#!/bin/ksh
# @(#) chklost.ksh 2.0 95/10/22
# 90/10/29 john h. dubois iii (john@armory.com)
# 91/03/09 fixed bug which prevented chklost from being able to do 'file'
#	   on files from more than one dir (do a final read from coprocess
#	   so that coprocess pipe will be closed, so it can be opened again)
# 91/03/19 added check to determine whether filesystem name and mount dir
#	   are swapped as under UNIX, and switch them if so
# 93/02/06 Added -v option
# 95/10/22 Cleaned up, made more robust, added ability to spec fs names on
#          command line, added hrRt options.

typeset -i verbose=0

alias istrue="test 0 -ne"
alias isfalse="test 0 -eq"

name=${0##*/}
Usage="Usage: $name [-hrtv] [-R<pattern>] [filesystem ...]"
remove=false
removePat='ksh history file'
tell=false

while getopts :hvrtR: opt; do
    case $opt in
    h)
	echo \
"$name: check lost+found directories for files reconnected by fsck.
$Usage
The number of files found in the lost+found directory each filesystem is
printed, followed by a long listing of the inode data for each file and what
/bin/file thinks the file contains.  If no filesystem names are given, all
mounted filesystems (as reported by mount(ADM)) are checked.  $name can only
check mounted filesystems.  The device or mount point for a filesystem may be
given.
Options:
-h: Print this help.
-r: Remove certain files from the lost+found directories that are examined,
    based on what file(C) reports.  Removed files are those for which file(C)
    reports 'ksh history file'.
-R<pattern>: Remove any files from the lost+found directories that are examined
    whose type as reported by file(C) matches <pattern>.  <pattern> may be a
    ksh pattern, e.g. '@(ksh history file|SecureWare ttys database)'.  If a
    pattern or a string contain whitespace is given, it should be quoted to
    protect it from the shell.
-t: Used in conjunction with -r or -R.  Tell which files would be removed,
    but do not remove them.
-v: Report filesystems that have no lost files or no lost+found directory."
	exit 0
	;;
     v)
	verbose=1
	;;
    t)
	tell=true
	;;
    r)
	remove=true
	;;
    R)
	removePat=$OPTARG
	remove=true
	;;
    +?)
	print -u2 "$name: options should not be preceded by a '+'."
	exit 1
	;;
    :)
        print -r -u2 -- \
        "$name: Option '$OPTARG' requires a value.  Use -h for help."
        exit 1
        ;;
    ?)
	print -u2 "$name: $OPTARG: bad option.  Use -h for help."
	exit 1
	;;
    esac
done

# remove args that were options
let OPTIND=OPTIND-1
shift $OPTIND

# Usage: CheckFS filesys mountdir
function CheckFS {
    typeset filesys=$1 mountdir=$2 tm lfdir file fileno description

    if [[ $mountdir = /dev/* ]]; then    # if swapped, swap them back
	tm=$filesys
	filesys=$mountdir
	mountdir=$tm
    fi
    lfdir="${mountdir%/}/lost+found"    # find lost+found dir for filesystem
    # change to lost+found dir if it exists; 
    # otherwise continue with next filesystem
    if [ ! -d "$lfdir" ]; then
	istrue verbose && print -ru2 -- "$mountdir has no lost+found directory."
	return 1
    fi
    cd "$lfdir" || {
	print -ru2 "Could not cd to $mountdir"
	return 1
    }
    set -- *
    if [ "$1" = "*" ]; then
	istrue verbose && print -ru2 -- "$filesys: no files in $lfdir."
	return 0
    fi
    print -n -- "$filesys: $# files found in $lfdir"
    if $remove; then
	if $tell; then
	    print "; would remove:"
	else
	    print "; removing:"
	fi
    else
	print ""
    fi
    # start up /bin/file as a coprocess, 
    # so its output can be read along with the output of l
    /bin/file "$@" |&
    # use -d to make sure l lists only the files matched by *,
    # so its output lines will sync with /bin/file *
    l -d -- "$@" | while read file; do
	# read from /bin/file
	read -p fileno description
	fileno=${fileno%:}
	# in case something funny happens
	if [[ "$file" != *"$fileno" ]]; then
	    print -u2 "l and file out of sync."
	    return 1
	fi
	if $remove; then
	    # Must eval to match extended ksh patterns.  But, that causes
	    # simple patterns that contain spaces to be split.  Can't quote
	    # pattern because extended patterns are protected from being
	    # recognized as patterns by quotes.  So, make all expressions be
	    # extended patterns by putting @() around them.
	    if eval [[ \"\$description\" = "@($removePat)" ]]; then
		print -r -- "$file  $description"
		$tell || rm -- "$fileno"
	    fi
	else
	    print -r -- "$file  $description"
	fi
    done 
    # read from coprocess again so its pipe will be closed
    read -p
    return 0
}

if [ $# -eq 0 ]; then
    # for each filesystem listed by mount...
    /etc/mount | while read filesys on mountdir date; do
	CheckFS "$filesys" "$mountdir"
    done
else
    for fsName; do
	[[ "$fsName" != */* ]] && fsName=/dev/$fsName
	mount | egrep "(^| )$fsName " | read filesys on mountdir date &&
	CheckFS "$filesys" "$mountdir" || 
	print -u2 -- "$fsName: no such filesystem, or filesystem not mounted."
    done
fi