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Diffstat (limited to 'libs/enet/host.c')
| -rw-r--r-- | libs/enet/host.c | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/libs/enet/host.c b/libs/enet/host.c new file mode 100644 index 0000000..8bb2433 --- /dev/null +++ b/libs/enet/host.c @@ -0,0 +1,479 @@ +/** + @file host.c + @brief ENet host management functions +*/ +#define ENET_BUILDING_LIB 1 +#include <string.h> +#include <time.h> +#include "enet/enet.h" + +/** @defgroup host ENet host functions + @{ +*/ + +/** Creates a host for communicating to peers. + + @param address the address at which other peers may connect to this host. If NULL, then no peers may connect to the host. + @param peerCount the maximum number of peers that should be allocated for the host. + @param channelLimit the maximum number of channels allowed; if 0, then this is equivalent to ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT + @param incomingBandwidth downstream bandwidth of the host in bytes/second; if 0, ENet will assume unlimited bandwidth. + @param outgoingBandwidth upstream bandwidth of the host in bytes/second; if 0, ENet will assume unlimited bandwidth. + + @returns the host on success and NULL on failure + + @remarks ENet will strategically drop packets on specific sides of a connection between hosts + to ensure the host's bandwidth is not overwhelmed. The bandwidth parameters also determine + the window size of a connection which limits the amount of reliable packets that may be in transit + at any given time. +*/ +ENetHost * +enet_host_create (const ENetAddress * address, size_t peerCount, size_t channelLimit, enet_uint32 incomingBandwidth, enet_uint32 outgoingBandwidth) +{ + ENetHost * host; + ENetPeer * currentPeer; + + if (peerCount > ENET_PROTOCOL_MAXIMUM_PEER_ID) + return NULL; + + host = (ENetHost *) enet_malloc (sizeof (ENetHost)); + if (host == NULL) + return NULL; + + host -> peers = (ENetPeer *) enet_malloc (peerCount * sizeof (ENetPeer)); + if (host -> peers == NULL) + { + enet_free (host); + + return NULL; + } + memset (host -> peers, 0, peerCount * sizeof (ENetPeer)); + + host -> socket = enet_socket_create (ENET_SOCKET_TYPE_DATAGRAM); + if (host -> socket == ENET_SOCKET_NULL || (address != NULL && enet_socket_bind (host -> socket, address) < 0)) + { + if (host -> socket != ENET_SOCKET_NULL) + enet_socket_destroy (host -> socket); + + enet_free (host -> peers); + enet_free (host); + + return NULL; + } + + enet_socket_set_option (host -> socket, ENET_SOCKOPT_NONBLOCK, 1); + enet_socket_set_option (host -> socket, ENET_SOCKOPT_BROADCAST, 1); + enet_socket_set_option (host -> socket, ENET_SOCKOPT_RCVBUF, ENET_HOST_RECEIVE_BUFFER_SIZE); + enet_socket_set_option (host -> socket, ENET_SOCKOPT_SNDBUF, ENET_HOST_SEND_BUFFER_SIZE); + + if (address != NULL) + host -> address = * address; + + if (! channelLimit || channelLimit > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT) + channelLimit = ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT; + else + if (channelLimit < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT) + channelLimit = ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT; + + host -> randomSeed = (enet_uint32) time(NULL) + (enet_uint32) (size_t) host; + host -> randomSeed = (host -> randomSeed << 16) | (host -> randomSeed >> 16); + host -> channelLimit = channelLimit; + host -> incomingBandwidth = incomingBandwidth; + host -> outgoingBandwidth = outgoingBandwidth; + host -> bandwidthThrottleEpoch = 0; + host -> recalculateBandwidthLimits = 0; + host -> mtu = ENET_HOST_DEFAULT_MTU; + host -> peerCount = peerCount; + host -> commandCount = 0; + host -> bufferCount = 0; + host -> checksum = NULL; + host -> receivedAddress.host = ENET_HOST_ANY; + host -> receivedAddress.port = 0; + host -> receivedData = NULL; + host -> receivedDataLength = 0; + + host -> totalSentData = 0; + host -> totalSentPackets = 0; + host -> totalReceivedData = 0; + host -> totalReceivedPackets = 0; + + host -> compressor.context = NULL; + host -> compressor.compress = NULL; + host -> compressor.decompress = NULL; + host -> compressor.destroy = NULL; + + enet_list_clear (& host -> dispatchQueue); + + for (currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + currentPeer -> host = host; + currentPeer -> incomingPeerID = currentPeer - host -> peers; + currentPeer -> outgoingSessionID = currentPeer -> incomingSessionID = 0xFF; + currentPeer -> data = NULL; + + enet_list_clear (& currentPeer -> acknowledgements); + enet_list_clear (& currentPeer -> sentReliableCommands); + enet_list_clear (& currentPeer -> sentUnreliableCommands); + enet_list_clear (& currentPeer -> outgoingReliableCommands); + enet_list_clear (& currentPeer -> outgoingUnreliableCommands); + enet_list_clear (& currentPeer -> dispatchedCommands); + + enet_peer_reset (currentPeer); + } + + return host; +} + +/** Destroys the host and all resources associated with it. + @param host pointer to the host to destroy +*/ +void +enet_host_destroy (ENetHost * host) +{ + ENetPeer * currentPeer; + + enet_socket_destroy (host -> socket); + + for (currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + enet_peer_reset (currentPeer); + } + + if (host -> compressor.context != NULL && host -> compressor.destroy) + (* host -> compressor.destroy) (host -> compressor.context); + + enet_free (host -> peers); + enet_free (host); +} + +/** Initiates a connection to a foreign host. + @param host host seeking the connection + @param address destination for the connection + @param channelCount number of channels to allocate + @param data user data supplied to the receiving host + @returns a peer representing the foreign host on success, NULL on failure + @remarks The peer returned will have not completed the connection until enet_host_service() + notifies of an ENET_EVENT_TYPE_CONNECT event for the peer. +*/ +ENetPeer * +enet_host_connect (ENetHost * host, const ENetAddress * address, size_t channelCount, enet_uint32 data) +{ + ENetPeer * currentPeer; + ENetChannel * channel; + ENetProtocol command; + + if (channelCount < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT) + channelCount = ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT; + else + if (channelCount > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT) + channelCount = ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT; + + 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; + + currentPeer -> channels = (ENetChannel *) enet_malloc (channelCount * sizeof (ENetChannel)); + if (currentPeer -> channels == NULL) + return NULL; + currentPeer -> channelCount = channelCount; + currentPeer -> state = ENET_PEER_STATE_CONNECTING; + currentPeer -> address = * address; + currentPeer -> connectID = ++ host -> randomSeed; + + if (host -> outgoingBandwidth == 0) + currentPeer -> windowSize = ENET_PROTOCOL_MAXIMUM_WINDOW_SIZE; + else + currentPeer -> windowSize = (host -> outgoingBandwidth / + 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; + + for (channel = currentPeer -> channels; + channel < & currentPeer -> channels [channelCount]; + ++ channel) + { + channel -> outgoingReliableSequenceNumber = 0; + channel -> outgoingUnreliableSequenceNumber = 0; + channel -> incomingReliableSequenceNumber = 0; + + enet_list_clear (& channel -> incomingReliableCommands); + enet_list_clear (& channel -> incomingUnreliableCommands); + + channel -> usedReliableWindows = 0; + memset (channel -> reliableWindows, 0, sizeof (channel -> reliableWindows)); + } + + command.header.command = ENET_PROTOCOL_COMMAND_CONNECT | ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE; + command.header.channelID = 0xFF; + command.connect.outgoingPeerID = ENET_HOST_TO_NET_16 (currentPeer -> incomingPeerID); + command.connect.incomingSessionID = currentPeer -> incomingSessionID; + command.connect.outgoingSessionID = currentPeer -> outgoingSessionID; + command.connect.mtu = ENET_HOST_TO_NET_32 (currentPeer -> mtu); + command.connect.windowSize = ENET_HOST_TO_NET_32 (currentPeer -> windowSize); + command.connect.channelCount = ENET_HOST_TO_NET_32 (channelCount); + command.connect.incomingBandwidth = ENET_HOST_TO_NET_32 (host -> incomingBandwidth); + command.connect.outgoingBandwidth = ENET_HOST_TO_NET_32 (host -> outgoingBandwidth); + command.connect.packetThrottleInterval = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleInterval); + command.connect.packetThrottleAcceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleAcceleration); + command.connect.packetThrottleDeceleration = ENET_HOST_TO_NET_32 (currentPeer -> packetThrottleDeceleration); + command.connect.connectID = currentPeer -> connectID; + command.connect.data = ENET_HOST_TO_NET_32 (data); + + enet_peer_queue_outgoing_command (currentPeer, & command, NULL, 0, 0); + + return currentPeer; +} + +/** Queues a packet to be sent to all peers associated with the host. + @param host host on which to broadcast the packet + @param channelID channel on which to broadcast + @param packet packet to broadcast +*/ +void +enet_host_broadcast (ENetHost * host, enet_uint8 channelID, ENetPacket * packet) +{ + ENetPeer * currentPeer; + + for (currentPeer = host -> peers; + currentPeer < & host -> peers [host -> peerCount]; + ++ currentPeer) + { + if (currentPeer -> state != ENET_PEER_STATE_CONNECTED) + continue; + + enet_peer_send (currentPeer, channelID, packet); + } + + if (packet -> referenceCount == 0) + enet_packet_destroy (packet); +} + +/** Sets the packet compressor the host should use to compress and decompress packets. + @param host host to enable or disable compression for + @param compressor callbacks for for the packet compressor; if NULL, then compression is disabled +*/ +void +enet_host_compress (ENetHost * host, const ENetCompressor * compressor) +{ + if (host -> compressor.context != NULL && host -> compressor.destroy) + (* host -> compressor.destroy) (host -> compressor.context); + + if (compressor) + host -> compressor = * compressor; + else + host -> compressor.context = NULL; +} + +/** Limits the maximum allowed channels of future incoming connections. + @param host host to limit + @param channelLimit the maximum number of channels allowed; if 0, then this is equivalent to ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT +*/ +void +enet_host_channel_limit (ENetHost * host, size_t channelLimit) +{ + if (! channelLimit || channelLimit > ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT) + channelLimit = ENET_PROTOCOL_MAXIMUM_CHANNEL_COUNT; + else + if (channelLimit < ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT) + channelLimit = ENET_PROTOCOL_MINIMUM_CHANNEL_COUNT; + + host -> channelLimit = channelLimit; +} + + +/** Adjusts the bandwidth limits of a host. + @param host host to adjust + @param incomingBandwidth new incoming bandwidth + @param outgoingBandwidth new outgoing bandwidth + @remarks the incoming and outgoing bandwidth parameters are identical in function to those + specified in enet_host_create(). +*/ +void +enet_host_bandwidth_limit (ENetHost * host, enet_uint32 incomingBandwidth, enet_uint32 outgoingBandwidth) +{ + host -> incomingBandwidth = incomingBandwidth; + host -> outgoingBandwidth = outgoingBandwidth; + host -> recalculateBandwidthLimits = 1; +} + +void +enet_host_bandwidth_throttle (ENetHost * host) +{ + enet_uint32 timeCurrent = enet_time_get (), + elapsedTime = timeCurrent - host -> bandwidthThrottleEpoch, + peersTotal = 0, + dataTotal = 0, + peersRemaining, + bandwidth, + throttle = 0, + bandwidthLimit = 0; + int needsAdjustment; + ENetPeer * peer; + ENetProtocol command; + + if (elapsedTime < ENET_HOST_BANDWIDTH_THROTTLE_INTERVAL) + return; + + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) + continue; + + ++ peersTotal; + dataTotal += peer -> outgoingDataTotal; + } + + if (peersTotal == 0) + return; + + peersRemaining = peersTotal; + needsAdjustment = 1; + + if (host -> outgoingBandwidth == 0) + bandwidth = ~0; + else + bandwidth = (host -> outgoingBandwidth * elapsedTime) / 1000; + + while (peersRemaining > 0 && needsAdjustment != 0) + { + needsAdjustment = 0; + + if (dataTotal < bandwidth) + throttle = ENET_PEER_PACKET_THROTTLE_SCALE; + else + throttle = (bandwidth * ENET_PEER_PACKET_THROTTLE_SCALE) / dataTotal; + + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + enet_uint32 peerBandwidth; + + if ((peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) || + peer -> incomingBandwidth == 0 || + peer -> outgoingBandwidthThrottleEpoch == timeCurrent) + continue; + + peerBandwidth = (peer -> incomingBandwidth * elapsedTime) / 1000; + if ((throttle * peer -> outgoingDataTotal) / ENET_PEER_PACKET_THROTTLE_SCALE <= peerBandwidth) + continue; + + peer -> packetThrottleLimit = (peerBandwidth * + ENET_PEER_PACKET_THROTTLE_SCALE) / peer -> outgoingDataTotal; + + if (peer -> packetThrottleLimit == 0) + peer -> packetThrottleLimit = 1; + + if (peer -> packetThrottle > peer -> packetThrottleLimit) + peer -> packetThrottle = peer -> packetThrottleLimit; + + peer -> outgoingBandwidthThrottleEpoch = timeCurrent; + + + needsAdjustment = 1; + -- peersRemaining; + bandwidth -= peerBandwidth; + dataTotal -= peerBandwidth; + } + } + + if (peersRemaining > 0) + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + if ((peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) || + peer -> outgoingBandwidthThrottleEpoch == timeCurrent) + continue; + + peer -> packetThrottleLimit = throttle; + + if (peer -> packetThrottle > peer -> packetThrottleLimit) + peer -> packetThrottle = peer -> packetThrottleLimit; + } + + if (host -> recalculateBandwidthLimits) + { + host -> recalculateBandwidthLimits = 0; + + peersRemaining = peersTotal; + bandwidth = host -> incomingBandwidth; + needsAdjustment = 1; + + if (bandwidth == 0) + bandwidthLimit = 0; + else + while (peersRemaining > 0 && needsAdjustment != 0) + { + needsAdjustment = 0; + bandwidthLimit = bandwidth / peersRemaining; + + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + if ((peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) || + peer -> incomingBandwidthThrottleEpoch == timeCurrent) + continue; + + if (peer -> outgoingBandwidth > 0 && + peer -> outgoingBandwidth >= bandwidthLimit) + continue; + + peer -> incomingBandwidthThrottleEpoch = timeCurrent; + + needsAdjustment = 1; + -- peersRemaining; + bandwidth -= peer -> outgoingBandwidth; + } + } + + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + if (peer -> state != ENET_PEER_STATE_CONNECTED && peer -> state != ENET_PEER_STATE_DISCONNECT_LATER) + continue; + + command.header.command = ENET_PROTOCOL_COMMAND_BANDWIDTH_LIMIT | ENET_PROTOCOL_COMMAND_FLAG_ACKNOWLEDGE; + command.header.channelID = 0xFF; + command.bandwidthLimit.outgoingBandwidth = ENET_HOST_TO_NET_32 (host -> outgoingBandwidth); + + if (peer -> incomingBandwidthThrottleEpoch == timeCurrent) + command.bandwidthLimit.incomingBandwidth = ENET_HOST_TO_NET_32 (peer -> outgoingBandwidth); + else + command.bandwidthLimit.incomingBandwidth = ENET_HOST_TO_NET_32 (bandwidthLimit); + + enet_peer_queue_outgoing_command (peer, & command, NULL, 0, 0); + } + } + + host -> bandwidthThrottleEpoch = timeCurrent; + + for (peer = host -> peers; + peer < & host -> peers [host -> peerCount]; + ++ peer) + { + peer -> incomingDataTotal = 0; + peer -> outgoingDataTotal = 0; + } +} + +/** @} */ |