pkg_pigs

#! /bin/sh
#
# Copyright (c) 2015, Peter Piwowarski
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer. 
# 2. Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
#   and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# pkg_pigs: show which packages are using up the most disk space
#
# This tool fetches and prints pkg_info(1)'s estimates size for each installed
# package, sorted in descending order by size, scaled according to a specified
# unit. By default it prints sizes in MB (SI-prefixed), to four decimal places'
# precision, and trims output to fit the terminal; all parameters are controlled
# by the environment variables below.

UNIT="${UNIT:-M}" # K/M/G/KiB/MiB/GiB
PRECISION="${PRECISION:-4}" # precision (k) for dc
LLENGTH="${LLENGTH:-45}" # total length of each output line
FLOOR="${FLOOR:-0}" # only packages larger than $FLOOR$UNIT are shown
PROGRESS="${PROGRESS:-true}" # set to false to disable progress display
NLINES="${NLINES:-24}" # set to 0 to disable trimming

endl='
'

case "$UNIT" in
	K)
		factor=1000
		;;
	M)	factor=1000000
		;;
	G)
		factor=1000000000
		;;
	KiB)
		factor=1024
		;;
	MiB)
		factor=1048576
		;;
	GiB)
		factor=1073741824
		;;
	default)
		printf '%s\n' "illegal unit $UNIT"
esac

chead() {
	if [ "$NLINES" -gt 0 ]
	then
		head -n"$NLINES"
	else
		cat
	fi
}

pkgs="$(pkg_info -q)"
records=""

for pkg in $pkgs
do
	if "$PROGRESS"
	then
		printf "%-${LLENGTH}s\\r" "$pkg"
	fi

	size="$(pkg_info -sq "$pkg")"
	ssize="$(dc -e "${PRECISION}k $size $factor / p")"
	sfloor="$((FLOOR * factor))"

	if [ "$size" -ge "$sfloor" ]
	then
		nlen="$(printf %s "$pkg" | wc -c)"
		record="$(printf "%s %$((LLENGTH - nlen))s" "$pkg" "${ssize}${UNIT}")"
		records="${records}${endl}${size}@@@${record}"
	fi
done

n=0
printf "%s" "${records%%$endl}" | sort -rn | while read -r line && ( [ $n -lt $NLINES ] || [ $NLINES -eq 0 ] )
do
	n=$((n + 1))
	printf '%d%s\n' $n "${line##*@@@}"
done