#define DUMPFILE "rom.dump"
#define ROMSIZE (2<<20)

#include <poll.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/mman.h>

extern const char *__progname;

static int dfd;
static unsigned char ibuf[512];
static int ibfill;
static int ibptr;
static unsigned char *rom;

static void opendump(void)
{
 void *mmrv;

 dfd = open(DUMPFILE,O_RDWR|O_CREAT,0666);
 if (dfd < 0)
  { fprintf(stderr,"%s: open %s: %s\r\n",__progname,DUMPFILE,strerror(errno));
    exit(1);
  }
 ftruncate(dfd,ROMSIZE);
 mmrv = mmap(0,ROMSIZE,PROT_READ|PROT_WRITE,MAP_FILE|MAP_SHARED,dfd,0);
 if (mmrv == MAP_FAILED)
  { fprintf(stderr,"%s: mmap %s: %s\r\n",__progname,DUMPFILE,strerror(errno));
    exit(1);
  }
 rom = mmrv;
}

static void nonblocking(int fd)
{
 fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0)|O_NONBLOCK);
}

static int get1(int tmo)
{
 struct pollfd pfd;
 int i;

 if (ibptr >= ibfill)
  { fflush(0);
    while (1)
     { ibfill = read(0,&ibuf[0],sizeof(ibuf));
       if (ibfill > 0)
	{ ibptr = 0;
	  break;
	}
       if (ibfill < 0)
	{ switch (errno)
	   { case EINTR:
		continue;
		break;
	     case EWOULDBLOCK:
		pfd.fd = 0;
		pfd.events = POLLIN | POLLRDNORM;
		i = poll(&pfd,1,tmo);
		if (i == 0) return(-1);
		continue;
		break;
	   }
	  fprintf(stderr,"%s: input read: %s\r\n",__progname,strerror(errno));
	  exit(1);
	}
       fprintf(stderr,"%s: input EOF\r\n",__progname);
       exit(1);
     }
  }
 return(ibuf[ibptr++]);
}

static void require(const char *s)
{
 int c;
 const char *sp;

 sp = s;
 while (*sp)
  { c = get1(1000);
    if (c < 0)
     { fprintf(stderr,"%s: read timeout at\r\n%.*s  <<>>  %s\r\n",
		__progname, (int)(sp-s), s, sp);
       exit(1);
     }
    if (c != (unsigned char)*sp)
     { fprintf(stderr,"%s: unexpected character %02x at\r\n%.*s  <<>>  %s\r\n",
		__progname, c, (int)(sp-s), s, sp);
       exit(1);
     }
    sp ++;
  }
}

static void drain(int tmo)
{
 do ibptr = ibfill; while (get1(tmo) >= 0);
}

static int xval(unsigned char c)
{
 switch (c)
  { case '0': return(0); break;
    case '1': return(1); break;
    case '2': return(2); break;
    case '3': return(3); break;
    case '4': return(4); break;
    case '5': return(5); break;
    case '6': return(6); break;
    case '7': return(7); break;
    case '8': return(8); break;
    case '9': return(9); break;
    case 'a': case 'A': return(10); break;
    case 'b': case 'B': return(11); break;
    case 'c': case 'C': return(12); break;
    case 'd': case 'D': return(13); break;
    case 'e': case 'E': return(14); break;
    case 'f': case 'F': return(15); break;
  }
 return(-1);
}

static void getrom(void)
{
 int a;
 int c1;
 int c2;
 int v1;
 int v2;

 for (a=0;a<ROMSIZE;a++)
  { if (! (a & 1023)) fprintf(stderr,".");
    printf("@+");
    do c1 = get1(1000); while ((c1 == '\r') || (c1 == '\n'));
    if (c1 < 0)
     { fprintf(stderr,"%s: read timeout reading byte %d\r\n",__progname,a);
       exit(1);
     }
    c2 = get1(1000);
    if (c2 < 0)
     { fprintf(stderr,"%s: read timeout reading byte %d\r\n",__progname,a);
       exit(1);
     }
    v1 = xval(c1);
    if (v1 < 0)
     { fprintf(stderr,"%s: invalid byte char #1 (%02x)\r\n",__progname,c1);
       exit(1);
     }
    v2 = xval(c2);
    if (v2 < 0)
     { fprintf(stderr,"%s: invalid byte char #2 (%02x)\r\n",__progname,c2);
       exit(1);
     }
    rom[a] = (v1 << 4) | v2;
  }
}

int main(void);
int main(void)
{
 opendump();
 ibfill = 0;
 ibptr = 0;
 nonblocking(0);
 drain(1000);
 printf("B0080000000?");
 require("addr = 80000000 value = 00");
 drain(1000);
 getrom();
 return(0);
}