rust-hg-core: move from `ouroboros` to `self_cell`
`ouroboros` has a fundamental soundness problem that, while not applicable
today, could become applicable given new compiler optimizations.ยน
`self_cell` is a crate that accomplishes a lot of the same things that
`ouroboros` did while remaining sound (that is, unless a new soundness issue
is discovered) by not assuming as much about the memory layout of the program.
`self_cell` has been scrutinized heavily in the past few months by very
competent people, some from the compiler team and has shown no weaknesses
for a while, with a 1.0 stable release coming out a couple months ago.
Our internal API is exactly the same, this is just an implementation detail.
To reiterate, no actual soundness issue was found with our use of `ouroboros`,
but there might be evolutions of `rustc` (or even a future separate compiler)
that could generate unsound code.
[1] https://github.com/joshua-maros/ouroboros/issues/88
#!/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 $?