->recv, c, offset, remainder);
+ ssize_t rxd = buffer_call(c, &c->rcvbuf, offset, remainder);
- if(rxd != (ssize_t)remainder) {
- // TODO: handle the application not accepting all data.
- abort();
- }
+ if(rxd != (ssize_t)remainder) {
+ // TODO: handle the application not accepting all data.
+ abort();
}
}
}
}
// Send the packet if it's the final fragment
- if(!(hdr->ctl & MF) && c->recv) {
- buffer_call(&c->rcvbuf, c->recv, c, 0, hdr->wnd + len);
+ if(!(hdr->ctl & MF)) {
+ buffer_call(c, &c->rcvbuf, 0, hdr->wnd + len);
}
c->rcv.nxt = hdr->seq + len;
print_packet(c, "send", &pkt, sizeof(hdr));
utcp->send(utcp, &pkt, sizeof(hdr));
}
+
+ start_retransmit_timer(c);
} else {
// No, we don't want your packets, send a RST back
len = 1;
}
c->rcv.irs = hdr.seq;
- c->rcv.nxt = hdr.seq;
+ c->rcv.nxt = hdr.seq + 1;
if(c->shut_wr) {
c->snd.last++;
set_state(c, ESTABLISHED);
}
- // TODO: notify application of this somehow.
break;
case SYN_RECEIVED:
case CLOSING:
case LAST_ACK:
case TIME_WAIT:
- // Ehm, no. We should never receive a second SYN.
- return 0;
+ // This could be a retransmission. Ignore the SYN flag, but send an ACK back.
+ break;
default:
#ifdef UTCP_DEBUG
#endif
return 0;
}
-
- // SYN counts as one sequence number
- c->rcv.nxt++;
}
// 6. Process new data
return NULL;
}
+ utcp_set_mtu(utcp, DEFAULT_MTU);
+
+ if(!utcp->pkt) {
+ free(utcp);
+ return NULL;
+ }
+
if(!CLOCK_GRANULARITY) {
struct timespec res;
clock_getres(UTCP_CLOCK, &res);
utcp->pre_accept = pre_accept;
utcp->send = send;
utcp->priv = priv;
- utcp_set_mtu(utcp, DEFAULT_MTU);
utcp->timeout = DEFAULT_USER_TIMEOUT; // sec
return utcp;