#!/bin/sh
# Check robust handling of SIG{INFO,USR1}

# Copyright (C) 2014 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
print_ver_ dd

env kill -l | grep '^INFO$' && SIGINFO='INFO' || SIGINFO='USR1'

# This to avoid races in the USR1 case
# as the dd process will terminate by default until
# it has its handler enabled.
trap '' $SIGINFO

mkfifo_or_skip_ fifo

for open in '' '1'; do
  # Run dd with the fullblock iflag to avoid short reads
  # which can be triggered by reception of signals
  dd iflag=fullblock if=/dev/zero of=fifo count=100 bs=5000000 2>err & pid=$!

  # Note if we sleep here we give dd a chance to exec and block on open.
  # Otherwise we're probably testing SIG_IGN in the forked shell or early dd.
  test "$open" && sleep .1

  # dd will block on open until fifo is opened for reading.
  # Timeout in case dd goes away erroneously which we check for below.
  timeout 10 sh -c 'wc -c < fifo > nwritten' &

  # Send lots of signals immediately to ensure dd not killed due
  # to race setting handler, or blocking on open of fifo.
  # Many signals also check that short reads are handled.
  until ! kill -s $SIGINFO $pid 2>/dev/null; do
    sleep .01
  done

  wait

  # Ensure all data processed and at least last status written
  grep '500000000 bytes .* copied' err || { cat err; fail=1; }
done

Exit $fail