giteditor.sh

#!/bin/sh
#
# This is a modification of the excellent script HGEDITOR.SH that is
# distributed with the Mercurial version control system. I've simply
# modified it to work with Git.
#

[ -z "${GIT}" ] || GIT=`which git`
[ -z "${GIT_EDITOR_EDITOR}" ] || EDITOR="${GIT_EDITOR_EDITOR}"

case "${EDITOR}" in
    "")
        EDITOR="vi"
        ;;
    emacs)
        EDITOR="${EDITOR} -nw"
        ;;
    gvim|vim)
        EDITOR="${EDITOR} -f -o"
        ;;
esac


GITTMP=""

cleanup_exit() {
    rm -rf "${GITTMP}"
}

# Remove temporary files even if we get interrupted
trap "cleanup_exit" 0 # normal exit
trap "exit 255" HUP INT QUIT ABRT TERM

GITTMP=$(mktemp -d ${TMPDIR-/tmp}/giteditor.XXXXXX)

[ ${GITTMP} != x -a -d ${GITTMP} ] || {
  echo "Could not create temporary directory! Exiting." 1>&2
  exit 1
}

(
    "${GIT}" diffall >> "${GITTMP}/diff"
)

cat "$1" > "${GITTMP}/msg"

MD5=$(which md5sum 2>/dev/null) || MD5=$(which md5 2>/dev/null)

[ -x "${MD5}" ] && CHECKSUM=`${MD5} "${GITTMP}/msg"`
if [ -s "${GITTMP}/diff" ]; then
    ${EDITOR} "+e ${GITTMP}/diff" '+set buftype=help filetype=diff' "+vsplit ${GITTMP}/msg" '+set filetype=gitcommit tw=78' || exit $?
else
    ${EDITOR} -c "r ${TEMPLATE}" "${GITTMP}/msg" || exit $?
fi

[ -x "${MD5}" ] && (echo "${CHECKSUM}" | ${MD5} -c >/dev/null 2>&1 && exit 13)

mv "${GITTMP}/msg" "$1"

exit $?