liba52/compare.c

   1 // File written by Michael Niedermayer and it is under GPL.
   2 // Simple file compare program, it finds the number of rounding errors
   3 // and dies if there is too large an error ( ABS(a-b)>1 ).
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7
   8 // FIXME: No checks but it is just for debugging so who cares ;)
   9
  10 int main(int argc, char **argv)
  11 {
  12         FILE *f0, *f1;
  13         int dif=0;
  14
  15         if(argc!=3)
  16         {
  17                 printf("compare <file1> <file2>\n");
  18                 exit(2);
  19         }
  20
  21         f0= fopen(argv[1], "rb");
  22         f1= fopen(argv[2], "rb");
  23
  24         for(;;)
  25         {
  26                 short c0;
  27                 short c1;
  28                 int d;
  29
  30                 int e0= fread(&c0, 2, 1, f0);
  31                 int e1= fread(&c1, 2, 1, f1);
  32
  33                 d=c0-c1;
  34                 if(e0==0 && e1==0) break;
  35                 if(e0==0 || e1==0)
  36                 {
  37                         printf("FATAL error, files have different size!\n");
  38                         exit(1);
  39                 }
  40
  41                 if(d<0) d=-d; // ABS
  42                 if(d>1)
  43                 {
  44                         printf("FATAL error, too large a difference found (%d)!\n", d);
  45                         exit(1);
  46                 }
  47
  48                 if(d) dif++;
  49         }
  50
  51         fclose(f0);
  52         fclose(f1);
  53
  54         printf("%d (+/-1)differences found\n", dif);
  55         exit(0);
  56 }
  57