Before we allowed buf->offset to be equal to buf->size. This caused an
issue where buffer_call() would call the callback twice, once for 0
bytes at the end of the buffer, and once for len bytes at the start of
the buffer. This would cause the callback function to think the channel
had encountered an error.
If the data in the ringbuffer wraps around, and we call the receive
callback for the first part of the data, the callback function might
close the channel, so we must not call the callback for the second part
of the data.
uint32_t realoffset = buf->offset + offset;
uint32_t realoffset = buf->offset + offset;
- if(buf->size - buf->offset < offset) {
+ if(buf->size - buf->offset <= offset) {
// The offset wrapped
realoffset -= buf->size;
}
// The offset wrapped
realoffset -= buf->size;
}
uint32_t realoffset = buf->offset + offset;
uint32_t realoffset = buf->offset + offset;
- if(buf->size - buf->offset < offset) {
+ if(buf->size - buf->offset <= offset) {
// The offset wrapped
realoffset -= buf->size;
}
// The offset wrapped
realoffset -= buf->size;
}
}
// Copy data from the buffer without removing it.
}
// 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;
// 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;
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
// 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;
}
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;
if(rx2 < 0) {
return rx2;
return rx1 + rx2;
}
} else {
return rx1 + rx2;
}
} else {
- return cb(arg, buf->data + realoffset, len);
+ return c->recv(c, buf->data + realoffset, len);
- if(buf->size - buf->offset < len) {
+ if(buf->size - buf->offset <= len) {
buf->offset -= buf->size;
}
buf->offset -= buf->size;
}
len = c->sacks[0].offset + c->sacks[0].len;
size_t remainder = len - offset;
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
}
// 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;
}
c->rcv.nxt = hdr->seq + len;