trypatch

#!/bin/sh

#
# trypatch is supposed to be drop-in replacement for patch
# The main purpose is to try applying the patch to see if it's
# applicable or fail w/o leaving you with reject files spread across
# the sources. You can run it against compressed patches
# most popular extensions are supported so you don't need to unpack
# the patch before you go.
#

TMP_FQN="/tmp/patch-$$.tmp"

my_OPTS=''

#: Del all -o -p -t -ions from command line
while :; do
	case $1 in
		-*)
			my_OPTS="$my_OPTS $1"
			shift
			;;
		--*)
			my_OPTS="$my_OPTS $1"
			shift
			;;
		--)
			shift
			break
			;;
		*)
			break
			;;
	esac
done

CAT=cat
CATFILE="$1"
case "$1" in
	*.bz2)		CAT=bzcat	;;
	*.gz)		CAT=zcat	;;
	*.xz)		CAT=xzcat	;;
	*.patch)	CAT=cat		;;
	*)		CATFILE='-'	;;
esac

"$CAT" "$CATFILE" | tee "$TMP_FQN" | patch -s --dry-run $my_OPTS 1>&- 2>&- || {
	echo 'Patch is not applicable... exiting' > /dev/stderr
	rm "$TMP_FQN"
	exit 1
}

patch -s $my_OPTS -i "$TMP_FQN" && echo Ok

rm "$TMP_FQN"