Revision b8b57e269c64f67bb4bbd1539da9c1d863077741 authored by Mike Stewart on 07 August 2021, 22:47:38 UTC, committed by Mike Stewart on 07 August 2021, 22:47:38 UTC
1 parent feabfcc
protocol.c
/**
@file protocol.c
@brief ENet protocol functions
*/
#include <stdio.h>
#include <string.h>
#define ENET_BUILDING_LIB 1
#include "enet/utility.h"
#include "enet/time.h"
#include "enet/enet.h"
static size_t commandSizes [ENET_PROTOCOL_COMMAND_COUNT] =
{
0,
sizeof (ENetProtocolAcknowledge),
sizeof (ENetProtocolConnect),
sizeof (ENetProtocolVerifyConnect),
sizeof (ENetProtocolDisconnect),
sizeof (ENetProtocolPing),
sizeof (ENetProtocolSendReliable),
sizeof (ENetProtocolSendUnreliable),
sizeof (ENetProtocolSendFragment),
sizeof (ENetProtocolSendUnsequenced),
sizeof (ENetProtocolBandwidthLimit),
sizeof (ENetProtocolThrottleConfigure),
sizeof (ENetProtocolSendFragment)
};
size_t
enet_protocol_command_size (enet_uint8 commandNumber)
{
return commandSizes [commandNumber & ENET_PROTOCOL_COMMAND_MASK];
}
static int
enet_protocol_dispatch_incoming_commands (ENetHost * host, ENetEvent * event)
{
while (! enet_list_empty (& host -> dispatchQueue))
{
ENetPeer * peer = (ENetPeer *) enet_list_remove (enet_list_begin (& host -> dispatchQueue));
peer -> needsDispatch = 0;
switch (peer -> state)
{
case ENET_PEER_STATE_CONNECTION_PENDING:
case ENET_PEER_STATE_CONNECTION_SUCCEEDED:
peer -> state = ENET_PEER_STATE_CONNECTED;
event -> type = ENET_EVENT_TYPE_CONNECT;
event -> peer = peer;
event -> data = peer -> eventData;
return 1;
case ENET_PEER_STATE_ZOMBIE:
host -> recalculateBandwidthLimits = 1;
event -> type = ENET_EVENT_TYPE_DISCONNECT;
event -> peer = peer;
event -> data = peer -> eventData;
enet_peer_reset (peer);
return 1;
case ENET_PEER_STATE_CONNECTED:
if (enet_list_empty (& peer -> dispatchedCommands))
continue;
event -> packet = enet_peer_receive (peer, & event -> channelID);
if (event -> packet == NULL)
continue;
event -> type = ENET_EVENT_TYPE_RECEIVE;
event -> peer = peer;
if (! enet_list_empty (& peer -> dispatchedCommands))
{
peer -> needsDispatch = 1;
enet_list_insert (enet_list_end (& host -> dispatchQueue), & peer -> dispatchList);
}
return 1;
default:
break;
}
}
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;
int wasSent = 1;
for (currentCommand = enet_list_begin (& peer -> sentReliableCommands);
currentCommand != enet_list_end (& peer -> sentReliableCommands);
currentCommand = enet_list_next (currentCommand))
{
outgoingCommand = (ENetOutgoingCommand *) currentCommand;
if (outgoingCommand -> reliableSequenceNumber == reliableSequenceNumber &&
outgoingCommand -> command.header.channelID == channelID)
break;
}
if (currentCommand == enet_list_end (& peer -> sentReliableCommands))
{
for (currentCommand = enet_list_begin (& peer -> outgoingReliableCommands);
currentCommand != enet_list_end (& peer -> outgoingReliableCommands);
currentCommand = enet_list_next (currentCommand))
{
outgoingCommand = (ENetOutgoingCommand *) currentCommand;
if (outgoingCommand -> sendAttempts < 1) return ENET_PROTOCOL_COMMAND_NONE;
if (outgoingCommand -> reliableSequenceNumber == reliableSequenceNumber &&
outgoingCommand -> command.header.channelID == channelID)
break;
}
if (currentCommand == enet_list_end (& peer -> outgoingReliableCommands))
return ENET_PROTOCOL_COMMAND_NONE;
wasSent = 0;
}
if (channelID < peer -> channelCount)
{
ENetChannel * channel = & peer -> channels [channelID];
enet_uint16 reliableWindow = reliableSequenceNumber / ENET_PEER_RELIABLE_WINDOW_SIZE;
if (channel -> reliableWindows [reliableWindow] > 0)
{
-- channel -> reliableWindows [reliableWindow];
if (! channel -> reliableWindows [reliableWindow])
channel -> usedReliableWindows &= ~ (1 << reliableWindow);
}
}
commandNumber = (ENetProtocolCommand) (outgoingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK);
enet_list_remove (& outgoingCommand -> outgoingCommandList);
if (outgoingCommand -> packet != NULL)
{
if (wasSent)
peer -> reliableDataInTransit -= outgoingCommand -> fragmentLength;
-- outgoingCommand -> packet -> referenceCount;
if (outgoingCommand -> packet -> referenceCount == 0)
enet_packet_destroy (outgoingCommand -> packet);
}
enet_free (outgoingCommand);
if (enet_list_empty (& peer -> sentReliableCommands))
return commandNumber;
outgoingCommand = (ENetOutgoingCommand *) enet_list_front (& peer -> sentReliableCommands);
peer -> nextTimeout = outgoingCommand -> sentTime + outgoingCommand -> roundTripTimeout;
return commandNumber;
}
static ENetPeer *
enet_protocol_handle_connect (ENetHost * host, ENetProtocolHeader * header, ENetProtocol * command)
{
enet_uint8 incomingSessionID, outgoingSessionID;
enet_uint32 mtu, windowSize;
ENetChannel * channel;
size_t channelCount;
ENetPeer * currentPeer;
ENetProtocol verifyCommand;
channelCount = ENET_NET_TO_HOST_32 (command -> connect.channelCount);
if (channelCount < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT ||
channelCount > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT)
return NULL;
for (currentPeer = host -> peers;
currentPeer < & host -> peers [host -> peerCount];
++ currentPeer)
{
if (currentPeer -> state != ENET_PEER_STATE_DISCONNECTED &&
currentPeer -> address.host == host -> receivedAddress.host &&
currentPeer -> address.port == host -> receivedAddress.port &&
currentPeer -> connectID == command -> connect.connectID)
return NULL;
}
for (currentPeer = host -> peers;
currentPeer < & host -> peers [host -> peerCount];
++ currentPeer)
{
if (currentPeer -> state == ENET_PEER_STATE_DISCONNECTED)
break;
}
if (currentPeer >= & host -> peers [host -> peerCount])
return NULL;
if (channelCount > host -> channelLimit)
channelCount = host -> channelLimit;
currentPeer -> channels = (ENetChannel *) enet_malloc (channelCount * sizeof (ENetChannel));
if (currentPeer -> channels == NULL)
return NULL;
currentPeer -> channelCount = channelCount;
currentPeer -> state = ENET_PEER_STATE_ACKNOWLEDGING_CONNECT;
currentPeer -> connectID = command -> connect.connectID;
currentPeer -> address = host -> receivedAddress;
currentPeer -> outgoingPeerID = ENET_NET_TO_HOST_16 (command -> connect.outgoingPeerID);
currentPeer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.incomingBandwidth);
currentPeer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> connect.outgoingBandwidth);
currentPeer -> packetThrottleInterval = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleInterval);
currentPeer -> packetThrottleAcceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleAcceleration);
currentPeer -> packetThrottleDeceleration = ENET_NET_TO_HOST_32 (command -> connect.packetThrottleDeceleration);
currentPeer -> eventData = ENET_NET_TO_HOST_32 (command -> connect.data);
incomingSessionID = command -> connect.incomingSessionID == 0xFF ? currentPeer -> outgoingSessionID : command -> connect.incomingSessionID;
incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
if (incomingSessionID == currentPeer -> outgoingSessionID)
incomingSessionID = (incomingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
currentPeer -> outgoingSessionID = incomingSessionID;
outgoingSessionID = command -> connect.outgoingSessionID == 0xFF ? currentPeer -> incomingSessionID : command -> connect.outgoingSessionID;
outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
if (outgoingSessionID == currentPeer -> incomingSessionID)
outgoingSessionID = (outgoingSessionID + 1) & (ENET_PROTOCOL_HEADER_SESSION_MASK >> ENET_PROTOCOL_HEADER_SESSION_SHIFT);
currentPeer -> incomingSessionID = outgoingSessionID;
for (channel = currentPeer -> channels;
channel < & currentPeer -> channels [channelCount];
++ channel)
{
channel -> outgoingReliableSequenceNumber = 0;
channel -> outgoingUnreliableSequenceNumber = 0;
channel -> incomingReliableSequenceNumber = 0;
channel -> incomingUnreliableSequenceNumber = 0;
enet_list_clear (& channel -> incomingReliableCommands);
enet_list_clear (& channel -> incomingUnreliableCommands);
channel -> usedReliableWindows = 0;
memset (channel -> reliableWindows, 0, sizeof (channel -> reliableWindows));
}
mtu = ENET_NET_TO_HOST_32 (command -> connect.mtu);
if (mtu < ENET_PROTOCOL_MINIMUM_MTU)
mtu = ENET_PROTOCOL_MINIMUM_MTU;
else
if (mtu > ENET_PROTOCOL_MAXIMUM_MTU)
mtu = ENET_PROTOCOL_MAXIMUM_MTU;
currentPeer -> mtu = mtu;
if (host -> outgoingBandwidth == 0 &&
currentPeer -> incomingBandwidth == 0)
currentPeer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
else
if (host -> outgoingBandwidth == 0 ||
currentPeer -> incomingBandwidth == 0)
currentPeer -> windowSize = (ENET_MAX (host -> outgoingBandwidth, currentPeer -> incomingBandwidth) /
ENET_PEER_WINDOW_SIZE_SCALE) *
ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
else
currentPeer -> windowSize = (ENET_MIN (host -> outgoingBandwidth, currentPeer -> incomingBandwidth) /
ENET_PEER_WINDOW_SIZE_SCALE) *
ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
if (currentPeer -> windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE)
currentPeer -> windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
else
if (currentPeer -> windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE)
currentPeer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
if (host -> incomingBandwidth == 0)
windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
else
windowSize = (host -> incomingBandwidth / ENET_PEER_WINDOW_SIZE_SCALE) *
ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
if (windowSize > ENET_NET_TO_HOST_32 (command -> connect.windowSize))
windowSize = ENET_NET_TO_HOST_32 (command -> connect.windowSize);
if (windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE)
windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
else
if (windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE)
windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
verifyCommand.header.command = ENET_PROTOCOL_COMMAND_VERIFY_CONNECT | ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE;
verifyCommand.header.channelID = 0xFF;
verifyCommand.verifyConnect.outgoingPeerID = ENET_HOST_TO_NET_16 (currentPeer -> incomingPeerID);
verifyCommand.verifyConnect.incomingSessionID = incomingSessionID;
verifyCommand.verifyConnect.outgoingSessionID = outgoingSessionID;
verifyCommand.verifyConnect.mtu = ENET_HOST_TO_NET_16 (currentPeer -> mtu);
verifyCommand.verifyConnect.windowSize = ENET_HOST_TO_NET_32 (windowSize);
verifyCommand.verifyConnect.channelCount = ENET_HOST_TO_NET_32 (channelCount);
verifyCommand.verifyConnect.incomingBandwidth = ENET_HOST_TO_NET_32 (host -> incomingBandwidth);
verifyCommand.verifyConnect.outgoingBandwidth = ENET_HOST_TO_NET_32 (host -> outgoingBandwidth);
verifyCommand.verifyConnect.packetThrottleInterval = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleInterval);
verifyCommand.verifyConnect.packetThrottleAcceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleAcceleration);
verifyCommand.verifyConnect.packetThrottleDeceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleDeceleration);
verifyCommand.verifyConnect.connectID = currentPeer -> connectID;
enet_peer_queue_outgoing_command (currentPeer, & verifyCommand, NULL, 0, 0);
return currentPeer;
}
static int
enet_protocol_handle_send_reliable (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData)
{
ENetPacket * packet;
size_t dataLength;
if (command -> header.channelID >= peer -> channelCount ||
(peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER))
return -1;
dataLength = ENET_NET_TO_HOST_16 (command -> sendReliable.dataLength);
* currentData += dataLength;
if (* 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;
startCommand = enet_peer_queue_incoming_command (peer, & hostCommand, packet, fragmentCount);
if (startCommand == NULL)
return -1;
}
if ((startCommand -> fragments [fragmentNumber / 32] & (1 << (fragmentNumber % 32))) == 0)
{
-- startCommand -> fragmentsRemaining;
startCommand -> fragments [fragmentNumber / 32] |= (1 << (fragmentNumber % 32));
if (fragmentOffset + fragmentLength > startCommand -> packet -> dataLength)
fragmentLength = startCommand -> packet -> dataLength - fragmentOffset;
memcpy (startCommand -> packet -> data + fragmentOffset,
(enet_uint8 *) command + sizeof (ENetProtocolSendFragment),
fragmentLength);
if (startCommand -> fragmentsRemaining <= 0)
enet_peer_dispatch_incoming_reliable_commands (peer, channel);
}
return 0;
}
static int
enet_protocol_handle_send_unreliable_fragment (ENetHost * host, ENetPeer * peer, const ENetProtocol * command, enet_uint8 ** currentData)
{
enet_uint32 fragmentNumber,
fragmentCount,
fragmentOffset,
fragmentLength,
reliableSequenceNumber,
startSequenceNumber,
totalLength;
enet_uint16 reliableWindow, currentWindow;
ENetChannel * channel;
ENetListIterator currentCommand;
ENetIncomingCommand * startCommand = NULL;
if (command -> header.channelID >= peer -> channelCount ||
(peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER))
return -1;
fragmentLength = ENET_NET_TO_HOST_16 (command -> sendFragment.dataLength);
* currentData += fragmentLength;
if (* 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 (fragmentOffset >= totalLength ||
fragmentOffset + fragmentLength > totalLength ||
fragmentNumber >= fragmentCount)
return -1;
for (currentCommand = enet_list_previous (enet_list_end (& channel -> incomingUnreliableCommands));
currentCommand != enet_list_end (& channel -> incomingUnreliableCommands);
currentCommand = enet_list_previous (currentCommand))
{
ENetIncomingCommand * incomingCommand = (ENetIncomingCommand *) currentCommand;
if (reliableSequenceNumber >= channel -> incomingReliableSequenceNumber)
{
if (incomingCommand -> reliableSequenceNumber < channel -> incomingReliableSequenceNumber)
continue;
}
else
if (incomingCommand -> reliableSequenceNumber >= channel -> incomingReliableSequenceNumber)
break;
if (incomingCommand -> reliableSequenceNumber < reliableSequenceNumber)
break;
if (incomingCommand -> reliableSequenceNumber > reliableSequenceNumber)
continue;
if (incomingCommand -> unreliableSequenceNumber <= startSequenceNumber)
{
if (incomingCommand -> unreliableSequenceNumber < startSequenceNumber)
break;
if ((incomingCommand -> command.header.command & ENET_PROTOCOL_COMMAND_MASK) != ENET_PROTOCOL_COMMAND_SEND_UNRELIABLE_FRAGMENT ||
totalLength != incomingCommand -> packet -> dataLength ||
fragmentCount != incomingCommand -> fragmentCount)
return -1;
startCommand = incomingCommand;
break;
}
}
if (startCommand == NULL)
{
ENetPacket * packet = enet_packet_create (NULL, totalLength, ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT);
if (packet == NULL)
return -1;
startCommand = enet_peer_queue_incoming_command (peer, command, packet, fragmentCount);
if (startCommand == NULL)
return -1;
}
if ((startCommand -> fragments [fragmentNumber / 32] & (1 << (fragmentNumber % 32))) == 0)
{
-- startCommand -> fragmentsRemaining;
startCommand -> fragments [fragmentNumber / 32] |= (1 << (fragmentNumber % 32));
if (fragmentOffset + fragmentLength > startCommand -> packet -> dataLength)
fragmentLength = startCommand -> packet -> dataLength - fragmentOffset;
memcpy (startCommand -> packet -> data + fragmentOffset,
(enet_uint8 *) command + sizeof (ENetProtocolSendFragment),
fragmentLength);
if (startCommand -> fragmentsRemaining <= 0)
enet_peer_dispatch_incoming_unreliable_commands (peer, channel);
}
return 0;
}
static int
enet_protocol_handle_ping (ENetHost * host, ENetPeer * peer, const ENetProtocol * command)
{
return 0;
}
static int
enet_protocol_handle_bandwidth_limit (ENetHost * host, ENetPeer * peer, const ENetProtocol * command)
{
peer -> incomingBandwidth = ENET_NET_TO_HOST_32 (command -> bandwidthLimit.incomingBandwidth);
peer -> outgoingBandwidth = ENET_NET_TO_HOST_32 (command -> bandwidthLimit.outgoingBandwidth);
if (peer -> incomingBandwidth == 0 && host -> outgoingBandwidth == 0)
peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
else
peer -> windowSize = (ENET_MIN (peer -> incomingBandwidth, host -> outgoingBandwidth) /
ENET_PEER_WINDOW_SIZE_SCALE) * ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
if (peer -> windowSize < ENET_PROTOCOL_MINIMUM_WINDOW_SIZE)
peer -> windowSize = ENET_PROTOCOL_MINIMUM_WINDOW_SIZE;
else
if (peer -> windowSize > ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE)
peer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE;
return 0;
}
static int
enet_protocol_handle_throttle_configure (ENetHost * host, ENetPeer * peer, const ENetProtocol * command)
{
peer -> packetThrottleInterval = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleInterval);
peer -> packetThrottleAcceleration = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleAcceleration);
peer -> packetThrottleDeceleration = ENET_NET_TO_HOST_32 (command -> throttleConfigure.packetThrottleDeceleration);
return 0;
}
static int
enet_protocol_handle_disconnect (ENetHost * host, ENetPeer * peer, const ENetProtocol * command)
{
if (peer -> state == ENET_PEER_STATE_ZOMBIE || peer -> state == ENET_PEER_STATE_ACKNOWLEDGING_DISCONNECT)
return 0;
enet_peer_reset_queues (peer);
if (peer -> state == ENET_PEER_STATE_CONNECTION_SUCCEEDED || peer -> state == ENET_PEER_STATE_DISCONNECTING)
enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE);
else
if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER)
{
if (peer -> state == ENET_PEER_STATE_CONNECTION_PENDING) host -> recalculateBandwidthLimits = 1;
enet_peer_reset (peer);
}
else
if (command -> header.command & ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE)
peer -> state = ENET_PEER_STATE_ACKNOWLEDGING_DISCONNECT;
else
enet_protocol_dispatch_state (host, peer, ENET_PEER_STATE_ZOMBIE);
if (peer -> state != ENET_PEER_STATE_DISCONNECTED)
peer -> eventData = ENET_NET_TO_HOST_32 (command -> disconnect.data);
return 0;
}
static int
enet_protocol_handle_acknowledge (ENetHost * host, ENetEvent * event, ENetPeer * peer, const ENetProtocol * command)
{
enet_uint32 roundTripTime,
receivedSentTime,
receivedReliableSequenceNumber;
ENetProtocolCommand commandNumber;
receivedSentTime = ENET_NET_TO_HOST_16 (command -> acknowledge.receivedSentTime);
receivedSentTime |= host -> serviceTime & 0xFFFF0000;
if ((receivedSentTime & 0x8000) > (host -> serviceTime & 0x8000))
receivedSentTime -= 0x10000;
if (ENET_TIME_LESS (host -> serviceTime, receivedSentTime))
return 0;
peer -> lastReceiveTime = host -> serviceTime;
peer -> earliestTimeout = 0;
roundTripTime = ENET_TIME_DIFFERENCE (host -> serviceTime, receivedSentTime);
enet_peer_throttle (peer, roundTripTime);
peer -> roundTripTimeVariance -= peer -> roundTripTimeVariance / 4;
if (roundTripTime >= peer -> roundTripTime)
{
peer -> roundTripTime += (roundTripTime - peer -> roundTripTime) / 8;
peer -> roundTripTimeVariance += (roundTripTime - peer -> roundTripTime) / 4;
}
else
{
peer -> roundTripTime -= (peer -> roundTripTime - roundTripTime) / 8;
peer -> roundTripTimeVariance += (peer -> roundTripTime - roundTripTime) / 4;
}
if (peer -> roundTripTime < peer -> lowestRoundTripTime)
peer -> lowestRoundTripTime = peer -> roundTripTime;
if (peer -> roundTripTimeVariance > peer -> highestRoundTripTimeVariance)
peer -> highestRoundTripTimeVariance = peer -> roundTripTimeVariance;
if (peer -> packetThrottleEpoch == 0 ||
ENET_TIME_DIFFERENCE (host -> serviceTime, peer -> packetThrottleEpoch) >= peer -> packetThrottleInterval)
{
peer -> lastRoundTripTime = peer -> lowestRoundTripTime;
peer -> lastRoundTripTimeVariance = peer -> highestRoundTripTimeVariance;
peer -> lowestRoundTripTime = peer -> roundTripTime;
peer -> highestRoundTripTimeVariance = peer -> roundTripTimeVariance;
peer -> packetThrottleEpoch = host -> serviceTime;
}
receivedReliableSequenceNumber = ENET_NET_TO_HOST_16 (command -> acknowledge.receivedReliableSequenceNumber);
commandNumber = enet_protocol_remove_sent_reliable_command (peer, receivedReliableSequenceNumber, command -> header.channelID);
switch (peer -> state)
{
case ENET_PEER_STATE_ACKNOWLEDGING_CONNECT:
if (commandNumber != ENET_PROTOCOL_COMMAND_VERIFY_CONNECT)
return -1;
enet_protocol_notify_connect (host, peer, event);
break;
case ENET_PEER_STATE_DISCONNECTING:
if (commandNumber != ENET_PROTOCOL_COMMAND_DISCONNECT)
return -1;
enet_protocol_notify_disconnect (host, peer, event);
break;
case ENET_PEER_STATE_DISCONNECT_LATER:
if (enet_list_empty (& peer -> outgoingReliableCommands) &&
enet_list_empty (& peer -> outgoingUnreliableCommands) &&
enet_list_empty (& peer -> sentReliableCommands))
enet_peer_disconnect (peer, peer -> eventData);
break;
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 (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;
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:
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 -> 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) >= 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 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_WINDOW_SIZE - 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 = 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;
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)
return 1;
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) >= 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;
}
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