ref: b0d33c09ff8fdb48e12843046033d1df68c9c54f
dir: /sys/src/games/snes/snes.c/
#include <u.h> #include <libc.h> #include <thread.h> #include <draw.h> #include <keyboard.h> #include <mouse.h> #include "../eui.h" #include "dat.h" #include "fns.h" uchar *prg, *sram; int nprg, nsram, hirom, battery; int ppuclock, spcclock, dspclock, stimerclock, saveclock, msgclock, cpupause; Channel *msgc; int savefd, mouse; void flushram(void) { if(savefd >= 0) pwrite(savefd, sram, nsram, 0); saveclock = 0; } void loadrom(char *file) { int fd; vlong size; fd = open(file, OREAD); if(fd < 0) sysfatal("open: %r"); size = seek(fd, 0, 2); if(size < 0) sysfatal("seek: %r"); if(size == 0) sysfatal("empty file"); if((size & 1023) == 512){ size -= 512; seek(fd, 512, 0); }else if((size & 1023) == 0) seek(fd, 0, 0); else sysfatal("invalid rom size"); if(size >= 16*1048576) sysfatal("rom too big"); nprg = (size + 32767) / 32768; prg = malloc(nprg * 32768); if(prg == nil) sysfatal("malloc: %r"); if(readn(fd, prg, size) < size) sysfatal("read: %r"); close(fd); if(hirom < 0){ hirom = 0; if((memread(0xffd5) & ~0x10) != 0x20) if((memread(0x1ffd5) & ~0x10) == 0x21) hirom = 1; else sysfatal("invalid rom (ffd5 = %.2x, 1ffd5 = %.2x)", memread(0xffd5), memread(0x1ffd5)); } if(hirom) nprg >>= 1; switch(memread(0xffd6)){ case 0: break; case 2: battery++; case 1: nsram = memread(0xffd8); if(nsram == 0) break; if(nsram >= 0x0c) sysfatal("invalid rom (too much ram specified)"); nsram = 1<<(nsram + 10); sram = malloc(nsram); if(sram == nil) sysfatal("malloc: %r"); break; default: print("unknown rom type %d\n", memread(0xffd5)); } } void loadbat(char *file) { static char buf[512]; char *s; if(battery && nsram != 0){ buf[sizeof buf - 1] = 0; strncpy(buf, file, sizeof buf - 5); s = buf + strlen(buf) - 4; if(s < buf || strcmp(s, ".smc") != 0) s += 4; strcpy(s, ".sav"); savefd = create(buf, ORDWR | OEXCL, 0666); if(savefd < 0) savefd = open(buf, ORDWR); if(savefd < 0) message("open: %r"); else readn(savefd, sram, nsram); atexit(flushram); } } void usage(void) { fprint(2, "usage: %s [-23ahmsT] [-x scale] rom\n", argv0); exits("usage"); } void threadmain(int argc, char **argv) { int t; extern u16int pc; hirom = -1; ARGBEGIN { case 'a': audioinit(); break; case 's': battery++; break; case 'm': mouse++; keys = 1<<16; break; case 'h': hirom++; break; case 'x': fixscale = strtol(EARGF(usage()), nil, 0); break; default: usage(); } ARGEND; if(argc < 1) usage(); loadrom(argv[0]); initemu(256, 239, 2, RGB15, !mouse, nil); regkey("b", 'z', 1<<31); regkey("a", 'x', 1<<23); regkey("y", 'a', 1<<30); regkey("x", 's', 1<<22); regkey("l1", 'q', 1<<21); regkey("r1", 'w', 1<<20); regkey("control", Kshift, 1<<29); regkey("start", '\n', 1<<28); regkey("up", Kup, 1<<27); regkey("down", Kdown, 1<<26); regkey("left", Kleft, 1<<25); regkey("right", Kright, 1<<24); msgc = chancreate(sizeof(char*), 1); loadbat(argv[0]); cpureset(); memreset(); spcreset(); dspreset(); for(;;){ if(savereq){ savestate("snes.save"); savereq = 0; } if(loadreq){ loadstate("snes.save"); loadreq = 0; } if(paused){ qlock(&pauselock); qunlock(&pauselock); } if(cpupause){ t = 40; cpupause = 0; }else t = cpustep(); spcclock -= t; stimerclock += t; ppuclock += t; dspclock += t; while(ppuclock >= 4){ ppustep(); ppuclock -= 4; } while(spcclock < 0) spcclock += spcstep() * SPCDIV; while(stimerclock >= SPCDIV*16){ spctimerstep(); stimerclock -= SPCDIV*16; } while(dspclock >= SPCDIV){ dspstep(); dspclock -= SPCDIV; } if(saveclock > 0){ saveclock -= t; if(saveclock <= 0) flushram(); } if(msgclock > 0){ msgclock -= t; if(msgclock <= 0){ sendp(msgc, nil); /* clear message */ msgclock = 0; } } } } void flush(void) { char *s; Mouse m; Point p; extern Rectangle picr; extern Mousectl *mc; flushmouse(!mouse); while(mouse && nbrecv(mc->c, &m) > 0){ if(ptinrect(m.xy, picr)){ p = subpt(m.xy, picr.min); p.x /= scale; p.y /= scale; keys = keys & 0xff3f0000 | p.x | p.y << 8; if((m.buttons & 1) != 0) keys |= 1<<22; if((m.buttons & 4) != 0) keys |= 1<<23; if((m.buttons & 2) != 0) lastkeys = keys; } } flushscreen(); while(nbrecv(msgc, &s) > 0){ if(s != nil){ string(screen, addpt(screen->r.min, Pt(10, 10)), display->black, ZP, display->defaultfont, s); free(s); flushimage(display, 1); } } flushaudio(audioout); } void message(char *fmt, ...) { va_list va; va_start(va, fmt); sendp(msgc, vsmprint(fmt, va)); msgclock = FREQ; va_end(va); }