view hgeditor @ 18939:aab0c14c20d0

subrepo: implement "storeclean" method for mercurial subrepos

The mercurial subrepo "storeclean" method works by calculating a "store hash" of
the repository state and comparing it to a cached store hash. The store hash is
always cached when the repository is cloned from or pushed to a remote
repository, but also on pull as long as the repository already had a clean
store. If the hashes match the store is "clean" versus the selected repository.

Note that this method is currenty unused, but it will be used by a later patch.

The store hash is calculated by hashing several key repository files, such as
the bookmarks file the phaseroots file and the changelog. Note that the hash
comparison is done file by file so that we can exit early if a pair of hashes
do not match. Also the hashes are calculated starting with the file that is
most likely to be smaller upto the file that is more likely to be larger.

#!/bin/sh
#
# This is an example of using HGEDITOR to create of diff to review the
# changes while commiting.

# If you want to pass your favourite editor some other parameters
# only for Mercurial, modify this:
case "${EDITOR}" in
    "")
        EDITOR="vi"
        ;;
    emacs)
        EDITOR="$EDITOR -nw"
        ;;
    gvim|vim)
        EDITOR="$EDITOR -f -o"
        ;;
esac


HGTMP=""
cleanup_exit() {
    rm -rf "$HGTMP"
}

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

HGTMP=$(mktemp -d ${TMPDIR-/tmp}/hgeditor.XXXXXX)
[ x$HGTMP != x -a -d $HGTMP ] || {
  echo "Could not create temporary directory! Exiting." 1>&2
  exit 1
}

(
    grep '^HG: changed' "$1" | cut -b 13- | while read changed; do
        "$HG" diff "$changed" >> "$HGTMP/diff"
    done
)

cat "$1" > "$HGTMP/msg"

MD5=$(which md5sum 2>/dev/null) || \
    MD5=$(which md5 2>/dev/null)
[ -x "${MD5}" ] && CHECKSUM=`${MD5} "$HGTMP/msg"`
if [ -s "$HGTMP/diff" ]; then
    $EDITOR "$HGTMP/msg" "$HGTMP/diff" || exit $?
else
    $EDITOR "$HGTMP/msg" || exit $?
fi
[ -x "${MD5}" ] && (echo "$CHECKSUM" | ${MD5} -c >/dev/null 2>&1 && exit 13)

mv "$HGTMP/msg" "$1"

exit $?