[PATCH] Skip identical lines in hexdump

[Christian Franke]

This skips identical lines in hexdump output, like 'od' or 'xxd -a' also do.

Christian

PS: I would suggest to change hexdump 'buf' parameter from 'char *' to 
'const void *' to avoid unnecessary casts.


2009-01-30  Christian Franke  <address@hidden>

        * lib/hexdump.c (hexdump): Print at most 3 lines if data is identical.


diff --git a/lib/hexdump.c b/lib/hexdump.c
index 9b79f45..7689edf 100644
--- a/lib/hexdump.c
+++ b/lib/hexdump.c
@@ -61,6 +61,22 @@ hexdump (unsigned long bse, char *buf, int len)
 
       grub_printf ("%s\n", line);
 
+      /* Print only first and last line of more than 3 lines are identical.  */
+      if (len >= 4 * 16
+         && ! grub_memcmp (buf, buf + 1 * 16, 16)
+         && ! grub_memcmp (buf, buf + 2 * 16, 16)
+         && ! grub_memcmp (buf, buf + 3 * 16, 16))
+       {
+         grub_printf ("*\n");
+         do
+           {
+             bse += 16;
+             buf += 16;
+             len -= 16;
+           }
+         while (len >= 3 * 16 && ! grub_memcmp (buf, buf + 2 * 16, 16));
+       }
+
       bse += 16;
       buf += 16;
       len -= cnt;