Serious-Engine/Sources/Engine/Network/CPacket.h
2016-03-11 15:57:17 +02:00

182 lines
6.6 KiB
C++

/* Copyright (c) 2002-2012 Croteam Ltd. All rights reserved. */
#ifndef SE_INCL_PACKET_H
#define SE_INCL_PACKET_H
#ifdef PRAGMA_ONCE
#pragma once
#endif
#include <Engine/Base/Lists.h>
#include <Engine/Base/Timer.h>
// The total size of the UDP packet should be below 1450 bytes, to reduce the
// packet drop rate caused by routers dropping large UDP packets. UDP_BLOCK_SIZE is the
// maximum length of real data, not counting the packet header (ulPacketSequence, bReliable,uwID)
#define MAX_UDP_BLOCK_SIZE 1400
#define MAX_HEADER_SIZE (sizeof(UBYTE) + sizeof(ULONG) + sizeof(UWORD) + sizeof(ULONG)) // pa_bReliable + pa_ulPacketSequence + pa_uwID + pa_ulTransferSize
#define MAX_PACKET_SIZE (MAX_UDP_BLOCK_SIZE + MAX_HEADER_SIZE)
// flags for different kinds of packets used by the netcode - note that the acknowledge packets are unreliable
#define UDP_PACKET_UNRELIABLE 0
#define UDP_PACKET_RELIABLE 1
#define UDP_PACKET_RELIABLE_HEAD 2
#define UDP_PACKET_RELIABLE_TAIL 4
#define UDP_PACKET_ACKNOWLEDGE 8
#define UDP_PACKET_CONNECT_REQUEST 16
#define UDP_PACKET_CONNECT_RESPONSE 32
// constants for CPacket::CanRetry() function - they describe the retry state of the packet
#define RS_NOW 0 // the packet should be resent immediately
#define RS_NOTNOW 1 // the packet should be resent at a later time
#define RS_NOTATALL 2 // the packet has reached the maximum number of retries - give up
class CAddress {
public:
ULONG adr_ulAddress; // host address
UWORD adr_uwPort; // host port
UWORD adr_uwID; // host id
void MakeBroadcast(void);
void Clear(void) {
adr_ulAddress = 0;
adr_uwPort = 0;
adr_uwID = 0;
}
};
/*
* A class that contains a single UDP packet.
*/
class CPacket {
public:
ULONG pa_ulSequence; // Sequence number of this packet
UBYTE pa_ubReliable; // Is packet reliable or not
SLONG pa_slSize; // Number of data bytes in packet (without header)
SLONG pa_slTransferSize; // Number of data bytes in a data transfer unit this packet belongs to
UBYTE pa_ubRetryNumber; // How many retries so far for this packet
CTimerValue pa_tvSendWhen; // When to try sending this packet (includes latency bandwidth limitations
// as well as retry intervals)
UBYTE pa_pubPacketData[MAX_PACKET_SIZE]; // Packet header + actual data contained in the packet
CListNode pa_lnListNode; // used to create a linked list of packets - buffer
CAddress pa_adrAddress; // packet address, port and client ID
// Constructors/destructors
CPacket() { Clear(); } // Default Constructor
CPacket(CPacket &paOriginal); // Copy constructor
~CPacket() { Clear(); }
// Reset all packet data and free allocated memory
void Clear();
// Write data to the packet and add header data
BOOL WriteToPacket(void* pv,SLONG slSize,UBYTE ubReliable,ULONG ulSequence,UWORD uwClientID,SLONG slTransferSize);
// Write raw data to the packet and extract header data from the data
BOOL WriteToPacketRaw(void* pv,SLONG slSize);
// Read data from the packet (no header data)
BOOL ReadFromPacket(void* pv,SLONG &slExpectedSize);
// Is packet reliable
BOOL IsReliable();
// Is packet a head of a reliable stream?
BOOL IsReliableHead();
// Is packet a tail of a reliable stream?
BOOL IsReliableTail();
// Is the packet from a broadcast address (pa_uwID not assigned)
BOOL IsBroadcast();
// Get the sequence number of the packet (must be reliable)
ULONG GetSequence();
// What is the current retry status?
UBYTE CanRetry();
// Drop the packet from the list
void Drop();
// get the size of data transfer unit this packet belongs to
SLONG CPacket::GetTransferSize();
// Copy operator
void operator=(const CPacket &paOriginal);
};
// data used to limit bandwidth/lantency and calculate statistics in packet-buffers
class CPacketBufferStats {
public:
FLOAT pbs_fLatencyLimit; // minimum latency in seconds
FLOAT pbs_fLatencyVariation;// additional latency variation
FLOAT pbs_fBandwidthLimit; // maximum bandwidth in bps (bits per second)
CTimerValue pbs_tvTimeNextPacketStart; // next point in time free for data receiving
void Clear(void);
// get time when the packet will be allowed to leave the buffer
CTimerValue GetPacketSendTime(SLONG slSize);
};
class CPacketBuffer {
public:
ULONG pb_ulTotalSize; // Total size of data in packets stored in this buffer (no headers)
ULONG pb_ulLastSequenceOut; // Sequence number of the last packet taken out of the buffer
CListHead pb_lhPacketStorage;
ULONG pb_ulNumOfPackets; // Total number of packets currently in storage
ULONG pb_ulNumOfReliablePackets; // Number of reliable packets in storage (0 if no reliable stream in progress)
CPacketBufferStats *pb_ppbsStats; // for bandwidth/latency emulation stats and limits
CPacketBufferStats pb_pbsLimits; // maximum output BPS for the buffer, to prevent client flooding
CPacketBuffer() { Clear(); };
~CPacketBuffer() { Clear(); };
// Empty the packet buffer
void Clear();
// Is the packet buffer empty?
BOOL IsEmpty();
// Calculate when the packet can be output from the buffer
CTimerValue GetPacketSendTime(SLONG slSize);
// Adds a packet to the end of the packet buffer
BOOL AppendPacket(CPacket &paPacket,BOOL bDelay);
// Inserts the packet in the buffer, according to it's sequence number
BOOL InsertPacket(CPacket &paPacket,BOOL bDelay);
// Bumps up the retry count and time, and appends the packet to the buffer
BOOL Retry(CPacket &paPacket);
// Reads the data from the first packet in the bufffer, but does not remove it
CPacket* PeekFirstPacket();
// Reads the first packet in the bufffer
CPacket* GetFirstPacket();
// Reads the data from the packet with the requested sequence, but does not remove it
CPacket* PeekPacket(ULONG ulSequence);
// Reads the packet with the requested sequence
CPacket* GetPacket(ULONG ulSequence);
// Reads the first connection request packet from the buffer
CPacket* GetConnectRequestPacket();
// Removes the first packet from the buffer
BOOL RemoveFirstPacket(BOOL bDelete);
// Removes the packet with the requested sequence from the buffer
BOOL RemovePacket(ULONG ulSequence,BOOL bDelete);
// Remove connect response packets from the buffer
BOOL RemoveConnectResponsePackets();
// Gets the sequence number of the first packet in the buffer
ULONG GetFirstSequence();
// Gets the sequence number of the last packet in the buffer
ULONG GetLastSequence();
// Is the packet with the given sequence in the buffer?
BOOL IsSequenceInBuffer(ULONG ulSequence);
// Check if the buffer contains a complete sequence of reliable packets at the start of the buffer
BOOL CheckSequence(SLONG &slSize);
};
#endif /* include-once check. */