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* Sapier's fix for the RESEND RELIABLE problem (#4170)Robert Kiraly2016-06-03
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* Tolerate packet reordering in the early init processest312016-05-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes a bug where packet reordering made the server give the client two peer ids instead of one. This in turn confused reliable packet sending and made connecting to the server fail. The client usually sends three packets at init: one "dummy" packet consisting of two 0 bytes, and the init packet as well as its legacy counterpart. The last one can be turned off since commit af30183124d40a969040d7de4b3a487feec466e4, but this is of lower relevance for the bug. The relevant part here is that network packet reorder (which is a normal occurence) can make the packets reach the server in different order. If reorder puts the dummy packet further behind, the following would happen before the patch: 1. The server will get one of the init packets on channel 1 and assign the client a peer id, as the packet will have zero as peer id. 2. The server sends a CONTROLTYPE_SET_PEER_ID packet to inform the client of the peer id. 3. The next packet from the client will contain the peer id set by the server. 4. The server sets the m_has_sent_with_id member for the client's peer structure to true. 5. Now the dummy packet arrives. It has a peer id of zero, therefore the server searches whether it already has a peer id for the address the packet was sent from. The search fails because m_has_sent_with_id was set to true and the server only searched for peers with m_has_sent_with_id set to false. 6. In a working setup, the server would assign the dummy packet to the correct peer id. However the server instead now assigns a second peer id and peer structure to the peer, and assign the packet to that new peer. 7. In order to inform the peer of its peer id, the server sends a CONTROLTYPE_SET_PEER_ID command packet, reliably, to the peer. This packet uses the new peer id. 8. The client sends an ack to that packet, not with the new peer id but with the peer id sent in 2. 9. This packet reaches the server, but it drops the ACK as the peer id does not map to any un-ACK-ed packets with that seqnum. The same time, the server still waits for an ACK with the new peer id, which of course won't come. This causes the server to periodically re-try sending that packet, and the client ACKing it each time. Steps 7-9 cause annoyances and erroneous output, but don't cause the connection failure itself. The actual mistake that causes the connection failure happens in 6: The server does not assign the dummy packet to the correct peer, but to a newly created one. Therefore, all further packets sent by the client on channel 0 are now buffered by the server as it waits for the dummy packet to reach the peer, which of course doesn't happen as the server assigned that packet to the second peer it created for the client. This makes the connection code indefinitely buffer the TOSERVER_CLIENT_READY packet, not passing it to higher level code, which stalls the continuation of the further init process indefinitely and causes the actual bug. Maybe this can be caused by reordered init packets as well, the only studied case was where network has reliably reordered the dummy packet to get sent after the init packets. The patch fixes the bug by not ignoring peers where m_has_sent_with_id has been set anymore. The other changes of the patch are just cleanups of unused methods and fields and additional explanatory comments. One could think of alternate ways to fix the bug: * The client could simply take the new peer id and continue communicating with that. This is however worse than the fix as it requires the peer id set command to be sent reliably (which currently happens, but it cant be changed anymore). Also, such a change would require both server and client to be patched in order for the bug to be fixed, as right now the client ignores peer id set commands after the peer id is different from PEER_ID_INEXISTENT and the server requires modification too to change the peer id internally. And, most importantly, right now we guarantee higher level server code that the peer id for a certain peer does not change. This guarantee would have to be broken, and it would require much larger changes to the server than this patch means. * One could stop sending the dummy packet. One may be unsure whether this is a good idea, as the meaning of the dummy packet is not known (it might be there for something important), and as it is possible that the init packets may cause this problem as well (although it may be possible too that they can't cause this). Thanks to @auouymous who had originally reported this bug and who has helped patiently in finding its cause.
* Always use errorstream for DEBUG_EXCEPTION_HANDLERShadowNinja2015-10-14
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* Use warningstream for log messages with WARNINGShadowNinja2015-10-14
| | | | Remove DTIME macro and its uses, too
* Change i++ to ++iDavid Jones2015-08-25
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* Clean up threadingShadowNinja2015-08-23
| | | | | | | | | | | | | | | | | | | | * Rename everything. * Strip J prefix. * Change UpperCamelCase functions to lowerCamelCase. * Remove global (!) semaphore count mutex on OSX. * Remove semaphore count getter (unused, unsafe, depended on internal API functions on Windows, and used a hack on OSX). * Add `Atomic<type>`. * Make `Thread` handle thread names. * Add support for C++11 multi-threading. * Combine pthread and win32 sources. * Remove `ThreadStarted` (unused, unneeded). * Move some includes from the headers to the sources. * Move all of `Event` into its header (allows inlining with no new includes). * Make `Event` use `Semaphore` (except on Windows). * Move some porting functions into `Thread`. * Integrate logging with `Thread`. * Add threading test.
* Remove unused function from connection.{cpp,h}nerzhul2015-08-15
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* connection: Make assertions non-fatal for received datakwolekr2015-08-05
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* connection.cpp: remove unused constructorLoic Blot2015-07-14
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* Move globals from main.cpp to more sane locationsCraig Robbins2015-04-01
| | | | | | | | | | | | Move debug streams to log.cpp|h Move GUI-related globals to clientlauncher Move g_settings and g_settings_path to settings.cpp|h Move g_menuclouds to clouds.cpp|h Move g_profiler to profiler.cpp|h
* Connection::Receive(): receive Network Packet instead of SharedBuffer<u8>.Loic Blot2015-03-31
| | | | | | | Because we get a Buffer<u8> from ConnectionEvent, don't convert it to SharedBuffer<u8> and return it to Server/Client::Receive which will convert it to NetworkPacket Instead, put the Buffer<u8> directly to NetworkPacket and return it to packet processing This remove a long existing memory copy Also check the packet size directly into Connection::Receive instead of packet processing
* RunCommandQueues: little optimizationLoic Blot2015-03-31
| | | | remove command from queue on success, else do nothing, instead of remove command from queue and push it front on success
* Typo in getOutgoingSequenceNumber => successfull to successfulLoic Blot2015-03-31
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* queued_commands must be a std::deque. RunCommandQueues needs to push packet ↵Loic Blot2015-03-29
| | | | on front, not back
* Remove unused ConnectionCommand::sendToAll function. ↵Loic Blot2015-03-22
| | | | | | NetworkPacket::oldForgePacket returns Buffer instead of SharedBuffer and is used in ConnectionCommand instead of Connection::Send This remove the NetworkPacket buffer => SharedBuffer => Buffer copy. Now NetworkPacket => Buffer
* Replace NetworkPacket pointers to referencesLoic Blot2015-03-13
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* For usages of assert() that are meant to persist in Release builds (when ↵Craig Robbins2015-03-07
| | | | NDEBUG is defined), replace those usages with persistent alternatives
* Remove Queue class which uses std::list and use native std::queueLoic Blot2015-03-05
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* Fix some memory leaks on packet sending.Loic Blot2015-02-21
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* [Patch 2/4] Network rework: packet writing, sending and cleanupsLoic Blot2015-02-16
NetworkPacket.cpp: * Remove some deprecated functions, we must use streaming interface * m_data converted from u8* to std::vector<u8> * Add an exporter to forge packet to Connection object * implement operator << std::wstring. n * implement operator << std::string * dynamic resize when write packet content. * fix string writing and performances. * create ServerCommandFactory, used by client to get useful informations about packet processing (sending). * Reliability * Transmit channel * Implement putRawString for some ugly char (_INIT packet), and use it. * Many packet read and write migrated * Implement oldForgePacket to interface writing with current connection * fix U8/char/bool writing * fix string writing and performances. * add some missing functions * Use v3s16 read instead of reading x,y,z separately * Add irr::video::SColor support into packets * Add some missing handlers * Add a template function to increase offset * Throw a serialization error on packet reading (must be improved) PacketFactories: * Create ServerCommandFactory, used by client to get useful informations about packet processing (sending). * Create ClientCommandFactory, used by server to get useful informations about packet processing (sending). Client.cpp: * implement NetworkPacket ::Send interface. * Move packet handlers to a dedicated file * Remove Client::Send(SharedBuffer) Server.cpp: * implement NetworkPacket ::Send interface. * Rewrite all packets using NetworkPacket * Move packet handlers to a dedicated file * Remove Server::Send(SharedBuffer) ClientIface.cpp: * Remove sendToAll(SharedBuffer<u8>) Connection.hpp rework: * Remove duplicate include * Remove duplicate negation * Remove a useless variable * Improve code performance by using a m_peers_list instead of scanning m_peers map * Remove Connection::Send(SharedBuffer) * Fix useafterfree into NetworkPacket Sending * Remove unused Connection::sendToAll Test.cpp: * Remove dead code * Update tests to use NetworkPackets Misc: * add new wrappers to Send packets in client, using NetworkPacket * Add NetworkPacket methods for Connection * coding style fix * dead code since changes cleanup * Use v3s16 read instead of reading x,y,z separately in some packets * Use different files to handle packets received by client and server * Cleanup: Remove useless includes ok @Zeno- Tested by @Zeno- @VanessaE and @nerzhul on running servers