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#include <u.h>
#include <libc.h>
#include <draw.h>
#include <thread.h>
#include <mouse.h>
#include <keyboard.h>
#include "dat.h"
#include "fns.h"
extern uchar ppuram[16384];
int nprg, nchr, map;
uchar *prg, *chr;
int scale;
Rectangle picr;
Image *tmp, *bg;
int clock, ppuclock, syncclock, syncfreq, checkclock, sleeps;
Mousectl *mc;
int keys;
extern void (*mapper[])(int, u8int);
int mirr;
void
loadrom(char *file)
{
int fd;
int nes20;
static uchar header[16];
static u32int flags;
fd = open(file, OREAD);
if(fd < 0)
sysfatal("open: %r");
if(readn(fd, header, sizeof(header)) < sizeof(header))
sysfatal("read: %r");
if(memcmp(header, "NES\x1a", 4) != 0)
sysfatal("not a ROM");
if(header[15] != 0)
memset(header + 7, 0, 9);
flags = header[6] | header[7] << 8;
nes20 = (flags & FLNES20M) == FLNES20V;
if(flags & (FLVS | FLPC10))
sysfatal("ROM not supported");
nprg = header[HPRG];
if(nes20)
nprg |= (header[HROMH] & 0xf) << 8;
if(nprg == 0)
sysfatal("invalid ROM");
nchr = header[HCHR];
if(nes20)
nchr |= (header[HROMH] & 0xf0) << 4;
map = (flags >> FLMAPPERL) & 0x0f | (((flags >> FLMAPPERH) & 0x0f) << 4);
if(nes20)
map |= (header[8] & 0x0f) << 8;
if(map >= 256 || mapper[map] == nil)
sysfatal("unimplemented mapper %d", map);
memset(mem, 0, sizeof(mem));
if((flags & FLTRAINER) != 0 && readn(fd, mem + 0x7000, 512) < 512)
sysfatal("read: %r");
prg = malloc(nprg * PRGSZ);
if(prg == nil)
sysfatal("malloc: %r");
if(readn(fd, prg, nprg * PRGSZ) < nprg * PRGSZ)
sysfatal("read: %r");
if(nchr != 0){
chr = malloc(nchr * CHRSZ);
if(chr == nil)
sysfatal("malloc: %r");
if(readn(fd, chr, nchr * CHRSZ) < nchr * CHRSZ)
sysfatal("read: %r");
}else{
nchr = 16;
chr = malloc(16 * CHRSZ);
if(chr == nil)
sysfatal("malloc: %r");
}
if((flags & FLFOUR) != 0)
mirr = MFOUR;
else if((flags & FLMIRROR) != 0)
mirr = MVERT;
else
mirr = MHORZ;
mapper[map](-1, 0);
}
void
keyproc(void *)
{
int fd;
char buf[256], *s;
Rune r;
fd = open("/dev/kbd", OREAD);
if(fd < 0)
sysfatal("open: %r");
for(;;){
if(read(fd, buf, 256) <= 0)
sysfatal("read /dev/kbd: %r");
if(buf[0] == 'c'){
if(utfrune(buf, Kdel))
threadexitsall(nil);
}
if(buf[0] != 'k' && buf[0] != 'K')
continue;
s = buf + 1;
keys = 0;
while(*s != 0){
s += chartorune(&r, s);
switch(r){
case Kdel: threadexitsall(nil);
case 'x': keys |= 1<<0; break;
case 'z': keys |= 1<<1; break;
case Kshift: keys |= 1<<2; break;
case 10: keys |= 1<<3; break;
case Kup: keys |= 1<<4; break;
case Kdown: keys |= 1<<5; break;
case Kleft: keys |= 1<<6; break;
case Kright: keys |= 1<<7; break;
}
}
}
}
void
threadmain(int argc, char **argv)
{
int t;
Point p;
uvlong old, new, diff;
scale = 1;
ARGBEGIN {
case '2':
scale = 2;
break;
case '3':
scale = 3;
break;
} ARGEND;
if(argc < 1)
sysfatal("missing argument");
loadrom(argv[0]);
if(initdraw(nil, nil, nil) < 0)
sysfatal("initdraw: %r");
mc = initmouse(nil, screen);
if(mc == nil)
sysfatal("initmouse: %r");
proccreate(keyproc, nil, 8192);
originwindow(screen, Pt(0, 0), screen->r.min);
p = divpt(addpt(screen->r.min, screen->r.max), 2);
picr = (Rectangle){subpt(p, Pt(scale * 128, scale * 120)), addpt(p, Pt(scale * 128, scale * 120))};
if(screen->chan != XRGB32)
tmp = allocimage(display, Rect(0, 0, scale * 256, scale * 240), XRGB32, 0, 0);
bg = allocimage(display, Rect(0, 0, 1, 1), screen->chan, 1, 0xCCCCCCFF);
draw(screen, screen->r, bg, nil, ZP);
pc = memread(0xFFFC) | memread(0xFFFD) << 8;
rP = FLAGI;
syncfreq = FREQ / 30;
old = nsec();
for(;;){
t = step() * 12;
clock += t;
ppuclock += t;
syncclock += t;
checkclock += t;
while(ppuclock >= 4){
ppustep();
ppuclock -= 4;
}
if(syncclock >= syncfreq){
sleep(10);
sleeps++;
syncclock = 0;
}
if(checkclock >= FREQ){
new = nsec();
diff = new - old - sleeps * 10 * MILLION;
diff = BILLION - diff;
if(diff <= 0)
syncfreq = FREQ;
else
syncfreq = ((vlong)FREQ) * 10 * MILLION / diff;
if(syncfreq < FREQ / 100)
syncfreq = FREQ / 100;
old = new;
checkclock = 0;
sleeps = 0;
}
}
}
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