1 #include "CongestionControl.hpp"
2 #include "Connection.hpp"
3 #include "ConnectionHandler.hpp"
7 #include "../app/init.hpp"
8 #include "../model/Model.hpp"
9 #include "../world/Entity.hpp"
10 #include "../world/EntityState.hpp"
19 constexpr size_t Packet::Ping::MAX_LEN;
20 constexpr size_t Packet::Login::MAX_LEN;
21 constexpr size_t Packet::Join::MAX_LEN;
22 constexpr size_t Packet::Part::MAX_LEN;
23 constexpr size_t Packet::PlayerUpdate::MAX_LEN;
24 constexpr size_t Packet::SpawnEntity::MAX_LEN;
25 constexpr size_t Packet::DespawnEntity::MAX_LEN;
26 constexpr size_t Packet::EntityUpdate::MAX_LEN;
27 constexpr size_t Packet::PlayerCorrection::MAX_LEN;
28 constexpr size_t Packet::ChunkBegin::MAX_LEN;
29 constexpr size_t Packet::ChunkData::MAX_LEN;
30 constexpr size_t Packet::BlockUpdate::MAX_LEN;
31 constexpr size_t Packet::Message::MAX_LEN;
32 constexpr size_t Packet::Message::MAX_MESSAGE_LEN;
35 CongestionControl::CongestionControl()
36 // I know, I know, it's an estimate (about 20 for IPv4, 48 for IPv6)
38 // only sample every eighth packet for measuring RTT
52 // rtt > 100ms or packet loss > 5% is BAD
55 // rtt > 250ms or packet loss > 15% is UGLY
58 , mode_keep_time(1000) {
59 Uint32 now = SDL_GetTicks();
60 for (Uint32 &s : stamps) {
69 void CongestionControl::PacketSent(uint16_t seq) noexcept {
70 if (!SamplePacket(seq)) {
73 stamp_cursor = (stamp_cursor + 1) % 16;
74 stamps[stamp_cursor] = SDL_GetTicks();
78 void CongestionControl::PacketLost(uint16_t seq) noexcept {
84 void CongestionControl::PacketReceived(uint16_t seq) noexcept {
90 void CongestionControl::UpdatePacketLoss() noexcept {
91 unsigned int packets_total = packets_lost + packets_received;
92 if (packets_total >= 256) {
93 packet_loss = float(packets_lost) / float(packets_total);
99 void CongestionControl::UpdateRTT(std::uint16_t seq) noexcept {
100 if (!SamplePacket(seq)) return;
101 int16_t diff = int16_t(seq) - int16_t(stamp_last);
103 if (diff > 0 || diff < -15) {
104 // packet outside observed time frame
107 int cur_rtt = SDL_GetTicks() - stamps[(stamp_cursor + diff + 16) % 16];
108 rtt += (cur_rtt - rtt) * 0.1f;
111 bool CongestionControl::SamplePacket(std::uint16_t seq) const noexcept {
112 return seq % sample_skip == 0;
115 void CongestionControl::PacketIn(const UDPpacket &pack) noexcept {
116 rx_bytes += pack.len + packet_overhead;
120 void CongestionControl::PacketOut(const UDPpacket &pack) noexcept {
121 tx_bytes += pack.len + packet_overhead;
125 void CongestionControl::UpdateStats() noexcept {
126 Uint32 now = SDL_GetTicks();
127 if (now < next_sample) {
131 tx_kbps = float(tx_bytes) * (1.0f / 1024.0f);
132 rx_kbps = float(rx_bytes) * (1.0f / 1024.0f);
139 void CongestionControl::UpdateMode() noexcept {
140 Mode now_mode = Conditions();
141 if (now_mode > mode) {
142 ChangeMode(now_mode);
143 } else if (now_mode < mode) {
144 CheckUpgrade(now_mode);
150 void CongestionControl::CheckUpgrade(Mode m) noexcept {
151 Uint32 now = SDL_GetTicks();
152 Uint32 time_in_mode = now - mode_entered;
153 if (time_in_mode < mode_keep_time) {
159 void CongestionControl::ChangeMode(Mode m) noexcept {
160 Uint32 now = SDL_GetTicks();
162 // changed to worse mode
163 // if we spent less than 10 seconds in better mode
164 // double keep time till up to 64 seconds
165 if (now - mode_entered < 10000) {
166 if (mode_keep_time < 64000) {
173 mode_reset = mode_entered;
176 void CongestionControl::KeepMode() noexcept {
177 mode_reset = SDL_GetTicks();
178 // if in good mode for 10 seconds, halve keep time till down to one second
179 if (mode == GOOD && mode_keep_time > 1000 && mode_step - mode_reset > 10000) {
181 mode_step = mode_reset;
185 CongestionControl::Mode CongestionControl::Conditions() const noexcept {
186 if (rtt > ugly_rtt || packet_loss > ugly_loss) {
188 } else if (rtt > bad_rtt || packet_loss > bad_loss) {
196 Connection::Connection(const IPaddress &addr)
201 , ctrl_out{ 0, 0xFFFF, 0xFFFFFFFF }
202 , ctrl_in{ 0, 0xFFFF, 0xFFFFFFFF }
208 bool Connection::Matches(const IPaddress &remote) const noexcept {
209 return memcmp(&addr, &remote, sizeof(IPaddress)) == 0;
212 void Connection::FlagSend() noexcept {
216 void Connection::FlagRecv() noexcept {
220 bool Connection::ShouldPing() const noexcept {
221 return !closed && send_timer.HitOnce();
224 bool Connection::TimedOut() const noexcept {
225 return recv_timer.HitOnce();
228 void Connection::Update(int dt) {
229 send_timer.Update(dt);
230 recv_timer.Update(dt);
234 Handler().OnTimeout();
240 uint16_t Connection::Send(UDPpacket &udp_pack, UDPsocket sock) {
241 Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
242 pack.header.ctrl = ctrl_out;
243 uint16_t seq = ctrl_out.seq++;
245 udp_pack.address = addr;
246 if (SDLNet_UDP_Send(sock, -1, &udp_pack) == 0) {
247 throw NetError("SDLNet_UDP_Send");
251 Handler().PacketOut(udp_pack);
252 Handler().PacketSent(seq);
259 void Connection::Received(const UDPpacket &udp_pack) {
260 Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
263 int16_t diff = int16_t(pack.header.ctrl.seq) - int16_t(ctrl_out.ack);
268 ctrl_out.hist <<= diff;
269 ctrl_out.hist |= 1 << (diff - 1);
271 } else if (diff < 0 && diff >= -32) {
272 ctrl_out.hist |= 1 << (-diff - 1);
274 ctrl_out.ack = pack.header.ctrl.seq;
281 Packet::TControl ctrl_new = pack.header.ctrl;
282 Handler().PacketIn(udp_pack);
283 Handler().Handle(udp_pack);
286 // if the packet holds more recent information
287 // check if remote failed to ack one of our packets
288 diff = int16_t(ctrl_new.ack) - int16_t(ctrl_in.ack);
289 // should always be true, but you never know…
291 for (int i = 0; i < diff; ++i) {
292 if (i > 32 || (i < 32 && (ctrl_in.hist & (1 << (31 - i))) == 0)) {
293 Handler().PacketLost(ctrl_in.ack - 32 + i);
297 // check for newly ack'd packets
298 for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); --s) {
299 if (ctrl_new.Acks(s) && !ctrl_in.Acks(s)) {
300 Handler().PacketReceived(s);
307 bool Packet::TControl::Acks(uint16_t s) const noexcept {
308 int16_t diff = int16_t(ack) - int16_t(s);
309 if (diff == 0) return true;
310 if (diff < 0 || diff > 32) return false;
311 return (hist & (1 << (diff - 1))) != 0;
314 uint16_t Connection::SendPing(UDPpacket &udp_pack, UDPsocket sock) {
315 Packet::Make<Packet::Ping>(udp_pack);
316 return Send(udp_pack, sock);
320 ConnectionHandler::ConnectionHandler()
325 void ConnectionHandler::PacketSent(uint16_t seq) noexcept {
329 void ConnectionHandler::PacketLost(uint16_t seq) {
334 void ConnectionHandler::PacketReceived(uint16_t seq) {
335 OnPacketReceived(seq);
336 cc.PacketReceived(seq);
339 void ConnectionHandler::PacketIn(const UDPpacket &pack) noexcept {
343 void ConnectionHandler::PacketOut(const UDPpacket &pack) noexcept {
348 ostream &operator <<(ostream &out, const IPaddress &addr) {
349 const unsigned char *host = reinterpret_cast<const unsigned char *>(&addr.host);
351 << '.' << int(host[1])
352 << '.' << int(host[2])
353 << '.' << int(host[3]);
355 out << ':' << SDLNet_Read16(&addr.port);
361 const char *Packet::Type2String(uint8_t t) noexcept {
371 case PlayerUpdate::TYPE:
372 return "PlayerUpdate";
373 case SpawnEntity::TYPE:
374 return "SpawnEntity";
375 case DespawnEntity::TYPE:
376 return "DespawnEntity";
377 case EntityUpdate::TYPE:
378 return "EntityUpdate";
379 case PlayerCorrection::TYPE:
380 return "PlayerCorrection";
381 case ChunkBegin::TYPE:
383 case ChunkData::TYPE:
385 case BlockUpdate::TYPE:
386 return "BlockUpdate";
395 void Packet::Payload::Write(const T &src, size_t off) noexcept {
396 if ((length - off) < sizeof(T)) {
397 // dismiss out of bounds write
400 *reinterpret_cast<T *>(&data[off]) = src;
404 void Packet::Payload::Read(T &dst, size_t off) const noexcept {
405 if ((length - off) < sizeof(T)) {
406 // dismiss out of bounds read
409 dst = *reinterpret_cast<T *>(&data[off]);
412 void Packet::Payload::WriteString(const string &src, size_t off, size_t maxlen) noexcept {
413 uint8_t *dst = &data[off];
414 size_t len = min(maxlen, length - off);
415 if (src.size() < len) {
416 memset(dst, '\0', len);
417 memcpy(dst, src.c_str(), src.size());
419 memcpy(dst, src.c_str(), len);
423 void Packet::Payload::ReadString(string &dst, size_t off, size_t maxlen) const noexcept {
424 size_t len = min(maxlen, length - off);
427 for (size_t i = 0; i < len && data[off + i] != '\0'; ++i) {
428 dst.push_back(data[off + i]);
432 void Packet::Payload::Write(const glm::quat &val, size_t off) noexcept {
433 WritePackN(val.w, off);
434 WritePackN(val.x, off + 2);
435 WritePackN(val.y, off + 4);
436 WritePackN(val.z, off + 6);
439 void Packet::Payload::Read(glm::quat &val, size_t off) const noexcept {
440 ReadPackN(val.w, off);
441 ReadPackN(val.x, off + 2);
442 ReadPackN(val.y, off + 4);
443 ReadPackN(val.z, off + 6);
444 val = normalize(val);
447 void Packet::Payload::Write(const EntityState &state, size_t off) noexcept {
448 Write(state.chunk_pos, off);
449 WritePackU(state.block_pos * (1.0f / 16.0f), off + 12);
450 Write(state.velocity, off + 18);
451 Write(state.orient, off + 30);
452 WritePackN(state.pitch * PI_0p5_inv, off + 38);
453 WritePackN(state.yaw * PI_inv, off + 40);
456 void Packet::Payload::Read(EntityState &state, size_t off) const noexcept {
457 Read(state.chunk_pos, off);
458 ReadPackU(state.block_pos, off + 12);
459 Read(state.velocity, off + 18);
460 Read(state.orient, off + 30);
461 ReadPackN(state.pitch, off + 38);
462 ReadPackN(state.yaw, off + 40);
463 state.block_pos *= 16.0f;
464 state.pitch *= PI_0p5;
468 void Packet::Payload::Write(const EntityState &state, const glm::ivec3 &base, size_t off) noexcept {
469 WritePackB(state.chunk_pos - base, off);
470 WritePackU(state.block_pos * (1.0f / 16.0f), off + 3);
471 Write(state.velocity, off + 9);
472 Write(state.orient, off + 21);
473 WritePackN(state.pitch * PI_0p5_inv, off + 29);
474 WritePackN(state.yaw * PI_inv, off + 31);
477 void Packet::Payload::Read(EntityState &state, const glm::ivec3 &base, size_t off) const noexcept {
478 ReadPackB(state.chunk_pos, off);
479 ReadPackU(state.block_pos, off + 3);
480 Read(state.velocity, off + 9);
481 Read(state.orient, off + 21);
482 ReadPackN(state.pitch, off + 29);
483 ReadPackN(state.yaw, off + 31);
484 state.chunk_pos += base;
485 state.block_pos *= 16.0f;
486 state.pitch *= PI_0p5;
490 void Packet::Payload::WritePackB(const glm::ivec3 &val, size_t off) noexcept {
491 Write(int8_t(val.x), off);
492 Write(int8_t(val.y), off + 1);
493 Write(int8_t(val.z), off + 2);
496 void Packet::Payload::ReadPackB(glm::ivec3 &val, size_t off) const noexcept {
506 void Packet::Payload::WritePackN(float val, size_t off) noexcept {
507 int16_t raw = glm::clamp(glm::round(val * 32767.0f), -32767.0f, 32767.0f);
511 void Packet::Payload::ReadPackN(float &val, size_t off) const noexcept {
514 val = raw * (1.0f/32767.0f);
517 void Packet::Payload::WritePackN(const glm::vec3 &val, size_t off) noexcept {
518 WritePackN(val.x, off);
519 WritePackN(val.y, off + 2);
520 WritePackN(val.z, off + 4);
523 void Packet::Payload::ReadPackN(glm::vec3 &val, size_t off) const noexcept {
524 ReadPackN(val.x, off);
525 ReadPackN(val.y, off + 2);
526 ReadPackN(val.z, off + 4);
529 void Packet::Payload::WritePackU(float val, size_t off) noexcept {
530 uint16_t raw = glm::clamp(glm::round(val * 65535.0f), 0.0f, 65535.0f);
534 void Packet::Payload::ReadPackU(float &val, size_t off) const noexcept {
537 val = raw * (1.0f/65535.0f);
540 void Packet::Payload::WritePackU(const glm::vec3 &val, size_t off) noexcept {
541 WritePackU(val.x, off);
542 WritePackU(val.y, off + 2);
543 WritePackU(val.z, off + 4);
546 void Packet::Payload::ReadPackU(glm::vec3 &val, size_t off) const noexcept {
547 ReadPackU(val.x, off);
548 ReadPackU(val.y, off + 2);
549 ReadPackU(val.z, off + 4);
553 void Packet::Login::WritePlayerName(const string &name) noexcept {
554 WriteString(name, 0, 32);
557 void Packet::Login::ReadPlayerName(string &name) const noexcept {
558 ReadString(name, 0, 32);
561 void Packet::Join::WritePlayer(const Entity &player) noexcept {
562 Write(player.ID(), 0);
563 Write(player.GetState(), 4);
566 void Packet::Join::ReadPlayerID(uint32_t &id) const noexcept {
570 void Packet::Join::ReadPlayerState(EntityState &state) const noexcept {
574 void Packet::Join::WriteWorldName(const string &name) noexcept {
575 WriteString(name, 46, 32);
578 void Packet::Join::ReadWorldName(string &name) const noexcept {
579 ReadString(name, 46, 32);
582 void Packet::PlayerUpdate::WritePredictedState(const EntityState &state) noexcept {
586 void Packet::PlayerUpdate::ReadPredictedState(EntityState &state) const noexcept {
590 void Packet::PlayerUpdate::WriteMovement(const glm::vec3 &mov) noexcept {
594 void Packet::PlayerUpdate::ReadMovement(glm::vec3 &mov) const noexcept {
598 void Packet::PlayerUpdate::WriteActions(uint8_t actions) noexcept {
602 void Packet::PlayerUpdate::ReadActions(uint8_t &actions) const noexcept {
606 void Packet::PlayerUpdate::WriteSlot(uint8_t slot) noexcept {
610 void Packet::PlayerUpdate::ReadSlot(uint8_t &slot) const noexcept {
614 void Packet::SpawnEntity::WriteEntity(const Entity &e) noexcept {
617 Write(e.GetModel().GetModel().ID(), 4);
619 Write(uint32_t(0), 4);
621 Write(e.GetState(), 8);
622 Write(e.Bounds(), 50);
624 if (e.WorldCollidable()) {
628 WriteString(e.Name(), 78, 32);
631 void Packet::SpawnEntity::ReadEntityID(uint32_t &id) const noexcept {
635 void Packet::SpawnEntity::ReadModelID(uint32_t &id) const noexcept {
639 void Packet::SpawnEntity::ReadEntity(Entity &e) const noexcept {
648 ReadString(name, 78, 32);
652 e.WorldCollidable(flags & 1);
656 void Packet::DespawnEntity::WriteEntityID(uint32_t id) noexcept {
660 void Packet::DespawnEntity::ReadEntityID(uint32_t &id) const noexcept {
664 void Packet::EntityUpdate::WriteEntityCount(uint32_t count) noexcept {
668 void Packet::EntityUpdate::ReadEntityCount(uint32_t &count) const noexcept {
672 void Packet::EntityUpdate::WriteChunkBase(const glm::ivec3 &base) noexcept {
676 void Packet::EntityUpdate::ReadChunkBase(glm::ivec3 &base) const noexcept {
680 void Packet::EntityUpdate::WriteEntity(const Entity &entity, const glm::ivec3 &base, uint32_t num) noexcept {
681 uint32_t off = GetSize(num);
683 Write(entity.ID(), off);
684 Write(entity.GetState(), base, off + 4);
687 void Packet::EntityUpdate::ReadEntityID(uint32_t &id, uint32_t num) const noexcept {
688 uint32_t off = GetSize(num);
692 void Packet::EntityUpdate::ReadEntityState(EntityState &state, const glm::ivec3 &base, uint32_t num) const noexcept {
693 uint32_t off = GetSize(num);
694 Read(state, base, off + 4);
697 void Packet::PlayerCorrection::WritePacketSeq(std::uint16_t s) noexcept {
701 void Packet::PlayerCorrection::ReadPacketSeq(std::uint16_t &s) const noexcept {
705 void Packet::PlayerCorrection::WritePlayer(const Entity &player) noexcept {
706 Write(player.GetState(), 2);
709 void Packet::PlayerCorrection::ReadPlayerState(EntityState &state) const noexcept {
713 void Packet::ChunkBegin::WriteTransmissionId(uint32_t id) noexcept {
717 void Packet::ChunkBegin::ReadTransmissionId(uint32_t &id) const noexcept {
721 void Packet::ChunkBegin::WriteFlags(uint32_t f) noexcept {
725 void Packet::ChunkBegin::ReadFlags(uint32_t &f) const noexcept {
729 void Packet::ChunkBegin::WriteChunkCoords(const glm::ivec3 &pos) noexcept {
733 void Packet::ChunkBegin::ReadChunkCoords(glm::ivec3 &pos) const noexcept {
737 void Packet::ChunkBegin::WriteDataSize(uint32_t s) noexcept {
741 void Packet::ChunkBegin::ReadDataSize(uint32_t &s) const noexcept {
745 void Packet::ChunkData::WriteTransmissionId(uint32_t id) noexcept {
749 void Packet::ChunkData::ReadTransmissionId(uint32_t &id) const noexcept {
753 void Packet::ChunkData::WriteDataOffset(uint32_t o) noexcept {
757 void Packet::ChunkData::ReadDataOffset(uint32_t &o) const noexcept {
761 void Packet::ChunkData::WriteDataSize(uint32_t s) noexcept {
765 void Packet::ChunkData::ReadDataSize(uint32_t &s) const noexcept {
769 void Packet::ChunkData::WriteData(const uint8_t *d, size_t l) noexcept {
770 size_t len = min(length - 12, l);
771 memcpy(&data[12], d, len);
774 void Packet::ChunkData::ReadData(uint8_t *d, size_t l) const noexcept {
775 size_t len = min(length - 12, l);
776 memcpy(d, &data[12], len);
779 void Packet::BlockUpdate::WriteChunkCoords(const glm::ivec3 &coords) noexcept {
783 void Packet::BlockUpdate::ReadChunkCoords(glm::ivec3 &coords) const noexcept {
787 void Packet::BlockUpdate::WriteBlockCount(uint32_t count) noexcept {
791 void Packet::BlockUpdate::ReadBlockCount(uint32_t &count) const noexcept {
795 void Packet::BlockUpdate::WriteIndex(uint16_t index, uint32_t num) noexcept {
796 uint32_t off = GetSize(num);
800 void Packet::BlockUpdate::ReadIndex(uint16_t &index, uint32_t num) const noexcept {
801 uint32_t off = GetSize(num);
805 void Packet::BlockUpdate::WriteBlock(const Block &block, uint32_t num) noexcept {
806 uint32_t off = GetSize(num) + 2;
810 void Packet::BlockUpdate::ReadBlock(Block &block, uint32_t num) const noexcept {
811 uint32_t off = GetSize(num) + 2;
815 void Packet::Message::WriteType(uint8_t type) noexcept {
819 void Packet::Message::ReadType(uint8_t &type) const noexcept {
823 void Packet::Message::WriteReferral(uint32_t ref) noexcept {
827 void Packet::Message::ReadReferral(uint32_t &ref) const noexcept {
831 void Packet::Message::WriteMessage(const string &msg) noexcept {
832 WriteString(msg, 5, MAX_MESSAGE_LEN);
835 void Packet::Message::ReadMessage(string &msg) const noexcept {
836 ReadString(msg, 5, MAX_MESSAGE_LEN);
840 void ConnectionHandler::Handle(const UDPpacket &udp_pack) {
841 const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
842 switch (pack.Type()) {
843 case Packet::Ping::TYPE:
844 On(Packet::As<Packet::Ping>(udp_pack));
846 case Packet::Login::TYPE:
847 On(Packet::As<Packet::Login>(udp_pack));
849 case Packet::Join::TYPE:
850 On(Packet::As<Packet::Join>(udp_pack));
852 case Packet::Part::TYPE:
853 On(Packet::As<Packet::Part>(udp_pack));
855 case Packet::PlayerUpdate::TYPE:
856 On(Packet::As<Packet::PlayerUpdate>(udp_pack));
858 case Packet::SpawnEntity::TYPE:
859 On(Packet::As<Packet::SpawnEntity>(udp_pack));
861 case Packet::DespawnEntity::TYPE:
862 On(Packet::As<Packet::DespawnEntity>(udp_pack));
864 case Packet::EntityUpdate::TYPE:
865 On(Packet::As<Packet::EntityUpdate>(udp_pack));
867 case Packet::PlayerCorrection::TYPE:
868 On(Packet::As<Packet::PlayerCorrection>(udp_pack));
870 case Packet::ChunkBegin::TYPE:
871 On(Packet::As<Packet::ChunkBegin>(udp_pack));
873 case Packet::ChunkData::TYPE:
874 On(Packet::As<Packet::ChunkData>(udp_pack));
876 case Packet::BlockUpdate::TYPE:
877 On(Packet::As<Packet::BlockUpdate>(udp_pack));
879 case Packet::Message::TYPE:
880 On(Packet::As<Packet::Message>(udp_pack));
883 // drop unknown or unhandled packets