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-rw-r--r--thirdparty/enet/protocol.c1914
1 files changed, 1914 insertions, 0 deletions
diff --git a/thirdparty/enet/protocol.c b/thirdparty/enet/protocol.c
new file mode 100644
index 0000000000..4a2a4ed185
--- /dev/null
+++ b/thirdparty/enet/protocol.c
@@ -0,0 +1,1914 @@
+/**
+ @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 void
+enet_protocol_change_state (ENetHost * host, ENetPeer * peer, ENetPeerState state)
+{
+ if (state == ENET_PEER_STATE_CONNECTED || state == ENET_PEER_STATE_DISCONNECT_LATER)
+ enet_peer_on_connect (peer);
+ else
+ enet_peer_on_disconnect (peer);
+
+ peer -> state = state;
+}
+
+static void
+enet_protocol_dispatch_state (ENetHost * host, ENetPeer * peer, ENetPeerState state)
+{
+ enet_protocol_change_state (host, peer, state);
+
+ if (! peer -> needsDispatch)
+ {
+ enet_list_insert (enet_list_end (& host -> dispatchQueue), & peer -> dispatchList);
+
+ peer -> needsDispatch = 1;
+ }
+}
+
+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:
+ enet_protocol_change_state (host, peer, 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;
+
+ default:
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static void
+enet_protocol_notify_connect (ENetHost * host, ENetPeer * peer, ENetEvent * event)
+{
+ host -> recalculateBandwidthLimits = 1;
+
+ if (event != NULL)
+ {
+ enet_protocol_change_state (host, peer, 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)
+ {
+ outgoingCommand -> packet -> flags |= ENET_PACKET_FLAG_SENT;
+
+ 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 (outgoingCommand == NULL)
+ 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)
+ {
+ if (wasSent)
+ peer -> reliableDataInTransit -= outgoingCommand -> fragmentLength;
+
+ -- outgoingCommand -> packet -> referenceCount;
+
+ if (outgoingCommand -> packet -> referenceCount == 0)
+ {
+ outgoingCommand -> packet -> flags |= ENET_PACKET_FLAG_SENT;
+
+ 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, duplicatePeers = 0;
+ ENetPeer * currentPeer, * peer = NULL;
+ 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)
+ {
+ if (peer == NULL)
+ peer = currentPeer;
+ }
+ else
+ if (currentPeer -> state != ENET_PEER_STATE_CONNECTING &&
+ currentPeer -> address.host == host -> receivedAddress.host)
+ {
+ if (currentPeer -> address.port == host -> receivedAddress.port &&
+ currentPeer -> connectID == command -> connect.connectID)
+ return NULL;
+
+ ++ duplicatePeers;
+ }
+ }
+
+ if (peer == NULL || duplicatePeers >= host -> duplicatePeers)
+ return NULL;
+
+ if (channelCount > host -> channelLimit)
+ channelCount = host -> channelLimit;
+ peer -> channels = (ENetChannel *) enet_malloc (channelCount * sizeof (ENetChannel));
+ if (peer -> channels == NULL)
+ return NULL;
+ peer -> channelCount = channelCount;
+ peer -> state = ENET_PEER_STATE_ACKNOWLEDGING_CONNECT;
+ peer -> connectID = command -> connect.connectID;
+ peer -> address = host -> receivedAddress;
+ peer -> outgoingPeerID = ENET_NET_TO_HOST_16 (command -> connect.outgoingPeerID);
+ peer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.incomingBandwidth);
+ peer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.outgoingBandwidth);
+ peer -> packetThrottleInterval = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleInterval);
+ peer -> packetThrottleAcceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleAcceleration);
+ peer -> packetThrottleDeceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleDeceleration);
+ peer -> eventData = ENET_NET_TO_HOST_32 (command -> connect.data);
+
+ incomingSessionID = command -> connect.incomingSessionID == 0xFF ? peer -> outgoingSessionID : command -> connect.incomingSessionID;
+ incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
+ if (incomingSessionID == peer -> outgoingSessionID)
+ incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
+ peer -> outgoingSessionID = incomingSessionID;
+
+ outgoingSessionID = command -> connect.outgoingSessionID == 0xFF ? peer -> incomingSessionID : command -> connect.outgoingSessionID;
+ outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
+ if (outgoingSessionID == peer -> incomingSessionID)
+ outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
+ peer -> incomingSessionID = outgoingSessionID;
+
+ for (channel = peer -> channels;
+ channel < & peer -> 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;
+
+ peer -> mtu = mtu;
+
+ if (host -> outgoingBandwidth == 0 &&
+ peer -> incomingBandwidth == 0)
+ peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
+ else
+ if (host -> outgoingBandwidth == 0 ||
+ peer -> incomingBandwidth == 0)
+ peer -> windowSize = (ENET_MAX (host -> outgoingBandwidth, peer -> incomingBandwidth) /
+ ENET_PEER_WINDOW_SIZE_SCALE) *
+ ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
+ else
+ peer -> windowSize = (ENET_MIN (host -> outgoingBandwidth, peer -> incomingBandwidth) /
+ 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;
+
+ 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 (peer -> incomingPeerID);
+ verifyCommand.verifyConnect.incomingSessionID = incomingSessionID;
+ verifyCommand.verifyConnect.outgoingSessionID = outgoingSessionID;
+ verifyCommand.verifyConnect.mtu = ENET_HOST_TO_NET_32 (peer -> 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 (peer -> packetThrottleInterval);
+ verifyCommand.verifyConnect.packetThrottleAcceleration = ENET_HOST_TO_NET_32 (peer -> packetThrottleAcceleration);
+ verifyCommand.verifyConnect.packetThrottleDeceleration = ENET_HOST_TO_NET_32 (peer -> packetThrottleDeceleration);
+ verifyCommand.verifyConnect.connectID = peer -> connectID;
+
+ enet_peer_queue_outgoing_command (peer, & verifyCommand, NULL, 0, 0);
+
+ return peer;
+}
+
+static int
+enet_protocol_handle_send_reliable (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData)
+{
+ 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 > host -> maximumPacketSize ||
+ * currentData < host -> receivedData ||
+ * currentData > & host -> receivedData [host -> receivedDataLength])
+ return -1;
+
+ if (enet_peer_queue_incoming_command (peer, command, (const enet_uint8 *) command + sizeof (ENetProtocolSendReliable), dataLength, ENET_PACKET_FLAG_RELIABLE, 0) == NULL)
+ return -1;
+
+ return 0;
+}
+
+static int
+enet_protocol_handle_send_unsequenced (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData)
+{
+ 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 > host -> maximumPacketSize ||
+ * 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;
+
+ if (enet_peer_queue_incoming_command (peer, command, (const enet_uint8 *) command + sizeof (ENetProtocolSendUnsequenced), dataLength, ENET_PACKET_FLAG_UNSEQUENCED, 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)
+{
+ 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 > host -> maximumPacketSize ||
+ * currentData < host -> receivedData ||
+ * currentData > & host -> receivedData [host -> receivedDataLength])
+ return -1;
+
+ if (enet_peer_queue_incoming_command (peer, command, (const enet_uint8 *) command + sizeof (ENetProtocolSendUnreliable), dataLength, 0, 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 > host -> maximumPacketSize ||
+ * 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 > host -> maximumPacketSize ||
+ 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;
+
+ hostCommand.header.reliableSequenceNumber = startSequenceNumber;
+
+ startCommand = enet_peer_queue_incoming_command (peer, & hostCommand, NULL, totalLength, ENET_PACKET_FLAG_RELIABLE, 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 > host -> maximumPacketSize ||
+ * 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 > host -> maximumPacketSize ||
+ 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)
+ {
+ startCommand = enet_peer_queue_incoming_command (peer, command, NULL, totalLength, ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT, 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)
+{
+ if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)
+ return -1;
+
+ return 0;
+}
+
+static int
+enet_protocol_handle_bandwidth_limit (ENetHost * host, ENetPeer * peer, const ENetProtocol * command)
+{
+ if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)
+ return -1;
+
+ if (peer -> incomingBandwidth != 0)
+ -- host -> bandwidthLimitedPeers;
+
+ 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 -> bandwidthLimitedPeers;
+
+ if (peer -> incomingBandwidth == 0 && host -> outgoingBandwidth == 0)
+ peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
+ else
+ if (peer -> incomingBandwidth == 0 || host -> outgoingBandwidth == 0)
+ peer -> windowSize = (ENET_MAX (peer -> incomingBandwidth, host -> outgoingBandwidth) /
+ ENET_PEER_WINDOW_SIZE_SCALE) * ENET_PROTOCOL_MINIMUM_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)
+{
+ if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)
+ return -1;
+
+ 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_DISCONNECTED || 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 || peer -> state == ENET_PEER_STATE_CONNECTING)
+ 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)
+ enet_protocol_change_state (host, peer, 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;
+
+ if (peer -> state == ENET_PEER_STATE_DISCONNECTED || peer -> state == ENET_PEER_STATE_ZOMBIE)
+ return 0;
+
+ 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;
+
+ default:
+ 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 ||
+ host -> receivedAddress.port != peer -> address.port) &&
+ 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 (commandNumber)
+ {
+ case ENET_PROTOCOL_COMMAND_ACKNOWLEDGE:
+ if (enet_protocol_handle_acknowledge (host, event, peer, command))
+ goto commandError;
+ break;
+
+ case ENET_PROTOCOL_COMMAND_CONNECT:
+ if (peer != NULL)
+ goto commandError;
+ 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;
+
+ case ENET_PROTOCOL_COMMAND_SEND_UNRELIABLE_FRAGMENT:
+ if (enet_protocol_handle_send_unreliable_fragment (host, peer, command, & currentData))
+ 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:
+ case ENET_PEER_STATE_DISCONNECTED:
+ case ENET_PEER_STATE_ZOMBIE:
+ 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)
+{
+ int packets;
+
+ for (packets = 0; packets < 256; ++ packets)
+ {
+ 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 ++;
+
+ if (host -> intercept != NULL)
+ {
+ switch (host -> intercept (host, event))
+ {
+ case 1:
+ if (event != NULL && event -> type != ENET_EVENT_TYPE_NONE)
+ return 1;
+
+ continue;
+
+ case -1:
+ return -1;
+
+ default:
+ break;
+ }
+ }
+
+ 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;
+ enet_uint16 reliableSequenceNumber;
+
+ 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;
+
+ reliableSequenceNumber = ENET_HOST_TO_NET_16 (acknowledgement -> command.header.reliableSequenceNumber);
+
+ command -> header.command = ENET_PROTOCOL_COMMAND_ACKNOWLEDGE;
+ command -> header.channelID = acknowledgement -> command.header.channelID;
+ command -> header.reliableSequenceNumber = reliableSequenceNumber;
+ command -> acknowledge.receivedReliableSequenceNumber = 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 -> fragmentLength))
+ {
+ host -> continueSending = 1;
+
+ break;
+ }
+
+ currentCommand = enet_list_next (currentCommand);
+
+ if (outgoingCommand -> packet != NULL && outgoingCommand -> fragmentOffset == 0)
+ {
+ peer -> packetThrottleCounter += ENET_PEER_PACKET_THROTTLE_COUNTER;
+ peer -> packetThrottleCounter %= ENET_PEER_PACKET_THROTTLE_SCALE;
+
+ if (peer -> packetThrottleCounter > peer -> packetThrottle)
+ {
+ enet_uint16 reliableSequenceNumber = outgoingCommand -> reliableSequenceNumber,
+ unreliableSequenceNumber = outgoingCommand -> unreliableSequenceNumber;
+ for (;;)
+ {
+ -- outgoingCommand -> packet -> referenceCount;
+
+ if (outgoingCommand -> packet -> referenceCount == 0)
+ enet_packet_destroy (outgoingCommand -> packet);
+
+ enet_list_remove (& outgoingCommand -> outgoingCommandList);
+ enet_free (outgoingCommand);
+
+ if (currentCommand == enet_list_end (& peer -> outgoingUnreliableCommands))
+ break;
+
+ outgoingCommand = (ENetOutgoingCommand *) currentCommand;
+ if (outgoingCommand -> reliableSequenceNumber != reliableSequenceNumber ||
+ outgoingCommand -> unreliableSequenceNumber != unreliableSequenceNumber)
+ break;
+
+ currentCommand = enet_list_next (currentCommand);
+ }
+
+ 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 + outgoingCommand -> fragmentOffset;
+ buffer -> dataLength = outgoingCommand -> fragmentLength;
+
+ 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) >= peer -> timeoutMaximum ||
+ (outgoingCommand -> roundTripTimeout >= outgoingCommand -> roundTripTimeoutLimit &&
+ ENET_TIME_DIFFERENCE (host -> serviceTime, peer -> earliestTimeout) >= peer -> timeoutMinimum)))
+ {
+ 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 int
+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;
+ int windowExceeded = 0, windowWrap = 0, canPing = 1;
+
+ 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)
+ {
+ if (! windowWrap &&
+ 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_WINDOWS - reliableWindow)))))
+ windowWrap = 1;
+ if (windowWrap)
+ {
+ currentCommand = enet_list_next (currentCommand);
+
+ continue;
+ }
+ }
+
+ if (outgoingCommand -> packet != NULL)
+ {
+ if (! windowExceeded)
+ {
+ enet_uint32 windowSize = (peer -> packetThrottle * peer -> windowSize) / ENET_PEER_PACKET_THROTTLE_SCALE;
+
+ if (peer -> reliableDataInTransit + outgoingCommand -> fragmentLength > ENET_MAX (windowSize, peer -> mtu))
+ windowExceeded = 1;
+ }
+ if (windowExceeded)
+ {
+ currentCommand = enet_list_next (currentCommand);
+
+ continue;
+ }
+ }
+
+ canPing = 0;
+
+ 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 &&
+ (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 = peer -> timeoutLimit * 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;
+
+ return canPing;
+}
+
+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)
+ {
+ if (event != NULL && event -> type != ENET_EVENT_TYPE_NONE)
+ return 1;
+ else
+ continue;
+ }
+
+ if ((enet_list_empty (& currentPeer -> outgoingReliableCommands) ||
+ enet_protocol_send_reliable_outgoing_commands (host, currentPeer)) &&
+ enet_list_empty (& currentPeer -> sentReliableCommands) &&
+ ENET_TIME_DIFFERENCE (host -> serviceTime, currentPeer -> lastReceiveTime) >= currentPeer -> pingInterval &&
+ 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
+ printf ("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
+ printf ("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:
+#ifdef ENET_DEBUG
+ perror ("Error dispatching incoming packets");
+#endif
+
+ 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:
+#ifdef ENET_DEBUG
+ perror ("Error sending outgoing packets");
+#endif
+
+ return -1;
+
+ default:
+ break;
+ }
+
+ switch (enet_protocol_receive_incoming_commands (host, event))
+ {
+ case 1:
+ return 1;
+
+ case -1:
+#ifdef ENET_DEBUG
+ perror ("Error receiving incoming packets");
+#endif
+
+ return -1;
+
+ default:
+ break;
+ }
+
+ switch (enet_protocol_send_outgoing_commands (host, event, 1))
+ {
+ case 1:
+ return 1;
+
+ case -1:
+#ifdef ENET_DEBUG
+ perror ("Error sending outgoing packets");
+#endif
+
+ return -1;
+
+ default:
+ break;
+ }
+
+ if (event != NULL)
+ {
+ switch (enet_protocol_dispatch_incoming_commands (host, event))
+ {
+ case 1:
+ return 1;
+
+ case -1:
+#ifdef ENET_DEBUG
+ perror ("Error dispatching incoming packets");
+#endif
+
+ return -1;
+
+ default:
+ break;
+ }
+ }
+
+ if (ENET_TIME_GREATER_EQUAL (host -> serviceTime, timeout))
+ return 0;
+
+ do
+ {
+ host -> serviceTime = enet_time_get ();
+
+ if (ENET_TIME_GREATER_EQUAL (host -> serviceTime, timeout))
+ return 0;
+
+ waitCondition = ENET_SOCKET_WAIT_RECEIVE | ENET_SOCKET_WAIT_INTERRUPT;
+
+ if (enet_socket_wait (host -> socket, & waitCondition, ENET_TIME_DIFFERENCE (timeout, host -> serviceTime)) != 0)
+ return -1;
+ }
+ while (waitCondition & ENET_SOCKET_WAIT_INTERRUPT);
+
+ host -> serviceTime = enet_time_get ();
+ } while (waitCondition & ENET_SOCKET_WAIT_RECEIVE);
+
+ return 0;
+}
+