#! /bin/sh

# Nick Urbanik <nicku@vtc.edu.hk>
# report information about the computer, reading from proc file system
# and Linux hard disk partition (if any) and storing the result in
# a directory that may be on a floppy disk.

# Designed to work with tomsrtbt or from a hard disk.

# Here is my attempt to find out whether the root device is a hard disk
# or a RAM disk.
# Now what devices are hard disks?
# could be a label (if read fstab, but not output of mount)
# could be [hs]d[a-z][1-9][0-9]*
# could be md[0-9]+
# return 0 if root partition is a hard disk
# return 1 otherwise
mounted_on_hd() {
    for line in "`mount | grep '[ \t]/[ \t]'`"
    do
        mount_point=`echo $line | awk '{print $3}'`
        if [ "$mount_point" = "/" ];
        then
            device="`echo $line | awk '{print $1}'`"
            is_hd=`echo $device |
                    awk '/^\/dev\/[hs]d[a-z][1-9][0-9]*$/ {print 0; next}
                         /^\/dev\/md[0-9]+/ {print 0; next}
                         {print 1}'`
            return $is_hd
        fi;
    done
    return 1;
}

# A utility subroutine used by other subroutines
# checks that the directory $INFODIR exists.
ensure_INFODIR_exists() {
    subroutine=$1
    if [ -z "$INFODIR" -o ! -d "$INFODIR" ]
    then
        echo $prog: $subroutine called without initialised \$INFODIR
        exit 1
    fi
}

# A utility subroutine used by other subroutines
# checks that the directory $c exists.
ensure_hd_mountpoint_exists() {
    subroutine=$1
    if [ -z "$c" -o ! -d "$c" ]
    then
        echo $prog: $subroutine called without initialised mount point \$c
        exit 1
    fi
}

# reads the output of fdisk, and dmesg,
# and copies the content of a number of files in the /proc file system.
# Assume that $INFODIR exists
report_generic_info() {
    ensure_INFODIR_exists "report_generic_info"

    fdisk -l > $INFODIR/fdisk 2>&1
    # print plenty of stuff from proc:
    for f in `ls -1 /proc|grep -v kcore|grep -v ksyms|grep -v kmsg|grep -v '[0-9].*'`
    do
        if [ ! -d /proc/$f ]; then
            echo $f:
            cat /proc/$f
            echo ' '
        fi
    done > $INFODIR/proc
    for f in /proc/sys/kernel/*
    do
        if [ ! -d $f ]; then
            echo $f:
            cat $f
            echo ' '
        fi
    done > $INFODIR/proc-kernel
    dmesg > $INFODIR/dmesg
}

# print the device names of all partitions that fdisk
# reported as having the parition type Linux
print_linux_partition_devices() {
    if [ -f $INFODIR/fdisk ]; then
        grep '83 *Linux' $INFODIR/fdisk | awk '{print $1}'
    else
        fdisk -l 2> /dev/null|grep '83 *Linux' | awk '{print $1}'
    fi
}

# print the name of the root partition device on standard output if find it.
# Assume the root partition on the hard disk is not mounted
# Assume $c exists and is a directory:
guess_root_partition() {
    ensure_hd_mountpoint_exists "guess_root_partition"
    ensure_INFODIR_exists       "guess_root_partition"

    # Oh dear, this assumes non-raid.
    # problems detecting raid, journalling file systems
    # 1. tomsrtbt won't handle raid
    # 2. How determine what raid devices exist?

    for d in `print_linux_partition_devices`
    do
        mount $d $c
        if [ -f $c/etc/fstab ]
        then
            echo $d
            umount $c
            return
        fi
        umount $c
    done
}

# takes one parameter, the partition device file.
# mount the device on $c
mount_root_partition() {
    device=$1
    if mount | grep $device > /dev/null 2>&1
    then
	# false
        return 1
    fi
    ensure_hd_mountpoint_exists "mount_root_partition"

    if mount $device $c
    then
        # true
        return 0
    else
        echo $prog: unable to mount $device on $c\; giving up
        exit 1
    fi
}

# if we have something mounted on $c, read plenty of Linux system configuration
# files from it.  We could do the same for windows, but I don't know
# enough about the registry.

copy_config_from_root_partition() {
    if mount | grep $c > /dev/null 2>&1
    then
	:
    else
        echo $prog: nothing mounted on $c\; giving up
        exit
    fi
    if $use_floppy; then
        if mount | grep $a > /dev/null 2>&1
        then
            :
        else
            echo $prog: no floppy mounted on $a\; giving up
            exit
        fi
    fi
    ensure_INFODIR_exists "copy_config_from_root_partition"
    
    for i in fstab lilo.conf conf.modules modules.conf \
             sysconfig/network issue resolv.conf hosts profile bashrc \
             inittab auto.conf
    do
        cp -p $c/etc/$i $INFODIR/$d > /dev/null 2>&1 
    done
    if [ -d $c/etc/rc.d ]
    then
        tar cf - $c/etc/rc.d 2> /dev/null | bzip2 -9 > $INFODIR/rc-d.tar.bz2
    fi
    if [ -d "$c/etc/sysconfig" ]
    then
	tar cf - $c/etc/sysconfig 2> /dev/null | bzip2 -9 > $INFODIR/sysconfig.tar.bz2
    fi
    if [ -f "$c/var/log/messages" ]
    then
	# bzip2 -9c $c/var/log/messages > $INFODIR/messages.bz2
        tail -30000 $c/var/log/messages | bzip2 -9 > $INFODIR/messages.bz2
    fi
    df > $INFODIR/df
    mount > $INFODIR/mount
}

# This subroutine is called automatically whenever the program exits,
# either because exit was called (signal zero), or an interrupt, hangup
# or terminate signal were sent to this script.

clean_up() {
    echo cleaning up...
    rmdir $a > /dev/null 2>&1
    if $use_floppy
    then
        umount $FD > /dev/null 2>&1
    fi
    if [ "$c" = "/tmp/c" ]
    then
        umount $c > /dev/null 2>&1
        rmdir $c
    fi
}

# tomsrtbt doesn't have a basename.
# given a file name like "/this/directory/name/contains/a/file",
# will print "file"
basen() {
    dir=$1;
    echo $dir | awk 'BEGIN{FS="/"}{print $NF}'
}

# find the first part of the hostname without the domain name part.
# for example, if hostname gives "nickpc.tycm.vtc.edu.hk", will print
# "nickpc"
# hostname -s doesnt work on tomsrtbt
hostname_short() {
    hostname | awk '{ sub( "\\..*$", "" ) }{ printf $0 }'
}

# tomsrtbt doesn't have tr, so can't use:
# INFODIR=$a/`date | tr ' :' '-'`
# take output from the date command (which looks like:
# Thu Feb 15 11:55:49 HKT 2001
# and replace all spaces and colons by hyphens, so it looks like this:
# Thu-Feb-15-11-55-49-HKT-2001
# Windows is not happy about the colons as a file name.
date_to_dir_name() {
    date | awk '{ gsub( "[ :]", "-" ); printf $0 }'
}

usage() {
    cat <<EOF
Usage: $prog [OPTIONS]
Read information from /proc and other sources about the computer
and write it into files in a directory.
Will search for a standard Linux root partition and read configuration
files from it if found.
Options:
    -f, --floppy	Put reports into a FAT floppy instead of /tmp/reports
    -h, --help		Show this help and exit
    -o dir, -odir	put output into dir instead of /tmp/reports
    -d, --debug		Show all commands as they are executed
EOF
    exit $1
}


prog=`basen $0`
a=/tmp/reports
c=/tmp/c
INFODIR=$a/`date_to_dir_name`-`hostname_short`

use_floppy=false
while [ $# -ne 0 ] # loop over arguments
do
    case $1 in
    --)
        shift
        break
    ;;

    -f|--floppy)
        use_floppy=true        
    ;;

    -d|--debug)
        set -x
    ;;

    -h|--help)
        usage 0 1>&2
    ;;

    -o)
        use_floppy=false
        INFODIR="$2"
        shift
    ;;

    -o*)
        use_floppy=false
        INFODIR=`echo "$1" | sed 's/-o//'`
    ;;

    *)
        echo unknown option $1
        usage 1 1>&2
    ;;
    esac
    shift
done

mkdir $c
mkdir $a > /dev/null 2>&1
if $use_floppy; then
    echo "Getting basic info about this computer..."
    echo insert a formatted floppy with some disk space, any key to continue...
    read anykey
    FD=/dev/fd0
    if mount -t vfat $FD $a
    then
        :
    else
        echo $prog: cannot mount floppy on $a\; giving up
        exit 1
    fi
fi
# cleanup on exit, hangup, interrupt, quit, termination
trap clean_up 0 1 2 3 15 
mkdir $INFODIR
report_generic_info

if mounted_on_hd
then
    c=/
    copy_config_from_root_partition
else
    device=`guess_root_partition`
    echo your root partition seems to be $device.
    mount_root_partition $device
    copy_config_from_root_partition
    umount $device
fi
$use_floppy && umount $a
rmdir $a > /dev/null 2>&1