/* bfc.c - Don Yang (uguu.org)

   Simple BF to C compiler.

   09/06/04
                                                                           */

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

#define BUFSIZE         0x10000
#define MAX_TAPE_SIZE   0x10000


int main(int argc, char **argv)
{
   static char buffer[BUFSIZE], *p;
   FILE *infile, *outfile;
   size_t s;
   int n;

   if( argc > 1 )
   {
      if( (infile = fopen(argv[1], "rb")) == NULL )
         return printf("Can not open %s\n", argv[1]);
      if( argc > 2 )
      {
         if( (outfile = fopen(argv[2], "wb+")) == NULL )
         {
            (void)fclose(infile);
            return printf("Can not create %s\n", argv[2]);
         }
      }
      else
      {
         outfile = stdout;
      }
   }
   else
   {
      infile = stdin;
      outfile = stdout;
   }

   n = 0;
   (void)fprintf(outfile,
      "#include<stdio.h>\n"
      "#include<string.h>\n"
      "static int Tape[%d];\n"
      "int main(void)\n{\n"
      "int *x=&Tape[0];\n"
      "memset(x,0,%d*sizeof(int));\n",
      MAX_TAPE_SIZE, MAX_TAPE_SIZE);
   while( (s = fread(buffer, 1, BUFSIZE, infile)) > 0 )
   {
      for(p = buffer; s-- > 0; p++)
      {
         switch( *p )
         {
            case '[':   (void)fputs("\nwhile(*x){\n", outfile); n++; break;
            case ']':   (void)fputs("\n}\n", outfile); n--;          break;
            case '<':   (void)fputs("--x;", outfile);                break;
            case '>':   (void)fputs("++x;", outfile);                break;
            case '-':   (void)fputs("--*x;", outfile);               break;
            case '+':   (void)fputs("++*x;", outfile);               break;
            case ',':   (void)fputs("\n*x=getchar();", outfile);     break;
            case '.':   (void)fputs("putchar(*x);\n", outfile);      break;
            default: break;
         }
      }
      if( n < 0 )
         n = -2;
   }
   (void)fputs("\nreturn 0;\n}\n", outfile);
   if( n != 0 )
      (void)fputs("[] unbalanced\n", stderr);

   (void)fclose(infile);
   (void)fclose(outfile);
   return 0;
}