diff options
Diffstat (limited to 'src/enet/protocol.c')
-rw-r--r-- | src/enet/protocol.c | 1671 |
1 files changed, 1671 insertions, 0 deletions
diff --git a/src/enet/protocol.c b/src/enet/protocol.c new file mode 100644 index 000000000..8e26dfb24 --- /dev/null +++ b/src/enet/protocol.c @@ -0,0 +1,1671 @@ +/** + @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), +}; + +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; + ENetListIterator currentCommand; + ENetProtocolCommand commandNumber; + + 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; + } + + 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) + { + 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; + + 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 (* 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 (* 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 (* 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 (* 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 (fragmentOffset >= totalLength || + fragmentOffset + fragmentLength > totalLength || + fragmentNumber >= fragmentCount) + 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; + hostCommand.sendFragment.startSequenceNumber = startSequenceNumber; + hostCommand.sendFragment.dataLength = fragmentLength; + hostCommand.sendFragment.fragmentNumber = fragmentNumber; + hostCommand.sendFragment.fragmentCount = fragmentCount; + hostCommand.sendFragment.fragmentOffset = fragmentOffset; + hostCommand.sendFragment.totalLength = totalLength; + + 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_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) + 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 (windowSize < peer -> windowSize) + peer -> windowSize = windowSize; + + peer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> verifyConnect.incomingBandwidth); + peer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> verifyConnect.outgoingBandwidth); + + enet_protocol_notify_connect (host, peer, event); + return 0; +} + +static int +enet_protocol_handle_incoming_commands (ENetHost * host, ENetEvent * event) +{ + ENetProtocolHeader * header; + ENetProtocol * command; + ENetPeer * peer; + enet_uint8 * currentData; + size_t headerSize; + enet_uint16 peerID, flags; + enet_uint8 sessionID; + + if (host -> receivedDataLength < (size_t) & ((ENetProtocolHeader *) 0) -> sentTime) + return 0; + + header = (ENetProtocolHeader *) host -> receivedData; + + peerID = ENET_NET_TO_HOST_16 (header -> peerID); + sessionID = (peerID & ENET_PROTOCOL_HEADER_SESSION_MASK) >> ENET_PROTOCOL_HEADER_SESSION_SHIFT; + flags = peerID & ENET_PROTOCOL_HEADER_FLAG_MASK; + peerID &= ~ (ENET_PROTOCOL_HEADER_FLAG_MASK | ENET_PROTOCOL_HEADER_SESSION_MASK); + + headerSize = (flags & ENET_PROTOCOL_HEADER_FLAG_SENT_TIME ? sizeof (ENetProtocolHeader) : (size_t) & ((ENetProtocolHeader *) 0) -> sentTime); + if (host -> checksum != NULL) + headerSize += sizeof (enet_uint32); + + if (peerID == ENET_PROTOCOL_MAXIMUM_PEER_ID) + peer = NULL; + else + if (peerID >= host -> peerCount) + return 0; + else + { + peer = & host -> peers [peerID]; + + if (peer -> state == ENET_PEER_STATE_DISCONNECTED || + peer -> state == ENET_PEER_STATE_ZOMBIE || + (host -> receivedAddress.host != peer -> address.host && + peer -> address.host != ENET_HOST_BROADCAST) || + (peer -> outgoingPeerID < ENET_PROTOCOL_MAXIMUM_PEER_ID && + sessionID != peer -> incomingSessionID)) + return 0; + } + + if (flags & ENET_PROTOCOL_HEADER_FLAG_COMPRESSED) + { + size_t originalSize; + if (host -> compressor.context == NULL || host -> compressor.decompress == NULL) + return 0; + + originalSize = host -> compressor.decompress (host -> compressor.context, + host -> receivedData + headerSize, + host -> receivedDataLength - headerSize, + host -> packetData [1] + headerSize, + sizeof (host -> packetData [1]) - headerSize); + if (originalSize <= 0 || originalSize > sizeof (host -> packetData [1]) - headerSize) + return 0; + + memcpy (host -> packetData [1], header, headerSize); + host -> receivedData = host -> packetData [1]; + host -> receivedDataLength = headerSize + originalSize; + } + + if (host -> checksum != NULL) + { + enet_uint32 * checksum = (enet_uint32 *) & host -> receivedData [headerSize - sizeof (enet_uint32)], + desiredChecksum = * checksum; + ENetBuffer buffer; + + * checksum = peer != NULL ? peer -> connectID : 0; + + buffer.data = host -> receivedData; + buffer.dataLength = host -> receivedDataLength; + + if (host -> checksum (& buffer, 1) != desiredChecksum) + return 0; + } + + if (peer != NULL) + { + peer -> address.host = host -> receivedAddress.host; + peer -> address.port = host -> receivedAddress.port; + peer -> incomingDataTotal += host -> receivedDataLength; + } + + currentData = host -> receivedData + headerSize; + + while (currentData < & host -> receivedData [host -> receivedDataLength]) + { + enet_uint8 commandNumber; + size_t commandSize; + + command = (ENetProtocol *) currentData; + + if (currentData + sizeof (ENetProtocolCommandHeader) > & host -> receivedData [host -> receivedDataLength]) + break; + + commandNumber = command -> header.command & ENET_PROTOCOL_COMMAND_MASK; + if (commandNumber >= ENET_PROTOCOL_COMMAND_COUNT) + break; + + commandSize = commandSizes [commandNumber]; + if (commandSize == 0 || currentData + commandSize > & host -> receivedData [host -> receivedDataLength]) + break; + + currentData += commandSize; + + if (peer == NULL && commandNumber != ENET_PROTOCOL_COMMAND_CONNECT) + break; + + command -> header.reliableSequenceNumber = ENET_NET_TO_HOST_16 (command -> header.reliableSequenceNumber); + + switch (command -> header.command & ENET_PROTOCOL_COMMAND_MASK) + { + case ENET_PROTOCOL_COMMAND_ACKNOWLEDGE: + if (enet_protocol_handle_acknowledge (host, event, peer, command)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_CONNECT: + peer = enet_protocol_handle_connect (host, header, command); + if (peer == NULL) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_VERIFY_CONNECT: + if (enet_protocol_handle_verify_connect (host, event, peer, command)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_DISCONNECT: + if (enet_protocol_handle_disconnect (host, peer, command)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_PING: + if (enet_protocol_handle_ping (host, peer, command)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_SEND_RELIABLE: + if (enet_protocol_handle_send_reliable (host, peer, command, & currentData)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_SEND_UNRELIABLE: + if (enet_protocol_handle_send_unreliable (host, peer, command, & currentData)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_SEND_UNSEQUENCED: + if (enet_protocol_handle_send_unsequenced (host, peer, command, & currentData)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_SEND_FRAGMENT: + if (enet_protocol_handle_send_fragment (host, peer, command, & currentData)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_BANDWIDTH_LIMIT: + if (enet_protocol_handle_bandwidth_limit (host, peer, command)) + goto commandError; + break; + + case ENET_PROTOCOL_COMMAND_THROTTLE_CONFIGURE: + if (enet_protocol_handle_throttle_configure (host, peer, command)) + goto commandError; + break; + + default: + goto commandError; + } + + if (peer != NULL && + (command -> header.command & ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE) != 0) + { + enet_uint16 sentTime; + + if (! (flags & ENET_PROTOCOL_HEADER_FLAG_SENT_TIME)) + break; + + sentTime = ENET_NET_TO_HOST_16 (header -> sentTime); + + switch (peer -> state) + { + case ENET_PEER_STATE_DISCONNECTING: + case ENET_PEER_STATE_ACKNOWLEDGING_CONNECT: + break; + + case ENET_PEER_STATE_ACKNOWLEDGING_DISCONNECT: + if ((command -> header.command & ENET_PROTOCOL_COMMAND_MASK) == ENET_PROTOCOL_COMMAND_DISCONNECT) + enet_peer_queue_acknowledgement (peer, command, sentTime); + break; + + default: + enet_peer_queue_acknowledgement (peer, command, sentTime); + break; + } + } + } + +commandError: + if (event != NULL && event -> type != ENET_EVENT_TYPE_NONE) + return 1; + + return 0; +} + +static int +enet_protocol_receive_incoming_commands (ENetHost * host, ENetEvent * event) +{ + for (;;) + { + int receivedLength; + ENetBuffer buffer; + + buffer.data = host -> packetData [0]; + buffer.dataLength = sizeof (host -> packetData [0]); + + receivedLength = enet_socket_receive (host -> socket, + & host -> receivedAddress, + & buffer, + 1); + + if (receivedLength < 0) + return -1; + + if (receivedLength == 0) + return 0; + + host -> receivedData = host -> packetData [0]; + host -> receivedDataLength = receivedLength; + + host -> totalReceivedData += receivedLength; + host -> totalReceivedPackets ++; + + switch (enet_protocol_handle_incoming_commands (host, event)) + { + case 1: + return 1; + + case -1: + return -1; + + default: + break; + } + } + + return -1; +} + +static void +enet_protocol_send_acknowledgements (ENetHost * host, ENetPeer * peer) +{ + ENetProtocol * command = & host -> commands [host -> commandCount]; + ENetBuffer * buffer = & host -> buffers [host -> bufferCount]; + ENetAcknowledgement * acknowledgement; + ENetListIterator currentAcknowledgement; + + currentAcknowledgement = enet_list_begin (& peer -> acknowledgements); + + while (currentAcknowledgement != enet_list_end (& peer -> acknowledgements)) + { + if (command >= & host -> commands [sizeof (host -> commands) / sizeof (ENetProtocol)] || + buffer >= & host -> buffers [sizeof (host -> buffers) / sizeof (ENetBuffer)] || + peer -> mtu - host -> packetSize < sizeof (ENetProtocolAcknowledge)) + { + host -> continueSending = 1; + + break; + } + + acknowledgement = (ENetAcknowledgement *) currentAcknowledgement; + + currentAcknowledgement = enet_list_next (currentAcknowledgement); + + buffer -> data = command; + buffer -> dataLength = sizeof (ENetProtocolAcknowledge); + + host -> packetSize += buffer -> dataLength; + + command -> header.command = ENET_PROTOCOL_COMMAND_ACKNOWLEDGE; + command -> header.channelID = acknowledgement -> command.header.channelID; + command -> acknowledge.receivedReliableSequenceNumber = ENET_HOST_TO_NET_16 (acknowledgement -> command.header.reliableSequenceNumber); + command -> acknowledge.receivedSentTime = ENET_HOST_TO_NET_16 (acknowledgement -> sentTime); + + if ((acknowledgement -> command.header.command & ENET_PROTOCOL_COMMAND_MASK) == ENET_PROTOCOL_COMMAND_DISCONNECT) + enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE); + + enet_list_remove (& acknowledgement -> acknowledgementList); + enet_free (acknowledgement); + + ++ command; + ++ buffer; + } + + host -> commandCount = command - host -> commands; + host -> bufferCount = buffer - host -> buffers; +} + +static void +enet_protocol_send_unreliable_outgoing_commands (ENetHost * host, ENetPeer * peer) +{ + ENetProtocol * command = & host -> commands [host -> commandCount]; + ENetBuffer * buffer = & host -> buffers [host -> bufferCount]; + ENetOutgoingCommand * outgoingCommand; + ENetListIterator currentCommand; + + currentCommand = enet_list_begin (& peer -> outgoingUnreliableCommands); + + while (currentCommand != enet_list_end (& peer -> outgoingUnreliableCommands)) + { + size_t commandSize; + + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + commandSize = commandSizes [outgoingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK]; + + if (command >= & host -> commands [sizeof (host -> commands) / sizeof (ENetProtocol)] || + buffer + 1 >= & host -> buffers [sizeof (host -> buffers) / sizeof (ENetBuffer)] || + peer -> mtu - host -> packetSize < commandSize || + (outgoingCommand -> packet != NULL && + peer -> mtu - host -> packetSize < commandSize + outgoingCommand -> packet -> dataLength)) + { + host -> continueSending = 1; + + break; + } + + currentCommand = enet_list_next (currentCommand); + + if (outgoingCommand -> packet != NULL) + { + peer -> packetThrottleCounter += ENET_PEER_PACKET_THROTTLE_COUNTER; + peer -> packetThrottleCounter %= ENET_PEER_PACKET_THROTTLE_SCALE; + + if (peer -> packetThrottleCounter > peer -> packetThrottle) + { + -- outgoingCommand -> packet -> referenceCount; + + if (outgoingCommand -> packet -> referenceCount == 0) + enet_packet_destroy (outgoingCommand -> packet); + + enet_list_remove (& outgoingCommand -> outgoingCommandList); + enet_free (outgoingCommand); + + continue; + } + } + + buffer -> data = command; + buffer -> dataLength = commandSize; + + host -> packetSize += buffer -> dataLength; + + * command = outgoingCommand -> command; + + enet_list_remove (& outgoingCommand -> outgoingCommandList); + + if (outgoingCommand -> packet != NULL) + { + ++ buffer; + + buffer -> data = outgoingCommand -> packet -> data; + buffer -> dataLength = outgoingCommand -> packet -> dataLength; + + host -> packetSize += buffer -> dataLength; + + enet_list_insert (enet_list_end (& peer -> sentUnreliableCommands), outgoingCommand); + } + else + enet_free (outgoingCommand); + + ++ command; + ++ buffer; + } + + host -> commandCount = command - host -> commands; + host -> bufferCount = buffer - host -> buffers; + + if (peer -> state == ENET_PEER_STATE_DISCONNECT_LATER && + enet_list_empty (& peer -> outgoingReliableCommands) && + enet_list_empty (& peer -> outgoingUnreliableCommands) && + enet_list_empty (& peer -> sentReliableCommands)) + enet_peer_disconnect (peer, peer -> eventData); +} + +static int +enet_protocol_check_timeouts (ENetHost * host, ENetPeer * peer, ENetEvent * event) +{ + ENetOutgoingCommand * outgoingCommand; + ENetListIterator currentCommand, insertPosition; + + currentCommand = enet_list_begin (& peer -> sentReliableCommands); + insertPosition = enet_list_begin (& peer -> outgoingReliableCommands); + + while (currentCommand != enet_list_end (& peer -> sentReliableCommands)) + { + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + + currentCommand = enet_list_next (currentCommand); + + if (ENET_TIME_DIFFERENCE (host -> serviceTime, outgoingCommand -> sentTime) < outgoingCommand -> roundTripTimeout) + continue; + + if (peer -> earliestTimeout == 0 || + ENET_TIME_LESS (outgoingCommand -> sentTime, peer -> earliestTimeout)) + peer -> earliestTimeout = outgoingCommand -> sentTime; + + if (peer -> earliestTimeout != 0 && + (ENET_TIME_DIFFERENCE (host -> serviceTime, peer -> earliestTimeout) >= ENET_PEER_TIMEOUT_MAXIMUM || + (outgoingCommand -> roundTripTimeout >= outgoingCommand -> roundTripTimeoutLimit && + ENET_TIME_DIFFERENCE (host -> serviceTime, peer -> earliestTimeout) >= ENET_PEER_TIMEOUT_MINIMUM))) + { + enet_protocol_notify_disconnect (host, peer, event); + + return 1; + } + + if (outgoingCommand -> packet != NULL) + peer -> reliableDataInTransit -= outgoingCommand -> fragmentLength; + + ++ peer -> packetsLost; + + outgoingCommand -> roundTripTimeout *= 2; + + enet_list_insert (insertPosition, enet_list_remove (& outgoingCommand -> outgoingCommandList)); + + if (currentCommand == enet_list_begin (& peer -> sentReliableCommands) && + ! enet_list_empty (& peer -> sentReliableCommands)) + { + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + + peer -> nextTimeout = outgoingCommand -> sentTime + outgoingCommand -> roundTripTimeout; + } + } + + return 0; +} + +static void +enet_protocol_send_reliable_outgoing_commands (ENetHost * host, ENetPeer * peer) +{ + ENetProtocol * command = & host -> commands [host -> commandCount]; + ENetBuffer * buffer = & host -> buffers [host -> bufferCount]; + ENetOutgoingCommand * outgoingCommand; + ENetListIterator currentCommand; + ENetChannel *channel; + enet_uint16 reliableWindow; + size_t commandSize; + + currentCommand = enet_list_begin (& peer -> outgoingReliableCommands); + + while (currentCommand != enet_list_end (& peer -> outgoingReliableCommands)) + { + outgoingCommand = (ENetOutgoingCommand *) currentCommand; + + channel = outgoingCommand -> command.header.channelID < peer -> channelCount ? & peer -> channels [outgoingCommand -> command.header.channelID] : NULL; + reliableWindow = outgoingCommand -> reliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE; + if (channel != NULL && + outgoingCommand -> sendAttempts < 1 && + ! (outgoingCommand -> reliableSequenceNumber % ENET_PEER_RELIABLE_WINDOW_SIZE) && + (channel -> reliableWindows [(reliableWindow + ENET_PEER_RELIABLE_WINDOWS - 1) % ENET_PEER_RELIABLE_WINDOWS] >= ENET_PEER_RELIABLE_WINDOW_SIZE || + channel -> usedReliableWindows & ((((1 << ENET_PEER_FREE_RELIABLE_WINDOWS) - 1) << reliableWindow) | + (((1 << ENET_PEER_FREE_RELIABLE_WINDOWS) - 1) >> (ENET_PEER_RELIABLE_WINDOW_SIZE - reliableWindow))))) + break; + + commandSize = commandSizes [outgoingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK]; + if (command >= & host -> commands [sizeof (host -> commands) / sizeof (ENetProtocol)] || + buffer + 1 >= & host -> buffers [sizeof (host -> buffers) / sizeof (ENetBuffer)] || + peer -> mtu - host -> packetSize < commandSize) + { + host -> continueSending = 1; + + break; + } + + if (outgoingCommand -> packet != NULL) + { + if (peer -> reliableDataInTransit + outgoingCommand -> fragmentLength > peer -> windowSize) + break; + + if ((enet_uint16) (peer -> mtu - host -> packetSize) < (enet_uint16) (commandSize + outgoingCommand -> fragmentLength)) + { + host -> continueSending = 1; + + break; + } + } + + currentCommand = enet_list_next (currentCommand); + + if (channel != NULL && outgoingCommand -> sendAttempts < 1) + { + channel -> usedReliableWindows |= 1 << reliableWindow; + ++ channel -> reliableWindows [reliableWindow]; + } + + ++ outgoingCommand -> sendAttempts; + + if (outgoingCommand -> roundTripTimeout == 0) + { + outgoingCommand -> roundTripTimeout = peer -> roundTripTime + 4 * peer -> roundTripTimeVariance; + outgoingCommand -> roundTripTimeoutLimit = ENET_PEER_TIMEOUT_LIMIT * outgoingCommand -> roundTripTimeout; + } + + if (enet_list_empty (& peer -> sentReliableCommands)) + peer -> nextTimeout = host -> serviceTime + outgoingCommand -> roundTripTimeout; + + enet_list_insert (enet_list_end (& peer -> sentReliableCommands), + enet_list_remove (& outgoingCommand -> outgoingCommandList)); + + outgoingCommand -> sentTime = host -> serviceTime; + + buffer -> data = command; + buffer -> dataLength = commandSize; + + host -> packetSize += buffer -> dataLength; + host -> headerFlags |= ENET_PROTOCOL_HEADER_FLAG_SENT_TIME; + + * command = outgoingCommand -> command; + + if (outgoingCommand -> packet != NULL) + { + ++ buffer; + + buffer -> data = outgoingCommand -> packet -> data + outgoingCommand -> fragmentOffset; + buffer -> dataLength = outgoingCommand -> fragmentLength; + + host -> packetSize += outgoingCommand -> fragmentLength; + + peer -> reliableDataInTransit += outgoingCommand -> fragmentLength; + } + + ++ peer -> packetsSent; + + ++ command; + ++ buffer; + } + + host -> commandCount = command - host -> commands; + host -> bufferCount = buffer - host -> buffers; +} + +static int +enet_protocol_send_outgoing_commands (ENetHost * host, ENetEvent * event, int checkForTimeouts) +{ + enet_uint8 headerData [sizeof (ENetProtocolHeader) + sizeof (enet_uint32)]; + ENetProtocolHeader * header = (ENetProtocolHeader *) headerData; + ENetPeer * currentPeer; + int sentLength; + size_t shouldCompress = 0; + + host -> continueSending = 1; + + while (host -> continueSending) + for (host -> continueSending = 0, + currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + if (currentPeer -> state == ENET_PEER_STATE_DISCONNECTED || + currentPeer -> state == ENET_PEER_STATE_ZOMBIE) + continue; + + host -> headerFlags = 0; + host -> commandCount = 0; + host -> bufferCount = 1; + host -> packetSize = sizeof (ENetProtocolHeader); + + if (! enet_list_empty (& currentPeer -> acknowledgements)) + enet_protocol_send_acknowledgements (host, currentPeer); + + if (checkForTimeouts != 0 && + ! enet_list_empty (& currentPeer -> sentReliableCommands) && + ENET_TIME_GREATER_EQUAL (host -> serviceTime, currentPeer -> nextTimeout) && + enet_protocol_check_timeouts (host, currentPeer, event) == 1) + return 1; + + if (! enet_list_empty (& currentPeer -> outgoingReliableCommands)) + enet_protocol_send_reliable_outgoing_commands (host, currentPeer); + else + if (enet_list_empty (& currentPeer -> sentReliableCommands) && + ENET_TIME_DIFFERENCE (host -> serviceTime, currentPeer -> lastReceiveTime) >= ENET_PEER_PING_INTERVAL && + currentPeer -> mtu - host -> packetSize >= sizeof (ENetProtocolPing)) + { + enet_peer_ping (currentPeer); + enet_protocol_send_reliable_outgoing_commands (host, currentPeer); + } + + if (! enet_list_empty (& currentPeer -> outgoingUnreliableCommands)) + enet_protocol_send_unreliable_outgoing_commands (host, currentPeer); + + if (host -> commandCount == 0) + continue; + + if (currentPeer -> packetLossEpoch == 0) + currentPeer -> packetLossEpoch = host -> serviceTime; + else + if (ENET_TIME_DIFFERENCE (host -> serviceTime, currentPeer -> packetLossEpoch) >= ENET_PEER_PACKET_LOSS_INTERVAL && + currentPeer -> packetsSent > 0) + { + enet_uint32 packetLoss = currentPeer -> packetsLost * ENET_PEER_PACKET_LOSS_SCALE / currentPeer -> packetsSent; + +#ifdef ENET_DEBUG +#ifdef WIN32 + printf ( +#else + fprintf (stderr, +#endif + "peer %u: %f%%+-%f%% packet loss, %u+-%u ms round trip time, %f%% throttle, %u/%u outgoing, %u/%u incoming\n", currentPeer -> incomingPeerID, currentPeer -> packetLoss / (float) ENET_PEER_PACKET_LOSS_SCALE, currentPeer -> packetLossVariance / (float) ENET_PEER_PACKET_LOSS_SCALE, currentPeer -> roundTripTime, currentPeer -> roundTripTimeVariance, currentPeer -> packetThrottle / (float) ENET_PEER_PACKET_THROTTLE_SCALE, enet_list_size (& currentPeer -> outgoingReliableCommands), enet_list_size (& currentPeer -> outgoingUnreliableCommands), currentPeer -> channels != NULL ? enet_list_size (& currentPeer -> channels -> incomingReliableCommands) : 0, currentPeer -> channels != NULL ? enet_list_size (& currentPeer -> channels -> incomingUnreliableCommands) : 0); +#endif + + currentPeer -> packetLossVariance -= currentPeer -> packetLossVariance / 4; + + if (packetLoss >= currentPeer -> packetLoss) + { + currentPeer -> packetLoss += (packetLoss - currentPeer -> packetLoss) / 8; + currentPeer -> packetLossVariance += (packetLoss - currentPeer -> packetLoss) / 4; + } + else + { + currentPeer -> packetLoss -= (currentPeer -> packetLoss - packetLoss) / 8; + currentPeer -> packetLossVariance += (currentPeer -> packetLoss - packetLoss) / 4; + } + + currentPeer -> packetLossEpoch = host -> serviceTime; + currentPeer -> packetsSent = 0; + currentPeer -> packetsLost = 0; + } + + host -> buffers -> data = headerData; + if (host -> headerFlags & ENET_PROTOCOL_HEADER_FLAG_SENT_TIME) + { + header -> sentTime = ENET_HOST_TO_NET_16 (host -> serviceTime & 0xFFFF); + + host -> buffers -> dataLength = sizeof (ENetProtocolHeader); + } + else + host -> buffers -> dataLength = (size_t) & ((ENetProtocolHeader *) 0) -> sentTime; + + shouldCompress = 0; + if (host -> compressor.context != NULL && host -> compressor.compress != NULL) + { + size_t originalSize = host -> packetSize - sizeof(ENetProtocolHeader), + compressedSize = host -> compressor.compress (host -> compressor.context, + & host -> buffers [1], host -> bufferCount - 1, + originalSize, + host -> packetData [1], + originalSize); + if (compressedSize > 0 && compressedSize < originalSize) + { + host -> headerFlags |= ENET_PROTOCOL_HEADER_FLAG_COMPRESSED; + shouldCompress = compressedSize; +#ifdef ENET_DEBUG_COMPRESS +#ifdef WIN32 + printf ( +#else + fprintf (stderr, +#endif + "peer %u: compressed %u -> %u (%u%%)\n", currentPeer -> incomingPeerID, originalSize, compressedSize, (compressedSize * 100) / originalSize); +#endif + } + } + + if (currentPeer -> outgoingPeerID < ENET_PROTOCOL_MAXIMUM_PEER_ID) + host -> headerFlags |= currentPeer -> outgoingSessionID << ENET_PROTOCOL_HEADER_SESSION_SHIFT; + header -> peerID = ENET_HOST_TO_NET_16 (currentPeer -> outgoingPeerID | host -> headerFlags); + if (host -> checksum != NULL) + { + enet_uint32 * checksum = (enet_uint32 *) & headerData [host -> buffers -> dataLength]; + * checksum = currentPeer -> outgoingPeerID < ENET_PROTOCOL_MAXIMUM_PEER_ID ? currentPeer -> connectID : 0; + host -> buffers -> dataLength += sizeof (enet_uint32); + * checksum = host -> checksum (host -> buffers, host -> bufferCount); + } + + if (shouldCompress > 0) + { + host -> buffers [1].data = host -> packetData [1]; + host -> buffers [1].dataLength = shouldCompress; + host -> bufferCount = 2; + } + + currentPeer -> lastSendTime = host -> serviceTime; + + sentLength = enet_socket_send (host -> socket, & currentPeer -> address, host -> buffers, host -> bufferCount); + + enet_protocol_remove_sent_unreliable_commands (currentPeer); + + if (sentLength < 0) + return -1; + + host -> totalSentData += sentLength; + host -> totalSentPackets ++; + } + + return 0; +} + +/** Sends any queued packets on the host specified to its designated peers. + + @param host host to flush + @remarks this function need only be used in circumstances where one wishes to send queued packets earlier than in a call to enet_host_service(). + @ingroup host +*/ +void +enet_host_flush (ENetHost * host) +{ + host -> serviceTime = enet_time_get (); + + enet_protocol_send_outgoing_commands (host, NULL, 0); +} + +/** Checks for any queued events on the host and dispatches one if available. + + @param host host to check for events + @param event an event structure where event details will be placed if available + @retval > 0 if an event was dispatched + @retval 0 if no events are available + @retval < 0 on failure + @ingroup host +*/ +int +enet_host_check_events (ENetHost * host, ENetEvent * event) +{ + if (event == NULL) return -1; + + event -> type = ENET_EVENT_TYPE_NONE; + event -> peer = NULL; + event -> packet = NULL; + + return enet_protocol_dispatch_incoming_commands (host, event); +} + +/** Waits for events on the host specified and shuttles packets between + the host and its peers. + + @param host host to service + @param event an event structure where event details will be placed if one occurs + if event == NULL then no events will be delivered + @param timeout number of milliseconds that ENet should wait for events + @retval > 0 if an event occurred within the specified time limit + @retval 0 if no event occurred + @retval < 0 on failure + @remarks enet_host_service should be called fairly regularly for adequate performance + @ingroup host +*/ +int +enet_host_service (ENetHost * host, ENetEvent * event, enet_uint32 timeout) +{ + enet_uint32 waitCondition; + + if (event != NULL) + { + event -> type = ENET_EVENT_TYPE_NONE; + event -> peer = NULL; + event -> packet = NULL; + + switch (enet_protocol_dispatch_incoming_commands (host, event)) + { + case 1: + return 1; + + case -1: + perror ("Error dispatching incoming packets"); + + return -1; + + default: + break; + } + } + + host -> serviceTime = enet_time_get (); + + timeout += host -> serviceTime; + + do + { + if (ENET_TIME_DIFFERENCE (host -> serviceTime, host -> bandwidthThrottleEpoch) >= ENET_HOST_BANDWIDTH_THROTTLE_INTERVAL) + enet_host_bandwidth_throttle (host); + + switch (enet_protocol_send_outgoing_commands (host, event, 1)) + { + case 1: + return 1; + + case -1: + perror ("Error sending outgoing packets"); + + return -1; + + default: + break; + } + + switch (enet_protocol_receive_incoming_commands (host, event)) + { + case 1: + return 1; + + case -1: + perror ("Error receiving incoming packets"); + + return -1; + + default: + break; + } + + switch (enet_protocol_send_outgoing_commands (host, event, 1)) + { + case 1: + return 1; + + case -1: + perror ("Error sending outgoing packets"); + + return -1; + + default: + break; + } + + if (event != NULL) + { + switch (enet_protocol_dispatch_incoming_commands (host, event)) + { + case 1: + return 1; + + case -1: + perror ("Error dispatching incoming packets"); + + return -1; + + default: + break; + } + } + + host -> serviceTime = enet_time_get (); + + if (ENET_TIME_GREATER_EQUAL (host -> serviceTime, timeout)) + return 0; + + waitCondition = ENET_SOCKET_WAIT_RECEIVE; + + if (enet_socket_wait (host -> socket, & waitCondition, ENET_TIME_DIFFERENCE (timeout, host -> serviceTime)) != 0) + return -1; + + host -> serviceTime = enet_time_get (); + } while (waitCondition == ENET_SOCKET_WAIT_RECEIVE); + + return 0; +} + |