[src/perseant-lfsv2]: src/sbin/dump_lfs Check both superblocks. If the fsb u...

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

details:   https://anonhg.NetBSD.org/src/rev/285f4d137a62
branches:  perseant-lfsv2
changeset: 511431:285f4d137a62
user:      perseant <perseant%NetBSD.org@localhost>
date:      Tue Jul 10 02:08:33 2001 +0000

description:
Check both superblocks.  If the fsb unit in the proto-superblock is > 8k,
look first for the true primary superblock at fs->lfs_sboffs[0].

diffstat:

 sbin/dump_lfs/lfs_inode.c |  57 +++++++++++++++++++++++++++++++++++++++-------
 1 files changed, 48 insertions(+), 9 deletions(-)

diffs (84 lines):

diff -r b91588eaeeb4 -r 285f4d137a62 sbin/dump_lfs/lfs_inode.c
--- a/sbin/dump_lfs/lfs_inode.c Tue Jul 10 01:47:54 2001 +0000
+++ b/sbin/dump_lfs/lfs_inode.c Tue Jul 10 02:08:33 2001 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: lfs_inode.c,v 1.2.10.1 2001/07/02 17:48:11 perseant Exp $ */
+/*      $NetBSD: lfs_inode.c,v 1.2.10.2 2001/07/10 02:08:33 perseant Exp $ */
 
 /*-
  * Copyright (c) 1980, 1991, 1993, 1994
@@ -43,7 +43,7 @@
 #if 0
 static char sccsid[] = "@(#)main.c      8.6 (Berkeley) 5/1/95";
 #else
-__RCSID("$NetBSD: lfs_inode.c,v 1.2.10.1 2001/07/02 17:48:11 perseant Exp $");
+__RCSID("$NetBSD: lfs_inode.c,v 1.2.10.2 2001/07/10 02:08:33 perseant Exp $");
 #endif
 #endif /* not lint */
 
@@ -82,19 +82,58 @@
 int
 fs_read_sblock(char *sblock_buf)
 {
+       char tbuf[LFS_SBPAD];
        int needswap = 0;
+       off_t sboff = LFS_LABELPAD;
 
        sblock = (struct lfs *)sblock_buf;
-       rawread(LFS_LABELPAD, (char *) sblock, LFS_SBPAD);
-       if (sblock->lfs_magic != LFS_MAGIC) {
+       while(1) {
+               rawread(sboff, (char *) sblock, LFS_SBPAD);
+               if (sblock->lfs_magic != LFS_MAGIC) {
+#ifdef notyet
+                       if (sblock->lfs_magic == bswap32(LFS_MAGIC)) {
+                               lfs_sb_swap(sblock, sblock, 0);
+                               needswap = 1;
+                       } else
+#endif
+                               quit("bad sblock magic number\n");
+               }
+               if (fsbtob(sblock, sblock->lfs_sboffs[0]) != sboff) {
+                       sboff = fsbtob(sblock, sblock->lfs_sboffs[0]);
+                       continue;
+               }
+               break;
+       }
+
+       /*
+        * Read the secondary and take the older of the two
+        */
+       rawread(fsbtob(sblock, sblock->lfs_sboffs[1]), tbuf, LFS_SBPAD);
 #ifdef notyet
-               if (sblock->lfs_magic == bswap32(LFS_MAGIC)) {
-                       lfs_sb_swap(sblock, sblock, 0);
-                       needswap = 1;
-               } else
+       if (needswap)
+               lfs_sb_swap(tbuf, tbuf, 0);
 #endif
-                       quit("bad sblock magic number\n");
+       if (((struct lfs *)tbuf)->lfs_magic != LFS_MAGIC) {
+               msg("Warning: secondary superblock at 0x%x bad magic\n",
+                       fsbtodb(sblock, sblock->lfs_sboffs[1]));
+       } else {
+               if (sblock->lfs_version > 1) {
+                       if (((struct lfs *)tbuf)->lfs_serial < sblock->lfs_serial) {
+                               memcpy(sblock, tbuf, LFS_SBPAD);
+                               sboff = fsbtob(sblock, sblock->lfs_sboffs[1]);
+                       }
+               } else {
+                       if (((struct lfs *)tbuf)->lfs_otstamp < sblock->lfs_otstamp) {
+                               memcpy(sblock, tbuf, LFS_SBPAD);
+                               sboff = fsbtob(sblock, sblock->lfs_sboffs[1]);
+                       }
+               }
        }
+       if (sboff != LFS_SBPAD) {
+               msg("Using superblock at alternate location 0x%lx\n",
+                   (unsigned long)(btodb(sboff)));
+       }
+
        return needswap;
 }