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
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
|
/*
Copyright 2016-2019 Arisotura
This file is part of melonDS.
melonDS 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 3 of the License, or (at your option)
any later version.
melonDS 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 melonDS. If not, see http://www.gnu.org/licenses/.
*/
#include <stdio.h>
#include "Savestate.h"
#include "melon_fopen.h"
/*
Savestate format
header:
00 - magic MELN
04 - version major
06 - version minor
08 - length
0C - game serial
10 - ARM9 binary checksum
14 - ARM7 binary checksum
18 - reserved
1C - reserved
section header:
00 - section magic
04 - section length
08 - reserved
0C - reserved
Implementation details
version difference:
* different major means savestate file is incompatible
* different minor means adjustments may have to be made
*/
Savestate::Savestate(char* filename, bool save)
{
char* magic = "MELN";
Error = false;
if (save)
{
Saving = true;
file = melon_fopen(filename, "wb");
if (!file)
{
printf("savestate: file %s doesn't exist\n", filename);
Error = true;
return;
}
VersionMajor = SAVESTATE_MAJOR;
VersionMinor = SAVESTATE_MINOR;
fwrite(magic, 4, 1, file);
fwrite(&VersionMajor, 2, 1, file);
fwrite(&VersionMinor, 2, 1, file);
fseek(file, 8, SEEK_CUR); // length to be fixed later
}
else
{
Saving = false;
file = melon_fopen(filename, "rb");
if (!file)
{
printf("savestate: file %s doesn't exist\n", filename);
Error = true;
return;
}
u32 len;
fseek(file, 0, SEEK_END);
len = (u32)ftell(file);
fseek(file, 0, SEEK_SET);
u32 buf = 0;
fread(&buf, 4, 1, file);
if (buf != ((u32*)magic)[0])
{
printf("savestate: invalid magic %08X\n", buf);
Error = true;
return;
}
VersionMajor = 0;
VersionMinor = 0;
fread(&VersionMajor, 2, 1, file);
if (VersionMajor != SAVESTATE_MAJOR)
{
printf("savestate: bad version major %d, expecting %d\n", VersionMajor, SAVESTATE_MAJOR);
Error = true;
return;
}
fread(&VersionMinor, 2, 1, file);
// TODO: handle it???
buf = 0;
fread(&buf, 4, 1, file);
if (buf != len)
{
printf("savestate: bad length %d\n", buf);
Error = true;
return;
}
fseek(file, 4, SEEK_CUR);
}
CurSection = -1;
}
Savestate::~Savestate()
{
if (Error) return;
if (Saving)
{
if (CurSection != -1)
{
u32 pos = (u32)ftell(file);
fseek(file, CurSection+4, SEEK_SET);
u32 len = pos - CurSection;
fwrite(&len, 4, 1, file);
fseek(file, pos, SEEK_SET);
}
fseek(file, 0, SEEK_END);
u32 len = (u32)ftell(file);
fseek(file, 8, SEEK_SET);
fwrite(&len, 4, 1, file);
}
if (file) fclose(file);
}
void Savestate::Section(char* magic)
{
if (Error) return;
if (Saving)
{
if (CurSection != -1)
{
u32 pos = (u32)ftell(file);
fseek(file, CurSection+4, SEEK_SET);
u32 len = pos - CurSection;
fwrite(&len, 4, 1, file);
fseek(file, pos, SEEK_SET);
}
CurSection = (u32)ftell(file);
fwrite(magic, 4, 1, file);
fseek(file, 12, SEEK_CUR);
}
else
{
fseek(file, 0x10, SEEK_SET);
for (;;)
{
u32 buf = 0;
fread(&buf, 4, 1, file);
if (buf != ((u32*)magic)[0])
{
if (buf == 0)
{
printf("savestate: section %s not found. blarg\n", magic);
return;
}
buf = 0;
fread(&buf, 4, 1, file);
fseek(file, buf-8, SEEK_CUR);
continue;
}
fseek(file, 12, SEEK_CUR);
break;
}
}
}
void Savestate::Var8(u8* var)
{
if (Error) return;
if (Saving)
{
fwrite(var, 1, 1, file);
}
else
{
fread(var, 1, 1, file);
}
}
void Savestate::Var16(u16* var)
{
if (Error) return;
if (Saving)
{
fwrite(var, 2, 1, file);
}
else
{
fread(var, 2, 1, file);
}
}
void Savestate::Var32(u32* var)
{
if (Error) return;
if (Saving)
{
fwrite(var, 4, 1, file);
}
else
{
fread(var, 4, 1, file);
}
}
void Savestate::Var64(u64* var)
{
if (Error) return;
if (Saving)
{
fwrite(var, 8, 1, file);
}
else
{
fread(var, 8, 1, file);
}
}
void Savestate::VarArray(void* data, u32 len)
{
if (Error) return;
if (Saving)
{
fwrite(data, len, 1, file);
}
else
{
fread(data, len, 1, file);
}
}
|