lesspipe

#!/bin/sh
##
## lessfile/lesspipe filter for less pager
## Copyright (c) 2006,2007 by Michal Nazarewicz (mina86/AT/mina86.com)
##
## Written by: Behan Webster <behanw@pobox.com>
##             Darren Stalder
##             Thomas Schoepf <schoepf@debian.org>
##             Y.Dirson
##         and Michal Nazarewicz <mina86/AT/mina86.com>
##
## 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; either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will 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, see <http://www.gnu.org/licenses/>.
##
## This is part of Tiny Applications Collection
##   -> http://tinyapps.sourceforge.net/
##

##
## See lesspipe --help for usage.
##


##
## Escape string
##
esc () {
	if [ -n "$*" ]; then
		printf %s "$*" | sed -e "s/'/'\\\\''/g"
	fi
}



##
## No arguments
##
if [ $# -eq 0 ] || [ X"$1" = X--install-lessopen ] || \
	[ X"$1" = X--install-lessfile ] || [ X"$1" = X--install-lesspipe ]; then
	FULLPATH="$(cd "$(dirname "$0")"; pwd)/${0##*/}"
	FULLPATH="$(esc "'$(esc "$FULLPATH")'")"

	LESSFILE=
	if [ X"$1" = X--install-lessopen ] || [ X"$1" = X--install-lessfile ]
	then LESSFILE=y
	elif [ X"$1" != X--install-lesspipe ] && [ X"${0##*/}" = Xlessfile ]
	then LESSFILE=y
	fi

	case "$SHELL" in
	*csh) _SET=setenv; _UNSET=unsetenv; _EQ=' ';;
	*)    _SET=export; _UNSET=unset;    _EQ='=';;
	esac

	if [ -n "$LESSFILE" ]; then
		printf "$_SET LESSOPEN$_EQ'%s';\\n$_SET LESSCLOSE$_EQ'%s';\\n" \
			"$FULLPATH --open %s" "$FULLPATH --close %s %s"
	else
		printf "$_SET LESSOPEN$_EQ'%s';\\n$_UNSET LESSCLOSE;\\n" \
			"|$FULLPATH --pipe %s"
	fi

	exit 0
fi



##
## Called as LESSCLOSE
##
if [ $# -eq 3 ] && [ X"$1" = X--close ]; then
	shift
	if [ -n "$BASH" ]; then
		if [ -O "$2" ]; then
			rm -f -- "$2"
		else
			echo "Error in deleting $2" >&2
		fi
	else
		if [ -f "$2" ]; then
			rm -f -- "$2"
		else
			echo "Error in deleting $2" >&2
		fi
	fi
	exit 0
fi



##
## Ugh?
##
if [ $# -ne 2 ] || ( [ X"$1" != X--open ] && [ X"$1" != X--pipe ] ); then
	FULLPATH="$(cd "$(dirname "$0")"; pwd)/${0##*/}"
	FULLPATH="'$(esc "$FULLPATH")'"

cat <<EOF
usage: eval "\$($FULLPATH [ <option> ])"
<option> can be:
  --install-lesspipe  installs input processor as lesspipe
  --install-lessopen  installs input processor as lessopwn
  --install-lessfile  synonym of  --install-lessopen
To enable cache when downloading files create ~/.lesscache directory.
EOF
	[ X"$1" = X--help ] || [ X"$1" = X-h ]
	exit $?
fi



##
## We were called as LESSOPEN
##
set -e
LESSFILE=; [ X"$1" = X--pipe ] || LESSFILE=y
shift


## Helper function to list contents of ISO files (CD images)
iso_list() {
	set -- "$1" "$(isoinfo -d -i "$1")"
	printf %s "$2" | grep ^Rock\.Ridge >/dev/null && set -- "$1" "$2" "$3 -R"
	printf %s "$2" | grep ^Joliet      >/dev/null && set -- "$1" "$2" "$3 -J"
	printf %s\n "$2"
	isoinfo -f $3 -i "$1"
}


## Creates temporary file and echos it's path
tmpfile () {
	set -- "${1-less-}" "$(umask)" .

	# Find temp dir
	for __TMP in "$TMPDIR" "$TMP" "$TEMP" ~/tmp /tmp; do
		if [ -n "$__TMP" ] && [ -d "$__TMP" ] && [ -w "$__TMP" ]; then
			set -- "$1" "$2" "$__TMP"
			break
		fi
	done

	# tempfile exists
	if ! which mktemp >/dev/null 2>&1 && ! which tempfile >/dev/null 2>&1
	then
		echo unable to create temporary file, \
		     mktemp or tempfile required >&2
		exit 1
	fi

	umask 077
	if which mktemp >/dev/null 2>&1; then
		mktemp "$3/$1.XXXXXXXX"
	else
		tempfile -d "$3" -p "$1"
	fi
	umask "$2"
}


## Check if application is available and executes command or prints
## error and other stuff
run () {
	if [ X"$1" = X-- ]; then
		which "$2" >/dev/null 2>&1
		return $?
	fi

	if ! which "$1" >/dev/null 2>&1; then
		printf 'No %s available.\n' "$1"
		return 1
	fi

	if [ $# -eq 1 ]; then
		return 0
	else
		"$@"
	fi
}


## Exit function
exit_function () {
	if [ X"$3" = Xdownloaded ]; then
		[ X"$5" = Xcached ] || rm -f -- "$1"
		rm -f -- "$1-err"
	fi

	if [ -n "$2" ]; then
		if [ -s "$2" ]; then
			printf %s "$2" >&3
		else
			rm -f -- "$3"
		fi
	fi
}

trap 'exit_function "$@"' 0


## Redirect output
if [ -n "$LESSFILE" ]; then
	set -- "$1" "$(tmpfile lessf-)"
	exec 3>&1 >"$2"
else
	set -- "$1" ''
fi
#exec 2>/dev/null


## User has his own fitler
[ -x ~/.lessfilter ] && ~/.lessfilter "$1" && exit 0

## URL
FILENAME="${1##*/}"
if ! [ -e "$1" ] && [ X"${1#*://}" != X"$1" ]; then
	which wget >/dev/null 2>&1 || which curl >/dev/null 2>&1 || exit 0
	FILENAME="${FILENAME%%\?*}"

	CACHE=; GET=y
	if which md5sum >/dev/null 2>&1 && [ -d ~/.lesscache ]; then
		CACHE=$(printf %s "$3" | md5sum | cut -d\  -f1)
		if [ -n "$(find "$HOME/.lesscache" -maxdepth 1 -type f \
		                -name "$CACHE" -mtime -7)" ]; then
			GET=
		fi
		set -- "$HOME/.lesscache/$CACHE" "$2" downloaded "$1" cached
	else
		set -- "$(tmpfile lessg-)" "$2" downloaded "$1"
	fi

	ERR=
	if [ -z "$GET" ]; then
		:
	elif which wget >/dev/null 2>&1; then
		wget --no-check-certificate -S -o "$1-err" -O "$1" -- "$4" || ERR=y
	else
		curl -o "$1" -s -- "$4" 2>"$1-err" || ERR=y
	fi

	if [ -n "$ERR" ]; then
		echo "Could not downlaod $4"
		echo
		cat -- "$1-err"
		rm -f -- "$1"
		exit 0
	fi
fi


## File is not readable
[ -r "$1" ] || exit 0


## Show contetn of directories
if [ -d "$1" ]; then
	/bin/ls -l -- "$1" 2>&1
	exit 0
fi


## Compressed?
FILENAME="$(printf %s "$FILENAME" | tr QWERTYUIOPASDFGHJKLZXCVBNM qwertyuiopasdfghjklzxcvbnm)"
DECOMPRESSOR=cat
case "$FILENAME" in
*.gz)          DECOMPRESSOR=gzip ; FILENAME=c${FILENAME%.*}    ;;
*.tgz)         DECOMPRESSOR=gzip ; FILENAME=c${FILENAME%.*}.tar;;
*.bz2)         DECOMPRESSOR=bzip2; FILENAME=c${FILENAME%.*}    ;;
*.tbz)         DECOMPRESSOR=bzip2; FILENAME=c${FILENAME%.*}.tar;;
*.xz)          DECOMPRESSOR=xz   ; FILENAME=c${FILENAME%.*}    ;;
*.txz)         DECOMPRESSOR=xz   ; FILENAME=c${FILENAME%.*}.tar;;
*.lzma)        DECOMPRESSOR=lzma ; FILENAME=c${FILENAME%.*}    ;;
*)                                 FILENAME=u$FILENAME
esac

if [ x"$DECOMPRESSOR" != xcat ]; then
	run $DECOMPRESSOR || exit 0
	DECOMPRESSOR="$DECOMPRESSOR -d"
fi


# Filter
case "$FILENAME" in
*.[1-9n]|*.man)
	if run nroff; then $DECOMPRESSOR <"$1" | nroff -S -mandoc -; fi
	;;
*.tar)
	if run tar  ; then $DECOMPRESSOR <"$1" | tar tvv; fi
	;;


# Other archives
u*.arj)        run unarj l "$1" ;;
u*.lha|u*.lzh) run lha v "$1" ;;
u*.cab)        run cabextract -l "$1" ;;

u*.rar|u*.r[0-9][0-9])
	if   run --   rar; then   rar v "$1"
	elif run -- unrar; then unrar v "$1"
	else echo "No rar or unrar available"
	fi
	;;

u*.jar|u*.war|u*.xpi|u*.zip)
	if   run --     unzip; then     unzip -v "$1"
	elif run -- miniunzip; then miniunzip -l "$1"
	elif run -- miniunz  ; then miniunz   -l "$1"
	else echo "No unzip, miniunzip or miniunz available"
	fi
	;;

u*.zoo)
	if   run --   zoo; then   zoo  v "$1"
	elif run -- unzoo; then unzoo -l "$1"
	else echo "No unzoo or zoo available"
	fi
	;;


## CD Images
u*.iso) run isoinfo && iso_list "$1" ;;

u*.bin|u*.raw)
	if run file && run isoinfo && file "$1" | grep -F ISO\.9660 >/dev/null;
	then iso_list "$1"; fi
	;;


## Binary software packages
u*.deb|u*.udeb)
	if run dpkg; then
		echo "$1:"
		dpkg --info "$1"
		echo
		echo '*** Contents:'
		dpkg-deb --contents "$1"
	fi
	;;

u*.rpm)
	if run rpm; then
		echo "$1:"
		rpm -q -i -p "$1"
		echo
		echo '*** Contents:'
		rpm -q -l -p "$1"
	else echo "rpm isn't available, no query on rpm package possible"; fi
	;;


## Documents, images, etc
u*.doc) run catdoc "$1" ;;
u*.dvi) run dvi2tty "$1" ;;
*.ps)   if run ps2ascii; then $DECOMPRESSOR <"$1" | run ps2ascii; fi ;;
u*.pdf)  run pdftotext "$1" - ;;

u*.gif|u*.jpeg|u*.jpg|u*.pcd|u*.png|u*.tga|u*.tiff|u*.tif)
	run identify -verbose "$1"
	;;


## Compressed file needs decompression
c*)
	$DECOMPRESSOR <"$1"
	;;

## If file was downloaded it needs to be cated
*)
	if [ X"$3" != Xdownloaded ]; then
		:
	elif [ -z "$2" ]; then
		cat -- "$1"
	elif [ X"$5" = Xcached ]; then
		cp -f -- "$1" "$2"
	else
		mv -f -- "$1" "$2"
	fi
	;;
esac