db-walk

#!/usr/bin/perl -w
#
# Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#
#
# use db to try to traverse the entire filesystem starting at the root
#
#                                                       dxm 5/10/00

my $device;
my $rootino;
my $agcount;
my $versionnum;
my $dir_version;
my @dir_inodes;
my @bmap_blocks;
my @block_inodes;
my $mode;

sub db($)
{
    my ($args)=@_;
    my ($ret);
    
    $ret=`xfs_db -r $args $device 2> /dev/null`;
    die "ERROR executing xfs_db -r $args $device" if ($?);
    
    return $ret;
}

sub fmt($)
{
    my ($text)=@_;
    my $c=0;
    print "        ";
    foreach (split("\n",$text)) {
        s/^core\.//;
        
        if ($c+length($_) >= 70) {
            $c=0;
            print ",\n        ";
        }
        if ($c) {
            print ", ";
            $c+=2;
        }
        print "$_";
        $c+=length($_)+2;
    }
    print "\n";
}

sub inode($)
{
    my ($num)=@_;
    my ($t);
    
    @dir_inodes=();
    
    $t=db("-c \"inode $num\" -c \"print\"");
    print "    *** Inode $num\n";
    fmt($t);
    
    ($mode)= $t=~ /^core.mode = (\d+)$/m;
    
    if ($t=~ /a\.bmx/m) {
        bmap("inode $num","attr");
        foreach (@bmap_blocks) {
            attr_block($_);
        }
    }
    if (eval "$mode & 040000") {
        if ( $t=~ /sfdir/m) {
            while ($t=~ /inumber(?:\.i[48])? = (\d+)$/mg) {
                push(@dir_inodes,$1);
            }
        }
        if ( $t=~ /u\.bmx/m) {
            bmap("inode $num","dir");
            foreach (@bmap_blocks) {
                dir_block($_);
                push(@dir_inodes,@block_inodes);
            }
        }
    } else {
        bmap("inode $num","file") if ( $t=~ /u\.bmx/m);
    }
}

sub bmap($$)
{
    my ($cmd,$type)=@_;
    my ($t);
    
    @bmap_blocks=();
    
    $flag=($type eq "attr")?"-a":"";
    
    $t=db("-c \"$cmd\" -c \"bmap $flag\"");
    print "    *** bmap $type $cmd\n";
    fmt($t);
    
    if ($type eq "dir" || $type eq "attr") {
        while ($t=~ /startblock (\d+) \(.+\) count (\d+)/mg) {
            for ($b=$1;$b<$1+$2;$b++) {
                push(@bmap_blocks,$b);
            }
        }
    }
}

sub dir_block($)
{
    my ($num)=@_;
    my ($t);
    
    @block_inodes=();
    
    $type=($dir_version==2)?"dir2":"dir";
    
    $t=db("-c \"fsblock $num\" -c \"type $type\" -c \"print\"");
    print "    *** $type block $num\n";
    # need to drop . and ..
    ($self)= $t=~ /\[(\d+)\].name = \"\.\"/m;
    ($parent)= $t=~ /\[(\d+)\].name = \"\.\.\"/m;
    fmt($t);
    
    
    while ($t=~ /\[(\d+)\].inumber = (\d+)/mg) {
        next if (defined $self && $1 == $self);
        next if (defined $parent && $1 == $parent);
        push(@block_inodes, $2);
    }
}

sub attr_block($)
{
    my ($num)=@_;
    my ($t);
    
    $t=db("-c \"fsblock $num\" -c \"type attr\" -c \"print\"");
    print "    *** attr block $num\n";

    fmt($t);
}

sub sb($)
{
    my ($num)=@_;
    my ($t);
    
    $t=db("-c \"sb $num\" -c \"print\"");
    print "    *** SB $num\n";
    fmt($t);
    
    ($rootino)= $t=~ /^rootino = (\d+)$/m;
    ($agcount)= $t=~ /^agcount = (\d+)$/m;
    ($versionnum)= $t=~ /^versionnum = (0x[\da-f]+)$/m;
    $dir_version = (eval "$versionnum & 0x2000")?2:1;
}

die "Usage: $0 <XFS device>\n" unless (@ARGV == 1);

$device=shift @ARGV;
die "can't read $device\n" unless (-r $device);
die "$device is not a block device\n" unless (-b _);

chomp($HOST = `hostname -s`);

print "*** db-walk host $HOST device $device\n";

sb(0);
for ($ag=1;$ag<$agcount;$ag++) {
    sb($ag);
}

@inodes=($rootino);
while ($_ = shift @inodes) {
    inode($_);
    push(@inodes,@dir_inodes);
}