#include <stdio.h>
#include <stdlib.h>
#include <strings.h>

extern const char *__progname;

static const char *pfx;
static int printnames = 0;
static char *fn;
static char *fnp;
static int pno;
static FILE *pf;
static const char sep[] = "\n\nFrom ";
static unsigned char adv[sizeof(sep)-1][256];
static int sepx;
static const char newpref[] = "From ";

static void usage(void)
{
 fprintf(stderr,"Usage: %s [-name] file-prefix\n",__progname);
 fprintf(stderr,"(mbox file taken from stdin)\n");
 fprintf(stderr,"-name   print names of parts to stdout\n");
}

static void handleargs(int ac, char **av)
{
 while (ac > 1)
  { if (!strcmp(av[1],"-name"))
     { printnames = 1;
       ac --;
       av ++;
       continue;
     }
    break;
  }
 if (ac != 2)
  { usage();
    exit(1);
  }
 pfx = av[1];
}

static void setup(void)
{
 int pl;
 int i;
 int j;
 int k;

 pl = strlen(pfx);
 fn = malloc(pl+64);
 bcopy(pfx,fn,pl);
 fnp = fn + pl;
 pno = 1;
 pf = 0;
 sepx = 0;
 for (i=0;sep[i];i++)
  { for <"j"> (j=0;j<256;j++)
     { for (k=0;k<i;k++)
	{ if ((j == sep[i-k]) && !bcmp(&sep[0],&sep[k],i-k))
	   { adv[i][j] = k;
	     continue <"j">;
	   }
	}
       adv[i][j] = (j == sep[0]) ? i : (i+1);
     }
  }
}

static void endp(void)
{
 if (pf) fclose(pf);
 pf = 0;
 pno ++;
 sepx = 0;
}

static void openp(void)
{
 if (pf) return;
 sprintf(fnp,"%d",pno);
 pf = fopen(fn,"w");
 if (pf == 0)
  { fprintf(stderr,"%s: can't open part %s: %s\n",__progname,fn,__progname);
    exit(1);
  }
 if (printnames) printf("%s\n",fn);
}

static void pwrite(const void *buf, int len)
{
 openp();
 fwrite(buf,1,len,pf);
}

static void pput(unsigned char c)
{
 openp();
 putc(c,pf);
}

static void nextp(void)
{
 endp();
 pwrite(&newpref[0],strlen(&newpref[0]));
}

int main(int, char **);
int main(int ac, char **av)
{
 int a;

 handleargs(ac,av);
 setup();
 while (1)
  { int c;
    c = getchar();
    if (c == EOF)
     { if (sepx > 0) pwrite(&sep[0],sepx);
       break;
     }
    a = adv[sepx][c];
    if (a < 1)
     { sepx ++;
       if (! sep[sepx]) nextp();
     }
    else if (a <= sepx)
     { pwrite(&sep[0],a);
       sepx -= a - 1;
     }
    else
     { if (sepx > 0) pwrite(&sep[0],sepx);
       pput(c);
       sepx = 0;
     }
  }
 endp();
 exit(0);
}