view hgeditor @ 2080:1cbb14c048cb

Reduce index memory usage by storing the bare string instead of tuples

Storing the tuple returned by struct.unpack significantly increases
the memory required to store the entire index in ram.  This patch
uses struct.unpack on demand instead.

#!/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" 1 2 3 6 15 # HUP INT QUIT ABRT TERM

HGTMP="${TMPDIR-/tmp}/hgeditor.$RANDOM.$RANDOM.$RANDOM.$$"
(umask 077 && mkdir "$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"

CHECKSUM=`md5sum "$HGTMP/msg"`
if [ -s "$HGTMP/diff" ]; then
    $EDITOR "$HGTMP/msg" "$HGTMP/diff" || exit $?
else
    $EDITOR "$HGTMP/msg" || exit $?
fi
echo "$CHECKSUM" | md5sum -c >/dev/null 2>&1 && exit 13

mv "$HGTMP/msg" "$1"

exit $?