Apply jpegoptim on makepkg (similar to optipng)

usr-share-makepkg-tidy-jpegoptim.sh

#!/usr/bin/bash
#
#   jpegoptim.sh - Compress JPG files using jpegoptim
#
#   Copyright (c) 2015-2016 Pacman Development Team <[email protected]>
#
#   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 2 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/>.
#

[[ -n "$LIBMAKEPKG_TIDY_JPEGOPTIM_SH" ]] && return
LIBMAKEPKG_TIDY_JPEGOPTIM_SH=1

LIBRARY=${LIBRARY:-'/usr/share/makepkg'}

source "$LIBRARY/util/message.sh"
source "$LIBRARY/util/option.sh"


packaging_options+=('jpegoptim')
tidy_modify+=('tidy_jpegoptim')

tidy_jpegoptim() {
	if check_option "jpegoptim" "y"; then
		msg2 "$(gettext "Optimizing JPEG images...")"
		local jpeg
		find . -type f -iname "*.jpeg" -o -iname "*.jpg" 2>/dev/null | while read -r jpeg ; do
			if [[ $(file --brief --mime-type "$jpeg") = 'image/jpeg' ]]; then
				jpegoptim "${JPEGOPTIMFLAGS[@]}" "$jpeg" &>/dev/null ||
					warning "$(gettext "Could not optimize JPEG image : %s")" "${jpeg/$pkgdir\//}"
			fi
		done
	fi
}