#!/bin/sh
(if (test -t 0); then
    diff -uNr $1 $2
else
    cat
fi) | awk 'm = /^(---|\+\+\+)/ {
    if($2 != "/dev/null") {
        cmd = "shasum -a 512 \"" $2 "\" 2>/dev/null  ";
        s = cmd | getline x;
        close(cmd);
        if (s) {
            split(x, a, " ");
            o = a[1];
        } else {
            o = "false";
        }
        print $1 " " $2 " " o;
    } else {
        print $1 " " $2 " false";
    }
}
!m {
    print $0;
}'