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
|
/*
* The Mana Client
* Copyright (C) 2004-2009 The Mana World Development Team
* Copyright (C) 2009-2012 The Mana Developers
*
* This file is part of The Mana Client.
*
* 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
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "net/tmwa/messagein.h"
#include <SDL.h>
#include <SDL_endian.h>
#define MAKEWORD(low,high) \
((unsigned short)(((unsigned char)(low)) | \
((unsigned short)((unsigned char)(high))) << 8))
namespace TmwAthena {
MessageIn::MessageIn(const char *data, unsigned int length):
mData(data),
mLength(length),
mPos(0)
{
// Read the message ID
mId = readInt16();
}
uint8_t MessageIn::readInt8()
{
uint8_t value = 0;
if (mPos < mLength)
{
value = mData[mPos];
}
mPos++;
return value;
}
uint16_t MessageIn::readInt16()
{
uint16_t value = 0;
if (mPos + 2 <= mLength)
{
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
uint16_t swap;
memcpy(&swap, mData + mPos, sizeof(uint16_t));
value = SDL_Swap16(swap);
#else
memcpy(&value, mData + mPos, sizeof(uint16_t));
#endif
}
mPos += 2;
return value;
}
uint32_t MessageIn::readInt32()
{
uint32_t value = 0;
if (mPos + 4 <= mLength)
{
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
uint32_t swap;
memcpy(&swap, mData + mPos, sizeof(uint32_t));
value = SDL_Swap32(swap);
#else
memcpy(&value, mData + mPos, sizeof(uint32_t));
#endif
}
mPos += 4;
return value;
}
void MessageIn::readCoordinates(uint16_t &x, uint16_t &y, uint8_t &direction)
{
if (mPos + 3 <= mLength)
{
const char *data = mData + mPos;
uint16_t temp;
temp = MAKEWORD(data[1] & 0x00c0, data[0] & 0x00ff);
x = temp >> 6;
temp = MAKEWORD(data[2] & 0x00f0, data[1] & 0x003f);
y = temp >> 4;
direction = data[2] & 0x000f;
// Translate from tmwAthena format
switch (direction)
{
case 0:
direction = 1;
break;
case 1:
direction = 3;
break;
case 2:
direction = 2;
break;
case 3:
direction = 6;
break;
case 4:
direction = 4;
break;
case 5:
direction = 12;
break;
case 6:
direction = 8;
break;
case 7:
direction = 9;
break;
case 8:
direction = 8;
break;
default:
// OOPSIE! Impossible or unknown
direction = 0;
}
}
mPos += 3;
}
void MessageIn::readCoordinatePair(uint16_t &srcX, uint16_t &srcY,
uint16_t &dstX, uint16_t &dstY)
{
if (mPos + 5 <= mLength)
{
const char *data = mData + mPos;
uint16_t temp;
temp = MAKEWORD(data[3], data[2] & 0x000f);
dstX = temp >> 2;
dstY = MAKEWORD(data[4], data[3] & 0x0003);
temp = MAKEWORD(data[1], data[0]);
srcX = temp >> 6;
temp = MAKEWORD(data[2], data[1] & 0x003f);
srcY = temp >> 4;
}
mPos += 5;
}
void MessageIn::skip(unsigned int length)
{
mPos += length;
}
std::string MessageIn::readString(int length)
{
// Get string length
if (length < 0)
length = readInt16();
// Make sure the string isn't erroneous
if (length < 0 || mPos + length > mLength)
{
mPos = mLength + 1;
return "";
}
// Read the string
char const *stringBeg = mData + mPos;
char const *stringEnd = (char const *)memchr(stringBeg, '\0', length);
std::string readString(stringBeg,
stringEnd ? stringEnd - stringBeg : length);
mPos += length;
return readString;
}
} // namespace TmwAthena
|
