[src/trunk]: src/sbin/fsirand Don't use 1st alternate superblock at offset 64...

[dsl <dsl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/adf11eb54bec
branches:  trunk
changeset: 559675:adf11eb54bec
user:      dsl <dsl%NetBSD.org@localhost>
date:      Sun Mar 21 20:12:16 2004 +0000

description:
Don't use 1st alternate superblock at offset 64k for ffsv1.
Fixes part of PR kern/24809

diffstat:

 sbin/fsirand/fsirand.c |  28 +++++++++++++---------------
 1 files changed, 13 insertions(+), 15 deletions(-)

diffs (66 lines):

diff -r d86d0f43eab0 -r adf11eb54bec sbin/fsirand/fsirand.c
--- a/sbin/fsirand/fsirand.c    Sun Mar 21 20:01:41 2004 +0000
+++ b/sbin/fsirand/fsirand.c    Sun Mar 21 20:12:16 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fsirand.c,v 1.23 2004/01/05 23:23:33 jmmv Exp $        */
+/*     $NetBSD: fsirand.c,v 1.24 2004/03/21 20:12:16 dsl Exp $ */
 
 /*-
  * Copyright (c) 1997 The NetBSD Foundation, Inc.
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: fsirand.c,v 1.23 2004/01/05 23:23:33 jmmv Exp $");
+__RCSID("$NetBSD: fsirand.c,v 1.24 2004/03/21 20:12:16 dsl Exp $");
 #endif /* lint */
 
 #include <sys/param.h>
@@ -96,12 +96,10 @@
 {
        int i;
 
-       for (i = 0; sblock_try[i] != -1; i++) {
-
-               if (lseek(fd, sblock_try[i] , SEEK_SET) == (off_t) -1)
-                       continue;
-
-               if (read(fd, fs, SBLOCKSIZE) != SBLOCKSIZE)
+       for (i = 0; ; i++) {
+               if (sblock_try[i] == -1)
+                       errx(1, "%s: can't find superblock", name);
+               if (pread(fd, fs, SBLOCKSIZE, sblock_try[i]) != SBLOCKSIZE)
                        continue;
 
                switch(fs->fs_magic) {
@@ -109,23 +107,23 @@
                        is_ufs2 = 1;
                        /* FALLTHROUGH */
                case FS_UFS1_MAGIC:
-                       goto found;
+                       break;
                case FS_UFS2_MAGIC_SWAPPED:
                        is_ufs2 = 1;
                        /* FALLTHROUGH */
                case FS_UFS1_MAGIC_SWAPPED:
                        needswap = 1;
-                       goto found;
+                       ffs_sb_swap(fs, fs);
+                       break;
                default:
                        continue;
                }
+
+               if (!is_ufs2 && sblock_try[i] == SBLOCK_UFS2)
+                       continue;
+               break;
        }
 
-       errx(1, "%s: can't find superblock", name);
-found:
-       if (needswap)
-               ffs_sb_swap(fs, fs);
-
        if (fs->fs_ncg < 1)
                errx(1, "%s: bad ncg in superblock", name);