sys/src/games/gba/gba.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <thread.h>
   4 #include <draw.h>
   5 #include <keyboard.h>
   6 #include "../eui.h"
   7 #include "dat.h"
   8 #include "fns.h"
   9
  10 int cpuhalt;
  11 Image *tmp;
  12 int backup;
  13 int savefd, saveframes;
  14 int clock;
  15
  16 char *biosfile = "/sys/games/lib/gbabios.bin";
  17
  18 void
  19 writeback(void)
  20 {
  21         if(saveframes == 0)
  22                 saveframes = 15;
  23 }
  24
  25 void
  26 flushback(void)
  27 {
  28         if(savefd >= 0)
  29                 pwrite(savefd, back, nback, BACKTYPELEN);
  30         saveframes = 0;
  31 }
  32
  33 void
  34 loadbios(void)
  35 {
  36         extern uchar bios[16384];
  37
  38         int fd;
  39
  40         fd = open(biosfile, OREAD);
  41         if(fd < 0)
  42                 sysfatal("open: %r");
  43         readn(fd, bios, 16384);
  44         close(fd);
  45 }
  46
  47 int
  48 romtype(int *size)
  49 {
  50         u32int *p, n, v;
  51         union {char a[4]; u32int u;} s1 = {"EEPR"}, s2 = {"SRAM"}, s3 = {"FLAS"};
  52
  53         p = (u32int *) rom;
  54         n = nrom / 4;
  55         do{
  56                 v = *p++;
  57                 if(v == s1.u && memcmp(p - 1, "EEPROM_V", 8) == 0){
  58                         print("backup type is either eeprom4 or eeprom64 -- can't detect which one\n");
  59                         return NOBACK;
  60                 }
  61                 if(v == s2.u && memcmp(p - 1, "SRAM_V", 6) == 0){
  62                         *size = 32*KB;
  63                         return SRAM;
  64                 }
  65                 if(v == s3.u){
  66                         if(memcmp(p - 1, "FLASH_V", 7) == 0 || memcmp(p - 1, "FLASH512_V", 10) == 0){
  67                                 *size = 64*KB;
  68                                 return FLASH;
  69                         }
  70                         if(memcmp(p - 1, "FLASH1M_V", 9) == 0){
  71                                 *size = 128*KB;
  72                                 return FLASH;
  73                         }
  74                 }
  75         }while(--n);
  76         return NOBACK;
  77 }
  78
  79 int
  80 parsetype(char *s, int *size)
  81 {
  82         if(strcmp(s, "eeprom4") == 0){
  83                 *size = 512;
  84                 return EEPROM;
  85         }else if(strcmp(s, "eeprom64") == 0){
  86                 *size = 8*KB;
  87                 return EEPROM;
  88         }else if(strcmp(s, "sram256") == 0){
  89                 *size = 32*KB;
  90                 return SRAM;
  91         }else if(strcmp(s, "flash512") == 0){
  92                 *size = 64*KB;
  93                 return FLASH;
  94         }else if(strcmp(s, "flash1024") == 0){
  95                 *size = 128*KB;
  96                 return FLASH;
  97         }else
  98                 return NOBACK;
  99 }
 100
 101 void
 102 typename(char *s, int type, int size)
 103 {
 104         char *st;
 105         switch(type){
 106         case EEPROM:
 107                 st = "eeprom";
 108                 break;
 109         case FLASH:
 110                 st = "flash";
 111                 break;
 112         case SRAM:
 113                 st = "sram";
 114                 break;
 115         default:
 116                 sysfatal("typestr: unknown type %d -- shouldn't happen", type);
 117                 return;
 118         }
 119         snprint(s, BACKTYPELEN, "%s%d", st, size/128);
 120 }
 121
 122 void
 123 loadsave(char *file)
 124 {
 125         char *buf, *p;
 126         char tstr[BACKTYPELEN];
 127         int type, size;
 128
 129         buf = emalloc(strlen(file) + 4);
 130         strcpy(buf, file);
 131         p = strrchr(buf, '.');
 132         if(p == nil)
 133                 p = buf + strlen(buf);
 134         strcpy(p, ".sav");
 135         savefd = open(buf, ORDWR);
 136         if(savefd < 0){
 137                 if(backup == NOBACK){
 138                         backup = romtype(&nback);
 139                         if(backup == NOBACK){
 140                                 fprint(2, "failed to autodetect save format\n");
 141                                 free(buf);
 142                                 return;
 143                         }
 144                 }
 145                 savefd = create(buf, OWRITE, 0664);
 146                 if(savefd < 0){
 147                         fprint(2, "create: %r");
 148                         free(buf);
 149                         return;
 150                 }
 151                 memset(tstr, 0, sizeof(tstr));
 152                 typename(tstr, backup, nback);
 153                 write(savefd, tstr, sizeof(tstr));
 154                 back = emalloc(nback);
 155                 memset(back, 0, nback);
 156                 write(savefd, back, nback);
 157                 free(buf);
 158                 atexit(flushback);
 159                 return;
 160         }
 161         readn(savefd, tstr, sizeof(tstr));
 162         tstr[31] = 0;
 163         type = parsetype(tstr, &size);
 164         if(type == NOBACK || backup != NOBACK && (type != backup || nback != size))
 165                 sysfatal("%s: invalid format", buf);
 166         backup = type;
 167         nback = size;
 168         back = emalloc(nback);
 169         readn(savefd, back, nback);
 170         atexit(flushback);
 171         free(buf);
 172 }
 173
 174 void
 175 loadrom(char *file)
 176 {
 177         int fd;
 178         vlong sz;
 179
 180         fd = open(file, OREAD);
 181         if(fd < 0)
 182                 sysfatal("open: %r");
 183         sz = seek(fd, 0, 2);
 184         if(sz <= 0 || sz > 32*1024*1024)
 185                 sysfatal("invalid file size");
 186         seek(fd, 0, 0);
 187         nrom = sz;
 188         rom = emalloc(nrom);
 189         if(readn(fd, rom, sz) < sz)
 190                 sysfatal("read: %r");
 191         close(fd);
 192         loadsave(file);
 193         if(nrom == 32*KB*KB && backup == EEPROM)
 194                 nrom -= 256;
 195 }
 196
 197 void
 198 flush(void)
 199 {
 200         int x;
 201
 202         flushmouse(1);
 203         flushscreen();
 204         flushaudio(audioout);
 205
 206         if(saveframes > 0 && --saveframes == 0)
 207                 flushback();
 208
 209         if((reg[KEYCNT] & 1<<14) != 0){
 210                 x = reg[KEYCNT] & keys;
 211                 if((reg[KEYCNT] & 1<<15) != 0){
 212                         if(x == (reg[KEYCNT] & 0x3ff))
 213                                 setif(IRQKEY);
 214                 }else
 215                         if(x != 0)
 216                                 setif(IRQKEY);
 217         }
 218 }
 219
 220 void
 221 usage(void)
 222 {
 223         fprint(2, "usage: %s [-a] [-s savetype] [-b biosfile] [-x scale] rom\n", argv0);
 224         exits("usage");
 225 }
 226
 227 void
 228 threadmain(int argc, char **argv)
 229 {
 230         char *s;
 231         int t;
 232
 233         ARGBEGIN {
 234         case 'a':
 235                 audioinit();
 236                 break;
 237         case 's':
 238                 s = EARGF(usage());
 239                 backup = parsetype(s, &nback);
 240                 if(backup == NOBACK)
 241                         sysfatal("unknown save type '%s'", s);
 242                 break;
 243         case 'b':
 244                 biosfile = strdup(EARGF(usage()));
 245                 break;
 246         case 'x':
 247                 fixscale = strtol(EARGF(usage()), nil, 0);
 248                 break;
 249         default:
 250                 usage();
 251         } ARGEND;
 252         if(argc < 1)
 253                 usage();
 254
 255         loadbios();
 256         loadrom(argv[0]);
 257         initemu(240, 160, 2, CHAN4(CIgnore, 1, CBlue, 5, CGreen, 5, CRed, 5), 1, nil);
 258         regkey("b", 'z', 1<<1);
 259         regkey("a", 'x', 1<<0);
 260         regkey("l1", 'a', 1<<9);
 261         regkey("r1", 's', 1<<8);
 262         regkey("control", Kshift, 1<<2);
 263         regkey("start", '\n', 1<<3);
 264         regkey("up", Kup, 1<<6);
 265         regkey("down", Kdown, 1<<7);
 266         regkey("left", Kleft, 1<<5);
 267         regkey("right", Kright, 1<<4);
 268         eventinit();
 269         memreset();
 270         reset();
 271         for(;;){
 272                 if(savereq){
 273                         savestate("gba.save");
 274                         savereq = 0;
 275                 }
 276                 if(loadreq){
 277                         loadstate("gba.save");
 278                         loadreq = 0;
 279                 }
 280                 if(paused){
 281                         qlock(&pauselock);
 282                         qunlock(&pauselock);
 283                 }
 284                 if(dmaact)
 285                         t = dmastep();
 286                 else if(cpuhalt)
 287                         t = 8;
 288                 else
 289                         t = step();
 290                 clock += t;
 291                 if((elist->time -= t) <= 0)
 292                         popevent();
 293         }
 294 }