forked from iPodLinux-Community/igpSP
-
Notifications
You must be signed in to change notification settings - Fork 0
/
cheats.c
388 lines (320 loc) · 8.81 KB
/
cheats.c
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
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
/* gameplaySP
*
* Copyright (C) 2006 Exophase <[email protected]>
*
* 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 (at your option) 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "common.h"
cheat_type cheats[MAX_CHEATS];
u32 num_cheats;
void decrypt_gsa_code(u32 *address_ptr, u32 *value_ptr, cheat_variant_enum
cheat_variant)
{
u32 i, i2, code_position;
u32 address = *address_ptr;
u32 value = *value_ptr;
u32 r = 0xc6ef3720;
u32 seeds_v1[4] =
{
0x09f4fbbd, 0x9681884a, 0x352027e9, 0xf3dee5a7
};
u32 seeds_v3[4] =
{
0x7aa9648f, 0x7fae6994, 0xc0efaad5, 0x42712c57
};
u32 *seeds;
if(cheat_variant == CHEAT_TYPE_GAMESHARK_V1)
seeds = seeds_v1;
else
seeds = seeds_v3;
for(i = 0; i < 32; i++)
{
value -= ((address << 4) + seeds[2]) ^ (address + r) ^
((address >> 5) + seeds[3]);
address -= ((value << 4) + seeds[0]) ^ (value + r) ^
((value >> 5) + seeds[1]);
r -= 0x9e3779b9;
}
*address_ptr = address;
*value_ptr = value;
}
void add_cheats(u8 *cheats_filename)
{
FILE *cheats_file;
u8 current_line[256];
u8 *name_ptr;
u32 *cheat_code_ptr;
u32 address, value;
u32 num_cheat_lines;
u32 cheat_name_length;
cheat_variant_enum current_cheat_variant;
num_cheats = 0;
cheats_file = fopen(cheats_filename, "rb");
if(cheats_file)
{
while(fgets(current_line, 256, cheats_file))
{
// Get the header line first
name_ptr = strchr(current_line, ' ');
if(name_ptr)
{
*name_ptr = 0;
name_ptr++;
}
if(!strcasecmp(current_line, "gameshark_v1") ||
!strcasecmp(current_line, "gameshark_v2") ||
!strcasecmp(current_line, "PAR_v1") ||
!strcasecmp(current_line, "PAR_v2"))
{
current_cheat_variant = CHEAT_TYPE_GAMESHARK_V1;
}
else
if(!strcasecmp(current_line, "gameshark_v3") ||
!strcasecmp(current_line, "PAR_v3"))
{
current_cheat_variant = CHEAT_TYPE_GAMESHARK_V3;
}
else
{
current_cheat_variant = CHEAT_TYPE_INVALID;
}
if(current_cheat_variant != CHEAT_TYPE_INVALID)
{
strncpy(cheats[num_cheats].cheat_name, name_ptr, CHEAT_NAME_LENGTH - 1);
cheats[num_cheats].cheat_name[CHEAT_NAME_LENGTH - 1] = 0;
cheat_name_length = strlen(cheats[num_cheats].cheat_name);
if(cheat_name_length &&
(cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\n') ||
(cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\r'))
{
cheats[num_cheats].cheat_name[cheat_name_length - 1] = 0;
cheat_name_length--;
}
if(cheat_name_length &&
cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\r')
{
cheats[num_cheats].cheat_name[cheat_name_length - 1] = 0;
}
cheats[num_cheats].cheat_variant = current_cheat_variant;
cheat_code_ptr = cheats[num_cheats].cheat_codes;
num_cheat_lines = 0;
while(fgets(current_line, 256, cheats_file))
{
if(strlen(current_line) < 3)
break;
sscanf(current_line, "%08x %08x", &address, &value);
decrypt_gsa_code(&address, &value, current_cheat_variant);
cheat_code_ptr[0] = address;
cheat_code_ptr[1] = value;
cheat_code_ptr += 2;
num_cheat_lines++;
}
cheats[num_cheats].num_cheat_lines = num_cheat_lines;
num_cheats++;
}
}
fclose(cheats_file);
}
}
void process_cheat_gs1(cheat_type *cheat)
{
u32 cheat_opcode;
u32 *code_ptr = cheat->cheat_codes;
u32 address, value;
u32 i;
for(i = 0; i < cheat->num_cheat_lines; i++)
{
address = code_ptr[0];
value = code_ptr[1];
code_ptr += 2;
cheat_opcode = address >> 28;
address &= 0xFFFFFFF;
switch(cheat_opcode)
{
case 0x0:
write_memory8(address, value);
break;
case 0x1:
write_memory16(address, value);
break;
case 0x2:
write_memory32(address, value);
break;
case 0x3:
{
u32 num_addresses = address & 0xFFFF;
u32 address1, address2;
u32 i2;
for(i2 = 0; i2 < num_addresses; i2++)
{
address1 = code_ptr[0];
address2 = code_ptr[1];
code_ptr += 2;
i++;
write_memory32(address1, value);
if(address2 != 0)
write_memory32(address2, value);
}
break;
}
// ROM patch not supported yet
case 0x6:
break;
// GS button down not supported yet
case 0x8:
break;
// Reencryption (DEADFACE) not supported yet
case 0xD:
if(read_memory16(address) != (value & 0xFFFF))
{
code_ptr += 2;
i++;
}
break;
case 0xE:
if(read_memory16(value & 0xFFFFFFF) != (address & 0xFFFF))
{
u32 skip = ((address >> 16) & 0x03);
code_ptr += skip * 2;
i += skip;
}
break;
// Hook routine not supported yet (not important??)
case 0x0F:
break;
}
}
}
// These are especially incomplete.
void process_cheat_gs3(cheat_type *cheat)
{
u32 cheat_opcode;
u32 *code_ptr = cheat->cheat_codes;
u32 address, value;
u32 i;
for(i = 0; i < cheat->num_cheat_lines; i++)
{
address = code_ptr[0];
value = code_ptr[1];
code_ptr += 2;
cheat_opcode = address >> 28;
address &= 0xFFFFFFF;
switch(cheat_opcode)
{
case 0x0:
cheat_opcode = address >> 24;
address = (address & 0xFFFFF) + ((address << 4) & 0xF000000);
switch(cheat_opcode)
{
case 0x0:
{
u32 iterations = value >> 24;
u32 i2;
value &= 0xFF;
for(i2 = 0; i2 <= iterations; i2++, address++)
{
write_memory8(address, value);
}
break;
}
case 0x2:
{
u32 iterations = value >> 16;
u32 i2;
value &= 0xFFFF;
for(i2 = 0; i2 <= iterations; i2++, address += 2)
{
write_memory16(address, value);
}
break;
}
case 0x4:
write_memory32(address, value);
break;
}
break;
case 0x4:
cheat_opcode = address >> 24;
address = (address & 0xFFFFF) + ((address << 4) & 0xF000000);
switch(cheat_opcode)
{
case 0x0:
address = read_memory32(address) + (value >> 24);
write_memory8(address, value & 0xFF);
break;
case 0x2:
address = read_memory32(address) + ((value >> 16) * 2);
write_memory16(address, value & 0xFFFF);
break;
case 0x4:
address = read_memory32(address);
write_memory32(address, value);
break;
}
break;
case 0x8:
cheat_opcode = address >> 24;
address = (address & 0xFFFFF) + ((address << 4) & 0xF000000);
switch(cheat_opcode)
{
case 0x0:
value = (value & 0xFF) + read_memory8(address);
write_memory8(address, value);
break;
case 0x2:
value = (value & 0xFFFF) + read_memory16(address);
write_memory16(address, value);
break;
case 0x4:
value = value + read_memory32(address);
write_memory32(address, value);
break;
}
break;
case 0xC:
cheat_opcode = address >> 24;
address = (address & 0xFFFFFF) + 0x4000000;
switch(cheat_opcode)
{
case 0x6:
write_memory16(address, value);
break;
case 0x7:
write_memory32(address, value);
break;
}
break;
}
}
}
void process_cheats()
{
u32 i;
for(i = 0; i < num_cheats; i++)
{
if(cheats[i].cheat_active)
{
switch(cheats[i].cheat_variant)
{
case CHEAT_TYPE_GAMESHARK_V1:
process_cheat_gs1(cheats + i);
break;
case CHEAT_TYPE_GAMESHARK_V3:
process_cheat_gs3(cheats + i);
break;
}
}
}
}