dirstate-v2: Introduce a docket file
.hg/dirstate now only contains some metadata to point to a separate data file
named .hg/dirstate.{}.d with a random hexadecimal identifier. For now every
update creates a new data file and removes the old one, but later we’ll
(usually) append to an existing file.
Separating into two files allows doing the "write to a temporary file then
atomically rename into destination" dance with only a small docket file,
without always rewriting a lot of data.
Differential Revision: https://phab.mercurial-scm.org/D11088
#!/bin/sh
#
# This is an example of using HGEDITOR to create of diff to review the
# changes while committing.
# 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 $?