1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
/* Starshatter OpenSource Distribution
Copyright (c) 1997-2004, Destroyer Studios LLC.
All Rights Reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name "Destroyer Studios" nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
SUBSYSTEM: NetEx.lib
FILE: NetGram.h
AUTHOR: John DiCamillo
OVERVIEW
========
Datagram (UDP) packet that implements the basic
packet-oriented network protocol.
*/
#ifndef NetGram_h
#define NetGram_h
#include <windows.h>
#include "NetAddr.h"
#include "Text.h"
// +-------------------------------------------------------------------+
const int NET_GRAM_ACK = 0x80000000;
const int NET_GRAM_RELIABLE = 0x40000000;
const int NET_GRAM_SEQ_MASK = 0x3fffffff;
const int NET_GRAM_HEADER_SIZE = 4;
const int NET_GRAM_MAX_SIZE = 1024;
// +-------------------------------------------------------------------+
class NetGram
{
public:
static const char* TYPENAME() { return "NetGram"; }
// for receiving packets from remote hosts:
NetGram(const NetAddr& src, Text msg);
// for composing packets to send to remote hosts:
NetGram(const NetAddr& dst, Text user_data, int retries);
int operator == (const NetGram& g) const { return packet_id == g.packet_id &&
addr == g.addr; }
int operator < (const NetGram& g) const { return Sequence() < g.Sequence(); }
DWORD PacketID() const { return packet_id; }
DWORD Sequence() const { return packet_id & NET_GRAM_SEQ_MASK; }
DWORD SendTime() const { return send_time; }
BYTE* Data() const { return (BYTE*) body.data(); }
BYTE* UserData() const { return (BYTE*) body.data() + NET_GRAM_HEADER_SIZE; }
int Size() const { return body.length(); }
const Text& Body() const { return body; }
const NetAddr& Address() const { return addr; }
bool IsAck() const { return packet_id & NET_GRAM_ACK ? true : false; }
bool IsReliable() const { return packet_id & NET_GRAM_RELIABLE ? true : false; }
int Retries() const { return retries; }
void Retry();
NetGram Ack();
void ClearAck() { packet_id &= ~NET_GRAM_ACK; }
protected:
NetGram();
NetAddr addr; // network address of remote host
int retries; // number of retries remaining (reliable packets only)
DWORD send_time; // time in msec of most recent send attempt
DWORD packet_id; // copy of packet id from header in body
Text body; // header plus user data
};
#endif // NetGram_h
|
