cronic

#!/bin/bash
# Based on cronic: http://habilis.net/cronic/
#
# Improvements:
# - use a secure temp directory to avoid data leaks
# - run the command in a subshell for better isolation
# - work around a bug in puppet

set -eu

tmpdir=$(mktemp -d --tmpdir cronic.XXXXXXXXXX)
out="$tmpdir"/cronic.out
err="$tmpdir"/cronic.err
trace="$tmpdir"/cronic.trace

set +e
( "$@" ) > "$out" 2> "$trace"
exit_status=$?
set -e

# Separate bash traces from error output.
trace_prefix="^${PS4:0:1}\\+${PS4:1}"
if grep --text --quiet "$trace_prefix" "$trace"; then
    grep --text --invert-match "$trace_prefix" "$trace" > "$err" || true
else
    err="$trace" # no trace detected, everything is error output
fi

# https://tickets.puppetlabs.com/browse/FACT-709
if [[ ${1##*/} == puppet && $exit_status -eq 0 ]]; then
    sed -i "\\#can't open /proc/interrupts at /usr/bin/lsdev line 15.#d" "$err"
fi

if [[ $exit_status -ne 0 || -s "$err" ]]; then
    echo "Cronic detected failure or error output for the command:"
    printf '%s\n' "$*"
    echo
    echo "EXIT STATUS: $exit_status"
    echo
    echo "ERROR OUTPUT:"
    cat "$err"
    echo
    echo "STANDARD OUTPUT:"
    cat "$out"
    if [[ $trace != $err ]]; then
        echo
        echo "TRACE-ERROR OUTPUT:"
        cat "$trace"
    fi
fi

rm -rf "$tmpdir"