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
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/*
* This file is part of Magellan <http://www.kAlliance.org/Magellan>
*
* Copyright (c) 1998-2000 Teodor Mihai <teddy@ireland.com>
* Copyright (c) 1998-2000 Laur Ivan <laur.ivan@ul.ie>
* Copyright (c) 1999-2000 Virgil Palanciuc <vv@ulise.cs.pub.ro>
*
* Requires the Qt widget libraries, available at no cost at
* http://www.troll.no/
*
* Also requires the KDE libraries, available at no cost at
* http://www.kde.org/
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include <commframe.h>
#include <qdatastream.h>
#include <iostream.h>
CommFrame::CommFrame()
{
reset();
}
CommFrame::CommFrame(QByteArray data)
{
setData(data);
}
bool CommFrame::setData(QByteArray data)
{
// reset frame
reset();
// check if we have at least the whole header
if(data.size()<14)
{
printf("Invalid frame (length<14), bailing out\n");
return false;
}
// get a data stream
QDataStream s(data, IO_ReadOnly);
// check the Magellan signature byte
unsigned char t,u;
s>>t;
if(t!='M')
{
printf("Invalid frame (wrong signature byte), bailing out\n");
return false;
}
// get the software version
s>>t;
u=t;
t=t>>4;
u=u<<4;
u=u>>4;
majorRevNo=t;
minorRevNo=u;
// check software version (only 1.1 is accepted right now)
if(majorRevNo!=1||minorRevNo!=1)
{
printf("Invalid frame (wrong software revision), bailing out\n");
return false;
}
// get the frame characteristics
s>>t;
s>>u; // reserved for future use
if(t&0x80) requestFrame=true;
else replyFrame=true;
if(t&0x40) clientFrame=true;
else serverFrame=true;
// test the controlled reply behavior
if(!t&0x20)
{
if(t&0x10) requestsReply=true;
else deniesReply=true;
}
if(t&0x08) hasStatus=true;
if(t&0x04) hasData=true;
// test the frame characteristics
if(requestFrame==replyFrame
|| requestsReply&&deniesReply
|| serverFrame==clientFrame)
{
printf("Invalid frame (wrong combination of flags), bailing out\n");
return false;
}
// get the transaction number
s>>transactionTag;
// get the sequence number
s>>sequenceTag;
// get the command code
s>>commandCode;
// get the status, if available
if(hasStatus)
{
s>>statusCode;
s>>statusString;
}
if(hasData)
s>>extraData;
// we should have reached the end of the stream
if(!s.atEnd())
{
printf("Invalid frame (could not reach the end of data stream), bailing out\n");
return false;
}
validity=true;
printf("Frame successfully parsed.\n");
return true;
}
bool CommFrame::isValid()
{
return validity;
}
void CommFrame::reset()
{
frameLength=0;
majorRevNo=0;
minorRevNo=0;
requestFrame=false;
replyFrame=false;
serverFrame=false;
clientFrame=false;
requestsReply=false;
deniesReply=false;
hasStatus=false;
hasData=false;
transactionTag=0;
sequenceTag=0;
commandCode=0;
statusCode=0;
statusString=QString::null;
extraData.truncate(0);
validity=false;
}
CommFrame::operator QByteArray()
{
QByteArray a;
QDataStream s(a, IO_WriteOnly);
// write the Magellan signature byte
s<<(unsigned char)'M';
// write the software version number
s<<(unsigned char)0x11;
// compute the type byte
unsigned char t=0;
if(requestFrame) t=t|0x80;
if(clientFrame) t=t|0x40;
if(requestsReply||deniesReply)
{
t=t|0x20;
if(requestsReply) t=t|0x10;
}
if(hasStatus) t=t|0x08;
if(hasData) t=t|0x04;
// write the frame type (2 bytes, 10 bits reserved for future use)
s<<(unsigned char)t;
s<<(unsigned char)0;
// write the transaction number
s<<(unsigned int)transactionTag;
// write the sequence number
s<<(unsigned int)sequenceTag;
// write the command code
s<<(unsigned int)commandCode;
// write the frame data
if(hasStatus)
{
s<<(unsigned int)statusCode;
s<<statusString;
}
if(hasData)
s<<extraData;
return a;
}
|
