stash

#!/bin/sh -e
#
# Copyright (c) 2013 Baptiste Daroussin <bapt@FreeBSD.org>
# 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 AUTHOR 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 AUTHOR 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.

err() {
	out=$1
	shift
	echo "$@" >&2
	exit $out
}


usage() {
	echo "Usage: `basename $0` cmd

Available cmds:
ls      - display all stashed patshes
show    - view a given patch
save    - save a new patch
apply   - apply a given patch
rm      - delete a given patch from the queue
pop     - apply a patch and delete it
push    - push patches to a remote site
sync    - synchornize the stash directory is using a VCS
help    - show help" >&2
}

export LC_ALL=C

[ -x `which svn` ] || err 1 "svn is not installed on this system"
svnrp=$(svn info 2>&1 | sed -n 's/Working Copy Root Path: \(.*\)/\1/p')
[ -d "${svnrp}" ] || err 1 "should be used inside a working copy"
[ -w "${svnrp}/.svn" ] || err 1 "no write access to ${svnrp}/.svn"
patchdir=${svnrp}/.svn/patches
mkdir -p "${patchdir}" || err 1 "Impossible to create the patch directory"
[ -d ${patchdir}/.svn ] && VCS="svn"
[ -f ${patchdir}/.fslckout ] && VCS="fossil"
[ -d ${patchdir}/.git ] && VCS="git"
[ -d ${patchdir}/.hg ] && VCS="hg"


save() {
	[ $# -ge 1 ] || err 1 "Usage: `basename $0` save <name> [-uk] [files...]"
	x=`echo $1|head -c1`
	[ $x != "." ] || err 1 "The patch name must not start with '.'"
	name=$1
	patch="${patchdir}/$1.patch"
	shift
	while getopts 'uk' FLAG; do
		case ${FLAG} in
		u) update=yes ;;
		k) keep=yes ;;
		esac
	done
	shift $(( $OPTIND - 1))

	if [ -z "${update}" -a -f "${patch}" ]; then
		err 1 "A patch named ${name} already exists"
	fi
	files="$@"
	changes=$(svn st -q ${files})
	[ "${changes}" != "" ] || err 1 "No changes to be saved"
	svn diff --git ${files:-.} > "${patch}"
	if [ -z "${keep}" ]; then
		svn revert --depth=infinity ${files:-.}
		svn st ${files} | awk '/^?/ { print $2 }' | xargs rm -f
	fi
	if [ -n "${update}" -a -n "${VCS}" ]; then
		(cd ${patchdir}; ${VCS} commit)
	elif [ -n "${VCS}" ]; then
		(cd ${patchdir}; ${VCS} add ${patch##*/}; ${VCS} commit)
	fi
	echo "stashed"
	exit 0
}

list() {
	for p in ${patchdir}/*.patch; do
		[ "$p" = "${patchdir}/*.patch" ] && break
		p=${p##*/}
		echo ${p%.*}
	done
	exit 0
}

show() {
	[ $# -eq 1 ] || err 1 "Usage: `basename $0` show <name>"
	patch="${patchdir}/$1.patch"
	[ -f "${patch}" ] || err 1 "$1: no such patch"
	less "${patch}"
	exit 0
}

apply() {
	[ $# -eq 1 ] || err 1 "Usage: `basename $0` apply <name>"
	patch="${patchdir}/$1.patch"
	[ -f "${patch}" ] || err 1 "$1: no such patch"
	cd ${svnrp}
	svn patch --strip 1 "${patch}"
	exit 0
}

remove() {
	[ $# -eq 1 ] || err 1 "Usage: `basename $0` rm <name>"
	patch="${patchdir}/$1.patch"
	[ -f "${patch}" ] || err 1 "$1: no such patch"
	rm -f "${patch}"
	rm -f "${patch}"
	if [ -n "${VCS}" ]; then
		(cd ${patchdir}; ${VCS} rm ${patch##*/}; ${VCS} commit)
	fi
	exit 0
}

pop() {
	[ $# -eq 1 ] || err 1 "Usage: `basename $0` pop <name>"
	patch="${patchdir}/$1.patch"
	[ -f "${patch}" ] || err 1 "$1: no such patch"
	cd ${svnrp}
	svn patch --strip 1 "${patch}"
	remove $1
	exit 0
}

push() {
	[ $# -eq 1 ] || err 1 "Usage: `basename $0` push <name>"
	patch="${patchdir}/$1.patch"
	[ -f "${patch}" ] || err 1 "$1: no such patch"
	cd ${svnrp}
	scp "${patch}" freefall.freebsd.org:public_html
	exit 0
}

sync() {
	[ -n "${VCS}" ] || err 1 "the stash is not being versioned"
	cd ${patchdir}
	case ${VCS} in
	hg) hg pull -u && hg push ;;
	git) git pull -r && git push ;;
	fossil) fossil sync && fossil update ;;
	svn) svn update ;;
	esac
	exit 0
}

cmd=$1
shift
case $cmd in
ls) list "$@" ;;
show|save|apply|pop|push|sync) $cmd "$@" ;;
rm) remove "$@" ;;
*) usage ;;
esac