src/network/connection.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include <iomanip>
  21 #include <cerrno>
  22 #include <algorithm>
  23 #include <cmath>
  24 #include "connection.h"
  25 #include "serialization.h"
  26 #include "log.h"
  27 #include "porting.h"
  28 #include "network/connectionthreads.h"
  29 #include "network/networkpacket.h"
  30 #include "network/peerhandler.h"
  31 #include "util/serialize.h"
  32 #include "util/numeric.h"
  33 #include "util/string.h"
  34 #include "settings.h"
  35 #include "profiler.h"
  36
  37 namespace con
  38 {
  39
  40 /******************************************************************************/
  41 /* defines used for debugging and profiling                                   */
  42 /******************************************************************************/
  43 #ifdef NDEBUG
  44         #define LOG(a) a
  45         #define PROFILE(a)
  46 #else
  47         #if 0
  48         /* this mutex is used to achieve log message consistency */
  49         std::mutex log_message_mutex;
  50         #define LOG(a)                                                                 \
  51                 {                                                                          \
  52                 MutexAutoLock loglock(log_message_mutex);                                 \
  53                 a;                                                                         \
  54                 }
  55         #else
  56         // Prevent deadlocks until a solution is found after 5.2.0 (TODO)
  57         #define LOG(a) a
  58         #endif
  59
  60         #define PROFILE(a) a
  61 #endif
  62
  63 #define PING_TIMEOUT 5.0
  64
  65 BufferedPacket makePacket(Address &address, const SharedBuffer<u8> &data,
  66                 u32 protocol_id, session_t sender_peer_id, u8 channel)
  67 {
  68         u32 packet_size = data.getSize() + BASE_HEADER_SIZE;
  69         BufferedPacket p(packet_size);
  70         p.address = address;
  71
  72         writeU32(&p.data[0], protocol_id);
  73         writeU16(&p.data[4], sender_peer_id);
  74         writeU8(&p.data[6], channel);
  75
  76         memcpy(&p.data[BASE_HEADER_SIZE], *data, data.getSize());
  77
  78         return p;
  79 }
  80
  81 SharedBuffer<u8> makeOriginalPacket(const SharedBuffer<u8> &data)
  82 {
  83         u32 header_size = 1;
  84         u32 packet_size = data.getSize() + header_size;
  85         SharedBuffer<u8> b(packet_size);
  86
  87         writeU8(&(b[0]), PACKET_TYPE_ORIGINAL);
  88         if (data.getSize() > 0) {
  89                 memcpy(&(b[header_size]), *data, data.getSize());
  90         }
  91         return b;
  92 }
  93
  94 // Split data in chunks and add TYPE_SPLIT headers to them
  95 void makeSplitPacket(const SharedBuffer<u8> &data, u32 chunksize_max, u16 seqnum,
  96                 std::list<SharedBuffer<u8>> *chunks)
  97 {
  98         // Chunk packets, containing the TYPE_SPLIT header
  99         u32 chunk_header_size = 7;
 100         u32 maximum_data_size = chunksize_max - chunk_header_size;
 101         u32 start = 0;
 102         u32 end = 0;
 103         u32 chunk_num = 0;
 104         u16 chunk_count = 0;
 105         do {
 106                 end = start + maximum_data_size - 1;
 107                 if (end > data.getSize() - 1)
 108                         end = data.getSize() - 1;
 109
 110                 u32 payload_size = end - start + 1;
 111                 u32 packet_size = chunk_header_size + payload_size;
 112
 113                 SharedBuffer<u8> chunk(packet_size);
 114
 115                 writeU8(&chunk[0], PACKET_TYPE_SPLIT);
 116                 writeU16(&chunk[1], seqnum);
 117                 // [3] u16 chunk_count is written at next stage
 118                 writeU16(&chunk[5], chunk_num);
 119                 memcpy(&chunk[chunk_header_size], &data[start], payload_size);
 120
 121                 chunks->push_back(chunk);
 122                 chunk_count++;
 123
 124                 start = end + 1;
 125                 chunk_num++;
 126         }
 127         while (end != data.getSize() - 1);
 128
 129         for (SharedBuffer<u8> &chunk : *chunks) {
 130                 // Write chunk_count
 131                 writeU16(&(chunk[3]), chunk_count);
 132         }
 133 }
 134
 135 void makeAutoSplitPacket(const SharedBuffer<u8> &data, u32 chunksize_max,
 136                 u16 &split_seqnum, std::list<SharedBuffer<u8>> *list)
 137 {
 138         u32 original_header_size = 1;
 139
 140         if (data.getSize() + original_header_size > chunksize_max) {
 141                 makeSplitPacket(data, chunksize_max, split_seqnum, list);
 142                 split_seqnum++;
 143                 return;
 144         }
 145
 146         list->push_back(makeOriginalPacket(data));
 147 }
 148
 149 SharedBuffer<u8> makeReliablePacket(const SharedBuffer<u8> &data, u16 seqnum)
 150 {
 151         u32 header_size = 3;
 152         u32 packet_size = data.getSize() + header_size;
 153         SharedBuffer<u8> b(packet_size);
 154
 155         writeU8(&b[0], PACKET_TYPE_RELIABLE);
 156         writeU16(&b[1], seqnum);
 157
 158         memcpy(&b[header_size], *data, data.getSize());
 159
 160         return b;
 161 }
 162
 163 /*
 164         ReliablePacketBuffer
 165 */
 166
 167 void ReliablePacketBuffer::print()
 168 {
 169         MutexAutoLock listlock(m_list_mutex);
 170         LOG(dout_con<<"Dump of ReliablePacketBuffer:" << std::endl);
 171         unsigned int index = 0;
 172         for (BufferedPacket &bufferedPacket : m_list) {
 173                 u16 s = readU16(&(bufferedPacket.data[BASE_HEADER_SIZE+1]));
 174                 LOG(dout_con<<index<< ":" << s << std::endl);
 175                 index++;
 176         }
 177 }
 178
 179 bool ReliablePacketBuffer::empty()
 180 {
 181         MutexAutoLock listlock(m_list_mutex);
 182         return m_list.empty();
 183 }
 184
 185 u32 ReliablePacketBuffer::size()
 186 {
 187         MutexAutoLock listlock(m_list_mutex);
 188         return m_list.size();
 189 }
 190
 191 RPBSearchResult ReliablePacketBuffer::findPacket(u16 seqnum)
 192 {
 193         std::list<BufferedPacket>::iterator i = m_list.begin();
 194         for(; i != m_list.end(); ++i)
 195         {
 196                 u16 s = readU16(&(i->data[BASE_HEADER_SIZE+1]));
 197                 if (s == seqnum)
 198                         break;
 199         }
 200         return i;
 201 }
 202
 203 RPBSearchResult ReliablePacketBuffer::notFound()
 204 {
 205         return m_list.end();
 206 }
 207
 208 bool ReliablePacketBuffer::getFirstSeqnum(u16& result)
 209 {
 210         MutexAutoLock listlock(m_list_mutex);
 211         if (m_list.empty())
 212                 return false;
 213         const BufferedPacket &p = *m_list.begin();
 214         result = readU16(&p.data[BASE_HEADER_SIZE + 1]);
 215         return true;
 216 }
 217
 218 BufferedPacket ReliablePacketBuffer::popFirst()
 219 {
 220         MutexAutoLock listlock(m_list_mutex);
 221         if (m_list.empty())
 222                 throw NotFoundException("Buffer is empty");
 223         BufferedPacket p = *m_list.begin();
 224         m_list.erase(m_list.begin());
 225
 226         if (m_list.empty()) {
 227                 m_oldest_non_answered_ack = 0;
 228         } else {
 229                 m_oldest_non_answered_ack =
 230                                 readU16(&m_list.begin()->data[BASE_HEADER_SIZE + 1]);
 231         }
 232         return p;
 233 }
 234
 235 BufferedPacket ReliablePacketBuffer::popSeqnum(u16 seqnum)
 236 {
 237         MutexAutoLock listlock(m_list_mutex);
 238         RPBSearchResult r = findPacket(seqnum);
 239         if (r == notFound()) {
 240                 LOG(dout_con<<"Sequence number: " << seqnum
 241                                 << " not found in reliable buffer"<<std::endl);
 242                 throw NotFoundException("seqnum not found in buffer");
 243         }
 244         BufferedPacket p = *r;
 245
 246
 247         RPBSearchResult next = r;
 248         ++next;
 249         if (next != notFound()) {
 250                 u16 s = readU16(&(next->data[BASE_HEADER_SIZE+1]));
 251                 m_oldest_non_answered_ack = s;
 252         }
 253
 254         m_list.erase(r);
 255
 256         if (m_list.empty()) {
 257                 m_oldest_non_answered_ack = 0;
 258         } else {
 259                 m_oldest_non_answered_ack =
 260                                 readU16(&m_list.begin()->data[BASE_HEADER_SIZE + 1]);
 261         }
 262         return p;
 263 }
 264
 265 void ReliablePacketBuffer::insert(BufferedPacket &p, u16 next_expected)
 266 {
 267         MutexAutoLock listlock(m_list_mutex);
 268         if (p.data.getSize() < BASE_HEADER_SIZE + 3) {
 269                 errorstream << "ReliablePacketBuffer::insert(): Invalid data size for "
 270                         "reliable packet" << std::endl;
 271                 return;
 272         }
 273         u8 type = readU8(&p.data[BASE_HEADER_SIZE + 0]);
 274         if (type != PACKET_TYPE_RELIABLE) {
 275                 errorstream << "ReliablePacketBuffer::insert(): type is not reliable"
 276                         << std::endl;
 277                 return;
 278         }
 279         u16 seqnum = readU16(&p.data[BASE_HEADER_SIZE + 1]);
 280
 281         if (!seqnum_in_window(seqnum, next_expected, MAX_RELIABLE_WINDOW_SIZE)) {
 282                 errorstream << "ReliablePacketBuffer::insert(): seqnum is outside of "
 283                         "expected window " << std::endl;
 284                 return;
 285         }
 286         if (seqnum == next_expected) {
 287                 errorstream << "ReliablePacketBuffer::insert(): seqnum is next expected"
 288                         << std::endl;
 289                 return;
 290         }
 291
 292         sanity_check(m_list.size() <= SEQNUM_MAX); // FIXME: Handle the error?
 293
 294         // Find the right place for the packet and insert it there
 295         // If list is empty, just add it
 296         if (m_list.empty())
 297         {
 298                 m_list.push_back(p);
 299                 m_oldest_non_answered_ack = seqnum;
 300                 // Done.
 301                 return;
 302         }
 303
 304         // Otherwise find the right place
 305         std::list<BufferedPacket>::iterator i = m_list.begin();
 306         // Find the first packet in the list which has a higher seqnum
 307         u16 s = readU16(&(i->data[BASE_HEADER_SIZE+1]));
 308
 309         /* case seqnum is smaller then next_expected seqnum */
 310         /* this is true e.g. on wrap around */
 311         if (seqnum < next_expected) {
 312                 while(((s < seqnum) || (s >= next_expected)) && (i != m_list.end())) {
 313                         ++i;
 314                         if (i != m_list.end())
 315                                 s = readU16(&(i->data[BASE_HEADER_SIZE+1]));
 316                 }
 317         }
 318         /* non wrap around case (at least for incoming and next_expected */
 319         else
 320         {
 321                 while(((s < seqnum) && (s >= next_expected)) && (i != m_list.end())) {
 322                         ++i;
 323                         if (i != m_list.end())
 324                                 s = readU16(&(i->data[BASE_HEADER_SIZE+1]));
 325                 }
 326         }
 327
 328         if (s == seqnum) {
 329                 /* nothing to do this seems to be a resent packet */
 330                 /* for paranoia reason data should be compared */
 331                 if (
 332                         (readU16(&(i->data[BASE_HEADER_SIZE+1])) != seqnum) ||
 333                         (i->data.getSize() != p.data.getSize()) ||
 334                         (i->address != p.address)
 335                         )
 336                 {
 337                         /* if this happens your maximum transfer window may be to big */
 338                         fprintf(stderr,
 339                                         "Duplicated seqnum %d non matching packet detected:\n",
 340                                         seqnum);
 341                         fprintf(stderr, "Old: seqnum: %05d size: %04d, address: %s\n",
 342                                         readU16(&(i->data[BASE_HEADER_SIZE+1])),i->data.getSize(),
 343                                         i->address.serializeString().c_str());
 344                         fprintf(stderr, "New: seqnum: %05d size: %04u, address: %s\n",
 345                                         readU16(&(p.data[BASE_HEADER_SIZE+1])),p.data.getSize(),
 346                                         p.address.serializeString().c_str());
 347                         throw IncomingDataCorruption("duplicated packet isn't same as original one");
 348                 }
 349         }
 350         /* insert or push back */
 351         else if (i != m_list.end()) {
 352                 m_list.insert(i, p);
 353         } else {
 354                 m_list.push_back(p);
 355         }
 356
 357         /* update last packet number */
 358         m_oldest_non_answered_ack = readU16(&(*m_list.begin()).data[BASE_HEADER_SIZE+1]);
 359 }
 360
 361 void ReliablePacketBuffer::incrementTimeouts(float dtime)
 362 {
 363         MutexAutoLock listlock(m_list_mutex);
 364         for (BufferedPacket &bufferedPacket : m_list) {
 365                 bufferedPacket.time += dtime;
 366                 bufferedPacket.totaltime += dtime;
 367         }
 368 }
 369
 370 std::list<BufferedPacket> ReliablePacketBuffer::getTimedOuts(float timeout,
 371                                                                                                         unsigned int max_packets)
 372 {
 373         MutexAutoLock listlock(m_list_mutex);
 374         std::list<BufferedPacket> timed_outs;
 375         for (BufferedPacket &bufferedPacket : m_list) {
 376                 if (bufferedPacket.time >= timeout) {
 377                         timed_outs.push_back(bufferedPacket);
 378
 379                         //this packet will be sent right afterwards reset timeout here
 380                         bufferedPacket.time = 0.0f;
 381                         if (timed_outs.size() >= max_packets)
 382                                 break;
 383                 }
 384         }
 385         return timed_outs;
 386 }
 387
 388 /*
 389         IncomingSplitPacket
 390 */
 391
 392 bool IncomingSplitPacket::insert(u32 chunk_num, SharedBuffer<u8> &chunkdata)
 393 {
 394         sanity_check(chunk_num < chunk_count);
 395
 396         // If chunk already exists, ignore it.
 397         // Sometimes two identical packets may arrive when there is network
 398         // lag and the server re-sends stuff.
 399         if (chunks.find(chunk_num) != chunks.end())
 400                 return false;
 401
 402         // Set chunk data in buffer
 403         chunks[chunk_num] = chunkdata;
 404
 405         return true;
 406 }
 407
 408 SharedBuffer<u8> IncomingSplitPacket::reassemble()
 409 {
 410         sanity_check(allReceived());
 411
 412         // Calculate total size
 413         u32 totalsize = 0;
 414         for (const auto &chunk : chunks)
 415                 totalsize += chunk.second.getSize();
 416
 417         SharedBuffer<u8> fulldata(totalsize);
 418
 419         // Copy chunks to data buffer
 420         u32 start = 0;
 421         for (u32 chunk_i = 0; chunk_i < chunk_count; chunk_i++) {
 422                 const SharedBuffer<u8> &buf = chunks[chunk_i];
 423                 memcpy(&fulldata[start], *buf, buf.getSize());
 424                 start += buf.getSize();
 425         }
 426
 427         return fulldata;
 428 }
 429
 430 /*
 431         IncomingSplitBuffer
 432 */
 433
 434 IncomingSplitBuffer::~IncomingSplitBuffer()
 435 {
 436         MutexAutoLock listlock(m_map_mutex);
 437         for (auto &i : m_buf) {
 438                 delete i.second;
 439         }
 440 }
 441
 442 SharedBuffer<u8> IncomingSplitBuffer::insert(const BufferedPacket &p, bool reliable)
 443 {
 444         MutexAutoLock listlock(m_map_mutex);
 445         u32 headersize = BASE_HEADER_SIZE + 7;
 446         if (p.data.getSize() < headersize) {
 447                 errorstream << "Invalid data size for split packet" << std::endl;
 448                 return SharedBuffer<u8>();
 449         }
 450         u8 type = readU8(&p.data[BASE_HEADER_SIZE+0]);
 451         u16 seqnum = readU16(&p.data[BASE_HEADER_SIZE+1]);
 452         u16 chunk_count = readU16(&p.data[BASE_HEADER_SIZE+3]);
 453         u16 chunk_num = readU16(&p.data[BASE_HEADER_SIZE+5]);
 454
 455         if (type != PACKET_TYPE_SPLIT) {
 456                 errorstream << "IncomingSplitBuffer::insert(): type is not split"
 457                         << std::endl;
 458                 return SharedBuffer<u8>();
 459         }
 460         if (chunk_num >= chunk_count) {
 461                 errorstream << "IncomingSplitBuffer::insert(): chunk_num=" << chunk_num
 462                                 << " >= chunk_count=" << chunk_count << std::endl;
 463                 return SharedBuffer<u8>();
 464         }
 465
 466         // Add if doesn't exist
 467         IncomingSplitPacket *sp;
 468         if (m_buf.find(seqnum) == m_buf.end()) {
 469                 sp = new IncomingSplitPacket(chunk_count, reliable);
 470                 m_buf[seqnum] = sp;
 471         } else {
 472                 sp = m_buf[seqnum];
 473         }
 474
 475         if (chunk_count != sp->chunk_count) {
 476                 errorstream << "IncomingSplitBuffer::insert(): chunk_count="
 477                                 << chunk_count << " != sp->chunk_count=" << sp->chunk_count
 478                                 << std::endl;
 479                 return SharedBuffer<u8>();
 480         }
 481         if (reliable != sp->reliable)
 482                 LOG(derr_con<<"Connection: WARNING: reliable="<<reliable
 483                                 <<" != sp->reliable="<<sp->reliable
 484                                 <<std::endl);
 485
 486         // Cut chunk data out of packet
 487         u32 chunkdatasize = p.data.getSize() - headersize;
 488         SharedBuffer<u8> chunkdata(chunkdatasize);
 489         memcpy(*chunkdata, &(p.data[headersize]), chunkdatasize);
 490
 491         if (!sp->insert(chunk_num, chunkdata))
 492                 return SharedBuffer<u8>();
 493
 494         // If not all chunks are received, return empty buffer
 495         if (!sp->allReceived())
 496                 return SharedBuffer<u8>();
 497
 498         SharedBuffer<u8> fulldata = sp->reassemble();
 499
 500         // Remove sp from buffer
 501         m_buf.erase(seqnum);
 502         delete sp;
 503
 504         return fulldata;
 505 }
 506
 507 void IncomingSplitBuffer::removeUnreliableTimedOuts(float dtime, float timeout)
 508 {
 509         std::deque<u16> remove_queue;
 510         {
 511                 MutexAutoLock listlock(m_map_mutex);
 512                 for (auto &i : m_buf) {
 513                         IncomingSplitPacket *p = i.second;
 514                         // Reliable ones are not removed by timeout
 515                         if (p->reliable)
 516                                 continue;
 517                         p->time += dtime;
 518                         if (p->time >= timeout)
 519                                 remove_queue.push_back(i.first);
 520                 }
 521         }
 522         for (u16 j : remove_queue) {
 523                 MutexAutoLock listlock(m_map_mutex);
 524                 LOG(dout_con<<"NOTE: Removing timed out unreliable split packet"<<std::endl);
 525                 delete m_buf[j];
 526                 m_buf.erase(j);
 527         }
 528 }
 529
 530 /*
 531         ConnectionCommand
 532  */
 533
 534 void ConnectionCommand::send(session_t peer_id_, u8 channelnum_, NetworkPacket *pkt,
 535         bool reliable_)
 536 {
 537         type = CONNCMD_SEND;
 538         peer_id = peer_id_;
 539         channelnum = channelnum_;
 540         data = pkt->oldForgePacket();
 541         reliable = reliable_;
 542 }
 543
 544 /*
 545         Channel
 546 */
 547
 548 u16 Channel::readNextIncomingSeqNum()
 549 {
 550         MutexAutoLock internal(m_internal_mutex);
 551         return next_incoming_seqnum;
 552 }
 553
 554 u16 Channel::incNextIncomingSeqNum()
 555 {
 556         MutexAutoLock internal(m_internal_mutex);
 557         u16 retval = next_incoming_seqnum;
 558         next_incoming_seqnum++;
 559         return retval;
 560 }
 561
 562 u16 Channel::readNextSplitSeqNum()
 563 {
 564         MutexAutoLock internal(m_internal_mutex);
 565         return next_outgoing_split_seqnum;
 566 }
 567 void Channel::setNextSplitSeqNum(u16 seqnum)
 568 {
 569         MutexAutoLock internal(m_internal_mutex);
 570         next_outgoing_split_seqnum = seqnum;
 571 }
 572
 573 u16 Channel::getOutgoingSequenceNumber(bool& successful)
 574 {
 575         MutexAutoLock internal(m_internal_mutex);
 576         u16 retval = next_outgoing_seqnum;
 577         u16 lowest_unacked_seqnumber;
 578
 579         /* shortcut if there ain't any packet in outgoing list */
 580         if (outgoing_reliables_sent.empty())
 581         {
 582                 next_outgoing_seqnum++;
 583                 return retval;
 584         }
 585
 586         if (outgoing_reliables_sent.getFirstSeqnum(lowest_unacked_seqnumber))
 587         {
 588                 if (lowest_unacked_seqnumber < next_outgoing_seqnum) {
 589                         // ugly cast but this one is required in order to tell compiler we
 590                         // know about difference of two unsigned may be negative in general
 591                         // but we already made sure it won't happen in this case
 592                         if (((u16)(next_outgoing_seqnum - lowest_unacked_seqnumber)) > window_size) {
 593                                 successful = false;
 594                                 return 0;
 595                         }
 596                 }
 597                 else {
 598                         // ugly cast but this one is required in order to tell compiler we
 599                         // know about difference of two unsigned may be negative in general
 600                         // but we already made sure it won't happen in this case
 601                         if ((next_outgoing_seqnum + (u16)(SEQNUM_MAX - lowest_unacked_seqnumber)) >
 602                                 window_size) {
 603                                 successful = false;
 604                                 return 0;
 605                         }
 606                 }
 607         }
 608
 609         next_outgoing_seqnum++;
 610         return retval;
 611 }
 612
 613 u16 Channel::readOutgoingSequenceNumber()
 614 {
 615         MutexAutoLock internal(m_internal_mutex);
 616         return next_outgoing_seqnum;
 617 }
 618
 619 bool Channel::putBackSequenceNumber(u16 seqnum)
 620 {
 621         if (((seqnum + 1) % (SEQNUM_MAX+1)) == next_outgoing_seqnum) {
 622
 623                 next_outgoing_seqnum = seqnum;
 624                 return true;
 625         }
 626         return false;
 627 }
 628
 629 void Channel::UpdateBytesSent(unsigned int bytes, unsigned int packets)
 630 {
 631         MutexAutoLock internal(m_internal_mutex);
 632         current_bytes_transfered += bytes;
 633         current_packet_successful += packets;
 634 }
 635
 636 void Channel::UpdateBytesReceived(unsigned int bytes) {
 637         MutexAutoLock internal(m_internal_mutex);
 638         current_bytes_received += bytes;
 639 }
 640
 641 void Channel::UpdateBytesLost(unsigned int bytes)
 642 {
 643         MutexAutoLock internal(m_internal_mutex);
 644         current_bytes_lost += bytes;
 645 }
 646
 647
 648 void Channel::UpdatePacketLossCounter(unsigned int count)
 649 {
 650         MutexAutoLock internal(m_internal_mutex);
 651         current_packet_loss += count;
 652 }
 653
 654 void Channel::UpdatePacketTooLateCounter()
 655 {
 656         MutexAutoLock internal(m_internal_mutex);
 657         current_packet_too_late++;
 658 }
 659
 660 void Channel::UpdateTimers(float dtime)
 661 {
 662         bpm_counter += dtime;
 663         packet_loss_counter += dtime;
 664
 665         if (packet_loss_counter > 1.0f) {
 666                 packet_loss_counter -= 1.0f;
 667
 668                 unsigned int packet_loss = 11; /* use a neutral value for initialization */
 669                 unsigned int packets_successful = 0;
 670                 //unsigned int packet_too_late = 0;
 671
 672                 bool reasonable_amount_of_data_transmitted = false;
 673
 674                 {
 675                         MutexAutoLock internal(m_internal_mutex);
 676                         packet_loss = current_packet_loss;
 677                         //packet_too_late = current_packet_too_late;
 678                         packets_successful = current_packet_successful;
 679
 680                         if (current_bytes_transfered > (unsigned int) (window_size*512/2)) {
 681                                 reasonable_amount_of_data_transmitted = true;
 682                         }
 683                         current_packet_loss = 0;
 684                         current_packet_too_late = 0;
 685                         current_packet_successful = 0;
 686                 }
 687
 688                 /* dynamic window size */
 689                 float successful_to_lost_ratio = 0.0f;
 690                 bool done = false;
 691
 692                 if (packets_successful > 0) {
 693                         successful_to_lost_ratio = packet_loss/packets_successful;
 694                 } else if (packet_loss > 0) {
 695                         window_size = std::max(
 696                                         (window_size - 10),
 697                                         MIN_RELIABLE_WINDOW_SIZE);
 698                         done = true;
 699                 }
 700
 701                 if (!done) {
 702                         if ((successful_to_lost_ratio < 0.01f) &&
 703                                 (window_size < MAX_RELIABLE_WINDOW_SIZE)) {
 704                                 /* don't even think about increasing if we didn't even
 705                                  * use major parts of our window */
 706                                 if (reasonable_amount_of_data_transmitted)
 707                                         window_size = std::min(
 708                                                         (window_size + 100),
 709                                                         MAX_RELIABLE_WINDOW_SIZE);
 710                         } else if ((successful_to_lost_ratio < 0.05f) &&
 711                                         (window_size < MAX_RELIABLE_WINDOW_SIZE)) {
 712                                 /* don't even think about increasing if we didn't even
 713                                  * use major parts of our window */
 714                                 if (reasonable_amount_of_data_transmitted)
 715                                         window_size = std::min(
 716                                                         (window_size + 50),
 717                                                         MAX_RELIABLE_WINDOW_SIZE);
 718                         } else if (successful_to_lost_ratio > 0.15f) {
 719                                 window_size = std::max(
 720                                                 (window_size - 100),
 721                                                 MIN_RELIABLE_WINDOW_SIZE);
 722                         } else if (successful_to_lost_ratio > 0.1f) {
 723                                 window_size = std::max(
 724                                                 (window_size - 50),
 725                                                 MIN_RELIABLE_WINDOW_SIZE);
 726                         }
 727                 }
 728         }
 729
 730         if (bpm_counter > 10.0f) {
 731                 {
 732                         MutexAutoLock internal(m_internal_mutex);
 733                         cur_kbps                 =
 734                                         (((float) current_bytes_transfered)/bpm_counter)/1024.0f;
 735                         current_bytes_transfered = 0;
 736                         cur_kbps_lost            =
 737                                         (((float) current_bytes_lost)/bpm_counter)/1024.0f;
 738                         current_bytes_lost       = 0;
 739                         cur_incoming_kbps        =
 740                                         (((float) current_bytes_received)/bpm_counter)/1024.0f;
 741                         current_bytes_received   = 0;
 742                         bpm_counter              = 0.0f;
 743                 }
 744
 745                 if (cur_kbps > max_kbps) {
 746                         max_kbps = cur_kbps;
 747                 }
 748
 749                 if (cur_kbps_lost > max_kbps_lost) {
 750                         max_kbps_lost = cur_kbps_lost;
 751                 }
 752
 753                 if (cur_incoming_kbps > max_incoming_kbps) {
 754                         max_incoming_kbps = cur_incoming_kbps;
 755                 }
 756
 757                 rate_samples       = MYMIN(rate_samples+1,10);
 758                 float old_fraction = ((float) (rate_samples-1) )/( (float) rate_samples);
 759                 avg_kbps           = avg_kbps * old_fraction +
 760                                 cur_kbps * (1.0 - old_fraction);
 761                 avg_kbps_lost      = avg_kbps_lost * old_fraction +
 762                                 cur_kbps_lost * (1.0 - old_fraction);
 763                 avg_incoming_kbps  = avg_incoming_kbps * old_fraction +
 764                                 cur_incoming_kbps * (1.0 - old_fraction);
 765         }
 766 }
 767
 768
 769 /*
 770         Peer
 771 */
 772
 773 PeerHelper::PeerHelper(Peer* peer) :
 774         m_peer(peer)
 775 {
 776         if (peer && !peer->IncUseCount())
 777                 m_peer = nullptr;
 778 }
 779
 780 PeerHelper::~PeerHelper()
 781 {
 782         if (m_peer)
 783                 m_peer->DecUseCount();
 784
 785         m_peer = nullptr;
 786 }
 787
 788 PeerHelper& PeerHelper::operator=(Peer* peer)
 789 {
 790         m_peer = peer;
 791         if (peer && !peer->IncUseCount())
 792                 m_peer = nullptr;
 793         return *this;
 794 }
 795
 796 Peer* PeerHelper::operator->() const
 797 {
 798         return m_peer;
 799 }
 800
 801 Peer* PeerHelper::operator&() const
 802 {
 803         return m_peer;
 804 }
 805
 806 bool PeerHelper::operator!()
 807 {
 808         return ! m_peer;
 809 }
 810
 811 bool PeerHelper::operator!=(void* ptr)
 812 {
 813         return ((void*) m_peer != ptr);
 814 }
 815
 816 bool Peer::IncUseCount()
 817 {
 818         MutexAutoLock lock(m_exclusive_access_mutex);
 819
 820         if (!m_pending_deletion) {
 821                 this->m_usage++;
 822                 return true;
 823         }
 824
 825         return false;
 826 }
 827
 828 void Peer::DecUseCount()
 829 {
 830         {
 831                 MutexAutoLock lock(m_exclusive_access_mutex);
 832                 sanity_check(m_usage > 0);
 833                 m_usage--;
 834
 835                 if (!((m_pending_deletion) && (m_usage == 0)))
 836                         return;
 837         }
 838         delete this;
 839 }
 840
 841 void Peer::RTTStatistics(float rtt, const std::string &profiler_id,
 842                 unsigned int num_samples) {
 843
 844         if (m_last_rtt > 0) {
 845                 /* set min max values */
 846                 if (rtt < m_rtt.min_rtt)
 847                         m_rtt.min_rtt = rtt;
 848                 if (rtt >= m_rtt.max_rtt)
 849                         m_rtt.max_rtt = rtt;
 850
 851                 /* do average calculation */
 852                 if (m_rtt.avg_rtt < 0.0)
 853                         m_rtt.avg_rtt  = rtt;
 854                 else
 855                         m_rtt.avg_rtt  = m_rtt.avg_rtt * (num_samples/(num_samples-1)) +
 856                                                                 rtt * (1/num_samples);
 857
 858                 /* do jitter calculation */
 859
 860                 //just use some neutral value at beginning
 861                 float jitter = m_rtt.jitter_min;
 862
 863                 if (rtt > m_last_rtt)
 864                         jitter = rtt-m_last_rtt;
 865
 866                 if (rtt <= m_last_rtt)
 867                         jitter = m_last_rtt - rtt;
 868
 869                 if (jitter < m_rtt.jitter_min)
 870                         m_rtt.jitter_min = jitter;
 871                 if (jitter >= m_rtt.jitter_max)
 872                         m_rtt.jitter_max = jitter;
 873
 874                 if (m_rtt.jitter_avg < 0.0)
 875                         m_rtt.jitter_avg  = jitter;
 876                 else
 877                         m_rtt.jitter_avg  = m_rtt.jitter_avg * (num_samples/(num_samples-1)) +
 878                                                                 jitter * (1/num_samples);
 879
 880                 if (!profiler_id.empty()) {
 881                         g_profiler->graphAdd(profiler_id + " RTT [ms]", rtt * 1000.f);
 882                         g_profiler->graphAdd(profiler_id + " jitter [ms]", jitter * 1000.f);
 883                 }
 884         }
 885         /* save values required for next loop */
 886         m_last_rtt = rtt;
 887 }
 888
 889 bool Peer::isTimedOut(float timeout)
 890 {
 891         MutexAutoLock lock(m_exclusive_access_mutex);
 892         u64 current_time = porting::getTimeMs();
 893
 894         float dtime = CALC_DTIME(m_last_timeout_check,current_time);
 895         m_last_timeout_check = current_time;
 896
 897         m_timeout_counter += dtime;
 898
 899         return m_timeout_counter > timeout;
 900 }
 901
 902 void Peer::Drop()
 903 {
 904         {
 905                 MutexAutoLock usage_lock(m_exclusive_access_mutex);
 906                 m_pending_deletion = true;
 907                 if (m_usage != 0)
 908                         return;
 909         }
 910
 911         PROFILE(std::stringstream peerIdentifier1);
 912         PROFILE(peerIdentifier1 << "runTimeouts[" << m_connection->getDesc()
 913                         << ";" << id << ";RELIABLE]");
 914         PROFILE(g_profiler->remove(peerIdentifier1.str()));
 915         PROFILE(std::stringstream peerIdentifier2);
 916         PROFILE(peerIdentifier2 << "sendPackets[" << m_connection->getDesc()
 917                         << ";" << id << ";RELIABLE]");
 918         PROFILE(ScopeProfiler peerprofiler(g_profiler, peerIdentifier2.str(), SPT_AVG));
 919
 920         delete this;
 921 }
 922
 923 UDPPeer::UDPPeer(u16 a_id, Address a_address, Connection* connection) :
 924         Peer(a_address,a_id,connection)
 925 {
 926         for (Channel &channel : channels)
 927                 channel.setWindowSize(START_RELIABLE_WINDOW_SIZE);
 928 }
 929
 930 bool UDPPeer::getAddress(MTProtocols type,Address& toset)
 931 {
 932         if ((type == MTP_UDP) || (type == MTP_MINETEST_RELIABLE_UDP) || (type == MTP_PRIMARY))
 933         {
 934                 toset = address;
 935                 return true;
 936         }
 937
 938         return false;
 939 }
 940
 941 void UDPPeer::reportRTT(float rtt)
 942 {
 943         if (rtt < 0.0) {
 944                 return;
 945         }
 946         RTTStatistics(rtt,"rudp",MAX_RELIABLE_WINDOW_SIZE*10);
 947
 948         float timeout = getStat(AVG_RTT) * RESEND_TIMEOUT_FACTOR;
 949         if (timeout < RESEND_TIMEOUT_MIN)
 950                 timeout = RESEND_TIMEOUT_MIN;
 951         if (timeout > RESEND_TIMEOUT_MAX)
 952                 timeout = RESEND_TIMEOUT_MAX;
 953
 954         MutexAutoLock usage_lock(m_exclusive_access_mutex);
 955         resend_timeout = timeout;
 956 }
 957
 958 bool UDPPeer::Ping(float dtime,SharedBuffer<u8>& data)
 959 {
 960         m_ping_timer += dtime;
 961         if (m_ping_timer >= PING_TIMEOUT)
 962         {
 963                 // Create and send PING packet
 964                 writeU8(&data[0], PACKET_TYPE_CONTROL);
 965                 writeU8(&data[1], CONTROLTYPE_PING);
 966                 m_ping_timer = 0.0;
 967                 return true;
 968         }
 969         return false;
 970 }
 971
 972 void UDPPeer::PutReliableSendCommand(ConnectionCommand &c,
 973                 unsigned int max_packet_size)
 974 {
 975         if (m_pending_disconnect)
 976                 return;
 977
 978         Channel &chan = channels[c.channelnum];
 979
 980         if (chan.queued_commands.empty() &&
 981                         /* don't queue more packets then window size */
 982                         (chan.queued_reliables.size() < chan.getWindowSize() / 2)) {
 983                 LOG(dout_con<<m_connection->getDesc()
 984                                 <<" processing reliable command for peer id: " << c.peer_id
 985                                 <<" data size: " << c.data.getSize() << std::endl);
 986                 if (!processReliableSendCommand(c,max_packet_size)) {
 987                         chan.queued_commands.push_back(c);
 988                 }
 989         }
 990         else {
 991                 LOG(dout_con<<m_connection->getDesc()
 992                                 <<" Queueing reliable command for peer id: " << c.peer_id
 993                                 <<" data size: " << c.data.getSize() <<std::endl);
 994                 chan.queued_commands.push_back(c);
 995                 if (chan.queued_commands.size() >= chan.getWindowSize() / 2) {
 996                         LOG(derr_con << m_connection->getDesc()
 997                                         << "Possible packet stall to peer id: " << c.peer_id
 998                                         << " queued_commands=" << chan.queued_commands.size()
 999                                         << std::endl);
1000                 }
1001         }
1002 }
1003
1004 bool UDPPeer::processReliableSendCommand(
1005                                 ConnectionCommand &c,
1006                                 unsigned int max_packet_size)
1007 {
1008         if (m_pending_disconnect)
1009                 return true;
1010
1011         Channel &chan = channels[c.channelnum];
1012
1013         u32 chunksize_max = max_packet_size
1014                                                         - BASE_HEADER_SIZE
1015                                                         - RELIABLE_HEADER_SIZE;
1016
1017         sanity_check(c.data.getSize() < MAX_RELIABLE_WINDOW_SIZE*512);
1018
1019         std::list<SharedBuffer<u8>> originals;
1020         u16 split_sequence_number = chan.readNextSplitSeqNum();
1021
1022         if (c.raw) {
1023                 originals.emplace_back(c.data);
1024         } else {
1025                 makeAutoSplitPacket(c.data, chunksize_max,split_sequence_number, &originals);
1026                 chan.setNextSplitSeqNum(split_sequence_number);
1027         }
1028
1029         bool have_sequence_number = true;
1030         bool have_initial_sequence_number = false;
1031         std::queue<BufferedPacket> toadd;
1032         volatile u16 initial_sequence_number = 0;
1033
1034         for (SharedBuffer<u8> &original : originals) {
1035                 u16 seqnum = chan.getOutgoingSequenceNumber(have_sequence_number);
1036
1037                 /* oops, we don't have enough sequence numbers to send this packet */
1038                 if (!have_sequence_number)
1039                         break;
1040
1041                 if (!have_initial_sequence_number)
1042                 {
1043                         initial_sequence_number = seqnum;
1044                         have_initial_sequence_number = true;
1045                 }
1046
1047                 SharedBuffer<u8> reliable = makeReliablePacket(original, seqnum);
1048
1049                 // Add base headers and make a packet
1050                 BufferedPacket p = con::makePacket(address, reliable,
1051                                 m_connection->GetProtocolID(), m_connection->GetPeerID(),
1052                                 c.channelnum);
1053
1054                 toadd.push(p);
1055         }
1056
1057         if (have_sequence_number) {
1058                 volatile u16 pcount = 0;
1059                 while (!toadd.empty()) {
1060                         BufferedPacket p = toadd.front();
1061                         toadd.pop();
1062 //                      LOG(dout_con<<connection->getDesc()
1063 //                                      << " queuing reliable packet for peer_id: " << c.peer_id
1064 //                                      << " channel: " << (c.channelnum&0xFF)
1065 //                                      << " seqnum: " << readU16(&p.data[BASE_HEADER_SIZE+1])
1066 //                                      << std::endl)
1067                         chan.queued_reliables.push(p);
1068                         pcount++;
1069                 }
1070                 sanity_check(chan.queued_reliables.size() < 0xFFFF);
1071                 return true;
1072         }
1073
1074         volatile u16 packets_available = toadd.size();
1075         /* we didn't get a single sequence number no need to fill queue */
1076         if (!have_initial_sequence_number) {
1077                 return false;
1078         }
1079
1080         while (!toadd.empty()) {
1081                 /* remove packet */
1082                 toadd.pop();
1083
1084                 bool successfully_put_back_sequence_number
1085                         = chan.putBackSequenceNumber(
1086                                 (initial_sequence_number+toadd.size() % (SEQNUM_MAX+1)));
1087
1088                 FATAL_ERROR_IF(!successfully_put_back_sequence_number, "error");
1089         }
1090
1091         // DO NOT REMOVE n_queued! It avoids a deadlock of async locked
1092         // 'log_message_mutex' and 'm_list_mutex'.
1093         u32 n_queued = chan.outgoing_reliables_sent.size();
1094
1095         LOG(dout_con<<m_connection->getDesc()
1096                         << " Windowsize exceeded on reliable sending "
1097                         << c.data.getSize() << " bytes"
1098                         << std::endl << "\t\tinitial_sequence_number: "
1099                         << initial_sequence_number
1100                         << std::endl << "\t\tgot at most            : "
1101                         << packets_available << " packets"
1102                         << std::endl << "\t\tpackets queued         : "
1103                         << n_queued
1104                         << std::endl);
1105
1106         return false;
1107 }
1108
1109 void UDPPeer::RunCommandQueues(
1110                                                         unsigned int max_packet_size,
1111                                                         unsigned int maxcommands,
1112                                                         unsigned int maxtransfer)
1113 {
1114
1115         for (Channel &channel : channels) {
1116                 unsigned int commands_processed = 0;
1117
1118                 if ((!channel.queued_commands.empty()) &&
1119                                 (channel.queued_reliables.size() < maxtransfer) &&
1120                                 (commands_processed < maxcommands)) {
1121                         try {
1122                                 ConnectionCommand c = channel.queued_commands.front();
1123
1124                                 LOG(dout_con << m_connection->getDesc()
1125                                                 << " processing queued reliable command " << std::endl);
1126
1127                                 // Packet is processed, remove it from queue
1128                                 if (processReliableSendCommand(c,max_packet_size)) {
1129                                         channel.queued_commands.pop_front();
1130                                 } else {
1131                                         LOG(dout_con << m_connection->getDesc()
1132                                                         << " Failed to queue packets for peer_id: " << c.peer_id
1133                                                         << ", delaying sending of " << c.data.getSize()
1134                                                         << " bytes" << std::endl);
1135                                 }
1136                         }
1137                         catch (ItemNotFoundException &e) {
1138                                 // intentionally empty
1139                         }
1140                 }
1141         }
1142 }
1143
1144 u16 UDPPeer::getNextSplitSequenceNumber(u8 channel)
1145 {
1146         assert(channel < CHANNEL_COUNT); // Pre-condition
1147         return channels[channel].readNextSplitSeqNum();
1148 }
1149
1150 void UDPPeer::setNextSplitSequenceNumber(u8 channel, u16 seqnum)
1151 {
1152         assert(channel < CHANNEL_COUNT); // Pre-condition
1153         channels[channel].setNextSplitSeqNum(seqnum);
1154 }
1155
1156 SharedBuffer<u8> UDPPeer::addSplitPacket(u8 channel, const BufferedPacket &toadd,
1157         bool reliable)
1158 {
1159         assert(channel < CHANNEL_COUNT); // Pre-condition
1160         return channels[channel].incoming_splits.insert(toadd, reliable);
1161 }
1162
1163 /*
1164         Connection
1165 */
1166
1167 Connection::Connection(u32 protocol_id, u32 max_packet_size, float timeout,
1168                 bool ipv6, PeerHandler *peerhandler) :
1169         m_udpSocket(ipv6),
1170         m_protocol_id(protocol_id),
1171         m_sendThread(new ConnectionSendThread(max_packet_size, timeout)),
1172         m_receiveThread(new ConnectionReceiveThread(max_packet_size)),
1173         m_bc_peerhandler(peerhandler)
1174
1175 {
1176         m_udpSocket.setTimeoutMs(5);
1177
1178         m_sendThread->setParent(this);
1179         m_receiveThread->setParent(this);
1180
1181         m_sendThread->start();
1182         m_receiveThread->start();
1183 }
1184
1185
1186 Connection::~Connection()
1187 {
1188         m_shutting_down = true;
1189         // request threads to stop
1190         m_sendThread->stop();
1191         m_receiveThread->stop();
1192
1193         //TODO for some unkonwn reason send/receive threads do not exit as they're
1194         // supposed to be but wait on peer timeout. To speed up shutdown we reduce
1195         // timeout to half a second.
1196         m_sendThread->setPeerTimeout(0.5);
1197
1198         // wait for threads to finish
1199         m_sendThread->wait();
1200         m_receiveThread->wait();
1201
1202         // Delete peers
1203         for (auto &peer : m_peers) {
1204                 delete peer.second;
1205         }
1206 }
1207
1208 /* Internal stuff */
1209 void Connection::putEvent(ConnectionEvent &e)
1210 {
1211         assert(e.type != CONNEVENT_NONE); // Pre-condition
1212         m_event_queue.push_back(e);
1213 }
1214
1215 void Connection::TriggerSend()
1216 {
1217         m_sendThread->Trigger();
1218 }
1219
1220 PeerHelper Connection::getPeerNoEx(session_t peer_id)
1221 {
1222         MutexAutoLock peerlock(m_peers_mutex);
1223         std::map<session_t, Peer *>::iterator node = m_peers.find(peer_id);
1224
1225         if (node == m_peers.end()) {
1226                 return PeerHelper(NULL);
1227         }
1228
1229         // Error checking
1230         FATAL_ERROR_IF(node->second->id != peer_id, "Invalid peer id");
1231
1232         return PeerHelper(node->second);
1233 }
1234
1235 /* find peer_id for address */
1236 u16 Connection::lookupPeer(Address& sender)
1237 {
1238         MutexAutoLock peerlock(m_peers_mutex);
1239         std::map<u16, Peer*>::iterator j;
1240         j = m_peers.begin();
1241         for(; j != m_peers.end(); ++j)
1242         {
1243                 Peer *peer = j->second;
1244                 if (peer->isPendingDeletion())
1245                         continue;
1246
1247                 Address tocheck;
1248
1249                 if ((peer->getAddress(MTP_MINETEST_RELIABLE_UDP, tocheck)) && (tocheck == sender))
1250                         return peer->id;
1251
1252                 if ((peer->getAddress(MTP_UDP, tocheck)) && (tocheck == sender))
1253                         return peer->id;
1254         }
1255
1256         return PEER_ID_INEXISTENT;
1257 }
1258
1259 bool Connection::deletePeer(session_t peer_id, bool timeout)
1260 {
1261         Peer *peer = 0;
1262
1263         /* lock list as short as possible */
1264         {
1265                 MutexAutoLock peerlock(m_peers_mutex);
1266                 if (m_peers.find(peer_id) == m_peers.end())
1267                         return false;
1268                 peer = m_peers[peer_id];
1269                 m_peers.erase(peer_id);
1270                 m_peer_ids.remove(peer_id);
1271         }
1272
1273         Address peer_address;
1274         //any peer has a primary address this never fails!
1275         peer->getAddress(MTP_PRIMARY, peer_address);
1276         // Create event
1277         ConnectionEvent e;
1278         e.peerRemoved(peer_id, timeout, peer_address);
1279         putEvent(e);
1280
1281
1282         peer->Drop();
1283         return true;
1284 }
1285
1286 /* Interface */
1287
1288 ConnectionEvent Connection::waitEvent(u32 timeout_ms)
1289 {
1290         try {
1291                 return m_event_queue.pop_front(timeout_ms);
1292         } catch(ItemNotFoundException &ex) {
1293                 ConnectionEvent e;
1294                 e.type = CONNEVENT_NONE;
1295                 return e;
1296         }
1297 }
1298
1299 void Connection::putCommand(ConnectionCommand &c)
1300 {
1301         if (!m_shutting_down) {
1302                 m_command_queue.push_back(c);
1303                 m_sendThread->Trigger();
1304         }
1305 }
1306
1307 void Connection::Serve(Address bind_addr)
1308 {
1309         ConnectionCommand c;
1310         c.serve(bind_addr);
1311         putCommand(c);
1312 }
1313
1314 void Connection::Connect(Address address)
1315 {
1316         ConnectionCommand c;
1317         c.connect(address);
1318         putCommand(c);
1319 }
1320
1321 bool Connection::Connected()
1322 {
1323         MutexAutoLock peerlock(m_peers_mutex);
1324
1325         if (m_peers.size() != 1)
1326                 return false;
1327
1328         std::map<session_t, Peer *>::iterator node = m_peers.find(PEER_ID_SERVER);
1329         if (node == m_peers.end())
1330                 return false;
1331
1332         if (m_peer_id == PEER_ID_INEXISTENT)
1333                 return false;
1334
1335         return true;
1336 }
1337
1338 void Connection::Disconnect()
1339 {
1340         ConnectionCommand c;
1341         c.disconnect();
1342         putCommand(c);
1343 }
1344
1345 bool Connection::Receive(NetworkPacket *pkt, u32 timeout)
1346 {
1347         /*
1348                 Note that this function can potentially wait infinitely if non-data
1349                 events keep happening before the timeout expires.
1350                 This is not considered to be a problem (is it?)
1351         */
1352         for(;;) {
1353                 ConnectionEvent e = waitEvent(timeout);
1354                 if (e.type != CONNEVENT_NONE)
1355                         LOG(dout_con << getDesc() << ": Receive: got event: "
1356                                         << e.describe() << std::endl);
1357                 switch(e.type) {
1358                 case CONNEVENT_NONE:
1359                         return false;
1360                 case CONNEVENT_DATA_RECEIVED:
1361                         // Data size is lesser than command size, ignoring packet
1362                         if (e.data.getSize() < 2) {
1363                                 continue;
1364                         }
1365
1366                         pkt->putRawPacket(*e.data, e.data.getSize(), e.peer_id);
1367                         return true;
1368                 case CONNEVENT_PEER_ADDED: {
1369                         UDPPeer tmp(e.peer_id, e.address, this);
1370                         if (m_bc_peerhandler)
1371                                 m_bc_peerhandler->peerAdded(&tmp);
1372                         continue;
1373                 }
1374                 case CONNEVENT_PEER_REMOVED: {
1375                         UDPPeer tmp(e.peer_id, e.address, this);
1376                         if (m_bc_peerhandler)
1377                                 m_bc_peerhandler->deletingPeer(&tmp, e.timeout);
1378                         continue;
1379                 }
1380                 case CONNEVENT_BIND_FAILED:
1381                         throw ConnectionBindFailed("Failed to bind socket "
1382                                         "(port already in use?)");
1383                 }
1384         }
1385         return false;
1386 }
1387
1388 void Connection::Receive(NetworkPacket *pkt)
1389 {
1390         bool any = Receive(pkt, m_bc_receive_timeout);
1391         if (!any)
1392                 throw NoIncomingDataException("No incoming data");
1393 }
1394
1395 bool Connection::TryReceive(NetworkPacket *pkt)
1396 {
1397         return Receive(pkt, 0);
1398 }
1399
1400 void Connection::Send(session_t peer_id, u8 channelnum,
1401                 NetworkPacket *pkt, bool reliable)
1402 {
1403         assert(channelnum < CHANNEL_COUNT); // Pre-condition
1404
1405         ConnectionCommand c;
1406
1407         c.send(peer_id, channelnum, pkt, reliable);
1408         putCommand(c);
1409 }
1410
1411 Address Connection::GetPeerAddress(session_t peer_id)
1412 {
1413         PeerHelper peer = getPeerNoEx(peer_id);
1414
1415         if (!peer)
1416                 throw PeerNotFoundException("No address for peer found!");
1417         Address peer_address;
1418         peer->getAddress(MTP_PRIMARY, peer_address);
1419         return peer_address;
1420 }
1421
1422 float Connection::getPeerStat(session_t peer_id, rtt_stat_type type)
1423 {
1424         PeerHelper peer = getPeerNoEx(peer_id);
1425         if (!peer) return -1;
1426         return peer->getStat(type);
1427 }
1428
1429 float Connection::getLocalStat(rate_stat_type type)
1430 {
1431         PeerHelper peer = getPeerNoEx(PEER_ID_SERVER);
1432
1433         FATAL_ERROR_IF(!peer, "Connection::getLocalStat we couldn't get our own peer? are you serious???");
1434
1435         float retval = 0.0;
1436
1437         for (Channel &channel : dynamic_cast<UDPPeer *>(&peer)->channels) {
1438                 switch(type) {
1439                         case CUR_DL_RATE:
1440                                 retval += channel.getCurrentDownloadRateKB();
1441                                 break;
1442                         case AVG_DL_RATE:
1443                                 retval += channel.getAvgDownloadRateKB();
1444                                 break;
1445                         case CUR_INC_RATE:
1446                                 retval += channel.getCurrentIncomingRateKB();
1447                                 break;
1448                         case AVG_INC_RATE:
1449                                 retval += channel.getAvgIncomingRateKB();
1450                                 break;
1451                         case AVG_LOSS_RATE:
1452                                 retval += channel.getAvgLossRateKB();
1453                                 break;
1454                         case CUR_LOSS_RATE:
1455                                 retval += channel.getCurrentLossRateKB();
1456                                 break;
1457                 default:
1458                         FATAL_ERROR("Connection::getLocalStat Invalid stat type");
1459                 }
1460         }
1461         return retval;
1462 }
1463
1464 u16 Connection::createPeer(Address& sender, MTProtocols protocol, int fd)
1465 {
1466         // Somebody wants to make a new connection
1467
1468         // Get a unique peer id (2 or higher)
1469         session_t peer_id_new = m_next_remote_peer_id;
1470         u16 overflow =  MAX_UDP_PEERS;
1471
1472         /*
1473                 Find an unused peer id
1474         */
1475         MutexAutoLock lock(m_peers_mutex);
1476         bool out_of_ids = false;
1477         for(;;) {
1478                 // Check if exists
1479                 if (m_peers.find(peer_id_new) == m_peers.end())
1480
1481                         break;
1482                 // Check for overflow
1483                 if (peer_id_new == overflow) {
1484                         out_of_ids = true;
1485                         break;
1486                 }
1487                 peer_id_new++;
1488         }
1489
1490         if (out_of_ids) {
1491                 errorstream << getDesc() << " ran out of peer ids" << std::endl;
1492                 return PEER_ID_INEXISTENT;
1493         }
1494
1495         // Create a peer
1496         Peer *peer = 0;
1497         peer = new UDPPeer(peer_id_new, sender, this);
1498
1499         m_peers[peer->id] = peer;
1500         m_peer_ids.push_back(peer->id);
1501
1502         m_next_remote_peer_id = (peer_id_new +1 ) % MAX_UDP_PEERS;
1503
1504         LOG(dout_con << getDesc()
1505                         << "createPeer(): giving peer_id=" << peer_id_new << std::endl);
1506
1507         ConnectionCommand cmd;
1508         SharedBuffer<u8> reply(4);
1509         writeU8(&reply[0], PACKET_TYPE_CONTROL);
1510         writeU8(&reply[1], CONTROLTYPE_SET_PEER_ID);
1511         writeU16(&reply[2], peer_id_new);
1512         cmd.createPeer(peer_id_new,reply);
1513         putCommand(cmd);
1514
1515         // Create peer addition event
1516         ConnectionEvent e;
1517         e.peerAdded(peer_id_new, sender);
1518         putEvent(e);
1519
1520         // We're now talking to a valid peer_id
1521         return peer_id_new;
1522 }
1523
1524 void Connection::PrintInfo(std::ostream &out)
1525 {
1526         m_info_mutex.lock();
1527         out<<getDesc()<<": ";
1528         m_info_mutex.unlock();
1529 }
1530
1531 const std::string Connection::getDesc()
1532 {
1533         return std::string("con(")+
1534                         itos(m_udpSocket.GetHandle())+"/"+itos(m_peer_id)+")";
1535 }
1536
1537 void Connection::DisconnectPeer(session_t peer_id)
1538 {
1539         ConnectionCommand discon;
1540         discon.disconnect_peer(peer_id);
1541         putCommand(discon);
1542 }
1543
1544 void Connection::sendAck(session_t peer_id, u8 channelnum, u16 seqnum)
1545 {
1546         assert(channelnum < CHANNEL_COUNT); // Pre-condition
1547
1548         LOG(dout_con<<getDesc()
1549                         <<" Queuing ACK command to peer_id: " << peer_id <<
1550                         " channel: " << (channelnum & 0xFF) <<
1551                         " seqnum: " << seqnum << std::endl);
1552
1553         ConnectionCommand c;
1554         SharedBuffer<u8> ack(4);
1555         writeU8(&ack[0], PACKET_TYPE_CONTROL);
1556         writeU8(&ack[1], CONTROLTYPE_ACK);
1557         writeU16(&ack[2], seqnum);
1558
1559         c.ack(peer_id, channelnum, ack);
1560         putCommand(c);
1561         m_sendThread->Trigger();
1562 }
1563
1564 UDPPeer* Connection::createServerPeer(Address& address)
1565 {
1566         if (getPeerNoEx(PEER_ID_SERVER) != 0)
1567         {
1568                 throw ConnectionException("Already connected to a server");
1569         }
1570
1571         UDPPeer *peer = new UDPPeer(PEER_ID_SERVER, address, this);
1572
1573         {
1574                 MutexAutoLock lock(m_peers_mutex);
1575                 m_peers[peer->id] = peer;
1576                 m_peer_ids.push_back(peer->id);
1577         }
1578
1579         return peer;
1580 }
1581
1582 } // namespace