diff options
Diffstat (limited to 'link/link-protocol.c')
| -rw-r--r-- | link/link-protocol.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/link/link-protocol.c b/link/link-protocol.c index 92cd149..3cb8e07 100644 --- a/link/link-protocol.c +++ b/link/link-protocol.c @@ -241,7 +241,7 @@ struct PureLinkSender { /* The datagram's size now; a probe of the largest flies; when the next * may go, and how many were lost (RFC 8899). */ uint32_t datagram; - bool reaching; + bool reaching, filled; /* filled: a packet was full with more to go (a larger one would carry more) */ uint64_t reach_at; unsigned reach_lost; uint64_t received; /* parts received and not yet stored */ @@ -666,20 +666,24 @@ void pure_link_sender_take(PureLinkSender *l, const unsigned char *packet, size_ } } -/* A packet of what is not sent yet, in order, within the receiver's credit: - * its body's size, or 0 when there is none. */ -static size_t fill(PureLinkSender *l, unsigned char *body, Flight *f, bool pad) { +/* A packet of what is not sent yet, in order, within the receiver's credit + * (or a probe's, which goes all the same): its body's size, or 0 when there + * is none. */ +static size_t fill(PureLinkSender *l, unsigned char *body, Flight *f, bool pad, bool probe) { size_t at = 0, most = l->datagram - HEADER - PURE_AEAD_TAG; body[at++] = F_STREAM; at += put_names(body + at, l->source, l->input); put32(body + at, l->shape); at += 4; - bool responded = l->responding; - for (unsigned k = 0; k < l->responding; ++k, at += 9) { /* the receiver's challenges, said back */ + /* The receiver's challenges, said back in the next packet that goes, + * never in one of their own: that would be a packet more for each + * address checked. Until then the answers there are at most three + * times what came from it, and the answers to a packet are less; when + * they are held back, a probe or a record sent again says it back. */ + for (unsigned k = 0; k < l->responding; ++k, at += 9) { /* let go once the packet goes */ body[at] = F_RESPONSE; put64(body + at + 1, l->respond[k]); } - l->responding = 0; /* The credit counts from the oldest record not stored: after a restart * the sender does not know yet how far the receiver stored. */ uint64_t base = l->count ? record_at(l, 0)->seq - 1 : l->stored; @@ -741,6 +745,7 @@ static size_t fill(PureLinkSender *l, unsigned char *body, Flight *f, bool pad) if (before && !full) l->unsent_from = r->seq + 1; before = before && !full; if (full) { /* the packet is full: whole, so it can go in a burst */ + l->filled = true; if (pad && f->count) { memset(body + at, F_PADDING, most - at); at = most; @@ -748,7 +753,9 @@ static size_t fill(PureLinkSender *l, unsigned char *body, Flight *f, bool pad) break; } } - return f->count || responded ? at : 0; + if (!f->count && !(probe && l->responding)) return 0; + l->responding = 0; + return at; } /* Its number is spent all the same. */ @@ -813,7 +820,7 @@ size_t pure_link_sender_packet(PureLinkSender *l, unsigned char out[PURE_LINK_DA if (!probe && !paced(l, now)) return 0; unsigned char body[BODY_MOST]; Flight f = {.pn = l->next_pn, .eliciting = true}; - if (l->datagram < DATAGRAM_MOST && !l->reaching && l->sampled && now >= l->reach_at && + if (l->datagram < DATAGRAM_MOST && l->filled && !l->reaching && l->sampled && now >= l->reach_at && l->in_flight + DATAGRAM_MOST <= l->window) { /* the path may carry more: a PING of the most, padded */ body[0] = F_PING; memset(body + 1, F_PADDING, BODY_MOST - 1); @@ -824,7 +831,7 @@ size_t pure_link_sender_packet(PureLinkSender *l, unsigned char out[PURE_LINK_DA *number = f.pn; return total; } - size_t size = fill(l, body, &f, whole); + size_t size = fill(l, body, &f, whole, probe); if (!size) { l->unused = true; if (!probe) return 0; |