source: npl/signpkg @ 13a1b25

#!/bin/bash

PKGDIR=/tmp/$$.signpkg

if ! [ "$GPG_AGENT_INFO" ];then
        echo "Please run gpg agent with:"
        echo "gpg-agent --daemon bash"
        exit 1
fi

trap "rm -rf $PKGDIR" 0

while true; do 
        PKG=$1
        shift
        [ "$PKG" ] || exit 0
        
        if ! echo "$PKG" | grep '^/' >/dev/null; then
                BASENAME="`pwd`/$PKG"
        else
                BASENAME="$PKG"
        fi

        if [ -f "$BASENAME.asc" ]; then
                echo "$PKG is already signed, skipping..."
                continue
        fi
        
        rm -rf "$PKGDIR" 2>/dev/null
        mkdir "$PKGDIR" || exit 1

        echo "Checksumming $PKG..."
        md5sum -b $PKG  > $BASENAME.tmp
        
        echo "Extracting $PKG..."
        tar --exclude 'dev/*' --no-same-permissions --no-same-owner --directory $PKGDIR -xzf $PKG || exit 1
        chmod -R 755 $PKGDIR || exit 1
        
        echo "Checksumming files..."
        pushd $PKGDIR >/dev/null || exit 1
        find -type f -exec md5sum -b "{}" \; >> $BASENAME.tmp || exit 1
        popd >/dev/null

        echo "Signing $BASENAME.tmp..."
        gpg --clearsign $BASENAME.tmp || exit 1
        rm $BASENAME.tmp || exit 1
        mv $BASENAME.tmp.asc $BASENAME.asc || exit 1
done