view hgeditor @ 24286:40528ad1b1e8

lazymanifest: don't depend on printf's 'hh' format to work

Where we convert a 20-byte binary to a 40-byte hex string in
lazymanifest_setitem(), we use sprintf("%02hhx", hash[i]). As Matt
Harbison found out, 'hh' seems to be ignored on some platforms (Visual
Studio?). If char is signed on such platforms, the value gets
sign-extended as it gets promoted into an int when passed into the
variadic sprintf(). The resulting integer value will then be printed
with leading f's (14 of them on 64-bit systems), since the '2' in the
format string indicates only minimum number of characters. This is
both incorrect and runs the risk of writing outside of allocated
memory (as Matt reported).

To fix, let's cast the value to unsigned char before passing it to
sprintf(). Also drop the poorly supported 'hh' formatting that now
becomes unnecessary.

#!/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 $?