cksum.c: further match gnu cksum algo, crc with file length.

diff --git a/Applications/util/cksum.c b/Applications/util/cksum.c
index c3b1813..20319e4 100644 (file)
--- a/Applications/util/cksum.c
+++ b/Applications/util/cksum.c
@@ -84,15 +84,8 @@ static unsigned long strncrc(unsigned char *b, int n, unsigned long s)
 
   while (n-- > 0) {
        /* Compute the index to the crc table */
-       i = (s >> 24) ^ ((unsigned int) (*b++));
-
-       if (i == 0) {
-               /* Replace an intermediate zero with the next value
-                * from the sequence */
-               i = aux++;
-               if (aux >= sizeof(crctab) / sizeof(crctab[0])) aux = 0;
-       }
-
+      i = ((s >> 24) ^ *b++) & 0xff;
+       
        /* New checksum value */
        s = (s << 8) ^ crctab[i];
   }
@@ -102,7 +95,7 @@ static unsigned long strncrc(unsigned char *b, int n, unsigned long s)
 /* Compute crc and size of input file descriptor. */
 static void crc(int fd, char *name)
 {
-  off_t f_size;
+  off_t f_size,length;
   unsigned long crc;
   int nb;
 
@@ -127,6 +120,10 @@ static void crc(int fd, char *name)
        crc = strncrc(buffer, nb, crc);
   }
   close(fd);
+  length = f_size;
+  for (; length; length >>=8)
+      crc = (crc << 8) ^ crctab[((crc >> 24) ^ length) & 0xff];
+  crc = ~crc & 0xffffffff;
   printf("%lu %ld", crc, f_size);
   if (name)
        printf(" %s\n", name);