#!/bin/sh
#
# Copyright (c) 2007 Silicon Graphics, Inc.  All Rights Reserved.
#
# Dump to a file the following bits of information:
#
# * version# of the output
# * mkfs info
# * statfs info
# * mount info
# * quotas - user/group/project info
# in tar format.
#
# Exit status:
# 0 success
# 1 error
# 2 mount-path is not the path for a mounted file system
#
# There will be no output to stdout
# On error, print an error msg to stderr
#

tmp=/tmp/$$
tmpdir=$tmp.xfsinfo
status=1 # by default an error status of 1
trap "rm -rf $tmp.*; exit \$status" 0 1 2 3 15
here=`pwd`
prog=`basename $0`

# Various volume info data file names to tar
version_file=version1.0
mnt_options_file=mnt_options
mkfs_options_file=mkfs_options
user_quotas_file=quotas_user
group_quotas_file=quotas_group
project_quotas_file=quotas_proj
statfs_output_file=statfs_output

_usage()
{
    echo "Usage: $prog mount-path output-file" >&2
}

#
# Look thru the mounted filesystems for $mntpt
# and if it exists there, then return the mount options,
# if it doesn't exist then return an error status
# This kills 2 birds: existence and options
#
_process_mount()
{
    # Expect mount output of form:
    #
    # device on path type fs (options)
    # /dev/root on / type xfs (rw,raw=/dev/rroot)
    #
    mntpt=$1

    mount |\
    while read device on mnt type fstype opts
    do
	if [ $on != "on" -o -z "$mnt" ]
	then
	    # some basic sanity checking
	    echo "error reading mount output" >$tmp.err
	    return
	fi
	if [ $mntpt = $mnt ]
	then
	    if [ $fstype != xfs ]
	    then
		echo "$mnt is not an XFS file system" >$tmp.err
		return
	    fi
	    echo $opts >$tmp.out
	fi
    done

    if [ -s $tmp.err ]
    then
	cat $tmp.err
	return 1
    elif [ -s $tmp.out ]
    then
	cat $tmp.out
	return 0
    else
	# Didn't find it:
	# we signify it isn't a mount point but
	# don't consider this as an error
	return 2
    fi
}

#
# Check that all programs we need are accessible
# Go thru each 1 even on failure so we see all that
# are missing.
#
_check_progs()
{
    if ! which xfs_info >/dev/null 2>&1
    then
	    echo "xfs_info not found" >$tmp.err
    fi
    if ! which xfs_io >/dev/null 2>&1
    then
	    echo "xfs_io not found" >>$tmp.err
    fi
    if ! which xfs_quota >/dev/null 2>&1
    then
	    echo "xfs_quota not found" >>$tmp.err
    fi
    if [ -s $tmp.err ]
    then
	cat $tmp.err >&2
	exit
    fi
}

if [ $# -ne 2 ]
then
    _usage
    exit
fi

_check_progs

mntpt=$1
outfile=$2

mnt_options=`_process_mount $mntpt`
sts=$?
if [ $sts -ne 0 ]
then
    # output error msg
    [ $sts -eq 1 ] && echo $mnt_options >&2
    status=$sts
    exit
fi

# create the results of each command in the tmpdir
mkdir $tmpdir
cd $tmpdir
touch $version_file
echo $mnt_options >$mnt_options_file
xfs_info $mntpt >$mkfs_options_file || exit
xfs_io -c statfs $mntpt >$statfs_output_file || exit
xfs_quota -x -c "dump -uf $user_quotas_file "   $mntpt || exit
xfs_quota -x -c "dump -gf $group_quotas_file"   $mntpt || exit
xfs_quota -x -c "dump -pf $project_quotas_file" $mntpt || exit
cd $here

tar cf $outfile -C $tmpdir \
    $version_file \
    $mnt_options_file $mkfs_options_file $statfs_output_file \
    $user_quotas_file $group_quotas_file $project_quotas_file  || exit

status=0