Messaging System
[Networking]

Collaboration diagram for Messaging System:

A system used to send data, receive acknowledgment of sent data, and responding to acknowledgments or lack thereof. More...


Files
file	message.c
	Implementation of the Messaging System.
file	message.h
	Interface to the Messaging System.
Data Structures
struct	MsgDescr_t
	Describes a message, including who should receive it and data needed to handle acknowledgments. More...
struct	NetBuffer_t
	The buffer type used to store messages sent and received over the network. More...
Defines
#define	DESTMAPLEN bitarraylen(MAX_PLAYERS, DESTMAPTYPE)
	The number of elements in the array MsgDescr::destMap.
#define	DESTMAPTYPE Uint16
	The data type used for MsgDescr::destMap.
#define	GetDestMapFlag(id) bitflag(id, DESTMAPTYPE)
	Returns the bit flag that indicates the given client in the MsgDescr::destMap array at the correct index (see GetDestMapIndex()).
#define	GetDestMapIndex(id) bitindex(id, DESTMAPTYPE)
	Returns the index to the MsgDescr::destMap array that contains the flag for the given client.
#define	MSG_MAX_SIZE 510
	The maximum size of a message in bytes.
#define	SetDestToAll(msg)
	Marks a message as being destined to all clients.
Typedefs
typedef void(*)	AcknowledgeMsg (MsgDescr *descr, int cid)
	The function prototype used to react to the recipient acknowledging a message.
typedef Bool(*)	ApproveSendMsg (MsgDescr *descr, int cid)
	Approves sending a message to a given recipient.
typedef void(*)	ConstructMsg (MsgDescr *descr)
	The function prototype used to construct the message in a buffer.
typedef void(*)	FailMsg (MsgDescr descr, ClientData client)
	The function prototype used to react to a recipient that did not acknowledge a message, or if an error occured when trying to send a message.
typedef Bool(*)	HandleMsg (SocketAddr origin, NetBuffer buffer, Uint8 *clientId, Uint16 messageId)
	The function prototype used to process incomming messages.
typedef MsgDescr_t	MsgDescr
typedef NetBuffer_t	NetBuffer
Enumerations
enum	{ MSG_TYPE_ACK, MSG_TYPE_CONN_REQ, MSG_TYPE_CONN_DENY, MSG_TYPE_CONN_ACCEPT, MSG_TYPE_CONN_DISCONN, MSG_TYPE_OPTION, MSG_TYPE_OBSTACLE, MSG_TYPE_SPAWN, MSG_TYPE_GOAL, MSG_TYPE_GAME_START, MSG_TYPE_GAME_OVER, MSG_TYPE_SCORE = MSG_TYPE_GOAL + 1, MSG_TYPE_PLAYER_UPDATE, MSG_TYPE_PLAYER_SPWAN, MSG_TYPE_MAX }
	The message type identifiers that are always sent as the first byte of every message. More...
Functions
Bool	AddMessage (MsgDescr *msg)
	Adds a new message to the messaging system and sends it out immediately.
void	BufferFree (NetBuffer *buff)
	Returns a no longer used network buffer to the queue of available buffers.
NetBuffer *	BufferNew ()
	Obtains a new message buffer from the internal list of buffers.
void	BufferVecDestr (void *buff)
	A Vector destructor that returns a no longer used network buffer to the queue of available buffers.
void	CancelAllMessages ()
	Cancels all in-flight messages effectively killing communication with the remote end(s).
int	GetNumOutgoingMessages ()
	Returns the number of messages that have been sent but not acknowledged.
void	MessageFree (MsgDescr *msg)
	Returns an unused message to the queue of available messages, or deallocates it if the maximum number of messages are in the available queue (MAX_MESSAGES).
Bool	MessageInit ()
	Initializes the network messaging system.
MsgDescr *	MessageNew ()
	Gets a new uninitialized message so that it can be put to use describing a new message.
void	MessageUninit ()
	Uninitializes the network messaging system.
void	MsgFailDisconnect (MsgDescr descr, ClientData client)
	A message failure function that disconnects from the remote end in the most reliable manner possible.
void	MsgFailDropConnection (MsgDescr descr, ClientData client)
	A message failure function that immediately terminates all communication.
void	ProcessNetworkMessages ()
	Handles all network I/O for the client or server.
Bool	ReceiveMessages ()
	Handles all incomming messages.
static Bool	Send (MsgDescr *msg, Bool inSys)
	Transmits the given message to the other end(s) and/or cancels the message.
Bool	SendDisconnectMessage (Uint8 id)
	Sends a disconnect message (see MSG_TYPE_CONN_DISCONN and the data format) indicating the specified client is leaving the game.
void	ServiceMessages ()
	Services the outgoing messages that are already in the system.
Bool	ValidateClient (SocketAddr *origin, Uint8 clientId)
	Determines if incomming client data came from a valid source.
Bool	ValidateServer (SocketAddr *origin)
	Determines if the inomming server data came from the server that is running the game, and if this process is a client.

Detailed Description

A system used to send data, receive acknowledgment of sent data, and responding to acknowledgments or lack thereof.

When messages are sent but not yet acknowledged, they are in-flight.
All message descriptors (MsgDescr) are dynamically allocated.
Pointers to message descriptors for in-flight messages are stored in a priority queue by resend time, and in an AA-Tree by message ID.
Pointers to unused but allocated message descriptors are stored in a list. If the list has the maximum number of descriptors, then freed descriptots are deallocated. If the list is empty, new descriptors are allocated on demand.
Pointers to unused buffers are stored in a list. There is no list of buffers that are in use, but the message descriptors contain a pointer to the buffer it owns.

Diagram of message data relationships:

Bug:: In the above dot digraph, all the links must not use the Javadoc style @ symbol to denote tags, although the Javadoc style is valid everywhere else.

Bug:: It would be nice to add line breaks to the labels in the above graph, but Doxygen wrecks the line break tags that the dot tool recognizes.

In the diagram, arrows point in the same direction as the actual pointer. Dashed lines indicate how an item's state can change at run-time.

The following macros affect how the message system operates:

MSG_INF_TRIES -- Messages never leave the system unless all destinations acknowledge the message, or an error occured while attempting to send. This can cause problems when clients disconnect followed by other clients connecting to the server. It is intended to assist with debugging client-server communication. When a message's MsgDescr::triesLeft value drops to zero, its value will not be further decerased and the resend interval will be set to a constant 16 seconds.

Warning:: The messaging system is not thread safe.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. Or visit their website at: http://www.gnu.org/

Author:: Jeff Jackowski

Define Documentation

#define DESTMAPLEN bitarraylen(MAX_PLAYERS, DESTMAPTYPE)

The number of elements in the array MsgDescr::destMap.

Definition at line 309 of file message.h.

Referenced by HandleAck(), MessageNew(), Send(), and ServiceGameConfig().

#define DESTMAPTYPE Uint16

The data type used for MsgDescr::destMap.

Definition at line 304 of file message.h.

Referenced by HandleAck(), and Send().

#define GetDestMapFlag ( id ) bitflag(id, DESTMAPTYPE)

Returns the bit flag that indicates the given client in the MsgDescr::destMap array at the correct index (see GetDestMapIndex()).

Parameters:

The ID of the client who's bit flag is sought.

Returns:: The bit flag. Only the client's bit is set.

Author:: Jeff Jackowski

Definition at line 327 of file message.h.

Referenced by AddToConfigList(), HandleAck(), and RemoveFromConfigList().

#define GetDestMapIndex ( id ) bitindex(id, DESTMAPTYPE)

Returns the index to the MsgDescr::destMap array that contains the flag for the given client.

Parameters:

The ID of the client who's array position is sought.

Returns:: The index.

Author:: Jeff Jackowski

Definition at line 318 of file message.h.

Referenced by AddToConfigList(), HandleAck(), and RemoveFromConfigList().

#define MSG_MAX_SIZE 510

The maximum size of a message in bytes.

See NetBuffer for details on appropriate values.

Definition at line 199 of file message.h.

Referenced by AppendPlayerData(), MakeAreaBuffers(), and ReceiveMessages().

#define SetDestToAll ( msg )

Value:

{                                                                \
    int loop;                                                    \
    DESTMAPTYPE *map = &((msg)->destMap[0]);                     \
    *map = ~0;                                                   \
    for (loop = DESTMAPLEN - 1; loop > 0; loop--) *(++map) = ~0; \
}

Marks a message as being destined to all clients.

Parameters:

msg

A pointer to the message descriptor to modify.

Author:: Jeff Jackowski

Definition at line 334 of file message.h.

Referenced by AppendPlayerData(), SendDisconnectMessage(), and SendScoreUpdate().

Typedef Documentation

typedef void(*) AcknowledgeMsg(MsgDescr *descr, int cid)

The function prototype used to react to the recipient acknowledging a message.

After this function is called, the bit corresponding to the acknowledging host in MsgDescr::destMap will be cleared.

Precondition:: The client has been validated with ValidateClient().

Parameters:

	descr	The message descriptor data.
	cid	The client's ID.

Definition at line 256 of file message.h.

typedef Bool(*) ApproveSendMsg(MsgDescr *descr, int cid)

Approves sending a message to a given recipient.

If approval is not given, the recipient will be removed from the message's destination list and the corresponding FailMsg function will not be called.

Parameters:

	descr	The message descriptor data for the message to approve.
	cid	The destination client ID.

Returns:: True if the message should be sent to the indicated player.

Definition at line 299 of file message.h.

typedef void(*) ConstructMsg(MsgDescr *descr)

The function prototype used to construct the message in a buffer.

When the function is called for the first time for a given message, the MsgDescr::inflight flag will be cleared; all subsequent calls will see the flag set. The system is responsible for transmitting the message to all the recipiants.

Deprecated:

Parameters:

descr

The message descriptor data.

Definition at line 229 of file message.h.

typedef void(*) FailMsg(MsgDescr *descr, ClientData *client)

The function prototype used to react to a recipient that did not acknowledge a message, or if an error occured when trying to send a message.

Parameters:

	descr	The message descriptor data.
	client	A pointer to the client data that failed to respond, or NULL if this process is a client.

Definition at line 265 of file message.h.

typedef Bool(*) HandleMsg(SocketAddr *origin, NetBuffer *buffer, Uint8 *clientId, Uint16 messageId)

The function prototype used to process incomming messages.

Parameters:

	origin	The originating address of the message as reported by recvfrom().
	buffer	The buffer that contains the whole message including the message type byte.
	clientId	A pointer used to return the ID of the client sending the message. This must be set for the message to be acknowledged by the server. For client side operation, this value should always be zero.
	messageId	The message ID that this function is processing. This is useful to prevent re-updating player data that has been received twice because the server didn't get an acknowledgment in time. Some message types lack a message ID; see the message formats for which ones.

Returns:: True to acknowledge the message, false otherwise.

Definition at line 654 of file message.h.

typedef struct MsgDescr_t MsgDescr

Definition at line 124 of file message.h.

typedef struct NetBuffer_t NetBuffer

Definition at line 218 of file message.h.

Enumeration Type Documentation

anonymous enum

The message type identifiers that are always sent as the first byte of every message.

The ID's must be put in the following order to simplify ReceiveMessages():

Messages that lack an ID
Messages that include an ID.

Enumerator:

MSG_TYPE_ACK	Message acknowledgment.
MSG_TYPE_CONN_REQ	Connection request; see design and message format.
MSG_TYPE_CONN_DENY	Connection denial.
MSG_TYPE_CONN_ACCEPT	Connection acceptance; see design and message format.
MSG_TYPE_CONN_DISCONN	Disconnection notice. This can be sent by client and server.
MSG_TYPE_OPTION	Game configuration options; only sent by the server.
MSG_TYPE_OBSTACLE	A set of obstacle data; only sent by the server.
MSG_TYPE_SPAWN	A set of spawn areas; only sent by the server.
MSG_TYPE_GOAL	A set of goal areas for CTF; only sent by the server.
MSG_TYPE_GAME_START	Notice that the game is about to begin.
MSG_TYPE_GAME_OVER	Notice that the game has concluded.
MSG_TYPE_SCORE	An update to the scores of the teams.
MSG_TYPE_PLAYER_UPDATE	Contains updated state data for multiple players.
MSG_TYPE_PLAYER_SPWAN	A request from a player to spwan in the game.
MSG_TYPE_MAX

Definition at line 133 of file message.h.

Function Documentation

Bool AddMessage ( MsgDescr * msg )

Adds a new message to the messaging system and sends it out immediately.

The system will handle acknowledgments and re-transmissions as needed, and will assume the responsibility of deallocating the message.

Flowchart:

Parameters:

msg

The message to add to the system. The pointer should have been returned by a previous call to MessageNew(). A message can only be added once, after which it will represent the transmission state of the message.

Returns:: True on success, false if the message failed to send. On failure, the message is deallocated.

Author:: Jeff Jackowski

Definition at line 654 of file message.c.

References AATreeAdd(), MsgDescr_t::buffer, AANode_t::data, NetBuffer_t::data, MsgDescr_t::destMap, MsgDescr_t::doNotAddId, FALSE, inflightId, inflightTime, NetBuffer_t::length, MSG_WRITE_16C, MsgDescr_t::msgId, NETSTATE_CLIENT, NETSTATE_SERVER, networkState, nextMessageId, Send(), MsgDescr_t::triesLeft, TRUE, and Vector_t::VectorHeapPush().

Referenced by AppendPlayerData(), GameInit(), GameRun(), SendDisconnectMessage(), SendScoreUpdate(), SendSpawnRequest(), and ServiceGameConfig().

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void BufferFree ( NetBuffer * buff )

Returns a no longer used network buffer to the queue of available buffers.

When the macro MSG_PTR_CHK is defined, the process will fail on an assert if the given buffer is already in the available buffer list.

Parameters:

buff

The buffer to reclaim.

Author:: Jeff Jackowski

Definition at line 273 of file message.c.

References Vector_t::array, buffers, Vector_t::items, MAX_BUFFERS, and Vector_t::VectorPush().

Referenced by BufferVecDestr(), MakeAreaBuffers(), MakeBuffers(), MessageFree(), MsgDescrDestructor(), and Send().

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NetBuffer* BufferNew ( )

Obtains a new message buffer from the internal list of buffers.

Intended to allow a buffer to be added to a message prior to passing its descriptor to AddMessage() rather than use a message constructor function (MsgDescr::constrFunc). For this to work, do the following:

Set MsgDescr::buffer to the non-NULL return value of this function.
Put the desired data in the buffer.
Set MsgDescr::buffer::length to the length in bytes of the message in the buffer.
Set the MsgDescr::buffLifeMsg flag.

Returns:: The address of the buffer, or NULL if no buffers were available and a new buffer could not be allocated. The new buffer's NetBuffer::length field will be initialized to zero.

Author:: Jeff Jackowski.

Definition at line 247 of file message.c.

References buffers, NetBuffer_t::length, and Vector_t::VectorLast.

Referenced by AppendPlayerData(), MakeAreaBuffers(), MakeBuffers(), SendDisconnectMessage(), SendScoreUpdate(), and SendSpawnRequest().

void BufferVecDestr ( void * buff )

A Vector destructor that returns a no longer used network buffer to the queue of available buffers.

Parameters:

buff

A double pointer to the NetBuffer to reclaim.

Warning:: The parameter is a single pointer to fit the Vector interface for a DestructorOp. The function really expects a double pointer. Since the available buffer vector stores pointers, the vector code will pass in a pointer into the list where a pointer is stored, so a double pointer is correct.

Author:: Jeff Jackowski

Definition at line 296 of file message.c.

References BufferFree().

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void CancelAllMessages ( )

Cancels all in-flight messages effectively killing communication with the remote end(s).

Prepares the messaging system for use with another host. There is no need to call this function if the message system is about to be uninitialized with a call to MessageUninit().

Author:: Jeff Jackowski

Definition at line 162 of file message.c.

References AA_ROOT_NODE, AATreeDestroy(), Vector_t::destructOp, inflightId, inflightTime, MsgDescrDestructor(), and Vector_t::VectorClear().

Referenced by MessageCliToSrv(), MessageSrvToCli(), NetDisconnect(), and NetUninit().

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int GetNumOutgoingMessages ( )

Returns the number of messages that have been sent but not acknowledged.

Returns:: The number of messages.

Author:: Jeff Jackowski

Definition at line 177 of file message.c.

References inflightTime, and Vector_t::items.

Referenced by Disconnect().

void MessageFree ( MsgDescr * msg )

Returns an unused message to the queue of available messages, or deallocates it if the maximum number of messages are in the available queue (MAX_MESSAGES).

When the macro MSG_PTR_CHK is defined, the process will fail on an assert if the given message is already in the available message list.

Warning:: Do not call this on messages passed to AddMessage().

Precondition:: The message is not referenced in either the ID sorted tree (inflightId) or the resend time sorted priority queue (inflightTime).

Returns:: msg The unused message.

Author:: Jeff Jackowski

Definition at line 217 of file message.c.

References Vector_t::array, available, MsgDescr_t::buffer, BufferFree(), MsgDescr_t::buffLifeUnmanaged, Vector_t::items, MAX_MESSAGES, and Vector_t::VectorPush().

Referenced by AppendPlayerData(), Send(), SendDisconnectMessage(), SendScoreUpdate(), and SendSpawnRequest().

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Bool MessageInit ( )

Initializes the network messaging system.

Returns:: True if the operation succeeded.

Author:: Jeff Jackowski

Definition at line 1603 of file message.c.

References available, buffers, Vector_t::destructOp, FALSE, GenericPointerFree(), inflightTime, INIT_BUFFERS, INIT_MESSAGES, Vector_t::itemSize, Vector_t::lessOp, MIN_POINTERS, Vector_t::minSize, MSG_ACK_SIZE, TimeCompare(), TRUE, Vector_t::VectorAdd(), and Vector_t::VectorInit().

Referenced by NetInit(), and NetInitSrv().

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MsgDescr* MessageNew ( )

Gets a new uninitialized message so that it can be put to use describing a new message.

Postcondition:

The resulting message will have default values for:

The resend interval (MsgDescr::interval), set to INIT_RESEND.
The remaining tries (MsgDescr::triesLeft), set to INIT_TRIES.
The option flags (MsgDescr::flags), set to zero.

Returns:: A pointer to the message data, or NULL if there is inadequate memory.

Author:: Jeff Jackowski

Todo:: Set the initial resend time to twice the average two-way latency of network commincations as determined by the time sync operation with some constant minimum (32ms?).

Definition at line 181 of file message.c.

References available, MsgDescr_t::destMap, DESTMAPLEN, MsgDescr_t::flags, INIT_RESEND, INIT_TRIES, MsgDescr_t::interval, Vector_t::items, MsgDescr_t::triesLeft, and Vector_t::VectorLast.

Referenced by AppendPlayerData(), SendDisconnectMessage(), SendScoreUpdate(), SendSpawnRequest(), and ServiceGameConfig().

void MessageUninit ( )

Uninitializes the network messaging system.

Author:: Jeff Jackowski

Definition at line 1647 of file message.c.

References AA_ROOT_NODE, AATreeDestroy(), available, buffers, Vector_t::destructOp, inflightId, inflightTime, MsgDescrDestructor(), and Vector_t::VectorDestroy().

Referenced by NetUninit().

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void MsgFailDisconnect	(	MsgDescr *	descr,
		ClientData *	client
	)

A message failure function that disconnects from the remote end in the most reliable manner possible.

It sends out the disconnect message to all possible destinations. Because a failure has occured, the disconnect message may not be received.

Parameters:

	descr	The message descriptor data.
	client	A pointer to the client data that failed to respond, or NULL if this process is a client.

Author:: Jeff Jackowski

Definition at line 1244 of file message.c.

References ClientData_t::active, ClientData_t::cid, ClientData_t::contact, ClientData_t::disconn, ClientData_t::disconnTime, FALSE, localPlayer, MsgDescr_t::msgId, NETSTATE_CLIDISCONN, NETSTATE_CLIENT, NETSTATE_RCVCFG, NETSTATE_SERVER, networkState, players, RemoveFromConfigList(), RemovePlayer(), SendDisconnectMessage(), and TRUE.

Referenced by AppendPlayerData(), and SendScoreUpdate().

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void MsgFailDropConnection	(	MsgDescr *	descr,
		ClientData *	client
	)

A message failure function that immediately terminates all communication.

It does not send out a disconnect message unless it is on the server and the message is not a disconnect message or the failed client is the one specified in the disconnect message.

Parameters:

	descr	The message descriptor data.
	client	A pointer to the client data that failed to respond, or NULL if this process is a client.

Author:: Jeff Jackowski

Definition at line 1180 of file message.c.

References MsgDescr_t::buffer, ClientData_t::cid, CloseSocket, NetBuffer_t::data, Player_t::flags, ClientData_t::flags, NetBuffer_t::length, MSG_TYPE_CONN_DISCONN, NETSTATE_CLIDISCONN, NETSTATE_CLIENT, NETSTATE_INIT, NETSTATE_RCVCFG, NETSTATE_SERVER, networkState, players, RemoveFromConfigList(), SendDisconnectMessage(), and sock.

Referenced by SendDisconnectMessage(), and SendSpawnRequest().

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void ProcessNetworkMessages ( )

Handles all network I/O for the client or server.

Receives incomming messages, services outgoing messages, and updates player data. If running as a server, also services the game configuration messages.

Author:: Jeff Jackowski

Definition at line 1708 of file message.c.

References frameTime, NETSTATE_RCVCFG, NETSTATE_SERVER, networkState, ReceiveMessages(), ServiceGameConfig(), ServiceMessages(), and UpdatePlayers().

Referenced by BfldErrRun(), GameRun(), MenuRun(), and SplashRun().

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Bool ReceiveMessages ( )

Handles all incomming messages.

Returns:: True if successful, false on network error.

Author:: Jeff Jackowski

Definition at line 1485 of file message.c.

References SocketAddr_t::addr, NetBuffer_t::data, FALSE, GetNetErrorString(), GetNetErrorVal, inbuff, NetBuffer_t::length, SocketAddr_t::length, MAX_PLAYERS, MSG_ACK_SIZE, MSG_MAX_ACK, MSG_MAX_SIZE, MSG_READ_16C, MSG_TYPE_CONN_ACCEPT, MSG_TYPE_MAX, MSG_WRITE_16C, NETSTATE_CLIENT, NETSTATE_SERVER, NETSTATE_SRVDISCONN, networkState, rounddivup, SendAck(), sock, and TRUE.

Referenced by Disconnect(), DiscoverConnectServer(), and ProcessNetworkMessages().

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static Bool Send	(	MsgDescr *	msg,
		Bool	inSys
	)			`[static]`

Transmits the given message to the other end(s) and/or cancels the message.

For internal use only.

Precondition:: The message is not in the inflightTime priority queue, but is in the inflightId tree.

Flowchart:

Todo:: Update the flowchart. Messages are now constructed in a buffer just before sending them the first time rather than at the start of this function. The construction now happens in ConstructMessage(). Also added in functionality to call failure function on message when not acknowledged and to cancel message after a set number of retries. Implemented the functionality for the MsgDescr::noResend flag. Added message approvals to client-side sending.

Parameters:

	msg	The message to transmit.
	inSys	True if the message has been added to the heap and tree tracking messages in the system. This value will be false when called from AddMessage() because the resend time will be set while in this function.

Returns:: True on success, false if the message was not sent because of error or no recipients.

Author:: Jeff Jackowski

Definition at line 458 of file message.c.

References AATreeRemove, SocketAddr_t::addr, MsgDescr_t::approveFunc, MsgDescr_t::bcast, MsgDescr_t::buffer, BufferFree(), MsgDescr_t::buffLifeUnmanaged, clients, NetBuffer_t::data, MsgDescr_t::destMap, DESTMAPLEN, DESTMAPTYPE, MsgDescr_t::failFunc, FALSE, ClientData_t::flags, MsgDescr_t::inflight, inflightId, MsgDescr_t::interval, SocketAddr_t::ipv4, SocketAddr_t::length, NetBuffer_t::length, localPlayer, MAX_PLAYERS, MessageFree(), MSG_TYPE_CONN_DISCONN, MsgDescr_t::msgId, NETSTATE_CLIDISCONN, NETSTATE_CLIENT, NETSTATE_RCVCFG, networkState, MsgDescr_t::nextSend, MsgDescr_t::noResend, outgoingAddr, sock, MsgDescr_t::triesLeft, and TRUE.

Referenced by AddMessage(), and ServiceMessages().

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Bool SendDisconnectMessage ( Uint8 id )

Sends a disconnect message (see MSG_TYPE_CONN_DISCONN and the data format) indicating the specified client is leaving the game.

The message is sent using the messaging system.

Parameters:

The client ID of the host leaving the game. For servers, the value should be zero.

Returns:: True if the message was transmitted.

Author:: Jeff Jackowski

Definition at line 1367 of file message.c.

References MsgDescr_t::ackFunc, AddMessage(), MsgDescr_t::approveFunc, MsgDescr_t::bcast, MsgDescr_t::buffer, BufferNew(), NetBuffer_t::data, MsgDescr_t::destMap, MsgDescr_t::failFunc, FALSE, INIT_TRIES, NetBuffer_t::length, MessageFree(), MessageNew(), MSG_TYPE_CONN_DISCONN, MsgFailDropConnection(), NETSTATE_SERVER, networkState, SetDestToAll, MsgDescr_t::triesLeft, and TRUE.

Referenced by HandleConnDisconn(), MsgFailDisconnect(), MsgFailDropConnection(), NetDisconnect(), and NetUninit().

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void ServiceMessages ( )

Services the outgoing messages that are already in the system.

This includes removing messages that have been acknowledged by all recipients, and resending messages that haven't.

Author:: Jeff Jackowski

Definition at line 692 of file message.c.

References AATreeFind(), AANode_t::data, inflightId, inflightTime, AANode_t::key, MsgDescr_t::msgId, NETSTATE_CONNECTING, NETSTATE_SERVER, networkState, MsgDescr_t::nextSend, Send(), TRUE, Vector_t::VectorFirst, Vector_t::VectorHeapPop(), and Vector_t::VectorHeapPush().

Referenced by Disconnect(), and ProcessNetworkMessages().

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Bool ValidateClient	(	SocketAddr *	origin,
		Uint8	clientId
	)

Determines if incomming client data came from a valid source.

This function relies on data returned from socket functions of the operating system, and as such is suseptible to things like spoofing.

Parameters:

	origin	The originating address of the data.
	clientId	The reported identity of the client.

Returns:: True if it appears the data came from the indicated client, false if the data seems to have come from another source.

Author:: Jeff Jackowski

Definition at line 743 of file message.c.

References ClientData_t::addr, clients, SocketAddr_t::EqualAddresses, FALSE, localPlayer, MAX_PLAYERS, and TRUE.

Referenced by HandleAck(), HandleConnDisconn(), HandlePlayerSpawn(), HandlePlayerUpdate(), and ServerTimeSyncThread().

Bool ValidateServer ( SocketAddr * origin )

Determines if the inomming server data came from the server that is running the game, and if this process is a client.

Parameters:

origin

The originating address of the data.

Returns:: True if it appears the data came from the server and should not be ignored.

Author:: Jeff Jackowski

Definition at line 761 of file message.c.

References SocketAddr_t::EqualAddresses, FALSE, NETSTATE_CLIDISCONN, NETSTATE_CLIENT, NETSTATE_RCVCFG, networkState, outgoingAddr, and TRUE.

Referenced by HandleAck(), HandleArea(), HandleConnDeny(), HandleConnDisconn(), HandleGameOption(), HandleObstacle(), HandlePlayerUpdate(), and HandleScoreUpdate().

Generated on Mon May 28 04:41:42 2007 for Retro Tank Super Attack by

1.5.2

Messaging System [Networking]

Files

Data Structures

Defines

Typedefs

Enumerations

Functions

Detailed Description

Define Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation

Messaging System
[Networking]