src/client/net.cpp

   1 #include "ChunkReceiver.hpp"
   2 #include "ChunkTransmission.hpp"
   3 #include "Client.hpp"
   4
   5 #include "../app/init.hpp"
   6 #include "../net/Packet.hpp"
   7 #include "../world/Chunk.hpp"
   8 #include "../world/ChunkStore.hpp"
   9
  10 #include <iostream>
  11 #include <zlib.h>
  12 #include <glm/gtx/io.hpp>
  13
  14 using namespace std;
  15
  16
  17 namespace blank {
  18 namespace client {
  19
  20
  21 ChunkReceiver::ChunkReceiver(ChunkStore &store)
  22 : store(store)
  23 , transmissions()
  24 , timer(5000) {
  25         timer.Start();
  26 }
  27
  28 ChunkReceiver::~ChunkReceiver() {
  29
  30 }
  31
  32 void ChunkReceiver::Update(int dt) {
  33         timer.Update(dt);
  34         for (ChunkTransmission &trans : transmissions) {
  35                 if (trans.active && (timer.Elapsed() - trans.last_update) > timer.Interval()) {
  36                         cout << "timeout for transmission of chunk " << trans.coords << endl;
  37                         trans.Clear();
  38                 }
  39         }
  40         if (transmissions.size() > 3) {
  41                 for (auto iter = transmissions.begin(), end = transmissions.end(); iter != end; ++iter) {
  42                         if (!iter->active) {
  43                                 transmissions.erase(iter);
  44                                 break;
  45                         }
  46                 }
  47         }
  48 }
  49
  50 void ChunkReceiver::Handle(const Packet::ChunkBegin &pack) {
  51         uint32_t id;
  52         pack.ReadTransmissionId(id);
  53         ChunkTransmission &trans = GetTransmission(id);
  54         pack.ReadFlags(trans.flags);
  55         pack.ReadChunkCoords(trans.coords);
  56         pack.ReadDataSize(trans.data_size);
  57         trans.last_update = timer.Elapsed();
  58         trans.header_received = true;
  59         Commit(trans);
  60 }
  61
  62 void ChunkReceiver::Handle(const Packet::ChunkData &pack) {
  63         uint32_t id, pos, size;
  64         pack.ReadTransmissionId(id);
  65         pack.ReadDataOffset(pos);
  66         if (pos >= sizeof(ChunkTransmission::buffer)) {
  67                 cout << "received chunk data offset outside of buffer size" << endl;
  68                 return;
  69         }
  70         pack.ReadDataSize(size);
  71         ChunkTransmission &trans = GetTransmission(id);
  72         size_t len = min(size_t(size), sizeof(ChunkTransmission::buffer) - pos);
  73         pack.ReadData(&trans.buffer[pos], len);
  74         // TODO: this method breaks when a packet arrives twice
  75         trans.data_received += len;
  76         trans.last_update = timer.Elapsed();
  77         Commit(trans);
  78 }
  79
  80 ChunkTransmission &ChunkReceiver::GetTransmission(uint32_t id) {
  81         // search for ongoing
  82         for (ChunkTransmission &trans : transmissions) {
  83                 if (trans.active && trans.id == id) {
  84                         return trans;
  85                 }
  86         }
  87         // search for unused
  88         for (ChunkTransmission &trans : transmissions) {
  89                 if (!trans.active) {
  90                         trans.active = true;
  91                         trans.id = id;
  92                         return trans;
  93                 }
  94         }
  95         // allocate new
  96         transmissions.emplace_back();
  97         transmissions.back().active = true;
  98         transmissions.back().id = id;
  99         return transmissions.back();
 100 }
 101
 102 void ChunkReceiver::Commit(ChunkTransmission &trans) {
 103         if (!trans.Complete()) return;
 104
 105         Chunk *chunk = store.Allocate(trans.coords);
 106         if (!chunk) {
 107                 // chunk no longer of interes, just drop the data
 108                 // it should probably be cached to disk, but not now :P
 109                 trans.Clear();
 110                 return;
 111         }
 112
 113         const Byte *src = &trans.buffer[0];
 114         uLong src_len = min(size_t(trans.data_size), sizeof(ChunkTransmission::buffer));
 115         Byte *dst = reinterpret_cast<Byte *>(chunk->BlockData());
 116         uLong dst_len = Chunk::BlockSize();
 117
 118         if (trans.Compressed()) {
 119                 if (uncompress(dst, &dst_len, src, src_len) != Z_OK) {
 120                         // omg, now what?
 121                         cout << "got corruped chunk data for " << trans.coords << endl;
 122                 }
 123         } else {
 124                 memcpy(dst, src, min(src_len, dst_len));
 125         }
 126         chunk->Invalidate();
 127         trans.Clear();
 128 }
 129
 130 ChunkTransmission::ChunkTransmission()
 131 : id(0)
 132 , flags(0)
 133 , coords()
 134 , data_size(0)
 135 , data_received(0)
 136 , last_update(0)
 137 , header_received(false)
 138 , active(false)
 139 , buffer() {
 140
 141 }
 142
 143 void ChunkTransmission::Clear() noexcept {
 144         data_size = 0;
 145         data_received = 0;
 146         last_update = 0;
 147         header_received = false;
 148         active = false;
 149 }
 150
 151 bool ChunkTransmission::Complete() const noexcept {
 152         return header_received && data_received == data_size;
 153 }
 154
 155 bool ChunkTransmission::Compressed() const noexcept {
 156         return flags & 1;
 157 }
 158
 159
 160 namespace {
 161
 162 UDPsocket client_bind(Uint16 port) {
 163         UDPsocket sock = SDLNet_UDP_Open(port);
 164         if (!sock) {
 165                 throw NetError("SDLNet_UDP_Open");
 166         }
 167         return sock;
 168 }
 169
 170 IPaddress client_resolve(const char *host, Uint16 port) {
 171         IPaddress addr;
 172         if (SDLNet_ResolveHost(&addr, host, port) != 0) {
 173                 throw NetError("SDLNet_ResolveHost");
 174         }
 175         return addr;
 176 }
 177
 178 }
 179
 180 Client::Client(const Config &conf)
 181 : conn(client_resolve(conf.host.c_str(), conf.port))
 182 , client_sock(client_bind(0))
 183 , client_pack{ -1, nullptr, 0 } {
 184         client_pack.data = new Uint8[sizeof(Packet)];
 185         client_pack.maxlen = sizeof(Packet);
 186         // establish connection
 187         SendPing();
 188 }
 189
 190 Client::~Client() {
 191         delete[] client_pack.data;
 192         SDLNet_UDP_Close(client_sock);
 193 }
 194
 195
 196 void Client::Handle() {
 197         int result = SDLNet_UDP_Recv(client_sock, &client_pack);
 198         while (result > 0) {
 199                 HandlePacket(client_pack);
 200                 result = SDLNet_UDP_Recv(client_sock, &client_pack);
 201         }
 202         if (result == -1) {
 203                 // a boo boo happened
 204                 throw NetError("SDLNet_UDP_Recv");
 205         }
 206 }
 207
 208 void Client::HandlePacket(const UDPpacket &udp_pack) {
 209         if (!conn.Matches(udp_pack.address)) {
 210                 // packet came from somewhere else, drop
 211                 return;
 212         }
 213         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 214         if (pack.header.tag != Packet::TAG) {
 215                 // mistagged packet, drop
 216                 return;
 217         }
 218
 219         conn.Received(udp_pack);
 220 }
 221
 222 void Client::Update(int dt) {
 223         conn.Update(dt);
 224         if (conn.ShouldPing()) {
 225                 SendPing();
 226         }
 227 }
 228
 229 uint16_t Client::SendPing() {
 230         return conn.SendPing(client_pack, client_sock);
 231 }
 232
 233 uint16_t Client::SendLogin(const string &name) {
 234         auto pack = Packet::Make<Packet::Login>(client_pack);
 235         pack.WritePlayerName(name);
 236         return conn.Send(client_pack, client_sock);
 237 }
 238
 239 uint16_t Client::SendPlayerUpdate(const Entity &player) {
 240         auto pack = Packet::Make<Packet::PlayerUpdate>(client_pack);
 241         pack.WritePlayer(player);
 242         return conn.Send(client_pack, client_sock);
 243 }
 244
 245 uint16_t Client::SendPart() {
 246         Packet::Make<Packet::Part>(client_pack);
 247         return conn.Send(client_pack, client_sock);
 248 }
 249
 250 }
 251 }