aboutsummaryrefslogtreecommitdiff
path: root/libretro.c
blob: d5535902c46b1dd8da8c9cab73b745f6666ae004 (plain)
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
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
#include <stdio.h>

#include "snes9x.h"
#include "soundux.h"
#include "memmap.h"
#include "apu.h"
#include "cheats.h"
#include "display.h"
#include "gfx.h"
#include "cpuexec.h"
#include "spc7110.h"
#include "srtc.h"

#include <libretro.h>

static retro_log_printf_t log_cb = NULL;
static retro_video_refresh_t video_cb = NULL;
static retro_input_poll_t poll_cb = NULL;
static retro_input_state_t input_cb = NULL;
static retro_audio_sample_batch_t audio_batch_cb = NULL;
static retro_environment_t environ_cb = NULL;


struct retro_perf_callback perf_cb;

void retro_set_environment(retro_environment_t cb)
{
   struct retro_log_callback log;

   environ_cb = cb;

   if (environ_cb(RETRO_ENVIRONMENT_GET_LOG_INTERFACE, &log))
      log_cb = log.log;
   else
      log_cb = NULL;

   environ_cb(RETRO_ENVIRONMENT_GET_PERF_INTERFACE, &perf_cb);

}


void retro_set_video_refresh(retro_video_refresh_t cb)
{
   video_cb = cb;
}

void retro_set_audio_sample(retro_audio_sample_t cb)
{}

void retro_set_audio_sample_batch(retro_audio_sample_batch_t cb)
{
   audio_batch_cb = cb;
}

void retro_set_input_poll(retro_input_poll_t cb)
{
   poll_cb = cb;
}

void retro_set_input_state(retro_input_state_t cb)
{
   input_cb = cb;
}

void retro_set_controller_port_device(unsigned port, unsigned device) {}

unsigned retro_api_version()
{
   return RETRO_API_VERSION;
}

void S9xMessage(int type, int number, const char* message)
{
#if 1
#define MAX_MESSAGE_LEN (36 * 3)

   static char buffer [MAX_MESSAGE_LEN + 1];

   printf("%s\n", message);
   strncpy(buffer, message, MAX_MESSAGE_LEN);
   buffer [MAX_MESSAGE_LEN] = 0;
   S9xSetInfoString(buffer);
#endif
}

void S9xDeinitDisplay(void)
{
#ifdef DS2_DMA
   if (GFX.Screen_buffer) AlignedFree(GFX.Screen, PtrAdj.GFXScreen);
#else
   if (GFX.Screen_buffer) free(GFX.Screen_buffer);
#endif
   if (GFX.SubScreen_buffer) free(GFX.SubScreen_buffer);
   if (GFX.ZBuffer_buffer) free(GFX.ZBuffer_buffer);
   if (GFX.SubZBuffer_buffer) free(GFX.SubZBuffer_buffer);

   GFX.Screen = NULL;
   GFX.Screen_buffer = NULL;
   GFX.SubScreen = NULL;
   GFX.SubScreen_buffer = NULL;
   GFX.ZBuffer = NULL;
   GFX.ZBuffer_buffer = NULL;
   GFX.SubZBuffer = NULL;
   GFX.SubZBuffer_buffer = NULL;

}

void S9xInitDisplay(void)
{
   int h = IMAGE_HEIGHT;
   const int safety = 32;

   GFX.Pitch = IMAGE_WIDTH * 2;
#ifdef DS2_DMA
   GFX.Screen_buffer = (unsigned char*) AlignedMalloc(GFX.Pitch * h + safety, 32,
                       &PtrAdj.GFXScreen);
#else
   GFX.Screen_buffer = (unsigned char*) malloc(GFX.Pitch * h + safety);
#endif
   GFX.SubScreen_buffer = (unsigned char*) malloc(GFX.Pitch * h + safety);
   GFX.ZBuffer_buffer = (unsigned char*) malloc((GFX.Pitch >> 1) * h + safety);
   GFX.SubZBuffer_buffer = (unsigned char*) malloc((GFX.Pitch >> 1) * h + safety);

   GFX.Screen = GFX.Screen_buffer + safety;
   GFX.SubScreen = GFX.SubScreen_buffer + safety;
   GFX.ZBuffer = GFX.ZBuffer_buffer + safety;
   GFX.SubZBuffer = GFX.SubZBuffer_buffer + safety;


   GFX.Delta = (GFX.SubScreen - GFX.Screen) >> 1;
}

void S9xExit()
{
   //  if(Settings.SPC7110)
   //    (*CleanUp7110)();

   //    S9xDeinitDisplay ();
   //    Memory.SaveSRAM (S9xGetFilename (".srm"));
   //    // S9xSaveCheatFile (S9xGetFilename (".chb")); // cheat binary file
   //   // Do this when loading a cheat file!
   //    Memory.Deinit ();
   //    S9xDeinitAPU ();

   //   exit(0);
}

const char* S9xBasename(const char* f)
{
   const char* p;
   if ((p = strrchr(f, '/')) != NULL || (p = strrchr(f, '\\')) != NULL)
      return (p + 1);

   return (f);
}

bool8 S9xInitUpdate()
{
   //   IPPU.RenderThisFrame = 0;
   //   video_cb(dummy_frame,256,224,512);
   //   return (FALSE);

   return (TRUE);
}

#ifdef PSP
#include <pspkernel.h>
#include <pspgu.h>
void S9xDeinitUpdate(int width, int height)
{
   static unsigned int __attribute__((aligned(16))) d_list[32];
   void* const texture_vram_p = (void*)(0x44200000 - (512 *
                                        512)); // max VRAM address - frame size

   sceKernelDcacheWritebackRange(GFX.Screen, GFX.Pitch * height);

   sceGuStart(GU_DIRECT, d_list);

   sceGuCopyImage(GU_PSM_4444, 0, 0, width, height, GFX.Pitch >> 1, GFX.Screen, 0,
                  0,
                  512, texture_vram_p);

   sceGuTexSync();
   sceGuTexImage(0, 512, 512, 512, texture_vram_p);
   sceGuTexMode(GU_PSM_5551, 0, 0, GU_FALSE);
   sceGuTexFunc(GU_TFX_REPLACE, GU_TCC_RGB);
   sceGuDisable(GU_BLEND);

   sceGuFinish();


   video_cb(texture_vram_p, width, height, GFX.Pitch);
}

#else
void S9xDeinitUpdate(int width, int height)
{
   video_cb(GFX.Screen, width, height, GFX.Pitch);
}

#endif

void _makepath(char* path, const char* drive, const char* dir,
               const char* fname, const char* ext)
{
   if (dir && *dir)
   {
      strcpy(path, dir);
      strcat(path, "/");
   }
   else
      *path = 0;
   strcat(path, fname);
   if (ext && *ext)
   {
      strcat(path, ".");
      strcat(path, ext);
   }
}

void _splitpath(const char* path, char* drive, char* dir, char* fname,
                char* ext)
{
   *drive = 0;

   char* slash = strrchr((char*)path, '/');
   if (!slash)
      slash = strrchr((char*)path, '\\');

   char* dot = strrchr((char*)path, '.');

   if (dot && slash && dot < slash)
      dot = NULL;

   if (!slash)
   {
      strcpy(dir, "");
      strcpy(fname, path);
      if (dot)
      {
         * (fname + (dot - path)) = 0;
         strcpy(ext, dot + 1);
      }
      else
         strcpy(ext, "");
   }
   else
   {
      strcpy(dir, path);
      * (dir + (slash - path)) = 0;
      strcpy(fname, slash + 1);
      if (dot)
      {
         * (fname + (dot - slash) - 1) = 0;
         strcpy(ext, dot + 1);
      }
      else
         strcpy(ext, "");
   }
}


const char* S9xGetSnapshotDirectory()
{
   return ".";
}

const char* S9xGetFilename(const char* ex)
{
   static char filename [PATH_MAX + 1];
   char drive [_MAX_DRIVE + 1];
   char dir [_MAX_DIR + 1];
   char fname [_MAX_FNAME + 1];
   char ext [_MAX_EXT + 1];

   _splitpath(Memory.ROMFilename, drive, dir, fname, ext);
   strcpy(filename, S9xGetSnapshotDirectory());
   strcat(filename, SLASH_STR);
   strcat(filename, fname);
   strcat(filename, ex);

   return (filename);
}


void init_sfc_setting(void)
{
   memset(&Settings, 0, sizeof(Settings));
   Settings.JoystickEnabled = FALSE;
   Settings.SoundPlaybackRate = 44100; // -> ds2sound.h for defs
   Settings.SoundBufferSize = 512;
   Settings.CyclesPercentage = 100;
   Settings.DisableSoundEcho = FALSE;
   //sound settings
   Settings.APUEnabled = Settings.NextAPUEnabled = TRUE;
   // Settings.FixFrequency = 1;

   Settings.H_Max = SNES_CYCLES_PER_SCANLINE;
   Settings.SkipFrames = AUTO_FRAMERATE;
   Settings.ShutdownMaster = TRUE;
   Settings.FrameTimePAL = 20000;
   Settings.FrameTimeNTSC = 16667;
   Settings.DisableMasterVolume = FALSE;
   Settings.Mouse = TRUE;
   Settings.SuperScope = TRUE;
   Settings.MultiPlayer5 = TRUE;
   Settings.ControllerOption = SNES_JOYPAD;

   Settings.Transparency = TRUE;
   Settings.SupportHiRes = TRUE;
   Settings.ThreadSound = FALSE;
   Settings.SoundSync = TRUE;
   Settings.ApplyCheats = TRUE;
   Settings.StretchScreenshots = 1;

   Settings.HBlankStart = (256 * Settings.H_Max) / SNES_HCOUNTER_MAX;
}

void S9xAutoSaveSRAM()
{
   SaveSRAM(S9xGetFilename(".srm"));
}

void retro_init(void)
{
   struct retro_log_callback log;
   enum retro_pixel_format rgb565;

   if (environ_cb(RETRO_ENVIRONMENT_GET_LOG_INTERFACE, &log))
      log_cb = log.log;
   else
      log_cb = NULL;

   rgb565 = RETRO_PIXEL_FORMAT_RGB565;
   if (environ_cb(RETRO_ENVIRONMENT_SET_PIXEL_FORMAT, &rgb565) && log_cb)
      log_cb(RETRO_LOG_INFO,
             "Frontend supports RGB565 - will use that instead of XRGB1555.\n");

   init_sfc_setting();
   Init();
   S9xInitAPU();
   S9xInitDisplay();
   S9xGraphicsInit();
   S9xInitSound(Settings.SoundPlaybackRate,
                TRUE,
                Settings.SoundBufferSize);

}

void retro_deinit(void)
{
   S9xGraphicsDeinit();
   S9xDeinitDisplay();
   S9xDeinitAPU();
   Deinit();
}

uint32 S9xReadJoypad(int port)
{
   static const uint32 snes_lut[] =
   {
      SNES_B_MASK,
      SNES_Y_MASK,
      SNES_SELECT_MASK,
      SNES_START_MASK,
      SNES_UP_MASK,
      SNES_DOWN_MASK,
      SNES_LEFT_MASK,
      SNES_RIGHT_MASK,
      SNES_A_MASK,
      SNES_X_MASK,
      SNES_TL_MASK,
      SNES_TR_MASK
   };

   int i;
   uint32 joypad = 0;

   for (i = RETRO_DEVICE_ID_JOYPAD_B; i <= RETRO_DEVICE_ID_JOYPAD_R; i++)
      if (input_cb(port, RETRO_DEVICE_JOYPAD, 0, i))
         joypad |= snes_lut[i];

   return joypad;
}

//#define FRAMESKIP
void retro_run(void)
{
   int i, port;

   //   IPPU.RenderThisFrame = FALSE;
   //   video_cb(GFX.Screen, 256, 224, 512);

   poll_cb();

   S9xSetPlaybackRate(32040);
   SoundData.echo_enable = FALSE;

   S9xMainLoop();

   static int16_t audio_buf[534 << 1];
   S9xMixSamples((uint8*)audio_buf, 534 << 1);
   audio_batch_cb(audio_buf, 534);


#ifdef FRAMESKIP
   if (IPPU.RenderThisFrame)
      IPPU.RenderThisFrame = false;
   else
   {
      video_cb(NULL, 256, 224, GFX.Pitch);
      IPPU.RenderThisFrame = true;
   }
#endif

   //   if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE, &updated) && updated)
   //      check_variables();

}


void S9xGenerateSound()
{
   //   static s16 audio_buf[855 << 1];
   //   S9xMixSamples ((uint8*)audio_buf, 855 << 1);
   //   audio_batch_cb(audio_buf, 855);



}


void S9xProcessSound(unsigned int samples)
{

}

void S9xLoadSDD1Data()
{

}

bool8 S9xReadMousePosition(int which1, int* x, int* y, uint32* buttons)
{
   return (FALSE);
}

bool8 S9xReadSuperScopePosition(int* x, int* y, uint32* buttons)
{
   return (TRUE);
}

bool JustifierOffscreen()
{
   return (FALSE);
}

void JustifierButtons(uint32* justifiers)
{
}

char* osd_GetPackDir()
{
   static char filename[_MAX_PATH];
   memset(filename, 0, _MAX_PATH);

   if (strlen(S9xGetSnapshotDirectory()) != 0)
      strcpy(filename, S9xGetSnapshotDirectory());
   else
   {
      char dir [_MAX_DIR + 1];
      char drive [_MAX_DRIVE + 1];
      char name [_MAX_FNAME + 1];
      char ext [_MAX_EXT + 1];
      _splitpath(Memory.ROMFilename, drive, dir, name, ext);
      _makepath(filename, drive, dir, NULL, NULL);
   }

   if (!strncmp((char*)&Memory.ROM [0xffc0], "SUPER POWER LEAG 4   ", 21))
   {
      if (getenv("SPL4PACK"))
         return getenv("SPL4PACK");
      else
         strcat(filename, "/SPL4-SP7");
   }
   else if (!strncmp((char*)&Memory.ROM [0xffc0], "MOMOTETSU HAPPY      ", 21))
   {
      if (getenv("MDHPACK"))
         return getenv("MDHPACK");
      else
         strcat(filename, "/SMHT-SP7");
   }
   else if (!strncmp((char*)&Memory.ROM [0xffc0], "HU TENGAI MAKYO ZERO ", 21))
   {
      if (getenv("FEOEZPACK"))
         return getenv("FEOEZPACK");
      else
         strcat(filename, "/FEOEZSP7");
   }
   else if (!strncmp((char*)&Memory.ROM [0xffc0], "JUMP TENGAIMAKYO ZERO", 21))
   {
      if (getenv("SJNSPACK"))
         return getenv("SJNSPACK");
      else
         strcat(filename, "/SJUMPSP7");
   }
   else strcat(filename, "/MISC-SP7");
   return filename;
}

unsigned retro_get_region(void)
{
   return Settings.PAL ? RETRO_REGION_PAL : RETRO_REGION_NTSC;
}
void retro_get_system_info(struct retro_system_info* info)
{
   info->need_fullpath = true;
   info->valid_extensions = "smc|fig|sfc|gd3|gd7|dx2|bsx|swc";
   info->library_version = "v1.4";
   info->library_name = "SNES9x(CATSFC)";
   info->block_extract = false;
}
void retro_get_system_av_info(struct retro_system_av_info* info)
{
   info->geometry.base_width = 256;
   info->geometry.base_height = 224;
   info->geometry.max_width = 512;
   info->geometry.max_height = 512;
   info->geometry.aspect_ratio = 4.0 / 3.0;
   //   if (!Settings.PAL)
   //      info->timing.fps = 21477272.0 / 357366.0;
   //   else
   //      info->timing.fps = 21281370.0 / 425568.0;
   //   info->timing.sample_rate = 32040.5;


   info->timing.fps = 60.0;
   info->timing.sample_rate = 32040.0;
}

void retro_reset(void)
{
   CPU.Flags = 0;
   S9xReset();
}


size_t retro_serialize_size(void)
{
   return sizeof(CPU) + sizeof(ICPU) + sizeof(PPU) + sizeof(DMA) +
          0x10000 + 0x20000 + 0x20000 + 0x8000 + sizeof(APU) +
          sizeof(IAPU) + 0x10000 + sizeof(SA1) +
          sizeof(s7r) + sizeof(rtc_f9);
}

bool retro_serialize(void* data, size_t size)
{
   int i;

   S9xUpdateRTC();
   S9xSRTCPreSaveState();

   for (i = 0; i < 8; i++)
   {
      SoundData.channels[i].previous16[0] = (int16)
                                            SoundData.channels[i].previous[0];
      SoundData.channels[i].previous16[1] = (int16)
                                            SoundData.channels[i].previous[1];
   }

   uint8_t* buffer = data;
   memcpy(buffer, &CPU, sizeof(CPU));
   buffer += sizeof(CPU);
   memcpy(buffer, &ICPU, sizeof(ICPU));
   buffer += sizeof(ICPU);
   memcpy(buffer, &PPU, sizeof(PPU));
   buffer += sizeof(PPU);
   memcpy(buffer, &DMA, sizeof(DMA));
   buffer += sizeof(DMA);
   memcpy(buffer, Memory.VRAM, 0x10000);
   buffer += 0x10000;
   memcpy(buffer, Memory.RAM, 0x20000);
   buffer += 0x20000;
   memcpy(buffer, Memory.SRAM, 0x20000);
   buffer += 0x20000;
   memcpy(buffer, Memory.FillRAM, 0x8000);
   buffer += 0x8000;
   memcpy(buffer, &APU, sizeof(APU));
   buffer += sizeof(APU);
   memcpy(buffer, &IAPU, sizeof(IAPU));
   buffer += sizeof(IAPU);
   memcpy(buffer, IAPU.RAM, 0x10000);
   buffer += 0x10000;

   SA1.Registers.PC = SA1.PC - SA1.PCBase;
   S9xSA1PackStatus();

   memcpy(buffer, &SA1, sizeof(SA1));
   buffer += sizeof(SA1);
   memcpy(buffer, &s7r, sizeof(s7r));
   buffer += sizeof(s7r);
   memcpy(buffer, &rtc_f9, sizeof(rtc_f9));
   buffer += sizeof(rtc_f9);

   return true;
}
bool retro_unserialize(const void* data, size_t size)
{   
   const uint8_t* buffer = data;

   if (size != retro_serialize_size())
      return false;

   S9xReset();

   uint8* IAPU_RAM_current = IAPU.RAM;

   memcpy(&CPU, buffer, sizeof(CPU));
   buffer += sizeof(CPU);
   memcpy(&ICPU, buffer, sizeof(ICPU));
   buffer += sizeof(ICPU);
   memcpy(&PPU, buffer, sizeof(PPU));
   buffer += sizeof(PPU);
   memcpy(&DMA, buffer, sizeof(DMA));
   buffer += sizeof(DMA);
   memcpy(Memory.VRAM, buffer, 0x10000);
   buffer += 0x10000;
   memcpy(Memory.RAM, buffer, 0x20000);
   buffer += 0x20000;
   memcpy(Memory.SRAM, buffer, 0x20000);
   buffer += 0x20000;
   memcpy(Memory.FillRAM, buffer, 0x8000);
   buffer += 0x8000;
   memcpy(&APU, buffer, sizeof(APU));
   buffer += sizeof(APU);
   memcpy(&IAPU, buffer, sizeof(IAPU));
   buffer += sizeof(IAPU);
   IAPU.PC = IAPU_RAM_current + (IAPU.PC - IAPU.RAM);
   IAPU.DirectPage = IAPU_RAM_current + (IAPU.DirectPage - IAPU.RAM);
   IAPU.RAM = IAPU_RAM_current;
   memcpy(IAPU.RAM, buffer, 0x10000);
   buffer += 0x10000;

   memcpy(&SA1, buffer, sizeof(SA1));
   buffer += sizeof(SA1);
   memcpy(&s7r, buffer, sizeof(s7r));
   buffer += sizeof(s7r);
   memcpy(&rtc_f9, buffer, sizeof(rtc_f9));
   buffer += sizeof(rtc_f9);

   S9xFixSA1AfterSnapshotLoad();
   FixROMSpeed();
   IPPU.ColorsChanged = TRUE;
   IPPU.OBJChanged = TRUE;
   CPU.InDMA = FALSE;
   S9xFixColourBrightness();

   S9xAPUUnpackStatus();
   S9xSA1UnpackStatus();
   S9xFixSoundAfterSnapshotLoad();
   ICPU.ShiftedPB = ICPU.Registers.PB << 16;
   ICPU.ShiftedDB = ICPU.Registers.DB << 16;
   S9xSetPCBase(ICPU.ShiftedPB + ICPU.Registers.PC);
   S9xUnpackStatus();
   S9xFixCycles();
   S9xReschedule();

   return true;
}

void retro_cheat_reset(void)
{

}
void retro_cheat_set(unsigned index, bool enabled, const char* code)
{

}

bool retro_load_game(const struct retro_game_info* game)

{
   CPU.Flags = 0;

   if (!LoadROM(game->path))
      return false;

   Settings.FrameTime = (Settings.PAL ? Settings.FrameTimePAL :
                         Settings.FrameTimeNTSC);

   return LoadSRAM(S9xGetFilename(".srm"));
}

bool retro_load_game_special(unsigned game_type,
                             const struct retro_game_info* info, size_t num_info)
{
   return false;
}
void retro_unload_game(void)
{

}

void* retro_get_memory_data(unsigned id)
{
   return NULL;
}

size_t retro_get_memory_size(unsigned id)
{
   return 0;
}