diff options
Diffstat (limited to 'tests/enet/protocol.c')
-rw-r--r-- | tests/enet/protocol.c | 1848 |
1 files changed, 1848 insertions, 0 deletions
diff --git a/tests/enet/protocol.c b/tests/enet/protocol.c new file mode 100644 index 00000000..6d4618c7 --- /dev/null +++ b/tests/enet/protocol.c @@ -0,0 +1,1848 @@ +/** + @file protocol.c + @brief ENet protocol functions +*/ +#include <stdio.h> +#include <string.h> +#define ENET_BUILDING_LIB 1 +#include "enet/utility.h" +#include "enet/time.h" +#include "enet/enet.h" + +static size_t commandSizes [ENET_PROTOCOL_COMMAND_COUNT] = +{ + 0, + sizeof (ENetProtocolAcknowledge), + sizeof (ENetProtocolConnect), + sizeof (ENetProtocolVerifyConnect), + sizeof (ENetProtocolDisconnect), + sizeof (ENetProtocolPing), + sizeof (ENetProtocolSendReliable), + sizeof (ENetProtocolSendUnreliable), + sizeof (ENetProtocolSendFragment), + sizeof (ENetProtocolSendUnsequenced), + sizeof (ENetProtocolBandwidthLimit), + sizeof (ENetProtocolThrottleConfigure), + sizeof (ENetProtocolSendFragment) +}; + +size_t +enet_protocol_command_size (enet_uint8 commandNumber) +{ + return commandSizes [commandNumber & ENET_PROTOCOL_COMMAND_MASK]; +} + +static int +enet_protocol_dispatch_incoming_commands (ENetHost * host, ENetEvent * event) +{ + while (! enet_list_empty (& host -> dispatchQueue)) + { + ENetPeer * peer = (ENetPeer *) enet_list_remove (enet_list_begin (& host -> dispatchQueue)); + + peer -> needsDispatch = 0; + + switch (peer -> state) + { + case ENET_PEER_STATE_CONNECTION_PENDING: + case ENET_PEER_STATE_CONNECTION_SUCCEEDED: + peer -> state = ENET_PEER_STATE_CONNECTED; + + event -> type = ENET_EVENT_TYPE_CONNECT; + event -> peer = peer; + event -> data = peer -> eventData; + + return 1; + + case ENET_PEER_STATE_ZOMBIE: + host -> recalculateBandwidthLimits = 1; + + event -> type = ENET_EVENT_TYPE_DISCONNECT; + event -> peer = peer; + event -> data = peer -> eventData; + + enet_peer_reset (peer); + + return 1; + + case ENET_PEER_STATE_CONNECTED: + if (enet_list_empty (& peer -> dispatchedCommands)) + continue; + + event -> packet = enet_peer_receive (peer, & event -> channelID); + if (event -> packet == NULL) + continue; + + event -> type = ENET_EVENT_TYPE_RECEIVE; + event -> peer = peer; + + if (! enet_list_empty (& peer -> dispatchedCommands)) + { + peer -> needsDispatch = 1; + + enet_list_insert (enet_list_end (& host -> dispatchQueue), & peer -> dispatchList); + } + + return 1; + } + } + + return 0; +} + +static void +enet_protocol_dispatch_state (ENetHost * host, ENetPeer * peer, ENetPeerState state) +{ + peer -> state = state; + + if (! peer -> needsDispatch) + { + enet_list_insert (enet_list_end (& host -> dispatchQueue), & peer -> dispatchList); + + peer -> needsDispatch = 1; + } +} + +static void +enet_protocol_notify_connect (ENetHost * host, ENetPeer * peer, ENetEvent * event) +{ + host -> recalculateBandwidthLimits = 1; + + if (event != NULL) + { + peer -> state = ENET_PEER_STATE_CONNECTED; + + event -> type = ENET_EVENT_TYPE_CONNECT; + event -> peer = peer; + event -> data = peer -> eventData; + } + else + enet_protocol_dispatch_state (host, peer, peer -> state == ENET_PEER_STATE_CONNECTING ? ENET_PEER_STATE_CONNECTION_SUCCEEDED : ENET_PEER_STATE_CONNECTION_PENDING); +} + +static void +enet_protocol_notify_disconnect (ENetHost * host, ENetPeer * peer, ENetEvent * event) +{ + if (peer -> state >= ENET_PEER_STATE_CONNECTION_PENDING) + host -> recalculateBandwidthLimits = 1; + + if (peer -> state != ENET_PEER_STATE_CONNECTING && peer -> state < ENET_PEER_STATE_CONNECTION_SUCCEEDED) + enet_peer_reset (peer); + else + if (event != NULL) + { + event -> type = ENET_EVENT_TYPE_DISCONNECT; + event -> peer = peer; + event -> data = 0; + + enet_peer_reset (peer); + } + else + { + peer -> eventData = 0; + + enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE); + } +} + +static void +enet_protocol_remove_sent_unreliable_commands (ENetPeer * peer) +{ + ENetOutgoingCommand * outgoingCommand; + + while (! enet_list_empty (& peer -> sentUnreliableCommands)) + { + outgoingCommand = (ENetOutgoingCommand *) enet_list_front (& peer -> sentUnreliableCommands); + + enet_list_remove (& outgoingCommand -> outgoingCommandList); + + if (outgoingCommand -> packet != NULL) + { + -- outgoingCommand -> packet -> referenceCount; + + if (outgoingCommand -> packet -> referenceCount == 0) + enet_packet_destroy (outgoingCommand -> packet); + } + + enet_free (outgoingCommand); + } +} + +static ENetProtocolCommand +enet_protocol_remove_sent_reliable_command (ENetPeer * peer, enet_uint16 reliableSequenceNumber, enet_uint8 channelID) +{ + ENetOutgoingCommand * outgoingCommand = NULL; + ENetListIterator currentCommand; + ENetProtocolCommand commandNumber; + int wasSent = 1; + + for (currentCommand = enet_list_begin (& peer -> sentReliableCommands); + currentCommand != enet_list_end (& peer -> sentReliableCommands); + currentCommand = enet_list_next (currentCommand)) + { + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + + if (outgoingCommand -> reliableSequenceNumber == reliableSequenceNumber && + outgoingCommand -> command.header.channelID == channelID) + break; + } + + if (currentCommand == enet_list_end (& peer -> sentReliableCommands)) + { + for (currentCommand = enet_list_begin (& peer -> outgoingReliableCommands); + currentCommand != enet_list_end (& peer -> outgoingReliableCommands); + currentCommand = enet_list_next (currentCommand)) + { + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + + if (outgoingCommand -> sendAttempts < 1) return ENET_PROTOCOL_COMMAND_NONE; + + if (outgoingCommand -> reliableSequenceNumber == reliableSequenceNumber && + outgoingCommand -> command.header.channelID == channelID) + break; + } + + if (currentCommand == enet_list_end (& peer -> outgoingReliableCommands)) + return ENET_PROTOCOL_COMMAND_NONE; + + wasSent = 0; + } + + if (channelID < peer -> channelCount) + { + ENetChannel * channel = & peer -> channels [channelID]; + enet_uint16 reliableWindow = reliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + if (channel -> reliableWindows [reliableWindow] > 0) + { + -- channel -> reliableWindows [reliableWindow]; + if (! channel -> reliableWindows [reliableWindow]) + channel -> usedReliableWindows &= ~ (1 << reliableWindow); + } + } + + commandNumber = (ENetProtocolCommand) (outgoingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK); + + enet_list_remove (& outgoingCommand -> outgoingCommandList); + + if (outgoingCommand -> packet != NULL) + { + if (wasSent) + peer -> reliableDataInTransit -= outgoingCommand -> fragmentLength; + + -- outgoingCommand -> packet -> referenceCount; + + if (outgoingCommand -> packet -> referenceCount == 0) + enet_packet_destroy (outgoingCommand -> packet); + } + + enet_free (outgoingCommand); + + if (enet_list_empty (& peer -> sentReliableCommands)) + return commandNumber; + + outgoingCommand = (ENetOutgoingCommand *) enet_list_front (& peer -> sentReliableCommands); + + peer -> nextTimeout = outgoingCommand -> sentTime + outgoingCommand -> roundTripTimeout; + + return commandNumber; +} + +static ENetPeer * +enet_protocol_handle_connect (ENetHost * host, ENetProtocolHeader * header, ENetProtocol * command) +{ + enet_uint8 incomingSessionID, outgoingSessionID; + enet_uint32 mtu, windowSize; + ENetChannel * channel; + size_t channelCount; + ENetPeer * currentPeer; + ENetProtocol verifyCommand; + + channelCount = ENET_NET_TO_HOST_32 (command -> connect.channelCount); + + if (channelCount < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT || + channelCount > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT) + return NULL; + + for (currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + if (currentPeer -> state != ENET_PEER_STATE_DISCONNECTED && + currentPeer -> address.host == host -> receivedAddress.host && + currentPeer -> address.port == host -> receivedAddress.port && + currentPeer -> connectID == command -> connect.connectID) + return NULL; + } + + for (currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + if (currentPeer -> state == ENET_PEER_STATE_DISCONNECTED) + break; + } + + if (currentPeer >= & host -> peers [host -> peerCount]) + return NULL; + + if (channelCount > host -> channelLimit) + channelCount = host -> channelLimit; + currentPeer -> channels = (ENetChannel *) enet_malloc (channelCount * sizeof (ENetChannel)); + if (currentPeer -> channels == NULL) + return NULL; + currentPeer -> channelCount = channelCount; + currentPeer -> state = ENET_PEER_STATE_ACKNOWLEDGING_CONNECT; + currentPeer -> connectID = command -> connect.connectID; + currentPeer -> address = host -> receivedAddress; + currentPeer -> outgoingPeerID = ENET_NET_TO_HOST_16 (command -> connect.outgoingPeerID); + currentPeer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.incomingBandwidth); + currentPeer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.outgoingBandwidth); + currentPeer -> packetThrottleInterval = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleInterval); + currentPeer -> packetThrottleAcceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleAcceleration); + currentPeer -> packetThrottleDeceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleDeceleration); + currentPeer -> eventData = ENET_NET_TO_HOST_32 (command -> connect.data); + + incomingSessionID = command -> connect.incomingSessionID == 0xFF ? currentPeer -> outgoingSessionID : command -> connect.incomingSessionID; + incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT); + if (incomingSessionID == currentPeer -> outgoingSessionID) + incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT); + currentPeer -> outgoingSessionID = incomingSessionID; + + outgoingSessionID = command -> connect.outgoingSessionID == 0xFF ? currentPeer -> incomingSessionID : command -> connect.outgoingSessionID; + outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT); + if (outgoingSessionID == currentPeer -> incomingSessionID) + outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT); + currentPeer -> incomingSessionID = outgoingSessionID; + + for (channel = currentPeer -> channels; + channel < & currentPeer -> channels [channelCount]; + ++ channel) + { + channel -> outgoingReliableSequenceNumber = 0; + channel -> outgoingUnreliableSequenceNumber = 0; + channel -> incomingReliableSequenceNumber = 0; + channel -> incomingUnreliableSequenceNumber = 0; + + enet_list_clear (& channel -> incomingReliableCommands); + enet_list_clear (& channel -> incomingUnreliableCommands); + + channel -> usedReliableWindows = 0; + memset (channel -> reliableWindows, 0, sizeof (channel -> reliableWindows)); + } + + mtu = ENET_NET_TO_HOST_32 (command -> connect.mtu); + + if (mtu < ENET_PROTOCOL_MINIMUM_MTU) + mtu = ENET_PROTOCOL_MINIMUM_MTU; + else + if (mtu > ENET_PROTOCOL_MAXIMUM_MTU) + mtu = ENET_PROTOCOL_MAXIMUM_MTU; + + currentPeer -> mtu = mtu; + + if (host -> outgoingBandwidth == 0 && + currentPeer -> incomingBandwidth == 0) + currentPeer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + else + if (host -> outgoingBandwidth == 0 || + currentPeer -> incomingBandwidth == 0) + currentPeer -> windowSize = (ENET_MAX (host -> outgoingBandwidth, currentPeer -> incomingBandwidth) / + ENET_PEER_WINDOW_SIZE_SCALE) * + ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + else + currentPeer -> windowSize = (ENET_MIN (host -> outgoingBandwidth, currentPeer -> incomingBandwidth) / + ENET_PEER_WINDOW_SIZE_SCALE) * + ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + + if (currentPeer -> windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE) + currentPeer -> windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + else + if (currentPeer -> windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE) + currentPeer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + + if (host -> incomingBandwidth == 0) + windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + else + windowSize = (host -> incomingBandwidth / ENET_PEER_WINDOW_SIZE_SCALE) * + ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + + if (windowSize > ENET_NET_TO_HOST_32 (command -> connect.windowSize)) + windowSize = ENET_NET_TO_HOST_32 (command -> connect.windowSize); + + if (windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE) + windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + else + if (windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE) + windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + + verifyCommand.header.command = ENET_PROTOCOL_COMMAND_VERIFY_CONNECT | ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE; + verifyCommand.header.channelID = 0xFF; + verifyCommand.verifyConnect.outgoingPeerID = ENET_HOST_TO_NET_16 (currentPeer -> incomingPeerID); + verifyCommand.verifyConnect.incomingSessionID = incomingSessionID; + verifyCommand.verifyConnect.outgoingSessionID = outgoingSessionID; + verifyCommand.verifyConnect.mtu = ENET_HOST_TO_NET_16 (currentPeer -> mtu); + verifyCommand.verifyConnect.windowSize = ENET_HOST_TO_NET_32 (windowSize); + verifyCommand.verifyConnect.channelCount = ENET_HOST_TO_NET_32 (channelCount); + verifyCommand.verifyConnect.incomingBandwidth = ENET_HOST_TO_NET_32 (host -> incomingBandwidth); + verifyCommand.verifyConnect.outgoingBandwidth = ENET_HOST_TO_NET_32 (host -> outgoingBandwidth); + verifyCommand.verifyConnect.packetThrottleInterval = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleInterval); + verifyCommand.verifyConnect.packetThrottleAcceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleAcceleration); + verifyCommand.verifyConnect.packetThrottleDeceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleDeceleration); + verifyCommand.verifyConnect.connectID = currentPeer -> connectID; + + enet_peer_queue_outgoing_command (currentPeer, & verifyCommand, NULL, 0, 0); + + return currentPeer; +} + +static int +enet_protocol_handle_send_reliable (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData) +{ + ENetPacket * packet; + size_t dataLength; + + if (command -> header.channelID >= peer -> channelCount || + (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)) + return -1; + + dataLength = ENET_NET_TO_HOST_16 (command -> sendReliable.dataLength); + * currentData += dataLength; + if (dataLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + * currentData < host -> receivedData || + * currentData > & host -> receivedData [host -> receivedDataLength]) + return -1; + + packet = enet_packet_create ((const enet_uint8 *) command + sizeof (ENetProtocolSendReliable), + dataLength, + ENET_PACKET_FLAG_RELIABLE); + if (packet == NULL || + enet_peer_queue_incoming_command (peer, command, packet, 0) == NULL) + return -1; + + return 0; +} + +static int +enet_protocol_handle_send_unsequenced (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData) +{ + ENetPacket * packet; + enet_uint32 unsequencedGroup, index; + size_t dataLength; + + if (command -> header.channelID >= peer -> channelCount || + (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)) + return -1; + + dataLength = ENET_NET_TO_HOST_16 (command -> sendUnsequenced.dataLength); + * currentData += dataLength; + if (dataLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + * currentData < host -> receivedData || + * currentData > & host -> receivedData [host -> receivedDataLength]) + return -1; + + unsequencedGroup = ENET_NET_TO_HOST_16 (command -> sendUnsequenced.unsequencedGroup); + index = unsequencedGroup % ENET_PEER_UNSEQUENCED_WINDOW_SIZE; + + if (unsequencedGroup < peer -> incomingUnsequencedGroup) + unsequencedGroup += 0x10000; + + if (unsequencedGroup >= (enet_uint32) peer -> incomingUnsequencedGroup + ENET_PEER_FREE_UNSEQUENCED_WINDOWS * ENET_PEER_UNSEQUENCED_WINDOW_SIZE) + return 0; + + unsequencedGroup &= 0xFFFF; + + if (unsequencedGroup - index != peer -> incomingUnsequencedGroup) + { + peer -> incomingUnsequencedGroup = unsequencedGroup - index; + + memset (peer -> unsequencedWindow, 0, sizeof (peer -> unsequencedWindow)); + } + else + if (peer -> unsequencedWindow [index / 32] & (1 << (index % 32))) + return 0; + + packet = enet_packet_create ((const enet_uint8 *) command + sizeof (ENetProtocolSendUnsequenced), + dataLength, + ENET_PACKET_FLAG_UNSEQUENCED); + if (packet == NULL || + enet_peer_queue_incoming_command (peer, command, packet, 0) == NULL) + return -1; + + peer -> unsequencedWindow [index / 32] |= 1 << (index % 32); + + return 0; +} + +static int +enet_protocol_handle_send_unreliable (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData) +{ + ENetPacket * packet; + size_t dataLength; + + if (command -> header.channelID >= peer -> channelCount || + (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)) + return -1; + + dataLength = ENET_NET_TO_HOST_16 (command -> sendUnreliable.dataLength); + * currentData += dataLength; + if (dataLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + * currentData < host -> receivedData || + * currentData > & host -> receivedData [host -> receivedDataLength]) + return -1; + + packet = enet_packet_create ((const enet_uint8 *) command + sizeof (ENetProtocolSendUnreliable), + dataLength, + 0); + if (packet == NULL || + enet_peer_queue_incoming_command (peer, command, packet, 0) == NULL) + return -1; + + return 0; +} + +static int +enet_protocol_handle_send_fragment (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData) +{ + enet_uint32 fragmentNumber, + fragmentCount, + fragmentOffset, + fragmentLength, + startSequenceNumber, + totalLength; + ENetChannel * channel; + enet_uint16 startWindow, currentWindow; + ENetListIterator currentCommand; + ENetIncomingCommand * startCommand = NULL; + + if (command -> header.channelID >= peer -> channelCount || + (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)) + return -1; + + fragmentLength = ENET_NET_TO_HOST_16 (command -> sendFragment.dataLength); + * currentData += fragmentLength; + if (fragmentLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + * currentData < host -> receivedData || + * currentData > & host -> receivedData [host -> receivedDataLength]) + return -1; + + channel = & peer -> channels [command -> header.channelID]; + startSequenceNumber = ENET_NET_TO_HOST_16 (command -> sendFragment.startSequenceNumber); + startWindow = startSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + currentWindow = channel -> incomingReliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + + if (startSequenceNumber < channel -> incomingReliableSequenceNumber) + startWindow += ENET_PEER_RELIABLE_WINDOWS; + + if (startWindow < currentWindow || startWindow >= currentWindow + ENET_PEER_FREE_RELIABLE_WINDOWS - 1) + return 0; + + fragmentNumber = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentNumber); + fragmentCount = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentCount); + fragmentOffset = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentOffset); + totalLength = ENET_NET_TO_HOST_32 (command -> sendFragment.totalLength); + + if (fragmentCount > ENET_PROTOCOL_MAXIMUM_FRAGMENT_COUNT || + fragmentNumber >= fragmentCount || + totalLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + fragmentOffset >= totalLength || + fragmentLength > totalLength - fragmentOffset) + return -1; + + for (currentCommand = enet_list_previous (enet_list_end (& channel -> incomingReliableCommands)); + currentCommand != enet_list_end (& channel -> incomingReliableCommands); + currentCommand = enet_list_previous (currentCommand)) + { + ENetIncomingCommand * incomingCommand = (ENetIncomingCommand *) currentCommand; + + if (startSequenceNumber >= channel -> incomingReliableSequenceNumber) + { + if (incomingCommand -> reliableSequenceNumber < channel -> incomingReliableSequenceNumber) + continue; + } + else + if (incomingCommand -> reliableSequenceNumber >= channel -> incomingReliableSequenceNumber) + break; + + if (incomingCommand -> reliableSequenceNumber <= startSequenceNumber) + { + if (incomingCommand -> reliableSequenceNumber < startSequenceNumber) + break; + + if ((incomingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK) != ENET_PROTOCOL_COMMAND_SEND_FRAGMENT || + totalLength != incomingCommand -> packet -> dataLength || + fragmentCount != incomingCommand -> fragmentCount) + return -1; + + startCommand = incomingCommand; + break; + } + } + + if (startCommand == NULL) + { + ENetProtocol hostCommand = * command; + ENetPacket * packet = enet_packet_create (NULL, totalLength, ENET_PACKET_FLAG_RELIABLE); + if (packet == NULL) + return -1; + + hostCommand.header.reliableSequenceNumber = startSequenceNumber; + + startCommand = enet_peer_queue_incoming_command (peer, & hostCommand, packet, fragmentCount); + if (startCommand == NULL) + return -1; + } + + if ((startCommand -> fragments [fragmentNumber / 32] & (1 << (fragmentNumber % 32))) == 0) + { + -- startCommand -> fragmentsRemaining; + + startCommand -> fragments [fragmentNumber / 32] |= (1 << (fragmentNumber % 32)); + + if (fragmentOffset + fragmentLength > startCommand -> packet -> dataLength) + fragmentLength = startCommand -> packet -> dataLength - fragmentOffset; + + memcpy (startCommand -> packet -> data + fragmentOffset, + (enet_uint8 *) command + sizeof (ENetProtocolSendFragment), + fragmentLength); + + if (startCommand -> fragmentsRemaining <= 0) + enet_peer_dispatch_incoming_reliable_commands (peer, channel); + } + + return 0; +} + +static int +enet_protocol_handle_send_unreliable_fragment (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData) +{ + enet_uint32 fragmentNumber, + fragmentCount, + fragmentOffset, + fragmentLength, + reliableSequenceNumber, + startSequenceNumber, + totalLength; + enet_uint16 reliableWindow, currentWindow; + ENetChannel * channel; + ENetListIterator currentCommand; + ENetIncomingCommand * startCommand = NULL; + + if (command -> header.channelID >= peer -> channelCount || + (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)) + return -1; + + fragmentLength = ENET_NET_TO_HOST_16 (command -> sendFragment.dataLength); + * currentData += fragmentLength; + if (fragmentLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + * currentData < host -> receivedData || + * currentData > & host -> receivedData [host -> receivedDataLength]) + return -1; + + channel = & peer -> channels [command -> header.channelID]; + reliableSequenceNumber = command -> header.reliableSequenceNumber; + startSequenceNumber = ENET_NET_TO_HOST_16 (command -> sendFragment.startSequenceNumber); + + reliableWindow = reliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + currentWindow = channel -> incomingReliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + + if (reliableSequenceNumber < channel -> incomingReliableSequenceNumber) + reliableWindow += ENET_PEER_RELIABLE_WINDOWS; + + if (reliableWindow < currentWindow || reliableWindow >= currentWindow + ENET_PEER_FREE_RELIABLE_WINDOWS - 1) + return 0; + + if (reliableSequenceNumber == channel -> incomingReliableSequenceNumber && + startSequenceNumber <= channel -> incomingUnreliableSequenceNumber) + return 0; + + fragmentNumber = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentNumber); + fragmentCount = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentCount); + fragmentOffset = ENET_NET_TO_HOST_32 (command -> sendFragment.fragmentOffset); + totalLength = ENET_NET_TO_HOST_32 (command -> sendFragment.totalLength); + + if (fragmentCount > ENET_PROTOCOL_MAXIMUM_FRAGMENT_COUNT || + fragmentNumber >= fragmentCount || + totalLength > ENET_PROTOCOL_MAXIMUM_PACKET_SIZE || + fragmentOffset >= totalLength || + fragmentLength > totalLength - fragmentOffset) + return -1; + + for (currentCommand = enet_list_previous (enet_list_end (& channel -> incomingUnreliableCommands)); + currentCommand != enet_list_end (& channel -> incomingUnreliableCommands); + currentCommand = enet_list_previous (currentCommand)) + { + ENetIncomingCommand * incomingCommand = (ENetIncomingCommand *) currentCommand; + + if (reliableSequenceNumber >= channel -> incomingReliableSequenceNumber) + { + if (incomingCommand -> reliableSequenceNumber < channel -> incomingReliableSequenceNumber) + continue; + } + else + if (incomingCommand -> reliableSequenceNumber >= channel -> incomingReliableSequenceNumber) + break; + + if (incomingCommand -> reliableSequenceNumber < reliableSequenceNumber) + break; + + if (incomingCommand -> reliableSequenceNumber > reliableSequenceNumber) + continue; + + if (incomingCommand -> unreliableSequenceNumber <= startSequenceNumber) + { + if (incomingCommand -> unreliableSequenceNumber < startSequenceNumber) + break; + + if ((incomingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK) != ENET_PROTOCOL_COMMAND_SEND_UNRELIABLE_FRAGMENT || + totalLength != incomingCommand -> packet -> dataLength || + fragmentCount != incomingCommand -> fragmentCount) + return -1; + + startCommand = incomingCommand; + break; + } + } + + if (startCommand == NULL) + { + ENetPacket * packet = enet_packet_create (NULL, totalLength, ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT); + if (packet == NULL) + return -1; + + startCommand = enet_peer_queue_incoming_command (peer, command, packet, fragmentCount); + if (startCommand == NULL) + return -1; + } + + if ((startCommand -> fragments [fragmentNumber / 32] & (1 << (fragmentNumber % 32))) == 0) + { + -- startCommand -> fragmentsRemaining; + + startCommand -> fragments [fragmentNumber / 32] |= (1 << (fragmentNumber % 32)); + + if (fragmentOffset + fragmentLength > startCommand -> packet -> dataLength) + fragmentLength = startCommand -> packet -> dataLength - fragmentOffset; + + memcpy (startCommand -> packet -> data + fragmentOffset, + (enet_uint8 *) command + sizeof (ENetProtocolSendFragment), + fragmentLength); + + if (startCommand -> fragmentsRemaining <= 0) + enet_peer_dispatch_incoming_unreliable_commands (peer, channel); + } + + return 0; +} + +static int +enet_protocol_handle_ping (ENetHost * host, ENetPeer * peer, const ENetProtocol * command) +{ + return 0; +} + +static int +enet_protocol_handle_bandwidth_limit (ENetHost * host, ENetPeer * peer, const ENetProtocol * command) +{ + peer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> bandwidthLimit.incomingBandwidth); + peer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> bandwidthLimit.outgoingBandwidth); + + if (peer -> incomingBandwidth == 0 && host -> outgoingBandwidth == 0) + peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + else + peer -> windowSize = (ENET_MIN (peer -> incomingBandwidth, host -> outgoingBandwidth) / + ENET_PEER_WINDOW_SIZE_SCALE) * ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + + if (peer -> windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE) + peer -> windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + else + if (peer -> windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE) + peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + + return 0; +} + +static int +enet_protocol_handle_throttle_configure (ENetHost * host, ENetPeer * peer, const ENetProtocol * command) +{ + peer -> packetThrottleInterval = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleInterval); + peer -> packetThrottleAcceleration = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleAcceleration); + peer -> packetThrottleDeceleration = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleDeceleration); + + return 0; +} + +static int +enet_protocol_handle_disconnect (ENetHost * host, ENetPeer * peer, const ENetProtocol * command) +{ + if (peer -> state == ENET_PEER_STATE_ZOMBIE || peer -> state == ENET_PEER_STATE_ACKNOWLEDGING_DISCONNECT) + return 0; + + enet_peer_reset_queues (peer); + + if (peer -> state == ENET_PEER_STATE_CONNECTION_SUCCEEDED || peer -> state == ENET_PEER_STATE_DISCONNECTING) + enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE); + else + if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) + { + if (peer -> state == ENET_PEER_STATE_CONNECTION_PENDING) host -> recalculateBandwidthLimits = 1; + + enet_peer_reset (peer); + } + else + if (command -> header.command & ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE) + peer -> state = ENET_PEER_STATE_ACKNOWLEDGING_DISCONNECT; + else + enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE); + + if (peer -> state != ENET_PEER_STATE_DISCONNECTED) + peer -> eventData = ENET_NET_TO_HOST_32 (command -> disconnect.data); + + return 0; +} + +static int +enet_protocol_handle_acknowledge (ENetHost * host, ENetEvent * event, ENetPeer * peer, const ENetProtocol * command) +{ + enet_uint32 roundTripTime, + receivedSentTime, + receivedReliableSequenceNumber; + ENetProtocolCommand commandNumber; + + receivedSentTime = ENET_NET_TO_HOST_16 (command -> acknowledge.receivedSentTime); + receivedSentTime |= host -> serviceTime & 0xFFFF0000; + if ((receivedSentTime & 0x8000) > (host -> serviceTime & 0x8000)) + receivedSentTime -= 0x10000; + + if (ENET_TIME_LESS (host -> serviceTime, receivedSentTime)) + return 0; + + peer -> lastReceiveTime = host -> serviceTime; + peer -> earliestTimeout = 0; + + roundTripTime = ENET_TIME_DIFFERENCE (host -> serviceTime, receivedSentTime); + + enet_peer_throttle (peer, roundTripTime); + + peer -> roundTripTimeVariance -= peer -> roundTripTimeVariance / 4; + + if (roundTripTime >= peer -> roundTripTime) + { + peer -> roundTripTime += (roundTripTime - peer -> roundTripTime) / 8; + peer -> roundTripTimeVariance += (roundTripTime - peer -> roundTripTime) / 4; + } + else + { + peer -> roundTripTime -= (peer -> roundTripTime - roundTripTime) / 8; + peer -> roundTripTimeVariance += (peer -> roundTripTime - roundTripTime) / 4; + } + + if (peer -> roundTripTime < peer -> lowestRoundTripTime) + peer -> lowestRoundTripTime = peer -> roundTripTime; + + if (peer -> roundTripTimeVariance > peer -> highestRoundTripTimeVariance) + peer -> highestRoundTripTimeVariance = peer -> roundTripTimeVariance; + + if (peer -> packetThrottleEpoch == 0 || + ENET_TIME_DIFFERENCE (host -> serviceTime, peer -> packetThrottleEpoch) >= peer -> packetThrottleInterval) + { + peer -> lastRoundTripTime = peer -> lowestRoundTripTime; + peer -> lastRoundTripTimeVariance = peer -> highestRoundTripTimeVariance; + peer -> lowestRoundTripTime = peer -> roundTripTime; + peer -> highestRoundTripTimeVariance = peer -> roundTripTimeVariance; + peer -> packetThrottleEpoch = host -> serviceTime; + } + + receivedReliableSequenceNumber = ENET_NET_TO_HOST_16 (command -> acknowledge.receivedReliableSequenceNumber); + + commandNumber = enet_protocol_remove_sent_reliable_command (peer, receivedReliableSequenceNumber, command -> header.channelID); + + switch (peer -> state) + { + case ENET_PEER_STATE_ACKNOWLEDGING_CONNECT: + if (commandNumber != ENET_PROTOCOL_COMMAND_VERIFY_CONNECT) + return -1; + + enet_protocol_notify_connect (host, peer, event); + break; + + case ENET_PEER_STATE_DISCONNECTING: + if (commandNumber != ENET_PROTOCOL_COMMAND_DISCONNECT) + return -1; + + enet_protocol_notify_disconnect (host, peer, event); + break; + + case ENET_PEER_STATE_DISCONNECT_LATER: + if (enet_list_empty (& peer -> outgoingReliableCommands) && + enet_list_empty (& peer -> outgoingUnreliableCommands) && + enet_list_empty (& peer -> sentReliableCommands)) + enet_peer_disconnect (peer, peer -> eventData); + break; + } + + return 0; +} + +static int +enet_protocol_handle_verify_connect (ENetHost * host, ENetEvent * event, ENetPeer * peer, const ENetProtocol * command) +{ + enet_uint32 mtu, windowSize; + size_t channelCount; + + if (peer -> state != ENET_PEER_STATE_CONNECTING) + return 0; + + channelCount = ENET_NET_TO_HOST_32 (command -> verifyConnect.channelCount); + + if (channelCount < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT || channelCount > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT || + ENET_NET_TO_HOST_32 (command -> verifyConnect.packetThrottleInterval) != peer -> packetThrottleInterval || + ENET_NET_TO_HOST_32 (command -> verifyConnect.packetThrottleAcceleration) != peer -> packetThrottleAcceleration || + ENET_NET_TO_HOST_32 (command -> verifyConnect.packetThrottleDeceleration) != peer -> packetThrottleDeceleration || + command -> verifyConnect.connectID != peer -> connectID) + { + peer -> eventData = 0; + + enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE); + + return -1; + } + + enet_protocol_remove_sent_reliable_command (peer, 1, 0xFF); + + if (channelCount < peer -> channelCount) + peer -> channelCount = channelCount; + + peer -> outgoingPeerID = ENET_NET_TO_HOST_16 (command -> verifyConnect.outgoingPeerID); + peer -> incomingSessionID = command -> verifyConnect.incomingSessionID; + peer -> outgoingSessionID = command -> verifyConnect.outgoingSessionID; + + mtu = ENET_NET_TO_HOST_32 (command -> verifyConnect.mtu); + + if (mtu < ENET_PROTOCOL_MINIMUM_MTU) + mtu = ENET_PROTOCOL_MINIMUM_MTU; + else + if (mtu > ENET_PROTOCOL_MAXIMUM_MTU) + mtu = ENET_PROTOCOL_MAXIMUM_MTU; + + if (mtu < peer -> mtu) + peer -> mtu = mtu; + + windowSize = ENET_NET_TO_HOST_32 (command -> verifyConnect.windowSize); + + if (windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE) + windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE; + + if (windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE) + windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + + if (windowSiz |